1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2017 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 #include "event-loop.h"
65 #include "thread-fsm.h"
66 #include "common/enum-flags.h"
68 /* Prototypes for local functions */
70 static void signals_info (char *, int);
72 static void handle_command (char *, int);
74 static void sig_print_info (enum gdb_signal
);
76 static void sig_print_header (void);
78 static void resume_cleanups (void *);
80 static int hook_stop_stub (void *);
82 static int restore_selected_frame (void *);
84 static int follow_fork (void);
86 static int follow_fork_inferior (int follow_child
, int detach_fork
);
88 static void follow_inferior_reset_breakpoints (void);
90 static void set_schedlock_func (char *args
, int from_tty
,
91 struct cmd_list_element
*c
);
93 static int currently_stepping (struct thread_info
*tp
);
95 void _initialize_infrun (void);
97 void nullify_last_target_wait_ptid (void);
99 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
101 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
103 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
105 static int maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
);
107 /* Asynchronous signal handler registered as event loop source for
108 when we have pending events ready to be passed to the core. */
109 static struct async_event_handler
*infrun_async_inferior_event_token
;
111 /* Stores whether infrun_async was previously enabled or disabled.
112 Starts off as -1, indicating "never enabled/disabled". */
113 static int infrun_is_async
= -1;
118 infrun_async (int enable
)
120 if (infrun_is_async
!= enable
)
122 infrun_is_async
= enable
;
125 fprintf_unfiltered (gdb_stdlog
,
126 "infrun: infrun_async(%d)\n",
130 mark_async_event_handler (infrun_async_inferior_event_token
);
132 clear_async_event_handler (infrun_async_inferior_event_token
);
139 mark_infrun_async_event_handler (void)
141 mark_async_event_handler (infrun_async_inferior_event_token
);
144 /* When set, stop the 'step' command if we enter a function which has
145 no line number information. The normal behavior is that we step
146 over such function. */
147 int step_stop_if_no_debug
= 0;
149 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
150 struct cmd_list_element
*c
, const char *value
)
152 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
155 /* proceed and normal_stop use this to notify the user when the
156 inferior stopped in a different thread than it had been running
159 static ptid_t previous_inferior_ptid
;
161 /* If set (default for legacy reasons), when following a fork, GDB
162 will detach from one of the fork branches, child or parent.
163 Exactly which branch is detached depends on 'set follow-fork-mode'
166 static int detach_fork
= 1;
168 int debug_displaced
= 0;
170 show_debug_displaced (struct ui_file
*file
, int from_tty
,
171 struct cmd_list_element
*c
, const char *value
)
173 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
176 unsigned int debug_infrun
= 0;
178 show_debug_infrun (struct ui_file
*file
, int from_tty
,
179 struct cmd_list_element
*c
, const char *value
)
181 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
185 /* Support for disabling address space randomization. */
187 int disable_randomization
= 1;
190 show_disable_randomization (struct ui_file
*file
, int from_tty
,
191 struct cmd_list_element
*c
, const char *value
)
193 if (target_supports_disable_randomization ())
194 fprintf_filtered (file
,
195 _("Disabling randomization of debuggee's "
196 "virtual address space is %s.\n"),
199 fputs_filtered (_("Disabling randomization of debuggee's "
200 "virtual address space is unsupported on\n"
201 "this platform.\n"), file
);
205 set_disable_randomization (char *args
, int from_tty
,
206 struct cmd_list_element
*c
)
208 if (!target_supports_disable_randomization ())
209 error (_("Disabling randomization of debuggee's "
210 "virtual address space is unsupported on\n"
214 /* User interface for non-stop mode. */
217 static int non_stop_1
= 0;
220 set_non_stop (char *args
, int from_tty
,
221 struct cmd_list_element
*c
)
223 if (target_has_execution
)
225 non_stop_1
= non_stop
;
226 error (_("Cannot change this setting while the inferior is running."));
229 non_stop
= non_stop_1
;
233 show_non_stop (struct ui_file
*file
, int from_tty
,
234 struct cmd_list_element
*c
, const char *value
)
236 fprintf_filtered (file
,
237 _("Controlling the inferior in non-stop mode is %s.\n"),
241 /* "Observer mode" is somewhat like a more extreme version of
242 non-stop, in which all GDB operations that might affect the
243 target's execution have been disabled. */
245 int observer_mode
= 0;
246 static int observer_mode_1
= 0;
249 set_observer_mode (char *args
, int from_tty
,
250 struct cmd_list_element
*c
)
252 if (target_has_execution
)
254 observer_mode_1
= observer_mode
;
255 error (_("Cannot change this setting while the inferior is running."));
258 observer_mode
= observer_mode_1
;
260 may_write_registers
= !observer_mode
;
261 may_write_memory
= !observer_mode
;
262 may_insert_breakpoints
= !observer_mode
;
263 may_insert_tracepoints
= !observer_mode
;
264 /* We can insert fast tracepoints in or out of observer mode,
265 but enable them if we're going into this mode. */
267 may_insert_fast_tracepoints
= 1;
268 may_stop
= !observer_mode
;
269 update_target_permissions ();
271 /* Going *into* observer mode we must force non-stop, then
272 going out we leave it that way. */
275 pagination_enabled
= 0;
276 non_stop
= non_stop_1
= 1;
280 printf_filtered (_("Observer mode is now %s.\n"),
281 (observer_mode
? "on" : "off"));
285 show_observer_mode (struct ui_file
*file
, int from_tty
,
286 struct cmd_list_element
*c
, const char *value
)
288 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
291 /* This updates the value of observer mode based on changes in
292 permissions. Note that we are deliberately ignoring the values of
293 may-write-registers and may-write-memory, since the user may have
294 reason to enable these during a session, for instance to turn on a
295 debugging-related global. */
298 update_observer_mode (void)
302 newval
= (!may_insert_breakpoints
303 && !may_insert_tracepoints
304 && may_insert_fast_tracepoints
308 /* Let the user know if things change. */
309 if (newval
!= observer_mode
)
310 printf_filtered (_("Observer mode is now %s.\n"),
311 (newval
? "on" : "off"));
313 observer_mode
= observer_mode_1
= newval
;
316 /* Tables of how to react to signals; the user sets them. */
318 static unsigned char *signal_stop
;
319 static unsigned char *signal_print
;
320 static unsigned char *signal_program
;
322 /* Table of signals that are registered with "catch signal". A
323 non-zero entry indicates that the signal is caught by some "catch
324 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
326 static unsigned char *signal_catch
;
328 /* Table of signals that the target may silently handle.
329 This is automatically determined from the flags above,
330 and simply cached here. */
331 static unsigned char *signal_pass
;
333 #define SET_SIGS(nsigs,sigs,flags) \
335 int signum = (nsigs); \
336 while (signum-- > 0) \
337 if ((sigs)[signum]) \
338 (flags)[signum] = 1; \
341 #define UNSET_SIGS(nsigs,sigs,flags) \
343 int signum = (nsigs); \
344 while (signum-- > 0) \
345 if ((sigs)[signum]) \
346 (flags)[signum] = 0; \
349 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
350 this function is to avoid exporting `signal_program'. */
353 update_signals_program_target (void)
355 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
358 /* Value to pass to target_resume() to cause all threads to resume. */
360 #define RESUME_ALL minus_one_ptid
362 /* Command list pointer for the "stop" placeholder. */
364 static struct cmd_list_element
*stop_command
;
366 /* Nonzero if we want to give control to the user when we're notified
367 of shared library events by the dynamic linker. */
368 int stop_on_solib_events
;
370 /* Enable or disable optional shared library event breakpoints
371 as appropriate when the above flag is changed. */
374 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
376 update_solib_breakpoints ();
380 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
381 struct cmd_list_element
*c
, const char *value
)
383 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
387 /* Nonzero after stop if current stack frame should be printed. */
389 static int stop_print_frame
;
391 /* This is a cached copy of the pid/waitstatus of the last event
392 returned by target_wait()/deprecated_target_wait_hook(). This
393 information is returned by get_last_target_status(). */
394 static ptid_t target_last_wait_ptid
;
395 static struct target_waitstatus target_last_waitstatus
;
397 static void context_switch (ptid_t ptid
);
399 void init_thread_stepping_state (struct thread_info
*tss
);
401 static const char follow_fork_mode_child
[] = "child";
402 static const char follow_fork_mode_parent
[] = "parent";
404 static const char *const follow_fork_mode_kind_names
[] = {
405 follow_fork_mode_child
,
406 follow_fork_mode_parent
,
410 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
412 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
413 struct cmd_list_element
*c
, const char *value
)
415 fprintf_filtered (file
,
416 _("Debugger response to a program "
417 "call of fork or vfork is \"%s\".\n"),
422 /* Handle changes to the inferior list based on the type of fork,
423 which process is being followed, and whether the other process
424 should be detached. On entry inferior_ptid must be the ptid of
425 the fork parent. At return inferior_ptid is the ptid of the
426 followed inferior. */
429 follow_fork_inferior (int follow_child
, int detach_fork
)
432 ptid_t parent_ptid
, child_ptid
;
434 has_vforked
= (inferior_thread ()->pending_follow
.kind
435 == TARGET_WAITKIND_VFORKED
);
436 parent_ptid
= inferior_ptid
;
437 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
440 && !non_stop
/* Non-stop always resumes both branches. */
441 && current_ui
->prompt_state
== PROMPT_BLOCKED
442 && !(follow_child
|| detach_fork
|| sched_multi
))
444 /* The parent stays blocked inside the vfork syscall until the
445 child execs or exits. If we don't let the child run, then
446 the parent stays blocked. If we're telling the parent to run
447 in the foreground, the user will not be able to ctrl-c to get
448 back the terminal, effectively hanging the debug session. */
449 fprintf_filtered (gdb_stderr
, _("\
450 Can not resume the parent process over vfork in the foreground while\n\
451 holding the child stopped. Try \"set detach-on-fork\" or \
452 \"set schedule-multiple\".\n"));
453 /* FIXME output string > 80 columns. */
459 /* Detach new forked process? */
462 /* Before detaching from the child, remove all breakpoints
463 from it. If we forked, then this has already been taken
464 care of by infrun.c. If we vforked however, any
465 breakpoint inserted in the parent is visible in the
466 child, even those added while stopped in a vfork
467 catchpoint. This will remove the breakpoints from the
468 parent also, but they'll be reinserted below. */
471 /* Keep breakpoints list in sync. */
472 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
475 if (info_verbose
|| debug_infrun
)
477 /* Ensure that we have a process ptid. */
478 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
480 target_terminal_ours_for_output ();
481 fprintf_filtered (gdb_stdlog
,
482 _("Detaching after %s from child %s.\n"),
483 has_vforked
? "vfork" : "fork",
484 target_pid_to_str (process_ptid
));
489 struct inferior
*parent_inf
, *child_inf
;
490 struct cleanup
*old_chain
;
492 /* Add process to GDB's tables. */
493 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
495 parent_inf
= current_inferior ();
496 child_inf
->attach_flag
= parent_inf
->attach_flag
;
497 copy_terminal_info (child_inf
, parent_inf
);
498 child_inf
->gdbarch
= parent_inf
->gdbarch
;
499 copy_inferior_target_desc_info (child_inf
, parent_inf
);
501 old_chain
= save_current_space_and_thread ();
503 inferior_ptid
= child_ptid
;
504 add_thread (inferior_ptid
);
505 set_current_inferior (child_inf
);
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
);
634 set_current_inferior (child_inf
);
636 /* If this is a vfork child, then the address-space is shared
637 with the parent. If we detached from the parent, then we can
638 reuse the parent's program/address spaces. */
639 if (has_vforked
|| detach_fork
)
641 child_inf
->pspace
= parent_pspace
;
642 child_inf
->aspace
= child_inf
->pspace
->aspace
;
646 child_inf
->aspace
= new_address_space ();
647 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
648 child_inf
->removable
= 1;
649 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
650 set_current_program_space (child_inf
->pspace
);
651 clone_program_space (child_inf
->pspace
, parent_pspace
);
653 /* Let the shared library layer (e.g., solib-svr4) learn
654 about this new process, relocate the cloned exec, pull in
655 shared libraries, and install the solib event breakpoint.
656 If a "cloned-VM" event was propagated better throughout
657 the core, this wouldn't be required. */
658 solib_create_inferior_hook (0);
662 return target_follow_fork (follow_child
, detach_fork
);
665 /* Tell the target to follow the fork we're stopped at. Returns true
666 if the inferior should be resumed; false, if the target for some
667 reason decided it's best not to resume. */
672 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
673 int should_resume
= 1;
674 struct thread_info
*tp
;
676 /* Copy user stepping state to the new inferior thread. FIXME: the
677 followed fork child thread should have a copy of most of the
678 parent thread structure's run control related fields, not just these.
679 Initialized to avoid "may be used uninitialized" warnings from gcc. */
680 struct breakpoint
*step_resume_breakpoint
= NULL
;
681 struct breakpoint
*exception_resume_breakpoint
= NULL
;
682 CORE_ADDR step_range_start
= 0;
683 CORE_ADDR step_range_end
= 0;
684 struct frame_id step_frame_id
= { 0 };
685 struct thread_fsm
*thread_fsm
= NULL
;
690 struct target_waitstatus wait_status
;
692 /* Get the last target status returned by target_wait(). */
693 get_last_target_status (&wait_ptid
, &wait_status
);
695 /* If not stopped at a fork event, then there's nothing else to
697 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
698 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
701 /* Check if we switched over from WAIT_PTID, since the event was
703 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
704 && !ptid_equal (inferior_ptid
, wait_ptid
))
706 /* We did. Switch back to WAIT_PTID thread, to tell the
707 target to follow it (in either direction). We'll
708 afterwards refuse to resume, and inform the user what
710 switch_to_thread (wait_ptid
);
715 tp
= inferior_thread ();
717 /* If there were any forks/vforks that were caught and are now to be
718 followed, then do so now. */
719 switch (tp
->pending_follow
.kind
)
721 case TARGET_WAITKIND_FORKED
:
722 case TARGET_WAITKIND_VFORKED
:
724 ptid_t parent
, child
;
726 /* If the user did a next/step, etc, over a fork call,
727 preserve the stepping state in the fork child. */
728 if (follow_child
&& should_resume
)
730 step_resume_breakpoint
= clone_momentary_breakpoint
731 (tp
->control
.step_resume_breakpoint
);
732 step_range_start
= tp
->control
.step_range_start
;
733 step_range_end
= tp
->control
.step_range_end
;
734 step_frame_id
= tp
->control
.step_frame_id
;
735 exception_resume_breakpoint
736 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
737 thread_fsm
= tp
->thread_fsm
;
739 /* For now, delete the parent's sr breakpoint, otherwise,
740 parent/child sr breakpoints are considered duplicates,
741 and the child version will not be installed. Remove
742 this when the breakpoints module becomes aware of
743 inferiors and address spaces. */
744 delete_step_resume_breakpoint (tp
);
745 tp
->control
.step_range_start
= 0;
746 tp
->control
.step_range_end
= 0;
747 tp
->control
.step_frame_id
= null_frame_id
;
748 delete_exception_resume_breakpoint (tp
);
749 tp
->thread_fsm
= NULL
;
752 parent
= inferior_ptid
;
753 child
= tp
->pending_follow
.value
.related_pid
;
755 /* Set up inferior(s) as specified by the caller, and tell the
756 target to do whatever is necessary to follow either parent
758 if (follow_fork_inferior (follow_child
, detach_fork
))
760 /* Target refused to follow, or there's some other reason
761 we shouldn't resume. */
766 /* This pending follow fork event is now handled, one way
767 or another. The previous selected thread may be gone
768 from the lists by now, but if it is still around, need
769 to clear the pending follow request. */
770 tp
= find_thread_ptid (parent
);
772 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
774 /* This makes sure we don't try to apply the "Switched
775 over from WAIT_PID" logic above. */
776 nullify_last_target_wait_ptid ();
778 /* If we followed the child, switch to it... */
781 switch_to_thread (child
);
783 /* ... and preserve the stepping state, in case the
784 user was stepping over the fork call. */
787 tp
= inferior_thread ();
788 tp
->control
.step_resume_breakpoint
789 = step_resume_breakpoint
;
790 tp
->control
.step_range_start
= step_range_start
;
791 tp
->control
.step_range_end
= step_range_end
;
792 tp
->control
.step_frame_id
= step_frame_id
;
793 tp
->control
.exception_resume_breakpoint
794 = exception_resume_breakpoint
;
795 tp
->thread_fsm
= thread_fsm
;
799 /* If we get here, it was because we're trying to
800 resume from a fork catchpoint, but, the user
801 has switched threads away from the thread that
802 forked. In that case, the resume command
803 issued is most likely not applicable to the
804 child, so just warn, and refuse to resume. */
805 warning (_("Not resuming: switched threads "
806 "before following fork child."));
809 /* Reset breakpoints in the child as appropriate. */
810 follow_inferior_reset_breakpoints ();
813 switch_to_thread (parent
);
817 case TARGET_WAITKIND_SPURIOUS
:
818 /* Nothing to follow. */
821 internal_error (__FILE__
, __LINE__
,
822 "Unexpected pending_follow.kind %d\n",
823 tp
->pending_follow
.kind
);
827 return should_resume
;
831 follow_inferior_reset_breakpoints (void)
833 struct thread_info
*tp
= inferior_thread ();
835 /* Was there a step_resume breakpoint? (There was if the user
836 did a "next" at the fork() call.) If so, explicitly reset its
837 thread number. Cloned step_resume breakpoints are disabled on
838 creation, so enable it here now that it is associated with the
841 step_resumes are a form of bp that are made to be per-thread.
842 Since we created the step_resume bp when the parent process
843 was being debugged, and now are switching to the child process,
844 from the breakpoint package's viewpoint, that's a switch of
845 "threads". We must update the bp's notion of which thread
846 it is for, or it'll be ignored when it triggers. */
848 if (tp
->control
.step_resume_breakpoint
)
850 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
851 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
854 /* Treat exception_resume breakpoints like step_resume breakpoints. */
855 if (tp
->control
.exception_resume_breakpoint
)
857 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
858 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
861 /* Reinsert all breakpoints in the child. The user may have set
862 breakpoints after catching the fork, in which case those
863 were never set in the child, but only in the parent. This makes
864 sure the inserted breakpoints match the breakpoint list. */
866 breakpoint_re_set ();
867 insert_breakpoints ();
870 /* The child has exited or execed: resume threads of the parent the
871 user wanted to be executing. */
874 proceed_after_vfork_done (struct thread_info
*thread
,
877 int pid
= * (int *) arg
;
879 if (ptid_get_pid (thread
->ptid
) == pid
880 && is_running (thread
->ptid
)
881 && !is_executing (thread
->ptid
)
882 && !thread
->stop_requested
883 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
886 fprintf_unfiltered (gdb_stdlog
,
887 "infrun: resuming vfork parent thread %s\n",
888 target_pid_to_str (thread
->ptid
));
890 switch_to_thread (thread
->ptid
);
891 clear_proceed_status (0);
892 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
898 /* Called whenever we notice an exec or exit event, to handle
899 detaching or resuming a vfork parent. */
902 handle_vfork_child_exec_or_exit (int exec
)
904 struct inferior
*inf
= current_inferior ();
906 if (inf
->vfork_parent
)
908 int resume_parent
= -1;
910 /* This exec or exit marks the end of the shared memory region
911 between the parent and the child. If the user wanted to
912 detach from the parent, now is the time. */
914 if (inf
->vfork_parent
->pending_detach
)
916 struct thread_info
*tp
;
917 struct cleanup
*old_chain
;
918 struct program_space
*pspace
;
919 struct address_space
*aspace
;
921 /* follow-fork child, detach-on-fork on. */
923 inf
->vfork_parent
->pending_detach
= 0;
927 /* If we're handling a child exit, then inferior_ptid
928 points at the inferior's pid, not to a thread. */
929 old_chain
= save_inferior_ptid ();
930 save_current_program_space ();
931 save_current_inferior ();
934 old_chain
= save_current_space_and_thread ();
936 /* We're letting loose of the parent. */
937 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
938 switch_to_thread (tp
->ptid
);
940 /* We're about to detach from the parent, which implicitly
941 removes breakpoints from its address space. There's a
942 catch here: we want to reuse the spaces for the child,
943 but, parent/child are still sharing the pspace at this
944 point, although the exec in reality makes the kernel give
945 the child a fresh set of new pages. The problem here is
946 that the breakpoints module being unaware of this, would
947 likely chose the child process to write to the parent
948 address space. Swapping the child temporarily away from
949 the spaces has the desired effect. Yes, this is "sort
952 pspace
= inf
->pspace
;
953 aspace
= inf
->aspace
;
957 if (debug_infrun
|| info_verbose
)
959 target_terminal_ours_for_output ();
963 fprintf_filtered (gdb_stdlog
,
964 _("Detaching vfork parent process "
965 "%d after child exec.\n"),
966 inf
->vfork_parent
->pid
);
970 fprintf_filtered (gdb_stdlog
,
971 _("Detaching vfork parent process "
972 "%d after child exit.\n"),
973 inf
->vfork_parent
->pid
);
977 target_detach (NULL
, 0);
980 inf
->pspace
= pspace
;
981 inf
->aspace
= aspace
;
983 do_cleanups (old_chain
);
987 /* We're staying attached to the parent, so, really give the
988 child a new address space. */
989 inf
->pspace
= add_program_space (maybe_new_address_space ());
990 inf
->aspace
= inf
->pspace
->aspace
;
992 set_current_program_space (inf
->pspace
);
994 resume_parent
= inf
->vfork_parent
->pid
;
996 /* Break the bonds. */
997 inf
->vfork_parent
->vfork_child
= NULL
;
1001 struct cleanup
*old_chain
;
1002 struct program_space
*pspace
;
1004 /* If this is a vfork child exiting, then the pspace and
1005 aspaces were shared with the parent. Since we're
1006 reporting the process exit, we'll be mourning all that is
1007 found in the address space, and switching to null_ptid,
1008 preparing to start a new inferior. But, since we don't
1009 want to clobber the parent's address/program spaces, we
1010 go ahead and create a new one for this exiting
1013 /* Switch to null_ptid, so that clone_program_space doesn't want
1014 to read the selected frame of a dead process. */
1015 old_chain
= save_inferior_ptid ();
1016 inferior_ptid
= null_ptid
;
1018 /* This inferior is dead, so avoid giving the breakpoints
1019 module the option to write through to it (cloning a
1020 program space resets breakpoints). */
1023 pspace
= add_program_space (maybe_new_address_space ());
1024 set_current_program_space (pspace
);
1026 inf
->symfile_flags
= SYMFILE_NO_READ
;
1027 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1028 inf
->pspace
= pspace
;
1029 inf
->aspace
= pspace
->aspace
;
1031 /* Put back inferior_ptid. We'll continue mourning this
1033 do_cleanups (old_chain
);
1035 resume_parent
= inf
->vfork_parent
->pid
;
1036 /* Break the bonds. */
1037 inf
->vfork_parent
->vfork_child
= NULL
;
1040 inf
->vfork_parent
= NULL
;
1042 gdb_assert (current_program_space
== inf
->pspace
);
1044 if (non_stop
&& resume_parent
!= -1)
1046 /* If the user wanted the parent to be running, let it go
1048 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1051 fprintf_unfiltered (gdb_stdlog
,
1052 "infrun: resuming vfork parent process %d\n",
1055 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1057 do_cleanups (old_chain
);
1062 /* Enum strings for "set|show follow-exec-mode". */
1064 static const char follow_exec_mode_new
[] = "new";
1065 static const char follow_exec_mode_same
[] = "same";
1066 static const char *const follow_exec_mode_names
[] =
1068 follow_exec_mode_new
,
1069 follow_exec_mode_same
,
1073 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1075 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1076 struct cmd_list_element
*c
, const char *value
)
1078 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1081 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1084 follow_exec (ptid_t ptid
, char *exec_file_target
)
1086 struct thread_info
*th
, *tmp
;
1087 struct inferior
*inf
= current_inferior ();
1088 int pid
= ptid_get_pid (ptid
);
1089 ptid_t process_ptid
;
1090 char *exec_file_host
;
1091 struct cleanup
*old_chain
;
1093 /* This is an exec event that we actually wish to pay attention to.
1094 Refresh our symbol table to the newly exec'd program, remove any
1095 momentary bp's, etc.
1097 If there are breakpoints, they aren't really inserted now,
1098 since the exec() transformed our inferior into a fresh set
1101 We want to preserve symbolic breakpoints on the list, since
1102 we have hopes that they can be reset after the new a.out's
1103 symbol table is read.
1105 However, any "raw" breakpoints must be removed from the list
1106 (e.g., the solib bp's), since their address is probably invalid
1109 And, we DON'T want to call delete_breakpoints() here, since
1110 that may write the bp's "shadow contents" (the instruction
1111 value that was overwritten witha TRAP instruction). Since
1112 we now have a new a.out, those shadow contents aren't valid. */
1114 mark_breakpoints_out ();
1116 /* The target reports the exec event to the main thread, even if
1117 some other thread does the exec, and even if the main thread was
1118 stopped or already gone. We may still have non-leader threads of
1119 the process on our list. E.g., on targets that don't have thread
1120 exit events (like remote); or on native Linux in non-stop mode if
1121 there were only two threads in the inferior and the non-leader
1122 one is the one that execs (and nothing forces an update of the
1123 thread list up to here). When debugging remotely, it's best to
1124 avoid extra traffic, when possible, so avoid syncing the thread
1125 list with the target, and instead go ahead and delete all threads
1126 of the process but one that reported the event. Note this must
1127 be done before calling update_breakpoints_after_exec, as
1128 otherwise clearing the threads' resources would reference stale
1129 thread breakpoints -- it may have been one of these threads that
1130 stepped across the exec. We could just clear their stepping
1131 states, but as long as we're iterating, might as well delete
1132 them. Deleting them now rather than at the next user-visible
1133 stop provides a nicer sequence of events for user and MI
1135 ALL_THREADS_SAFE (th
, tmp
)
1136 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1137 delete_thread (th
->ptid
);
1139 /* We also need to clear any left over stale state for the
1140 leader/event thread. E.g., if there was any step-resume
1141 breakpoint or similar, it's gone now. We cannot truly
1142 step-to-next statement through an exec(). */
1143 th
= inferior_thread ();
1144 th
->control
.step_resume_breakpoint
= NULL
;
1145 th
->control
.exception_resume_breakpoint
= NULL
;
1146 th
->control
.single_step_breakpoints
= NULL
;
1147 th
->control
.step_range_start
= 0;
1148 th
->control
.step_range_end
= 0;
1150 /* The user may have had the main thread held stopped in the
1151 previous image (e.g., schedlock on, or non-stop). Release
1153 th
->stop_requested
= 0;
1155 update_breakpoints_after_exec ();
1157 /* What is this a.out's name? */
1158 process_ptid
= pid_to_ptid (pid
);
1159 printf_unfiltered (_("%s is executing new program: %s\n"),
1160 target_pid_to_str (process_ptid
),
1163 /* We've followed the inferior through an exec. Therefore, the
1164 inferior has essentially been killed & reborn. */
1166 gdb_flush (gdb_stdout
);
1168 breakpoint_init_inferior (inf_execd
);
1170 exec_file_host
= exec_file_find (exec_file_target
, NULL
);
1171 old_chain
= make_cleanup (xfree
, exec_file_host
);
1173 /* If we were unable to map the executable target pathname onto a host
1174 pathname, tell the user that. Otherwise GDB's subsequent behavior
1175 is confusing. Maybe it would even be better to stop at this point
1176 so that the user can specify a file manually before continuing. */
1177 if (exec_file_host
== NULL
)
1178 warning (_("Could not load symbols for executable %s.\n"
1179 "Do you need \"set sysroot\"?"),
1182 /* Reset the shared library package. This ensures that we get a
1183 shlib event when the child reaches "_start", at which point the
1184 dld will have had a chance to initialize the child. */
1185 /* Also, loading a symbol file below may trigger symbol lookups, and
1186 we don't want those to be satisfied by the libraries of the
1187 previous incarnation of this process. */
1188 no_shared_libraries (NULL
, 0);
1190 if (follow_exec_mode_string
== follow_exec_mode_new
)
1192 /* The user wants to keep the old inferior and program spaces
1193 around. Create a new fresh one, and switch to it. */
1195 /* Do exit processing for the original inferior before adding
1196 the new inferior so we don't have two active inferiors with
1197 the same ptid, which can confuse find_inferior_ptid. */
1198 exit_inferior_num_silent (current_inferior ()->num
);
1200 inf
= add_inferior_with_spaces ();
1202 target_follow_exec (inf
, exec_file_target
);
1204 set_current_inferior (inf
);
1205 set_current_program_space (inf
->pspace
);
1210 /* The old description may no longer be fit for the new image.
1211 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1212 old description; we'll read a new one below. No need to do
1213 this on "follow-exec-mode new", as the old inferior stays
1214 around (its description is later cleared/refetched on
1216 target_clear_description ();
1219 gdb_assert (current_program_space
== inf
->pspace
);
1221 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1222 because the proper displacement for a PIE (Position Independent
1223 Executable) main symbol file will only be computed by
1224 solib_create_inferior_hook below. breakpoint_re_set would fail
1225 to insert the breakpoints with the zero displacement. */
1226 try_open_exec_file (exec_file_host
, inf
, SYMFILE_DEFER_BP_RESET
);
1228 do_cleanups (old_chain
);
1230 /* If the target can specify a description, read it. Must do this
1231 after flipping to the new executable (because the target supplied
1232 description must be compatible with the executable's
1233 architecture, and the old executable may e.g., be 32-bit, while
1234 the new one 64-bit), and before anything involving memory or
1236 target_find_description ();
1238 solib_create_inferior_hook (0);
1240 jit_inferior_created_hook ();
1242 breakpoint_re_set ();
1244 /* Reinsert all breakpoints. (Those which were symbolic have
1245 been reset to the proper address in the new a.out, thanks
1246 to symbol_file_command...). */
1247 insert_breakpoints ();
1249 /* The next resume of this inferior should bring it to the shlib
1250 startup breakpoints. (If the user had also set bp's on
1251 "main" from the old (parent) process, then they'll auto-
1252 matically get reset there in the new process.). */
1255 /* The queue of threads that need to do a step-over operation to get
1256 past e.g., a breakpoint. What technique is used to step over the
1257 breakpoint/watchpoint does not matter -- all threads end up in the
1258 same queue, to maintain rough temporal order of execution, in order
1259 to avoid starvation, otherwise, we could e.g., find ourselves
1260 constantly stepping the same couple threads past their breakpoints
1261 over and over, if the single-step finish fast enough. */
1262 struct thread_info
*step_over_queue_head
;
1264 /* Bit flags indicating what the thread needs to step over. */
1266 enum step_over_what_flag
1268 /* Step over a breakpoint. */
1269 STEP_OVER_BREAKPOINT
= 1,
1271 /* Step past a non-continuable watchpoint, in order to let the
1272 instruction execute so we can evaluate the watchpoint
1274 STEP_OVER_WATCHPOINT
= 2
1276 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1278 /* Info about an instruction that is being stepped over. */
1280 struct step_over_info
1282 /* If we're stepping past a breakpoint, this is the address space
1283 and address of the instruction the breakpoint is set at. We'll
1284 skip inserting all breakpoints here. Valid iff ASPACE is
1286 struct address_space
*aspace
;
1289 /* The instruction being stepped over triggers a nonsteppable
1290 watchpoint. If true, we'll skip inserting watchpoints. */
1291 int nonsteppable_watchpoint_p
;
1293 /* The thread's global number. */
1297 /* The step-over info of the location that is being stepped over.
1299 Note that with async/breakpoint always-inserted mode, a user might
1300 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1301 being stepped over. As setting a new breakpoint inserts all
1302 breakpoints, we need to make sure the breakpoint being stepped over
1303 isn't inserted then. We do that by only clearing the step-over
1304 info when the step-over is actually finished (or aborted).
1306 Presently GDB can only step over one breakpoint at any given time.
1307 Given threads that can't run code in the same address space as the
1308 breakpoint's can't really miss the breakpoint, GDB could be taught
1309 to step-over at most one breakpoint per address space (so this info
1310 could move to the address space object if/when GDB is extended).
1311 The set of breakpoints being stepped over will normally be much
1312 smaller than the set of all breakpoints, so a flag in the
1313 breakpoint location structure would be wasteful. A separate list
1314 also saves complexity and run-time, as otherwise we'd have to go
1315 through all breakpoint locations clearing their flag whenever we
1316 start a new sequence. Similar considerations weigh against storing
1317 this info in the thread object. Plus, not all step overs actually
1318 have breakpoint locations -- e.g., stepping past a single-step
1319 breakpoint, or stepping to complete a non-continuable
1321 static struct step_over_info step_over_info
;
1323 /* Record the address of the breakpoint/instruction we're currently
1325 N.B. We record the aspace and address now, instead of say just the thread,
1326 because when we need the info later the thread may be running. */
1329 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1330 int nonsteppable_watchpoint_p
,
1333 step_over_info
.aspace
= aspace
;
1334 step_over_info
.address
= address
;
1335 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1336 step_over_info
.thread
= thread
;
1339 /* Called when we're not longer stepping over a breakpoint / an
1340 instruction, so all breakpoints are free to be (re)inserted. */
1343 clear_step_over_info (void)
1346 fprintf_unfiltered (gdb_stdlog
,
1347 "infrun: clear_step_over_info\n");
1348 step_over_info
.aspace
= NULL
;
1349 step_over_info
.address
= 0;
1350 step_over_info
.nonsteppable_watchpoint_p
= 0;
1351 step_over_info
.thread
= -1;
1357 stepping_past_instruction_at (struct address_space
*aspace
,
1360 return (step_over_info
.aspace
!= NULL
1361 && breakpoint_address_match (aspace
, address
,
1362 step_over_info
.aspace
,
1363 step_over_info
.address
));
1369 thread_is_stepping_over_breakpoint (int thread
)
1371 return (step_over_info
.thread
!= -1
1372 && thread
== step_over_info
.thread
);
1378 stepping_past_nonsteppable_watchpoint (void)
1380 return step_over_info
.nonsteppable_watchpoint_p
;
1383 /* Returns true if step-over info is valid. */
1386 step_over_info_valid_p (void)
1388 return (step_over_info
.aspace
!= NULL
1389 || stepping_past_nonsteppable_watchpoint ());
1393 /* Displaced stepping. */
1395 /* In non-stop debugging mode, we must take special care to manage
1396 breakpoints properly; in particular, the traditional strategy for
1397 stepping a thread past a breakpoint it has hit is unsuitable.
1398 'Displaced stepping' is a tactic for stepping one thread past a
1399 breakpoint it has hit while ensuring that other threads running
1400 concurrently will hit the breakpoint as they should.
1402 The traditional way to step a thread T off a breakpoint in a
1403 multi-threaded program in all-stop mode is as follows:
1405 a0) Initially, all threads are stopped, and breakpoints are not
1407 a1) We single-step T, leaving breakpoints uninserted.
1408 a2) We insert breakpoints, and resume all threads.
1410 In non-stop debugging, however, this strategy is unsuitable: we
1411 don't want to have to stop all threads in the system in order to
1412 continue or step T past a breakpoint. Instead, we use displaced
1415 n0) Initially, T is stopped, other threads are running, and
1416 breakpoints are inserted.
1417 n1) We copy the instruction "under" the breakpoint to a separate
1418 location, outside the main code stream, making any adjustments
1419 to the instruction, register, and memory state as directed by
1421 n2) We single-step T over the instruction at its new location.
1422 n3) We adjust the resulting register and memory state as directed
1423 by T's architecture. This includes resetting T's PC to point
1424 back into the main instruction stream.
1427 This approach depends on the following gdbarch methods:
1429 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1430 indicate where to copy the instruction, and how much space must
1431 be reserved there. We use these in step n1.
1433 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1434 address, and makes any necessary adjustments to the instruction,
1435 register contents, and memory. We use this in step n1.
1437 - gdbarch_displaced_step_fixup adjusts registers and memory after
1438 we have successfuly single-stepped the instruction, to yield the
1439 same effect the instruction would have had if we had executed it
1440 at its original address. We use this in step n3.
1442 - gdbarch_displaced_step_free_closure provides cleanup.
1444 The gdbarch_displaced_step_copy_insn and
1445 gdbarch_displaced_step_fixup functions must be written so that
1446 copying an instruction with gdbarch_displaced_step_copy_insn,
1447 single-stepping across the copied instruction, and then applying
1448 gdbarch_displaced_insn_fixup should have the same effects on the
1449 thread's memory and registers as stepping the instruction in place
1450 would have. Exactly which responsibilities fall to the copy and
1451 which fall to the fixup is up to the author of those functions.
1453 See the comments in gdbarch.sh for details.
1455 Note that displaced stepping and software single-step cannot
1456 currently be used in combination, although with some care I think
1457 they could be made to. Software single-step works by placing
1458 breakpoints on all possible subsequent instructions; if the
1459 displaced instruction is a PC-relative jump, those breakpoints
1460 could fall in very strange places --- on pages that aren't
1461 executable, or at addresses that are not proper instruction
1462 boundaries. (We do generally let other threads run while we wait
1463 to hit the software single-step breakpoint, and they might
1464 encounter such a corrupted instruction.) One way to work around
1465 this would be to have gdbarch_displaced_step_copy_insn fully
1466 simulate the effect of PC-relative instructions (and return NULL)
1467 on architectures that use software single-stepping.
1469 In non-stop mode, we can have independent and simultaneous step
1470 requests, so more than one thread may need to simultaneously step
1471 over a breakpoint. The current implementation assumes there is
1472 only one scratch space per process. In this case, we have to
1473 serialize access to the scratch space. If thread A wants to step
1474 over a breakpoint, but we are currently waiting for some other
1475 thread to complete a displaced step, we leave thread A stopped and
1476 place it in the displaced_step_request_queue. Whenever a displaced
1477 step finishes, we pick the next thread in the queue and start a new
1478 displaced step operation on it. See displaced_step_prepare and
1479 displaced_step_fixup for details. */
1481 /* Per-inferior displaced stepping state. */
1482 struct displaced_step_inferior_state
1484 /* Pointer to next in linked list. */
1485 struct displaced_step_inferior_state
*next
;
1487 /* The process this displaced step state refers to. */
1490 /* True if preparing a displaced step ever failed. If so, we won't
1491 try displaced stepping for this inferior again. */
1494 /* If this is not null_ptid, this is the thread carrying out a
1495 displaced single-step in process PID. This thread's state will
1496 require fixing up once it has completed its step. */
1499 /* The architecture the thread had when we stepped it. */
1500 struct gdbarch
*step_gdbarch
;
1502 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1503 for post-step cleanup. */
1504 struct displaced_step_closure
*step_closure
;
1506 /* The address of the original instruction, and the copy we
1508 CORE_ADDR step_original
, step_copy
;
1510 /* Saved contents of copy area. */
1511 gdb_byte
*step_saved_copy
;
1514 /* The list of states of processes involved in displaced stepping
1516 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1518 /* Get the displaced stepping state of process PID. */
1520 static struct displaced_step_inferior_state
*
1521 get_displaced_stepping_state (int pid
)
1523 struct displaced_step_inferior_state
*state
;
1525 for (state
= displaced_step_inferior_states
;
1527 state
= state
->next
)
1528 if (state
->pid
== pid
)
1534 /* Returns true if any inferior has a thread doing a displaced
1538 displaced_step_in_progress_any_inferior (void)
1540 struct displaced_step_inferior_state
*state
;
1542 for (state
= displaced_step_inferior_states
;
1544 state
= state
->next
)
1545 if (!ptid_equal (state
->step_ptid
, null_ptid
))
1551 /* Return true if thread represented by PTID is doing a displaced
1555 displaced_step_in_progress_thread (ptid_t ptid
)
1557 struct displaced_step_inferior_state
*displaced
;
1559 gdb_assert (!ptid_equal (ptid
, null_ptid
));
1561 displaced
= get_displaced_stepping_state (ptid_get_pid (ptid
));
1563 return (displaced
!= NULL
&& ptid_equal (displaced
->step_ptid
, ptid
));
1566 /* Return true if process PID has a thread doing a displaced step. */
1569 displaced_step_in_progress (int pid
)
1571 struct displaced_step_inferior_state
*displaced
;
1573 displaced
= get_displaced_stepping_state (pid
);
1574 if (displaced
!= NULL
&& !ptid_equal (displaced
->step_ptid
, null_ptid
))
1580 /* Add a new displaced stepping state for process PID to the displaced
1581 stepping state list, or return a pointer to an already existing
1582 entry, if it already exists. Never returns NULL. */
1584 static struct displaced_step_inferior_state
*
1585 add_displaced_stepping_state (int pid
)
1587 struct displaced_step_inferior_state
*state
;
1589 for (state
= displaced_step_inferior_states
;
1591 state
= state
->next
)
1592 if (state
->pid
== pid
)
1595 state
= XCNEW (struct displaced_step_inferior_state
);
1597 state
->next
= displaced_step_inferior_states
;
1598 displaced_step_inferior_states
= state
;
1603 /* If inferior is in displaced stepping, and ADDR equals to starting address
1604 of copy area, return corresponding displaced_step_closure. Otherwise,
1607 struct displaced_step_closure
*
1608 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1610 struct displaced_step_inferior_state
*displaced
1611 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1613 /* If checking the mode of displaced instruction in copy area. */
1614 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1615 && (displaced
->step_copy
== addr
))
1616 return displaced
->step_closure
;
1621 /* Remove the displaced stepping state of process PID. */
1624 remove_displaced_stepping_state (int pid
)
1626 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1628 gdb_assert (pid
!= 0);
1630 it
= displaced_step_inferior_states
;
1631 prev_next_p
= &displaced_step_inferior_states
;
1636 *prev_next_p
= it
->next
;
1641 prev_next_p
= &it
->next
;
1647 infrun_inferior_exit (struct inferior
*inf
)
1649 remove_displaced_stepping_state (inf
->pid
);
1652 /* If ON, and the architecture supports it, GDB will use displaced
1653 stepping to step over breakpoints. If OFF, or if the architecture
1654 doesn't support it, GDB will instead use the traditional
1655 hold-and-step approach. If AUTO (which is the default), GDB will
1656 decide which technique to use to step over breakpoints depending on
1657 which of all-stop or non-stop mode is active --- displaced stepping
1658 in non-stop mode; hold-and-step in all-stop mode. */
1660 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1663 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1664 struct cmd_list_element
*c
,
1667 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1668 fprintf_filtered (file
,
1669 _("Debugger's willingness to use displaced stepping "
1670 "to step over breakpoints is %s (currently %s).\n"),
1671 value
, target_is_non_stop_p () ? "on" : "off");
1673 fprintf_filtered (file
,
1674 _("Debugger's willingness to use displaced stepping "
1675 "to step over breakpoints is %s.\n"), value
);
1678 /* Return non-zero if displaced stepping can/should be used to step
1679 over breakpoints of thread TP. */
1682 use_displaced_stepping (struct thread_info
*tp
)
1684 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
1685 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1686 struct displaced_step_inferior_state
*displaced_state
;
1688 displaced_state
= get_displaced_stepping_state (ptid_get_pid (tp
->ptid
));
1690 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1691 && target_is_non_stop_p ())
1692 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1693 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1694 && find_record_target () == NULL
1695 && (displaced_state
== NULL
1696 || !displaced_state
->failed_before
));
1699 /* Clean out any stray displaced stepping state. */
1701 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1703 /* Indicate that there is no cleanup pending. */
1704 displaced
->step_ptid
= null_ptid
;
1706 if (displaced
->step_closure
)
1708 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1709 displaced
->step_closure
);
1710 displaced
->step_closure
= NULL
;
1715 displaced_step_clear_cleanup (void *arg
)
1717 struct displaced_step_inferior_state
*state
1718 = (struct displaced_step_inferior_state
*) arg
;
1720 displaced_step_clear (state
);
1723 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1725 displaced_step_dump_bytes (struct ui_file
*file
,
1726 const gdb_byte
*buf
,
1731 for (i
= 0; i
< len
; i
++)
1732 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1733 fputs_unfiltered ("\n", file
);
1736 /* Prepare to single-step, using displaced stepping.
1738 Note that we cannot use displaced stepping when we have a signal to
1739 deliver. If we have a signal to deliver and an instruction to step
1740 over, then after the step, there will be no indication from the
1741 target whether the thread entered a signal handler or ignored the
1742 signal and stepped over the instruction successfully --- both cases
1743 result in a simple SIGTRAP. In the first case we mustn't do a
1744 fixup, and in the second case we must --- but we can't tell which.
1745 Comments in the code for 'random signals' in handle_inferior_event
1746 explain how we handle this case instead.
1748 Returns 1 if preparing was successful -- this thread is going to be
1749 stepped now; 0 if displaced stepping this thread got queued; or -1
1750 if this instruction can't be displaced stepped. */
1753 displaced_step_prepare_throw (ptid_t ptid
)
1755 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1756 struct thread_info
*tp
= find_thread_ptid (ptid
);
1757 struct regcache
*regcache
= get_thread_regcache (ptid
);
1758 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1759 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1760 CORE_ADDR original
, copy
;
1762 struct displaced_step_closure
*closure
;
1763 struct displaced_step_inferior_state
*displaced
;
1766 /* We should never reach this function if the architecture does not
1767 support displaced stepping. */
1768 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1770 /* Nor if the thread isn't meant to step over a breakpoint. */
1771 gdb_assert (tp
->control
.trap_expected
);
1773 /* Disable range stepping while executing in the scratch pad. We
1774 want a single-step even if executing the displaced instruction in
1775 the scratch buffer lands within the stepping range (e.g., a
1777 tp
->control
.may_range_step
= 0;
1779 /* We have to displaced step one thread at a time, as we only have
1780 access to a single scratch space per inferior. */
1782 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1784 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1786 /* Already waiting for a displaced step to finish. Defer this
1787 request and place in queue. */
1789 if (debug_displaced
)
1790 fprintf_unfiltered (gdb_stdlog
,
1791 "displaced: deferring step of %s\n",
1792 target_pid_to_str (ptid
));
1794 thread_step_over_chain_enqueue (tp
);
1799 if (debug_displaced
)
1800 fprintf_unfiltered (gdb_stdlog
,
1801 "displaced: stepping %s now\n",
1802 target_pid_to_str (ptid
));
1805 displaced_step_clear (displaced
);
1807 old_cleanups
= save_inferior_ptid ();
1808 inferior_ptid
= ptid
;
1810 original
= regcache_read_pc (regcache
);
1812 copy
= gdbarch_displaced_step_location (gdbarch
);
1813 len
= gdbarch_max_insn_length (gdbarch
);
1815 if (breakpoint_in_range_p (aspace
, copy
, len
))
1817 /* There's a breakpoint set in the scratch pad location range
1818 (which is usually around the entry point). We'd either
1819 install it before resuming, which would overwrite/corrupt the
1820 scratch pad, or if it was already inserted, this displaced
1821 step would overwrite it. The latter is OK in the sense that
1822 we already assume that no thread is going to execute the code
1823 in the scratch pad range (after initial startup) anyway, but
1824 the former is unacceptable. Simply punt and fallback to
1825 stepping over this breakpoint in-line. */
1826 if (debug_displaced
)
1828 fprintf_unfiltered (gdb_stdlog
,
1829 "displaced: breakpoint set in scratch pad. "
1830 "Stepping over breakpoint in-line instead.\n");
1833 do_cleanups (old_cleanups
);
1837 /* Save the original contents of the copy area. */
1838 displaced
->step_saved_copy
= (gdb_byte
*) xmalloc (len
);
1839 ignore_cleanups
= make_cleanup (free_current_contents
,
1840 &displaced
->step_saved_copy
);
1841 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1843 throw_error (MEMORY_ERROR
,
1844 _("Error accessing memory address %s (%s) for "
1845 "displaced-stepping scratch space."),
1846 paddress (gdbarch
, copy
), safe_strerror (status
));
1847 if (debug_displaced
)
1849 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1850 paddress (gdbarch
, copy
));
1851 displaced_step_dump_bytes (gdb_stdlog
,
1852 displaced
->step_saved_copy
,
1856 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1857 original
, copy
, regcache
);
1858 if (closure
== NULL
)
1860 /* The architecture doesn't know how or want to displaced step
1861 this instruction or instruction sequence. Fallback to
1862 stepping over the breakpoint in-line. */
1863 do_cleanups (old_cleanups
);
1867 /* Save the information we need to fix things up if the step
1869 displaced
->step_ptid
= ptid
;
1870 displaced
->step_gdbarch
= gdbarch
;
1871 displaced
->step_closure
= closure
;
1872 displaced
->step_original
= original
;
1873 displaced
->step_copy
= copy
;
1875 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1877 /* Resume execution at the copy. */
1878 regcache_write_pc (regcache
, copy
);
1880 discard_cleanups (ignore_cleanups
);
1882 do_cleanups (old_cleanups
);
1884 if (debug_displaced
)
1885 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1886 paddress (gdbarch
, copy
));
1891 /* Wrapper for displaced_step_prepare_throw that disabled further
1892 attempts at displaced stepping if we get a memory error. */
1895 displaced_step_prepare (ptid_t ptid
)
1901 prepared
= displaced_step_prepare_throw (ptid
);
1903 CATCH (ex
, RETURN_MASK_ERROR
)
1905 struct displaced_step_inferior_state
*displaced_state
;
1907 if (ex
.error
!= MEMORY_ERROR
1908 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1909 throw_exception (ex
);
1913 fprintf_unfiltered (gdb_stdlog
,
1914 "infrun: disabling displaced stepping: %s\n",
1918 /* Be verbose if "set displaced-stepping" is "on", silent if
1920 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1922 warning (_("disabling displaced stepping: %s"),
1926 /* Disable further displaced stepping attempts. */
1928 = get_displaced_stepping_state (ptid_get_pid (ptid
));
1929 displaced_state
->failed_before
= 1;
1937 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1938 const gdb_byte
*myaddr
, int len
)
1940 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1942 inferior_ptid
= ptid
;
1943 write_memory (memaddr
, myaddr
, len
);
1944 do_cleanups (ptid_cleanup
);
1947 /* Restore the contents of the copy area for thread PTID. */
1950 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1953 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1955 write_memory_ptid (ptid
, displaced
->step_copy
,
1956 displaced
->step_saved_copy
, len
);
1957 if (debug_displaced
)
1958 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1959 target_pid_to_str (ptid
),
1960 paddress (displaced
->step_gdbarch
,
1961 displaced
->step_copy
));
1964 /* If we displaced stepped an instruction successfully, adjust
1965 registers and memory to yield the same effect the instruction would
1966 have had if we had executed it at its original address, and return
1967 1. If the instruction didn't complete, relocate the PC and return
1968 -1. If the thread wasn't displaced stepping, return 0. */
1971 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1973 struct cleanup
*old_cleanups
;
1974 struct displaced_step_inferior_state
*displaced
1975 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1978 /* Was any thread of this process doing a displaced step? */
1979 if (displaced
== NULL
)
1982 /* Was this event for the pid we displaced? */
1983 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1984 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1987 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1989 displaced_step_restore (displaced
, displaced
->step_ptid
);
1991 /* Fixup may need to read memory/registers. Switch to the thread
1992 that we're fixing up. Also, target_stopped_by_watchpoint checks
1993 the current thread. */
1994 switch_to_thread (event_ptid
);
1996 /* Did the instruction complete successfully? */
1997 if (signal
== GDB_SIGNAL_TRAP
1998 && !(target_stopped_by_watchpoint ()
1999 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
2000 || target_have_steppable_watchpoint
)))
2002 /* Fix up the resulting state. */
2003 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
2004 displaced
->step_closure
,
2005 displaced
->step_original
,
2006 displaced
->step_copy
,
2007 get_thread_regcache (displaced
->step_ptid
));
2012 /* Since the instruction didn't complete, all we can do is
2014 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
2015 CORE_ADDR pc
= regcache_read_pc (regcache
);
2017 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
2018 regcache_write_pc (regcache
, pc
);
2022 do_cleanups (old_cleanups
);
2024 displaced
->step_ptid
= null_ptid
;
2029 /* Data to be passed around while handling an event. This data is
2030 discarded between events. */
2031 struct execution_control_state
2034 /* The thread that got the event, if this was a thread event; NULL
2036 struct thread_info
*event_thread
;
2038 struct target_waitstatus ws
;
2039 int stop_func_filled_in
;
2040 CORE_ADDR stop_func_start
;
2041 CORE_ADDR stop_func_end
;
2042 const char *stop_func_name
;
2045 /* True if the event thread hit the single-step breakpoint of
2046 another thread. Thus the event doesn't cause a stop, the thread
2047 needs to be single-stepped past the single-step breakpoint before
2048 we can switch back to the original stepping thread. */
2049 int hit_singlestep_breakpoint
;
2052 /* Clear ECS and set it to point at TP. */
2055 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
2057 memset (ecs
, 0, sizeof (*ecs
));
2058 ecs
->event_thread
= tp
;
2059 ecs
->ptid
= tp
->ptid
;
2062 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
2063 static void prepare_to_wait (struct execution_control_state
*ecs
);
2064 static int keep_going_stepped_thread (struct thread_info
*tp
);
2065 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
2067 /* Are there any pending step-over requests? If so, run all we can
2068 now and return true. Otherwise, return false. */
2071 start_step_over (void)
2073 struct thread_info
*tp
, *next
;
2075 /* Don't start a new step-over if we already have an in-line
2076 step-over operation ongoing. */
2077 if (step_over_info_valid_p ())
2080 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
2082 struct execution_control_state ecss
;
2083 struct execution_control_state
*ecs
= &ecss
;
2084 step_over_what step_what
;
2085 int must_be_in_line
;
2087 gdb_assert (!tp
->stop_requested
);
2089 next
= thread_step_over_chain_next (tp
);
2091 /* If this inferior already has a displaced step in process,
2092 don't start a new one. */
2093 if (displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2096 step_what
= thread_still_needs_step_over (tp
);
2097 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
2098 || ((step_what
& STEP_OVER_BREAKPOINT
)
2099 && !use_displaced_stepping (tp
)));
2101 /* We currently stop all threads of all processes to step-over
2102 in-line. If we need to start a new in-line step-over, let
2103 any pending displaced steps finish first. */
2104 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
2107 thread_step_over_chain_remove (tp
);
2109 if (step_over_queue_head
== NULL
)
2112 fprintf_unfiltered (gdb_stdlog
,
2113 "infrun: step-over queue now empty\n");
2116 if (tp
->control
.trap_expected
2120 internal_error (__FILE__
, __LINE__
,
2121 "[%s] has inconsistent state: "
2122 "trap_expected=%d, resumed=%d, executing=%d\n",
2123 target_pid_to_str (tp
->ptid
),
2124 tp
->control
.trap_expected
,
2130 fprintf_unfiltered (gdb_stdlog
,
2131 "infrun: resuming [%s] for step-over\n",
2132 target_pid_to_str (tp
->ptid
));
2134 /* keep_going_pass_signal skips the step-over if the breakpoint
2135 is no longer inserted. In all-stop, we want to keep looking
2136 for a thread that needs a step-over instead of resuming TP,
2137 because we wouldn't be able to resume anything else until the
2138 target stops again. In non-stop, the resume always resumes
2139 only TP, so it's OK to let the thread resume freely. */
2140 if (!target_is_non_stop_p () && !step_what
)
2143 switch_to_thread (tp
->ptid
);
2144 reset_ecs (ecs
, tp
);
2145 keep_going_pass_signal (ecs
);
2147 if (!ecs
->wait_some_more
)
2148 error (_("Command aborted."));
2150 gdb_assert (tp
->resumed
);
2152 /* If we started a new in-line step-over, we're done. */
2153 if (step_over_info_valid_p ())
2155 gdb_assert (tp
->control
.trap_expected
);
2159 if (!target_is_non_stop_p ())
2161 /* On all-stop, shouldn't have resumed unless we needed a
2163 gdb_assert (tp
->control
.trap_expected
2164 || tp
->step_after_step_resume_breakpoint
);
2166 /* With remote targets (at least), in all-stop, we can't
2167 issue any further remote commands until the program stops
2172 /* Either the thread no longer needed a step-over, or a new
2173 displaced stepping sequence started. Even in the latter
2174 case, continue looking. Maybe we can also start another
2175 displaced step on a thread of other process. */
2181 /* Update global variables holding ptids to hold NEW_PTID if they were
2182 holding OLD_PTID. */
2184 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2186 struct displaced_step_inferior_state
*displaced
;
2188 if (ptid_equal (inferior_ptid
, old_ptid
))
2189 inferior_ptid
= new_ptid
;
2191 for (displaced
= displaced_step_inferior_states
;
2193 displaced
= displaced
->next
)
2195 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
2196 displaced
->step_ptid
= new_ptid
;
2203 /* Things to clean up if we QUIT out of resume (). */
2205 resume_cleanups (void *ignore
)
2207 if (!ptid_equal (inferior_ptid
, null_ptid
))
2208 delete_single_step_breakpoints (inferior_thread ());
2213 static const char schedlock_off
[] = "off";
2214 static const char schedlock_on
[] = "on";
2215 static const char schedlock_step
[] = "step";
2216 static const char schedlock_replay
[] = "replay";
2217 static const char *const scheduler_enums
[] = {
2224 static const char *scheduler_mode
= schedlock_replay
;
2226 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2227 struct cmd_list_element
*c
, const char *value
)
2229 fprintf_filtered (file
,
2230 _("Mode for locking scheduler "
2231 "during execution is \"%s\".\n"),
2236 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
2238 if (!target_can_lock_scheduler
)
2240 scheduler_mode
= schedlock_off
;
2241 error (_("Target '%s' cannot support this command."), target_shortname
);
2245 /* True if execution commands resume all threads of all processes by
2246 default; otherwise, resume only threads of the current inferior
2248 int sched_multi
= 0;
2250 /* Try to setup for software single stepping over the specified location.
2251 Return 1 if target_resume() should use hardware single step.
2253 GDBARCH the current gdbarch.
2254 PC the location to step over. */
2257 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2261 if (execution_direction
== EXEC_FORWARD
2262 && gdbarch_software_single_step_p (gdbarch
))
2263 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2271 user_visible_resume_ptid (int step
)
2277 /* With non-stop mode on, threads are always handled
2279 resume_ptid
= inferior_ptid
;
2281 else if ((scheduler_mode
== schedlock_on
)
2282 || (scheduler_mode
== schedlock_step
&& step
))
2284 /* User-settable 'scheduler' mode requires solo thread
2286 resume_ptid
= inferior_ptid
;
2288 else if ((scheduler_mode
== schedlock_replay
)
2289 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2291 /* User-settable 'scheduler' mode requires solo thread resume in replay
2293 resume_ptid
= inferior_ptid
;
2295 else if (!sched_multi
&& target_supports_multi_process ())
2297 /* Resume all threads of the current process (and none of other
2299 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2303 /* Resume all threads of all processes. */
2304 resume_ptid
= RESUME_ALL
;
2310 /* Return a ptid representing the set of threads that we will resume,
2311 in the perspective of the target, assuming run control handling
2312 does not require leaving some threads stopped (e.g., stepping past
2313 breakpoint). USER_STEP indicates whether we're about to start the
2314 target for a stepping command. */
2317 internal_resume_ptid (int user_step
)
2319 /* In non-stop, we always control threads individually. Note that
2320 the target may always work in non-stop mode even with "set
2321 non-stop off", in which case user_visible_resume_ptid could
2322 return a wildcard ptid. */
2323 if (target_is_non_stop_p ())
2324 return inferior_ptid
;
2326 return user_visible_resume_ptid (user_step
);
2329 /* Wrapper for target_resume, that handles infrun-specific
2333 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2335 struct thread_info
*tp
= inferior_thread ();
2337 gdb_assert (!tp
->stop_requested
);
2339 /* Install inferior's terminal modes. */
2340 target_terminal_inferior ();
2342 /* Avoid confusing the next resume, if the next stop/resume
2343 happens to apply to another thread. */
2344 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2346 /* Advise target which signals may be handled silently.
2348 If we have removed breakpoints because we are stepping over one
2349 in-line (in any thread), we need to receive all signals to avoid
2350 accidentally skipping a breakpoint during execution of a signal
2353 Likewise if we're displaced stepping, otherwise a trap for a
2354 breakpoint in a signal handler might be confused with the
2355 displaced step finishing. We don't make the displaced_step_fixup
2356 step distinguish the cases instead, because:
2358 - a backtrace while stopped in the signal handler would show the
2359 scratch pad as frame older than the signal handler, instead of
2360 the real mainline code.
2362 - when the thread is later resumed, the signal handler would
2363 return to the scratch pad area, which would no longer be
2365 if (step_over_info_valid_p ()
2366 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2367 target_pass_signals (0, NULL
);
2369 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2371 target_resume (resume_ptid
, step
, sig
);
2373 target_commit_resume ();
2376 /* Resume the inferior, but allow a QUIT. This is useful if the user
2377 wants to interrupt some lengthy single-stepping operation
2378 (for child processes, the SIGINT goes to the inferior, and so
2379 we get a SIGINT random_signal, but for remote debugging and perhaps
2380 other targets, that's not true).
2382 SIG is the signal to give the inferior (zero for none). */
2384 resume (enum gdb_signal sig
)
2386 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2387 struct regcache
*regcache
= get_current_regcache ();
2388 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2389 struct thread_info
*tp
= inferior_thread ();
2390 CORE_ADDR pc
= regcache_read_pc (regcache
);
2391 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2393 /* This represents the user's step vs continue request. When
2394 deciding whether "set scheduler-locking step" applies, it's the
2395 user's intention that counts. */
2396 const int user_step
= tp
->control
.stepping_command
;
2397 /* This represents what we'll actually request the target to do.
2398 This can decay from a step to a continue, if e.g., we need to
2399 implement single-stepping with breakpoints (software
2403 gdb_assert (!tp
->stop_requested
);
2404 gdb_assert (!thread_is_in_step_over_chain (tp
));
2408 if (tp
->suspend
.waitstatus_pending_p
)
2414 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2415 fprintf_unfiltered (gdb_stdlog
,
2416 "infrun: resume: thread %s has pending wait status %s "
2417 "(currently_stepping=%d).\n",
2418 target_pid_to_str (tp
->ptid
), statstr
,
2419 currently_stepping (tp
));
2425 /* FIXME: What should we do if we are supposed to resume this
2426 thread with a signal? Maybe we should maintain a queue of
2427 pending signals to deliver. */
2428 if (sig
!= GDB_SIGNAL_0
)
2430 warning (_("Couldn't deliver signal %s to %s."),
2431 gdb_signal_to_name (sig
), target_pid_to_str (tp
->ptid
));
2434 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2435 discard_cleanups (old_cleanups
);
2437 if (target_can_async_p ())
2442 tp
->stepped_breakpoint
= 0;
2444 /* Depends on stepped_breakpoint. */
2445 step
= currently_stepping (tp
);
2447 if (current_inferior ()->waiting_for_vfork_done
)
2449 /* Don't try to single-step a vfork parent that is waiting for
2450 the child to get out of the shared memory region (by exec'ing
2451 or exiting). This is particularly important on software
2452 single-step archs, as the child process would trip on the
2453 software single step breakpoint inserted for the parent
2454 process. Since the parent will not actually execute any
2455 instruction until the child is out of the shared region (such
2456 are vfork's semantics), it is safe to simply continue it.
2457 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2458 the parent, and tell it to `keep_going', which automatically
2459 re-sets it stepping. */
2461 fprintf_unfiltered (gdb_stdlog
,
2462 "infrun: resume : clear step\n");
2467 fprintf_unfiltered (gdb_stdlog
,
2468 "infrun: resume (step=%d, signal=%s), "
2469 "trap_expected=%d, current thread [%s] at %s\n",
2470 step
, gdb_signal_to_symbol_string (sig
),
2471 tp
->control
.trap_expected
,
2472 target_pid_to_str (inferior_ptid
),
2473 paddress (gdbarch
, pc
));
2475 /* Normally, by the time we reach `resume', the breakpoints are either
2476 removed or inserted, as appropriate. The exception is if we're sitting
2477 at a permanent breakpoint; we need to step over it, but permanent
2478 breakpoints can't be removed. So we have to test for it here. */
2479 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2481 if (sig
!= GDB_SIGNAL_0
)
2483 /* We have a signal to pass to the inferior. The resume
2484 may, or may not take us to the signal handler. If this
2485 is a step, we'll need to stop in the signal handler, if
2486 there's one, (if the target supports stepping into
2487 handlers), or in the next mainline instruction, if
2488 there's no handler. If this is a continue, we need to be
2489 sure to run the handler with all breakpoints inserted.
2490 In all cases, set a breakpoint at the current address
2491 (where the handler returns to), and once that breakpoint
2492 is hit, resume skipping the permanent breakpoint. If
2493 that breakpoint isn't hit, then we've stepped into the
2494 signal handler (or hit some other event). We'll delete
2495 the step-resume breakpoint then. */
2498 fprintf_unfiltered (gdb_stdlog
,
2499 "infrun: resume: skipping permanent breakpoint, "
2500 "deliver signal first\n");
2502 clear_step_over_info ();
2503 tp
->control
.trap_expected
= 0;
2505 if (tp
->control
.step_resume_breakpoint
== NULL
)
2507 /* Set a "high-priority" step-resume, as we don't want
2508 user breakpoints at PC to trigger (again) when this
2510 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2511 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2513 tp
->step_after_step_resume_breakpoint
= step
;
2516 insert_breakpoints ();
2520 /* There's no signal to pass, we can go ahead and skip the
2521 permanent breakpoint manually. */
2523 fprintf_unfiltered (gdb_stdlog
,
2524 "infrun: resume: skipping permanent breakpoint\n");
2525 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2526 /* Update pc to reflect the new address from which we will
2527 execute instructions. */
2528 pc
= regcache_read_pc (regcache
);
2532 /* We've already advanced the PC, so the stepping part
2533 is done. Now we need to arrange for a trap to be
2534 reported to handle_inferior_event. Set a breakpoint
2535 at the current PC, and run to it. Don't update
2536 prev_pc, because if we end in
2537 switch_back_to_stepped_thread, we want the "expected
2538 thread advanced also" branch to be taken. IOW, we
2539 don't want this thread to step further from PC
2541 gdb_assert (!step_over_info_valid_p ());
2542 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2543 insert_breakpoints ();
2545 resume_ptid
= internal_resume_ptid (user_step
);
2546 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2547 discard_cleanups (old_cleanups
);
2554 /* If we have a breakpoint to step over, make sure to do a single
2555 step only. Same if we have software watchpoints. */
2556 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2557 tp
->control
.may_range_step
= 0;
2559 /* If enabled, step over breakpoints by executing a copy of the
2560 instruction at a different address.
2562 We can't use displaced stepping when we have a signal to deliver;
2563 the comments for displaced_step_prepare explain why. The
2564 comments in the handle_inferior event for dealing with 'random
2565 signals' explain what we do instead.
2567 We can't use displaced stepping when we are waiting for vfork_done
2568 event, displaced stepping breaks the vfork child similarly as single
2569 step software breakpoint. */
2570 if (tp
->control
.trap_expected
2571 && use_displaced_stepping (tp
)
2572 && !step_over_info_valid_p ()
2573 && sig
== GDB_SIGNAL_0
2574 && !current_inferior ()->waiting_for_vfork_done
)
2576 int prepared
= displaced_step_prepare (inferior_ptid
);
2581 fprintf_unfiltered (gdb_stdlog
,
2582 "Got placed in step-over queue\n");
2584 tp
->control
.trap_expected
= 0;
2585 discard_cleanups (old_cleanups
);
2588 else if (prepared
< 0)
2590 /* Fallback to stepping over the breakpoint in-line. */
2592 if (target_is_non_stop_p ())
2593 stop_all_threads ();
2595 set_step_over_info (get_regcache_aspace (regcache
),
2596 regcache_read_pc (regcache
), 0, tp
->global_num
);
2598 step
= maybe_software_singlestep (gdbarch
, pc
);
2600 insert_breakpoints ();
2602 else if (prepared
> 0)
2604 struct displaced_step_inferior_state
*displaced
;
2606 /* Update pc to reflect the new address from which we will
2607 execute instructions due to displaced stepping. */
2608 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2610 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2611 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2612 displaced
->step_closure
);
2616 /* Do we need to do it the hard way, w/temp breakpoints? */
2618 step
= maybe_software_singlestep (gdbarch
, pc
);
2620 /* Currently, our software single-step implementation leads to different
2621 results than hardware single-stepping in one situation: when stepping
2622 into delivering a signal which has an associated signal handler,
2623 hardware single-step will stop at the first instruction of the handler,
2624 while software single-step will simply skip execution of the handler.
2626 For now, this difference in behavior is accepted since there is no
2627 easy way to actually implement single-stepping into a signal handler
2628 without kernel support.
2630 However, there is one scenario where this difference leads to follow-on
2631 problems: if we're stepping off a breakpoint by removing all breakpoints
2632 and then single-stepping. In this case, the software single-step
2633 behavior means that even if there is a *breakpoint* in the signal
2634 handler, GDB still would not stop.
2636 Fortunately, we can at least fix this particular issue. We detect
2637 here the case where we are about to deliver a signal while software
2638 single-stepping with breakpoints removed. In this situation, we
2639 revert the decisions to remove all breakpoints and insert single-
2640 step breakpoints, and instead we install a step-resume breakpoint
2641 at the current address, deliver the signal without stepping, and
2642 once we arrive back at the step-resume breakpoint, actually step
2643 over the breakpoint we originally wanted to step over. */
2644 if (thread_has_single_step_breakpoints_set (tp
)
2645 && sig
!= GDB_SIGNAL_0
2646 && step_over_info_valid_p ())
2648 /* If we have nested signals or a pending signal is delivered
2649 immediately after a handler returns, might might already have
2650 a step-resume breakpoint set on the earlier handler. We cannot
2651 set another step-resume breakpoint; just continue on until the
2652 original breakpoint is hit. */
2653 if (tp
->control
.step_resume_breakpoint
== NULL
)
2655 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2656 tp
->step_after_step_resume_breakpoint
= 1;
2659 delete_single_step_breakpoints (tp
);
2661 clear_step_over_info ();
2662 tp
->control
.trap_expected
= 0;
2664 insert_breakpoints ();
2667 /* If STEP is set, it's a request to use hardware stepping
2668 facilities. But in that case, we should never
2669 use singlestep breakpoint. */
2670 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2672 /* Decide the set of threads to ask the target to resume. */
2673 if (tp
->control
.trap_expected
)
2675 /* We're allowing a thread to run past a breakpoint it has
2676 hit, either by single-stepping the thread with the breakpoint
2677 removed, or by displaced stepping, with the breakpoint inserted.
2678 In the former case, we need to single-step only this thread,
2679 and keep others stopped, as they can miss this breakpoint if
2680 allowed to run. That's not really a problem for displaced
2681 stepping, but, we still keep other threads stopped, in case
2682 another thread is also stopped for a breakpoint waiting for
2683 its turn in the displaced stepping queue. */
2684 resume_ptid
= inferior_ptid
;
2687 resume_ptid
= internal_resume_ptid (user_step
);
2689 if (execution_direction
!= EXEC_REVERSE
2690 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2692 /* There are two cases where we currently need to step a
2693 breakpoint instruction when we have a signal to deliver:
2695 - See handle_signal_stop where we handle random signals that
2696 could take out us out of the stepping range. Normally, in
2697 that case we end up continuing (instead of stepping) over the
2698 signal handler with a breakpoint at PC, but there are cases
2699 where we should _always_ single-step, even if we have a
2700 step-resume breakpoint, like when a software watchpoint is
2701 set. Assuming single-stepping and delivering a signal at the
2702 same time would takes us to the signal handler, then we could
2703 have removed the breakpoint at PC to step over it. However,
2704 some hardware step targets (like e.g., Mac OS) can't step
2705 into signal handlers, and for those, we need to leave the
2706 breakpoint at PC inserted, as otherwise if the handler
2707 recurses and executes PC again, it'll miss the breakpoint.
2708 So we leave the breakpoint inserted anyway, but we need to
2709 record that we tried to step a breakpoint instruction, so
2710 that adjust_pc_after_break doesn't end up confused.
2712 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2713 in one thread after another thread that was stepping had been
2714 momentarily paused for a step-over. When we re-resume the
2715 stepping thread, it may be resumed from that address with a
2716 breakpoint that hasn't trapped yet. Seen with
2717 gdb.threads/non-stop-fair-events.exp, on targets that don't
2718 do displaced stepping. */
2721 fprintf_unfiltered (gdb_stdlog
,
2722 "infrun: resume: [%s] stepped breakpoint\n",
2723 target_pid_to_str (tp
->ptid
));
2725 tp
->stepped_breakpoint
= 1;
2727 /* Most targets can step a breakpoint instruction, thus
2728 executing it normally. But if this one cannot, just
2729 continue and we will hit it anyway. */
2730 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2735 && tp
->control
.trap_expected
2736 && use_displaced_stepping (tp
)
2737 && !step_over_info_valid_p ())
2739 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2740 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2741 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2744 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2745 paddress (resume_gdbarch
, actual_pc
));
2746 read_memory (actual_pc
, buf
, sizeof (buf
));
2747 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2750 if (tp
->control
.may_range_step
)
2752 /* If we're resuming a thread with the PC out of the step
2753 range, then we're doing some nested/finer run control
2754 operation, like stepping the thread out of the dynamic
2755 linker or the displaced stepping scratch pad. We
2756 shouldn't have allowed a range step then. */
2757 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2760 do_target_resume (resume_ptid
, step
, sig
);
2762 discard_cleanups (old_cleanups
);
2769 /* Counter that tracks number of user visible stops. This can be used
2770 to tell whether a command has proceeded the inferior past the
2771 current location. This allows e.g., inferior function calls in
2772 breakpoint commands to not interrupt the command list. When the
2773 call finishes successfully, the inferior is standing at the same
2774 breakpoint as if nothing happened (and so we don't call
2776 static ULONGEST current_stop_id
;
2783 return current_stop_id
;
2786 /* Called when we report a user visible stop. */
2794 /* Clear out all variables saying what to do when inferior is continued.
2795 First do this, then set the ones you want, then call `proceed'. */
2798 clear_proceed_status_thread (struct thread_info
*tp
)
2801 fprintf_unfiltered (gdb_stdlog
,
2802 "infrun: clear_proceed_status_thread (%s)\n",
2803 target_pid_to_str (tp
->ptid
));
2805 /* If we're starting a new sequence, then the previous finished
2806 single-step is no longer relevant. */
2807 if (tp
->suspend
.waitstatus_pending_p
)
2809 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2812 fprintf_unfiltered (gdb_stdlog
,
2813 "infrun: clear_proceed_status: pending "
2814 "event of %s was a finished step. "
2816 target_pid_to_str (tp
->ptid
));
2818 tp
->suspend
.waitstatus_pending_p
= 0;
2819 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2821 else if (debug_infrun
)
2825 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2826 fprintf_unfiltered (gdb_stdlog
,
2827 "infrun: clear_proceed_status_thread: thread %s "
2828 "has pending wait status %s "
2829 "(currently_stepping=%d).\n",
2830 target_pid_to_str (tp
->ptid
), statstr
,
2831 currently_stepping (tp
));
2836 /* If this signal should not be seen by program, give it zero.
2837 Used for debugging signals. */
2838 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2839 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2841 thread_fsm_delete (tp
->thread_fsm
);
2842 tp
->thread_fsm
= NULL
;
2844 tp
->control
.trap_expected
= 0;
2845 tp
->control
.step_range_start
= 0;
2846 tp
->control
.step_range_end
= 0;
2847 tp
->control
.may_range_step
= 0;
2848 tp
->control
.step_frame_id
= null_frame_id
;
2849 tp
->control
.step_stack_frame_id
= null_frame_id
;
2850 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2851 tp
->control
.step_start_function
= NULL
;
2852 tp
->stop_requested
= 0;
2854 tp
->control
.stop_step
= 0;
2856 tp
->control
.proceed_to_finish
= 0;
2858 tp
->control
.stepping_command
= 0;
2860 /* Discard any remaining commands or status from previous stop. */
2861 bpstat_clear (&tp
->control
.stop_bpstat
);
2865 clear_proceed_status (int step
)
2867 /* With scheduler-locking replay, stop replaying other threads if we're
2868 not replaying the user-visible resume ptid.
2870 This is a convenience feature to not require the user to explicitly
2871 stop replaying the other threads. We're assuming that the user's
2872 intent is to resume tracing the recorded process. */
2873 if (!non_stop
&& scheduler_mode
== schedlock_replay
2874 && target_record_is_replaying (minus_one_ptid
)
2875 && !target_record_will_replay (user_visible_resume_ptid (step
),
2876 execution_direction
))
2877 target_record_stop_replaying ();
2881 struct thread_info
*tp
;
2884 resume_ptid
= user_visible_resume_ptid (step
);
2886 /* In all-stop mode, delete the per-thread status of all threads
2887 we're about to resume, implicitly and explicitly. */
2888 ALL_NON_EXITED_THREADS (tp
)
2890 if (!ptid_match (tp
->ptid
, resume_ptid
))
2892 clear_proceed_status_thread (tp
);
2896 if (!ptid_equal (inferior_ptid
, null_ptid
))
2898 struct inferior
*inferior
;
2902 /* If in non-stop mode, only delete the per-thread status of
2903 the current thread. */
2904 clear_proceed_status_thread (inferior_thread ());
2907 inferior
= current_inferior ();
2908 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2911 observer_notify_about_to_proceed ();
2914 /* Returns true if TP is still stopped at a breakpoint that needs
2915 stepping-over in order to make progress. If the breakpoint is gone
2916 meanwhile, we can skip the whole step-over dance. */
2919 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2921 if (tp
->stepping_over_breakpoint
)
2923 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2925 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2926 regcache_read_pc (regcache
))
2927 == ordinary_breakpoint_here
)
2930 tp
->stepping_over_breakpoint
= 0;
2936 /* Check whether thread TP still needs to start a step-over in order
2937 to make progress when resumed. Returns an bitwise or of enum
2938 step_over_what bits, indicating what needs to be stepped over. */
2940 static step_over_what
2941 thread_still_needs_step_over (struct thread_info
*tp
)
2943 step_over_what what
= 0;
2945 if (thread_still_needs_step_over_bp (tp
))
2946 what
|= STEP_OVER_BREAKPOINT
;
2948 if (tp
->stepping_over_watchpoint
2949 && !target_have_steppable_watchpoint
)
2950 what
|= STEP_OVER_WATCHPOINT
;
2955 /* Returns true if scheduler locking applies. STEP indicates whether
2956 we're about to do a step/next-like command to a thread. */
2959 schedlock_applies (struct thread_info
*tp
)
2961 return (scheduler_mode
== schedlock_on
2962 || (scheduler_mode
== schedlock_step
2963 && tp
->control
.stepping_command
)
2964 || (scheduler_mode
== schedlock_replay
2965 && target_record_will_replay (minus_one_ptid
,
2966 execution_direction
)));
2969 /* Basic routine for continuing the program in various fashions.
2971 ADDR is the address to resume at, or -1 for resume where stopped.
2972 SIGGNAL is the signal to give it, or 0 for none,
2973 or -1 for act according to how it stopped.
2974 STEP is nonzero if should trap after one instruction.
2975 -1 means return after that and print nothing.
2976 You should probably set various step_... variables
2977 before calling here, if you are stepping.
2979 You should call clear_proceed_status before calling proceed. */
2982 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2984 struct regcache
*regcache
;
2985 struct gdbarch
*gdbarch
;
2986 struct thread_info
*tp
;
2988 struct address_space
*aspace
;
2990 struct execution_control_state ecss
;
2991 struct execution_control_state
*ecs
= &ecss
;
2992 struct cleanup
*old_chain
;
2993 struct cleanup
*defer_resume_cleanup
;
2996 /* If we're stopped at a fork/vfork, follow the branch set by the
2997 "set follow-fork-mode" command; otherwise, we'll just proceed
2998 resuming the current thread. */
2999 if (!follow_fork ())
3001 /* The target for some reason decided not to resume. */
3003 if (target_can_async_p ())
3004 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3008 /* We'll update this if & when we switch to a new thread. */
3009 previous_inferior_ptid
= inferior_ptid
;
3011 regcache
= get_current_regcache ();
3012 gdbarch
= get_regcache_arch (regcache
);
3013 aspace
= get_regcache_aspace (regcache
);
3014 pc
= regcache_read_pc (regcache
);
3015 tp
= inferior_thread ();
3017 /* Fill in with reasonable starting values. */
3018 init_thread_stepping_state (tp
);
3020 gdb_assert (!thread_is_in_step_over_chain (tp
));
3022 if (addr
== (CORE_ADDR
) -1)
3025 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3026 && execution_direction
!= EXEC_REVERSE
)
3027 /* There is a breakpoint at the address we will resume at,
3028 step one instruction before inserting breakpoints so that
3029 we do not stop right away (and report a second hit at this
3032 Note, we don't do this in reverse, because we won't
3033 actually be executing the breakpoint insn anyway.
3034 We'll be (un-)executing the previous instruction. */
3035 tp
->stepping_over_breakpoint
= 1;
3036 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3037 && gdbarch_single_step_through_delay (gdbarch
,
3038 get_current_frame ()))
3039 /* We stepped onto an instruction that needs to be stepped
3040 again before re-inserting the breakpoint, do so. */
3041 tp
->stepping_over_breakpoint
= 1;
3045 regcache_write_pc (regcache
, addr
);
3048 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3049 tp
->suspend
.stop_signal
= siggnal
;
3051 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
3053 /* If an exception is thrown from this point on, make sure to
3054 propagate GDB's knowledge of the executing state to the
3055 frontend/user running state. */
3056 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
3058 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3059 threads (e.g., we might need to set threads stepping over
3060 breakpoints first), from the user/frontend's point of view, all
3061 threads in RESUME_PTID are now running. Unless we're calling an
3062 inferior function, as in that case we pretend the inferior
3063 doesn't run at all. */
3064 if (!tp
->control
.in_infcall
)
3065 set_running (resume_ptid
, 1);
3068 fprintf_unfiltered (gdb_stdlog
,
3069 "infrun: proceed (addr=%s, signal=%s)\n",
3070 paddress (gdbarch
, addr
),
3071 gdb_signal_to_symbol_string (siggnal
));
3073 annotate_starting ();
3075 /* Make sure that output from GDB appears before output from the
3077 gdb_flush (gdb_stdout
);
3079 /* In a multi-threaded task we may select another thread and
3080 then continue or step.
3082 But if a thread that we're resuming had stopped at a breakpoint,
3083 it will immediately cause another breakpoint stop without any
3084 execution (i.e. it will report a breakpoint hit incorrectly). So
3085 we must step over it first.
3087 Look for threads other than the current (TP) that reported a
3088 breakpoint hit and haven't been resumed yet since. */
3090 /* If scheduler locking applies, we can avoid iterating over all
3092 if (!non_stop
&& !schedlock_applies (tp
))
3094 struct thread_info
*current
= tp
;
3096 ALL_NON_EXITED_THREADS (tp
)
3098 /* Ignore the current thread here. It's handled
3103 /* Ignore threads of processes we're not resuming. */
3104 if (!ptid_match (tp
->ptid
, resume_ptid
))
3107 if (!thread_still_needs_step_over (tp
))
3110 gdb_assert (!thread_is_in_step_over_chain (tp
));
3113 fprintf_unfiltered (gdb_stdlog
,
3114 "infrun: need to step-over [%s] first\n",
3115 target_pid_to_str (tp
->ptid
));
3117 thread_step_over_chain_enqueue (tp
);
3123 /* Enqueue the current thread last, so that we move all other
3124 threads over their breakpoints first. */
3125 if (tp
->stepping_over_breakpoint
)
3126 thread_step_over_chain_enqueue (tp
);
3128 /* If the thread isn't started, we'll still need to set its prev_pc,
3129 so that switch_back_to_stepped_thread knows the thread hasn't
3130 advanced. Must do this before resuming any thread, as in
3131 all-stop/remote, once we resume we can't send any other packet
3132 until the target stops again. */
3133 tp
->prev_pc
= regcache_read_pc (regcache
);
3135 defer_resume_cleanup
= make_cleanup_defer_target_commit_resume ();
3137 started
= start_step_over ();
3139 if (step_over_info_valid_p ())
3141 /* Either this thread started a new in-line step over, or some
3142 other thread was already doing one. In either case, don't
3143 resume anything else until the step-over is finished. */
3145 else if (started
&& !target_is_non_stop_p ())
3147 /* A new displaced stepping sequence was started. In all-stop,
3148 we can't talk to the target anymore until it next stops. */
3150 else if (!non_stop
&& target_is_non_stop_p ())
3152 /* In all-stop, but the target is always in non-stop mode.
3153 Start all other threads that are implicitly resumed too. */
3154 ALL_NON_EXITED_THREADS (tp
)
3156 /* Ignore threads of processes we're not resuming. */
3157 if (!ptid_match (tp
->ptid
, resume_ptid
))
3163 fprintf_unfiltered (gdb_stdlog
,
3164 "infrun: proceed: [%s] resumed\n",
3165 target_pid_to_str (tp
->ptid
));
3166 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3170 if (thread_is_in_step_over_chain (tp
))
3173 fprintf_unfiltered (gdb_stdlog
,
3174 "infrun: proceed: [%s] needs step-over\n",
3175 target_pid_to_str (tp
->ptid
));
3180 fprintf_unfiltered (gdb_stdlog
,
3181 "infrun: proceed: resuming %s\n",
3182 target_pid_to_str (tp
->ptid
));
3184 reset_ecs (ecs
, tp
);
3185 switch_to_thread (tp
->ptid
);
3186 keep_going_pass_signal (ecs
);
3187 if (!ecs
->wait_some_more
)
3188 error (_("Command aborted."));
3191 else if (!tp
->resumed
&& !thread_is_in_step_over_chain (tp
))
3193 /* The thread wasn't started, and isn't queued, run it now. */
3194 reset_ecs (ecs
, tp
);
3195 switch_to_thread (tp
->ptid
);
3196 keep_going_pass_signal (ecs
);
3197 if (!ecs
->wait_some_more
)
3198 error (_("Command aborted."));
3201 do_cleanups (defer_resume_cleanup
);
3202 target_commit_resume ();
3204 discard_cleanups (old_chain
);
3206 /* Tell the event loop to wait for it to stop. If the target
3207 supports asynchronous execution, it'll do this from within
3209 if (!target_can_async_p ())
3210 mark_async_event_handler (infrun_async_inferior_event_token
);
3214 /* Start remote-debugging of a machine over a serial link. */
3217 start_remote (int from_tty
)
3219 struct inferior
*inferior
;
3221 inferior
= current_inferior ();
3222 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3224 /* Always go on waiting for the target, regardless of the mode. */
3225 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3226 indicate to wait_for_inferior that a target should timeout if
3227 nothing is returned (instead of just blocking). Because of this,
3228 targets expecting an immediate response need to, internally, set
3229 things up so that the target_wait() is forced to eventually
3231 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3232 differentiate to its caller what the state of the target is after
3233 the initial open has been performed. Here we're assuming that
3234 the target has stopped. It should be possible to eventually have
3235 target_open() return to the caller an indication that the target
3236 is currently running and GDB state should be set to the same as
3237 for an async run. */
3238 wait_for_inferior ();
3240 /* Now that the inferior has stopped, do any bookkeeping like
3241 loading shared libraries. We want to do this before normal_stop,
3242 so that the displayed frame is up to date. */
3243 post_create_inferior (¤t_target
, from_tty
);
3248 /* Initialize static vars when a new inferior begins. */
3251 init_wait_for_inferior (void)
3253 /* These are meaningless until the first time through wait_for_inferior. */
3255 breakpoint_init_inferior (inf_starting
);
3257 clear_proceed_status (0);
3259 target_last_wait_ptid
= minus_one_ptid
;
3261 previous_inferior_ptid
= inferior_ptid
;
3263 /* Discard any skipped inlined frames. */
3264 clear_inline_frame_state (minus_one_ptid
);
3269 static void handle_inferior_event (struct execution_control_state
*ecs
);
3271 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3272 struct execution_control_state
*ecs
);
3273 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3274 struct execution_control_state
*ecs
);
3275 static void handle_signal_stop (struct execution_control_state
*ecs
);
3276 static void check_exception_resume (struct execution_control_state
*,
3277 struct frame_info
*);
3279 static void end_stepping_range (struct execution_control_state
*ecs
);
3280 static void stop_waiting (struct execution_control_state
*ecs
);
3281 static void keep_going (struct execution_control_state
*ecs
);
3282 static void process_event_stop_test (struct execution_control_state
*ecs
);
3283 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3285 /* This function is attached as a "thread_stop_requested" observer.
3286 Cleanup local state that assumed the PTID was to be resumed, and
3287 report the stop to the frontend. */
3290 infrun_thread_stop_requested (ptid_t ptid
)
3292 struct thread_info
*tp
;
3294 /* PTID was requested to stop. If the thread was already stopped,
3295 but the user/frontend doesn't know about that yet (e.g., the
3296 thread had been temporarily paused for some step-over), set up
3297 for reporting the stop now. */
3298 ALL_NON_EXITED_THREADS (tp
)
3299 if (ptid_match (tp
->ptid
, ptid
))
3301 if (tp
->state
!= THREAD_RUNNING
)
3306 /* Remove matching threads from the step-over queue, so
3307 start_step_over doesn't try to resume them
3309 if (thread_is_in_step_over_chain (tp
))
3310 thread_step_over_chain_remove (tp
);
3312 /* If the thread is stopped, but the user/frontend doesn't
3313 know about that yet, queue a pending event, as if the
3314 thread had just stopped now. Unless the thread already had
3316 if (!tp
->suspend
.waitstatus_pending_p
)
3318 tp
->suspend
.waitstatus_pending_p
= 1;
3319 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_STOPPED
;
3320 tp
->suspend
.waitstatus
.value
.sig
= GDB_SIGNAL_0
;
3323 /* Clear the inline-frame state, since we're re-processing the
3325 clear_inline_frame_state (tp
->ptid
);
3327 /* If this thread was paused because some other thread was
3328 doing an inline-step over, let that finish first. Once
3329 that happens, we'll restart all threads and consume pending
3330 stop events then. */
3331 if (step_over_info_valid_p ())
3334 /* Otherwise we can process the (new) pending event now. Set
3335 it so this pending event is considered by
3342 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3344 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3345 nullify_last_target_wait_ptid ();
3348 /* Delete the step resume, single-step and longjmp/exception resume
3349 breakpoints of TP. */
3352 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3354 delete_step_resume_breakpoint (tp
);
3355 delete_exception_resume_breakpoint (tp
);
3356 delete_single_step_breakpoints (tp
);
3359 /* If the target still has execution, call FUNC for each thread that
3360 just stopped. In all-stop, that's all the non-exited threads; in
3361 non-stop, that's the current thread, only. */
3363 typedef void (*for_each_just_stopped_thread_callback_func
)
3364 (struct thread_info
*tp
);
3367 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3369 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3372 if (target_is_non_stop_p ())
3374 /* If in non-stop mode, only the current thread stopped. */
3375 func (inferior_thread ());
3379 struct thread_info
*tp
;
3381 /* In all-stop mode, all threads have stopped. */
3382 ALL_NON_EXITED_THREADS (tp
)
3389 /* Delete the step resume and longjmp/exception resume breakpoints of
3390 the threads that just stopped. */
3393 delete_just_stopped_threads_infrun_breakpoints (void)
3395 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3398 /* Delete the single-step breakpoints of the threads that just
3402 delete_just_stopped_threads_single_step_breakpoints (void)
3404 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3407 /* A cleanup wrapper. */
3410 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3412 delete_just_stopped_threads_infrun_breakpoints ();
3418 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3419 const struct target_waitstatus
*ws
)
3421 char *status_string
= target_waitstatus_to_string (ws
);
3424 /* The text is split over several lines because it was getting too long.
3425 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3426 output as a unit; we want only one timestamp printed if debug_timestamp
3429 stb
.printf ("infrun: target_wait (%d.%ld.%ld",
3430 ptid_get_pid (waiton_ptid
),
3431 ptid_get_lwp (waiton_ptid
),
3432 ptid_get_tid (waiton_ptid
));
3433 if (ptid_get_pid (waiton_ptid
) != -1)
3434 stb
.printf (" [%s]", target_pid_to_str (waiton_ptid
));
3435 stb
.printf (", status) =\n");
3436 stb
.printf ("infrun: %d.%ld.%ld [%s],\n",
3437 ptid_get_pid (result_ptid
),
3438 ptid_get_lwp (result_ptid
),
3439 ptid_get_tid (result_ptid
),
3440 target_pid_to_str (result_ptid
));
3441 stb
.printf ("infrun: %s\n", status_string
);
3443 /* This uses %s in part to handle %'s in the text, but also to avoid
3444 a gcc error: the format attribute requires a string literal. */
3445 fprintf_unfiltered (gdb_stdlog
, "%s", stb
.c_str ());
3447 xfree (status_string
);
3450 /* Select a thread at random, out of those which are resumed and have
3453 static struct thread_info
*
3454 random_pending_event_thread (ptid_t waiton_ptid
)
3456 struct thread_info
*event_tp
;
3458 int random_selector
;
3460 /* First see how many events we have. Count only resumed threads
3461 that have an event pending. */
3462 ALL_NON_EXITED_THREADS (event_tp
)
3463 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3464 && event_tp
->resumed
3465 && event_tp
->suspend
.waitstatus_pending_p
)
3468 if (num_events
== 0)
3471 /* Now randomly pick a thread out of those that have had events. */
3472 random_selector
= (int)
3473 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3475 if (debug_infrun
&& num_events
> 1)
3476 fprintf_unfiltered (gdb_stdlog
,
3477 "infrun: Found %d events, selecting #%d\n",
3478 num_events
, random_selector
);
3480 /* Select the Nth thread that has had an event. */
3481 ALL_NON_EXITED_THREADS (event_tp
)
3482 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3483 && event_tp
->resumed
3484 && event_tp
->suspend
.waitstatus_pending_p
)
3485 if (random_selector
-- == 0)
3491 /* Wrapper for target_wait that first checks whether threads have
3492 pending statuses to report before actually asking the target for
3496 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3499 struct thread_info
*tp
;
3501 /* First check if there is a resumed thread with a wait status
3503 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
3505 tp
= random_pending_event_thread (ptid
);
3510 fprintf_unfiltered (gdb_stdlog
,
3511 "infrun: Waiting for specific thread %s.\n",
3512 target_pid_to_str (ptid
));
3514 /* We have a specific thread to check. */
3515 tp
= find_thread_ptid (ptid
);
3516 gdb_assert (tp
!= NULL
);
3517 if (!tp
->suspend
.waitstatus_pending_p
)
3522 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3523 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3525 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
3526 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3530 pc
= regcache_read_pc (regcache
);
3532 if (pc
!= tp
->suspend
.stop_pc
)
3535 fprintf_unfiltered (gdb_stdlog
,
3536 "infrun: PC of %s changed. was=%s, now=%s\n",
3537 target_pid_to_str (tp
->ptid
),
3538 paddress (gdbarch
, tp
->prev_pc
),
3539 paddress (gdbarch
, pc
));
3542 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3545 fprintf_unfiltered (gdb_stdlog
,
3546 "infrun: previous breakpoint of %s, at %s gone\n",
3547 target_pid_to_str (tp
->ptid
),
3548 paddress (gdbarch
, pc
));
3556 fprintf_unfiltered (gdb_stdlog
,
3557 "infrun: pending event of %s cancelled.\n",
3558 target_pid_to_str (tp
->ptid
));
3560 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3561 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3571 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3572 fprintf_unfiltered (gdb_stdlog
,
3573 "infrun: Using pending wait status %s for %s.\n",
3575 target_pid_to_str (tp
->ptid
));
3579 /* Now that we've selected our final event LWP, un-adjust its PC
3580 if it was a software breakpoint (and the target doesn't
3581 always adjust the PC itself). */
3582 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3583 && !target_supports_stopped_by_sw_breakpoint ())
3585 struct regcache
*regcache
;
3586 struct gdbarch
*gdbarch
;
3589 regcache
= get_thread_regcache (tp
->ptid
);
3590 gdbarch
= get_regcache_arch (regcache
);
3592 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3597 pc
= regcache_read_pc (regcache
);
3598 regcache_write_pc (regcache
, pc
+ decr_pc
);
3602 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3603 *status
= tp
->suspend
.waitstatus
;
3604 tp
->suspend
.waitstatus_pending_p
= 0;
3606 /* Wake up the event loop again, until all pending events are
3608 if (target_is_async_p ())
3609 mark_async_event_handler (infrun_async_inferior_event_token
);
3613 /* But if we don't find one, we'll have to wait. */
3615 if (deprecated_target_wait_hook
)
3616 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3618 event_ptid
= target_wait (ptid
, status
, options
);
3623 /* Prepare and stabilize the inferior for detaching it. E.g.,
3624 detaching while a thread is displaced stepping is a recipe for
3625 crashing it, as nothing would readjust the PC out of the scratch
3629 prepare_for_detach (void)
3631 struct inferior
*inf
= current_inferior ();
3632 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3633 struct cleanup
*old_chain_1
;
3634 struct displaced_step_inferior_state
*displaced
;
3636 displaced
= get_displaced_stepping_state (inf
->pid
);
3638 /* Is any thread of this process displaced stepping? If not,
3639 there's nothing else to do. */
3640 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3644 fprintf_unfiltered (gdb_stdlog
,
3645 "displaced-stepping in-process while detaching");
3647 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3650 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3652 struct cleanup
*old_chain_2
;
3653 struct execution_control_state ecss
;
3654 struct execution_control_state
*ecs
;
3657 memset (ecs
, 0, sizeof (*ecs
));
3659 overlay_cache_invalid
= 1;
3660 /* Flush target cache before starting to handle each event.
3661 Target was running and cache could be stale. This is just a
3662 heuristic. Running threads may modify target memory, but we
3663 don't get any event. */
3664 target_dcache_invalidate ();
3666 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3669 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3671 /* If an error happens while handling the event, propagate GDB's
3672 knowledge of the executing state to the frontend/user running
3674 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3677 /* Now figure out what to do with the result of the result. */
3678 handle_inferior_event (ecs
);
3680 /* No error, don't finish the state yet. */
3681 discard_cleanups (old_chain_2
);
3683 /* Breakpoints and watchpoints are not installed on the target
3684 at this point, and signals are passed directly to the
3685 inferior, so this must mean the process is gone. */
3686 if (!ecs
->wait_some_more
)
3688 discard_cleanups (old_chain_1
);
3689 error (_("Program exited while detaching"));
3693 discard_cleanups (old_chain_1
);
3696 /* Wait for control to return from inferior to debugger.
3698 If inferior gets a signal, we may decide to start it up again
3699 instead of returning. That is why there is a loop in this function.
3700 When this function actually returns it means the inferior
3701 should be left stopped and GDB should read more commands. */
3704 wait_for_inferior (void)
3706 struct cleanup
*old_cleanups
;
3707 struct cleanup
*thread_state_chain
;
3711 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3714 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3717 /* If an error happens while handling the event, propagate GDB's
3718 knowledge of the executing state to the frontend/user running
3720 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3724 struct execution_control_state ecss
;
3725 struct execution_control_state
*ecs
= &ecss
;
3726 ptid_t waiton_ptid
= minus_one_ptid
;
3728 memset (ecs
, 0, sizeof (*ecs
));
3730 overlay_cache_invalid
= 1;
3732 /* Flush target cache before starting to handle each event.
3733 Target was running and cache could be stale. This is just a
3734 heuristic. Running threads may modify target memory, but we
3735 don't get any event. */
3736 target_dcache_invalidate ();
3738 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3741 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3743 /* Now figure out what to do with the result of the result. */
3744 handle_inferior_event (ecs
);
3746 if (!ecs
->wait_some_more
)
3750 /* No error, don't finish the state yet. */
3751 discard_cleanups (thread_state_chain
);
3753 do_cleanups (old_cleanups
);
3756 /* Cleanup that reinstalls the readline callback handler, if the
3757 target is running in the background. If while handling the target
3758 event something triggered a secondary prompt, like e.g., a
3759 pagination prompt, we'll have removed the callback handler (see
3760 gdb_readline_wrapper_line). Need to do this as we go back to the
3761 event loop, ready to process further input. Note this has no
3762 effect if the handler hasn't actually been removed, because calling
3763 rl_callback_handler_install resets the line buffer, thus losing
3767 reinstall_readline_callback_handler_cleanup (void *arg
)
3769 struct ui
*ui
= current_ui
;
3773 /* We're not going back to the top level event loop yet. Don't
3774 install the readline callback, as it'd prep the terminal,
3775 readline-style (raw, noecho) (e.g., --batch). We'll install
3776 it the next time the prompt is displayed, when we're ready
3781 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3782 gdb_rl_callback_handler_reinstall ();
3785 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3786 that's just the event thread. In all-stop, that's all threads. */
3789 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3791 struct thread_info
*thr
= ecs
->event_thread
;
3793 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3794 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3798 ALL_NON_EXITED_THREADS (thr
)
3800 if (thr
->thread_fsm
== NULL
)
3802 if (thr
== ecs
->event_thread
)
3805 switch_to_thread (thr
->ptid
);
3806 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3809 if (ecs
->event_thread
!= NULL
)
3810 switch_to_thread (ecs
->event_thread
->ptid
);
3814 /* Helper for all_uis_check_sync_execution_done that works on the
3818 check_curr_ui_sync_execution_done (void)
3820 struct ui
*ui
= current_ui
;
3822 if (ui
->prompt_state
== PROMPT_NEEDED
3824 && !gdb_in_secondary_prompt_p (ui
))
3826 target_terminal_ours ();
3827 observer_notify_sync_execution_done ();
3828 ui_register_input_event_handler (ui
);
3835 all_uis_check_sync_execution_done (void)
3837 SWITCH_THRU_ALL_UIS ()
3839 check_curr_ui_sync_execution_done ();
3846 all_uis_on_sync_execution_starting (void)
3848 SWITCH_THRU_ALL_UIS ()
3850 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3851 async_disable_stdin ();
3855 /* Asynchronous version of wait_for_inferior. It is called by the
3856 event loop whenever a change of state is detected on the file
3857 descriptor corresponding to the target. It can be called more than
3858 once to complete a single execution command. In such cases we need
3859 to keep the state in a global variable ECSS. If it is the last time
3860 that this function is called for a single execution command, then
3861 report to the user that the inferior has stopped, and do the
3862 necessary cleanups. */
3865 fetch_inferior_event (void *client_data
)
3867 struct execution_control_state ecss
;
3868 struct execution_control_state
*ecs
= &ecss
;
3869 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3870 struct cleanup
*ts_old_chain
;
3872 ptid_t waiton_ptid
= minus_one_ptid
;
3874 memset (ecs
, 0, sizeof (*ecs
));
3876 /* Events are always processed with the main UI as current UI. This
3877 way, warnings, debug output, etc. are always consistently sent to
3878 the main console. */
3879 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3881 /* End up with readline processing input, if necessary. */
3882 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3884 /* We're handling a live event, so make sure we're doing live
3885 debugging. If we're looking at traceframes while the target is
3886 running, we're going to need to get back to that mode after
3887 handling the event. */
3890 make_cleanup_restore_current_traceframe ();
3891 set_current_traceframe (-1);
3895 /* In non-stop mode, the user/frontend should not notice a thread
3896 switch due to internal events. Make sure we reverse to the
3897 user selected thread and frame after handling the event and
3898 running any breakpoint commands. */
3899 make_cleanup_restore_current_thread ();
3901 overlay_cache_invalid
= 1;
3902 /* Flush target cache before starting to handle each event. Target
3903 was running and cache could be stale. This is just a heuristic.
3904 Running threads may modify target memory, but we don't get any
3906 target_dcache_invalidate ();
3908 scoped_restore save_exec_dir
3909 = make_scoped_restore (&execution_direction
, target_execution_direction ());
3911 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3912 target_can_async_p () ? TARGET_WNOHANG
: 0);
3915 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3917 /* If an error happens while handling the event, propagate GDB's
3918 knowledge of the executing state to the frontend/user running
3920 if (!target_is_non_stop_p ())
3921 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3923 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3925 /* Get executed before make_cleanup_restore_current_thread above to apply
3926 still for the thread which has thrown the exception. */
3927 make_bpstat_clear_actions_cleanup ();
3929 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3931 /* Now figure out what to do with the result of the result. */
3932 handle_inferior_event (ecs
);
3934 if (!ecs
->wait_some_more
)
3936 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3937 int should_stop
= 1;
3938 struct thread_info
*thr
= ecs
->event_thread
;
3939 int should_notify_stop
= 1;
3941 delete_just_stopped_threads_infrun_breakpoints ();
3945 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3947 if (thread_fsm
!= NULL
)
3948 should_stop
= thread_fsm_should_stop (thread_fsm
, thr
);
3957 clean_up_just_stopped_threads_fsms (ecs
);
3959 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3962 = thread_fsm_should_notify_stop (thr
->thread_fsm
);
3965 if (should_notify_stop
)
3969 /* We may not find an inferior if this was a process exit. */
3970 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3971 proceeded
= normal_stop ();
3975 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3982 /* No error, don't finish the thread states yet. */
3983 discard_cleanups (ts_old_chain
);
3985 /* Revert thread and frame. */
3986 do_cleanups (old_chain
);
3988 /* If a UI was in sync execution mode, and now isn't, restore its
3989 prompt (a synchronous execution command has finished, and we're
3990 ready for input). */
3991 all_uis_check_sync_execution_done ();
3994 && exec_done_display_p
3995 && (ptid_equal (inferior_ptid
, null_ptid
)
3996 || !is_running (inferior_ptid
)))
3997 printf_unfiltered (_("completed.\n"));
4000 /* Record the frame and location we're currently stepping through. */
4002 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
4004 struct thread_info
*tp
= inferior_thread ();
4006 tp
->control
.step_frame_id
= get_frame_id (frame
);
4007 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4009 tp
->current_symtab
= sal
.symtab
;
4010 tp
->current_line
= sal
.line
;
4013 /* Clear context switchable stepping state. */
4016 init_thread_stepping_state (struct thread_info
*tss
)
4018 tss
->stepped_breakpoint
= 0;
4019 tss
->stepping_over_breakpoint
= 0;
4020 tss
->stepping_over_watchpoint
= 0;
4021 tss
->step_after_step_resume_breakpoint
= 0;
4024 /* Set the cached copy of the last ptid/waitstatus. */
4027 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
4029 target_last_wait_ptid
= ptid
;
4030 target_last_waitstatus
= status
;
4033 /* Return the cached copy of the last pid/waitstatus returned by
4034 target_wait()/deprecated_target_wait_hook(). The data is actually
4035 cached by handle_inferior_event(), which gets called immediately
4036 after target_wait()/deprecated_target_wait_hook(). */
4039 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
4041 *ptidp
= target_last_wait_ptid
;
4042 *status
= target_last_waitstatus
;
4046 nullify_last_target_wait_ptid (void)
4048 target_last_wait_ptid
= minus_one_ptid
;
4051 /* Switch thread contexts. */
4054 context_switch (ptid_t ptid
)
4056 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
4058 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
4059 target_pid_to_str (inferior_ptid
));
4060 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
4061 target_pid_to_str (ptid
));
4064 switch_to_thread (ptid
);
4067 /* If the target can't tell whether we've hit breakpoints
4068 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4069 check whether that could have been caused by a breakpoint. If so,
4070 adjust the PC, per gdbarch_decr_pc_after_break. */
4073 adjust_pc_after_break (struct thread_info
*thread
,
4074 struct target_waitstatus
*ws
)
4076 struct regcache
*regcache
;
4077 struct gdbarch
*gdbarch
;
4078 struct address_space
*aspace
;
4079 CORE_ADDR breakpoint_pc
, decr_pc
;
4081 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4082 we aren't, just return.
4084 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4085 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4086 implemented by software breakpoints should be handled through the normal
4089 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4090 different signals (SIGILL or SIGEMT for instance), but it is less
4091 clear where the PC is pointing afterwards. It may not match
4092 gdbarch_decr_pc_after_break. I don't know any specific target that
4093 generates these signals at breakpoints (the code has been in GDB since at
4094 least 1992) so I can not guess how to handle them here.
4096 In earlier versions of GDB, a target with
4097 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4098 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4099 target with both of these set in GDB history, and it seems unlikely to be
4100 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4102 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4105 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4108 /* In reverse execution, when a breakpoint is hit, the instruction
4109 under it has already been de-executed. The reported PC always
4110 points at the breakpoint address, so adjusting it further would
4111 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4114 B1 0x08000000 : INSN1
4115 B2 0x08000001 : INSN2
4117 PC -> 0x08000003 : INSN4
4119 Say you're stopped at 0x08000003 as above. Reverse continuing
4120 from that point should hit B2 as below. Reading the PC when the
4121 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4122 been de-executed already.
4124 B1 0x08000000 : INSN1
4125 B2 PC -> 0x08000001 : INSN2
4129 We can't apply the same logic as for forward execution, because
4130 we would wrongly adjust the PC to 0x08000000, since there's a
4131 breakpoint at PC - 1. We'd then report a hit on B1, although
4132 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4134 if (execution_direction
== EXEC_REVERSE
)
4137 /* If the target can tell whether the thread hit a SW breakpoint,
4138 trust it. Targets that can tell also adjust the PC
4140 if (target_supports_stopped_by_sw_breakpoint ())
4143 /* Note that relying on whether a breakpoint is planted in memory to
4144 determine this can fail. E.g,. the breakpoint could have been
4145 removed since. Or the thread could have been told to step an
4146 instruction the size of a breakpoint instruction, and only
4147 _after_ was a breakpoint inserted at its address. */
4149 /* If this target does not decrement the PC after breakpoints, then
4150 we have nothing to do. */
4151 regcache
= get_thread_regcache (thread
->ptid
);
4152 gdbarch
= get_regcache_arch (regcache
);
4154 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4158 aspace
= get_regcache_aspace (regcache
);
4160 /* Find the location where (if we've hit a breakpoint) the
4161 breakpoint would be. */
4162 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4164 /* If the target can't tell whether a software breakpoint triggered,
4165 fallback to figuring it out based on breakpoints we think were
4166 inserted in the target, and on whether the thread was stepped or
4169 /* Check whether there actually is a software breakpoint inserted at
4172 If in non-stop mode, a race condition is possible where we've
4173 removed a breakpoint, but stop events for that breakpoint were
4174 already queued and arrive later. To suppress those spurious
4175 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4176 and retire them after a number of stop events are reported. Note
4177 this is an heuristic and can thus get confused. The real fix is
4178 to get the "stopped by SW BP and needs adjustment" info out of
4179 the target/kernel (and thus never reach here; see above). */
4180 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4181 || (target_is_non_stop_p ()
4182 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4184 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4186 if (record_full_is_used ())
4187 record_full_gdb_operation_disable_set ();
4189 /* When using hardware single-step, a SIGTRAP is reported for both
4190 a completed single-step and a software breakpoint. Need to
4191 differentiate between the two, as the latter needs adjusting
4192 but the former does not.
4194 The SIGTRAP can be due to a completed hardware single-step only if
4195 - we didn't insert software single-step breakpoints
4196 - this thread is currently being stepped
4198 If any of these events did not occur, we must have stopped due
4199 to hitting a software breakpoint, and have to back up to the
4202 As a special case, we could have hardware single-stepped a
4203 software breakpoint. In this case (prev_pc == breakpoint_pc),
4204 we also need to back up to the breakpoint address. */
4206 if (thread_has_single_step_breakpoints_set (thread
)
4207 || !currently_stepping (thread
)
4208 || (thread
->stepped_breakpoint
4209 && thread
->prev_pc
== breakpoint_pc
))
4210 regcache_write_pc (regcache
, breakpoint_pc
);
4212 do_cleanups (old_cleanups
);
4217 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4219 for (frame
= get_prev_frame (frame
);
4221 frame
= get_prev_frame (frame
))
4223 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4225 if (get_frame_type (frame
) != INLINE_FRAME
)
4232 /* If the event thread has the stop requested flag set, pretend it
4233 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4237 handle_stop_requested (struct execution_control_state
*ecs
)
4239 if (ecs
->event_thread
->stop_requested
)
4241 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4242 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4243 handle_signal_stop (ecs
);
4249 /* Auxiliary function that handles syscall entry/return events.
4250 It returns 1 if the inferior should keep going (and GDB
4251 should ignore the event), or 0 if the event deserves to be
4255 handle_syscall_event (struct execution_control_state
*ecs
)
4257 struct regcache
*regcache
;
4260 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4261 context_switch (ecs
->ptid
);
4263 regcache
= get_thread_regcache (ecs
->ptid
);
4264 syscall_number
= ecs
->ws
.value
.syscall_number
;
4265 stop_pc
= regcache_read_pc (regcache
);
4267 if (catch_syscall_enabled () > 0
4268 && catching_syscall_number (syscall_number
) > 0)
4271 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4274 ecs
->event_thread
->control
.stop_bpstat
4275 = bpstat_stop_status (get_regcache_aspace (regcache
),
4276 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4278 if (handle_stop_requested (ecs
))
4281 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4283 /* Catchpoint hit. */
4288 if (handle_stop_requested (ecs
))
4291 /* If no catchpoint triggered for this, then keep going. */
4296 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4299 fill_in_stop_func (struct gdbarch
*gdbarch
,
4300 struct execution_control_state
*ecs
)
4302 if (!ecs
->stop_func_filled_in
)
4304 /* Don't care about return value; stop_func_start and stop_func_name
4305 will both be 0 if it doesn't work. */
4306 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4307 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4308 ecs
->stop_func_start
4309 += gdbarch_deprecated_function_start_offset (gdbarch
);
4311 if (gdbarch_skip_entrypoint_p (gdbarch
))
4312 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4313 ecs
->stop_func_start
);
4315 ecs
->stop_func_filled_in
= 1;
4320 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4322 static enum stop_kind
4323 get_inferior_stop_soon (ptid_t ptid
)
4325 struct inferior
*inf
= find_inferior_ptid (ptid
);
4327 gdb_assert (inf
!= NULL
);
4328 return inf
->control
.stop_soon
;
4331 /* Wait for one event. Store the resulting waitstatus in WS, and
4332 return the event ptid. */
4335 wait_one (struct target_waitstatus
*ws
)
4338 ptid_t wait_ptid
= minus_one_ptid
;
4340 overlay_cache_invalid
= 1;
4342 /* Flush target cache before starting to handle each event.
4343 Target was running and cache could be stale. This is just a
4344 heuristic. Running threads may modify target memory, but we
4345 don't get any event. */
4346 target_dcache_invalidate ();
4348 if (deprecated_target_wait_hook
)
4349 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4351 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4354 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4359 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4360 instead of the current thread. */
4361 #define THREAD_STOPPED_BY(REASON) \
4363 thread_stopped_by_ ## REASON (ptid_t ptid) \
4365 struct cleanup *old_chain; \
4368 old_chain = save_inferior_ptid (); \
4369 inferior_ptid = ptid; \
4371 res = target_stopped_by_ ## REASON (); \
4373 do_cleanups (old_chain); \
4378 /* Generate thread_stopped_by_watchpoint. */
4379 THREAD_STOPPED_BY (watchpoint
)
4380 /* Generate thread_stopped_by_sw_breakpoint. */
4381 THREAD_STOPPED_BY (sw_breakpoint
)
4382 /* Generate thread_stopped_by_hw_breakpoint. */
4383 THREAD_STOPPED_BY (hw_breakpoint
)
4385 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4388 switch_to_thread_cleanup (void *ptid_p
)
4390 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4392 switch_to_thread (ptid
);
4395 /* Save the thread's event and stop reason to process it later. */
4398 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4400 struct regcache
*regcache
;
4401 struct address_space
*aspace
;
4407 statstr
= target_waitstatus_to_string (ws
);
4408 fprintf_unfiltered (gdb_stdlog
,
4409 "infrun: saving status %s for %d.%ld.%ld\n",
4411 ptid_get_pid (tp
->ptid
),
4412 ptid_get_lwp (tp
->ptid
),
4413 ptid_get_tid (tp
->ptid
));
4417 /* Record for later. */
4418 tp
->suspend
.waitstatus
= *ws
;
4419 tp
->suspend
.waitstatus_pending_p
= 1;
4421 regcache
= get_thread_regcache (tp
->ptid
);
4422 aspace
= get_regcache_aspace (regcache
);
4424 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4425 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4427 CORE_ADDR pc
= regcache_read_pc (regcache
);
4429 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4431 if (thread_stopped_by_watchpoint (tp
->ptid
))
4433 tp
->suspend
.stop_reason
4434 = TARGET_STOPPED_BY_WATCHPOINT
;
4436 else if (target_supports_stopped_by_sw_breakpoint ()
4437 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4439 tp
->suspend
.stop_reason
4440 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4442 else if (target_supports_stopped_by_hw_breakpoint ()
4443 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4445 tp
->suspend
.stop_reason
4446 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4448 else if (!target_supports_stopped_by_hw_breakpoint ()
4449 && hardware_breakpoint_inserted_here_p (aspace
,
4452 tp
->suspend
.stop_reason
4453 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4455 else if (!target_supports_stopped_by_sw_breakpoint ()
4456 && software_breakpoint_inserted_here_p (aspace
,
4459 tp
->suspend
.stop_reason
4460 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4462 else if (!thread_has_single_step_breakpoints_set (tp
)
4463 && currently_stepping (tp
))
4465 tp
->suspend
.stop_reason
4466 = TARGET_STOPPED_BY_SINGLE_STEP
;
4471 /* A cleanup that disables thread create/exit events. */
4474 disable_thread_events (void *arg
)
4476 target_thread_events (0);
4482 stop_all_threads (void)
4484 /* We may need multiple passes to discover all threads. */
4488 struct cleanup
*old_chain
;
4490 gdb_assert (target_is_non_stop_p ());
4493 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4495 entry_ptid
= inferior_ptid
;
4496 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4498 target_thread_events (1);
4499 make_cleanup (disable_thread_events
, NULL
);
4501 /* Request threads to stop, and then wait for the stops. Because
4502 threads we already know about can spawn more threads while we're
4503 trying to stop them, and we only learn about new threads when we
4504 update the thread list, do this in a loop, and keep iterating
4505 until two passes find no threads that need to be stopped. */
4506 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4509 fprintf_unfiltered (gdb_stdlog
,
4510 "infrun: stop_all_threads, pass=%d, "
4511 "iterations=%d\n", pass
, iterations
);
4515 struct target_waitstatus ws
;
4517 struct thread_info
*t
;
4519 update_thread_list ();
4521 /* Go through all threads looking for threads that we need
4522 to tell the target to stop. */
4523 ALL_NON_EXITED_THREADS (t
)
4527 /* If already stopping, don't request a stop again.
4528 We just haven't seen the notification yet. */
4529 if (!t
->stop_requested
)
4532 fprintf_unfiltered (gdb_stdlog
,
4533 "infrun: %s executing, "
4535 target_pid_to_str (t
->ptid
));
4536 target_stop (t
->ptid
);
4537 t
->stop_requested
= 1;
4542 fprintf_unfiltered (gdb_stdlog
,
4543 "infrun: %s executing, "
4544 "already stopping\n",
4545 target_pid_to_str (t
->ptid
));
4548 if (t
->stop_requested
)
4554 fprintf_unfiltered (gdb_stdlog
,
4555 "infrun: %s not executing\n",
4556 target_pid_to_str (t
->ptid
));
4558 /* The thread may be not executing, but still be
4559 resumed with a pending status to process. */
4567 /* If we find new threads on the second iteration, restart
4568 over. We want to see two iterations in a row with all
4573 event_ptid
= wait_one (&ws
);
4574 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4576 /* All resumed threads exited. */
4578 else if (ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4579 || ws
.kind
== TARGET_WAITKIND_EXITED
4580 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4584 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4586 fprintf_unfiltered (gdb_stdlog
,
4587 "infrun: %s exited while "
4588 "stopping threads\n",
4589 target_pid_to_str (ptid
));
4594 struct inferior
*inf
;
4596 t
= find_thread_ptid (event_ptid
);
4598 t
= add_thread (event_ptid
);
4600 t
->stop_requested
= 0;
4603 t
->control
.may_range_step
= 0;
4605 /* This may be the first time we see the inferior report
4607 inf
= find_inferior_ptid (event_ptid
);
4608 if (inf
->needs_setup
)
4610 switch_to_thread_no_regs (t
);
4614 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4615 && ws
.value
.sig
== GDB_SIGNAL_0
)
4617 /* We caught the event that we intended to catch, so
4618 there's no event pending. */
4619 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4620 t
->suspend
.waitstatus_pending_p
= 0;
4622 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4624 /* Add it back to the step-over queue. */
4627 fprintf_unfiltered (gdb_stdlog
,
4628 "infrun: displaced-step of %s "
4629 "canceled: adding back to the "
4630 "step-over queue\n",
4631 target_pid_to_str (t
->ptid
));
4633 t
->control
.trap_expected
= 0;
4634 thread_step_over_chain_enqueue (t
);
4639 enum gdb_signal sig
;
4640 struct regcache
*regcache
;
4646 statstr
= target_waitstatus_to_string (&ws
);
4647 fprintf_unfiltered (gdb_stdlog
,
4648 "infrun: target_wait %s, saving "
4649 "status for %d.%ld.%ld\n",
4651 ptid_get_pid (t
->ptid
),
4652 ptid_get_lwp (t
->ptid
),
4653 ptid_get_tid (t
->ptid
));
4657 /* Record for later. */
4658 save_waitstatus (t
, &ws
);
4660 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4661 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4663 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4665 /* Add it back to the step-over queue. */
4666 t
->control
.trap_expected
= 0;
4667 thread_step_over_chain_enqueue (t
);
4670 regcache
= get_thread_regcache (t
->ptid
);
4671 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4675 fprintf_unfiltered (gdb_stdlog
,
4676 "infrun: saved stop_pc=%s for %s "
4677 "(currently_stepping=%d)\n",
4678 paddress (target_gdbarch (),
4679 t
->suspend
.stop_pc
),
4680 target_pid_to_str (t
->ptid
),
4681 currently_stepping (t
));
4688 do_cleanups (old_chain
);
4691 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4694 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4697 handle_no_resumed (struct execution_control_state
*ecs
)
4699 struct inferior
*inf
;
4700 struct thread_info
*thread
;
4702 if (target_can_async_p ())
4709 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4717 /* There were no unwaited-for children left in the target, but,
4718 we're not synchronously waiting for events either. Just
4722 fprintf_unfiltered (gdb_stdlog
,
4723 "infrun: TARGET_WAITKIND_NO_RESUMED "
4724 "(ignoring: bg)\n");
4725 prepare_to_wait (ecs
);
4730 /* Otherwise, if we were running a synchronous execution command, we
4731 may need to cancel it and give the user back the terminal.
4733 In non-stop mode, the target can't tell whether we've already
4734 consumed previous stop events, so it can end up sending us a
4735 no-resumed event like so:
4737 #0 - thread 1 is left stopped
4739 #1 - thread 2 is resumed and hits breakpoint
4740 -> TARGET_WAITKIND_STOPPED
4742 #2 - thread 3 is resumed and exits
4743 this is the last resumed thread, so
4744 -> TARGET_WAITKIND_NO_RESUMED
4746 #3 - gdb processes stop for thread 2 and decides to re-resume
4749 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4750 thread 2 is now resumed, so the event should be ignored.
4752 IOW, if the stop for thread 2 doesn't end a foreground command,
4753 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4754 event. But it could be that the event meant that thread 2 itself
4755 (or whatever other thread was the last resumed thread) exited.
4757 To address this we refresh the thread list and check whether we
4758 have resumed threads _now_. In the example above, this removes
4759 thread 3 from the thread list. If thread 2 was re-resumed, we
4760 ignore this event. If we find no thread resumed, then we cancel
4761 the synchronous command show "no unwaited-for " to the user. */
4762 update_thread_list ();
4764 ALL_NON_EXITED_THREADS (thread
)
4766 if (thread
->executing
4767 || thread
->suspend
.waitstatus_pending_p
)
4769 /* There were no unwaited-for children left in the target at
4770 some point, but there are now. Just ignore. */
4772 fprintf_unfiltered (gdb_stdlog
,
4773 "infrun: TARGET_WAITKIND_NO_RESUMED "
4774 "(ignoring: found resumed)\n");
4775 prepare_to_wait (ecs
);
4780 /* Note however that we may find no resumed thread because the whole
4781 process exited meanwhile (thus updating the thread list results
4782 in an empty thread list). In this case we know we'll be getting
4783 a process exit event shortly. */
4789 thread
= any_live_thread_of_process (inf
->pid
);
4793 fprintf_unfiltered (gdb_stdlog
,
4794 "infrun: TARGET_WAITKIND_NO_RESUMED "
4795 "(expect process exit)\n");
4796 prepare_to_wait (ecs
);
4801 /* Go ahead and report the event. */
4805 /* Given an execution control state that has been freshly filled in by
4806 an event from the inferior, figure out what it means and take
4809 The alternatives are:
4811 1) stop_waiting and return; to really stop and return to the
4814 2) keep_going and return; to wait for the next event (set
4815 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4819 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4821 enum stop_kind stop_soon
;
4823 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4825 /* We had an event in the inferior, but we are not interested in
4826 handling it at this level. The lower layers have already
4827 done what needs to be done, if anything.
4829 One of the possible circumstances for this is when the
4830 inferior produces output for the console. The inferior has
4831 not stopped, and we are ignoring the event. Another possible
4832 circumstance is any event which the lower level knows will be
4833 reported multiple times without an intervening resume. */
4835 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4836 prepare_to_wait (ecs
);
4840 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4843 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4844 prepare_to_wait (ecs
);
4848 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4849 && handle_no_resumed (ecs
))
4852 /* Cache the last pid/waitstatus. */
4853 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4855 /* Always clear state belonging to the previous time we stopped. */
4856 stop_stack_dummy
= STOP_NONE
;
4858 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4860 /* No unwaited-for children left. IOW, all resumed children
4863 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4865 stop_print_frame
= 0;
4870 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4871 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4873 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4874 /* If it's a new thread, add it to the thread database. */
4875 if (ecs
->event_thread
== NULL
)
4876 ecs
->event_thread
= add_thread (ecs
->ptid
);
4878 /* Disable range stepping. If the next step request could use a
4879 range, this will be end up re-enabled then. */
4880 ecs
->event_thread
->control
.may_range_step
= 0;
4883 /* Dependent on valid ECS->EVENT_THREAD. */
4884 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4886 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4887 reinit_frame_cache ();
4889 breakpoint_retire_moribund ();
4891 /* First, distinguish signals caused by the debugger from signals
4892 that have to do with the program's own actions. Note that
4893 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4894 on the operating system version. Here we detect when a SIGILL or
4895 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4896 something similar for SIGSEGV, since a SIGSEGV will be generated
4897 when we're trying to execute a breakpoint instruction on a
4898 non-executable stack. This happens for call dummy breakpoints
4899 for architectures like SPARC that place call dummies on the
4901 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4902 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4903 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4904 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4906 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4908 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
4909 regcache_read_pc (regcache
)))
4912 fprintf_unfiltered (gdb_stdlog
,
4913 "infrun: Treating signal as SIGTRAP\n");
4914 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4918 /* Mark the non-executing threads accordingly. In all-stop, all
4919 threads of all processes are stopped when we get any event
4920 reported. In non-stop mode, only the event thread stops. */
4924 if (!target_is_non_stop_p ())
4925 mark_ptid
= minus_one_ptid
;
4926 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4927 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4929 /* If we're handling a process exit in non-stop mode, even
4930 though threads haven't been deleted yet, one would think
4931 that there is nothing to do, as threads of the dead process
4932 will be soon deleted, and threads of any other process were
4933 left running. However, on some targets, threads survive a
4934 process exit event. E.g., for the "checkpoint" command,
4935 when the current checkpoint/fork exits, linux-fork.c
4936 automatically switches to another fork from within
4937 target_mourn_inferior, by associating the same
4938 inferior/thread to another fork. We haven't mourned yet at
4939 this point, but we must mark any threads left in the
4940 process as not-executing so that finish_thread_state marks
4941 them stopped (in the user's perspective) if/when we present
4942 the stop to the user. */
4943 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4946 mark_ptid
= ecs
->ptid
;
4948 set_executing (mark_ptid
, 0);
4950 /* Likewise the resumed flag. */
4951 set_resumed (mark_ptid
, 0);
4954 switch (ecs
->ws
.kind
)
4956 case TARGET_WAITKIND_LOADED
:
4958 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4959 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4960 context_switch (ecs
->ptid
);
4961 /* Ignore gracefully during startup of the inferior, as it might
4962 be the shell which has just loaded some objects, otherwise
4963 add the symbols for the newly loaded objects. Also ignore at
4964 the beginning of an attach or remote session; we will query
4965 the full list of libraries once the connection is
4968 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4969 if (stop_soon
== NO_STOP_QUIETLY
)
4971 struct regcache
*regcache
;
4973 regcache
= get_thread_regcache (ecs
->ptid
);
4975 handle_solib_event ();
4977 ecs
->event_thread
->control
.stop_bpstat
4978 = bpstat_stop_status (get_regcache_aspace (regcache
),
4979 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4981 if (handle_stop_requested (ecs
))
4984 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4986 /* A catchpoint triggered. */
4987 process_event_stop_test (ecs
);
4991 /* If requested, stop when the dynamic linker notifies
4992 gdb of events. This allows the user to get control
4993 and place breakpoints in initializer routines for
4994 dynamically loaded objects (among other things). */
4995 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4996 if (stop_on_solib_events
)
4998 /* Make sure we print "Stopped due to solib-event" in
5000 stop_print_frame
= 1;
5007 /* If we are skipping through a shell, or through shared library
5008 loading that we aren't interested in, resume the program. If
5009 we're running the program normally, also resume. */
5010 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5012 /* Loading of shared libraries might have changed breakpoint
5013 addresses. Make sure new breakpoints are inserted. */
5014 if (stop_soon
== NO_STOP_QUIETLY
)
5015 insert_breakpoints ();
5016 resume (GDB_SIGNAL_0
);
5017 prepare_to_wait (ecs
);
5021 /* But stop if we're attaching or setting up a remote
5023 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5024 || stop_soon
== STOP_QUIETLY_REMOTE
)
5027 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5032 internal_error (__FILE__
, __LINE__
,
5033 _("unhandled stop_soon: %d"), (int) stop_soon
);
5035 case TARGET_WAITKIND_SPURIOUS
:
5037 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
5038 if (handle_stop_requested (ecs
))
5040 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5041 context_switch (ecs
->ptid
);
5042 resume (GDB_SIGNAL_0
);
5043 prepare_to_wait (ecs
);
5046 case TARGET_WAITKIND_THREAD_CREATED
:
5048 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
5049 if (handle_stop_requested (ecs
))
5051 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5052 context_switch (ecs
->ptid
);
5053 if (!switch_back_to_stepped_thread (ecs
))
5057 case TARGET_WAITKIND_EXITED
:
5058 case TARGET_WAITKIND_SIGNALLED
:
5061 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5062 fprintf_unfiltered (gdb_stdlog
,
5063 "infrun: TARGET_WAITKIND_EXITED\n");
5065 fprintf_unfiltered (gdb_stdlog
,
5066 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5069 inferior_ptid
= ecs
->ptid
;
5070 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
5071 set_current_program_space (current_inferior ()->pspace
);
5072 handle_vfork_child_exec_or_exit (0);
5073 target_terminal_ours (); /* Must do this before mourn anyway. */
5075 /* Clearing any previous state of convenience variables. */
5076 clear_exit_convenience_vars ();
5078 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5080 /* Record the exit code in the convenience variable $_exitcode, so
5081 that the user can inspect this again later. */
5082 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5083 (LONGEST
) ecs
->ws
.value
.integer
);
5085 /* Also record this in the inferior itself. */
5086 current_inferior ()->has_exit_code
= 1;
5087 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5089 /* Support the --return-child-result option. */
5090 return_child_result_value
= ecs
->ws
.value
.integer
;
5092 observer_notify_exited (ecs
->ws
.value
.integer
);
5096 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5097 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5099 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5101 /* Set the value of the internal variable $_exitsignal,
5102 which holds the signal uncaught by the inferior. */
5103 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5104 gdbarch_gdb_signal_to_target (gdbarch
,
5105 ecs
->ws
.value
.sig
));
5109 /* We don't have access to the target's method used for
5110 converting between signal numbers (GDB's internal
5111 representation <-> target's representation).
5112 Therefore, we cannot do a good job at displaying this
5113 information to the user. It's better to just warn
5114 her about it (if infrun debugging is enabled), and
5117 fprintf_filtered (gdb_stdlog
, _("\
5118 Cannot fill $_exitsignal with the correct signal number.\n"));
5121 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
5124 gdb_flush (gdb_stdout
);
5125 target_mourn_inferior (inferior_ptid
);
5126 stop_print_frame
= 0;
5130 /* The following are the only cases in which we keep going;
5131 the above cases end in a continue or goto. */
5132 case TARGET_WAITKIND_FORKED
:
5133 case TARGET_WAITKIND_VFORKED
:
5136 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5137 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
5139 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
5142 /* Check whether the inferior is displaced stepping. */
5144 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5145 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5147 /* If checking displaced stepping is supported, and thread
5148 ecs->ptid is displaced stepping. */
5149 if (displaced_step_in_progress_thread (ecs
->ptid
))
5151 struct inferior
*parent_inf
5152 = find_inferior_ptid (ecs
->ptid
);
5153 struct regcache
*child_regcache
;
5154 CORE_ADDR parent_pc
;
5156 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5157 indicating that the displaced stepping of syscall instruction
5158 has been done. Perform cleanup for parent process here. Note
5159 that this operation also cleans up the child process for vfork,
5160 because their pages are shared. */
5161 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
5162 /* Start a new step-over in another thread if there's one
5166 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5168 struct displaced_step_inferior_state
*displaced
5169 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
5171 /* Restore scratch pad for child process. */
5172 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
5175 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5176 the child's PC is also within the scratchpad. Set the child's PC
5177 to the parent's PC value, which has already been fixed up.
5178 FIXME: we use the parent's aspace here, although we're touching
5179 the child, because the child hasn't been added to the inferior
5180 list yet at this point. */
5183 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
5185 parent_inf
->aspace
);
5186 /* Read PC value of parent process. */
5187 parent_pc
= regcache_read_pc (regcache
);
5189 if (debug_displaced
)
5190 fprintf_unfiltered (gdb_stdlog
,
5191 "displaced: write child pc from %s to %s\n",
5193 regcache_read_pc (child_regcache
)),
5194 paddress (gdbarch
, parent_pc
));
5196 regcache_write_pc (child_regcache
, parent_pc
);
5200 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5201 context_switch (ecs
->ptid
);
5203 /* Immediately detach breakpoints from the child before there's
5204 any chance of letting the user delete breakpoints from the
5205 breakpoint lists. If we don't do this early, it's easy to
5206 leave left over traps in the child, vis: "break foo; catch
5207 fork; c; <fork>; del; c; <child calls foo>". We only follow
5208 the fork on the last `continue', and by that time the
5209 breakpoint at "foo" is long gone from the breakpoint table.
5210 If we vforked, then we don't need to unpatch here, since both
5211 parent and child are sharing the same memory pages; we'll
5212 need to unpatch at follow/detach time instead to be certain
5213 that new breakpoints added between catchpoint hit time and
5214 vfork follow are detached. */
5215 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5217 /* This won't actually modify the breakpoint list, but will
5218 physically remove the breakpoints from the child. */
5219 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5222 delete_just_stopped_threads_single_step_breakpoints ();
5224 /* In case the event is caught by a catchpoint, remember that
5225 the event is to be followed at the next resume of the thread,
5226 and not immediately. */
5227 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5229 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5231 ecs
->event_thread
->control
.stop_bpstat
5232 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5233 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5235 if (handle_stop_requested (ecs
))
5238 /* If no catchpoint triggered for this, then keep going. Note
5239 that we're interested in knowing the bpstat actually causes a
5240 stop, not just if it may explain the signal. Software
5241 watchpoints, for example, always appear in the bpstat. */
5242 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5248 = (follow_fork_mode_string
== follow_fork_mode_child
);
5250 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5252 should_resume
= follow_fork ();
5255 child
= ecs
->ws
.value
.related_pid
;
5257 /* At this point, the parent is marked running, and the
5258 child is marked stopped. */
5260 /* If not resuming the parent, mark it stopped. */
5261 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5262 set_running (parent
, 0);
5264 /* If resuming the child, mark it running. */
5265 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5266 set_running (child
, 1);
5268 /* In non-stop mode, also resume the other branch. */
5269 if (!detach_fork
&& (non_stop
5270 || (sched_multi
&& target_is_non_stop_p ())))
5273 switch_to_thread (parent
);
5275 switch_to_thread (child
);
5277 ecs
->event_thread
= inferior_thread ();
5278 ecs
->ptid
= inferior_ptid
;
5283 switch_to_thread (child
);
5285 switch_to_thread (parent
);
5287 ecs
->event_thread
= inferior_thread ();
5288 ecs
->ptid
= inferior_ptid
;
5296 process_event_stop_test (ecs
);
5299 case TARGET_WAITKIND_VFORK_DONE
:
5300 /* Done with the shared memory region. Re-insert breakpoints in
5301 the parent, and keep going. */
5304 fprintf_unfiltered (gdb_stdlog
,
5305 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5307 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5308 context_switch (ecs
->ptid
);
5310 current_inferior ()->waiting_for_vfork_done
= 0;
5311 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5313 if (handle_stop_requested (ecs
))
5316 /* This also takes care of reinserting breakpoints in the
5317 previously locked inferior. */
5321 case TARGET_WAITKIND_EXECD
:
5323 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5325 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5326 context_switch (ecs
->ptid
);
5328 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5330 /* Do whatever is necessary to the parent branch of the vfork. */
5331 handle_vfork_child_exec_or_exit (1);
5333 /* This causes the eventpoints and symbol table to be reset.
5334 Must do this now, before trying to determine whether to
5336 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5338 /* In follow_exec we may have deleted the original thread and
5339 created a new one. Make sure that the event thread is the
5340 execd thread for that case (this is a nop otherwise). */
5341 ecs
->event_thread
= inferior_thread ();
5343 ecs
->event_thread
->control
.stop_bpstat
5344 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5345 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5347 /* Note that this may be referenced from inside
5348 bpstat_stop_status above, through inferior_has_execd. */
5349 xfree (ecs
->ws
.value
.execd_pathname
);
5350 ecs
->ws
.value
.execd_pathname
= NULL
;
5352 if (handle_stop_requested (ecs
))
5355 /* If no catchpoint triggered for this, then keep going. */
5356 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5358 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5362 process_event_stop_test (ecs
);
5365 /* Be careful not to try to gather much state about a thread
5366 that's in a syscall. It's frequently a losing proposition. */
5367 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5369 fprintf_unfiltered (gdb_stdlog
,
5370 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5371 /* Getting the current syscall number. */
5372 if (handle_syscall_event (ecs
) == 0)
5373 process_event_stop_test (ecs
);
5376 /* Before examining the threads further, step this thread to
5377 get it entirely out of the syscall. (We get notice of the
5378 event when the thread is just on the verge of exiting a
5379 syscall. Stepping one instruction seems to get it back
5381 case TARGET_WAITKIND_SYSCALL_RETURN
:
5383 fprintf_unfiltered (gdb_stdlog
,
5384 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5385 if (handle_syscall_event (ecs
) == 0)
5386 process_event_stop_test (ecs
);
5389 case TARGET_WAITKIND_STOPPED
:
5391 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5392 handle_signal_stop (ecs
);
5395 case TARGET_WAITKIND_NO_HISTORY
:
5397 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5398 /* Reverse execution: target ran out of history info. */
5400 /* Switch to the stopped thread. */
5401 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5402 context_switch (ecs
->ptid
);
5404 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5406 delete_just_stopped_threads_single_step_breakpoints ();
5407 stop_pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
5409 if (handle_stop_requested (ecs
))
5412 observer_notify_no_history ();
5418 /* A wrapper around handle_inferior_event_1, which also makes sure
5419 that all temporary struct value objects that were created during
5420 the handling of the event get deleted at the end. */
5423 handle_inferior_event (struct execution_control_state
*ecs
)
5425 struct value
*mark
= value_mark ();
5427 handle_inferior_event_1 (ecs
);
5428 /* Purge all temporary values created during the event handling,
5429 as it could be a long time before we return to the command level
5430 where such values would otherwise be purged. */
5431 value_free_to_mark (mark
);
5434 /* Restart threads back to what they were trying to do back when we
5435 paused them for an in-line step-over. The EVENT_THREAD thread is
5439 restart_threads (struct thread_info
*event_thread
)
5441 struct thread_info
*tp
;
5443 /* In case the instruction just stepped spawned a new thread. */
5444 update_thread_list ();
5446 ALL_NON_EXITED_THREADS (tp
)
5448 if (tp
== event_thread
)
5451 fprintf_unfiltered (gdb_stdlog
,
5452 "infrun: restart threads: "
5453 "[%s] is event thread\n",
5454 target_pid_to_str (tp
->ptid
));
5458 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5461 fprintf_unfiltered (gdb_stdlog
,
5462 "infrun: restart threads: "
5463 "[%s] not meant to be running\n",
5464 target_pid_to_str (tp
->ptid
));
5471 fprintf_unfiltered (gdb_stdlog
,
5472 "infrun: restart threads: [%s] resumed\n",
5473 target_pid_to_str (tp
->ptid
));
5474 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5478 if (thread_is_in_step_over_chain (tp
))
5481 fprintf_unfiltered (gdb_stdlog
,
5482 "infrun: restart threads: "
5483 "[%s] needs step-over\n",
5484 target_pid_to_str (tp
->ptid
));
5485 gdb_assert (!tp
->resumed
);
5490 if (tp
->suspend
.waitstatus_pending_p
)
5493 fprintf_unfiltered (gdb_stdlog
,
5494 "infrun: restart threads: "
5495 "[%s] has pending status\n",
5496 target_pid_to_str (tp
->ptid
));
5501 gdb_assert (!tp
->stop_requested
);
5503 /* If some thread needs to start a step-over at this point, it
5504 should still be in the step-over queue, and thus skipped
5506 if (thread_still_needs_step_over (tp
))
5508 internal_error (__FILE__
, __LINE__
,
5509 "thread [%s] needs a step-over, but not in "
5510 "step-over queue\n",
5511 target_pid_to_str (tp
->ptid
));
5514 if (currently_stepping (tp
))
5517 fprintf_unfiltered (gdb_stdlog
,
5518 "infrun: restart threads: [%s] was stepping\n",
5519 target_pid_to_str (tp
->ptid
));
5520 keep_going_stepped_thread (tp
);
5524 struct execution_control_state ecss
;
5525 struct execution_control_state
*ecs
= &ecss
;
5528 fprintf_unfiltered (gdb_stdlog
,
5529 "infrun: restart threads: [%s] continuing\n",
5530 target_pid_to_str (tp
->ptid
));
5531 reset_ecs (ecs
, tp
);
5532 switch_to_thread (tp
->ptid
);
5533 keep_going_pass_signal (ecs
);
5538 /* Callback for iterate_over_threads. Find a resumed thread that has
5539 a pending waitstatus. */
5542 resumed_thread_with_pending_status (struct thread_info
*tp
,
5546 && tp
->suspend
.waitstatus_pending_p
);
5549 /* Called when we get an event that may finish an in-line or
5550 out-of-line (displaced stepping) step-over started previously.
5551 Return true if the event is processed and we should go back to the
5552 event loop; false if the caller should continue processing the
5556 finish_step_over (struct execution_control_state
*ecs
)
5558 int had_step_over_info
;
5560 displaced_step_fixup (ecs
->ptid
,
5561 ecs
->event_thread
->suspend
.stop_signal
);
5563 had_step_over_info
= step_over_info_valid_p ();
5565 if (had_step_over_info
)
5567 /* If we're stepping over a breakpoint with all threads locked,
5568 then only the thread that was stepped should be reporting
5570 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5572 clear_step_over_info ();
5575 if (!target_is_non_stop_p ())
5578 /* Start a new step-over in another thread if there's one that
5582 /* If we were stepping over a breakpoint before, and haven't started
5583 a new in-line step-over sequence, then restart all other threads
5584 (except the event thread). We can't do this in all-stop, as then
5585 e.g., we wouldn't be able to issue any other remote packet until
5586 these other threads stop. */
5587 if (had_step_over_info
&& !step_over_info_valid_p ())
5589 struct thread_info
*pending
;
5591 /* If we only have threads with pending statuses, the restart
5592 below won't restart any thread and so nothing re-inserts the
5593 breakpoint we just stepped over. But we need it inserted
5594 when we later process the pending events, otherwise if
5595 another thread has a pending event for this breakpoint too,
5596 we'd discard its event (because the breakpoint that
5597 originally caused the event was no longer inserted). */
5598 context_switch (ecs
->ptid
);
5599 insert_breakpoints ();
5601 restart_threads (ecs
->event_thread
);
5603 /* If we have events pending, go through handle_inferior_event
5604 again, picking up a pending event at random. This avoids
5605 thread starvation. */
5607 /* But not if we just stepped over a watchpoint in order to let
5608 the instruction execute so we can evaluate its expression.
5609 The set of watchpoints that triggered is recorded in the
5610 breakpoint objects themselves (see bp->watchpoint_triggered).
5611 If we processed another event first, that other event could
5612 clobber this info. */
5613 if (ecs
->event_thread
->stepping_over_watchpoint
)
5616 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5618 if (pending
!= NULL
)
5620 struct thread_info
*tp
= ecs
->event_thread
;
5621 struct regcache
*regcache
;
5625 fprintf_unfiltered (gdb_stdlog
,
5626 "infrun: found resumed threads with "
5627 "pending events, saving status\n");
5630 gdb_assert (pending
!= tp
);
5632 /* Record the event thread's event for later. */
5633 save_waitstatus (tp
, &ecs
->ws
);
5634 /* This was cleared early, by handle_inferior_event. Set it
5635 so this pending event is considered by
5639 gdb_assert (!tp
->executing
);
5641 regcache
= get_thread_regcache (tp
->ptid
);
5642 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5646 fprintf_unfiltered (gdb_stdlog
,
5647 "infrun: saved stop_pc=%s for %s "
5648 "(currently_stepping=%d)\n",
5649 paddress (target_gdbarch (),
5650 tp
->suspend
.stop_pc
),
5651 target_pid_to_str (tp
->ptid
),
5652 currently_stepping (tp
));
5655 /* This in-line step-over finished; clear this so we won't
5656 start a new one. This is what handle_signal_stop would
5657 do, if we returned false. */
5658 tp
->stepping_over_breakpoint
= 0;
5660 /* Wake up the event loop again. */
5661 mark_async_event_handler (infrun_async_inferior_event_token
);
5663 prepare_to_wait (ecs
);
5671 /* Come here when the program has stopped with a signal. */
5674 handle_signal_stop (struct execution_control_state
*ecs
)
5676 struct frame_info
*frame
;
5677 struct gdbarch
*gdbarch
;
5678 int stopped_by_watchpoint
;
5679 enum stop_kind stop_soon
;
5682 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5684 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5686 /* Do we need to clean up the state of a thread that has
5687 completed a displaced single-step? (Doing so usually affects
5688 the PC, so do it here, before we set stop_pc.) */
5689 if (finish_step_over (ecs
))
5692 /* If we either finished a single-step or hit a breakpoint, but
5693 the user wanted this thread to be stopped, pretend we got a
5694 SIG0 (generic unsignaled stop). */
5695 if (ecs
->event_thread
->stop_requested
5696 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5697 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5699 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5703 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5704 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5705 struct cleanup
*old_chain
= save_inferior_ptid ();
5707 inferior_ptid
= ecs
->ptid
;
5709 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5710 paddress (gdbarch
, stop_pc
));
5711 if (target_stopped_by_watchpoint ())
5715 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5717 if (target_stopped_data_address (¤t_target
, &addr
))
5718 fprintf_unfiltered (gdb_stdlog
,
5719 "infrun: stopped data address = %s\n",
5720 paddress (gdbarch
, addr
));
5722 fprintf_unfiltered (gdb_stdlog
,
5723 "infrun: (no data address available)\n");
5726 do_cleanups (old_chain
);
5729 /* This is originated from start_remote(), start_inferior() and
5730 shared libraries hook functions. */
5731 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5732 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5734 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5735 context_switch (ecs
->ptid
);
5737 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5738 stop_print_frame
= 1;
5743 /* This originates from attach_command(). We need to overwrite
5744 the stop_signal here, because some kernels don't ignore a
5745 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5746 See more comments in inferior.h. On the other hand, if we
5747 get a non-SIGSTOP, report it to the user - assume the backend
5748 will handle the SIGSTOP if it should show up later.
5750 Also consider that the attach is complete when we see a
5751 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5752 target extended-remote report it instead of a SIGSTOP
5753 (e.g. gdbserver). We already rely on SIGTRAP being our
5754 signal, so this is no exception.
5756 Also consider that the attach is complete when we see a
5757 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5758 the target to stop all threads of the inferior, in case the
5759 low level attach operation doesn't stop them implicitly. If
5760 they weren't stopped implicitly, then the stub will report a
5761 GDB_SIGNAL_0, meaning: stopped for no particular reason
5762 other than GDB's request. */
5763 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5764 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5765 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5766 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5768 stop_print_frame
= 1;
5770 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5774 /* See if something interesting happened to the non-current thread. If
5775 so, then switch to that thread. */
5776 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5779 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5781 context_switch (ecs
->ptid
);
5783 if (deprecated_context_hook
)
5784 deprecated_context_hook (ptid_to_global_thread_id (ecs
->ptid
));
5787 /* At this point, get hold of the now-current thread's frame. */
5788 frame
= get_current_frame ();
5789 gdbarch
= get_frame_arch (frame
);
5791 /* Pull the single step breakpoints out of the target. */
5792 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5794 struct regcache
*regcache
;
5795 struct address_space
*aspace
;
5798 regcache
= get_thread_regcache (ecs
->ptid
);
5799 aspace
= get_regcache_aspace (regcache
);
5800 pc
= regcache_read_pc (regcache
);
5802 /* However, before doing so, if this single-step breakpoint was
5803 actually for another thread, set this thread up for moving
5805 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5808 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5812 fprintf_unfiltered (gdb_stdlog
,
5813 "infrun: [%s] hit another thread's "
5814 "single-step breakpoint\n",
5815 target_pid_to_str (ecs
->ptid
));
5817 ecs
->hit_singlestep_breakpoint
= 1;
5824 fprintf_unfiltered (gdb_stdlog
,
5825 "infrun: [%s] hit its "
5826 "single-step breakpoint\n",
5827 target_pid_to_str (ecs
->ptid
));
5831 delete_just_stopped_threads_single_step_breakpoints ();
5833 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5834 && ecs
->event_thread
->control
.trap_expected
5835 && ecs
->event_thread
->stepping_over_watchpoint
)
5836 stopped_by_watchpoint
= 0;
5838 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5840 /* If necessary, step over this watchpoint. We'll be back to display
5842 if (stopped_by_watchpoint
5843 && (target_have_steppable_watchpoint
5844 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5846 /* At this point, we are stopped at an instruction which has
5847 attempted to write to a piece of memory under control of
5848 a watchpoint. The instruction hasn't actually executed
5849 yet. If we were to evaluate the watchpoint expression
5850 now, we would get the old value, and therefore no change
5851 would seem to have occurred.
5853 In order to make watchpoints work `right', we really need
5854 to complete the memory write, and then evaluate the
5855 watchpoint expression. We do this by single-stepping the
5858 It may not be necessary to disable the watchpoint to step over
5859 it. For example, the PA can (with some kernel cooperation)
5860 single step over a watchpoint without disabling the watchpoint.
5862 It is far more common to need to disable a watchpoint to step
5863 the inferior over it. If we have non-steppable watchpoints,
5864 we must disable the current watchpoint; it's simplest to
5865 disable all watchpoints.
5867 Any breakpoint at PC must also be stepped over -- if there's
5868 one, it will have already triggered before the watchpoint
5869 triggered, and we either already reported it to the user, or
5870 it didn't cause a stop and we called keep_going. In either
5871 case, if there was a breakpoint at PC, we must be trying to
5873 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5878 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5879 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5880 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5881 ecs
->event_thread
->control
.stop_step
= 0;
5882 stop_print_frame
= 1;
5883 stopped_by_random_signal
= 0;
5885 /* Hide inlined functions starting here, unless we just performed stepi or
5886 nexti. After stepi and nexti, always show the innermost frame (not any
5887 inline function call sites). */
5888 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5890 struct address_space
*aspace
=
5891 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
5893 /* skip_inline_frames is expensive, so we avoid it if we can
5894 determine that the address is one where functions cannot have
5895 been inlined. This improves performance with inferiors that
5896 load a lot of shared libraries, because the solib event
5897 breakpoint is defined as the address of a function (i.e. not
5898 inline). Note that we have to check the previous PC as well
5899 as the current one to catch cases when we have just
5900 single-stepped off a breakpoint prior to reinstating it.
5901 Note that we're assuming that the code we single-step to is
5902 not inline, but that's not definitive: there's nothing
5903 preventing the event breakpoint function from containing
5904 inlined code, and the single-step ending up there. If the
5905 user had set a breakpoint on that inlined code, the missing
5906 skip_inline_frames call would break things. Fortunately
5907 that's an extremely unlikely scenario. */
5908 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5909 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5910 && ecs
->event_thread
->control
.trap_expected
5911 && pc_at_non_inline_function (aspace
,
5912 ecs
->event_thread
->prev_pc
,
5915 skip_inline_frames (ecs
->ptid
);
5917 /* Re-fetch current thread's frame in case that invalidated
5919 frame
= get_current_frame ();
5920 gdbarch
= get_frame_arch (frame
);
5924 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5925 && ecs
->event_thread
->control
.trap_expected
5926 && gdbarch_single_step_through_delay_p (gdbarch
)
5927 && currently_stepping (ecs
->event_thread
))
5929 /* We're trying to step off a breakpoint. Turns out that we're
5930 also on an instruction that needs to be stepped multiple
5931 times before it's been fully executing. E.g., architectures
5932 with a delay slot. It needs to be stepped twice, once for
5933 the instruction and once for the delay slot. */
5934 int step_through_delay
5935 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5937 if (debug_infrun
&& step_through_delay
)
5938 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5939 if (ecs
->event_thread
->control
.step_range_end
== 0
5940 && step_through_delay
)
5942 /* The user issued a continue when stopped at a breakpoint.
5943 Set up for another trap and get out of here. */
5944 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5948 else if (step_through_delay
)
5950 /* The user issued a step when stopped at a breakpoint.
5951 Maybe we should stop, maybe we should not - the delay
5952 slot *might* correspond to a line of source. In any
5953 case, don't decide that here, just set
5954 ecs->stepping_over_breakpoint, making sure we
5955 single-step again before breakpoints are re-inserted. */
5956 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5960 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5961 handles this event. */
5962 ecs
->event_thread
->control
.stop_bpstat
5963 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5964 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5966 /* Following in case break condition called a
5968 stop_print_frame
= 1;
5970 /* This is where we handle "moribund" watchpoints. Unlike
5971 software breakpoints traps, hardware watchpoint traps are
5972 always distinguishable from random traps. If no high-level
5973 watchpoint is associated with the reported stop data address
5974 anymore, then the bpstat does not explain the signal ---
5975 simply make sure to ignore it if `stopped_by_watchpoint' is
5979 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5980 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5982 && stopped_by_watchpoint
)
5983 fprintf_unfiltered (gdb_stdlog
,
5984 "infrun: no user watchpoint explains "
5985 "watchpoint SIGTRAP, ignoring\n");
5987 /* NOTE: cagney/2003-03-29: These checks for a random signal
5988 at one stage in the past included checks for an inferior
5989 function call's call dummy's return breakpoint. The original
5990 comment, that went with the test, read:
5992 ``End of a stack dummy. Some systems (e.g. Sony news) give
5993 another signal besides SIGTRAP, so check here as well as
5996 If someone ever tries to get call dummys on a
5997 non-executable stack to work (where the target would stop
5998 with something like a SIGSEGV), then those tests might need
5999 to be re-instated. Given, however, that the tests were only
6000 enabled when momentary breakpoints were not being used, I
6001 suspect that it won't be the case.
6003 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
6004 be necessary for call dummies on a non-executable stack on
6007 /* See if the breakpoints module can explain the signal. */
6009 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6010 ecs
->event_thread
->suspend
.stop_signal
);
6012 /* Maybe this was a trap for a software breakpoint that has since
6014 if (random_signal
&& target_stopped_by_sw_breakpoint ())
6016 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
6018 struct regcache
*regcache
;
6021 /* Re-adjust PC to what the program would see if GDB was not
6023 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
6024 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6027 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
6029 if (record_full_is_used ())
6030 record_full_gdb_operation_disable_set ();
6032 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
6034 do_cleanups (old_cleanups
);
6039 /* A delayed software breakpoint event. Ignore the trap. */
6041 fprintf_unfiltered (gdb_stdlog
,
6042 "infrun: delayed software breakpoint "
6043 "trap, ignoring\n");
6048 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6049 has since been removed. */
6050 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6052 /* A delayed hardware breakpoint event. Ignore the trap. */
6054 fprintf_unfiltered (gdb_stdlog
,
6055 "infrun: delayed hardware breakpoint/watchpoint "
6056 "trap, ignoring\n");
6060 /* If not, perhaps stepping/nexting can. */
6062 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6063 && currently_stepping (ecs
->event_thread
));
6065 /* Perhaps the thread hit a single-step breakpoint of _another_
6066 thread. Single-step breakpoints are transparent to the
6067 breakpoints module. */
6069 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6071 /* No? Perhaps we got a moribund watchpoint. */
6073 random_signal
= !stopped_by_watchpoint
;
6075 /* Always stop if the user explicitly requested this thread to
6077 if (ecs
->event_thread
->stop_requested
)
6081 fprintf_unfiltered (gdb_stdlog
, "infrun: user-requested stop\n");
6084 /* For the program's own signals, act according to
6085 the signal handling tables. */
6089 /* Signal not for debugging purposes. */
6090 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
6091 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6094 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
6095 gdb_signal_to_symbol_string (stop_signal
));
6097 stopped_by_random_signal
= 1;
6099 /* Always stop on signals if we're either just gaining control
6100 of the program, or the user explicitly requested this thread
6101 to remain stopped. */
6102 if (stop_soon
!= NO_STOP_QUIETLY
6103 || ecs
->event_thread
->stop_requested
6105 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
6111 /* Notify observers the signal has "handle print" set. Note we
6112 returned early above if stopping; normal_stop handles the
6113 printing in that case. */
6114 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6116 /* The signal table tells us to print about this signal. */
6117 target_terminal_ours_for_output ();
6118 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
6119 target_terminal_inferior ();
6122 /* Clear the signal if it should not be passed. */
6123 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6124 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6126 if (ecs
->event_thread
->prev_pc
== stop_pc
6127 && ecs
->event_thread
->control
.trap_expected
6128 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6130 /* We were just starting a new sequence, attempting to
6131 single-step off of a breakpoint and expecting a SIGTRAP.
6132 Instead this signal arrives. This signal will take us out
6133 of the stepping range so GDB needs to remember to, when
6134 the signal handler returns, resume stepping off that
6136 /* To simplify things, "continue" is forced to use the same
6137 code paths as single-step - set a breakpoint at the
6138 signal return address and then, once hit, step off that
6141 fprintf_unfiltered (gdb_stdlog
,
6142 "infrun: signal arrived while stepping over "
6145 insert_hp_step_resume_breakpoint_at_frame (frame
);
6146 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6147 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6148 ecs
->event_thread
->control
.trap_expected
= 0;
6150 /* If we were nexting/stepping some other thread, switch to
6151 it, so that we don't continue it, losing control. */
6152 if (!switch_back_to_stepped_thread (ecs
))
6157 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6158 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6159 || ecs
->event_thread
->control
.step_range_end
== 1)
6160 && frame_id_eq (get_stack_frame_id (frame
),
6161 ecs
->event_thread
->control
.step_stack_frame_id
)
6162 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6164 /* The inferior is about to take a signal that will take it
6165 out of the single step range. Set a breakpoint at the
6166 current PC (which is presumably where the signal handler
6167 will eventually return) and then allow the inferior to
6170 Note that this is only needed for a signal delivered
6171 while in the single-step range. Nested signals aren't a
6172 problem as they eventually all return. */
6174 fprintf_unfiltered (gdb_stdlog
,
6175 "infrun: signal may take us out of "
6176 "single-step range\n");
6178 clear_step_over_info ();
6179 insert_hp_step_resume_breakpoint_at_frame (frame
);
6180 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6181 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6182 ecs
->event_thread
->control
.trap_expected
= 0;
6187 /* Note: step_resume_breakpoint may be non-NULL. This occures
6188 when either there's a nested signal, or when there's a
6189 pending signal enabled just as the signal handler returns
6190 (leaving the inferior at the step-resume-breakpoint without
6191 actually executing it). Either way continue until the
6192 breakpoint is really hit. */
6194 if (!switch_back_to_stepped_thread (ecs
))
6197 fprintf_unfiltered (gdb_stdlog
,
6198 "infrun: random signal, keep going\n");
6205 process_event_stop_test (ecs
);
6208 /* Come here when we've got some debug event / signal we can explain
6209 (IOW, not a random signal), and test whether it should cause a
6210 stop, or whether we should resume the inferior (transparently).
6211 E.g., could be a breakpoint whose condition evaluates false; we
6212 could be still stepping within the line; etc. */
6215 process_event_stop_test (struct execution_control_state
*ecs
)
6217 struct symtab_and_line stop_pc_sal
;
6218 struct frame_info
*frame
;
6219 struct gdbarch
*gdbarch
;
6220 CORE_ADDR jmp_buf_pc
;
6221 struct bpstat_what what
;
6223 /* Handle cases caused by hitting a breakpoint. */
6225 frame
= get_current_frame ();
6226 gdbarch
= get_frame_arch (frame
);
6228 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6230 if (what
.call_dummy
)
6232 stop_stack_dummy
= what
.call_dummy
;
6235 /* A few breakpoint types have callbacks associated (e.g.,
6236 bp_jit_event). Run them now. */
6237 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6239 /* If we hit an internal event that triggers symbol changes, the
6240 current frame will be invalidated within bpstat_what (e.g., if we
6241 hit an internal solib event). Re-fetch it. */
6242 frame
= get_current_frame ();
6243 gdbarch
= get_frame_arch (frame
);
6245 switch (what
.main_action
)
6247 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6248 /* If we hit the breakpoint at longjmp while stepping, we
6249 install a momentary breakpoint at the target of the
6253 fprintf_unfiltered (gdb_stdlog
,
6254 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6256 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6258 if (what
.is_longjmp
)
6260 struct value
*arg_value
;
6262 /* If we set the longjmp breakpoint via a SystemTap probe,
6263 then use it to extract the arguments. The destination PC
6264 is the third argument to the probe. */
6265 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6268 jmp_buf_pc
= value_as_address (arg_value
);
6269 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6271 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6272 || !gdbarch_get_longjmp_target (gdbarch
,
6273 frame
, &jmp_buf_pc
))
6276 fprintf_unfiltered (gdb_stdlog
,
6277 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6278 "(!gdbarch_get_longjmp_target)\n");
6283 /* Insert a breakpoint at resume address. */
6284 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6287 check_exception_resume (ecs
, frame
);
6291 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6293 struct frame_info
*init_frame
;
6295 /* There are several cases to consider.
6297 1. The initiating frame no longer exists. In this case we
6298 must stop, because the exception or longjmp has gone too
6301 2. The initiating frame exists, and is the same as the
6302 current frame. We stop, because the exception or longjmp
6305 3. The initiating frame exists and is different from the
6306 current frame. This means the exception or longjmp has
6307 been caught beneath the initiating frame, so keep going.
6309 4. longjmp breakpoint has been placed just to protect
6310 against stale dummy frames and user is not interested in
6311 stopping around longjmps. */
6314 fprintf_unfiltered (gdb_stdlog
,
6315 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6317 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6319 delete_exception_resume_breakpoint (ecs
->event_thread
);
6321 if (what
.is_longjmp
)
6323 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6325 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6333 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6337 struct frame_id current_id
6338 = get_frame_id (get_current_frame ());
6339 if (frame_id_eq (current_id
,
6340 ecs
->event_thread
->initiating_frame
))
6342 /* Case 2. Fall through. */
6352 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6354 delete_step_resume_breakpoint (ecs
->event_thread
);
6356 end_stepping_range (ecs
);
6360 case BPSTAT_WHAT_SINGLE
:
6362 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6363 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6364 /* Still need to check other stuff, at least the case where we
6365 are stepping and step out of the right range. */
6368 case BPSTAT_WHAT_STEP_RESUME
:
6370 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6372 delete_step_resume_breakpoint (ecs
->event_thread
);
6373 if (ecs
->event_thread
->control
.proceed_to_finish
6374 && execution_direction
== EXEC_REVERSE
)
6376 struct thread_info
*tp
= ecs
->event_thread
;
6378 /* We are finishing a function in reverse, and just hit the
6379 step-resume breakpoint at the start address of the
6380 function, and we're almost there -- just need to back up
6381 by one more single-step, which should take us back to the
6383 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6387 fill_in_stop_func (gdbarch
, ecs
);
6388 if (stop_pc
== ecs
->stop_func_start
6389 && execution_direction
== EXEC_REVERSE
)
6391 /* We are stepping over a function call in reverse, and just
6392 hit the step-resume breakpoint at the start address of
6393 the function. Go back to single-stepping, which should
6394 take us back to the function call. */
6395 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6401 case BPSTAT_WHAT_STOP_NOISY
:
6403 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6404 stop_print_frame
= 1;
6406 /* Assume the thread stopped for a breapoint. We'll still check
6407 whether a/the breakpoint is there when the thread is next
6409 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6414 case BPSTAT_WHAT_STOP_SILENT
:
6416 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6417 stop_print_frame
= 0;
6419 /* Assume the thread stopped for a breapoint. We'll still check
6420 whether a/the breakpoint is there when the thread is next
6422 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6426 case BPSTAT_WHAT_HP_STEP_RESUME
:
6428 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6430 delete_step_resume_breakpoint (ecs
->event_thread
);
6431 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6433 /* Back when the step-resume breakpoint was inserted, we
6434 were trying to single-step off a breakpoint. Go back to
6436 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6437 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6443 case BPSTAT_WHAT_KEEP_CHECKING
:
6447 /* If we stepped a permanent breakpoint and we had a high priority
6448 step-resume breakpoint for the address we stepped, but we didn't
6449 hit it, then we must have stepped into the signal handler. The
6450 step-resume was only necessary to catch the case of _not_
6451 stepping into the handler, so delete it, and fall through to
6452 checking whether the step finished. */
6453 if (ecs
->event_thread
->stepped_breakpoint
)
6455 struct breakpoint
*sr_bp
6456 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6459 && sr_bp
->loc
->permanent
6460 && sr_bp
->type
== bp_hp_step_resume
6461 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6464 fprintf_unfiltered (gdb_stdlog
,
6465 "infrun: stepped permanent breakpoint, stopped in "
6467 delete_step_resume_breakpoint (ecs
->event_thread
);
6468 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6472 /* We come here if we hit a breakpoint but should not stop for it.
6473 Possibly we also were stepping and should stop for that. So fall
6474 through and test for stepping. But, if not stepping, do not
6477 /* In all-stop mode, if we're currently stepping but have stopped in
6478 some other thread, we need to switch back to the stepped thread. */
6479 if (switch_back_to_stepped_thread (ecs
))
6482 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6485 fprintf_unfiltered (gdb_stdlog
,
6486 "infrun: step-resume breakpoint is inserted\n");
6488 /* Having a step-resume breakpoint overrides anything
6489 else having to do with stepping commands until
6490 that breakpoint is reached. */
6495 if (ecs
->event_thread
->control
.step_range_end
== 0)
6498 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6499 /* Likewise if we aren't even stepping. */
6504 /* Re-fetch current thread's frame in case the code above caused
6505 the frame cache to be re-initialized, making our FRAME variable
6506 a dangling pointer. */
6507 frame
= get_current_frame ();
6508 gdbarch
= get_frame_arch (frame
);
6509 fill_in_stop_func (gdbarch
, ecs
);
6511 /* If stepping through a line, keep going if still within it.
6513 Note that step_range_end is the address of the first instruction
6514 beyond the step range, and NOT the address of the last instruction
6517 Note also that during reverse execution, we may be stepping
6518 through a function epilogue and therefore must detect when
6519 the current-frame changes in the middle of a line. */
6521 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6522 && (execution_direction
!= EXEC_REVERSE
6523 || frame_id_eq (get_frame_id (frame
),
6524 ecs
->event_thread
->control
.step_frame_id
)))
6528 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6529 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6530 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6532 /* Tentatively re-enable range stepping; `resume' disables it if
6533 necessary (e.g., if we're stepping over a breakpoint or we
6534 have software watchpoints). */
6535 ecs
->event_thread
->control
.may_range_step
= 1;
6537 /* When stepping backward, stop at beginning of line range
6538 (unless it's the function entry point, in which case
6539 keep going back to the call point). */
6540 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6541 && stop_pc
!= ecs
->stop_func_start
6542 && execution_direction
== EXEC_REVERSE
)
6543 end_stepping_range (ecs
);
6550 /* We stepped out of the stepping range. */
6552 /* If we are stepping at the source level and entered the runtime
6553 loader dynamic symbol resolution code...
6555 EXEC_FORWARD: we keep on single stepping until we exit the run
6556 time loader code and reach the callee's address.
6558 EXEC_REVERSE: we've already executed the callee (backward), and
6559 the runtime loader code is handled just like any other
6560 undebuggable function call. Now we need only keep stepping
6561 backward through the trampoline code, and that's handled further
6562 down, so there is nothing for us to do here. */
6564 if (execution_direction
!= EXEC_REVERSE
6565 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6566 && in_solib_dynsym_resolve_code (stop_pc
))
6568 CORE_ADDR pc_after_resolver
=
6569 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6572 fprintf_unfiltered (gdb_stdlog
,
6573 "infrun: stepped into dynsym resolve code\n");
6575 if (pc_after_resolver
)
6577 /* Set up a step-resume breakpoint at the address
6578 indicated by SKIP_SOLIB_RESOLVER. */
6579 struct symtab_and_line sr_sal
;
6582 sr_sal
.pc
= pc_after_resolver
;
6583 sr_sal
.pspace
= get_frame_program_space (frame
);
6585 insert_step_resume_breakpoint_at_sal (gdbarch
,
6586 sr_sal
, null_frame_id
);
6593 if (ecs
->event_thread
->control
.step_range_end
!= 1
6594 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6595 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6596 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6599 fprintf_unfiltered (gdb_stdlog
,
6600 "infrun: stepped into signal trampoline\n");
6601 /* The inferior, while doing a "step" or "next", has ended up in
6602 a signal trampoline (either by a signal being delivered or by
6603 the signal handler returning). Just single-step until the
6604 inferior leaves the trampoline (either by calling the handler
6610 /* If we're in the return path from a shared library trampoline,
6611 we want to proceed through the trampoline when stepping. */
6612 /* macro/2012-04-25: This needs to come before the subroutine
6613 call check below as on some targets return trampolines look
6614 like subroutine calls (MIPS16 return thunks). */
6615 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6616 stop_pc
, ecs
->stop_func_name
)
6617 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6619 /* Determine where this trampoline returns. */
6620 CORE_ADDR real_stop_pc
;
6622 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6625 fprintf_unfiltered (gdb_stdlog
,
6626 "infrun: stepped into solib return tramp\n");
6628 /* Only proceed through if we know where it's going. */
6631 /* And put the step-breakpoint there and go until there. */
6632 struct symtab_and_line sr_sal
;
6634 init_sal (&sr_sal
); /* initialize to zeroes */
6635 sr_sal
.pc
= real_stop_pc
;
6636 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6637 sr_sal
.pspace
= get_frame_program_space (frame
);
6639 /* Do not specify what the fp should be when we stop since
6640 on some machines the prologue is where the new fp value
6642 insert_step_resume_breakpoint_at_sal (gdbarch
,
6643 sr_sal
, null_frame_id
);
6645 /* Restart without fiddling with the step ranges or
6652 /* Check for subroutine calls. The check for the current frame
6653 equalling the step ID is not necessary - the check of the
6654 previous frame's ID is sufficient - but it is a common case and
6655 cheaper than checking the previous frame's ID.
6657 NOTE: frame_id_eq will never report two invalid frame IDs as
6658 being equal, so to get into this block, both the current and
6659 previous frame must have valid frame IDs. */
6660 /* The outer_frame_id check is a heuristic to detect stepping
6661 through startup code. If we step over an instruction which
6662 sets the stack pointer from an invalid value to a valid value,
6663 we may detect that as a subroutine call from the mythical
6664 "outermost" function. This could be fixed by marking
6665 outermost frames as !stack_p,code_p,special_p. Then the
6666 initial outermost frame, before sp was valid, would
6667 have code_addr == &_start. See the comment in frame_id_eq
6669 if (!frame_id_eq (get_stack_frame_id (frame
),
6670 ecs
->event_thread
->control
.step_stack_frame_id
)
6671 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6672 ecs
->event_thread
->control
.step_stack_frame_id
)
6673 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6675 || (ecs
->event_thread
->control
.step_start_function
6676 != find_pc_function (stop_pc
)))))
6678 CORE_ADDR real_stop_pc
;
6681 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6683 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6685 /* I presume that step_over_calls is only 0 when we're
6686 supposed to be stepping at the assembly language level
6687 ("stepi"). Just stop. */
6688 /* And this works the same backward as frontward. MVS */
6689 end_stepping_range (ecs
);
6693 /* Reverse stepping through solib trampolines. */
6695 if (execution_direction
== EXEC_REVERSE
6696 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6697 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6698 || (ecs
->stop_func_start
== 0
6699 && in_solib_dynsym_resolve_code (stop_pc
))))
6701 /* Any solib trampoline code can be handled in reverse
6702 by simply continuing to single-step. We have already
6703 executed the solib function (backwards), and a few
6704 steps will take us back through the trampoline to the
6710 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6712 /* We're doing a "next".
6714 Normal (forward) execution: set a breakpoint at the
6715 callee's return address (the address at which the caller
6718 Reverse (backward) execution. set the step-resume
6719 breakpoint at the start of the function that we just
6720 stepped into (backwards), and continue to there. When we
6721 get there, we'll need to single-step back to the caller. */
6723 if (execution_direction
== EXEC_REVERSE
)
6725 /* If we're already at the start of the function, we've either
6726 just stepped backward into a single instruction function,
6727 or stepped back out of a signal handler to the first instruction
6728 of the function. Just keep going, which will single-step back
6730 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6732 struct symtab_and_line sr_sal
;
6734 /* Normal function call return (static or dynamic). */
6736 sr_sal
.pc
= ecs
->stop_func_start
;
6737 sr_sal
.pspace
= get_frame_program_space (frame
);
6738 insert_step_resume_breakpoint_at_sal (gdbarch
,
6739 sr_sal
, null_frame_id
);
6743 insert_step_resume_breakpoint_at_caller (frame
);
6749 /* If we are in a function call trampoline (a stub between the
6750 calling routine and the real function), locate the real
6751 function. That's what tells us (a) whether we want to step
6752 into it at all, and (b) what prologue we want to run to the
6753 end of, if we do step into it. */
6754 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6755 if (real_stop_pc
== 0)
6756 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6757 if (real_stop_pc
!= 0)
6758 ecs
->stop_func_start
= real_stop_pc
;
6760 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6762 struct symtab_and_line sr_sal
;
6765 sr_sal
.pc
= ecs
->stop_func_start
;
6766 sr_sal
.pspace
= get_frame_program_space (frame
);
6768 insert_step_resume_breakpoint_at_sal (gdbarch
,
6769 sr_sal
, null_frame_id
);
6774 /* If we have line number information for the function we are
6775 thinking of stepping into and the function isn't on the skip
6778 If there are several symtabs at that PC (e.g. with include
6779 files), just want to know whether *any* of them have line
6780 numbers. find_pc_line handles this. */
6782 struct symtab_and_line tmp_sal
;
6784 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6785 if (tmp_sal
.line
!= 0
6786 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6789 if (execution_direction
== EXEC_REVERSE
)
6790 handle_step_into_function_backward (gdbarch
, ecs
);
6792 handle_step_into_function (gdbarch
, ecs
);
6797 /* If we have no line number and the step-stop-if-no-debug is
6798 set, we stop the step so that the user has a chance to switch
6799 in assembly mode. */
6800 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6801 && step_stop_if_no_debug
)
6803 end_stepping_range (ecs
);
6807 if (execution_direction
== EXEC_REVERSE
)
6809 /* If we're already at the start of the function, we've either just
6810 stepped backward into a single instruction function without line
6811 number info, or stepped back out of a signal handler to the first
6812 instruction of the function without line number info. Just keep
6813 going, which will single-step back to the caller. */
6814 if (ecs
->stop_func_start
!= stop_pc
)
6816 /* Set a breakpoint at callee's start address.
6817 From there we can step once and be back in the caller. */
6818 struct symtab_and_line sr_sal
;
6821 sr_sal
.pc
= ecs
->stop_func_start
;
6822 sr_sal
.pspace
= get_frame_program_space (frame
);
6823 insert_step_resume_breakpoint_at_sal (gdbarch
,
6824 sr_sal
, null_frame_id
);
6828 /* Set a breakpoint at callee's return address (the address
6829 at which the caller will resume). */
6830 insert_step_resume_breakpoint_at_caller (frame
);
6836 /* Reverse stepping through solib trampolines. */
6838 if (execution_direction
== EXEC_REVERSE
6839 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6841 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6842 || (ecs
->stop_func_start
== 0
6843 && in_solib_dynsym_resolve_code (stop_pc
)))
6845 /* Any solib trampoline code can be handled in reverse
6846 by simply continuing to single-step. We have already
6847 executed the solib function (backwards), and a few
6848 steps will take us back through the trampoline to the
6853 else if (in_solib_dynsym_resolve_code (stop_pc
))
6855 /* Stepped backward into the solib dynsym resolver.
6856 Set a breakpoint at its start and continue, then
6857 one more step will take us out. */
6858 struct symtab_and_line sr_sal
;
6861 sr_sal
.pc
= ecs
->stop_func_start
;
6862 sr_sal
.pspace
= get_frame_program_space (frame
);
6863 insert_step_resume_breakpoint_at_sal (gdbarch
,
6864 sr_sal
, null_frame_id
);
6870 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6872 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6873 the trampoline processing logic, however, there are some trampolines
6874 that have no names, so we should do trampoline handling first. */
6875 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6876 && ecs
->stop_func_name
== NULL
6877 && stop_pc_sal
.line
== 0)
6880 fprintf_unfiltered (gdb_stdlog
,
6881 "infrun: stepped into undebuggable function\n");
6883 /* The inferior just stepped into, or returned to, an
6884 undebuggable function (where there is no debugging information
6885 and no line number corresponding to the address where the
6886 inferior stopped). Since we want to skip this kind of code,
6887 we keep going until the inferior returns from this
6888 function - unless the user has asked us not to (via
6889 set step-mode) or we no longer know how to get back
6890 to the call site. */
6891 if (step_stop_if_no_debug
6892 || !frame_id_p (frame_unwind_caller_id (frame
)))
6894 /* If we have no line number and the step-stop-if-no-debug
6895 is set, we stop the step so that the user has a chance to
6896 switch in assembly mode. */
6897 end_stepping_range (ecs
);
6902 /* Set a breakpoint at callee's return address (the address
6903 at which the caller will resume). */
6904 insert_step_resume_breakpoint_at_caller (frame
);
6910 if (ecs
->event_thread
->control
.step_range_end
== 1)
6912 /* It is stepi or nexti. We always want to stop stepping after
6915 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6916 end_stepping_range (ecs
);
6920 if (stop_pc_sal
.line
== 0)
6922 /* We have no line number information. That means to stop
6923 stepping (does this always happen right after one instruction,
6924 when we do "s" in a function with no line numbers,
6925 or can this happen as a result of a return or longjmp?). */
6927 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6928 end_stepping_range (ecs
);
6932 /* Look for "calls" to inlined functions, part one. If the inline
6933 frame machinery detected some skipped call sites, we have entered
6934 a new inline function. */
6936 if (frame_id_eq (get_frame_id (get_current_frame ()),
6937 ecs
->event_thread
->control
.step_frame_id
)
6938 && inline_skipped_frames (ecs
->ptid
))
6940 struct symtab_and_line call_sal
;
6943 fprintf_unfiltered (gdb_stdlog
,
6944 "infrun: stepped into inlined function\n");
6946 find_frame_sal (get_current_frame (), &call_sal
);
6948 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6950 /* For "step", we're going to stop. But if the call site
6951 for this inlined function is on the same source line as
6952 we were previously stepping, go down into the function
6953 first. Otherwise stop at the call site. */
6955 if (call_sal
.line
== ecs
->event_thread
->current_line
6956 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6957 step_into_inline_frame (ecs
->ptid
);
6959 end_stepping_range (ecs
);
6964 /* For "next", we should stop at the call site if it is on a
6965 different source line. Otherwise continue through the
6966 inlined function. */
6967 if (call_sal
.line
== ecs
->event_thread
->current_line
6968 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6971 end_stepping_range (ecs
);
6976 /* Look for "calls" to inlined functions, part two. If we are still
6977 in the same real function we were stepping through, but we have
6978 to go further up to find the exact frame ID, we are stepping
6979 through a more inlined call beyond its call site. */
6981 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6982 && !frame_id_eq (get_frame_id (get_current_frame ()),
6983 ecs
->event_thread
->control
.step_frame_id
)
6984 && stepped_in_from (get_current_frame (),
6985 ecs
->event_thread
->control
.step_frame_id
))
6988 fprintf_unfiltered (gdb_stdlog
,
6989 "infrun: stepping through inlined function\n");
6991 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6994 end_stepping_range (ecs
);
6998 if ((stop_pc
== stop_pc_sal
.pc
)
6999 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
7000 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
7002 /* We are at the start of a different line. So stop. Note that
7003 we don't stop if we step into the middle of a different line.
7004 That is said to make things like for (;;) statements work
7007 fprintf_unfiltered (gdb_stdlog
,
7008 "infrun: stepped to a different line\n");
7009 end_stepping_range (ecs
);
7013 /* We aren't done stepping.
7015 Optimize by setting the stepping range to the line.
7016 (We might not be in the original line, but if we entered a
7017 new line in mid-statement, we continue stepping. This makes
7018 things like for(;;) statements work better.) */
7020 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7021 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7022 ecs
->event_thread
->control
.may_range_step
= 1;
7023 set_step_info (frame
, stop_pc_sal
);
7026 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
7030 /* In all-stop mode, if we're currently stepping but have stopped in
7031 some other thread, we may need to switch back to the stepped
7032 thread. Returns true we set the inferior running, false if we left
7033 it stopped (and the event needs further processing). */
7036 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7038 if (!target_is_non_stop_p ())
7040 struct thread_info
*tp
;
7041 struct thread_info
*stepping_thread
;
7043 /* If any thread is blocked on some internal breakpoint, and we
7044 simply need to step over that breakpoint to get it going
7045 again, do that first. */
7047 /* However, if we see an event for the stepping thread, then we
7048 know all other threads have been moved past their breakpoints
7049 already. Let the caller check whether the step is finished,
7050 etc., before deciding to move it past a breakpoint. */
7051 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7054 /* Check if the current thread is blocked on an incomplete
7055 step-over, interrupted by a random signal. */
7056 if (ecs
->event_thread
->control
.trap_expected
7057 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7061 fprintf_unfiltered (gdb_stdlog
,
7062 "infrun: need to finish step-over of [%s]\n",
7063 target_pid_to_str (ecs
->event_thread
->ptid
));
7069 /* Check if the current thread is blocked by a single-step
7070 breakpoint of another thread. */
7071 if (ecs
->hit_singlestep_breakpoint
)
7075 fprintf_unfiltered (gdb_stdlog
,
7076 "infrun: need to step [%s] over single-step "
7078 target_pid_to_str (ecs
->ptid
));
7084 /* If this thread needs yet another step-over (e.g., stepping
7085 through a delay slot), do it first before moving on to
7087 if (thread_still_needs_step_over (ecs
->event_thread
))
7091 fprintf_unfiltered (gdb_stdlog
,
7092 "infrun: thread [%s] still needs step-over\n",
7093 target_pid_to_str (ecs
->event_thread
->ptid
));
7099 /* If scheduler locking applies even if not stepping, there's no
7100 need to walk over threads. Above we've checked whether the
7101 current thread is stepping. If some other thread not the
7102 event thread is stepping, then it must be that scheduler
7103 locking is not in effect. */
7104 if (schedlock_applies (ecs
->event_thread
))
7107 /* Otherwise, we no longer expect a trap in the current thread.
7108 Clear the trap_expected flag before switching back -- this is
7109 what keep_going does as well, if we call it. */
7110 ecs
->event_thread
->control
.trap_expected
= 0;
7112 /* Likewise, clear the signal if it should not be passed. */
7113 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7114 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7116 /* Do all pending step-overs before actually proceeding with
7118 if (start_step_over ())
7120 prepare_to_wait (ecs
);
7124 /* Look for the stepping/nexting thread. */
7125 stepping_thread
= NULL
;
7127 ALL_NON_EXITED_THREADS (tp
)
7129 /* Ignore threads of processes the caller is not
7132 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
7135 /* When stepping over a breakpoint, we lock all threads
7136 except the one that needs to move past the breakpoint.
7137 If a non-event thread has this set, the "incomplete
7138 step-over" check above should have caught it earlier. */
7139 if (tp
->control
.trap_expected
)
7141 internal_error (__FILE__
, __LINE__
,
7142 "[%s] has inconsistent state: "
7143 "trap_expected=%d\n",
7144 target_pid_to_str (tp
->ptid
),
7145 tp
->control
.trap_expected
);
7148 /* Did we find the stepping thread? */
7149 if (tp
->control
.step_range_end
)
7151 /* Yep. There should only one though. */
7152 gdb_assert (stepping_thread
== NULL
);
7154 /* The event thread is handled at the top, before we
7156 gdb_assert (tp
!= ecs
->event_thread
);
7158 /* If some thread other than the event thread is
7159 stepping, then scheduler locking can't be in effect,
7160 otherwise we wouldn't have resumed the current event
7161 thread in the first place. */
7162 gdb_assert (!schedlock_applies (tp
));
7164 stepping_thread
= tp
;
7168 if (stepping_thread
!= NULL
)
7171 fprintf_unfiltered (gdb_stdlog
,
7172 "infrun: switching back to stepped thread\n");
7174 if (keep_going_stepped_thread (stepping_thread
))
7176 prepare_to_wait (ecs
);
7185 /* Set a previously stepped thread back to stepping. Returns true on
7186 success, false if the resume is not possible (e.g., the thread
7190 keep_going_stepped_thread (struct thread_info
*tp
)
7192 struct frame_info
*frame
;
7193 struct execution_control_state ecss
;
7194 struct execution_control_state
*ecs
= &ecss
;
7196 /* If the stepping thread exited, then don't try to switch back and
7197 resume it, which could fail in several different ways depending
7198 on the target. Instead, just keep going.
7200 We can find a stepping dead thread in the thread list in two
7203 - The target supports thread exit events, and when the target
7204 tries to delete the thread from the thread list, inferior_ptid
7205 pointed at the exiting thread. In such case, calling
7206 delete_thread does not really remove the thread from the list;
7207 instead, the thread is left listed, with 'exited' state.
7209 - The target's debug interface does not support thread exit
7210 events, and so we have no idea whatsoever if the previously
7211 stepping thread is still alive. For that reason, we need to
7212 synchronously query the target now. */
7214 if (is_exited (tp
->ptid
)
7215 || !target_thread_alive (tp
->ptid
))
7218 fprintf_unfiltered (gdb_stdlog
,
7219 "infrun: not resuming previously "
7220 "stepped thread, it has vanished\n");
7222 delete_thread (tp
->ptid
);
7227 fprintf_unfiltered (gdb_stdlog
,
7228 "infrun: resuming previously stepped thread\n");
7230 reset_ecs (ecs
, tp
);
7231 switch_to_thread (tp
->ptid
);
7233 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
7234 frame
= get_current_frame ();
7236 /* If the PC of the thread we were trying to single-step has
7237 changed, then that thread has trapped or been signaled, but the
7238 event has not been reported to GDB yet. Re-poll the target
7239 looking for this particular thread's event (i.e. temporarily
7240 enable schedlock) by:
7242 - setting a break at the current PC
7243 - resuming that particular thread, only (by setting trap
7246 This prevents us continuously moving the single-step breakpoint
7247 forward, one instruction at a time, overstepping. */
7249 if (stop_pc
!= tp
->prev_pc
)
7254 fprintf_unfiltered (gdb_stdlog
,
7255 "infrun: expected thread advanced also (%s -> %s)\n",
7256 paddress (target_gdbarch (), tp
->prev_pc
),
7257 paddress (target_gdbarch (), stop_pc
));
7259 /* Clear the info of the previous step-over, as it's no longer
7260 valid (if the thread was trying to step over a breakpoint, it
7261 has already succeeded). It's what keep_going would do too,
7262 if we called it. Do this before trying to insert the sss
7263 breakpoint, otherwise if we were previously trying to step
7264 over this exact address in another thread, the breakpoint is
7266 clear_step_over_info ();
7267 tp
->control
.trap_expected
= 0;
7269 insert_single_step_breakpoint (get_frame_arch (frame
),
7270 get_frame_address_space (frame
),
7274 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7275 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7280 fprintf_unfiltered (gdb_stdlog
,
7281 "infrun: expected thread still hasn't advanced\n");
7283 keep_going_pass_signal (ecs
);
7288 /* Is thread TP in the middle of (software or hardware)
7289 single-stepping? (Note the result of this function must never be
7290 passed directly as target_resume's STEP parameter.) */
7293 currently_stepping (struct thread_info
*tp
)
7295 return ((tp
->control
.step_range_end
7296 && tp
->control
.step_resume_breakpoint
== NULL
)
7297 || tp
->control
.trap_expected
7298 || tp
->stepped_breakpoint
7299 || bpstat_should_step ());
7302 /* Inferior has stepped into a subroutine call with source code that
7303 we should not step over. Do step to the first line of code in
7307 handle_step_into_function (struct gdbarch
*gdbarch
,
7308 struct execution_control_state
*ecs
)
7310 struct compunit_symtab
*cust
;
7311 struct symtab_and_line stop_func_sal
, sr_sal
;
7313 fill_in_stop_func (gdbarch
, ecs
);
7315 cust
= find_pc_compunit_symtab (stop_pc
);
7316 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7317 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7318 ecs
->stop_func_start
);
7320 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7321 /* Use the step_resume_break to step until the end of the prologue,
7322 even if that involves jumps (as it seems to on the vax under
7324 /* If the prologue ends in the middle of a source line, continue to
7325 the end of that source line (if it is still within the function).
7326 Otherwise, just go to end of prologue. */
7327 if (stop_func_sal
.end
7328 && stop_func_sal
.pc
!= ecs
->stop_func_start
7329 && stop_func_sal
.end
< ecs
->stop_func_end
)
7330 ecs
->stop_func_start
= stop_func_sal
.end
;
7332 /* Architectures which require breakpoint adjustment might not be able
7333 to place a breakpoint at the computed address. If so, the test
7334 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7335 ecs->stop_func_start to an address at which a breakpoint may be
7336 legitimately placed.
7338 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7339 made, GDB will enter an infinite loop when stepping through
7340 optimized code consisting of VLIW instructions which contain
7341 subinstructions corresponding to different source lines. On
7342 FR-V, it's not permitted to place a breakpoint on any but the
7343 first subinstruction of a VLIW instruction. When a breakpoint is
7344 set, GDB will adjust the breakpoint address to the beginning of
7345 the VLIW instruction. Thus, we need to make the corresponding
7346 adjustment here when computing the stop address. */
7348 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7350 ecs
->stop_func_start
7351 = gdbarch_adjust_breakpoint_address (gdbarch
,
7352 ecs
->stop_func_start
);
7355 if (ecs
->stop_func_start
== stop_pc
)
7357 /* We are already there: stop now. */
7358 end_stepping_range (ecs
);
7363 /* Put the step-breakpoint there and go until there. */
7364 init_sal (&sr_sal
); /* initialize to zeroes */
7365 sr_sal
.pc
= ecs
->stop_func_start
;
7366 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7367 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7369 /* Do not specify what the fp should be when we stop since on
7370 some machines the prologue is where the new fp value is
7372 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7374 /* And make sure stepping stops right away then. */
7375 ecs
->event_thread
->control
.step_range_end
7376 = ecs
->event_thread
->control
.step_range_start
;
7381 /* Inferior has stepped backward into a subroutine call with source
7382 code that we should not step over. Do step to the beginning of the
7383 last line of code in it. */
7386 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7387 struct execution_control_state
*ecs
)
7389 struct compunit_symtab
*cust
;
7390 struct symtab_and_line stop_func_sal
;
7392 fill_in_stop_func (gdbarch
, ecs
);
7394 cust
= find_pc_compunit_symtab (stop_pc
);
7395 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7396 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7397 ecs
->stop_func_start
);
7399 stop_func_sal
= find_pc_line (stop_pc
, 0);
7401 /* OK, we're just going to keep stepping here. */
7402 if (stop_func_sal
.pc
== stop_pc
)
7404 /* We're there already. Just stop stepping now. */
7405 end_stepping_range (ecs
);
7409 /* Else just reset the step range and keep going.
7410 No step-resume breakpoint, they don't work for
7411 epilogues, which can have multiple entry paths. */
7412 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7413 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7419 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7420 This is used to both functions and to skip over code. */
7423 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7424 struct symtab_and_line sr_sal
,
7425 struct frame_id sr_id
,
7426 enum bptype sr_type
)
7428 /* There should never be more than one step-resume or longjmp-resume
7429 breakpoint per thread, so we should never be setting a new
7430 step_resume_breakpoint when one is already active. */
7431 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7432 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7435 fprintf_unfiltered (gdb_stdlog
,
7436 "infrun: inserting step-resume breakpoint at %s\n",
7437 paddress (gdbarch
, sr_sal
.pc
));
7439 inferior_thread ()->control
.step_resume_breakpoint
7440 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
7444 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7445 struct symtab_and_line sr_sal
,
7446 struct frame_id sr_id
)
7448 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7453 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7454 This is used to skip a potential signal handler.
7456 This is called with the interrupted function's frame. The signal
7457 handler, when it returns, will resume the interrupted function at
7461 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7463 struct symtab_and_line sr_sal
;
7464 struct gdbarch
*gdbarch
;
7466 gdb_assert (return_frame
!= NULL
);
7467 init_sal (&sr_sal
); /* initialize to zeros */
7469 gdbarch
= get_frame_arch (return_frame
);
7470 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7471 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7472 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7474 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7475 get_stack_frame_id (return_frame
),
7479 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7480 is used to skip a function after stepping into it (for "next" or if
7481 the called function has no debugging information).
7483 The current function has almost always been reached by single
7484 stepping a call or return instruction. NEXT_FRAME belongs to the
7485 current function, and the breakpoint will be set at the caller's
7488 This is a separate function rather than reusing
7489 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7490 get_prev_frame, which may stop prematurely (see the implementation
7491 of frame_unwind_caller_id for an example). */
7494 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7496 struct symtab_and_line sr_sal
;
7497 struct gdbarch
*gdbarch
;
7499 /* We shouldn't have gotten here if we don't know where the call site
7501 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7503 init_sal (&sr_sal
); /* initialize to zeros */
7505 gdbarch
= frame_unwind_caller_arch (next_frame
);
7506 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7507 frame_unwind_caller_pc (next_frame
));
7508 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7509 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7511 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7512 frame_unwind_caller_id (next_frame
));
7515 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7516 new breakpoint at the target of a jmp_buf. The handling of
7517 longjmp-resume uses the same mechanisms used for handling
7518 "step-resume" breakpoints. */
7521 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7523 /* There should never be more than one longjmp-resume breakpoint per
7524 thread, so we should never be setting a new
7525 longjmp_resume_breakpoint when one is already active. */
7526 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7529 fprintf_unfiltered (gdb_stdlog
,
7530 "infrun: inserting longjmp-resume breakpoint at %s\n",
7531 paddress (gdbarch
, pc
));
7533 inferior_thread ()->control
.exception_resume_breakpoint
=
7534 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
7537 /* Insert an exception resume breakpoint. TP is the thread throwing
7538 the exception. The block B is the block of the unwinder debug hook
7539 function. FRAME is the frame corresponding to the call to this
7540 function. SYM is the symbol of the function argument holding the
7541 target PC of the exception. */
7544 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7545 const struct block
*b
,
7546 struct frame_info
*frame
,
7551 struct block_symbol vsym
;
7552 struct value
*value
;
7554 struct breakpoint
*bp
;
7556 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
7557 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7558 /* If the value was optimized out, revert to the old behavior. */
7559 if (! value_optimized_out (value
))
7561 handler
= value_as_address (value
);
7564 fprintf_unfiltered (gdb_stdlog
,
7565 "infrun: exception resume at %lx\n",
7566 (unsigned long) handler
);
7568 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7569 handler
, bp_exception_resume
);
7571 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7574 bp
->thread
= tp
->global_num
;
7575 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7578 CATCH (e
, RETURN_MASK_ERROR
)
7580 /* We want to ignore errors here. */
7585 /* A helper for check_exception_resume that sets an
7586 exception-breakpoint based on a SystemTap probe. */
7589 insert_exception_resume_from_probe (struct thread_info
*tp
,
7590 const struct bound_probe
*probe
,
7591 struct frame_info
*frame
)
7593 struct value
*arg_value
;
7595 struct breakpoint
*bp
;
7597 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7601 handler
= value_as_address (arg_value
);
7604 fprintf_unfiltered (gdb_stdlog
,
7605 "infrun: exception resume at %s\n",
7606 paddress (get_objfile_arch (probe
->objfile
),
7609 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7610 handler
, bp_exception_resume
);
7611 bp
->thread
= tp
->global_num
;
7612 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7615 /* This is called when an exception has been intercepted. Check to
7616 see whether the exception's destination is of interest, and if so,
7617 set an exception resume breakpoint there. */
7620 check_exception_resume (struct execution_control_state
*ecs
,
7621 struct frame_info
*frame
)
7623 struct bound_probe probe
;
7624 struct symbol
*func
;
7626 /* First see if this exception unwinding breakpoint was set via a
7627 SystemTap probe point. If so, the probe has two arguments: the
7628 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7629 set a breakpoint there. */
7630 probe
= find_probe_by_pc (get_frame_pc (frame
));
7633 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7637 func
= get_frame_function (frame
);
7643 const struct block
*b
;
7644 struct block_iterator iter
;
7648 /* The exception breakpoint is a thread-specific breakpoint on
7649 the unwinder's debug hook, declared as:
7651 void _Unwind_DebugHook (void *cfa, void *handler);
7653 The CFA argument indicates the frame to which control is
7654 about to be transferred. HANDLER is the destination PC.
7656 We ignore the CFA and set a temporary breakpoint at HANDLER.
7657 This is not extremely efficient but it avoids issues in gdb
7658 with computing the DWARF CFA, and it also works even in weird
7659 cases such as throwing an exception from inside a signal
7662 b
= SYMBOL_BLOCK_VALUE (func
);
7663 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7665 if (!SYMBOL_IS_ARGUMENT (sym
))
7672 insert_exception_resume_breakpoint (ecs
->event_thread
,
7678 CATCH (e
, RETURN_MASK_ERROR
)
7685 stop_waiting (struct execution_control_state
*ecs
)
7688 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7690 /* Let callers know we don't want to wait for the inferior anymore. */
7691 ecs
->wait_some_more
= 0;
7693 /* If all-stop, but the target is always in non-stop mode, stop all
7694 threads now that we're presenting the stop to the user. */
7695 if (!non_stop
&& target_is_non_stop_p ())
7696 stop_all_threads ();
7699 /* Like keep_going, but passes the signal to the inferior, even if the
7700 signal is set to nopass. */
7703 keep_going_pass_signal (struct execution_control_state
*ecs
)
7705 /* Make sure normal_stop is called if we get a QUIT handled before
7707 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
7709 gdb_assert (ptid_equal (ecs
->event_thread
->ptid
, inferior_ptid
));
7710 gdb_assert (!ecs
->event_thread
->resumed
);
7712 /* Save the pc before execution, to compare with pc after stop. */
7713 ecs
->event_thread
->prev_pc
7714 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
7716 if (ecs
->event_thread
->control
.trap_expected
)
7718 struct thread_info
*tp
= ecs
->event_thread
;
7721 fprintf_unfiltered (gdb_stdlog
,
7722 "infrun: %s has trap_expected set, "
7723 "resuming to collect trap\n",
7724 target_pid_to_str (tp
->ptid
));
7726 /* We haven't yet gotten our trap, and either: intercepted a
7727 non-signal event (e.g., a fork); or took a signal which we
7728 are supposed to pass through to the inferior. Simply
7730 discard_cleanups (old_cleanups
);
7731 resume (ecs
->event_thread
->suspend
.stop_signal
);
7733 else if (step_over_info_valid_p ())
7735 /* Another thread is stepping over a breakpoint in-line. If
7736 this thread needs a step-over too, queue the request. In
7737 either case, this resume must be deferred for later. */
7738 struct thread_info
*tp
= ecs
->event_thread
;
7740 if (ecs
->hit_singlestep_breakpoint
7741 || thread_still_needs_step_over (tp
))
7744 fprintf_unfiltered (gdb_stdlog
,
7745 "infrun: step-over already in progress: "
7746 "step-over for %s deferred\n",
7747 target_pid_to_str (tp
->ptid
));
7748 thread_step_over_chain_enqueue (tp
);
7753 fprintf_unfiltered (gdb_stdlog
,
7754 "infrun: step-over in progress: "
7755 "resume of %s deferred\n",
7756 target_pid_to_str (tp
->ptid
));
7759 discard_cleanups (old_cleanups
);
7763 struct regcache
*regcache
= get_current_regcache ();
7766 step_over_what step_what
;
7768 /* Either the trap was not expected, but we are continuing
7769 anyway (if we got a signal, the user asked it be passed to
7772 We got our expected trap, but decided we should resume from
7775 We're going to run this baby now!
7777 Note that insert_breakpoints won't try to re-insert
7778 already inserted breakpoints. Therefore, we don't
7779 care if breakpoints were already inserted, or not. */
7781 /* If we need to step over a breakpoint, and we're not using
7782 displaced stepping to do so, insert all breakpoints
7783 (watchpoints, etc.) but the one we're stepping over, step one
7784 instruction, and then re-insert the breakpoint when that step
7787 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7789 remove_bp
= (ecs
->hit_singlestep_breakpoint
7790 || (step_what
& STEP_OVER_BREAKPOINT
));
7791 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7793 /* We can't use displaced stepping if we need to step past a
7794 watchpoint. The instruction copied to the scratch pad would
7795 still trigger the watchpoint. */
7797 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7799 set_step_over_info (get_regcache_aspace (regcache
),
7800 regcache_read_pc (regcache
), remove_wps
,
7801 ecs
->event_thread
->global_num
);
7803 else if (remove_wps
)
7804 set_step_over_info (NULL
, 0, remove_wps
, -1);
7806 /* If we now need to do an in-line step-over, we need to stop
7807 all other threads. Note this must be done before
7808 insert_breakpoints below, because that removes the breakpoint
7809 we're about to step over, otherwise other threads could miss
7811 if (step_over_info_valid_p () && target_is_non_stop_p ())
7812 stop_all_threads ();
7814 /* Stop stepping if inserting breakpoints fails. */
7817 insert_breakpoints ();
7819 CATCH (e
, RETURN_MASK_ERROR
)
7821 exception_print (gdb_stderr
, e
);
7823 discard_cleanups (old_cleanups
);
7828 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7830 discard_cleanups (old_cleanups
);
7831 resume (ecs
->event_thread
->suspend
.stop_signal
);
7834 prepare_to_wait (ecs
);
7837 /* Called when we should continue running the inferior, because the
7838 current event doesn't cause a user visible stop. This does the
7839 resuming part; waiting for the next event is done elsewhere. */
7842 keep_going (struct execution_control_state
*ecs
)
7844 if (ecs
->event_thread
->control
.trap_expected
7845 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7846 ecs
->event_thread
->control
.trap_expected
= 0;
7848 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7849 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7850 keep_going_pass_signal (ecs
);
7853 /* This function normally comes after a resume, before
7854 handle_inferior_event exits. It takes care of any last bits of
7855 housekeeping, and sets the all-important wait_some_more flag. */
7858 prepare_to_wait (struct execution_control_state
*ecs
)
7861 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7863 ecs
->wait_some_more
= 1;
7865 if (!target_is_async_p ())
7866 mark_infrun_async_event_handler ();
7869 /* We are done with the step range of a step/next/si/ni command.
7870 Called once for each n of a "step n" operation. */
7873 end_stepping_range (struct execution_control_state
*ecs
)
7875 ecs
->event_thread
->control
.stop_step
= 1;
7879 /* Several print_*_reason functions to print why the inferior has stopped.
7880 We always print something when the inferior exits, or receives a signal.
7881 The rest of the cases are dealt with later on in normal_stop and
7882 print_it_typical. Ideally there should be a call to one of these
7883 print_*_reason functions functions from handle_inferior_event each time
7884 stop_waiting is called.
7886 Note that we don't call these directly, instead we delegate that to
7887 the interpreters, through observers. Interpreters then call these
7888 with whatever uiout is right. */
7891 print_end_stepping_range_reason (struct ui_out
*uiout
)
7893 /* For CLI-like interpreters, print nothing. */
7895 if (uiout
->is_mi_like_p ())
7897 uiout
->field_string ("reason",
7898 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7903 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7905 annotate_signalled ();
7906 if (uiout
->is_mi_like_p ())
7908 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7909 uiout
->text ("\nProgram terminated with signal ");
7910 annotate_signal_name ();
7911 uiout
->field_string ("signal-name",
7912 gdb_signal_to_name (siggnal
));
7913 annotate_signal_name_end ();
7915 annotate_signal_string ();
7916 uiout
->field_string ("signal-meaning",
7917 gdb_signal_to_string (siggnal
));
7918 annotate_signal_string_end ();
7919 uiout
->text (".\n");
7920 uiout
->text ("The program no longer exists.\n");
7924 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7926 struct inferior
*inf
= current_inferior ();
7927 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
7929 annotate_exited (exitstatus
);
7932 if (uiout
->is_mi_like_p ())
7933 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
7934 uiout
->text ("[Inferior ");
7935 uiout
->text (plongest (inf
->num
));
7937 uiout
->text (pidstr
);
7938 uiout
->text (") exited with code ");
7939 uiout
->field_fmt ("exit-code", "0%o", (unsigned int) exitstatus
);
7940 uiout
->text ("]\n");
7944 if (uiout
->is_mi_like_p ())
7946 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7947 uiout
->text ("[Inferior ");
7948 uiout
->text (plongest (inf
->num
));
7950 uiout
->text (pidstr
);
7951 uiout
->text (") exited normally]\n");
7955 /* Some targets/architectures can do extra processing/display of
7956 segmentation faults. E.g., Intel MPX boundary faults.
7957 Call the architecture dependent function to handle the fault. */
7960 handle_segmentation_fault (struct ui_out
*uiout
)
7962 struct regcache
*regcache
= get_current_regcache ();
7963 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7965 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7966 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7970 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7972 struct thread_info
*thr
= inferior_thread ();
7976 if (uiout
->is_mi_like_p ())
7978 else if (show_thread_that_caused_stop ())
7982 uiout
->text ("\nThread ");
7983 uiout
->field_fmt ("thread-id", "%s", print_thread_id (thr
));
7985 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7988 uiout
->text (" \"");
7989 uiout
->field_fmt ("name", "%s", name
);
7994 uiout
->text ("\nProgram");
7996 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
7997 uiout
->text (" stopped");
8000 uiout
->text (" received signal ");
8001 annotate_signal_name ();
8002 if (uiout
->is_mi_like_p ())
8004 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
8005 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
8006 annotate_signal_name_end ();
8008 annotate_signal_string ();
8009 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
8011 if (siggnal
== GDB_SIGNAL_SEGV
)
8012 handle_segmentation_fault (uiout
);
8014 annotate_signal_string_end ();
8016 uiout
->text (".\n");
8020 print_no_history_reason (struct ui_out
*uiout
)
8022 uiout
->text ("\nNo more reverse-execution history.\n");
8025 /* Print current location without a level number, if we have changed
8026 functions or hit a breakpoint. Print source line if we have one.
8027 bpstat_print contains the logic deciding in detail what to print,
8028 based on the event(s) that just occurred. */
8031 print_stop_location (struct target_waitstatus
*ws
)
8034 enum print_what source_flag
;
8035 int do_frame_printing
= 1;
8036 struct thread_info
*tp
= inferior_thread ();
8038 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8042 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8043 should) carry around the function and does (or should) use
8044 that when doing a frame comparison. */
8045 if (tp
->control
.stop_step
8046 && frame_id_eq (tp
->control
.step_frame_id
,
8047 get_frame_id (get_current_frame ()))
8048 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
8050 /* Finished step, just print source line. */
8051 source_flag
= SRC_LINE
;
8055 /* Print location and source line. */
8056 source_flag
= SRC_AND_LOC
;
8059 case PRINT_SRC_AND_LOC
:
8060 /* Print location and source line. */
8061 source_flag
= SRC_AND_LOC
;
8063 case PRINT_SRC_ONLY
:
8064 source_flag
= SRC_LINE
;
8067 /* Something bogus. */
8068 source_flag
= SRC_LINE
;
8069 do_frame_printing
= 0;
8072 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8075 /* The behavior of this routine with respect to the source
8077 SRC_LINE: Print only source line
8078 LOCATION: Print only location
8079 SRC_AND_LOC: Print location and source line. */
8080 if (do_frame_printing
)
8081 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8087 print_stop_event (struct ui_out
*uiout
)
8089 struct target_waitstatus last
;
8091 struct thread_info
*tp
;
8093 get_last_target_status (&last_ptid
, &last
);
8096 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
8098 print_stop_location (&last
);
8100 /* Display the auto-display expressions. */
8104 tp
= inferior_thread ();
8105 if (tp
->thread_fsm
!= NULL
8106 && thread_fsm_finished_p (tp
->thread_fsm
))
8108 struct return_value_info
*rv
;
8110 rv
= thread_fsm_return_value (tp
->thread_fsm
);
8112 print_return_value (uiout
, rv
);
8119 maybe_remove_breakpoints (void)
8121 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
8123 if (remove_breakpoints ())
8125 target_terminal_ours_for_output ();
8126 printf_filtered (_("Cannot remove breakpoints because "
8127 "program is no longer writable.\nFurther "
8128 "execution is probably impossible.\n"));
8133 /* The execution context that just caused a normal stop. */
8140 /* The event PTID. */
8144 /* If stopp for a thread event, this is the thread that caused the
8146 struct thread_info
*thread
;
8148 /* The inferior that caused the stop. */
8152 /* Returns a new stop context. If stopped for a thread event, this
8153 takes a strong reference to the thread. */
8155 static struct stop_context
*
8156 save_stop_context (void)
8158 struct stop_context
*sc
= XNEW (struct stop_context
);
8160 sc
->stop_id
= get_stop_id ();
8161 sc
->ptid
= inferior_ptid
;
8162 sc
->inf_num
= current_inferior ()->num
;
8164 if (!ptid_equal (inferior_ptid
, null_ptid
))
8166 /* Take a strong reference so that the thread can't be deleted
8168 sc
->thread
= inferior_thread ();
8169 sc
->thread
->incref ();
8177 /* Release a stop context previously created with save_stop_context.
8178 Releases the strong reference to the thread as well. */
8181 release_stop_context_cleanup (void *arg
)
8183 struct stop_context
*sc
= (struct stop_context
*) arg
;
8185 if (sc
->thread
!= NULL
)
8186 sc
->thread
->decref ();
8190 /* Return true if the current context no longer matches the saved stop
8194 stop_context_changed (struct stop_context
*prev
)
8196 if (!ptid_equal (prev
->ptid
, inferior_ptid
))
8198 if (prev
->inf_num
!= current_inferior ()->num
)
8200 if (prev
->thread
!= NULL
&& prev
->thread
->state
!= THREAD_STOPPED
)
8202 if (get_stop_id () != prev
->stop_id
)
8212 struct target_waitstatus last
;
8214 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
8217 get_last_target_status (&last_ptid
, &last
);
8221 /* If an exception is thrown from this point on, make sure to
8222 propagate GDB's knowledge of the executing state to the
8223 frontend/user running state. A QUIT is an easy exception to see
8224 here, so do this before any filtered output. */
8226 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
8227 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8228 || last
.kind
== TARGET_WAITKIND_EXITED
)
8230 /* On some targets, we may still have live threads in the
8231 inferior when we get a process exit event. E.g., for
8232 "checkpoint", when the current checkpoint/fork exits,
8233 linux-fork.c automatically switches to another fork from
8234 within target_mourn_inferior. */
8235 if (!ptid_equal (inferior_ptid
, null_ptid
))
8237 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
8238 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
8241 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8242 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
8244 /* As we're presenting a stop, and potentially removing breakpoints,
8245 update the thread list so we can tell whether there are threads
8246 running on the target. With target remote, for example, we can
8247 only learn about new threads when we explicitly update the thread
8248 list. Do this before notifying the interpreters about signal
8249 stops, end of stepping ranges, etc., so that the "new thread"
8250 output is emitted before e.g., "Program received signal FOO",
8251 instead of after. */
8252 update_thread_list ();
8254 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8255 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
8257 /* As with the notification of thread events, we want to delay
8258 notifying the user that we've switched thread context until
8259 the inferior actually stops.
8261 There's no point in saying anything if the inferior has exited.
8262 Note that SIGNALLED here means "exited with a signal", not
8263 "received a signal".
8265 Also skip saying anything in non-stop mode. In that mode, as we
8266 don't want GDB to switch threads behind the user's back, to avoid
8267 races where the user is typing a command to apply to thread x,
8268 but GDB switches to thread y before the user finishes entering
8269 the command, fetch_inferior_event installs a cleanup to restore
8270 the current thread back to the thread the user had selected right
8271 after this event is handled, so we're not really switching, only
8272 informing of a stop. */
8274 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
8275 && target_has_execution
8276 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8277 && last
.kind
!= TARGET_WAITKIND_EXITED
8278 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8280 SWITCH_THRU_ALL_UIS ()
8282 target_terminal_ours_for_output ();
8283 printf_filtered (_("[Switching to %s]\n"),
8284 target_pid_to_str (inferior_ptid
));
8285 annotate_thread_changed ();
8287 previous_inferior_ptid
= inferior_ptid
;
8290 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8292 SWITCH_THRU_ALL_UIS ()
8293 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8295 target_terminal_ours_for_output ();
8296 printf_filtered (_("No unwaited-for children left.\n"));
8300 /* Note: this depends on the update_thread_list call above. */
8301 maybe_remove_breakpoints ();
8303 /* If an auto-display called a function and that got a signal,
8304 delete that auto-display to avoid an infinite recursion. */
8306 if (stopped_by_random_signal
)
8307 disable_current_display ();
8309 SWITCH_THRU_ALL_UIS ()
8311 async_enable_stdin ();
8314 /* Let the user/frontend see the threads as stopped. */
8315 do_cleanups (old_chain
);
8317 /* Select innermost stack frame - i.e., current frame is frame 0,
8318 and current location is based on that. Handle the case where the
8319 dummy call is returning after being stopped. E.g. the dummy call
8320 previously hit a breakpoint. (If the dummy call returns
8321 normally, we won't reach here.) Do this before the stop hook is
8322 run, so that it doesn't get to see the temporary dummy frame,
8323 which is not where we'll present the stop. */
8324 if (has_stack_frames ())
8326 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8328 /* Pop the empty frame that contains the stack dummy. This
8329 also restores inferior state prior to the call (struct
8330 infcall_suspend_state). */
8331 struct frame_info
*frame
= get_current_frame ();
8333 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8335 /* frame_pop calls reinit_frame_cache as the last thing it
8336 does which means there's now no selected frame. */
8339 select_frame (get_current_frame ());
8341 /* Set the current source location. */
8342 set_current_sal_from_frame (get_current_frame ());
8345 /* Look up the hook_stop and run it (CLI internally handles problem
8346 of stop_command's pre-hook not existing). */
8347 if (stop_command
!= NULL
)
8349 struct stop_context
*saved_context
= save_stop_context ();
8350 struct cleanup
*old_chain
8351 = make_cleanup (release_stop_context_cleanup
, saved_context
);
8353 catch_errors (hook_stop_stub
, stop_command
,
8354 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
8356 /* If the stop hook resumes the target, then there's no point in
8357 trying to notify about the previous stop; its context is
8358 gone. Likewise if the command switches thread or inferior --
8359 the observers would print a stop for the wrong
8361 if (stop_context_changed (saved_context
))
8363 do_cleanups (old_chain
);
8366 do_cleanups (old_chain
);
8369 /* Notify observers about the stop. This is where the interpreters
8370 print the stop event. */
8371 if (!ptid_equal (inferior_ptid
, null_ptid
))
8372 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
8375 observer_notify_normal_stop (NULL
, stop_print_frame
);
8377 annotate_stopped ();
8379 if (target_has_execution
)
8381 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8382 && last
.kind
!= TARGET_WAITKIND_EXITED
)
8383 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8384 Delete any breakpoint that is to be deleted at the next stop. */
8385 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8388 /* Try to get rid of automatically added inferiors that are no
8389 longer needed. Keeping those around slows down things linearly.
8390 Note that this never removes the current inferior. */
8397 hook_stop_stub (void *cmd
)
8399 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
8404 signal_stop_state (int signo
)
8406 return signal_stop
[signo
];
8410 signal_print_state (int signo
)
8412 return signal_print
[signo
];
8416 signal_pass_state (int signo
)
8418 return signal_program
[signo
];
8422 signal_cache_update (int signo
)
8426 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8427 signal_cache_update (signo
);
8432 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8433 && signal_print
[signo
] == 0
8434 && signal_program
[signo
] == 1
8435 && signal_catch
[signo
] == 0);
8439 signal_stop_update (int signo
, int state
)
8441 int ret
= signal_stop
[signo
];
8443 signal_stop
[signo
] = state
;
8444 signal_cache_update (signo
);
8449 signal_print_update (int signo
, int state
)
8451 int ret
= signal_print
[signo
];
8453 signal_print
[signo
] = state
;
8454 signal_cache_update (signo
);
8459 signal_pass_update (int signo
, int state
)
8461 int ret
= signal_program
[signo
];
8463 signal_program
[signo
] = state
;
8464 signal_cache_update (signo
);
8468 /* Update the global 'signal_catch' from INFO and notify the
8472 signal_catch_update (const unsigned int *info
)
8476 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8477 signal_catch
[i
] = info
[i
] > 0;
8478 signal_cache_update (-1);
8479 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8483 sig_print_header (void)
8485 printf_filtered (_("Signal Stop\tPrint\tPass "
8486 "to program\tDescription\n"));
8490 sig_print_info (enum gdb_signal oursig
)
8492 const char *name
= gdb_signal_to_name (oursig
);
8493 int name_padding
= 13 - strlen (name
);
8495 if (name_padding
<= 0)
8498 printf_filtered ("%s", name
);
8499 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8500 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8501 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8502 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8503 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8506 /* Specify how various signals in the inferior should be handled. */
8509 handle_command (char *args
, int from_tty
)
8512 int digits
, wordlen
;
8513 int sigfirst
, signum
, siglast
;
8514 enum gdb_signal oursig
;
8517 unsigned char *sigs
;
8518 struct cleanup
*old_chain
;
8522 error_no_arg (_("signal to handle"));
8525 /* Allocate and zero an array of flags for which signals to handle. */
8527 nsigs
= (int) GDB_SIGNAL_LAST
;
8528 sigs
= (unsigned char *) alloca (nsigs
);
8529 memset (sigs
, 0, nsigs
);
8531 /* Break the command line up into args. */
8533 argv
= gdb_buildargv (args
);
8534 old_chain
= make_cleanup_freeargv (argv
);
8536 /* Walk through the args, looking for signal oursigs, signal names, and
8537 actions. Signal numbers and signal names may be interspersed with
8538 actions, with the actions being performed for all signals cumulatively
8539 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8541 while (*argv
!= NULL
)
8543 wordlen
= strlen (*argv
);
8544 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
8548 sigfirst
= siglast
= -1;
8550 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
8552 /* Apply action to all signals except those used by the
8553 debugger. Silently skip those. */
8556 siglast
= nsigs
- 1;
8558 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
8560 SET_SIGS (nsigs
, sigs
, signal_stop
);
8561 SET_SIGS (nsigs
, sigs
, signal_print
);
8563 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
8565 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8567 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
8569 SET_SIGS (nsigs
, sigs
, signal_print
);
8571 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
8573 SET_SIGS (nsigs
, sigs
, signal_program
);
8575 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
8577 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8579 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
8581 SET_SIGS (nsigs
, sigs
, signal_program
);
8583 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
8585 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8586 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8588 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
8590 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8592 else if (digits
> 0)
8594 /* It is numeric. The numeric signal refers to our own
8595 internal signal numbering from target.h, not to host/target
8596 signal number. This is a feature; users really should be
8597 using symbolic names anyway, and the common ones like
8598 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8600 sigfirst
= siglast
= (int)
8601 gdb_signal_from_command (atoi (*argv
));
8602 if ((*argv
)[digits
] == '-')
8605 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
8607 if (sigfirst
> siglast
)
8609 /* Bet he didn't figure we'd think of this case... */
8617 oursig
= gdb_signal_from_name (*argv
);
8618 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8620 sigfirst
= siglast
= (int) oursig
;
8624 /* Not a number and not a recognized flag word => complain. */
8625 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
8629 /* If any signal numbers or symbol names were found, set flags for
8630 which signals to apply actions to. */
8632 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8634 switch ((enum gdb_signal
) signum
)
8636 case GDB_SIGNAL_TRAP
:
8637 case GDB_SIGNAL_INT
:
8638 if (!allsigs
&& !sigs
[signum
])
8640 if (query (_("%s is used by the debugger.\n\
8641 Are you sure you want to change it? "),
8642 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8648 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8649 gdb_flush (gdb_stdout
);
8654 case GDB_SIGNAL_DEFAULT
:
8655 case GDB_SIGNAL_UNKNOWN
:
8656 /* Make sure that "all" doesn't print these. */
8667 for (signum
= 0; signum
< nsigs
; signum
++)
8670 signal_cache_update (-1);
8671 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8672 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8676 /* Show the results. */
8677 sig_print_header ();
8678 for (; signum
< nsigs
; signum
++)
8680 sig_print_info ((enum gdb_signal
) signum
);
8686 do_cleanups (old_chain
);
8689 /* Complete the "handle" command. */
8691 static VEC (char_ptr
) *
8692 handle_completer (struct cmd_list_element
*ignore
,
8693 const char *text
, const char *word
)
8695 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
8696 static const char * const keywords
[] =
8710 vec_signals
= signal_completer (ignore
, text
, word
);
8711 vec_keywords
= complete_on_enum (keywords
, word
, word
);
8713 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
8714 VEC_free (char_ptr
, vec_signals
);
8715 VEC_free (char_ptr
, vec_keywords
);
8720 gdb_signal_from_command (int num
)
8722 if (num
>= 1 && num
<= 15)
8723 return (enum gdb_signal
) num
;
8724 error (_("Only signals 1-15 are valid as numeric signals.\n\
8725 Use \"info signals\" for a list of symbolic signals."));
8728 /* Print current contents of the tables set by the handle command.
8729 It is possible we should just be printing signals actually used
8730 by the current target (but for things to work right when switching
8731 targets, all signals should be in the signal tables). */
8734 signals_info (char *signum_exp
, int from_tty
)
8736 enum gdb_signal oursig
;
8738 sig_print_header ();
8742 /* First see if this is a symbol name. */
8743 oursig
= gdb_signal_from_name (signum_exp
);
8744 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8746 /* No, try numeric. */
8748 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8750 sig_print_info (oursig
);
8754 printf_filtered ("\n");
8755 /* These ugly casts brought to you by the native VAX compiler. */
8756 for (oursig
= GDB_SIGNAL_FIRST
;
8757 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8758 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8762 if (oursig
!= GDB_SIGNAL_UNKNOWN
8763 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8764 sig_print_info (oursig
);
8767 printf_filtered (_("\nUse the \"handle\" command "
8768 "to change these tables.\n"));
8771 /* The $_siginfo convenience variable is a bit special. We don't know
8772 for sure the type of the value until we actually have a chance to
8773 fetch the data. The type can change depending on gdbarch, so it is
8774 also dependent on which thread you have selected.
8776 1. making $_siginfo be an internalvar that creates a new value on
8779 2. making the value of $_siginfo be an lval_computed value. */
8781 /* This function implements the lval_computed support for reading a
8785 siginfo_value_read (struct value
*v
)
8787 LONGEST transferred
;
8789 /* If we can access registers, so can we access $_siginfo. Likewise
8791 validate_registers_access ();
8794 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8796 value_contents_all_raw (v
),
8798 TYPE_LENGTH (value_type (v
)));
8800 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8801 error (_("Unable to read siginfo"));
8804 /* This function implements the lval_computed support for writing a
8808 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8810 LONGEST transferred
;
8812 /* If we can access registers, so can we access $_siginfo. Likewise
8814 validate_registers_access ();
8816 transferred
= target_write (¤t_target
,
8817 TARGET_OBJECT_SIGNAL_INFO
,
8819 value_contents_all_raw (fromval
),
8821 TYPE_LENGTH (value_type (fromval
)));
8823 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8824 error (_("Unable to write siginfo"));
8827 static const struct lval_funcs siginfo_value_funcs
=
8833 /* Return a new value with the correct type for the siginfo object of
8834 the current thread using architecture GDBARCH. Return a void value
8835 if there's no object available. */
8837 static struct value
*
8838 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8841 if (target_has_stack
8842 && !ptid_equal (inferior_ptid
, null_ptid
)
8843 && gdbarch_get_siginfo_type_p (gdbarch
))
8845 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8847 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8850 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8854 /* infcall_suspend_state contains state about the program itself like its
8855 registers and any signal it received when it last stopped.
8856 This state must be restored regardless of how the inferior function call
8857 ends (either successfully, or after it hits a breakpoint or signal)
8858 if the program is to properly continue where it left off. */
8860 struct infcall_suspend_state
8862 struct thread_suspend_state thread_suspend
;
8866 struct regcache
*registers
;
8868 /* Format of SIGINFO_DATA or NULL if it is not present. */
8869 struct gdbarch
*siginfo_gdbarch
;
8871 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8872 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8873 content would be invalid. */
8874 gdb_byte
*siginfo_data
;
8877 struct infcall_suspend_state
*
8878 save_infcall_suspend_state (void)
8880 struct infcall_suspend_state
*inf_state
;
8881 struct thread_info
*tp
= inferior_thread ();
8882 struct regcache
*regcache
= get_current_regcache ();
8883 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8884 gdb_byte
*siginfo_data
= NULL
;
8886 if (gdbarch_get_siginfo_type_p (gdbarch
))
8888 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8889 size_t len
= TYPE_LENGTH (type
);
8890 struct cleanup
*back_to
;
8892 siginfo_data
= (gdb_byte
*) xmalloc (len
);
8893 back_to
= make_cleanup (xfree
, siginfo_data
);
8895 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8896 siginfo_data
, 0, len
) == len
)
8897 discard_cleanups (back_to
);
8900 /* Errors ignored. */
8901 do_cleanups (back_to
);
8902 siginfo_data
= NULL
;
8906 inf_state
= XCNEW (struct infcall_suspend_state
);
8910 inf_state
->siginfo_gdbarch
= gdbarch
;
8911 inf_state
->siginfo_data
= siginfo_data
;
8914 inf_state
->thread_suspend
= tp
->suspend
;
8916 /* run_inferior_call will not use the signal due to its `proceed' call with
8917 GDB_SIGNAL_0 anyway. */
8918 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8920 inf_state
->stop_pc
= stop_pc
;
8922 inf_state
->registers
= regcache_dup (regcache
);
8927 /* Restore inferior session state to INF_STATE. */
8930 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8932 struct thread_info
*tp
= inferior_thread ();
8933 struct regcache
*regcache
= get_current_regcache ();
8934 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8936 tp
->suspend
= inf_state
->thread_suspend
;
8938 stop_pc
= inf_state
->stop_pc
;
8940 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8942 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8944 /* Errors ignored. */
8945 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8946 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8949 /* The inferior can be gone if the user types "print exit(0)"
8950 (and perhaps other times). */
8951 if (target_has_execution
)
8952 /* NB: The register write goes through to the target. */
8953 regcache_cpy (regcache
, inf_state
->registers
);
8955 discard_infcall_suspend_state (inf_state
);
8959 do_restore_infcall_suspend_state_cleanup (void *state
)
8961 restore_infcall_suspend_state ((struct infcall_suspend_state
*) state
);
8965 make_cleanup_restore_infcall_suspend_state
8966 (struct infcall_suspend_state
*inf_state
)
8968 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
8972 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8974 regcache_xfree (inf_state
->registers
);
8975 xfree (inf_state
->siginfo_data
);
8980 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8982 return inf_state
->registers
;
8985 /* infcall_control_state contains state regarding gdb's control of the
8986 inferior itself like stepping control. It also contains session state like
8987 the user's currently selected frame. */
8989 struct infcall_control_state
8991 struct thread_control_state thread_control
;
8992 struct inferior_control_state inferior_control
;
8995 enum stop_stack_kind stop_stack_dummy
;
8996 int stopped_by_random_signal
;
8998 /* ID if the selected frame when the inferior function call was made. */
8999 struct frame_id selected_frame_id
;
9002 /* Save all of the information associated with the inferior<==>gdb
9005 struct infcall_control_state
*
9006 save_infcall_control_state (void)
9008 struct infcall_control_state
*inf_status
=
9009 XNEW (struct infcall_control_state
);
9010 struct thread_info
*tp
= inferior_thread ();
9011 struct inferior
*inf
= current_inferior ();
9013 inf_status
->thread_control
= tp
->control
;
9014 inf_status
->inferior_control
= inf
->control
;
9016 tp
->control
.step_resume_breakpoint
= NULL
;
9017 tp
->control
.exception_resume_breakpoint
= NULL
;
9019 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9020 chain. If caller's caller is walking the chain, they'll be happier if we
9021 hand them back the original chain when restore_infcall_control_state is
9023 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9026 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9027 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9029 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
9035 restore_selected_frame (void *args
)
9037 struct frame_id
*fid
= (struct frame_id
*) args
;
9038 struct frame_info
*frame
;
9040 frame
= frame_find_by_id (*fid
);
9042 /* If inf_status->selected_frame_id is NULL, there was no previously
9046 warning (_("Unable to restore previously selected frame."));
9050 select_frame (frame
);
9055 /* Restore inferior session state to INF_STATUS. */
9058 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9060 struct thread_info
*tp
= inferior_thread ();
9061 struct inferior
*inf
= current_inferior ();
9063 if (tp
->control
.step_resume_breakpoint
)
9064 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9066 if (tp
->control
.exception_resume_breakpoint
)
9067 tp
->control
.exception_resume_breakpoint
->disposition
9068 = disp_del_at_next_stop
;
9070 /* Handle the bpstat_copy of the chain. */
9071 bpstat_clear (&tp
->control
.stop_bpstat
);
9073 tp
->control
= inf_status
->thread_control
;
9074 inf
->control
= inf_status
->inferior_control
;
9077 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9078 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9080 if (target_has_stack
)
9082 /* The point of catch_errors is that if the stack is clobbered,
9083 walking the stack might encounter a garbage pointer and
9084 error() trying to dereference it. */
9086 (restore_selected_frame
, &inf_status
->selected_frame_id
,
9087 "Unable to restore previously selected frame:\n",
9088 RETURN_MASK_ERROR
) == 0)
9089 /* Error in restoring the selected frame. Select the innermost
9091 select_frame (get_current_frame ());
9098 do_restore_infcall_control_state_cleanup (void *sts
)
9100 restore_infcall_control_state ((struct infcall_control_state
*) sts
);
9104 make_cleanup_restore_infcall_control_state
9105 (struct infcall_control_state
*inf_status
)
9107 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
9111 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9113 if (inf_status
->thread_control
.step_resume_breakpoint
)
9114 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9115 = disp_del_at_next_stop
;
9117 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9118 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9119 = disp_del_at_next_stop
;
9121 /* See save_infcall_control_state for info on stop_bpstat. */
9122 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9127 /* restore_inferior_ptid() will be used by the cleanup machinery
9128 to restore the inferior_ptid value saved in a call to
9129 save_inferior_ptid(). */
9132 restore_inferior_ptid (void *arg
)
9134 ptid_t
*saved_ptid_ptr
= (ptid_t
*) arg
;
9136 inferior_ptid
= *saved_ptid_ptr
;
9140 /* Save the value of inferior_ptid so that it may be restored by a
9141 later call to do_cleanups(). Returns the struct cleanup pointer
9142 needed for later doing the cleanup. */
9145 save_inferior_ptid (void)
9147 ptid_t
*saved_ptid_ptr
= XNEW (ptid_t
);
9149 *saved_ptid_ptr
= inferior_ptid
;
9150 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
9156 clear_exit_convenience_vars (void)
9158 clear_internalvar (lookup_internalvar ("_exitsignal"));
9159 clear_internalvar (lookup_internalvar ("_exitcode"));
9163 /* User interface for reverse debugging:
9164 Set exec-direction / show exec-direction commands
9165 (returns error unless target implements to_set_exec_direction method). */
9167 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9168 static const char exec_forward
[] = "forward";
9169 static const char exec_reverse
[] = "reverse";
9170 static const char *exec_direction
= exec_forward
;
9171 static const char *const exec_direction_names
[] = {
9178 set_exec_direction_func (char *args
, int from_tty
,
9179 struct cmd_list_element
*cmd
)
9181 if (target_can_execute_reverse
)
9183 if (!strcmp (exec_direction
, exec_forward
))
9184 execution_direction
= EXEC_FORWARD
;
9185 else if (!strcmp (exec_direction
, exec_reverse
))
9186 execution_direction
= EXEC_REVERSE
;
9190 exec_direction
= exec_forward
;
9191 error (_("Target does not support this operation."));
9196 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9197 struct cmd_list_element
*cmd
, const char *value
)
9199 switch (execution_direction
) {
9201 fprintf_filtered (out
, _("Forward.\n"));
9204 fprintf_filtered (out
, _("Reverse.\n"));
9207 internal_error (__FILE__
, __LINE__
,
9208 _("bogus execution_direction value: %d"),
9209 (int) execution_direction
);
9214 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9215 struct cmd_list_element
*c
, const char *value
)
9217 fprintf_filtered (file
, _("Resuming the execution of threads "
9218 "of all processes is %s.\n"), value
);
9221 /* Implementation of `siginfo' variable. */
9223 static const struct internalvar_funcs siginfo_funcs
=
9230 /* Callback for infrun's target events source. This is marked when a
9231 thread has a pending status to process. */
9234 infrun_async_inferior_event_handler (gdb_client_data data
)
9236 inferior_event_handler (INF_REG_EVENT
, NULL
);
9240 _initialize_infrun (void)
9244 struct cmd_list_element
*c
;
9246 /* Register extra event sources in the event loop. */
9247 infrun_async_inferior_event_token
9248 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
9250 add_info ("signals", signals_info
, _("\
9251 What debugger does when program gets various signals.\n\
9252 Specify a signal as argument to print info on that signal only."));
9253 add_info_alias ("handle", "signals", 0);
9255 c
= add_com ("handle", class_run
, handle_command
, _("\
9256 Specify how to handle signals.\n\
9257 Usage: handle SIGNAL [ACTIONS]\n\
9258 Args are signals and actions to apply to those signals.\n\
9259 If no actions are specified, the current settings for the specified signals\n\
9260 will be displayed instead.\n\
9262 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9263 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9264 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9265 The special arg \"all\" is recognized to mean all signals except those\n\
9266 used by the debugger, typically SIGTRAP and SIGINT.\n\
9268 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9269 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9270 Stop means reenter debugger if this signal happens (implies print).\n\
9271 Print means print a message if this signal happens.\n\
9272 Pass means let program see this signal; otherwise program doesn't know.\n\
9273 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9274 Pass and Stop may be combined.\n\
9276 Multiple signals may be specified. Signal numbers and signal names\n\
9277 may be interspersed with actions, with the actions being performed for\n\
9278 all signals cumulatively specified."));
9279 set_cmd_completer (c
, handle_completer
);
9282 stop_command
= add_cmd ("stop", class_obscure
,
9283 not_just_help_class_command
, _("\
9284 There is no `stop' command, but you can set a hook on `stop'.\n\
9285 This allows you to set a list of commands to be run each time execution\n\
9286 of the program stops."), &cmdlist
);
9288 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
9289 Set inferior debugging."), _("\
9290 Show inferior debugging."), _("\
9291 When non-zero, inferior specific debugging is enabled."),
9294 &setdebuglist
, &showdebuglist
);
9296 add_setshow_boolean_cmd ("displaced", class_maintenance
,
9297 &debug_displaced
, _("\
9298 Set displaced stepping debugging."), _("\
9299 Show displaced stepping debugging."), _("\
9300 When non-zero, displaced stepping specific debugging is enabled."),
9302 show_debug_displaced
,
9303 &setdebuglist
, &showdebuglist
);
9305 add_setshow_boolean_cmd ("non-stop", no_class
,
9307 Set whether gdb controls the inferior in non-stop mode."), _("\
9308 Show whether gdb controls the inferior in non-stop mode."), _("\
9309 When debugging a multi-threaded program and this setting is\n\
9310 off (the default, also called all-stop mode), when one thread stops\n\
9311 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9312 all other threads in the program while you interact with the thread of\n\
9313 interest. When you continue or step a thread, you can allow the other\n\
9314 threads to run, or have them remain stopped, but while you inspect any\n\
9315 thread's state, all threads stop.\n\
9317 In non-stop mode, when one thread stops, other threads can continue\n\
9318 to run freely. You'll be able to step each thread independently,\n\
9319 leave it stopped or free to run as needed."),
9325 numsigs
= (int) GDB_SIGNAL_LAST
;
9326 signal_stop
= XNEWVEC (unsigned char, numsigs
);
9327 signal_print
= XNEWVEC (unsigned char, numsigs
);
9328 signal_program
= XNEWVEC (unsigned char, numsigs
);
9329 signal_catch
= XNEWVEC (unsigned char, numsigs
);
9330 signal_pass
= XNEWVEC (unsigned char, numsigs
);
9331 for (i
= 0; i
< numsigs
; i
++)
9334 signal_print
[i
] = 1;
9335 signal_program
[i
] = 1;
9336 signal_catch
[i
] = 0;
9339 /* Signals caused by debugger's own actions should not be given to
9340 the program afterwards.
9342 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9343 explicitly specifies that it should be delivered to the target
9344 program. Typically, that would occur when a user is debugging a
9345 target monitor on a simulator: the target monitor sets a
9346 breakpoint; the simulator encounters this breakpoint and halts
9347 the simulation handing control to GDB; GDB, noting that the stop
9348 address doesn't map to any known breakpoint, returns control back
9349 to the simulator; the simulator then delivers the hardware
9350 equivalent of a GDB_SIGNAL_TRAP to the program being
9352 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9353 signal_program
[GDB_SIGNAL_INT
] = 0;
9355 /* Signals that are not errors should not normally enter the debugger. */
9356 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9357 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9358 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9359 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9360 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9361 signal_print
[GDB_SIGNAL_PROF
] = 0;
9362 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9363 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9364 signal_stop
[GDB_SIGNAL_IO
] = 0;
9365 signal_print
[GDB_SIGNAL_IO
] = 0;
9366 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9367 signal_print
[GDB_SIGNAL_POLL
] = 0;
9368 signal_stop
[GDB_SIGNAL_URG
] = 0;
9369 signal_print
[GDB_SIGNAL_URG
] = 0;
9370 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9371 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9372 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9373 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9375 /* These signals are used internally by user-level thread
9376 implementations. (See signal(5) on Solaris.) Like the above
9377 signals, a healthy program receives and handles them as part of
9378 its normal operation. */
9379 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9380 signal_print
[GDB_SIGNAL_LWP
] = 0;
9381 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9382 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9383 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9384 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9385 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9386 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9388 /* Update cached state. */
9389 signal_cache_update (-1);
9391 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9392 &stop_on_solib_events
, _("\
9393 Set stopping for shared library events."), _("\
9394 Show stopping for shared library events."), _("\
9395 If nonzero, gdb will give control to the user when the dynamic linker\n\
9396 notifies gdb of shared library events. The most common event of interest\n\
9397 to the user would be loading/unloading of a new library."),
9398 set_stop_on_solib_events
,
9399 show_stop_on_solib_events
,
9400 &setlist
, &showlist
);
9402 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9403 follow_fork_mode_kind_names
,
9404 &follow_fork_mode_string
, _("\
9405 Set debugger response to a program call of fork or vfork."), _("\
9406 Show debugger response to a program call of fork or vfork."), _("\
9407 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9408 parent - the original process is debugged after a fork\n\
9409 child - the new process is debugged after a fork\n\
9410 The unfollowed process will continue to run.\n\
9411 By default, the debugger will follow the parent process."),
9413 show_follow_fork_mode_string
,
9414 &setlist
, &showlist
);
9416 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9417 follow_exec_mode_names
,
9418 &follow_exec_mode_string
, _("\
9419 Set debugger response to a program call of exec."), _("\
9420 Show debugger response to a program call of exec."), _("\
9421 An exec call replaces the program image of a process.\n\
9423 follow-exec-mode can be:\n\
9425 new - the debugger creates a new inferior and rebinds the process\n\
9426 to this new inferior. The program the process was running before\n\
9427 the exec call can be restarted afterwards by restarting the original\n\
9430 same - the debugger keeps the process bound to the same inferior.\n\
9431 The new executable image replaces the previous executable loaded in\n\
9432 the inferior. Restarting the inferior after the exec call restarts\n\
9433 the executable the process was running after the exec call.\n\
9435 By default, the debugger will use the same inferior."),
9437 show_follow_exec_mode_string
,
9438 &setlist
, &showlist
);
9440 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9441 scheduler_enums
, &scheduler_mode
, _("\
9442 Set mode for locking scheduler during execution."), _("\
9443 Show mode for locking scheduler during execution."), _("\
9444 off == no locking (threads may preempt at any time)\n\
9445 on == full locking (no thread except the current thread may run)\n\
9446 This applies to both normal execution and replay mode.\n\
9447 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9448 In this mode, other threads may run during other commands.\n\
9449 This applies to both normal execution and replay mode.\n\
9450 replay == scheduler locked in replay mode and unlocked during normal execution."),
9451 set_schedlock_func
, /* traps on target vector */
9452 show_scheduler_mode
,
9453 &setlist
, &showlist
);
9455 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9456 Set mode for resuming threads of all processes."), _("\
9457 Show mode for resuming threads of all processes."), _("\
9458 When on, execution commands (such as 'continue' or 'next') resume all\n\
9459 threads of all processes. When off (which is the default), execution\n\
9460 commands only resume the threads of the current process. The set of\n\
9461 threads that are resumed is further refined by the scheduler-locking\n\
9462 mode (see help set scheduler-locking)."),
9464 show_schedule_multiple
,
9465 &setlist
, &showlist
);
9467 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9468 Set mode of the step operation."), _("\
9469 Show mode of the step operation."), _("\
9470 When set, doing a step over a function without debug line information\n\
9471 will stop at the first instruction of that function. Otherwise, the\n\
9472 function is skipped and the step command stops at a different source line."),
9474 show_step_stop_if_no_debug
,
9475 &setlist
, &showlist
);
9477 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9478 &can_use_displaced_stepping
, _("\
9479 Set debugger's willingness to use displaced stepping."), _("\
9480 Show debugger's willingness to use displaced stepping."), _("\
9481 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9482 supported by the target architecture. If off, gdb will not use displaced\n\
9483 stepping to step over breakpoints, even if such is supported by the target\n\
9484 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9485 if the target architecture supports it and non-stop mode is active, but will not\n\
9486 use it in all-stop mode (see help set non-stop)."),
9488 show_can_use_displaced_stepping
,
9489 &setlist
, &showlist
);
9491 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9492 &exec_direction
, _("Set direction of execution.\n\
9493 Options are 'forward' or 'reverse'."),
9494 _("Show direction of execution (forward/reverse)."),
9495 _("Tells gdb whether to execute forward or backward."),
9496 set_exec_direction_func
, show_exec_direction_func
,
9497 &setlist
, &showlist
);
9499 /* Set/show detach-on-fork: user-settable mode. */
9501 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9502 Set whether gdb will detach the child of a fork."), _("\
9503 Show whether gdb will detach the child of a fork."), _("\
9504 Tells gdb whether to detach the child of a fork."),
9505 NULL
, NULL
, &setlist
, &showlist
);
9507 /* Set/show disable address space randomization mode. */
9509 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9510 &disable_randomization
, _("\
9511 Set disabling of debuggee's virtual address space randomization."), _("\
9512 Show disabling of debuggee's virtual address space randomization."), _("\
9513 When this mode is on (which is the default), randomization of the virtual\n\
9514 address space is disabled. Standalone programs run with the randomization\n\
9515 enabled by default on some platforms."),
9516 &set_disable_randomization
,
9517 &show_disable_randomization
,
9518 &setlist
, &showlist
);
9520 /* ptid initializations */
9521 inferior_ptid
= null_ptid
;
9522 target_last_wait_ptid
= minus_one_ptid
;
9524 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
9525 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
9526 observer_attach_thread_exit (infrun_thread_thread_exit
);
9527 observer_attach_inferior_exit (infrun_inferior_exit
);
9529 /* Explicitly create without lookup, since that tries to create a
9530 value with a void typed value, and when we get here, gdbarch
9531 isn't initialized yet. At this point, we're quite sure there
9532 isn't another convenience variable of the same name. */
9533 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9535 add_setshow_boolean_cmd ("observer", no_class
,
9536 &observer_mode_1
, _("\
9537 Set whether gdb controls the inferior in observer mode."), _("\
9538 Show whether gdb controls the inferior in observer mode."), _("\
9539 In observer mode, GDB can get data from the inferior, but not\n\
9540 affect its execution. Registers and memory may not be changed,\n\
9541 breakpoints may not be set, and the program cannot be interrupted\n\