1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2016 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 #include "event-loop.h"
65 #include "thread-fsm.h"
66 #include "common/enum-flags.h"
68 /* Prototypes for local functions */
70 static void signals_info (char *, int);
72 static void handle_command (char *, int);
74 static void sig_print_info (enum gdb_signal
);
76 static void sig_print_header (void);
78 static void resume_cleanups (void *);
80 static int hook_stop_stub (void *);
82 static int restore_selected_frame (void *);
84 static int follow_fork (void);
86 static int follow_fork_inferior (int follow_child
, int detach_fork
);
88 static void follow_inferior_reset_breakpoints (void);
90 static void set_schedlock_func (char *args
, int from_tty
,
91 struct cmd_list_element
*c
);
93 static int currently_stepping (struct thread_info
*tp
);
95 void _initialize_infrun (void);
97 void nullify_last_target_wait_ptid (void);
99 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
101 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
103 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
105 static int maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
);
107 /* Asynchronous signal handler registered as event loop source for
108 when we have pending events ready to be passed to the core. */
109 static struct async_event_handler
*infrun_async_inferior_event_token
;
111 /* Stores whether infrun_async was previously enabled or disabled.
112 Starts off as -1, indicating "never enabled/disabled". */
113 static int infrun_is_async
= -1;
118 infrun_async (int enable
)
120 if (infrun_is_async
!= enable
)
122 infrun_is_async
= enable
;
125 fprintf_unfiltered (gdb_stdlog
,
126 "infrun: infrun_async(%d)\n",
130 mark_async_event_handler (infrun_async_inferior_event_token
);
132 clear_async_event_handler (infrun_async_inferior_event_token
);
139 mark_infrun_async_event_handler (void)
141 mark_async_event_handler (infrun_async_inferior_event_token
);
144 /* When set, stop the 'step' command if we enter a function which has
145 no line number information. The normal behavior is that we step
146 over such function. */
147 int step_stop_if_no_debug
= 0;
149 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
150 struct cmd_list_element
*c
, const char *value
)
152 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
155 /* proceed and normal_stop use this to notify the user when the
156 inferior stopped in a different thread than it had been running
159 static ptid_t previous_inferior_ptid
;
161 /* If set (default for legacy reasons), when following a fork, GDB
162 will detach from one of the fork branches, child or parent.
163 Exactly which branch is detached depends on 'set follow-fork-mode'
166 static int detach_fork
= 1;
168 int debug_displaced
= 0;
170 show_debug_displaced (struct ui_file
*file
, int from_tty
,
171 struct cmd_list_element
*c
, const char *value
)
173 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
176 unsigned int debug_infrun
= 0;
178 show_debug_infrun (struct ui_file
*file
, int from_tty
,
179 struct cmd_list_element
*c
, const char *value
)
181 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
185 /* Support for disabling address space randomization. */
187 int disable_randomization
= 1;
190 show_disable_randomization (struct ui_file
*file
, int from_tty
,
191 struct cmd_list_element
*c
, const char *value
)
193 if (target_supports_disable_randomization ())
194 fprintf_filtered (file
,
195 _("Disabling randomization of debuggee's "
196 "virtual address space is %s.\n"),
199 fputs_filtered (_("Disabling randomization of debuggee's "
200 "virtual address space is unsupported on\n"
201 "this platform.\n"), file
);
205 set_disable_randomization (char *args
, int from_tty
,
206 struct cmd_list_element
*c
)
208 if (!target_supports_disable_randomization ())
209 error (_("Disabling randomization of debuggee's "
210 "virtual address space is unsupported on\n"
214 /* User interface for non-stop mode. */
217 static int non_stop_1
= 0;
220 set_non_stop (char *args
, int from_tty
,
221 struct cmd_list_element
*c
)
223 if (target_has_execution
)
225 non_stop_1
= non_stop
;
226 error (_("Cannot change this setting while the inferior is running."));
229 non_stop
= non_stop_1
;
233 show_non_stop (struct ui_file
*file
, int from_tty
,
234 struct cmd_list_element
*c
, const char *value
)
236 fprintf_filtered (file
,
237 _("Controlling the inferior in non-stop mode is %s.\n"),
241 /* "Observer mode" is somewhat like a more extreme version of
242 non-stop, in which all GDB operations that might affect the
243 target's execution have been disabled. */
245 int observer_mode
= 0;
246 static int observer_mode_1
= 0;
249 set_observer_mode (char *args
, int from_tty
,
250 struct cmd_list_element
*c
)
252 if (target_has_execution
)
254 observer_mode_1
= observer_mode
;
255 error (_("Cannot change this setting while the inferior is running."));
258 observer_mode
= observer_mode_1
;
260 may_write_registers
= !observer_mode
;
261 may_write_memory
= !observer_mode
;
262 may_insert_breakpoints
= !observer_mode
;
263 may_insert_tracepoints
= !observer_mode
;
264 /* We can insert fast tracepoints in or out of observer mode,
265 but enable them if we're going into this mode. */
267 may_insert_fast_tracepoints
= 1;
268 may_stop
= !observer_mode
;
269 update_target_permissions ();
271 /* Going *into* observer mode we must force non-stop, then
272 going out we leave it that way. */
275 pagination_enabled
= 0;
276 non_stop
= non_stop_1
= 1;
280 printf_filtered (_("Observer mode is now %s.\n"),
281 (observer_mode
? "on" : "off"));
285 show_observer_mode (struct ui_file
*file
, int from_tty
,
286 struct cmd_list_element
*c
, const char *value
)
288 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
291 /* This updates the value of observer mode based on changes in
292 permissions. Note that we are deliberately ignoring the values of
293 may-write-registers and may-write-memory, since the user may have
294 reason to enable these during a session, for instance to turn on a
295 debugging-related global. */
298 update_observer_mode (void)
302 newval
= (!may_insert_breakpoints
303 && !may_insert_tracepoints
304 && may_insert_fast_tracepoints
308 /* Let the user know if things change. */
309 if (newval
!= observer_mode
)
310 printf_filtered (_("Observer mode is now %s.\n"),
311 (newval
? "on" : "off"));
313 observer_mode
= observer_mode_1
= newval
;
316 /* Tables of how to react to signals; the user sets them. */
318 static unsigned char *signal_stop
;
319 static unsigned char *signal_print
;
320 static unsigned char *signal_program
;
322 /* Table of signals that are registered with "catch signal". A
323 non-zero entry indicates that the signal is caught by some "catch
324 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
326 static unsigned char *signal_catch
;
328 /* Table of signals that the target may silently handle.
329 This is automatically determined from the flags above,
330 and simply cached here. */
331 static unsigned char *signal_pass
;
333 #define SET_SIGS(nsigs,sigs,flags) \
335 int signum = (nsigs); \
336 while (signum-- > 0) \
337 if ((sigs)[signum]) \
338 (flags)[signum] = 1; \
341 #define UNSET_SIGS(nsigs,sigs,flags) \
343 int signum = (nsigs); \
344 while (signum-- > 0) \
345 if ((sigs)[signum]) \
346 (flags)[signum] = 0; \
349 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
350 this function is to avoid exporting `signal_program'. */
353 update_signals_program_target (void)
355 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
358 /* Value to pass to target_resume() to cause all threads to resume. */
360 #define RESUME_ALL minus_one_ptid
362 /* Command list pointer for the "stop" placeholder. */
364 static struct cmd_list_element
*stop_command
;
366 /* Nonzero if we want to give control to the user when we're notified
367 of shared library events by the dynamic linker. */
368 int stop_on_solib_events
;
370 /* Enable or disable optional shared library event breakpoints
371 as appropriate when the above flag is changed. */
374 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
376 update_solib_breakpoints ();
380 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
381 struct cmd_list_element
*c
, const char *value
)
383 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
387 /* Nonzero after stop if current stack frame should be printed. */
389 static int stop_print_frame
;
391 /* This is a cached copy of the pid/waitstatus of the last event
392 returned by target_wait()/deprecated_target_wait_hook(). This
393 information is returned by get_last_target_status(). */
394 static ptid_t target_last_wait_ptid
;
395 static struct target_waitstatus target_last_waitstatus
;
397 static void context_switch (ptid_t ptid
);
399 void init_thread_stepping_state (struct thread_info
*tss
);
401 static const char follow_fork_mode_child
[] = "child";
402 static const char follow_fork_mode_parent
[] = "parent";
404 static const char *const follow_fork_mode_kind_names
[] = {
405 follow_fork_mode_child
,
406 follow_fork_mode_parent
,
410 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
412 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
413 struct cmd_list_element
*c
, const char *value
)
415 fprintf_filtered (file
,
416 _("Debugger response to a program "
417 "call of fork or vfork is \"%s\".\n"),
422 /* Handle changes to the inferior list based on the type of fork,
423 which process is being followed, and whether the other process
424 should be detached. On entry inferior_ptid must be the ptid of
425 the fork parent. At return inferior_ptid is the ptid of the
426 followed inferior. */
429 follow_fork_inferior (int follow_child
, int detach_fork
)
432 ptid_t parent_ptid
, child_ptid
;
434 has_vforked
= (inferior_thread ()->pending_follow
.kind
435 == TARGET_WAITKIND_VFORKED
);
436 parent_ptid
= inferior_ptid
;
437 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
440 && !non_stop
/* Non-stop always resumes both branches. */
441 && current_ui
->prompt_state
== PROMPT_BLOCKED
442 && !(follow_child
|| detach_fork
|| sched_multi
))
444 /* The parent stays blocked inside the vfork syscall until the
445 child execs or exits. If we don't let the child run, then
446 the parent stays blocked. If we're telling the parent to run
447 in the foreground, the user will not be able to ctrl-c to get
448 back the terminal, effectively hanging the debug session. */
449 fprintf_filtered (gdb_stderr
, _("\
450 Can not resume the parent process over vfork in the foreground while\n\
451 holding the child stopped. Try \"set detach-on-fork\" or \
452 \"set schedule-multiple\".\n"));
453 /* FIXME output string > 80 columns. */
459 /* Detach new forked process? */
462 /* Before detaching from the child, remove all breakpoints
463 from it. If we forked, then this has already been taken
464 care of by infrun.c. If we vforked however, any
465 breakpoint inserted in the parent is visible in the
466 child, even those added while stopped in a vfork
467 catchpoint. This will remove the breakpoints from the
468 parent also, but they'll be reinserted below. */
471 /* Keep breakpoints list in sync. */
472 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
475 if (info_verbose
|| debug_infrun
)
477 /* Ensure that we have a process ptid. */
478 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
480 target_terminal_ours_for_output ();
481 fprintf_filtered (gdb_stdlog
,
482 _("Detaching after %s from child %s.\n"),
483 has_vforked
? "vfork" : "fork",
484 target_pid_to_str (process_ptid
));
489 struct inferior
*parent_inf
, *child_inf
;
490 struct cleanup
*old_chain
;
492 /* Add process to GDB's tables. */
493 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
495 parent_inf
= current_inferior ();
496 child_inf
->attach_flag
= parent_inf
->attach_flag
;
497 copy_terminal_info (child_inf
, parent_inf
);
498 child_inf
->gdbarch
= parent_inf
->gdbarch
;
499 copy_inferior_target_desc_info (child_inf
, parent_inf
);
501 old_chain
= save_inferior_ptid ();
502 save_current_program_space ();
504 inferior_ptid
= child_ptid
;
505 add_thread (inferior_ptid
);
506 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
508 /* If this is a vfork child, then the address-space is
509 shared with the parent. */
512 child_inf
->pspace
= parent_inf
->pspace
;
513 child_inf
->aspace
= parent_inf
->aspace
;
515 /* The parent will be frozen until the child is done
516 with the shared region. Keep track of the
518 child_inf
->vfork_parent
= parent_inf
;
519 child_inf
->pending_detach
= 0;
520 parent_inf
->vfork_child
= child_inf
;
521 parent_inf
->pending_detach
= 0;
525 child_inf
->aspace
= new_address_space ();
526 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
527 child_inf
->removable
= 1;
528 set_current_program_space (child_inf
->pspace
);
529 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
531 /* Let the shared library layer (e.g., solib-svr4) learn
532 about this new process, relocate the cloned exec, pull
533 in shared libraries, and install the solib event
534 breakpoint. If a "cloned-VM" event was propagated
535 better throughout the core, this wouldn't be
537 solib_create_inferior_hook (0);
540 do_cleanups (old_chain
);
545 struct inferior
*parent_inf
;
547 parent_inf
= current_inferior ();
549 /* If we detached from the child, then we have to be careful
550 to not insert breakpoints in the parent until the child
551 is done with the shared memory region. However, if we're
552 staying attached to the child, then we can and should
553 insert breakpoints, so that we can debug it. A
554 subsequent child exec or exit is enough to know when does
555 the child stops using the parent's address space. */
556 parent_inf
->waiting_for_vfork_done
= detach_fork
;
557 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
562 /* Follow the child. */
563 struct inferior
*parent_inf
, *child_inf
;
564 struct program_space
*parent_pspace
;
566 if (info_verbose
|| debug_infrun
)
568 target_terminal_ours_for_output ();
569 fprintf_filtered (gdb_stdlog
,
570 _("Attaching after %s %s to child %s.\n"),
571 target_pid_to_str (parent_ptid
),
572 has_vforked
? "vfork" : "fork",
573 target_pid_to_str (child_ptid
));
576 /* Add the new inferior first, so that the target_detach below
577 doesn't unpush the target. */
579 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
581 parent_inf
= current_inferior ();
582 child_inf
->attach_flag
= parent_inf
->attach_flag
;
583 copy_terminal_info (child_inf
, parent_inf
);
584 child_inf
->gdbarch
= parent_inf
->gdbarch
;
585 copy_inferior_target_desc_info (child_inf
, parent_inf
);
587 parent_pspace
= parent_inf
->pspace
;
589 /* If we're vforking, we want to hold on to the parent until the
590 child exits or execs. At child exec or exit time we can
591 remove the old breakpoints from the parent and detach or
592 resume debugging it. Otherwise, detach the parent now; we'll
593 want to reuse it's program/address spaces, but we can't set
594 them to the child before removing breakpoints from the
595 parent, otherwise, the breakpoints module could decide to
596 remove breakpoints from the wrong process (since they'd be
597 assigned to the same address space). */
601 gdb_assert (child_inf
->vfork_parent
== NULL
);
602 gdb_assert (parent_inf
->vfork_child
== NULL
);
603 child_inf
->vfork_parent
= parent_inf
;
604 child_inf
->pending_detach
= 0;
605 parent_inf
->vfork_child
= child_inf
;
606 parent_inf
->pending_detach
= detach_fork
;
607 parent_inf
->waiting_for_vfork_done
= 0;
609 else if (detach_fork
)
611 if (info_verbose
|| debug_infrun
)
613 /* Ensure that we have a process ptid. */
614 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
616 target_terminal_ours_for_output ();
617 fprintf_filtered (gdb_stdlog
,
618 _("Detaching after fork from "
620 target_pid_to_str (process_ptid
));
623 target_detach (NULL
, 0);
626 /* Note that the detach above makes PARENT_INF dangling. */
628 /* Add the child thread to the appropriate lists, and switch to
629 this new thread, before cloning the program space, and
630 informing the solib layer about this new process. */
632 inferior_ptid
= child_ptid
;
633 add_thread (inferior_ptid
);
635 /* If this is a vfork child, then the address-space is shared
636 with the parent. If we detached from the parent, then we can
637 reuse the parent's program/address spaces. */
638 if (has_vforked
|| detach_fork
)
640 child_inf
->pspace
= parent_pspace
;
641 child_inf
->aspace
= child_inf
->pspace
->aspace
;
645 child_inf
->aspace
= new_address_space ();
646 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
647 child_inf
->removable
= 1;
648 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
649 set_current_program_space (child_inf
->pspace
);
650 clone_program_space (child_inf
->pspace
, parent_pspace
);
652 /* Let the shared library layer (e.g., solib-svr4) learn
653 about this new process, relocate the cloned exec, pull in
654 shared libraries, and install the solib event breakpoint.
655 If a "cloned-VM" event was propagated better throughout
656 the core, this wouldn't be required. */
657 solib_create_inferior_hook (0);
661 return target_follow_fork (follow_child
, detach_fork
);
664 /* Tell the target to follow the fork we're stopped at. Returns true
665 if the inferior should be resumed; false, if the target for some
666 reason decided it's best not to resume. */
671 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
672 int should_resume
= 1;
673 struct thread_info
*tp
;
675 /* Copy user stepping state to the new inferior thread. FIXME: the
676 followed fork child thread should have a copy of most of the
677 parent thread structure's run control related fields, not just these.
678 Initialized to avoid "may be used uninitialized" warnings from gcc. */
679 struct breakpoint
*step_resume_breakpoint
= NULL
;
680 struct breakpoint
*exception_resume_breakpoint
= NULL
;
681 CORE_ADDR step_range_start
= 0;
682 CORE_ADDR step_range_end
= 0;
683 struct frame_id step_frame_id
= { 0 };
684 struct interp
*command_interp
= NULL
;
689 struct target_waitstatus wait_status
;
691 /* Get the last target status returned by target_wait(). */
692 get_last_target_status (&wait_ptid
, &wait_status
);
694 /* If not stopped at a fork event, then there's nothing else to
696 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
697 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
700 /* Check if we switched over from WAIT_PTID, since the event was
702 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
703 && !ptid_equal (inferior_ptid
, wait_ptid
))
705 /* We did. Switch back to WAIT_PTID thread, to tell the
706 target to follow it (in either direction). We'll
707 afterwards refuse to resume, and inform the user what
709 switch_to_thread (wait_ptid
);
714 tp
= inferior_thread ();
716 /* If there were any forks/vforks that were caught and are now to be
717 followed, then do so now. */
718 switch (tp
->pending_follow
.kind
)
720 case TARGET_WAITKIND_FORKED
:
721 case TARGET_WAITKIND_VFORKED
:
723 ptid_t parent
, child
;
725 /* If the user did a next/step, etc, over a fork call,
726 preserve the stepping state in the fork child. */
727 if (follow_child
&& should_resume
)
729 step_resume_breakpoint
= clone_momentary_breakpoint
730 (tp
->control
.step_resume_breakpoint
);
731 step_range_start
= tp
->control
.step_range_start
;
732 step_range_end
= tp
->control
.step_range_end
;
733 step_frame_id
= tp
->control
.step_frame_id
;
734 exception_resume_breakpoint
735 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
736 command_interp
= tp
->control
.command_interp
;
738 /* For now, delete the parent's sr breakpoint, otherwise,
739 parent/child sr breakpoints are considered duplicates,
740 and the child version will not be installed. Remove
741 this when the breakpoints module becomes aware of
742 inferiors and address spaces. */
743 delete_step_resume_breakpoint (tp
);
744 tp
->control
.step_range_start
= 0;
745 tp
->control
.step_range_end
= 0;
746 tp
->control
.step_frame_id
= null_frame_id
;
747 delete_exception_resume_breakpoint (tp
);
748 tp
->control
.command_interp
= NULL
;
751 parent
= inferior_ptid
;
752 child
= tp
->pending_follow
.value
.related_pid
;
754 /* Set up inferior(s) as specified by the caller, and tell the
755 target to do whatever is necessary to follow either parent
757 if (follow_fork_inferior (follow_child
, detach_fork
))
759 /* Target refused to follow, or there's some other reason
760 we shouldn't resume. */
765 /* This pending follow fork event is now handled, one way
766 or another. The previous selected thread may be gone
767 from the lists by now, but if it is still around, need
768 to clear the pending follow request. */
769 tp
= find_thread_ptid (parent
);
771 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
773 /* This makes sure we don't try to apply the "Switched
774 over from WAIT_PID" logic above. */
775 nullify_last_target_wait_ptid ();
777 /* If we followed the child, switch to it... */
780 switch_to_thread (child
);
782 /* ... and preserve the stepping state, in case the
783 user was stepping over the fork call. */
786 tp
= inferior_thread ();
787 tp
->control
.step_resume_breakpoint
788 = step_resume_breakpoint
;
789 tp
->control
.step_range_start
= step_range_start
;
790 tp
->control
.step_range_end
= step_range_end
;
791 tp
->control
.step_frame_id
= step_frame_id
;
792 tp
->control
.exception_resume_breakpoint
793 = exception_resume_breakpoint
;
794 tp
->control
.command_interp
= command_interp
;
798 /* If we get here, it was because we're trying to
799 resume from a fork catchpoint, but, the user
800 has switched threads away from the thread that
801 forked. In that case, the resume command
802 issued is most likely not applicable to the
803 child, so just warn, and refuse to resume. */
804 warning (_("Not resuming: switched threads "
805 "before following fork child."));
808 /* Reset breakpoints in the child as appropriate. */
809 follow_inferior_reset_breakpoints ();
812 switch_to_thread (parent
);
816 case TARGET_WAITKIND_SPURIOUS
:
817 /* Nothing to follow. */
820 internal_error (__FILE__
, __LINE__
,
821 "Unexpected pending_follow.kind %d\n",
822 tp
->pending_follow
.kind
);
826 return should_resume
;
830 follow_inferior_reset_breakpoints (void)
832 struct thread_info
*tp
= inferior_thread ();
834 /* Was there a step_resume breakpoint? (There was if the user
835 did a "next" at the fork() call.) If so, explicitly reset its
836 thread number. Cloned step_resume breakpoints are disabled on
837 creation, so enable it here now that it is associated with the
840 step_resumes are a form of bp that are made to be per-thread.
841 Since we created the step_resume bp when the parent process
842 was being debugged, and now are switching to the child process,
843 from the breakpoint package's viewpoint, that's a switch of
844 "threads". We must update the bp's notion of which thread
845 it is for, or it'll be ignored when it triggers. */
847 if (tp
->control
.step_resume_breakpoint
)
849 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
850 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
853 /* Treat exception_resume breakpoints like step_resume breakpoints. */
854 if (tp
->control
.exception_resume_breakpoint
)
856 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
857 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
860 /* Reinsert all breakpoints in the child. The user may have set
861 breakpoints after catching the fork, in which case those
862 were never set in the child, but only in the parent. This makes
863 sure the inserted breakpoints match the breakpoint list. */
865 breakpoint_re_set ();
866 insert_breakpoints ();
869 /* The child has exited or execed: resume threads of the parent the
870 user wanted to be executing. */
873 proceed_after_vfork_done (struct thread_info
*thread
,
876 int pid
= * (int *) arg
;
878 if (ptid_get_pid (thread
->ptid
) == pid
879 && is_running (thread
->ptid
)
880 && !is_executing (thread
->ptid
)
881 && !thread
->stop_requested
882 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
885 fprintf_unfiltered (gdb_stdlog
,
886 "infrun: resuming vfork parent thread %s\n",
887 target_pid_to_str (thread
->ptid
));
889 switch_to_thread (thread
->ptid
);
890 clear_proceed_status (0);
891 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
897 /* Called whenever we notice an exec or exit event, to handle
898 detaching or resuming a vfork parent. */
901 handle_vfork_child_exec_or_exit (int exec
)
903 struct inferior
*inf
= current_inferior ();
905 if (inf
->vfork_parent
)
907 int resume_parent
= -1;
909 /* This exec or exit marks the end of the shared memory region
910 between the parent and the child. If the user wanted to
911 detach from the parent, now is the time. */
913 if (inf
->vfork_parent
->pending_detach
)
915 struct thread_info
*tp
;
916 struct cleanup
*old_chain
;
917 struct program_space
*pspace
;
918 struct address_space
*aspace
;
920 /* follow-fork child, detach-on-fork on. */
922 inf
->vfork_parent
->pending_detach
= 0;
926 /* If we're handling a child exit, then inferior_ptid
927 points at the inferior's pid, not to a thread. */
928 old_chain
= save_inferior_ptid ();
929 save_current_program_space ();
930 save_current_inferior ();
933 old_chain
= save_current_space_and_thread ();
935 /* We're letting loose of the parent. */
936 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
937 switch_to_thread (tp
->ptid
);
939 /* We're about to detach from the parent, which implicitly
940 removes breakpoints from its address space. There's a
941 catch here: we want to reuse the spaces for the child,
942 but, parent/child are still sharing the pspace at this
943 point, although the exec in reality makes the kernel give
944 the child a fresh set of new pages. The problem here is
945 that the breakpoints module being unaware of this, would
946 likely chose the child process to write to the parent
947 address space. Swapping the child temporarily away from
948 the spaces has the desired effect. Yes, this is "sort
951 pspace
= inf
->pspace
;
952 aspace
= inf
->aspace
;
956 if (debug_infrun
|| info_verbose
)
958 target_terminal_ours_for_output ();
962 fprintf_filtered (gdb_stdlog
,
963 _("Detaching vfork parent process "
964 "%d after child exec.\n"),
965 inf
->vfork_parent
->pid
);
969 fprintf_filtered (gdb_stdlog
,
970 _("Detaching vfork parent process "
971 "%d after child exit.\n"),
972 inf
->vfork_parent
->pid
);
976 target_detach (NULL
, 0);
979 inf
->pspace
= pspace
;
980 inf
->aspace
= aspace
;
982 do_cleanups (old_chain
);
986 /* We're staying attached to the parent, so, really give the
987 child a new address space. */
988 inf
->pspace
= add_program_space (maybe_new_address_space ());
989 inf
->aspace
= inf
->pspace
->aspace
;
991 set_current_program_space (inf
->pspace
);
993 resume_parent
= inf
->vfork_parent
->pid
;
995 /* Break the bonds. */
996 inf
->vfork_parent
->vfork_child
= NULL
;
1000 struct cleanup
*old_chain
;
1001 struct program_space
*pspace
;
1003 /* If this is a vfork child exiting, then the pspace and
1004 aspaces were shared with the parent. Since we're
1005 reporting the process exit, we'll be mourning all that is
1006 found in the address space, and switching to null_ptid,
1007 preparing to start a new inferior. But, since we don't
1008 want to clobber the parent's address/program spaces, we
1009 go ahead and create a new one for this exiting
1012 /* Switch to null_ptid, so that clone_program_space doesn't want
1013 to read the selected frame of a dead process. */
1014 old_chain
= save_inferior_ptid ();
1015 inferior_ptid
= null_ptid
;
1017 /* This inferior is dead, so avoid giving the breakpoints
1018 module the option to write through to it (cloning a
1019 program space resets breakpoints). */
1022 pspace
= add_program_space (maybe_new_address_space ());
1023 set_current_program_space (pspace
);
1025 inf
->symfile_flags
= SYMFILE_NO_READ
;
1026 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1027 inf
->pspace
= pspace
;
1028 inf
->aspace
= pspace
->aspace
;
1030 /* Put back inferior_ptid. We'll continue mourning this
1032 do_cleanups (old_chain
);
1034 resume_parent
= inf
->vfork_parent
->pid
;
1035 /* Break the bonds. */
1036 inf
->vfork_parent
->vfork_child
= NULL
;
1039 inf
->vfork_parent
= NULL
;
1041 gdb_assert (current_program_space
== inf
->pspace
);
1043 if (non_stop
&& resume_parent
!= -1)
1045 /* If the user wanted the parent to be running, let it go
1047 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1050 fprintf_unfiltered (gdb_stdlog
,
1051 "infrun: resuming vfork parent process %d\n",
1054 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1056 do_cleanups (old_chain
);
1061 /* Enum strings for "set|show follow-exec-mode". */
1063 static const char follow_exec_mode_new
[] = "new";
1064 static const char follow_exec_mode_same
[] = "same";
1065 static const char *const follow_exec_mode_names
[] =
1067 follow_exec_mode_new
,
1068 follow_exec_mode_same
,
1072 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1074 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1075 struct cmd_list_element
*c
, const char *value
)
1077 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1080 /* EXECD_PATHNAME is assumed to be non-NULL. */
1083 follow_exec (ptid_t ptid
, char *execd_pathname
)
1085 struct thread_info
*th
, *tmp
;
1086 struct inferior
*inf
= current_inferior ();
1087 int pid
= ptid_get_pid (ptid
);
1088 ptid_t process_ptid
;
1090 /* This is an exec event that we actually wish to pay attention to.
1091 Refresh our symbol table to the newly exec'd program, remove any
1092 momentary bp's, etc.
1094 If there are breakpoints, they aren't really inserted now,
1095 since the exec() transformed our inferior into a fresh set
1098 We want to preserve symbolic breakpoints on the list, since
1099 we have hopes that they can be reset after the new a.out's
1100 symbol table is read.
1102 However, any "raw" breakpoints must be removed from the list
1103 (e.g., the solib bp's), since their address is probably invalid
1106 And, we DON'T want to call delete_breakpoints() here, since
1107 that may write the bp's "shadow contents" (the instruction
1108 value that was overwritten witha TRAP instruction). Since
1109 we now have a new a.out, those shadow contents aren't valid. */
1111 mark_breakpoints_out ();
1113 /* The target reports the exec event to the main thread, even if
1114 some other thread does the exec, and even if the main thread was
1115 stopped or already gone. We may still have non-leader threads of
1116 the process on our list. E.g., on targets that don't have thread
1117 exit events (like remote); or on native Linux in non-stop mode if
1118 there were only two threads in the inferior and the non-leader
1119 one is the one that execs (and nothing forces an update of the
1120 thread list up to here). When debugging remotely, it's best to
1121 avoid extra traffic, when possible, so avoid syncing the thread
1122 list with the target, and instead go ahead and delete all threads
1123 of the process but one that reported the event. Note this must
1124 be done before calling update_breakpoints_after_exec, as
1125 otherwise clearing the threads' resources would reference stale
1126 thread breakpoints -- it may have been one of these threads that
1127 stepped across the exec. We could just clear their stepping
1128 states, but as long as we're iterating, might as well delete
1129 them. Deleting them now rather than at the next user-visible
1130 stop provides a nicer sequence of events for user and MI
1132 ALL_THREADS_SAFE (th
, tmp
)
1133 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1134 delete_thread (th
->ptid
);
1136 /* We also need to clear any left over stale state for the
1137 leader/event thread. E.g., if there was any step-resume
1138 breakpoint or similar, it's gone now. We cannot truly
1139 step-to-next statement through an exec(). */
1140 th
= inferior_thread ();
1141 th
->control
.step_resume_breakpoint
= NULL
;
1142 th
->control
.exception_resume_breakpoint
= NULL
;
1143 th
->control
.single_step_breakpoints
= NULL
;
1144 th
->control
.step_range_start
= 0;
1145 th
->control
.step_range_end
= 0;
1147 /* The user may have had the main thread held stopped in the
1148 previous image (e.g., schedlock on, or non-stop). Release
1150 th
->stop_requested
= 0;
1152 update_breakpoints_after_exec ();
1154 /* What is this a.out's name? */
1155 process_ptid
= pid_to_ptid (pid
);
1156 printf_unfiltered (_("%s is executing new program: %s\n"),
1157 target_pid_to_str (process_ptid
),
1160 /* We've followed the inferior through an exec. Therefore, the
1161 inferior has essentially been killed & reborn. */
1163 gdb_flush (gdb_stdout
);
1165 breakpoint_init_inferior (inf_execd
);
1167 if (*gdb_sysroot
!= '\0')
1169 char *name
= exec_file_find (execd_pathname
, NULL
);
1171 execd_pathname
= (char *) alloca (strlen (name
) + 1);
1172 strcpy (execd_pathname
, name
);
1176 /* Reset the shared library package. This ensures that we get a
1177 shlib event when the child reaches "_start", at which point the
1178 dld will have had a chance to initialize the child. */
1179 /* Also, loading a symbol file below may trigger symbol lookups, and
1180 we don't want those to be satisfied by the libraries of the
1181 previous incarnation of this process. */
1182 no_shared_libraries (NULL
, 0);
1184 if (follow_exec_mode_string
== follow_exec_mode_new
)
1186 /* The user wants to keep the old inferior and program spaces
1187 around. Create a new fresh one, and switch to it. */
1189 /* Do exit processing for the original inferior before adding
1190 the new inferior so we don't have two active inferiors with
1191 the same ptid, which can confuse find_inferior_ptid. */
1192 exit_inferior_num_silent (current_inferior ()->num
);
1194 inf
= add_inferior_with_spaces ();
1196 target_follow_exec (inf
, execd_pathname
);
1198 set_current_inferior (inf
);
1199 set_current_program_space (inf
->pspace
);
1204 /* The old description may no longer be fit for the new image.
1205 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1206 old description; we'll read a new one below. No need to do
1207 this on "follow-exec-mode new", as the old inferior stays
1208 around (its description is later cleared/refetched on
1210 target_clear_description ();
1213 gdb_assert (current_program_space
== inf
->pspace
);
1215 /* That a.out is now the one to use. */
1216 exec_file_attach (execd_pathname
, 0);
1218 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1219 (Position Independent Executable) main symbol file will get applied by
1220 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1221 the breakpoints with the zero displacement. */
1223 symbol_file_add (execd_pathname
,
1225 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
1228 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
1229 set_initial_language ();
1231 /* If the target can specify a description, read it. Must do this
1232 after flipping to the new executable (because the target supplied
1233 description must be compatible with the executable's
1234 architecture, and the old executable may e.g., be 32-bit, while
1235 the new one 64-bit), and before anything involving memory or
1237 target_find_description ();
1239 solib_create_inferior_hook (0);
1241 jit_inferior_created_hook ();
1243 breakpoint_re_set ();
1245 /* Reinsert all breakpoints. (Those which were symbolic have
1246 been reset to the proper address in the new a.out, thanks
1247 to symbol_file_command...). */
1248 insert_breakpoints ();
1250 /* The next resume of this inferior should bring it to the shlib
1251 startup breakpoints. (If the user had also set bp's on
1252 "main" from the old (parent) process, then they'll auto-
1253 matically get reset there in the new process.). */
1256 /* The queue of threads that need to do a step-over operation to get
1257 past e.g., a breakpoint. What technique is used to step over the
1258 breakpoint/watchpoint does not matter -- all threads end up in the
1259 same queue, to maintain rough temporal order of execution, in order
1260 to avoid starvation, otherwise, we could e.g., find ourselves
1261 constantly stepping the same couple threads past their breakpoints
1262 over and over, if the single-step finish fast enough. */
1263 struct thread_info
*step_over_queue_head
;
1265 /* Bit flags indicating what the thread needs to step over. */
1267 enum step_over_what_flag
1269 /* Step over a breakpoint. */
1270 STEP_OVER_BREAKPOINT
= 1,
1272 /* Step past a non-continuable watchpoint, in order to let the
1273 instruction execute so we can evaluate the watchpoint
1275 STEP_OVER_WATCHPOINT
= 2
1277 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1279 /* Info about an instruction that is being stepped over. */
1281 struct step_over_info
1283 /* If we're stepping past a breakpoint, this is the address space
1284 and address of the instruction the breakpoint is set at. We'll
1285 skip inserting all breakpoints here. Valid iff ASPACE is
1287 struct address_space
*aspace
;
1290 /* The instruction being stepped over triggers a nonsteppable
1291 watchpoint. If true, we'll skip inserting watchpoints. */
1292 int nonsteppable_watchpoint_p
;
1294 /* The thread's global number. */
1298 /* The step-over info of the location that is being stepped over.
1300 Note that with async/breakpoint always-inserted mode, a user might
1301 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1302 being stepped over. As setting a new breakpoint inserts all
1303 breakpoints, we need to make sure the breakpoint being stepped over
1304 isn't inserted then. We do that by only clearing the step-over
1305 info when the step-over is actually finished (or aborted).
1307 Presently GDB can only step over one breakpoint at any given time.
1308 Given threads that can't run code in the same address space as the
1309 breakpoint's can't really miss the breakpoint, GDB could be taught
1310 to step-over at most one breakpoint per address space (so this info
1311 could move to the address space object if/when GDB is extended).
1312 The set of breakpoints being stepped over will normally be much
1313 smaller than the set of all breakpoints, so a flag in the
1314 breakpoint location structure would be wasteful. A separate list
1315 also saves complexity and run-time, as otherwise we'd have to go
1316 through all breakpoint locations clearing their flag whenever we
1317 start a new sequence. Similar considerations weigh against storing
1318 this info in the thread object. Plus, not all step overs actually
1319 have breakpoint locations -- e.g., stepping past a single-step
1320 breakpoint, or stepping to complete a non-continuable
1322 static struct step_over_info step_over_info
;
1324 /* Record the address of the breakpoint/instruction we're currently
1328 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1329 int nonsteppable_watchpoint_p
,
1332 step_over_info
.aspace
= aspace
;
1333 step_over_info
.address
= address
;
1334 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1335 step_over_info
.thread
= thread
;
1338 /* Called when we're not longer stepping over a breakpoint / an
1339 instruction, so all breakpoints are free to be (re)inserted. */
1342 clear_step_over_info (void)
1345 fprintf_unfiltered (gdb_stdlog
,
1346 "infrun: clear_step_over_info\n");
1347 step_over_info
.aspace
= NULL
;
1348 step_over_info
.address
= 0;
1349 step_over_info
.nonsteppable_watchpoint_p
= 0;
1350 step_over_info
.thread
= -1;
1356 stepping_past_instruction_at (struct address_space
*aspace
,
1359 return (step_over_info
.aspace
!= NULL
1360 && breakpoint_address_match (aspace
, address
,
1361 step_over_info
.aspace
,
1362 step_over_info
.address
));
1368 thread_is_stepping_over_breakpoint (int thread
)
1370 return (step_over_info
.thread
!= -1
1371 && thread
== step_over_info
.thread
);
1377 stepping_past_nonsteppable_watchpoint (void)
1379 return step_over_info
.nonsteppable_watchpoint_p
;
1382 /* Returns true if step-over info is valid. */
1385 step_over_info_valid_p (void)
1387 return (step_over_info
.aspace
!= NULL
1388 || stepping_past_nonsteppable_watchpoint ());
1392 /* Displaced stepping. */
1394 /* In non-stop debugging mode, we must take special care to manage
1395 breakpoints properly; in particular, the traditional strategy for
1396 stepping a thread past a breakpoint it has hit is unsuitable.
1397 'Displaced stepping' is a tactic for stepping one thread past a
1398 breakpoint it has hit while ensuring that other threads running
1399 concurrently will hit the breakpoint as they should.
1401 The traditional way to step a thread T off a breakpoint in a
1402 multi-threaded program in all-stop mode is as follows:
1404 a0) Initially, all threads are stopped, and breakpoints are not
1406 a1) We single-step T, leaving breakpoints uninserted.
1407 a2) We insert breakpoints, and resume all threads.
1409 In non-stop debugging, however, this strategy is unsuitable: we
1410 don't want to have to stop all threads in the system in order to
1411 continue or step T past a breakpoint. Instead, we use displaced
1414 n0) Initially, T is stopped, other threads are running, and
1415 breakpoints are inserted.
1416 n1) We copy the instruction "under" the breakpoint to a separate
1417 location, outside the main code stream, making any adjustments
1418 to the instruction, register, and memory state as directed by
1420 n2) We single-step T over the instruction at its new location.
1421 n3) We adjust the resulting register and memory state as directed
1422 by T's architecture. This includes resetting T's PC to point
1423 back into the main instruction stream.
1426 This approach depends on the following gdbarch methods:
1428 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1429 indicate where to copy the instruction, and how much space must
1430 be reserved there. We use these in step n1.
1432 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1433 address, and makes any necessary adjustments to the instruction,
1434 register contents, and memory. We use this in step n1.
1436 - gdbarch_displaced_step_fixup adjusts registers and memory after
1437 we have successfuly single-stepped the instruction, to yield the
1438 same effect the instruction would have had if we had executed it
1439 at its original address. We use this in step n3.
1441 - gdbarch_displaced_step_free_closure provides cleanup.
1443 The gdbarch_displaced_step_copy_insn and
1444 gdbarch_displaced_step_fixup functions must be written so that
1445 copying an instruction with gdbarch_displaced_step_copy_insn,
1446 single-stepping across the copied instruction, and then applying
1447 gdbarch_displaced_insn_fixup should have the same effects on the
1448 thread's memory and registers as stepping the instruction in place
1449 would have. Exactly which responsibilities fall to the copy and
1450 which fall to the fixup is up to the author of those functions.
1452 See the comments in gdbarch.sh for details.
1454 Note that displaced stepping and software single-step cannot
1455 currently be used in combination, although with some care I think
1456 they could be made to. Software single-step works by placing
1457 breakpoints on all possible subsequent instructions; if the
1458 displaced instruction is a PC-relative jump, those breakpoints
1459 could fall in very strange places --- on pages that aren't
1460 executable, or at addresses that are not proper instruction
1461 boundaries. (We do generally let other threads run while we wait
1462 to hit the software single-step breakpoint, and they might
1463 encounter such a corrupted instruction.) One way to work around
1464 this would be to have gdbarch_displaced_step_copy_insn fully
1465 simulate the effect of PC-relative instructions (and return NULL)
1466 on architectures that use software single-stepping.
1468 In non-stop mode, we can have independent and simultaneous step
1469 requests, so more than one thread may need to simultaneously step
1470 over a breakpoint. The current implementation assumes there is
1471 only one scratch space per process. In this case, we have to
1472 serialize access to the scratch space. If thread A wants to step
1473 over a breakpoint, but we are currently waiting for some other
1474 thread to complete a displaced step, we leave thread A stopped and
1475 place it in the displaced_step_request_queue. Whenever a displaced
1476 step finishes, we pick the next thread in the queue and start a new
1477 displaced step operation on it. See displaced_step_prepare and
1478 displaced_step_fixup for details. */
1480 /* Per-inferior displaced stepping state. */
1481 struct displaced_step_inferior_state
1483 /* Pointer to next in linked list. */
1484 struct displaced_step_inferior_state
*next
;
1486 /* The process this displaced step state refers to. */
1489 /* True if preparing a displaced step ever failed. If so, we won't
1490 try displaced stepping for this inferior again. */
1493 /* If this is not null_ptid, this is the thread carrying out a
1494 displaced single-step in process PID. This thread's state will
1495 require fixing up once it has completed its step. */
1498 /* The architecture the thread had when we stepped it. */
1499 struct gdbarch
*step_gdbarch
;
1501 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1502 for post-step cleanup. */
1503 struct displaced_step_closure
*step_closure
;
1505 /* The address of the original instruction, and the copy we
1507 CORE_ADDR step_original
, step_copy
;
1509 /* Saved contents of copy area. */
1510 gdb_byte
*step_saved_copy
;
1513 /* The list of states of processes involved in displaced stepping
1515 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1517 /* Get the displaced stepping state of process PID. */
1519 static struct displaced_step_inferior_state
*
1520 get_displaced_stepping_state (int pid
)
1522 struct displaced_step_inferior_state
*state
;
1524 for (state
= displaced_step_inferior_states
;
1526 state
= state
->next
)
1527 if (state
->pid
== pid
)
1533 /* Returns true if any inferior has a thread doing a displaced
1537 displaced_step_in_progress_any_inferior (void)
1539 struct displaced_step_inferior_state
*state
;
1541 for (state
= displaced_step_inferior_states
;
1543 state
= state
->next
)
1544 if (!ptid_equal (state
->step_ptid
, null_ptid
))
1550 /* Return true if thread represented by PTID is doing a displaced
1554 displaced_step_in_progress_thread (ptid_t ptid
)
1556 struct displaced_step_inferior_state
*displaced
;
1558 gdb_assert (!ptid_equal (ptid
, null_ptid
));
1560 displaced
= get_displaced_stepping_state (ptid_get_pid (ptid
));
1562 return (displaced
!= NULL
&& ptid_equal (displaced
->step_ptid
, ptid
));
1565 /* Return true if process PID has a thread doing a displaced step. */
1568 displaced_step_in_progress (int pid
)
1570 struct displaced_step_inferior_state
*displaced
;
1572 displaced
= get_displaced_stepping_state (pid
);
1573 if (displaced
!= NULL
&& !ptid_equal (displaced
->step_ptid
, null_ptid
))
1579 /* Add a new displaced stepping state for process PID to the displaced
1580 stepping state list, or return a pointer to an already existing
1581 entry, if it already exists. Never returns NULL. */
1583 static struct displaced_step_inferior_state
*
1584 add_displaced_stepping_state (int pid
)
1586 struct displaced_step_inferior_state
*state
;
1588 for (state
= displaced_step_inferior_states
;
1590 state
= state
->next
)
1591 if (state
->pid
== pid
)
1594 state
= XCNEW (struct displaced_step_inferior_state
);
1596 state
->next
= displaced_step_inferior_states
;
1597 displaced_step_inferior_states
= state
;
1602 /* If inferior is in displaced stepping, and ADDR equals to starting address
1603 of copy area, return corresponding displaced_step_closure. Otherwise,
1606 struct displaced_step_closure
*
1607 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1609 struct displaced_step_inferior_state
*displaced
1610 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1612 /* If checking the mode of displaced instruction in copy area. */
1613 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1614 && (displaced
->step_copy
== addr
))
1615 return displaced
->step_closure
;
1620 /* Remove the displaced stepping state of process PID. */
1623 remove_displaced_stepping_state (int pid
)
1625 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1627 gdb_assert (pid
!= 0);
1629 it
= displaced_step_inferior_states
;
1630 prev_next_p
= &displaced_step_inferior_states
;
1635 *prev_next_p
= it
->next
;
1640 prev_next_p
= &it
->next
;
1646 infrun_inferior_exit (struct inferior
*inf
)
1648 remove_displaced_stepping_state (inf
->pid
);
1651 /* If ON, and the architecture supports it, GDB will use displaced
1652 stepping to step over breakpoints. If OFF, or if the architecture
1653 doesn't support it, GDB will instead use the traditional
1654 hold-and-step approach. If AUTO (which is the default), GDB will
1655 decide which technique to use to step over breakpoints depending on
1656 which of all-stop or non-stop mode is active --- displaced stepping
1657 in non-stop mode; hold-and-step in all-stop mode. */
1659 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1662 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1663 struct cmd_list_element
*c
,
1666 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1667 fprintf_filtered (file
,
1668 _("Debugger's willingness to use displaced stepping "
1669 "to step over breakpoints is %s (currently %s).\n"),
1670 value
, target_is_non_stop_p () ? "on" : "off");
1672 fprintf_filtered (file
,
1673 _("Debugger's willingness to use displaced stepping "
1674 "to step over breakpoints is %s.\n"), value
);
1677 /* Return non-zero if displaced stepping can/should be used to step
1678 over breakpoints of thread TP. */
1681 use_displaced_stepping (struct thread_info
*tp
)
1683 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
1684 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1685 struct displaced_step_inferior_state
*displaced_state
;
1687 displaced_state
= get_displaced_stepping_state (ptid_get_pid (tp
->ptid
));
1689 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1690 && target_is_non_stop_p ())
1691 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1692 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1693 && find_record_target () == NULL
1694 && (displaced_state
== NULL
1695 || !displaced_state
->failed_before
));
1698 /* Clean out any stray displaced stepping state. */
1700 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1702 /* Indicate that there is no cleanup pending. */
1703 displaced
->step_ptid
= null_ptid
;
1705 if (displaced
->step_closure
)
1707 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1708 displaced
->step_closure
);
1709 displaced
->step_closure
= NULL
;
1714 displaced_step_clear_cleanup (void *arg
)
1716 struct displaced_step_inferior_state
*state
1717 = (struct displaced_step_inferior_state
*) arg
;
1719 displaced_step_clear (state
);
1722 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1724 displaced_step_dump_bytes (struct ui_file
*file
,
1725 const gdb_byte
*buf
,
1730 for (i
= 0; i
< len
; i
++)
1731 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1732 fputs_unfiltered ("\n", file
);
1735 /* Prepare to single-step, using displaced stepping.
1737 Note that we cannot use displaced stepping when we have a signal to
1738 deliver. If we have a signal to deliver and an instruction to step
1739 over, then after the step, there will be no indication from the
1740 target whether the thread entered a signal handler or ignored the
1741 signal and stepped over the instruction successfully --- both cases
1742 result in a simple SIGTRAP. In the first case we mustn't do a
1743 fixup, and in the second case we must --- but we can't tell which.
1744 Comments in the code for 'random signals' in handle_inferior_event
1745 explain how we handle this case instead.
1747 Returns 1 if preparing was successful -- this thread is going to be
1748 stepped now; 0 if displaced stepping this thread got queued; or -1
1749 if this instruction can't be displaced stepped. */
1752 displaced_step_prepare_throw (ptid_t ptid
)
1754 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1755 struct thread_info
*tp
= find_thread_ptid (ptid
);
1756 struct regcache
*regcache
= get_thread_regcache (ptid
);
1757 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1758 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1759 CORE_ADDR original
, copy
;
1761 struct displaced_step_closure
*closure
;
1762 struct displaced_step_inferior_state
*displaced
;
1765 /* We should never reach this function if the architecture does not
1766 support displaced stepping. */
1767 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1769 /* Nor if the thread isn't meant to step over a breakpoint. */
1770 gdb_assert (tp
->control
.trap_expected
);
1772 /* Disable range stepping while executing in the scratch pad. We
1773 want a single-step even if executing the displaced instruction in
1774 the scratch buffer lands within the stepping range (e.g., a
1776 tp
->control
.may_range_step
= 0;
1778 /* We have to displaced step one thread at a time, as we only have
1779 access to a single scratch space per inferior. */
1781 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1783 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1785 /* Already waiting for a displaced step to finish. Defer this
1786 request and place in queue. */
1788 if (debug_displaced
)
1789 fprintf_unfiltered (gdb_stdlog
,
1790 "displaced: deferring step of %s\n",
1791 target_pid_to_str (ptid
));
1793 thread_step_over_chain_enqueue (tp
);
1798 if (debug_displaced
)
1799 fprintf_unfiltered (gdb_stdlog
,
1800 "displaced: stepping %s now\n",
1801 target_pid_to_str (ptid
));
1804 displaced_step_clear (displaced
);
1806 old_cleanups
= save_inferior_ptid ();
1807 inferior_ptid
= ptid
;
1809 original
= regcache_read_pc (regcache
);
1811 copy
= gdbarch_displaced_step_location (gdbarch
);
1812 len
= gdbarch_max_insn_length (gdbarch
);
1814 if (breakpoint_in_range_p (aspace
, copy
, len
))
1816 /* There's a breakpoint set in the scratch pad location range
1817 (which is usually around the entry point). We'd either
1818 install it before resuming, which would overwrite/corrupt the
1819 scratch pad, or if it was already inserted, this displaced
1820 step would overwrite it. The latter is OK in the sense that
1821 we already assume that no thread is going to execute the code
1822 in the scratch pad range (after initial startup) anyway, but
1823 the former is unacceptable. Simply punt and fallback to
1824 stepping over this breakpoint in-line. */
1825 if (debug_displaced
)
1827 fprintf_unfiltered (gdb_stdlog
,
1828 "displaced: breakpoint set in scratch pad. "
1829 "Stepping over breakpoint in-line instead.\n");
1832 do_cleanups (old_cleanups
);
1836 /* Save the original contents of the copy area. */
1837 displaced
->step_saved_copy
= (gdb_byte
*) xmalloc (len
);
1838 ignore_cleanups
= make_cleanup (free_current_contents
,
1839 &displaced
->step_saved_copy
);
1840 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1842 throw_error (MEMORY_ERROR
,
1843 _("Error accessing memory address %s (%s) for "
1844 "displaced-stepping scratch space."),
1845 paddress (gdbarch
, copy
), safe_strerror (status
));
1846 if (debug_displaced
)
1848 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1849 paddress (gdbarch
, copy
));
1850 displaced_step_dump_bytes (gdb_stdlog
,
1851 displaced
->step_saved_copy
,
1855 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1856 original
, copy
, regcache
);
1857 if (closure
== NULL
)
1859 /* The architecture doesn't know how or want to displaced step
1860 this instruction or instruction sequence. Fallback to
1861 stepping over the breakpoint in-line. */
1862 do_cleanups (old_cleanups
);
1866 /* Save the information we need to fix things up if the step
1868 displaced
->step_ptid
= ptid
;
1869 displaced
->step_gdbarch
= gdbarch
;
1870 displaced
->step_closure
= closure
;
1871 displaced
->step_original
= original
;
1872 displaced
->step_copy
= copy
;
1874 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1876 /* Resume execution at the copy. */
1877 regcache_write_pc (regcache
, copy
);
1879 discard_cleanups (ignore_cleanups
);
1881 do_cleanups (old_cleanups
);
1883 if (debug_displaced
)
1884 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1885 paddress (gdbarch
, copy
));
1890 /* Wrapper for displaced_step_prepare_throw that disabled further
1891 attempts at displaced stepping if we get a memory error. */
1894 displaced_step_prepare (ptid_t ptid
)
1900 prepared
= displaced_step_prepare_throw (ptid
);
1902 CATCH (ex
, RETURN_MASK_ERROR
)
1904 struct displaced_step_inferior_state
*displaced_state
;
1906 if (ex
.error
!= MEMORY_ERROR
1907 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1908 throw_exception (ex
);
1912 fprintf_unfiltered (gdb_stdlog
,
1913 "infrun: disabling displaced stepping: %s\n",
1917 /* Be verbose if "set displaced-stepping" is "on", silent if
1919 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1921 warning (_("disabling displaced stepping: %s"),
1925 /* Disable further displaced stepping attempts. */
1927 = get_displaced_stepping_state (ptid_get_pid (ptid
));
1928 displaced_state
->failed_before
= 1;
1936 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1937 const gdb_byte
*myaddr
, int len
)
1939 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1941 inferior_ptid
= ptid
;
1942 write_memory (memaddr
, myaddr
, len
);
1943 do_cleanups (ptid_cleanup
);
1946 /* Restore the contents of the copy area for thread PTID. */
1949 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1952 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1954 write_memory_ptid (ptid
, displaced
->step_copy
,
1955 displaced
->step_saved_copy
, len
);
1956 if (debug_displaced
)
1957 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1958 target_pid_to_str (ptid
),
1959 paddress (displaced
->step_gdbarch
,
1960 displaced
->step_copy
));
1963 /* If we displaced stepped an instruction successfully, adjust
1964 registers and memory to yield the same effect the instruction would
1965 have had if we had executed it at its original address, and return
1966 1. If the instruction didn't complete, relocate the PC and return
1967 -1. If the thread wasn't displaced stepping, return 0. */
1970 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1972 struct cleanup
*old_cleanups
;
1973 struct displaced_step_inferior_state
*displaced
1974 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1977 /* Was any thread of this process doing a displaced step? */
1978 if (displaced
== NULL
)
1981 /* Was this event for the pid we displaced? */
1982 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1983 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1986 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1988 displaced_step_restore (displaced
, displaced
->step_ptid
);
1990 /* Fixup may need to read memory/registers. Switch to the thread
1991 that we're fixing up. Also, target_stopped_by_watchpoint checks
1992 the current thread. */
1993 switch_to_thread (event_ptid
);
1995 /* Did the instruction complete successfully? */
1996 if (signal
== GDB_SIGNAL_TRAP
1997 && !(target_stopped_by_watchpoint ()
1998 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
1999 || target_have_steppable_watchpoint
)))
2001 /* Fix up the resulting state. */
2002 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
2003 displaced
->step_closure
,
2004 displaced
->step_original
,
2005 displaced
->step_copy
,
2006 get_thread_regcache (displaced
->step_ptid
));
2011 /* Since the instruction didn't complete, all we can do is
2013 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
2014 CORE_ADDR pc
= regcache_read_pc (regcache
);
2016 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
2017 regcache_write_pc (regcache
, pc
);
2021 do_cleanups (old_cleanups
);
2023 displaced
->step_ptid
= null_ptid
;
2028 /* Data to be passed around while handling an event. This data is
2029 discarded between events. */
2030 struct execution_control_state
2033 /* The thread that got the event, if this was a thread event; NULL
2035 struct thread_info
*event_thread
;
2037 struct target_waitstatus ws
;
2038 int stop_func_filled_in
;
2039 CORE_ADDR stop_func_start
;
2040 CORE_ADDR stop_func_end
;
2041 const char *stop_func_name
;
2044 /* True if the event thread hit the single-step breakpoint of
2045 another thread. Thus the event doesn't cause a stop, the thread
2046 needs to be single-stepped past the single-step breakpoint before
2047 we can switch back to the original stepping thread. */
2048 int hit_singlestep_breakpoint
;
2051 /* Clear ECS and set it to point at TP. */
2054 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
2056 memset (ecs
, 0, sizeof (*ecs
));
2057 ecs
->event_thread
= tp
;
2058 ecs
->ptid
= tp
->ptid
;
2061 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
2062 static void prepare_to_wait (struct execution_control_state
*ecs
);
2063 static int keep_going_stepped_thread (struct thread_info
*tp
);
2064 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
2066 /* Are there any pending step-over requests? If so, run all we can
2067 now and return true. Otherwise, return false. */
2070 start_step_over (void)
2072 struct thread_info
*tp
, *next
;
2074 /* Don't start a new step-over if we already have an in-line
2075 step-over operation ongoing. */
2076 if (step_over_info_valid_p ())
2079 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
2081 struct execution_control_state ecss
;
2082 struct execution_control_state
*ecs
= &ecss
;
2083 step_over_what step_what
;
2084 int must_be_in_line
;
2086 next
= thread_step_over_chain_next (tp
);
2088 /* If this inferior already has a displaced step in process,
2089 don't start a new one. */
2090 if (displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2093 step_what
= thread_still_needs_step_over (tp
);
2094 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
2095 || ((step_what
& STEP_OVER_BREAKPOINT
)
2096 && !use_displaced_stepping (tp
)));
2098 /* We currently stop all threads of all processes to step-over
2099 in-line. If we need to start a new in-line step-over, let
2100 any pending displaced steps finish first. */
2101 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
2104 thread_step_over_chain_remove (tp
);
2106 if (step_over_queue_head
== NULL
)
2109 fprintf_unfiltered (gdb_stdlog
,
2110 "infrun: step-over queue now empty\n");
2113 if (tp
->control
.trap_expected
2117 internal_error (__FILE__
, __LINE__
,
2118 "[%s] has inconsistent state: "
2119 "trap_expected=%d, resumed=%d, executing=%d\n",
2120 target_pid_to_str (tp
->ptid
),
2121 tp
->control
.trap_expected
,
2127 fprintf_unfiltered (gdb_stdlog
,
2128 "infrun: resuming [%s] for step-over\n",
2129 target_pid_to_str (tp
->ptid
));
2131 /* keep_going_pass_signal skips the step-over if the breakpoint
2132 is no longer inserted. In all-stop, we want to keep looking
2133 for a thread that needs a step-over instead of resuming TP,
2134 because we wouldn't be able to resume anything else until the
2135 target stops again. In non-stop, the resume always resumes
2136 only TP, so it's OK to let the thread resume freely. */
2137 if (!target_is_non_stop_p () && !step_what
)
2140 switch_to_thread (tp
->ptid
);
2141 reset_ecs (ecs
, tp
);
2142 keep_going_pass_signal (ecs
);
2144 if (!ecs
->wait_some_more
)
2145 error (_("Command aborted."));
2147 gdb_assert (tp
->resumed
);
2149 /* If we started a new in-line step-over, we're done. */
2150 if (step_over_info_valid_p ())
2152 gdb_assert (tp
->control
.trap_expected
);
2156 if (!target_is_non_stop_p ())
2158 /* On all-stop, shouldn't have resumed unless we needed a
2160 gdb_assert (tp
->control
.trap_expected
2161 || tp
->step_after_step_resume_breakpoint
);
2163 /* With remote targets (at least), in all-stop, we can't
2164 issue any further remote commands until the program stops
2169 /* Either the thread no longer needed a step-over, or a new
2170 displaced stepping sequence started. Even in the latter
2171 case, continue looking. Maybe we can also start another
2172 displaced step on a thread of other process. */
2178 /* Update global variables holding ptids to hold NEW_PTID if they were
2179 holding OLD_PTID. */
2181 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2183 struct displaced_step_inferior_state
*displaced
;
2185 if (ptid_equal (inferior_ptid
, old_ptid
))
2186 inferior_ptid
= new_ptid
;
2188 for (displaced
= displaced_step_inferior_states
;
2190 displaced
= displaced
->next
)
2192 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
2193 displaced
->step_ptid
= new_ptid
;
2200 /* Things to clean up if we QUIT out of resume (). */
2202 resume_cleanups (void *ignore
)
2204 if (!ptid_equal (inferior_ptid
, null_ptid
))
2205 delete_single_step_breakpoints (inferior_thread ());
2210 static const char schedlock_off
[] = "off";
2211 static const char schedlock_on
[] = "on";
2212 static const char schedlock_step
[] = "step";
2213 static const char schedlock_replay
[] = "replay";
2214 static const char *const scheduler_enums
[] = {
2221 static const char *scheduler_mode
= schedlock_replay
;
2223 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2224 struct cmd_list_element
*c
, const char *value
)
2226 fprintf_filtered (file
,
2227 _("Mode for locking scheduler "
2228 "during execution is \"%s\".\n"),
2233 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
2235 if (!target_can_lock_scheduler
)
2237 scheduler_mode
= schedlock_off
;
2238 error (_("Target '%s' cannot support this command."), target_shortname
);
2242 /* True if execution commands resume all threads of all processes by
2243 default; otherwise, resume only threads of the current inferior
2245 int sched_multi
= 0;
2247 /* Try to setup for software single stepping over the specified location.
2248 Return 1 if target_resume() should use hardware single step.
2250 GDBARCH the current gdbarch.
2251 PC the location to step over. */
2254 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2258 if (execution_direction
== EXEC_FORWARD
2259 && gdbarch_software_single_step_p (gdbarch
)
2260 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
2270 user_visible_resume_ptid (int step
)
2276 /* With non-stop mode on, threads are always handled
2278 resume_ptid
= inferior_ptid
;
2280 else if ((scheduler_mode
== schedlock_on
)
2281 || (scheduler_mode
== schedlock_step
&& step
))
2283 /* User-settable 'scheduler' mode requires solo thread
2285 resume_ptid
= inferior_ptid
;
2287 else if ((scheduler_mode
== schedlock_replay
)
2288 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2290 /* User-settable 'scheduler' mode requires solo thread resume in replay
2292 resume_ptid
= inferior_ptid
;
2294 else if (!sched_multi
&& target_supports_multi_process ())
2296 /* Resume all threads of the current process (and none of other
2298 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2302 /* Resume all threads of all processes. */
2303 resume_ptid
= RESUME_ALL
;
2309 /* Return a ptid representing the set of threads that we will resume,
2310 in the perspective of the target, assuming run control handling
2311 does not require leaving some threads stopped (e.g., stepping past
2312 breakpoint). USER_STEP indicates whether we're about to start the
2313 target for a stepping command. */
2316 internal_resume_ptid (int user_step
)
2318 /* In non-stop, we always control threads individually. Note that
2319 the target may always work in non-stop mode even with "set
2320 non-stop off", in which case user_visible_resume_ptid could
2321 return a wildcard ptid. */
2322 if (target_is_non_stop_p ())
2323 return inferior_ptid
;
2325 return user_visible_resume_ptid (user_step
);
2328 /* Wrapper for target_resume, that handles infrun-specific
2332 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2334 struct thread_info
*tp
= inferior_thread ();
2336 /* Install inferior's terminal modes. */
2337 target_terminal_inferior ();
2339 /* Avoid confusing the next resume, if the next stop/resume
2340 happens to apply to another thread. */
2341 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2343 /* Advise target which signals may be handled silently.
2345 If we have removed breakpoints because we are stepping over one
2346 in-line (in any thread), we need to receive all signals to avoid
2347 accidentally skipping a breakpoint during execution of a signal
2350 Likewise if we're displaced stepping, otherwise a trap for a
2351 breakpoint in a signal handler might be confused with the
2352 displaced step finishing. We don't make the displaced_step_fixup
2353 step distinguish the cases instead, because:
2355 - a backtrace while stopped in the signal handler would show the
2356 scratch pad as frame older than the signal handler, instead of
2357 the real mainline code.
2359 - when the thread is later resumed, the signal handler would
2360 return to the scratch pad area, which would no longer be
2362 if (step_over_info_valid_p ()
2363 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2364 target_pass_signals (0, NULL
);
2366 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2368 target_resume (resume_ptid
, step
, sig
);
2371 /* Resume the inferior, but allow a QUIT. This is useful if the user
2372 wants to interrupt some lengthy single-stepping operation
2373 (for child processes, the SIGINT goes to the inferior, and so
2374 we get a SIGINT random_signal, but for remote debugging and perhaps
2375 other targets, that's not true).
2377 SIG is the signal to give the inferior (zero for none). */
2379 resume (enum gdb_signal sig
)
2381 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2382 struct regcache
*regcache
= get_current_regcache ();
2383 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2384 struct thread_info
*tp
= inferior_thread ();
2385 CORE_ADDR pc
= regcache_read_pc (regcache
);
2386 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2388 /* This represents the user's step vs continue request. When
2389 deciding whether "set scheduler-locking step" applies, it's the
2390 user's intention that counts. */
2391 const int user_step
= tp
->control
.stepping_command
;
2392 /* This represents what we'll actually request the target to do.
2393 This can decay from a step to a continue, if e.g., we need to
2394 implement single-stepping with breakpoints (software
2398 gdb_assert (!thread_is_in_step_over_chain (tp
));
2402 if (tp
->suspend
.waitstatus_pending_p
)
2408 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2409 fprintf_unfiltered (gdb_stdlog
,
2410 "infrun: resume: thread %s has pending wait status %s "
2411 "(currently_stepping=%d).\n",
2412 target_pid_to_str (tp
->ptid
), statstr
,
2413 currently_stepping (tp
));
2419 /* FIXME: What should we do if we are supposed to resume this
2420 thread with a signal? Maybe we should maintain a queue of
2421 pending signals to deliver. */
2422 if (sig
!= GDB_SIGNAL_0
)
2424 warning (_("Couldn't deliver signal %s to %s."),
2425 gdb_signal_to_name (sig
), target_pid_to_str (tp
->ptid
));
2428 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2429 discard_cleanups (old_cleanups
);
2431 if (target_can_async_p ())
2436 tp
->stepped_breakpoint
= 0;
2438 /* Depends on stepped_breakpoint. */
2439 step
= currently_stepping (tp
);
2441 if (current_inferior ()->waiting_for_vfork_done
)
2443 /* Don't try to single-step a vfork parent that is waiting for
2444 the child to get out of the shared memory region (by exec'ing
2445 or exiting). This is particularly important on software
2446 single-step archs, as the child process would trip on the
2447 software single step breakpoint inserted for the parent
2448 process. Since the parent will not actually execute any
2449 instruction until the child is out of the shared region (such
2450 are vfork's semantics), it is safe to simply continue it.
2451 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2452 the parent, and tell it to `keep_going', which automatically
2453 re-sets it stepping. */
2455 fprintf_unfiltered (gdb_stdlog
,
2456 "infrun: resume : clear step\n");
2461 fprintf_unfiltered (gdb_stdlog
,
2462 "infrun: resume (step=%d, signal=%s), "
2463 "trap_expected=%d, current thread [%s] at %s\n",
2464 step
, gdb_signal_to_symbol_string (sig
),
2465 tp
->control
.trap_expected
,
2466 target_pid_to_str (inferior_ptid
),
2467 paddress (gdbarch
, pc
));
2469 /* Normally, by the time we reach `resume', the breakpoints are either
2470 removed or inserted, as appropriate. The exception is if we're sitting
2471 at a permanent breakpoint; we need to step over it, but permanent
2472 breakpoints can't be removed. So we have to test for it here. */
2473 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2475 if (sig
!= GDB_SIGNAL_0
)
2477 /* We have a signal to pass to the inferior. The resume
2478 may, or may not take us to the signal handler. If this
2479 is a step, we'll need to stop in the signal handler, if
2480 there's one, (if the target supports stepping into
2481 handlers), or in the next mainline instruction, if
2482 there's no handler. If this is a continue, we need to be
2483 sure to run the handler with all breakpoints inserted.
2484 In all cases, set a breakpoint at the current address
2485 (where the handler returns to), and once that breakpoint
2486 is hit, resume skipping the permanent breakpoint. If
2487 that breakpoint isn't hit, then we've stepped into the
2488 signal handler (or hit some other event). We'll delete
2489 the step-resume breakpoint then. */
2492 fprintf_unfiltered (gdb_stdlog
,
2493 "infrun: resume: skipping permanent breakpoint, "
2494 "deliver signal first\n");
2496 clear_step_over_info ();
2497 tp
->control
.trap_expected
= 0;
2499 if (tp
->control
.step_resume_breakpoint
== NULL
)
2501 /* Set a "high-priority" step-resume, as we don't want
2502 user breakpoints at PC to trigger (again) when this
2504 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2505 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2507 tp
->step_after_step_resume_breakpoint
= step
;
2510 insert_breakpoints ();
2514 /* There's no signal to pass, we can go ahead and skip the
2515 permanent breakpoint manually. */
2517 fprintf_unfiltered (gdb_stdlog
,
2518 "infrun: resume: skipping permanent breakpoint\n");
2519 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2520 /* Update pc to reflect the new address from which we will
2521 execute instructions. */
2522 pc
= regcache_read_pc (regcache
);
2526 /* We've already advanced the PC, so the stepping part
2527 is done. Now we need to arrange for a trap to be
2528 reported to handle_inferior_event. Set a breakpoint
2529 at the current PC, and run to it. Don't update
2530 prev_pc, because if we end in
2531 switch_back_to_stepped_thread, we want the "expected
2532 thread advanced also" branch to be taken. IOW, we
2533 don't want this thread to step further from PC
2535 gdb_assert (!step_over_info_valid_p ());
2536 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2537 insert_breakpoints ();
2539 resume_ptid
= internal_resume_ptid (user_step
);
2540 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2541 discard_cleanups (old_cleanups
);
2548 /* If we have a breakpoint to step over, make sure to do a single
2549 step only. Same if we have software watchpoints. */
2550 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2551 tp
->control
.may_range_step
= 0;
2553 /* If enabled, step over breakpoints by executing a copy of the
2554 instruction at a different address.
2556 We can't use displaced stepping when we have a signal to deliver;
2557 the comments for displaced_step_prepare explain why. The
2558 comments in the handle_inferior event for dealing with 'random
2559 signals' explain what we do instead.
2561 We can't use displaced stepping when we are waiting for vfork_done
2562 event, displaced stepping breaks the vfork child similarly as single
2563 step software breakpoint. */
2564 if (tp
->control
.trap_expected
2565 && use_displaced_stepping (tp
)
2566 && !step_over_info_valid_p ()
2567 && sig
== GDB_SIGNAL_0
2568 && !current_inferior ()->waiting_for_vfork_done
)
2570 int prepared
= displaced_step_prepare (inferior_ptid
);
2575 fprintf_unfiltered (gdb_stdlog
,
2576 "Got placed in step-over queue\n");
2578 tp
->control
.trap_expected
= 0;
2579 discard_cleanups (old_cleanups
);
2582 else if (prepared
< 0)
2584 /* Fallback to stepping over the breakpoint in-line. */
2586 if (target_is_non_stop_p ())
2587 stop_all_threads ();
2589 set_step_over_info (get_regcache_aspace (regcache
),
2590 regcache_read_pc (regcache
), 0, tp
->global_num
);
2592 step
= maybe_software_singlestep (gdbarch
, pc
);
2594 insert_breakpoints ();
2596 else if (prepared
> 0)
2598 struct displaced_step_inferior_state
*displaced
;
2600 /* Update pc to reflect the new address from which we will
2601 execute instructions due to displaced stepping. */
2602 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2604 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2605 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2606 displaced
->step_closure
);
2610 /* Do we need to do it the hard way, w/temp breakpoints? */
2612 step
= maybe_software_singlestep (gdbarch
, pc
);
2614 /* Currently, our software single-step implementation leads to different
2615 results than hardware single-stepping in one situation: when stepping
2616 into delivering a signal which has an associated signal handler,
2617 hardware single-step will stop at the first instruction of the handler,
2618 while software single-step will simply skip execution of the handler.
2620 For now, this difference in behavior is accepted since there is no
2621 easy way to actually implement single-stepping into a signal handler
2622 without kernel support.
2624 However, there is one scenario where this difference leads to follow-on
2625 problems: if we're stepping off a breakpoint by removing all breakpoints
2626 and then single-stepping. In this case, the software single-step
2627 behavior means that even if there is a *breakpoint* in the signal
2628 handler, GDB still would not stop.
2630 Fortunately, we can at least fix this particular issue. We detect
2631 here the case where we are about to deliver a signal while software
2632 single-stepping with breakpoints removed. In this situation, we
2633 revert the decisions to remove all breakpoints and insert single-
2634 step breakpoints, and instead we install a step-resume breakpoint
2635 at the current address, deliver the signal without stepping, and
2636 once we arrive back at the step-resume breakpoint, actually step
2637 over the breakpoint we originally wanted to step over. */
2638 if (thread_has_single_step_breakpoints_set (tp
)
2639 && sig
!= GDB_SIGNAL_0
2640 && step_over_info_valid_p ())
2642 /* If we have nested signals or a pending signal is delivered
2643 immediately after a handler returns, might might already have
2644 a step-resume breakpoint set on the earlier handler. We cannot
2645 set another step-resume breakpoint; just continue on until the
2646 original breakpoint is hit. */
2647 if (tp
->control
.step_resume_breakpoint
== NULL
)
2649 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2650 tp
->step_after_step_resume_breakpoint
= 1;
2653 delete_single_step_breakpoints (tp
);
2655 clear_step_over_info ();
2656 tp
->control
.trap_expected
= 0;
2658 insert_breakpoints ();
2661 /* If STEP is set, it's a request to use hardware stepping
2662 facilities. But in that case, we should never
2663 use singlestep breakpoint. */
2664 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2666 /* Decide the set of threads to ask the target to resume. */
2667 if (tp
->control
.trap_expected
)
2669 /* We're allowing a thread to run past a breakpoint it has
2670 hit, either by single-stepping the thread with the breakpoint
2671 removed, or by displaced stepping, with the breakpoint inserted.
2672 In the former case, we need to single-step only this thread,
2673 and keep others stopped, as they can miss this breakpoint if
2674 allowed to run. That's not really a problem for displaced
2675 stepping, but, we still keep other threads stopped, in case
2676 another thread is also stopped for a breakpoint waiting for
2677 its turn in the displaced stepping queue. */
2678 resume_ptid
= inferior_ptid
;
2681 resume_ptid
= internal_resume_ptid (user_step
);
2683 if (execution_direction
!= EXEC_REVERSE
2684 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2686 /* There are two cases where we currently need to step a
2687 breakpoint instruction when we have a signal to deliver:
2689 - See handle_signal_stop where we handle random signals that
2690 could take out us out of the stepping range. Normally, in
2691 that case we end up continuing (instead of stepping) over the
2692 signal handler with a breakpoint at PC, but there are cases
2693 where we should _always_ single-step, even if we have a
2694 step-resume breakpoint, like when a software watchpoint is
2695 set. Assuming single-stepping and delivering a signal at the
2696 same time would takes us to the signal handler, then we could
2697 have removed the breakpoint at PC to step over it. However,
2698 some hardware step targets (like e.g., Mac OS) can't step
2699 into signal handlers, and for those, we need to leave the
2700 breakpoint at PC inserted, as otherwise if the handler
2701 recurses and executes PC again, it'll miss the breakpoint.
2702 So we leave the breakpoint inserted anyway, but we need to
2703 record that we tried to step a breakpoint instruction, so
2704 that adjust_pc_after_break doesn't end up confused.
2706 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2707 in one thread after another thread that was stepping had been
2708 momentarily paused for a step-over. When we re-resume the
2709 stepping thread, it may be resumed from that address with a
2710 breakpoint that hasn't trapped yet. Seen with
2711 gdb.threads/non-stop-fair-events.exp, on targets that don't
2712 do displaced stepping. */
2715 fprintf_unfiltered (gdb_stdlog
,
2716 "infrun: resume: [%s] stepped breakpoint\n",
2717 target_pid_to_str (tp
->ptid
));
2719 tp
->stepped_breakpoint
= 1;
2721 /* Most targets can step a breakpoint instruction, thus
2722 executing it normally. But if this one cannot, just
2723 continue and we will hit it anyway. */
2724 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2729 && tp
->control
.trap_expected
2730 && use_displaced_stepping (tp
)
2731 && !step_over_info_valid_p ())
2733 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2734 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2735 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2738 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2739 paddress (resume_gdbarch
, actual_pc
));
2740 read_memory (actual_pc
, buf
, sizeof (buf
));
2741 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2744 if (tp
->control
.may_range_step
)
2746 /* If we're resuming a thread with the PC out of the step
2747 range, then we're doing some nested/finer run control
2748 operation, like stepping the thread out of the dynamic
2749 linker or the displaced stepping scratch pad. We
2750 shouldn't have allowed a range step then. */
2751 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2754 do_target_resume (resume_ptid
, step
, sig
);
2756 discard_cleanups (old_cleanups
);
2763 /* Counter that tracks number of user visible stops. This can be used
2764 to tell whether a command has proceeded the inferior past the
2765 current location. This allows e.g., inferior function calls in
2766 breakpoint commands to not interrupt the command list. When the
2767 call finishes successfully, the inferior is standing at the same
2768 breakpoint as if nothing happened (and so we don't call
2770 static ULONGEST current_stop_id
;
2777 return current_stop_id
;
2780 /* Called when we report a user visible stop. */
2788 /* Clear out all variables saying what to do when inferior is continued.
2789 First do this, then set the ones you want, then call `proceed'. */
2792 clear_proceed_status_thread (struct thread_info
*tp
)
2795 fprintf_unfiltered (gdb_stdlog
,
2796 "infrun: clear_proceed_status_thread (%s)\n",
2797 target_pid_to_str (tp
->ptid
));
2799 /* If we're starting a new sequence, then the previous finished
2800 single-step is no longer relevant. */
2801 if (tp
->suspend
.waitstatus_pending_p
)
2803 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2806 fprintf_unfiltered (gdb_stdlog
,
2807 "infrun: clear_proceed_status: pending "
2808 "event of %s was a finished step. "
2810 target_pid_to_str (tp
->ptid
));
2812 tp
->suspend
.waitstatus_pending_p
= 0;
2813 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2815 else if (debug_infrun
)
2819 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2820 fprintf_unfiltered (gdb_stdlog
,
2821 "infrun: clear_proceed_status_thread: thread %s "
2822 "has pending wait status %s "
2823 "(currently_stepping=%d).\n",
2824 target_pid_to_str (tp
->ptid
), statstr
,
2825 currently_stepping (tp
));
2830 /* If this signal should not be seen by program, give it zero.
2831 Used for debugging signals. */
2832 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2833 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2835 thread_fsm_delete (tp
->thread_fsm
);
2836 tp
->thread_fsm
= NULL
;
2838 tp
->control
.trap_expected
= 0;
2839 tp
->control
.step_range_start
= 0;
2840 tp
->control
.step_range_end
= 0;
2841 tp
->control
.may_range_step
= 0;
2842 tp
->control
.step_frame_id
= null_frame_id
;
2843 tp
->control
.step_stack_frame_id
= null_frame_id
;
2844 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2845 tp
->control
.step_start_function
= NULL
;
2846 tp
->stop_requested
= 0;
2848 tp
->control
.stop_step
= 0;
2850 tp
->control
.proceed_to_finish
= 0;
2852 tp
->control
.command_interp
= NULL
;
2853 tp
->control
.stepping_command
= 0;
2855 /* Discard any remaining commands or status from previous stop. */
2856 bpstat_clear (&tp
->control
.stop_bpstat
);
2860 clear_proceed_status (int step
)
2862 /* With scheduler-locking replay, stop replaying other threads if we're
2863 not replaying the user-visible resume ptid.
2865 This is a convenience feature to not require the user to explicitly
2866 stop replaying the other threads. We're assuming that the user's
2867 intent is to resume tracing the recorded process. */
2868 if (!non_stop
&& scheduler_mode
== schedlock_replay
2869 && target_record_is_replaying (minus_one_ptid
)
2870 && !target_record_will_replay (user_visible_resume_ptid (step
),
2871 execution_direction
))
2872 target_record_stop_replaying ();
2876 struct thread_info
*tp
;
2879 resume_ptid
= user_visible_resume_ptid (step
);
2881 /* In all-stop mode, delete the per-thread status of all threads
2882 we're about to resume, implicitly and explicitly. */
2883 ALL_NON_EXITED_THREADS (tp
)
2885 if (!ptid_match (tp
->ptid
, resume_ptid
))
2887 clear_proceed_status_thread (tp
);
2891 if (!ptid_equal (inferior_ptid
, null_ptid
))
2893 struct inferior
*inferior
;
2897 /* If in non-stop mode, only delete the per-thread status of
2898 the current thread. */
2899 clear_proceed_status_thread (inferior_thread ());
2902 inferior
= current_inferior ();
2903 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2906 observer_notify_about_to_proceed ();
2909 /* Returns true if TP is still stopped at a breakpoint that needs
2910 stepping-over in order to make progress. If the breakpoint is gone
2911 meanwhile, we can skip the whole step-over dance. */
2914 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2916 if (tp
->stepping_over_breakpoint
)
2918 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2920 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2921 regcache_read_pc (regcache
))
2922 == ordinary_breakpoint_here
)
2925 tp
->stepping_over_breakpoint
= 0;
2931 /* Check whether thread TP still needs to start a step-over in order
2932 to make progress when resumed. Returns an bitwise or of enum
2933 step_over_what bits, indicating what needs to be stepped over. */
2935 static step_over_what
2936 thread_still_needs_step_over (struct thread_info
*tp
)
2938 step_over_what what
= 0;
2940 if (thread_still_needs_step_over_bp (tp
))
2941 what
|= STEP_OVER_BREAKPOINT
;
2943 if (tp
->stepping_over_watchpoint
2944 && !target_have_steppable_watchpoint
)
2945 what
|= STEP_OVER_WATCHPOINT
;
2950 /* Returns true if scheduler locking applies. STEP indicates whether
2951 we're about to do a step/next-like command to a thread. */
2954 schedlock_applies (struct thread_info
*tp
)
2956 return (scheduler_mode
== schedlock_on
2957 || (scheduler_mode
== schedlock_step
2958 && tp
->control
.stepping_command
)
2959 || (scheduler_mode
== schedlock_replay
2960 && target_record_will_replay (minus_one_ptid
,
2961 execution_direction
)));
2964 /* Basic routine for continuing the program in various fashions.
2966 ADDR is the address to resume at, or -1 for resume where stopped.
2967 SIGGNAL is the signal to give it, or 0 for none,
2968 or -1 for act according to how it stopped.
2969 STEP is nonzero if should trap after one instruction.
2970 -1 means return after that and print nothing.
2971 You should probably set various step_... variables
2972 before calling here, if you are stepping.
2974 You should call clear_proceed_status before calling proceed. */
2977 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2979 struct regcache
*regcache
;
2980 struct gdbarch
*gdbarch
;
2981 struct thread_info
*tp
;
2983 struct address_space
*aspace
;
2985 struct execution_control_state ecss
;
2986 struct execution_control_state
*ecs
= &ecss
;
2987 struct cleanup
*old_chain
;
2990 /* If we're stopped at a fork/vfork, follow the branch set by the
2991 "set follow-fork-mode" command; otherwise, we'll just proceed
2992 resuming the current thread. */
2993 if (!follow_fork ())
2995 /* The target for some reason decided not to resume. */
2997 if (target_can_async_p ())
2998 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3002 /* We'll update this if & when we switch to a new thread. */
3003 previous_inferior_ptid
= inferior_ptid
;
3005 regcache
= get_current_regcache ();
3006 gdbarch
= get_regcache_arch (regcache
);
3007 aspace
= get_regcache_aspace (regcache
);
3008 pc
= regcache_read_pc (regcache
);
3009 tp
= inferior_thread ();
3011 /* Fill in with reasonable starting values. */
3012 init_thread_stepping_state (tp
);
3014 gdb_assert (!thread_is_in_step_over_chain (tp
));
3016 if (addr
== (CORE_ADDR
) -1)
3019 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3020 && execution_direction
!= EXEC_REVERSE
)
3021 /* There is a breakpoint at the address we will resume at,
3022 step one instruction before inserting breakpoints so that
3023 we do not stop right away (and report a second hit at this
3026 Note, we don't do this in reverse, because we won't
3027 actually be executing the breakpoint insn anyway.
3028 We'll be (un-)executing the previous instruction. */
3029 tp
->stepping_over_breakpoint
= 1;
3030 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3031 && gdbarch_single_step_through_delay (gdbarch
,
3032 get_current_frame ()))
3033 /* We stepped onto an instruction that needs to be stepped
3034 again before re-inserting the breakpoint, do so. */
3035 tp
->stepping_over_breakpoint
= 1;
3039 regcache_write_pc (regcache
, addr
);
3042 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3043 tp
->suspend
.stop_signal
= siggnal
;
3045 /* Record the interpreter that issued the execution command that
3046 caused this thread to resume. If the top level interpreter is
3047 MI/async, and the execution command was a CLI command
3048 (next/step/etc.), we'll want to print stop event output to the MI
3049 console channel (the stepped-to line, etc.), as if the user
3050 entered the execution command on a real GDB console. */
3051 tp
->control
.command_interp
= command_interp ();
3053 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
3055 /* If an exception is thrown from this point on, make sure to
3056 propagate GDB's knowledge of the executing state to the
3057 frontend/user running state. */
3058 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
3060 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3061 threads (e.g., we might need to set threads stepping over
3062 breakpoints first), from the user/frontend's point of view, all
3063 threads in RESUME_PTID are now running. Unless we're calling an
3064 inferior function, as in that case we pretend the inferior
3065 doesn't run at all. */
3066 if (!tp
->control
.in_infcall
)
3067 set_running (resume_ptid
, 1);
3070 fprintf_unfiltered (gdb_stdlog
,
3071 "infrun: proceed (addr=%s, signal=%s)\n",
3072 paddress (gdbarch
, addr
),
3073 gdb_signal_to_symbol_string (siggnal
));
3075 annotate_starting ();
3077 /* Make sure that output from GDB appears before output from the
3079 gdb_flush (gdb_stdout
);
3081 /* In a multi-threaded task we may select another thread and
3082 then continue or step.
3084 But if a thread that we're resuming had stopped at a breakpoint,
3085 it will immediately cause another breakpoint stop without any
3086 execution (i.e. it will report a breakpoint hit incorrectly). So
3087 we must step over it first.
3089 Look for threads other than the current (TP) that reported a
3090 breakpoint hit and haven't been resumed yet since. */
3092 /* If scheduler locking applies, we can avoid iterating over all
3094 if (!non_stop
&& !schedlock_applies (tp
))
3096 struct thread_info
*current
= tp
;
3098 ALL_NON_EXITED_THREADS (tp
)
3100 /* Ignore the current thread here. It's handled
3105 /* Ignore threads of processes we're not resuming. */
3106 if (!ptid_match (tp
->ptid
, resume_ptid
))
3109 if (!thread_still_needs_step_over (tp
))
3112 gdb_assert (!thread_is_in_step_over_chain (tp
));
3115 fprintf_unfiltered (gdb_stdlog
,
3116 "infrun: need to step-over [%s] first\n",
3117 target_pid_to_str (tp
->ptid
));
3119 thread_step_over_chain_enqueue (tp
);
3125 /* Enqueue the current thread last, so that we move all other
3126 threads over their breakpoints first. */
3127 if (tp
->stepping_over_breakpoint
)
3128 thread_step_over_chain_enqueue (tp
);
3130 /* If the thread isn't started, we'll still need to set its prev_pc,
3131 so that switch_back_to_stepped_thread knows the thread hasn't
3132 advanced. Must do this before resuming any thread, as in
3133 all-stop/remote, once we resume we can't send any other packet
3134 until the target stops again. */
3135 tp
->prev_pc
= regcache_read_pc (regcache
);
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 discard_cleanups (old_chain
);
3203 /* Tell the event loop to wait for it to stop. If the target
3204 supports asynchronous execution, it'll do this from within
3206 if (!target_can_async_p ())
3207 mark_async_event_handler (infrun_async_inferior_event_token
);
3211 /* Start remote-debugging of a machine over a serial link. */
3214 start_remote (int from_tty
)
3216 struct inferior
*inferior
;
3218 inferior
= current_inferior ();
3219 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3221 /* Always go on waiting for the target, regardless of the mode. */
3222 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3223 indicate to wait_for_inferior that a target should timeout if
3224 nothing is returned (instead of just blocking). Because of this,
3225 targets expecting an immediate response need to, internally, set
3226 things up so that the target_wait() is forced to eventually
3228 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3229 differentiate to its caller what the state of the target is after
3230 the initial open has been performed. Here we're assuming that
3231 the target has stopped. It should be possible to eventually have
3232 target_open() return to the caller an indication that the target
3233 is currently running and GDB state should be set to the same as
3234 for an async run. */
3235 wait_for_inferior ();
3237 /* Now that the inferior has stopped, do any bookkeeping like
3238 loading shared libraries. We want to do this before normal_stop,
3239 so that the displayed frame is up to date. */
3240 post_create_inferior (¤t_target
, from_tty
);
3245 /* Initialize static vars when a new inferior begins. */
3248 init_wait_for_inferior (void)
3250 /* These are meaningless until the first time through wait_for_inferior. */
3252 breakpoint_init_inferior (inf_starting
);
3254 clear_proceed_status (0);
3256 target_last_wait_ptid
= minus_one_ptid
;
3258 previous_inferior_ptid
= inferior_ptid
;
3260 /* Discard any skipped inlined frames. */
3261 clear_inline_frame_state (minus_one_ptid
);
3266 static void handle_inferior_event (struct execution_control_state
*ecs
);
3268 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3269 struct execution_control_state
*ecs
);
3270 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3271 struct execution_control_state
*ecs
);
3272 static void handle_signal_stop (struct execution_control_state
*ecs
);
3273 static void check_exception_resume (struct execution_control_state
*,
3274 struct frame_info
*);
3276 static void end_stepping_range (struct execution_control_state
*ecs
);
3277 static void stop_waiting (struct execution_control_state
*ecs
);
3278 static void keep_going (struct execution_control_state
*ecs
);
3279 static void process_event_stop_test (struct execution_control_state
*ecs
);
3280 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3282 /* Callback for iterate over threads. If the thread is stopped, but
3283 the user/frontend doesn't know about that yet, go through
3284 normal_stop, as if the thread had just stopped now. ARG points at
3285 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
3286 ptid_is_pid(PTID) is true, applies to all threads of the process
3287 pointed at by PTID. Otherwise, apply only to the thread pointed by
3291 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
3293 ptid_t ptid
= * (ptid_t
*) arg
;
3295 if ((ptid_equal (info
->ptid
, ptid
)
3296 || ptid_equal (minus_one_ptid
, ptid
)
3297 || (ptid_is_pid (ptid
)
3298 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
3299 && is_running (info
->ptid
)
3300 && !is_executing (info
->ptid
))
3302 struct cleanup
*old_chain
;
3303 struct execution_control_state ecss
;
3304 struct execution_control_state
*ecs
= &ecss
;
3306 memset (ecs
, 0, sizeof (*ecs
));
3308 old_chain
= make_cleanup_restore_current_thread ();
3310 overlay_cache_invalid
= 1;
3311 /* Flush target cache before starting to handle each event.
3312 Target was running and cache could be stale. This is just a
3313 heuristic. Running threads may modify target memory, but we
3314 don't get any event. */
3315 target_dcache_invalidate ();
3317 /* Go through handle_inferior_event/normal_stop, so we always
3318 have consistent output as if the stop event had been
3320 ecs
->ptid
= info
->ptid
;
3321 ecs
->event_thread
= info
;
3322 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
3323 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
3325 handle_inferior_event (ecs
);
3327 if (!ecs
->wait_some_more
)
3329 /* Cancel any running execution command. */
3330 thread_cancel_execution_command (info
);
3335 do_cleanups (old_chain
);
3341 /* This function is attached as a "thread_stop_requested" observer.
3342 Cleanup local state that assumed the PTID was to be resumed, and
3343 report the stop to the frontend. */
3346 infrun_thread_stop_requested (ptid_t ptid
)
3348 struct thread_info
*tp
;
3350 /* PTID was requested to stop. Remove matching threads from the
3351 step-over queue, so we don't try to resume them
3353 ALL_NON_EXITED_THREADS (tp
)
3354 if (ptid_match (tp
->ptid
, ptid
))
3356 if (thread_is_in_step_over_chain (tp
))
3357 thread_step_over_chain_remove (tp
);
3360 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
3364 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3366 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3367 nullify_last_target_wait_ptid ();
3370 /* Delete the step resume, single-step and longjmp/exception resume
3371 breakpoints of TP. */
3374 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3376 delete_step_resume_breakpoint (tp
);
3377 delete_exception_resume_breakpoint (tp
);
3378 delete_single_step_breakpoints (tp
);
3381 /* If the target still has execution, call FUNC for each thread that
3382 just stopped. In all-stop, that's all the non-exited threads; in
3383 non-stop, that's the current thread, only. */
3385 typedef void (*for_each_just_stopped_thread_callback_func
)
3386 (struct thread_info
*tp
);
3389 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3391 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3394 if (target_is_non_stop_p ())
3396 /* If in non-stop mode, only the current thread stopped. */
3397 func (inferior_thread ());
3401 struct thread_info
*tp
;
3403 /* In all-stop mode, all threads have stopped. */
3404 ALL_NON_EXITED_THREADS (tp
)
3411 /* Delete the step resume and longjmp/exception resume breakpoints of
3412 the threads that just stopped. */
3415 delete_just_stopped_threads_infrun_breakpoints (void)
3417 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3420 /* Delete the single-step breakpoints of the threads that just
3424 delete_just_stopped_threads_single_step_breakpoints (void)
3426 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3429 /* A cleanup wrapper. */
3432 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3434 delete_just_stopped_threads_infrun_breakpoints ();
3440 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3441 const struct target_waitstatus
*ws
)
3443 char *status_string
= target_waitstatus_to_string (ws
);
3444 struct ui_file
*tmp_stream
= mem_fileopen ();
3447 /* The text is split over several lines because it was getting too long.
3448 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3449 output as a unit; we want only one timestamp printed if debug_timestamp
3452 fprintf_unfiltered (tmp_stream
,
3453 "infrun: target_wait (%d.%ld.%ld",
3454 ptid_get_pid (waiton_ptid
),
3455 ptid_get_lwp (waiton_ptid
),
3456 ptid_get_tid (waiton_ptid
));
3457 if (ptid_get_pid (waiton_ptid
) != -1)
3458 fprintf_unfiltered (tmp_stream
,
3459 " [%s]", target_pid_to_str (waiton_ptid
));
3460 fprintf_unfiltered (tmp_stream
, ", status) =\n");
3461 fprintf_unfiltered (tmp_stream
,
3462 "infrun: %d.%ld.%ld [%s],\n",
3463 ptid_get_pid (result_ptid
),
3464 ptid_get_lwp (result_ptid
),
3465 ptid_get_tid (result_ptid
),
3466 target_pid_to_str (result_ptid
));
3467 fprintf_unfiltered (tmp_stream
,
3471 text
= ui_file_xstrdup (tmp_stream
, NULL
);
3473 /* This uses %s in part to handle %'s in the text, but also to avoid
3474 a gcc error: the format attribute requires a string literal. */
3475 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
3477 xfree (status_string
);
3479 ui_file_delete (tmp_stream
);
3482 /* Select a thread at random, out of those which are resumed and have
3485 static struct thread_info
*
3486 random_pending_event_thread (ptid_t waiton_ptid
)
3488 struct thread_info
*event_tp
;
3490 int random_selector
;
3492 /* First see how many events we have. Count only resumed threads
3493 that have an event pending. */
3494 ALL_NON_EXITED_THREADS (event_tp
)
3495 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3496 && event_tp
->resumed
3497 && event_tp
->suspend
.waitstatus_pending_p
)
3500 if (num_events
== 0)
3503 /* Now randomly pick a thread out of those that have had events. */
3504 random_selector
= (int)
3505 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3507 if (debug_infrun
&& num_events
> 1)
3508 fprintf_unfiltered (gdb_stdlog
,
3509 "infrun: Found %d events, selecting #%d\n",
3510 num_events
, random_selector
);
3512 /* Select the Nth thread that has had an event. */
3513 ALL_NON_EXITED_THREADS (event_tp
)
3514 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3515 && event_tp
->resumed
3516 && event_tp
->suspend
.waitstatus_pending_p
)
3517 if (random_selector
-- == 0)
3523 /* Wrapper for target_wait that first checks whether threads have
3524 pending statuses to report before actually asking the target for
3528 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3531 struct thread_info
*tp
;
3533 /* First check if there is a resumed thread with a wait status
3535 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
3537 tp
= random_pending_event_thread (ptid
);
3542 fprintf_unfiltered (gdb_stdlog
,
3543 "infrun: Waiting for specific thread %s.\n",
3544 target_pid_to_str (ptid
));
3546 /* We have a specific thread to check. */
3547 tp
= find_thread_ptid (ptid
);
3548 gdb_assert (tp
!= NULL
);
3549 if (!tp
->suspend
.waitstatus_pending_p
)
3554 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3555 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3557 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
3558 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3562 pc
= regcache_read_pc (regcache
);
3564 if (pc
!= tp
->suspend
.stop_pc
)
3567 fprintf_unfiltered (gdb_stdlog
,
3568 "infrun: PC of %s changed. was=%s, now=%s\n",
3569 target_pid_to_str (tp
->ptid
),
3570 paddress (gdbarch
, tp
->prev_pc
),
3571 paddress (gdbarch
, pc
));
3574 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3577 fprintf_unfiltered (gdb_stdlog
,
3578 "infrun: previous breakpoint of %s, at %s gone\n",
3579 target_pid_to_str (tp
->ptid
),
3580 paddress (gdbarch
, pc
));
3588 fprintf_unfiltered (gdb_stdlog
,
3589 "infrun: pending event of %s cancelled.\n",
3590 target_pid_to_str (tp
->ptid
));
3592 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3593 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3603 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3604 fprintf_unfiltered (gdb_stdlog
,
3605 "infrun: Using pending wait status %s for %s.\n",
3607 target_pid_to_str (tp
->ptid
));
3611 /* Now that we've selected our final event LWP, un-adjust its PC
3612 if it was a software breakpoint (and the target doesn't
3613 always adjust the PC itself). */
3614 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3615 && !target_supports_stopped_by_sw_breakpoint ())
3617 struct regcache
*regcache
;
3618 struct gdbarch
*gdbarch
;
3621 regcache
= get_thread_regcache (tp
->ptid
);
3622 gdbarch
= get_regcache_arch (regcache
);
3624 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3629 pc
= regcache_read_pc (regcache
);
3630 regcache_write_pc (regcache
, pc
+ decr_pc
);
3634 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3635 *status
= tp
->suspend
.waitstatus
;
3636 tp
->suspend
.waitstatus_pending_p
= 0;
3638 /* Wake up the event loop again, until all pending events are
3640 if (target_is_async_p ())
3641 mark_async_event_handler (infrun_async_inferior_event_token
);
3645 /* But if we don't find one, we'll have to wait. */
3647 if (deprecated_target_wait_hook
)
3648 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3650 event_ptid
= target_wait (ptid
, status
, options
);
3655 /* Prepare and stabilize the inferior for detaching it. E.g.,
3656 detaching while a thread is displaced stepping is a recipe for
3657 crashing it, as nothing would readjust the PC out of the scratch
3661 prepare_for_detach (void)
3663 struct inferior
*inf
= current_inferior ();
3664 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3665 struct cleanup
*old_chain_1
;
3666 struct displaced_step_inferior_state
*displaced
;
3668 displaced
= get_displaced_stepping_state (inf
->pid
);
3670 /* Is any thread of this process displaced stepping? If not,
3671 there's nothing else to do. */
3672 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3676 fprintf_unfiltered (gdb_stdlog
,
3677 "displaced-stepping in-process while detaching");
3679 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3682 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3684 struct cleanup
*old_chain_2
;
3685 struct execution_control_state ecss
;
3686 struct execution_control_state
*ecs
;
3689 memset (ecs
, 0, sizeof (*ecs
));
3691 overlay_cache_invalid
= 1;
3692 /* Flush target cache before starting to handle each event.
3693 Target was running and cache could be stale. This is just a
3694 heuristic. Running threads may modify target memory, but we
3695 don't get any event. */
3696 target_dcache_invalidate ();
3698 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3701 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3703 /* If an error happens while handling the event, propagate GDB's
3704 knowledge of the executing state to the frontend/user running
3706 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3709 /* Now figure out what to do with the result of the result. */
3710 handle_inferior_event (ecs
);
3712 /* No error, don't finish the state yet. */
3713 discard_cleanups (old_chain_2
);
3715 /* Breakpoints and watchpoints are not installed on the target
3716 at this point, and signals are passed directly to the
3717 inferior, so this must mean the process is gone. */
3718 if (!ecs
->wait_some_more
)
3720 discard_cleanups (old_chain_1
);
3721 error (_("Program exited while detaching"));
3725 discard_cleanups (old_chain_1
);
3728 /* Wait for control to return from inferior to debugger.
3730 If inferior gets a signal, we may decide to start it up again
3731 instead of returning. That is why there is a loop in this function.
3732 When this function actually returns it means the inferior
3733 should be left stopped and GDB should read more commands. */
3736 wait_for_inferior (void)
3738 struct cleanup
*old_cleanups
;
3739 struct cleanup
*thread_state_chain
;
3743 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3746 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3749 /* If an error happens while handling the event, propagate GDB's
3750 knowledge of the executing state to the frontend/user running
3752 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3756 struct execution_control_state ecss
;
3757 struct execution_control_state
*ecs
= &ecss
;
3758 ptid_t waiton_ptid
= minus_one_ptid
;
3760 memset (ecs
, 0, sizeof (*ecs
));
3762 overlay_cache_invalid
= 1;
3764 /* Flush target cache before starting to handle each event.
3765 Target was running and cache could be stale. This is just a
3766 heuristic. Running threads may modify target memory, but we
3767 don't get any event. */
3768 target_dcache_invalidate ();
3770 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3773 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3775 /* Now figure out what to do with the result of the result. */
3776 handle_inferior_event (ecs
);
3778 if (!ecs
->wait_some_more
)
3782 /* No error, don't finish the state yet. */
3783 discard_cleanups (thread_state_chain
);
3785 do_cleanups (old_cleanups
);
3788 /* Cleanup that reinstalls the readline callback handler, if the
3789 target is running in the background. If while handling the target
3790 event something triggered a secondary prompt, like e.g., a
3791 pagination prompt, we'll have removed the callback handler (see
3792 gdb_readline_wrapper_line). Need to do this as we go back to the
3793 event loop, ready to process further input. Note this has no
3794 effect if the handler hasn't actually been removed, because calling
3795 rl_callback_handler_install resets the line buffer, thus losing
3799 reinstall_readline_callback_handler_cleanup (void *arg
)
3801 struct ui
*ui
= current_ui
;
3805 /* We're not going back to the top level event loop yet. Don't
3806 install the readline callback, as it'd prep the terminal,
3807 readline-style (raw, noecho) (e.g., --batch). We'll install
3808 it the next time the prompt is displayed, when we're ready
3813 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3814 gdb_rl_callback_handler_reinstall ();
3817 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3818 that's just the event thread. In all-stop, that's all threads. */
3821 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3823 struct thread_info
*thr
= ecs
->event_thread
;
3825 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3826 thread_fsm_clean_up (thr
->thread_fsm
);
3830 ALL_NON_EXITED_THREADS (thr
)
3832 if (thr
->thread_fsm
== NULL
)
3834 if (thr
== ecs
->event_thread
)
3837 switch_to_thread (thr
->ptid
);
3838 thread_fsm_clean_up (thr
->thread_fsm
);
3841 if (ecs
->event_thread
!= NULL
)
3842 switch_to_thread (ecs
->event_thread
->ptid
);
3846 /* Helper for all_uis_check_sync_execution_done that works on the
3850 check_curr_ui_sync_execution_done (void)
3852 struct ui
*ui
= current_ui
;
3854 if (ui
->prompt_state
== PROMPT_NEEDED
3856 && !gdb_in_secondary_prompt_p (ui
))
3858 target_terminal_ours ();
3859 observer_notify_sync_execution_done ();
3866 all_uis_check_sync_execution_done (void)
3868 struct switch_thru_all_uis state
;
3870 SWITCH_THRU_ALL_UIS (state
)
3872 check_curr_ui_sync_execution_done ();
3876 /* A cleanup that restores the execution direction to the value saved
3880 restore_execution_direction (void *arg
)
3882 enum exec_direction_kind
*save_exec_dir
= (enum exec_direction_kind
*) arg
;
3884 execution_direction
= *save_exec_dir
;
3887 /* Asynchronous version of wait_for_inferior. It is called by the
3888 event loop whenever a change of state is detected on the file
3889 descriptor corresponding to the target. It can be called more than
3890 once to complete a single execution command. In such cases we need
3891 to keep the state in a global variable ECSS. If it is the last time
3892 that this function is called for a single execution command, then
3893 report to the user that the inferior has stopped, and do the
3894 necessary cleanups. */
3897 fetch_inferior_event (void *client_data
)
3899 struct execution_control_state ecss
;
3900 struct execution_control_state
*ecs
= &ecss
;
3901 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3902 struct cleanup
*ts_old_chain
;
3903 enum exec_direction_kind save_exec_dir
= execution_direction
;
3905 ptid_t waiton_ptid
= minus_one_ptid
;
3907 memset (ecs
, 0, sizeof (*ecs
));
3909 /* Events are always processed with the main UI as current UI. This
3910 way, warnings, debug output, etc. are always consistently sent to
3911 the main console. */
3912 make_cleanup (restore_ui_cleanup
, current_ui
);
3913 current_ui
= main_ui
;
3915 /* End up with readline processing input, if necessary. */
3916 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3918 /* We're handling a live event, so make sure we're doing live
3919 debugging. If we're looking at traceframes while the target is
3920 running, we're going to need to get back to that mode after
3921 handling the event. */
3924 make_cleanup_restore_current_traceframe ();
3925 set_current_traceframe (-1);
3929 /* In non-stop mode, the user/frontend should not notice a thread
3930 switch due to internal events. Make sure we reverse to the
3931 user selected thread and frame after handling the event and
3932 running any breakpoint commands. */
3933 make_cleanup_restore_current_thread ();
3935 overlay_cache_invalid
= 1;
3936 /* Flush target cache before starting to handle each event. Target
3937 was running and cache could be stale. This is just a heuristic.
3938 Running threads may modify target memory, but we don't get any
3940 target_dcache_invalidate ();
3942 make_cleanup (restore_execution_direction
, &save_exec_dir
);
3943 execution_direction
= target_execution_direction ();
3945 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3946 target_can_async_p () ? TARGET_WNOHANG
: 0);
3949 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3951 /* If an error happens while handling the event, propagate GDB's
3952 knowledge of the executing state to the frontend/user running
3954 if (!target_is_non_stop_p ())
3955 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3957 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3959 /* Get executed before make_cleanup_restore_current_thread above to apply
3960 still for the thread which has thrown the exception. */
3961 make_bpstat_clear_actions_cleanup ();
3963 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3965 /* Now figure out what to do with the result of the result. */
3966 handle_inferior_event (ecs
);
3968 if (!ecs
->wait_some_more
)
3970 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3971 int should_stop
= 1;
3972 struct thread_info
*thr
= ecs
->event_thread
;
3973 int should_notify_stop
= 1;
3975 delete_just_stopped_threads_infrun_breakpoints ();
3979 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3981 if (thread_fsm
!= NULL
)
3982 should_stop
= thread_fsm_should_stop (thread_fsm
);
3991 clean_up_just_stopped_threads_fsms (ecs
);
3993 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3996 = thread_fsm_should_notify_stop (thr
->thread_fsm
);
3999 if (should_notify_stop
)
4003 /* We may not find an inferior if this was a process exit. */
4004 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
4005 proceeded
= normal_stop ();
4009 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
4016 /* No error, don't finish the thread states yet. */
4017 discard_cleanups (ts_old_chain
);
4019 /* Revert thread and frame. */
4020 do_cleanups (old_chain
);
4022 /* If a UI was in sync execution mode, and now isn't, restore its
4023 prompt (a synchronous execution command has finished, and we're
4024 ready for input). */
4025 all_uis_check_sync_execution_done ();
4028 && exec_done_display_p
4029 && (ptid_equal (inferior_ptid
, null_ptid
)
4030 || !is_running (inferior_ptid
)))
4031 printf_unfiltered (_("completed.\n"));
4034 /* Record the frame and location we're currently stepping through. */
4036 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
4038 struct thread_info
*tp
= inferior_thread ();
4040 tp
->control
.step_frame_id
= get_frame_id (frame
);
4041 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4043 tp
->current_symtab
= sal
.symtab
;
4044 tp
->current_line
= sal
.line
;
4047 /* Clear context switchable stepping state. */
4050 init_thread_stepping_state (struct thread_info
*tss
)
4052 tss
->stepped_breakpoint
= 0;
4053 tss
->stepping_over_breakpoint
= 0;
4054 tss
->stepping_over_watchpoint
= 0;
4055 tss
->step_after_step_resume_breakpoint
= 0;
4058 /* Set the cached copy of the last ptid/waitstatus. */
4061 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
4063 target_last_wait_ptid
= ptid
;
4064 target_last_waitstatus
= status
;
4067 /* Return the cached copy of the last pid/waitstatus returned by
4068 target_wait()/deprecated_target_wait_hook(). The data is actually
4069 cached by handle_inferior_event(), which gets called immediately
4070 after target_wait()/deprecated_target_wait_hook(). */
4073 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
4075 *ptidp
= target_last_wait_ptid
;
4076 *status
= target_last_waitstatus
;
4080 nullify_last_target_wait_ptid (void)
4082 target_last_wait_ptid
= minus_one_ptid
;
4085 /* Switch thread contexts. */
4088 context_switch (ptid_t ptid
)
4090 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
4092 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
4093 target_pid_to_str (inferior_ptid
));
4094 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
4095 target_pid_to_str (ptid
));
4098 switch_to_thread (ptid
);
4101 /* If the target can't tell whether we've hit breakpoints
4102 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4103 check whether that could have been caused by a breakpoint. If so,
4104 adjust the PC, per gdbarch_decr_pc_after_break. */
4107 adjust_pc_after_break (struct thread_info
*thread
,
4108 struct target_waitstatus
*ws
)
4110 struct regcache
*regcache
;
4111 struct gdbarch
*gdbarch
;
4112 struct address_space
*aspace
;
4113 CORE_ADDR breakpoint_pc
, decr_pc
;
4115 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4116 we aren't, just return.
4118 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4119 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4120 implemented by software breakpoints should be handled through the normal
4123 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4124 different signals (SIGILL or SIGEMT for instance), but it is less
4125 clear where the PC is pointing afterwards. It may not match
4126 gdbarch_decr_pc_after_break. I don't know any specific target that
4127 generates these signals at breakpoints (the code has been in GDB since at
4128 least 1992) so I can not guess how to handle them here.
4130 In earlier versions of GDB, a target with
4131 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4132 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4133 target with both of these set in GDB history, and it seems unlikely to be
4134 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4136 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4139 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4142 /* In reverse execution, when a breakpoint is hit, the instruction
4143 under it has already been de-executed. The reported PC always
4144 points at the breakpoint address, so adjusting it further would
4145 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4148 B1 0x08000000 : INSN1
4149 B2 0x08000001 : INSN2
4151 PC -> 0x08000003 : INSN4
4153 Say you're stopped at 0x08000003 as above. Reverse continuing
4154 from that point should hit B2 as below. Reading the PC when the
4155 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4156 been de-executed already.
4158 B1 0x08000000 : INSN1
4159 B2 PC -> 0x08000001 : INSN2
4163 We can't apply the same logic as for forward execution, because
4164 we would wrongly adjust the PC to 0x08000000, since there's a
4165 breakpoint at PC - 1. We'd then report a hit on B1, although
4166 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4168 if (execution_direction
== EXEC_REVERSE
)
4171 /* If the target can tell whether the thread hit a SW breakpoint,
4172 trust it. Targets that can tell also adjust the PC
4174 if (target_supports_stopped_by_sw_breakpoint ())
4177 /* Note that relying on whether a breakpoint is planted in memory to
4178 determine this can fail. E.g,. the breakpoint could have been
4179 removed since. Or the thread could have been told to step an
4180 instruction the size of a breakpoint instruction, and only
4181 _after_ was a breakpoint inserted at its address. */
4183 /* If this target does not decrement the PC after breakpoints, then
4184 we have nothing to do. */
4185 regcache
= get_thread_regcache (thread
->ptid
);
4186 gdbarch
= get_regcache_arch (regcache
);
4188 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4192 aspace
= get_regcache_aspace (regcache
);
4194 /* Find the location where (if we've hit a breakpoint) the
4195 breakpoint would be. */
4196 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4198 /* If the target can't tell whether a software breakpoint triggered,
4199 fallback to figuring it out based on breakpoints we think were
4200 inserted in the target, and on whether the thread was stepped or
4203 /* Check whether there actually is a software breakpoint inserted at
4206 If in non-stop mode, a race condition is possible where we've
4207 removed a breakpoint, but stop events for that breakpoint were
4208 already queued and arrive later. To suppress those spurious
4209 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4210 and retire them after a number of stop events are reported. Note
4211 this is an heuristic and can thus get confused. The real fix is
4212 to get the "stopped by SW BP and needs adjustment" info out of
4213 the target/kernel (and thus never reach here; see above). */
4214 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4215 || (target_is_non_stop_p ()
4216 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4218 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4220 if (record_full_is_used ())
4221 record_full_gdb_operation_disable_set ();
4223 /* When using hardware single-step, a SIGTRAP is reported for both
4224 a completed single-step and a software breakpoint. Need to
4225 differentiate between the two, as the latter needs adjusting
4226 but the former does not.
4228 The SIGTRAP can be due to a completed hardware single-step only if
4229 - we didn't insert software single-step breakpoints
4230 - this thread is currently being stepped
4232 If any of these events did not occur, we must have stopped due
4233 to hitting a software breakpoint, and have to back up to the
4236 As a special case, we could have hardware single-stepped a
4237 software breakpoint. In this case (prev_pc == breakpoint_pc),
4238 we also need to back up to the breakpoint address. */
4240 if (thread_has_single_step_breakpoints_set (thread
)
4241 || !currently_stepping (thread
)
4242 || (thread
->stepped_breakpoint
4243 && thread
->prev_pc
== breakpoint_pc
))
4244 regcache_write_pc (regcache
, breakpoint_pc
);
4246 do_cleanups (old_cleanups
);
4251 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4253 for (frame
= get_prev_frame (frame
);
4255 frame
= get_prev_frame (frame
))
4257 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4259 if (get_frame_type (frame
) != INLINE_FRAME
)
4266 /* Auxiliary function that handles syscall entry/return events.
4267 It returns 1 if the inferior should keep going (and GDB
4268 should ignore the event), or 0 if the event deserves to be
4272 handle_syscall_event (struct execution_control_state
*ecs
)
4274 struct regcache
*regcache
;
4277 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4278 context_switch (ecs
->ptid
);
4280 regcache
= get_thread_regcache (ecs
->ptid
);
4281 syscall_number
= ecs
->ws
.value
.syscall_number
;
4282 stop_pc
= regcache_read_pc (regcache
);
4284 if (catch_syscall_enabled () > 0
4285 && catching_syscall_number (syscall_number
) > 0)
4288 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4291 ecs
->event_thread
->control
.stop_bpstat
4292 = bpstat_stop_status (get_regcache_aspace (regcache
),
4293 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4295 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4297 /* Catchpoint hit. */
4302 /* If no catchpoint triggered for this, then keep going. */
4307 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4310 fill_in_stop_func (struct gdbarch
*gdbarch
,
4311 struct execution_control_state
*ecs
)
4313 if (!ecs
->stop_func_filled_in
)
4315 /* Don't care about return value; stop_func_start and stop_func_name
4316 will both be 0 if it doesn't work. */
4317 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4318 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4319 ecs
->stop_func_start
4320 += gdbarch_deprecated_function_start_offset (gdbarch
);
4322 if (gdbarch_skip_entrypoint_p (gdbarch
))
4323 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4324 ecs
->stop_func_start
);
4326 ecs
->stop_func_filled_in
= 1;
4331 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4333 static enum stop_kind
4334 get_inferior_stop_soon (ptid_t ptid
)
4336 struct inferior
*inf
= find_inferior_ptid (ptid
);
4338 gdb_assert (inf
!= NULL
);
4339 return inf
->control
.stop_soon
;
4342 /* Wait for one event. Store the resulting waitstatus in WS, and
4343 return the event ptid. */
4346 wait_one (struct target_waitstatus
*ws
)
4349 ptid_t wait_ptid
= minus_one_ptid
;
4351 overlay_cache_invalid
= 1;
4353 /* Flush target cache before starting to handle each event.
4354 Target was running and cache could be stale. This is just a
4355 heuristic. Running threads may modify target memory, but we
4356 don't get any event. */
4357 target_dcache_invalidate ();
4359 if (deprecated_target_wait_hook
)
4360 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4362 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4365 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4370 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4371 instead of the current thread. */
4372 #define THREAD_STOPPED_BY(REASON) \
4374 thread_stopped_by_ ## REASON (ptid_t ptid) \
4376 struct cleanup *old_chain; \
4379 old_chain = save_inferior_ptid (); \
4380 inferior_ptid = ptid; \
4382 res = target_stopped_by_ ## REASON (); \
4384 do_cleanups (old_chain); \
4389 /* Generate thread_stopped_by_watchpoint. */
4390 THREAD_STOPPED_BY (watchpoint
)
4391 /* Generate thread_stopped_by_sw_breakpoint. */
4392 THREAD_STOPPED_BY (sw_breakpoint
)
4393 /* Generate thread_stopped_by_hw_breakpoint. */
4394 THREAD_STOPPED_BY (hw_breakpoint
)
4396 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4399 switch_to_thread_cleanup (void *ptid_p
)
4401 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4403 switch_to_thread (ptid
);
4406 /* Save the thread's event and stop reason to process it later. */
4409 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4411 struct regcache
*regcache
;
4412 struct address_space
*aspace
;
4418 statstr
= target_waitstatus_to_string (ws
);
4419 fprintf_unfiltered (gdb_stdlog
,
4420 "infrun: saving status %s for %d.%ld.%ld\n",
4422 ptid_get_pid (tp
->ptid
),
4423 ptid_get_lwp (tp
->ptid
),
4424 ptid_get_tid (tp
->ptid
));
4428 /* Record for later. */
4429 tp
->suspend
.waitstatus
= *ws
;
4430 tp
->suspend
.waitstatus_pending_p
= 1;
4432 regcache
= get_thread_regcache (tp
->ptid
);
4433 aspace
= get_regcache_aspace (regcache
);
4435 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4436 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4438 CORE_ADDR pc
= regcache_read_pc (regcache
);
4440 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4442 if (thread_stopped_by_watchpoint (tp
->ptid
))
4444 tp
->suspend
.stop_reason
4445 = TARGET_STOPPED_BY_WATCHPOINT
;
4447 else if (target_supports_stopped_by_sw_breakpoint ()
4448 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4450 tp
->suspend
.stop_reason
4451 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4453 else if (target_supports_stopped_by_hw_breakpoint ()
4454 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4456 tp
->suspend
.stop_reason
4457 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4459 else if (!target_supports_stopped_by_hw_breakpoint ()
4460 && hardware_breakpoint_inserted_here_p (aspace
,
4463 tp
->suspend
.stop_reason
4464 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4466 else if (!target_supports_stopped_by_sw_breakpoint ()
4467 && software_breakpoint_inserted_here_p (aspace
,
4470 tp
->suspend
.stop_reason
4471 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4473 else if (!thread_has_single_step_breakpoints_set (tp
)
4474 && currently_stepping (tp
))
4476 tp
->suspend
.stop_reason
4477 = TARGET_STOPPED_BY_SINGLE_STEP
;
4482 /* A cleanup that disables thread create/exit events. */
4485 disable_thread_events (void *arg
)
4487 target_thread_events (0);
4493 stop_all_threads (void)
4495 /* We may need multiple passes to discover all threads. */
4499 struct cleanup
*old_chain
;
4501 gdb_assert (target_is_non_stop_p ());
4504 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4506 entry_ptid
= inferior_ptid
;
4507 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4509 target_thread_events (1);
4510 make_cleanup (disable_thread_events
, NULL
);
4512 /* Request threads to stop, and then wait for the stops. Because
4513 threads we already know about can spawn more threads while we're
4514 trying to stop them, and we only learn about new threads when we
4515 update the thread list, do this in a loop, and keep iterating
4516 until two passes find no threads that need to be stopped. */
4517 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4520 fprintf_unfiltered (gdb_stdlog
,
4521 "infrun: stop_all_threads, pass=%d, "
4522 "iterations=%d\n", pass
, iterations
);
4526 struct target_waitstatus ws
;
4528 struct thread_info
*t
;
4530 update_thread_list ();
4532 /* Go through all threads looking for threads that we need
4533 to tell the target to stop. */
4534 ALL_NON_EXITED_THREADS (t
)
4538 /* If already stopping, don't request a stop again.
4539 We just haven't seen the notification yet. */
4540 if (!t
->stop_requested
)
4543 fprintf_unfiltered (gdb_stdlog
,
4544 "infrun: %s executing, "
4546 target_pid_to_str (t
->ptid
));
4547 target_stop (t
->ptid
);
4548 t
->stop_requested
= 1;
4553 fprintf_unfiltered (gdb_stdlog
,
4554 "infrun: %s executing, "
4555 "already stopping\n",
4556 target_pid_to_str (t
->ptid
));
4559 if (t
->stop_requested
)
4565 fprintf_unfiltered (gdb_stdlog
,
4566 "infrun: %s not executing\n",
4567 target_pid_to_str (t
->ptid
));
4569 /* The thread may be not executing, but still be
4570 resumed with a pending status to process. */
4578 /* If we find new threads on the second iteration, restart
4579 over. We want to see two iterations in a row with all
4584 event_ptid
= wait_one (&ws
);
4585 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4587 /* All resumed threads exited. */
4589 else if (ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4590 || ws
.kind
== TARGET_WAITKIND_EXITED
4591 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4595 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4597 fprintf_unfiltered (gdb_stdlog
,
4598 "infrun: %s exited while "
4599 "stopping threads\n",
4600 target_pid_to_str (ptid
));
4605 struct inferior
*inf
;
4607 t
= find_thread_ptid (event_ptid
);
4609 t
= add_thread (event_ptid
);
4611 t
->stop_requested
= 0;
4614 t
->control
.may_range_step
= 0;
4616 /* This may be the first time we see the inferior report
4618 inf
= find_inferior_ptid (event_ptid
);
4619 if (inf
->needs_setup
)
4621 switch_to_thread_no_regs (t
);
4625 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4626 && ws
.value
.sig
== GDB_SIGNAL_0
)
4628 /* We caught the event that we intended to catch, so
4629 there's no event pending. */
4630 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4631 t
->suspend
.waitstatus_pending_p
= 0;
4633 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4635 /* Add it back to the step-over queue. */
4638 fprintf_unfiltered (gdb_stdlog
,
4639 "infrun: displaced-step of %s "
4640 "canceled: adding back to the "
4641 "step-over queue\n",
4642 target_pid_to_str (t
->ptid
));
4644 t
->control
.trap_expected
= 0;
4645 thread_step_over_chain_enqueue (t
);
4650 enum gdb_signal sig
;
4651 struct regcache
*regcache
;
4657 statstr
= target_waitstatus_to_string (&ws
);
4658 fprintf_unfiltered (gdb_stdlog
,
4659 "infrun: target_wait %s, saving "
4660 "status for %d.%ld.%ld\n",
4662 ptid_get_pid (t
->ptid
),
4663 ptid_get_lwp (t
->ptid
),
4664 ptid_get_tid (t
->ptid
));
4668 /* Record for later. */
4669 save_waitstatus (t
, &ws
);
4671 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4672 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4674 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4676 /* Add it back to the step-over queue. */
4677 t
->control
.trap_expected
= 0;
4678 thread_step_over_chain_enqueue (t
);
4681 regcache
= get_thread_regcache (t
->ptid
);
4682 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4686 fprintf_unfiltered (gdb_stdlog
,
4687 "infrun: saved stop_pc=%s for %s "
4688 "(currently_stepping=%d)\n",
4689 paddress (target_gdbarch (),
4690 t
->suspend
.stop_pc
),
4691 target_pid_to_str (t
->ptid
),
4692 currently_stepping (t
));
4699 do_cleanups (old_chain
);
4702 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4705 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4708 handle_no_resumed (struct execution_control_state
*ecs
)
4710 struct inferior
*inf
;
4711 struct thread_info
*thread
;
4713 if (target_can_async_p ())
4720 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4728 /* There were no unwaited-for children left in the target, but,
4729 we're not synchronously waiting for events either. Just
4733 fprintf_unfiltered (gdb_stdlog
,
4734 "infrun: TARGET_WAITKIND_NO_RESUMED "
4735 "(ignoring: bg)\n");
4736 prepare_to_wait (ecs
);
4741 /* Otherwise, if we were running a synchronous execution command, we
4742 may need to cancel it and give the user back the terminal.
4744 In non-stop mode, the target can't tell whether we've already
4745 consumed previous stop events, so it can end up sending us a
4746 no-resumed event like so:
4748 #0 - thread 1 is left stopped
4750 #1 - thread 2 is resumed and hits breakpoint
4751 -> TARGET_WAITKIND_STOPPED
4753 #2 - thread 3 is resumed and exits
4754 this is the last resumed thread, so
4755 -> TARGET_WAITKIND_NO_RESUMED
4757 #3 - gdb processes stop for thread 2 and decides to re-resume
4760 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4761 thread 2 is now resumed, so the event should be ignored.
4763 IOW, if the stop for thread 2 doesn't end a foreground command,
4764 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4765 event. But it could be that the event meant that thread 2 itself
4766 (or whatever other thread was the last resumed thread) exited.
4768 To address this we refresh the thread list and check whether we
4769 have resumed threads _now_. In the example above, this removes
4770 thread 3 from the thread list. If thread 2 was re-resumed, we
4771 ignore this event. If we find no thread resumed, then we cancel
4772 the synchronous command show "no unwaited-for " to the user. */
4773 update_thread_list ();
4775 ALL_NON_EXITED_THREADS (thread
)
4777 if (thread
->executing
4778 || thread
->suspend
.waitstatus_pending_p
)
4780 /* There were no unwaited-for children left in the target at
4781 some point, but there are now. Just ignore. */
4783 fprintf_unfiltered (gdb_stdlog
,
4784 "infrun: TARGET_WAITKIND_NO_RESUMED "
4785 "(ignoring: found resumed)\n");
4786 prepare_to_wait (ecs
);
4791 /* Note however that we may find no resumed thread because the whole
4792 process exited meanwhile (thus updating the thread list results
4793 in an empty thread list). In this case we know we'll be getting
4794 a process exit event shortly. */
4800 thread
= any_live_thread_of_process (inf
->pid
);
4804 fprintf_unfiltered (gdb_stdlog
,
4805 "infrun: TARGET_WAITKIND_NO_RESUMED "
4806 "(expect process exit)\n");
4807 prepare_to_wait (ecs
);
4812 /* Go ahead and report the event. */
4816 /* Given an execution control state that has been freshly filled in by
4817 an event from the inferior, figure out what it means and take
4820 The alternatives are:
4822 1) stop_waiting and return; to really stop and return to the
4825 2) keep_going and return; to wait for the next event (set
4826 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4830 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4832 enum stop_kind stop_soon
;
4834 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4836 /* We had an event in the inferior, but we are not interested in
4837 handling it at this level. The lower layers have already
4838 done what needs to be done, if anything.
4840 One of the possible circumstances for this is when the
4841 inferior produces output for the console. The inferior has
4842 not stopped, and we are ignoring the event. Another possible
4843 circumstance is any event which the lower level knows will be
4844 reported multiple times without an intervening resume. */
4846 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4847 prepare_to_wait (ecs
);
4851 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4854 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4855 prepare_to_wait (ecs
);
4859 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4860 && handle_no_resumed (ecs
))
4863 /* Cache the last pid/waitstatus. */
4864 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4866 /* Always clear state belonging to the previous time we stopped. */
4867 stop_stack_dummy
= STOP_NONE
;
4869 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4871 /* No unwaited-for children left. IOW, all resumed children
4874 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4876 stop_print_frame
= 0;
4881 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4882 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4884 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4885 /* If it's a new thread, add it to the thread database. */
4886 if (ecs
->event_thread
== NULL
)
4887 ecs
->event_thread
= add_thread (ecs
->ptid
);
4889 /* Disable range stepping. If the next step request could use a
4890 range, this will be end up re-enabled then. */
4891 ecs
->event_thread
->control
.may_range_step
= 0;
4894 /* Dependent on valid ECS->EVENT_THREAD. */
4895 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4897 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4898 reinit_frame_cache ();
4900 breakpoint_retire_moribund ();
4902 /* First, distinguish signals caused by the debugger from signals
4903 that have to do with the program's own actions. Note that
4904 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4905 on the operating system version. Here we detect when a SIGILL or
4906 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4907 something similar for SIGSEGV, since a SIGSEGV will be generated
4908 when we're trying to execute a breakpoint instruction on a
4909 non-executable stack. This happens for call dummy breakpoints
4910 for architectures like SPARC that place call dummies on the
4912 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4913 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4914 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4915 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4917 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4919 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
4920 regcache_read_pc (regcache
)))
4923 fprintf_unfiltered (gdb_stdlog
,
4924 "infrun: Treating signal as SIGTRAP\n");
4925 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4929 /* Mark the non-executing threads accordingly. In all-stop, all
4930 threads of all processes are stopped when we get any event
4931 reported. In non-stop mode, only the event thread stops. */
4935 if (!target_is_non_stop_p ())
4936 mark_ptid
= minus_one_ptid
;
4937 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4938 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4940 /* If we're handling a process exit in non-stop mode, even
4941 though threads haven't been deleted yet, one would think
4942 that there is nothing to do, as threads of the dead process
4943 will be soon deleted, and threads of any other process were
4944 left running. However, on some targets, threads survive a
4945 process exit event. E.g., for the "checkpoint" command,
4946 when the current checkpoint/fork exits, linux-fork.c
4947 automatically switches to another fork from within
4948 target_mourn_inferior, by associating the same
4949 inferior/thread to another fork. We haven't mourned yet at
4950 this point, but we must mark any threads left in the
4951 process as not-executing so that finish_thread_state marks
4952 them stopped (in the user's perspective) if/when we present
4953 the stop to the user. */
4954 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4957 mark_ptid
= ecs
->ptid
;
4959 set_executing (mark_ptid
, 0);
4961 /* Likewise the resumed flag. */
4962 set_resumed (mark_ptid
, 0);
4965 switch (ecs
->ws
.kind
)
4967 case TARGET_WAITKIND_LOADED
:
4969 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4970 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4971 context_switch (ecs
->ptid
);
4972 /* Ignore gracefully during startup of the inferior, as it might
4973 be the shell which has just loaded some objects, otherwise
4974 add the symbols for the newly loaded objects. Also ignore at
4975 the beginning of an attach or remote session; we will query
4976 the full list of libraries once the connection is
4979 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4980 if (stop_soon
== NO_STOP_QUIETLY
)
4982 struct regcache
*regcache
;
4984 regcache
= get_thread_regcache (ecs
->ptid
);
4986 handle_solib_event ();
4988 ecs
->event_thread
->control
.stop_bpstat
4989 = bpstat_stop_status (get_regcache_aspace (regcache
),
4990 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4992 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4994 /* A catchpoint triggered. */
4995 process_event_stop_test (ecs
);
4999 /* If requested, stop when the dynamic linker notifies
5000 gdb of events. This allows the user to get control
5001 and place breakpoints in initializer routines for
5002 dynamically loaded objects (among other things). */
5003 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5004 if (stop_on_solib_events
)
5006 /* Make sure we print "Stopped due to solib-event" in
5008 stop_print_frame
= 1;
5015 /* If we are skipping through a shell, or through shared library
5016 loading that we aren't interested in, resume the program. If
5017 we're running the program normally, also resume. */
5018 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5020 /* Loading of shared libraries might have changed breakpoint
5021 addresses. Make sure new breakpoints are inserted. */
5022 if (stop_soon
== NO_STOP_QUIETLY
)
5023 insert_breakpoints ();
5024 resume (GDB_SIGNAL_0
);
5025 prepare_to_wait (ecs
);
5029 /* But stop if we're attaching or setting up a remote
5031 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5032 || stop_soon
== STOP_QUIETLY_REMOTE
)
5035 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5040 internal_error (__FILE__
, __LINE__
,
5041 _("unhandled stop_soon: %d"), (int) stop_soon
);
5043 case TARGET_WAITKIND_SPURIOUS
:
5045 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
5046 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5047 context_switch (ecs
->ptid
);
5048 resume (GDB_SIGNAL_0
);
5049 prepare_to_wait (ecs
);
5052 case TARGET_WAITKIND_THREAD_CREATED
:
5054 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
5055 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5056 context_switch (ecs
->ptid
);
5057 if (!switch_back_to_stepped_thread (ecs
))
5061 case TARGET_WAITKIND_EXITED
:
5062 case TARGET_WAITKIND_SIGNALLED
:
5065 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5066 fprintf_unfiltered (gdb_stdlog
,
5067 "infrun: TARGET_WAITKIND_EXITED\n");
5069 fprintf_unfiltered (gdb_stdlog
,
5070 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5073 inferior_ptid
= ecs
->ptid
;
5074 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
5075 set_current_program_space (current_inferior ()->pspace
);
5076 handle_vfork_child_exec_or_exit (0);
5077 target_terminal_ours (); /* Must do this before mourn anyway. */
5079 /* Clearing any previous state of convenience variables. */
5080 clear_exit_convenience_vars ();
5082 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5084 /* Record the exit code in the convenience variable $_exitcode, so
5085 that the user can inspect this again later. */
5086 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5087 (LONGEST
) ecs
->ws
.value
.integer
);
5089 /* Also record this in the inferior itself. */
5090 current_inferior ()->has_exit_code
= 1;
5091 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5093 /* Support the --return-child-result option. */
5094 return_child_result_value
= ecs
->ws
.value
.integer
;
5096 observer_notify_exited (ecs
->ws
.value
.integer
);
5100 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5101 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5103 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5105 /* Set the value of the internal variable $_exitsignal,
5106 which holds the signal uncaught by the inferior. */
5107 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5108 gdbarch_gdb_signal_to_target (gdbarch
,
5109 ecs
->ws
.value
.sig
));
5113 /* We don't have access to the target's method used for
5114 converting between signal numbers (GDB's internal
5115 representation <-> target's representation).
5116 Therefore, we cannot do a good job at displaying this
5117 information to the user. It's better to just warn
5118 her about it (if infrun debugging is enabled), and
5121 fprintf_filtered (gdb_stdlog
, _("\
5122 Cannot fill $_exitsignal with the correct signal number.\n"));
5125 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
5128 gdb_flush (gdb_stdout
);
5129 target_mourn_inferior ();
5130 stop_print_frame
= 0;
5134 /* The following are the only cases in which we keep going;
5135 the above cases end in a continue or goto. */
5136 case TARGET_WAITKIND_FORKED
:
5137 case TARGET_WAITKIND_VFORKED
:
5140 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5141 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
5143 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
5146 /* Check whether the inferior is displaced stepping. */
5148 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5149 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5151 /* If checking displaced stepping is supported, and thread
5152 ecs->ptid is displaced stepping. */
5153 if (displaced_step_in_progress_thread (ecs
->ptid
))
5155 struct inferior
*parent_inf
5156 = find_inferior_ptid (ecs
->ptid
);
5157 struct regcache
*child_regcache
;
5158 CORE_ADDR parent_pc
;
5160 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5161 indicating that the displaced stepping of syscall instruction
5162 has been done. Perform cleanup for parent process here. Note
5163 that this operation also cleans up the child process for vfork,
5164 because their pages are shared. */
5165 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
5166 /* Start a new step-over in another thread if there's one
5170 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5172 struct displaced_step_inferior_state
*displaced
5173 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
5175 /* Restore scratch pad for child process. */
5176 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
5179 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5180 the child's PC is also within the scratchpad. Set the child's PC
5181 to the parent's PC value, which has already been fixed up.
5182 FIXME: we use the parent's aspace here, although we're touching
5183 the child, because the child hasn't been added to the inferior
5184 list yet at this point. */
5187 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
5189 parent_inf
->aspace
);
5190 /* Read PC value of parent process. */
5191 parent_pc
= regcache_read_pc (regcache
);
5193 if (debug_displaced
)
5194 fprintf_unfiltered (gdb_stdlog
,
5195 "displaced: write child pc from %s to %s\n",
5197 regcache_read_pc (child_regcache
)),
5198 paddress (gdbarch
, parent_pc
));
5200 regcache_write_pc (child_regcache
, parent_pc
);
5204 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5205 context_switch (ecs
->ptid
);
5207 /* Immediately detach breakpoints from the child before there's
5208 any chance of letting the user delete breakpoints from the
5209 breakpoint lists. If we don't do this early, it's easy to
5210 leave left over traps in the child, vis: "break foo; catch
5211 fork; c; <fork>; del; c; <child calls foo>". We only follow
5212 the fork on the last `continue', and by that time the
5213 breakpoint at "foo" is long gone from the breakpoint table.
5214 If we vforked, then we don't need to unpatch here, since both
5215 parent and child are sharing the same memory pages; we'll
5216 need to unpatch at follow/detach time instead to be certain
5217 that new breakpoints added between catchpoint hit time and
5218 vfork follow are detached. */
5219 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5221 /* This won't actually modify the breakpoint list, but will
5222 physically remove the breakpoints from the child. */
5223 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5226 delete_just_stopped_threads_single_step_breakpoints ();
5228 /* In case the event is caught by a catchpoint, remember that
5229 the event is to be followed at the next resume of the thread,
5230 and not immediately. */
5231 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5233 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5235 ecs
->event_thread
->control
.stop_bpstat
5236 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5237 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5239 /* If no catchpoint triggered for this, then keep going. Note
5240 that we're interested in knowing the bpstat actually causes a
5241 stop, not just if it may explain the signal. Software
5242 watchpoints, for example, always appear in the bpstat. */
5243 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5249 = (follow_fork_mode_string
== follow_fork_mode_child
);
5251 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5253 should_resume
= follow_fork ();
5256 child
= ecs
->ws
.value
.related_pid
;
5258 /* At this point, the parent is marked running, and the
5259 child is marked stopped. */
5261 /* If not resuming the parent, mark it stopped. */
5262 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5263 set_running (parent
, 0);
5265 /* If resuming the child, mark it running. */
5266 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5267 set_running (child
, 1);
5269 /* In non-stop mode, also resume the other branch. */
5270 if (!detach_fork
&& (non_stop
5271 || (sched_multi
&& target_is_non_stop_p ())))
5274 switch_to_thread (parent
);
5276 switch_to_thread (child
);
5278 ecs
->event_thread
= inferior_thread ();
5279 ecs
->ptid
= inferior_ptid
;
5284 switch_to_thread (child
);
5286 switch_to_thread (parent
);
5288 ecs
->event_thread
= inferior_thread ();
5289 ecs
->ptid
= inferior_ptid
;
5297 process_event_stop_test (ecs
);
5300 case TARGET_WAITKIND_VFORK_DONE
:
5301 /* Done with the shared memory region. Re-insert breakpoints in
5302 the parent, and keep going. */
5305 fprintf_unfiltered (gdb_stdlog
,
5306 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5308 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5309 context_switch (ecs
->ptid
);
5311 current_inferior ()->waiting_for_vfork_done
= 0;
5312 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5313 /* This also takes care of reinserting breakpoints in the
5314 previously locked inferior. */
5318 case TARGET_WAITKIND_EXECD
:
5320 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5322 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5323 context_switch (ecs
->ptid
);
5325 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5327 /* Do whatever is necessary to the parent branch of the vfork. */
5328 handle_vfork_child_exec_or_exit (1);
5330 /* This causes the eventpoints and symbol table to be reset.
5331 Must do this now, before trying to determine whether to
5333 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5335 /* In follow_exec we may have deleted the original thread and
5336 created a new one. Make sure that the event thread is the
5337 execd thread for that case (this is a nop otherwise). */
5338 ecs
->event_thread
= inferior_thread ();
5340 ecs
->event_thread
->control
.stop_bpstat
5341 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5342 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5344 /* Note that this may be referenced from inside
5345 bpstat_stop_status above, through inferior_has_execd. */
5346 xfree (ecs
->ws
.value
.execd_pathname
);
5347 ecs
->ws
.value
.execd_pathname
= NULL
;
5349 /* If no catchpoint triggered for this, then keep going. */
5350 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5352 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5356 process_event_stop_test (ecs
);
5359 /* Be careful not to try to gather much state about a thread
5360 that's in a syscall. It's frequently a losing proposition. */
5361 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5363 fprintf_unfiltered (gdb_stdlog
,
5364 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5365 /* Getting the current syscall number. */
5366 if (handle_syscall_event (ecs
) == 0)
5367 process_event_stop_test (ecs
);
5370 /* Before examining the threads further, step this thread to
5371 get it entirely out of the syscall. (We get notice of the
5372 event when the thread is just on the verge of exiting a
5373 syscall. Stepping one instruction seems to get it back
5375 case TARGET_WAITKIND_SYSCALL_RETURN
:
5377 fprintf_unfiltered (gdb_stdlog
,
5378 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5379 if (handle_syscall_event (ecs
) == 0)
5380 process_event_stop_test (ecs
);
5383 case TARGET_WAITKIND_STOPPED
:
5385 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5386 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5387 handle_signal_stop (ecs
);
5390 case TARGET_WAITKIND_NO_HISTORY
:
5392 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5393 /* Reverse execution: target ran out of history info. */
5395 /* Switch to the stopped thread. */
5396 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5397 context_switch (ecs
->ptid
);
5399 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5401 delete_just_stopped_threads_single_step_breakpoints ();
5402 stop_pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
5403 observer_notify_no_history ();
5409 /* A wrapper around handle_inferior_event_1, which also makes sure
5410 that all temporary struct value objects that were created during
5411 the handling of the event get deleted at the end. */
5414 handle_inferior_event (struct execution_control_state
*ecs
)
5416 struct value
*mark
= value_mark ();
5418 handle_inferior_event_1 (ecs
);
5419 /* Purge all temporary values created during the event handling,
5420 as it could be a long time before we return to the command level
5421 where such values would otherwise be purged. */
5422 value_free_to_mark (mark
);
5425 /* Restart threads back to what they were trying to do back when we
5426 paused them for an in-line step-over. The EVENT_THREAD thread is
5430 restart_threads (struct thread_info
*event_thread
)
5432 struct thread_info
*tp
;
5434 /* In case the instruction just stepped spawned a new thread. */
5435 update_thread_list ();
5437 ALL_NON_EXITED_THREADS (tp
)
5439 if (tp
== event_thread
)
5442 fprintf_unfiltered (gdb_stdlog
,
5443 "infrun: restart threads: "
5444 "[%s] is event thread\n",
5445 target_pid_to_str (tp
->ptid
));
5449 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5452 fprintf_unfiltered (gdb_stdlog
,
5453 "infrun: restart threads: "
5454 "[%s] not meant to be running\n",
5455 target_pid_to_str (tp
->ptid
));
5462 fprintf_unfiltered (gdb_stdlog
,
5463 "infrun: restart threads: [%s] resumed\n",
5464 target_pid_to_str (tp
->ptid
));
5465 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5469 if (thread_is_in_step_over_chain (tp
))
5472 fprintf_unfiltered (gdb_stdlog
,
5473 "infrun: restart threads: "
5474 "[%s] needs step-over\n",
5475 target_pid_to_str (tp
->ptid
));
5476 gdb_assert (!tp
->resumed
);
5481 if (tp
->suspend
.waitstatus_pending_p
)
5484 fprintf_unfiltered (gdb_stdlog
,
5485 "infrun: restart threads: "
5486 "[%s] has pending status\n",
5487 target_pid_to_str (tp
->ptid
));
5492 /* If some thread needs to start a step-over at this point, it
5493 should still be in the step-over queue, and thus skipped
5495 if (thread_still_needs_step_over (tp
))
5497 internal_error (__FILE__
, __LINE__
,
5498 "thread [%s] needs a step-over, but not in "
5499 "step-over queue\n",
5500 target_pid_to_str (tp
->ptid
));
5503 if (currently_stepping (tp
))
5506 fprintf_unfiltered (gdb_stdlog
,
5507 "infrun: restart threads: [%s] was stepping\n",
5508 target_pid_to_str (tp
->ptid
));
5509 keep_going_stepped_thread (tp
);
5513 struct execution_control_state ecss
;
5514 struct execution_control_state
*ecs
= &ecss
;
5517 fprintf_unfiltered (gdb_stdlog
,
5518 "infrun: restart threads: [%s] continuing\n",
5519 target_pid_to_str (tp
->ptid
));
5520 reset_ecs (ecs
, tp
);
5521 switch_to_thread (tp
->ptid
);
5522 keep_going_pass_signal (ecs
);
5527 /* Callback for iterate_over_threads. Find a resumed thread that has
5528 a pending waitstatus. */
5531 resumed_thread_with_pending_status (struct thread_info
*tp
,
5535 && tp
->suspend
.waitstatus_pending_p
);
5538 /* Called when we get an event that may finish an in-line or
5539 out-of-line (displaced stepping) step-over started previously.
5540 Return true if the event is processed and we should go back to the
5541 event loop; false if the caller should continue processing the
5545 finish_step_over (struct execution_control_state
*ecs
)
5547 int had_step_over_info
;
5549 displaced_step_fixup (ecs
->ptid
,
5550 ecs
->event_thread
->suspend
.stop_signal
);
5552 had_step_over_info
= step_over_info_valid_p ();
5554 if (had_step_over_info
)
5556 /* If we're stepping over a breakpoint with all threads locked,
5557 then only the thread that was stepped should be reporting
5559 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5561 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5562 clear_step_over_info ();
5565 if (!target_is_non_stop_p ())
5568 /* Start a new step-over in another thread if there's one that
5572 /* If we were stepping over a breakpoint before, and haven't started
5573 a new in-line step-over sequence, then restart all other threads
5574 (except the event thread). We can't do this in all-stop, as then
5575 e.g., we wouldn't be able to issue any other remote packet until
5576 these other threads stop. */
5577 if (had_step_over_info
&& !step_over_info_valid_p ())
5579 struct thread_info
*pending
;
5581 /* If we only have threads with pending statuses, the restart
5582 below won't restart any thread and so nothing re-inserts the
5583 breakpoint we just stepped over. But we need it inserted
5584 when we later process the pending events, otherwise if
5585 another thread has a pending event for this breakpoint too,
5586 we'd discard its event (because the breakpoint that
5587 originally caused the event was no longer inserted). */
5588 context_switch (ecs
->ptid
);
5589 insert_breakpoints ();
5591 restart_threads (ecs
->event_thread
);
5593 /* If we have events pending, go through handle_inferior_event
5594 again, picking up a pending event at random. This avoids
5595 thread starvation. */
5597 /* But not if we just stepped over a watchpoint in order to let
5598 the instruction execute so we can evaluate its expression.
5599 The set of watchpoints that triggered is recorded in the
5600 breakpoint objects themselves (see bp->watchpoint_triggered).
5601 If we processed another event first, that other event could
5602 clobber this info. */
5603 if (ecs
->event_thread
->stepping_over_watchpoint
)
5606 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5608 if (pending
!= NULL
)
5610 struct thread_info
*tp
= ecs
->event_thread
;
5611 struct regcache
*regcache
;
5615 fprintf_unfiltered (gdb_stdlog
,
5616 "infrun: found resumed threads with "
5617 "pending events, saving status\n");
5620 gdb_assert (pending
!= tp
);
5622 /* Record the event thread's event for later. */
5623 save_waitstatus (tp
, &ecs
->ws
);
5624 /* This was cleared early, by handle_inferior_event. Set it
5625 so this pending event is considered by
5629 gdb_assert (!tp
->executing
);
5631 regcache
= get_thread_regcache (tp
->ptid
);
5632 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5636 fprintf_unfiltered (gdb_stdlog
,
5637 "infrun: saved stop_pc=%s for %s "
5638 "(currently_stepping=%d)\n",
5639 paddress (target_gdbarch (),
5640 tp
->suspend
.stop_pc
),
5641 target_pid_to_str (tp
->ptid
),
5642 currently_stepping (tp
));
5645 /* This in-line step-over finished; clear this so we won't
5646 start a new one. This is what handle_signal_stop would
5647 do, if we returned false. */
5648 tp
->stepping_over_breakpoint
= 0;
5650 /* Wake up the event loop again. */
5651 mark_async_event_handler (infrun_async_inferior_event_token
);
5653 prepare_to_wait (ecs
);
5661 /* Come here when the program has stopped with a signal. */
5664 handle_signal_stop (struct execution_control_state
*ecs
)
5666 struct frame_info
*frame
;
5667 struct gdbarch
*gdbarch
;
5668 int stopped_by_watchpoint
;
5669 enum stop_kind stop_soon
;
5672 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5674 /* Do we need to clean up the state of a thread that has
5675 completed a displaced single-step? (Doing so usually affects
5676 the PC, so do it here, before we set stop_pc.) */
5677 if (finish_step_over (ecs
))
5680 /* If we either finished a single-step or hit a breakpoint, but
5681 the user wanted this thread to be stopped, pretend we got a
5682 SIG0 (generic unsignaled stop). */
5683 if (ecs
->event_thread
->stop_requested
5684 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5685 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5687 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5691 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5692 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5693 struct cleanup
*old_chain
= save_inferior_ptid ();
5695 inferior_ptid
= ecs
->ptid
;
5697 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5698 paddress (gdbarch
, stop_pc
));
5699 if (target_stopped_by_watchpoint ())
5703 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5705 if (target_stopped_data_address (¤t_target
, &addr
))
5706 fprintf_unfiltered (gdb_stdlog
,
5707 "infrun: stopped data address = %s\n",
5708 paddress (gdbarch
, addr
));
5710 fprintf_unfiltered (gdb_stdlog
,
5711 "infrun: (no data address available)\n");
5714 do_cleanups (old_chain
);
5717 /* This is originated from start_remote(), start_inferior() and
5718 shared libraries hook functions. */
5719 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5720 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5722 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5723 context_switch (ecs
->ptid
);
5725 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5726 stop_print_frame
= 1;
5731 /* This originates from attach_command(). We need to overwrite
5732 the stop_signal here, because some kernels don't ignore a
5733 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5734 See more comments in inferior.h. On the other hand, if we
5735 get a non-SIGSTOP, report it to the user - assume the backend
5736 will handle the SIGSTOP if it should show up later.
5738 Also consider that the attach is complete when we see a
5739 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5740 target extended-remote report it instead of a SIGSTOP
5741 (e.g. gdbserver). We already rely on SIGTRAP being our
5742 signal, so this is no exception.
5744 Also consider that the attach is complete when we see a
5745 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5746 the target to stop all threads of the inferior, in case the
5747 low level attach operation doesn't stop them implicitly. If
5748 they weren't stopped implicitly, then the stub will report a
5749 GDB_SIGNAL_0, meaning: stopped for no particular reason
5750 other than GDB's request. */
5751 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5752 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5753 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5754 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5756 stop_print_frame
= 1;
5758 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5762 /* See if something interesting happened to the non-current thread. If
5763 so, then switch to that thread. */
5764 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5767 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5769 context_switch (ecs
->ptid
);
5771 if (deprecated_context_hook
)
5772 deprecated_context_hook (ptid_to_global_thread_id (ecs
->ptid
));
5775 /* At this point, get hold of the now-current thread's frame. */
5776 frame
= get_current_frame ();
5777 gdbarch
= get_frame_arch (frame
);
5779 /* Pull the single step breakpoints out of the target. */
5780 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5782 struct regcache
*regcache
;
5783 struct address_space
*aspace
;
5786 regcache
= get_thread_regcache (ecs
->ptid
);
5787 aspace
= get_regcache_aspace (regcache
);
5788 pc
= regcache_read_pc (regcache
);
5790 /* However, before doing so, if this single-step breakpoint was
5791 actually for another thread, set this thread up for moving
5793 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5796 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5800 fprintf_unfiltered (gdb_stdlog
,
5801 "infrun: [%s] hit another thread's "
5802 "single-step breakpoint\n",
5803 target_pid_to_str (ecs
->ptid
));
5805 ecs
->hit_singlestep_breakpoint
= 1;
5812 fprintf_unfiltered (gdb_stdlog
,
5813 "infrun: [%s] hit its "
5814 "single-step breakpoint\n",
5815 target_pid_to_str (ecs
->ptid
));
5819 delete_just_stopped_threads_single_step_breakpoints ();
5821 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5822 && ecs
->event_thread
->control
.trap_expected
5823 && ecs
->event_thread
->stepping_over_watchpoint
)
5824 stopped_by_watchpoint
= 0;
5826 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5828 /* If necessary, step over this watchpoint. We'll be back to display
5830 if (stopped_by_watchpoint
5831 && (target_have_steppable_watchpoint
5832 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5834 /* At this point, we are stopped at an instruction which has
5835 attempted to write to a piece of memory under control of
5836 a watchpoint. The instruction hasn't actually executed
5837 yet. If we were to evaluate the watchpoint expression
5838 now, we would get the old value, and therefore no change
5839 would seem to have occurred.
5841 In order to make watchpoints work `right', we really need
5842 to complete the memory write, and then evaluate the
5843 watchpoint expression. We do this by single-stepping the
5846 It may not be necessary to disable the watchpoint to step over
5847 it. For example, the PA can (with some kernel cooperation)
5848 single step over a watchpoint without disabling the watchpoint.
5850 It is far more common to need to disable a watchpoint to step
5851 the inferior over it. If we have non-steppable watchpoints,
5852 we must disable the current watchpoint; it's simplest to
5853 disable all watchpoints.
5855 Any breakpoint at PC must also be stepped over -- if there's
5856 one, it will have already triggered before the watchpoint
5857 triggered, and we either already reported it to the user, or
5858 it didn't cause a stop and we called keep_going. In either
5859 case, if there was a breakpoint at PC, we must be trying to
5861 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5866 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5867 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5868 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5869 ecs
->event_thread
->control
.stop_step
= 0;
5870 stop_print_frame
= 1;
5871 stopped_by_random_signal
= 0;
5873 /* Hide inlined functions starting here, unless we just performed stepi or
5874 nexti. After stepi and nexti, always show the innermost frame (not any
5875 inline function call sites). */
5876 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5878 struct address_space
*aspace
=
5879 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
5881 /* skip_inline_frames is expensive, so we avoid it if we can
5882 determine that the address is one where functions cannot have
5883 been inlined. This improves performance with inferiors that
5884 load a lot of shared libraries, because the solib event
5885 breakpoint is defined as the address of a function (i.e. not
5886 inline). Note that we have to check the previous PC as well
5887 as the current one to catch cases when we have just
5888 single-stepped off a breakpoint prior to reinstating it.
5889 Note that we're assuming that the code we single-step to is
5890 not inline, but that's not definitive: there's nothing
5891 preventing the event breakpoint function from containing
5892 inlined code, and the single-step ending up there. If the
5893 user had set a breakpoint on that inlined code, the missing
5894 skip_inline_frames call would break things. Fortunately
5895 that's an extremely unlikely scenario. */
5896 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5897 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5898 && ecs
->event_thread
->control
.trap_expected
5899 && pc_at_non_inline_function (aspace
,
5900 ecs
->event_thread
->prev_pc
,
5903 skip_inline_frames (ecs
->ptid
);
5905 /* Re-fetch current thread's frame in case that invalidated
5907 frame
= get_current_frame ();
5908 gdbarch
= get_frame_arch (frame
);
5912 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5913 && ecs
->event_thread
->control
.trap_expected
5914 && gdbarch_single_step_through_delay_p (gdbarch
)
5915 && currently_stepping (ecs
->event_thread
))
5917 /* We're trying to step off a breakpoint. Turns out that we're
5918 also on an instruction that needs to be stepped multiple
5919 times before it's been fully executing. E.g., architectures
5920 with a delay slot. It needs to be stepped twice, once for
5921 the instruction and once for the delay slot. */
5922 int step_through_delay
5923 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5925 if (debug_infrun
&& step_through_delay
)
5926 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5927 if (ecs
->event_thread
->control
.step_range_end
== 0
5928 && step_through_delay
)
5930 /* The user issued a continue when stopped at a breakpoint.
5931 Set up for another trap and get out of here. */
5932 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5936 else if (step_through_delay
)
5938 /* The user issued a step when stopped at a breakpoint.
5939 Maybe we should stop, maybe we should not - the delay
5940 slot *might* correspond to a line of source. In any
5941 case, don't decide that here, just set
5942 ecs->stepping_over_breakpoint, making sure we
5943 single-step again before breakpoints are re-inserted. */
5944 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5948 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5949 handles this event. */
5950 ecs
->event_thread
->control
.stop_bpstat
5951 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5952 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5954 /* Following in case break condition called a
5956 stop_print_frame
= 1;
5958 /* This is where we handle "moribund" watchpoints. Unlike
5959 software breakpoints traps, hardware watchpoint traps are
5960 always distinguishable from random traps. If no high-level
5961 watchpoint is associated with the reported stop data address
5962 anymore, then the bpstat does not explain the signal ---
5963 simply make sure to ignore it if `stopped_by_watchpoint' is
5967 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5968 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5970 && stopped_by_watchpoint
)
5971 fprintf_unfiltered (gdb_stdlog
,
5972 "infrun: no user watchpoint explains "
5973 "watchpoint SIGTRAP, ignoring\n");
5975 /* NOTE: cagney/2003-03-29: These checks for a random signal
5976 at one stage in the past included checks for an inferior
5977 function call's call dummy's return breakpoint. The original
5978 comment, that went with the test, read:
5980 ``End of a stack dummy. Some systems (e.g. Sony news) give
5981 another signal besides SIGTRAP, so check here as well as
5984 If someone ever tries to get call dummys on a
5985 non-executable stack to work (where the target would stop
5986 with something like a SIGSEGV), then those tests might need
5987 to be re-instated. Given, however, that the tests were only
5988 enabled when momentary breakpoints were not being used, I
5989 suspect that it won't be the case.
5991 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5992 be necessary for call dummies on a non-executable stack on
5995 /* See if the breakpoints module can explain the signal. */
5997 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5998 ecs
->event_thread
->suspend
.stop_signal
);
6000 /* Maybe this was a trap for a software breakpoint that has since
6002 if (random_signal
&& target_stopped_by_sw_breakpoint ())
6004 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
6006 struct regcache
*regcache
;
6009 /* Re-adjust PC to what the program would see if GDB was not
6011 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
6012 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6015 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
6017 if (record_full_is_used ())
6018 record_full_gdb_operation_disable_set ();
6020 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
6022 do_cleanups (old_cleanups
);
6027 /* A delayed software breakpoint event. Ignore the trap. */
6029 fprintf_unfiltered (gdb_stdlog
,
6030 "infrun: delayed software breakpoint "
6031 "trap, ignoring\n");
6036 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6037 has since been removed. */
6038 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6040 /* A delayed hardware breakpoint event. Ignore the trap. */
6042 fprintf_unfiltered (gdb_stdlog
,
6043 "infrun: delayed hardware breakpoint/watchpoint "
6044 "trap, ignoring\n");
6048 /* If not, perhaps stepping/nexting can. */
6050 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6051 && currently_stepping (ecs
->event_thread
));
6053 /* Perhaps the thread hit a single-step breakpoint of _another_
6054 thread. Single-step breakpoints are transparent to the
6055 breakpoints module. */
6057 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6059 /* No? Perhaps we got a moribund watchpoint. */
6061 random_signal
= !stopped_by_watchpoint
;
6063 /* For the program's own signals, act according to
6064 the signal handling tables. */
6068 /* Signal not for debugging purposes. */
6069 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
6070 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6073 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
6074 gdb_signal_to_symbol_string (stop_signal
));
6076 stopped_by_random_signal
= 1;
6078 /* Always stop on signals if we're either just gaining control
6079 of the program, or the user explicitly requested this thread
6080 to remain stopped. */
6081 if (stop_soon
!= NO_STOP_QUIETLY
6082 || ecs
->event_thread
->stop_requested
6084 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
6090 /* Notify observers the signal has "handle print" set. Note we
6091 returned early above if stopping; normal_stop handles the
6092 printing in that case. */
6093 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6095 /* The signal table tells us to print about this signal. */
6096 target_terminal_ours_for_output ();
6097 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
6098 target_terminal_inferior ();
6101 /* Clear the signal if it should not be passed. */
6102 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6103 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6105 if (ecs
->event_thread
->prev_pc
== stop_pc
6106 && ecs
->event_thread
->control
.trap_expected
6107 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6111 /* We were just starting a new sequence, attempting to
6112 single-step off of a breakpoint and expecting a SIGTRAP.
6113 Instead this signal arrives. This signal will take us out
6114 of the stepping range so GDB needs to remember to, when
6115 the signal handler returns, resume stepping off that
6117 /* To simplify things, "continue" is forced to use the same
6118 code paths as single-step - set a breakpoint at the
6119 signal return address and then, once hit, step off that
6122 fprintf_unfiltered (gdb_stdlog
,
6123 "infrun: signal arrived while stepping over "
6126 was_in_line
= step_over_info_valid_p ();
6127 clear_step_over_info ();
6128 insert_hp_step_resume_breakpoint_at_frame (frame
);
6129 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6130 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6131 ecs
->event_thread
->control
.trap_expected
= 0;
6133 if (target_is_non_stop_p ())
6135 /* Either "set non-stop" is "on", or the target is
6136 always in non-stop mode. In this case, we have a bit
6137 more work to do. Resume the current thread, and if
6138 we had paused all threads, restart them while the
6139 signal handler runs. */
6144 restart_threads (ecs
->event_thread
);
6146 else if (debug_infrun
)
6148 fprintf_unfiltered (gdb_stdlog
,
6149 "infrun: no need to restart threads\n");
6154 /* If we were nexting/stepping some other thread, switch to
6155 it, so that we don't continue it, losing control. */
6156 if (!switch_back_to_stepped_thread (ecs
))
6161 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6162 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6163 || ecs
->event_thread
->control
.step_range_end
== 1)
6164 && frame_id_eq (get_stack_frame_id (frame
),
6165 ecs
->event_thread
->control
.step_stack_frame_id
)
6166 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6168 /* The inferior is about to take a signal that will take it
6169 out of the single step range. Set a breakpoint at the
6170 current PC (which is presumably where the signal handler
6171 will eventually return) and then allow the inferior to
6174 Note that this is only needed for a signal delivered
6175 while in the single-step range. Nested signals aren't a
6176 problem as they eventually all return. */
6178 fprintf_unfiltered (gdb_stdlog
,
6179 "infrun: signal may take us out of "
6180 "single-step range\n");
6182 clear_step_over_info ();
6183 insert_hp_step_resume_breakpoint_at_frame (frame
);
6184 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6185 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6186 ecs
->event_thread
->control
.trap_expected
= 0;
6191 /* Note: step_resume_breakpoint may be non-NULL. This occures
6192 when either there's a nested signal, or when there's a
6193 pending signal enabled just as the signal handler returns
6194 (leaving the inferior at the step-resume-breakpoint without
6195 actually executing it). Either way continue until the
6196 breakpoint is really hit. */
6198 if (!switch_back_to_stepped_thread (ecs
))
6201 fprintf_unfiltered (gdb_stdlog
,
6202 "infrun: random signal, keep going\n");
6209 process_event_stop_test (ecs
);
6212 /* Come here when we've got some debug event / signal we can explain
6213 (IOW, not a random signal), and test whether it should cause a
6214 stop, or whether we should resume the inferior (transparently).
6215 E.g., could be a breakpoint whose condition evaluates false; we
6216 could be still stepping within the line; etc. */
6219 process_event_stop_test (struct execution_control_state
*ecs
)
6221 struct symtab_and_line stop_pc_sal
;
6222 struct frame_info
*frame
;
6223 struct gdbarch
*gdbarch
;
6224 CORE_ADDR jmp_buf_pc
;
6225 struct bpstat_what what
;
6227 /* Handle cases caused by hitting a breakpoint. */
6229 frame
= get_current_frame ();
6230 gdbarch
= get_frame_arch (frame
);
6232 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6234 if (what
.call_dummy
)
6236 stop_stack_dummy
= what
.call_dummy
;
6239 /* A few breakpoint types have callbacks associated (e.g.,
6240 bp_jit_event). Run them now. */
6241 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6243 /* If we hit an internal event that triggers symbol changes, the
6244 current frame will be invalidated within bpstat_what (e.g., if we
6245 hit an internal solib event). Re-fetch it. */
6246 frame
= get_current_frame ();
6247 gdbarch
= get_frame_arch (frame
);
6249 switch (what
.main_action
)
6251 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6252 /* If we hit the breakpoint at longjmp while stepping, we
6253 install a momentary breakpoint at the target of the
6257 fprintf_unfiltered (gdb_stdlog
,
6258 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6260 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6262 if (what
.is_longjmp
)
6264 struct value
*arg_value
;
6266 /* If we set the longjmp breakpoint via a SystemTap probe,
6267 then use it to extract the arguments. The destination PC
6268 is the third argument to the probe. */
6269 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6272 jmp_buf_pc
= value_as_address (arg_value
);
6273 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6275 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6276 || !gdbarch_get_longjmp_target (gdbarch
,
6277 frame
, &jmp_buf_pc
))
6280 fprintf_unfiltered (gdb_stdlog
,
6281 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6282 "(!gdbarch_get_longjmp_target)\n");
6287 /* Insert a breakpoint at resume address. */
6288 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6291 check_exception_resume (ecs
, frame
);
6295 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6297 struct frame_info
*init_frame
;
6299 /* There are several cases to consider.
6301 1. The initiating frame no longer exists. In this case we
6302 must stop, because the exception or longjmp has gone too
6305 2. The initiating frame exists, and is the same as the
6306 current frame. We stop, because the exception or longjmp
6309 3. The initiating frame exists and is different from the
6310 current frame. This means the exception or longjmp has
6311 been caught beneath the initiating frame, so keep going.
6313 4. longjmp breakpoint has been placed just to protect
6314 against stale dummy frames and user is not interested in
6315 stopping around longjmps. */
6318 fprintf_unfiltered (gdb_stdlog
,
6319 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6321 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6323 delete_exception_resume_breakpoint (ecs
->event_thread
);
6325 if (what
.is_longjmp
)
6327 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6329 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6337 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6341 struct frame_id current_id
6342 = get_frame_id (get_current_frame ());
6343 if (frame_id_eq (current_id
,
6344 ecs
->event_thread
->initiating_frame
))
6346 /* Case 2. Fall through. */
6356 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6358 delete_step_resume_breakpoint (ecs
->event_thread
);
6360 end_stepping_range (ecs
);
6364 case BPSTAT_WHAT_SINGLE
:
6366 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6367 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6368 /* Still need to check other stuff, at least the case where we
6369 are stepping and step out of the right range. */
6372 case BPSTAT_WHAT_STEP_RESUME
:
6374 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6376 delete_step_resume_breakpoint (ecs
->event_thread
);
6377 if (ecs
->event_thread
->control
.proceed_to_finish
6378 && execution_direction
== EXEC_REVERSE
)
6380 struct thread_info
*tp
= ecs
->event_thread
;
6382 /* We are finishing a function in reverse, and just hit the
6383 step-resume breakpoint at the start address of the
6384 function, and we're almost there -- just need to back up
6385 by one more single-step, which should take us back to the
6387 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6391 fill_in_stop_func (gdbarch
, ecs
);
6392 if (stop_pc
== ecs
->stop_func_start
6393 && execution_direction
== EXEC_REVERSE
)
6395 /* We are stepping over a function call in reverse, and just
6396 hit the step-resume breakpoint at the start address of
6397 the function. Go back to single-stepping, which should
6398 take us back to the function call. */
6399 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6405 case BPSTAT_WHAT_STOP_NOISY
:
6407 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6408 stop_print_frame
= 1;
6410 /* Assume the thread stopped for a breapoint. We'll still check
6411 whether a/the breakpoint is there when the thread is next
6413 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6418 case BPSTAT_WHAT_STOP_SILENT
:
6420 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6421 stop_print_frame
= 0;
6423 /* Assume the thread stopped for a breapoint. We'll still check
6424 whether a/the breakpoint is there when the thread is next
6426 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6430 case BPSTAT_WHAT_HP_STEP_RESUME
:
6432 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6434 delete_step_resume_breakpoint (ecs
->event_thread
);
6435 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6437 /* Back when the step-resume breakpoint was inserted, we
6438 were trying to single-step off a breakpoint. Go back to
6440 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6441 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6447 case BPSTAT_WHAT_KEEP_CHECKING
:
6451 /* If we stepped a permanent breakpoint and we had a high priority
6452 step-resume breakpoint for the address we stepped, but we didn't
6453 hit it, then we must have stepped into the signal handler. The
6454 step-resume was only necessary to catch the case of _not_
6455 stepping into the handler, so delete it, and fall through to
6456 checking whether the step finished. */
6457 if (ecs
->event_thread
->stepped_breakpoint
)
6459 struct breakpoint
*sr_bp
6460 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6463 && sr_bp
->loc
->permanent
6464 && sr_bp
->type
== bp_hp_step_resume
6465 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6468 fprintf_unfiltered (gdb_stdlog
,
6469 "infrun: stepped permanent breakpoint, stopped in "
6471 delete_step_resume_breakpoint (ecs
->event_thread
);
6472 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6476 /* We come here if we hit a breakpoint but should not stop for it.
6477 Possibly we also were stepping and should stop for that. So fall
6478 through and test for stepping. But, if not stepping, do not
6481 /* In all-stop mode, if we're currently stepping but have stopped in
6482 some other thread, we need to switch back to the stepped thread. */
6483 if (switch_back_to_stepped_thread (ecs
))
6486 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6489 fprintf_unfiltered (gdb_stdlog
,
6490 "infrun: step-resume breakpoint is inserted\n");
6492 /* Having a step-resume breakpoint overrides anything
6493 else having to do with stepping commands until
6494 that breakpoint is reached. */
6499 if (ecs
->event_thread
->control
.step_range_end
== 0)
6502 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6503 /* Likewise if we aren't even stepping. */
6508 /* Re-fetch current thread's frame in case the code above caused
6509 the frame cache to be re-initialized, making our FRAME variable
6510 a dangling pointer. */
6511 frame
= get_current_frame ();
6512 gdbarch
= get_frame_arch (frame
);
6513 fill_in_stop_func (gdbarch
, ecs
);
6515 /* If stepping through a line, keep going if still within it.
6517 Note that step_range_end is the address of the first instruction
6518 beyond the step range, and NOT the address of the last instruction
6521 Note also that during reverse execution, we may be stepping
6522 through a function epilogue and therefore must detect when
6523 the current-frame changes in the middle of a line. */
6525 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6526 && (execution_direction
!= EXEC_REVERSE
6527 || frame_id_eq (get_frame_id (frame
),
6528 ecs
->event_thread
->control
.step_frame_id
)))
6532 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6533 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6534 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6536 /* Tentatively re-enable range stepping; `resume' disables it if
6537 necessary (e.g., if we're stepping over a breakpoint or we
6538 have software watchpoints). */
6539 ecs
->event_thread
->control
.may_range_step
= 1;
6541 /* When stepping backward, stop at beginning of line range
6542 (unless it's the function entry point, in which case
6543 keep going back to the call point). */
6544 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6545 && stop_pc
!= ecs
->stop_func_start
6546 && execution_direction
== EXEC_REVERSE
)
6547 end_stepping_range (ecs
);
6554 /* We stepped out of the stepping range. */
6556 /* If we are stepping at the source level and entered the runtime
6557 loader dynamic symbol resolution code...
6559 EXEC_FORWARD: we keep on single stepping until we exit the run
6560 time loader code and reach the callee's address.
6562 EXEC_REVERSE: we've already executed the callee (backward), and
6563 the runtime loader code is handled just like any other
6564 undebuggable function call. Now we need only keep stepping
6565 backward through the trampoline code, and that's handled further
6566 down, so there is nothing for us to do here. */
6568 if (execution_direction
!= EXEC_REVERSE
6569 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6570 && in_solib_dynsym_resolve_code (stop_pc
))
6572 CORE_ADDR pc_after_resolver
=
6573 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6576 fprintf_unfiltered (gdb_stdlog
,
6577 "infrun: stepped into dynsym resolve code\n");
6579 if (pc_after_resolver
)
6581 /* Set up a step-resume breakpoint at the address
6582 indicated by SKIP_SOLIB_RESOLVER. */
6583 struct symtab_and_line sr_sal
;
6586 sr_sal
.pc
= pc_after_resolver
;
6587 sr_sal
.pspace
= get_frame_program_space (frame
);
6589 insert_step_resume_breakpoint_at_sal (gdbarch
,
6590 sr_sal
, null_frame_id
);
6597 if (ecs
->event_thread
->control
.step_range_end
!= 1
6598 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6599 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6600 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6603 fprintf_unfiltered (gdb_stdlog
,
6604 "infrun: stepped into signal trampoline\n");
6605 /* The inferior, while doing a "step" or "next", has ended up in
6606 a signal trampoline (either by a signal being delivered or by
6607 the signal handler returning). Just single-step until the
6608 inferior leaves the trampoline (either by calling the handler
6614 /* If we're in the return path from a shared library trampoline,
6615 we want to proceed through the trampoline when stepping. */
6616 /* macro/2012-04-25: This needs to come before the subroutine
6617 call check below as on some targets return trampolines look
6618 like subroutine calls (MIPS16 return thunks). */
6619 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6620 stop_pc
, ecs
->stop_func_name
)
6621 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6623 /* Determine where this trampoline returns. */
6624 CORE_ADDR real_stop_pc
;
6626 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6629 fprintf_unfiltered (gdb_stdlog
,
6630 "infrun: stepped into solib return tramp\n");
6632 /* Only proceed through if we know where it's going. */
6635 /* And put the step-breakpoint there and go until there. */
6636 struct symtab_and_line sr_sal
;
6638 init_sal (&sr_sal
); /* initialize to zeroes */
6639 sr_sal
.pc
= real_stop_pc
;
6640 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6641 sr_sal
.pspace
= get_frame_program_space (frame
);
6643 /* Do not specify what the fp should be when we stop since
6644 on some machines the prologue is where the new fp value
6646 insert_step_resume_breakpoint_at_sal (gdbarch
,
6647 sr_sal
, null_frame_id
);
6649 /* Restart without fiddling with the step ranges or
6656 /* Check for subroutine calls. The check for the current frame
6657 equalling the step ID is not necessary - the check of the
6658 previous frame's ID is sufficient - but it is a common case and
6659 cheaper than checking the previous frame's ID.
6661 NOTE: frame_id_eq will never report two invalid frame IDs as
6662 being equal, so to get into this block, both the current and
6663 previous frame must have valid frame IDs. */
6664 /* The outer_frame_id check is a heuristic to detect stepping
6665 through startup code. If we step over an instruction which
6666 sets the stack pointer from an invalid value to a valid value,
6667 we may detect that as a subroutine call from the mythical
6668 "outermost" function. This could be fixed by marking
6669 outermost frames as !stack_p,code_p,special_p. Then the
6670 initial outermost frame, before sp was valid, would
6671 have code_addr == &_start. See the comment in frame_id_eq
6673 if (!frame_id_eq (get_stack_frame_id (frame
),
6674 ecs
->event_thread
->control
.step_stack_frame_id
)
6675 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6676 ecs
->event_thread
->control
.step_stack_frame_id
)
6677 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6679 || (ecs
->event_thread
->control
.step_start_function
6680 != find_pc_function (stop_pc
)))))
6682 CORE_ADDR real_stop_pc
;
6685 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6687 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6689 /* I presume that step_over_calls is only 0 when we're
6690 supposed to be stepping at the assembly language level
6691 ("stepi"). Just stop. */
6692 /* And this works the same backward as frontward. MVS */
6693 end_stepping_range (ecs
);
6697 /* Reverse stepping through solib trampolines. */
6699 if (execution_direction
== EXEC_REVERSE
6700 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6701 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6702 || (ecs
->stop_func_start
== 0
6703 && in_solib_dynsym_resolve_code (stop_pc
))))
6705 /* Any solib trampoline code can be handled in reverse
6706 by simply continuing to single-step. We have already
6707 executed the solib function (backwards), and a few
6708 steps will take us back through the trampoline to the
6714 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6716 /* We're doing a "next".
6718 Normal (forward) execution: set a breakpoint at the
6719 callee's return address (the address at which the caller
6722 Reverse (backward) execution. set the step-resume
6723 breakpoint at the start of the function that we just
6724 stepped into (backwards), and continue to there. When we
6725 get there, we'll need to single-step back to the caller. */
6727 if (execution_direction
== EXEC_REVERSE
)
6729 /* If we're already at the start of the function, we've either
6730 just stepped backward into a single instruction function,
6731 or stepped back out of a signal handler to the first instruction
6732 of the function. Just keep going, which will single-step back
6734 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6736 struct symtab_and_line sr_sal
;
6738 /* Normal function call return (static or dynamic). */
6740 sr_sal
.pc
= ecs
->stop_func_start
;
6741 sr_sal
.pspace
= get_frame_program_space (frame
);
6742 insert_step_resume_breakpoint_at_sal (gdbarch
,
6743 sr_sal
, null_frame_id
);
6747 insert_step_resume_breakpoint_at_caller (frame
);
6753 /* If we are in a function call trampoline (a stub between the
6754 calling routine and the real function), locate the real
6755 function. That's what tells us (a) whether we want to step
6756 into it at all, and (b) what prologue we want to run to the
6757 end of, if we do step into it. */
6758 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6759 if (real_stop_pc
== 0)
6760 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6761 if (real_stop_pc
!= 0)
6762 ecs
->stop_func_start
= real_stop_pc
;
6764 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6766 struct symtab_and_line sr_sal
;
6769 sr_sal
.pc
= ecs
->stop_func_start
;
6770 sr_sal
.pspace
= get_frame_program_space (frame
);
6772 insert_step_resume_breakpoint_at_sal (gdbarch
,
6773 sr_sal
, null_frame_id
);
6778 /* If we have line number information for the function we are
6779 thinking of stepping into and the function isn't on the skip
6782 If there are several symtabs at that PC (e.g. with include
6783 files), just want to know whether *any* of them have line
6784 numbers. find_pc_line handles this. */
6786 struct symtab_and_line tmp_sal
;
6788 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6789 if (tmp_sal
.line
!= 0
6790 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6793 if (execution_direction
== EXEC_REVERSE
)
6794 handle_step_into_function_backward (gdbarch
, ecs
);
6796 handle_step_into_function (gdbarch
, ecs
);
6801 /* If we have no line number and the step-stop-if-no-debug is
6802 set, we stop the step so that the user has a chance to switch
6803 in assembly mode. */
6804 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6805 && step_stop_if_no_debug
)
6807 end_stepping_range (ecs
);
6811 if (execution_direction
== EXEC_REVERSE
)
6813 /* If we're already at the start of the function, we've either just
6814 stepped backward into a single instruction function without line
6815 number info, or stepped back out of a signal handler to the first
6816 instruction of the function without line number info. Just keep
6817 going, which will single-step back to the caller. */
6818 if (ecs
->stop_func_start
!= stop_pc
)
6820 /* Set a breakpoint at callee's start address.
6821 From there we can step once and be back in the caller. */
6822 struct symtab_and_line sr_sal
;
6825 sr_sal
.pc
= ecs
->stop_func_start
;
6826 sr_sal
.pspace
= get_frame_program_space (frame
);
6827 insert_step_resume_breakpoint_at_sal (gdbarch
,
6828 sr_sal
, null_frame_id
);
6832 /* Set a breakpoint at callee's return address (the address
6833 at which the caller will resume). */
6834 insert_step_resume_breakpoint_at_caller (frame
);
6840 /* Reverse stepping through solib trampolines. */
6842 if (execution_direction
== EXEC_REVERSE
6843 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6845 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6846 || (ecs
->stop_func_start
== 0
6847 && in_solib_dynsym_resolve_code (stop_pc
)))
6849 /* Any solib trampoline code can be handled in reverse
6850 by simply continuing to single-step. We have already
6851 executed the solib function (backwards), and a few
6852 steps will take us back through the trampoline to the
6857 else if (in_solib_dynsym_resolve_code (stop_pc
))
6859 /* Stepped backward into the solib dynsym resolver.
6860 Set a breakpoint at its start and continue, then
6861 one more step will take us out. */
6862 struct symtab_and_line sr_sal
;
6865 sr_sal
.pc
= ecs
->stop_func_start
;
6866 sr_sal
.pspace
= get_frame_program_space (frame
);
6867 insert_step_resume_breakpoint_at_sal (gdbarch
,
6868 sr_sal
, null_frame_id
);
6874 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6876 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6877 the trampoline processing logic, however, there are some trampolines
6878 that have no names, so we should do trampoline handling first. */
6879 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6880 && ecs
->stop_func_name
== NULL
6881 && stop_pc_sal
.line
== 0)
6884 fprintf_unfiltered (gdb_stdlog
,
6885 "infrun: stepped into undebuggable function\n");
6887 /* The inferior just stepped into, or returned to, an
6888 undebuggable function (where there is no debugging information
6889 and no line number corresponding to the address where the
6890 inferior stopped). Since we want to skip this kind of code,
6891 we keep going until the inferior returns from this
6892 function - unless the user has asked us not to (via
6893 set step-mode) or we no longer know how to get back
6894 to the call site. */
6895 if (step_stop_if_no_debug
6896 || !frame_id_p (frame_unwind_caller_id (frame
)))
6898 /* If we have no line number and the step-stop-if-no-debug
6899 is set, we stop the step so that the user has a chance to
6900 switch in assembly mode. */
6901 end_stepping_range (ecs
);
6906 /* Set a breakpoint at callee's return address (the address
6907 at which the caller will resume). */
6908 insert_step_resume_breakpoint_at_caller (frame
);
6914 if (ecs
->event_thread
->control
.step_range_end
== 1)
6916 /* It is stepi or nexti. We always want to stop stepping after
6919 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6920 end_stepping_range (ecs
);
6924 if (stop_pc_sal
.line
== 0)
6926 /* We have no line number information. That means to stop
6927 stepping (does this always happen right after one instruction,
6928 when we do "s" in a function with no line numbers,
6929 or can this happen as a result of a return or longjmp?). */
6931 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6932 end_stepping_range (ecs
);
6936 /* Look for "calls" to inlined functions, part one. If the inline
6937 frame machinery detected some skipped call sites, we have entered
6938 a new inline function. */
6940 if (frame_id_eq (get_frame_id (get_current_frame ()),
6941 ecs
->event_thread
->control
.step_frame_id
)
6942 && inline_skipped_frames (ecs
->ptid
))
6944 struct symtab_and_line call_sal
;
6947 fprintf_unfiltered (gdb_stdlog
,
6948 "infrun: stepped into inlined function\n");
6950 find_frame_sal (get_current_frame (), &call_sal
);
6952 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6954 /* For "step", we're going to stop. But if the call site
6955 for this inlined function is on the same source line as
6956 we were previously stepping, go down into the function
6957 first. Otherwise stop at the call site. */
6959 if (call_sal
.line
== ecs
->event_thread
->current_line
6960 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6961 step_into_inline_frame (ecs
->ptid
);
6963 end_stepping_range (ecs
);
6968 /* For "next", we should stop at the call site if it is on a
6969 different source line. Otherwise continue through the
6970 inlined function. */
6971 if (call_sal
.line
== ecs
->event_thread
->current_line
6972 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6975 end_stepping_range (ecs
);
6980 /* Look for "calls" to inlined functions, part two. If we are still
6981 in the same real function we were stepping through, but we have
6982 to go further up to find the exact frame ID, we are stepping
6983 through a more inlined call beyond its call site. */
6985 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6986 && !frame_id_eq (get_frame_id (get_current_frame ()),
6987 ecs
->event_thread
->control
.step_frame_id
)
6988 && stepped_in_from (get_current_frame (),
6989 ecs
->event_thread
->control
.step_frame_id
))
6992 fprintf_unfiltered (gdb_stdlog
,
6993 "infrun: stepping through inlined function\n");
6995 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6998 end_stepping_range (ecs
);
7002 if ((stop_pc
== stop_pc_sal
.pc
)
7003 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
7004 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
7006 /* We are at the start of a different line. So stop. Note that
7007 we don't stop if we step into the middle of a different line.
7008 That is said to make things like for (;;) statements work
7011 fprintf_unfiltered (gdb_stdlog
,
7012 "infrun: stepped to a different line\n");
7013 end_stepping_range (ecs
);
7017 /* We aren't done stepping.
7019 Optimize by setting the stepping range to the line.
7020 (We might not be in the original line, but if we entered a
7021 new line in mid-statement, we continue stepping. This makes
7022 things like for(;;) statements work better.) */
7024 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7025 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7026 ecs
->event_thread
->control
.may_range_step
= 1;
7027 set_step_info (frame
, stop_pc_sal
);
7030 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
7034 /* In all-stop mode, if we're currently stepping but have stopped in
7035 some other thread, we may need to switch back to the stepped
7036 thread. Returns true we set the inferior running, false if we left
7037 it stopped (and the event needs further processing). */
7040 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7042 if (!target_is_non_stop_p ())
7044 struct thread_info
*tp
;
7045 struct thread_info
*stepping_thread
;
7047 /* If any thread is blocked on some internal breakpoint, and we
7048 simply need to step over that breakpoint to get it going
7049 again, do that first. */
7051 /* However, if we see an event for the stepping thread, then we
7052 know all other threads have been moved past their breakpoints
7053 already. Let the caller check whether the step is finished,
7054 etc., before deciding to move it past a breakpoint. */
7055 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7058 /* Check if the current thread is blocked on an incomplete
7059 step-over, interrupted by a random signal. */
7060 if (ecs
->event_thread
->control
.trap_expected
7061 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7065 fprintf_unfiltered (gdb_stdlog
,
7066 "infrun: need to finish step-over of [%s]\n",
7067 target_pid_to_str (ecs
->event_thread
->ptid
));
7073 /* Check if the current thread is blocked by a single-step
7074 breakpoint of another thread. */
7075 if (ecs
->hit_singlestep_breakpoint
)
7079 fprintf_unfiltered (gdb_stdlog
,
7080 "infrun: need to step [%s] over single-step "
7082 target_pid_to_str (ecs
->ptid
));
7088 /* If this thread needs yet another step-over (e.g., stepping
7089 through a delay slot), do it first before moving on to
7091 if (thread_still_needs_step_over (ecs
->event_thread
))
7095 fprintf_unfiltered (gdb_stdlog
,
7096 "infrun: thread [%s] still needs step-over\n",
7097 target_pid_to_str (ecs
->event_thread
->ptid
));
7103 /* If scheduler locking applies even if not stepping, there's no
7104 need to walk over threads. Above we've checked whether the
7105 current thread is stepping. If some other thread not the
7106 event thread is stepping, then it must be that scheduler
7107 locking is not in effect. */
7108 if (schedlock_applies (ecs
->event_thread
))
7111 /* Otherwise, we no longer expect a trap in the current thread.
7112 Clear the trap_expected flag before switching back -- this is
7113 what keep_going does as well, if we call it. */
7114 ecs
->event_thread
->control
.trap_expected
= 0;
7116 /* Likewise, clear the signal if it should not be passed. */
7117 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7118 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7120 /* Do all pending step-overs before actually proceeding with
7122 if (start_step_over ())
7124 prepare_to_wait (ecs
);
7128 /* Look for the stepping/nexting thread. */
7129 stepping_thread
= NULL
;
7131 ALL_NON_EXITED_THREADS (tp
)
7133 /* Ignore threads of processes the caller is not
7136 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
7139 /* When stepping over a breakpoint, we lock all threads
7140 except the one that needs to move past the breakpoint.
7141 If a non-event thread has this set, the "incomplete
7142 step-over" check above should have caught it earlier. */
7143 if (tp
->control
.trap_expected
)
7145 internal_error (__FILE__
, __LINE__
,
7146 "[%s] has inconsistent state: "
7147 "trap_expected=%d\n",
7148 target_pid_to_str (tp
->ptid
),
7149 tp
->control
.trap_expected
);
7152 /* Did we find the stepping thread? */
7153 if (tp
->control
.step_range_end
)
7155 /* Yep. There should only one though. */
7156 gdb_assert (stepping_thread
== NULL
);
7158 /* The event thread is handled at the top, before we
7160 gdb_assert (tp
!= ecs
->event_thread
);
7162 /* If some thread other than the event thread is
7163 stepping, then scheduler locking can't be in effect,
7164 otherwise we wouldn't have resumed the current event
7165 thread in the first place. */
7166 gdb_assert (!schedlock_applies (tp
));
7168 stepping_thread
= tp
;
7172 if (stepping_thread
!= NULL
)
7175 fprintf_unfiltered (gdb_stdlog
,
7176 "infrun: switching back to stepped thread\n");
7178 if (keep_going_stepped_thread (stepping_thread
))
7180 prepare_to_wait (ecs
);
7189 /* Set a previously stepped thread back to stepping. Returns true on
7190 success, false if the resume is not possible (e.g., the thread
7194 keep_going_stepped_thread (struct thread_info
*tp
)
7196 struct frame_info
*frame
;
7197 struct execution_control_state ecss
;
7198 struct execution_control_state
*ecs
= &ecss
;
7200 /* If the stepping thread exited, then don't try to switch back and
7201 resume it, which could fail in several different ways depending
7202 on the target. Instead, just keep going.
7204 We can find a stepping dead thread in the thread list in two
7207 - The target supports thread exit events, and when the target
7208 tries to delete the thread from the thread list, inferior_ptid
7209 pointed at the exiting thread. In such case, calling
7210 delete_thread does not really remove the thread from the list;
7211 instead, the thread is left listed, with 'exited' state.
7213 - The target's debug interface does not support thread exit
7214 events, and so we have no idea whatsoever if the previously
7215 stepping thread is still alive. For that reason, we need to
7216 synchronously query the target now. */
7218 if (is_exited (tp
->ptid
)
7219 || !target_thread_alive (tp
->ptid
))
7222 fprintf_unfiltered (gdb_stdlog
,
7223 "infrun: not resuming previously "
7224 "stepped thread, it has vanished\n");
7226 delete_thread (tp
->ptid
);
7231 fprintf_unfiltered (gdb_stdlog
,
7232 "infrun: resuming previously stepped thread\n");
7234 reset_ecs (ecs
, tp
);
7235 switch_to_thread (tp
->ptid
);
7237 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
7238 frame
= get_current_frame ();
7240 /* If the PC of the thread we were trying to single-step has
7241 changed, then that thread has trapped or been signaled, but the
7242 event has not been reported to GDB yet. Re-poll the target
7243 looking for this particular thread's event (i.e. temporarily
7244 enable schedlock) by:
7246 - setting a break at the current PC
7247 - resuming that particular thread, only (by setting trap
7250 This prevents us continuously moving the single-step breakpoint
7251 forward, one instruction at a time, overstepping. */
7253 if (stop_pc
!= tp
->prev_pc
)
7258 fprintf_unfiltered (gdb_stdlog
,
7259 "infrun: expected thread advanced also (%s -> %s)\n",
7260 paddress (target_gdbarch (), tp
->prev_pc
),
7261 paddress (target_gdbarch (), stop_pc
));
7263 /* Clear the info of the previous step-over, as it's no longer
7264 valid (if the thread was trying to step over a breakpoint, it
7265 has already succeeded). It's what keep_going would do too,
7266 if we called it. Do this before trying to insert the sss
7267 breakpoint, otherwise if we were previously trying to step
7268 over this exact address in another thread, the breakpoint is
7270 clear_step_over_info ();
7271 tp
->control
.trap_expected
= 0;
7273 insert_single_step_breakpoint (get_frame_arch (frame
),
7274 get_frame_address_space (frame
),
7278 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7279 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7284 fprintf_unfiltered (gdb_stdlog
,
7285 "infrun: expected thread still hasn't advanced\n");
7287 keep_going_pass_signal (ecs
);
7292 /* Is thread TP in the middle of (software or hardware)
7293 single-stepping? (Note the result of this function must never be
7294 passed directly as target_resume's STEP parameter.) */
7297 currently_stepping (struct thread_info
*tp
)
7299 return ((tp
->control
.step_range_end
7300 && tp
->control
.step_resume_breakpoint
== NULL
)
7301 || tp
->control
.trap_expected
7302 || tp
->stepped_breakpoint
7303 || bpstat_should_step ());
7306 /* Inferior has stepped into a subroutine call with source code that
7307 we should not step over. Do step to the first line of code in
7311 handle_step_into_function (struct gdbarch
*gdbarch
,
7312 struct execution_control_state
*ecs
)
7314 struct compunit_symtab
*cust
;
7315 struct symtab_and_line stop_func_sal
, sr_sal
;
7317 fill_in_stop_func (gdbarch
, ecs
);
7319 cust
= find_pc_compunit_symtab (stop_pc
);
7320 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7321 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7322 ecs
->stop_func_start
);
7324 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7325 /* Use the step_resume_break to step until the end of the prologue,
7326 even if that involves jumps (as it seems to on the vax under
7328 /* If the prologue ends in the middle of a source line, continue to
7329 the end of that source line (if it is still within the function).
7330 Otherwise, just go to end of prologue. */
7331 if (stop_func_sal
.end
7332 && stop_func_sal
.pc
!= ecs
->stop_func_start
7333 && stop_func_sal
.end
< ecs
->stop_func_end
)
7334 ecs
->stop_func_start
= stop_func_sal
.end
;
7336 /* Architectures which require breakpoint adjustment might not be able
7337 to place a breakpoint at the computed address. If so, the test
7338 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7339 ecs->stop_func_start to an address at which a breakpoint may be
7340 legitimately placed.
7342 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7343 made, GDB will enter an infinite loop when stepping through
7344 optimized code consisting of VLIW instructions which contain
7345 subinstructions corresponding to different source lines. On
7346 FR-V, it's not permitted to place a breakpoint on any but the
7347 first subinstruction of a VLIW instruction. When a breakpoint is
7348 set, GDB will adjust the breakpoint address to the beginning of
7349 the VLIW instruction. Thus, we need to make the corresponding
7350 adjustment here when computing the stop address. */
7352 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7354 ecs
->stop_func_start
7355 = gdbarch_adjust_breakpoint_address (gdbarch
,
7356 ecs
->stop_func_start
);
7359 if (ecs
->stop_func_start
== stop_pc
)
7361 /* We are already there: stop now. */
7362 end_stepping_range (ecs
);
7367 /* Put the step-breakpoint there and go until there. */
7368 init_sal (&sr_sal
); /* initialize to zeroes */
7369 sr_sal
.pc
= ecs
->stop_func_start
;
7370 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7371 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7373 /* Do not specify what the fp should be when we stop since on
7374 some machines the prologue is where the new fp value is
7376 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7378 /* And make sure stepping stops right away then. */
7379 ecs
->event_thread
->control
.step_range_end
7380 = ecs
->event_thread
->control
.step_range_start
;
7385 /* Inferior has stepped backward into a subroutine call with source
7386 code that we should not step over. Do step to the beginning of the
7387 last line of code in it. */
7390 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7391 struct execution_control_state
*ecs
)
7393 struct compunit_symtab
*cust
;
7394 struct symtab_and_line stop_func_sal
;
7396 fill_in_stop_func (gdbarch
, ecs
);
7398 cust
= find_pc_compunit_symtab (stop_pc
);
7399 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7400 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7401 ecs
->stop_func_start
);
7403 stop_func_sal
= find_pc_line (stop_pc
, 0);
7405 /* OK, we're just going to keep stepping here. */
7406 if (stop_func_sal
.pc
== stop_pc
)
7408 /* We're there already. Just stop stepping now. */
7409 end_stepping_range (ecs
);
7413 /* Else just reset the step range and keep going.
7414 No step-resume breakpoint, they don't work for
7415 epilogues, which can have multiple entry paths. */
7416 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7417 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7423 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7424 This is used to both functions and to skip over code. */
7427 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7428 struct symtab_and_line sr_sal
,
7429 struct frame_id sr_id
,
7430 enum bptype sr_type
)
7432 /* There should never be more than one step-resume or longjmp-resume
7433 breakpoint per thread, so we should never be setting a new
7434 step_resume_breakpoint when one is already active. */
7435 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7436 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7439 fprintf_unfiltered (gdb_stdlog
,
7440 "infrun: inserting step-resume breakpoint at %s\n",
7441 paddress (gdbarch
, sr_sal
.pc
));
7443 inferior_thread ()->control
.step_resume_breakpoint
7444 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
7448 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7449 struct symtab_and_line sr_sal
,
7450 struct frame_id sr_id
)
7452 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7457 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7458 This is used to skip a potential signal handler.
7460 This is called with the interrupted function's frame. The signal
7461 handler, when it returns, will resume the interrupted function at
7465 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7467 struct symtab_and_line sr_sal
;
7468 struct gdbarch
*gdbarch
;
7470 gdb_assert (return_frame
!= NULL
);
7471 init_sal (&sr_sal
); /* initialize to zeros */
7473 gdbarch
= get_frame_arch (return_frame
);
7474 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7475 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7476 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7478 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7479 get_stack_frame_id (return_frame
),
7483 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7484 is used to skip a function after stepping into it (for "next" or if
7485 the called function has no debugging information).
7487 The current function has almost always been reached by single
7488 stepping a call or return instruction. NEXT_FRAME belongs to the
7489 current function, and the breakpoint will be set at the caller's
7492 This is a separate function rather than reusing
7493 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7494 get_prev_frame, which may stop prematurely (see the implementation
7495 of frame_unwind_caller_id for an example). */
7498 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7500 struct symtab_and_line sr_sal
;
7501 struct gdbarch
*gdbarch
;
7503 /* We shouldn't have gotten here if we don't know where the call site
7505 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7507 init_sal (&sr_sal
); /* initialize to zeros */
7509 gdbarch
= frame_unwind_caller_arch (next_frame
);
7510 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7511 frame_unwind_caller_pc (next_frame
));
7512 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7513 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7515 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7516 frame_unwind_caller_id (next_frame
));
7519 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7520 new breakpoint at the target of a jmp_buf. The handling of
7521 longjmp-resume uses the same mechanisms used for handling
7522 "step-resume" breakpoints. */
7525 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7527 /* There should never be more than one longjmp-resume breakpoint per
7528 thread, so we should never be setting a new
7529 longjmp_resume_breakpoint when one is already active. */
7530 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7533 fprintf_unfiltered (gdb_stdlog
,
7534 "infrun: inserting longjmp-resume breakpoint at %s\n",
7535 paddress (gdbarch
, pc
));
7537 inferior_thread ()->control
.exception_resume_breakpoint
=
7538 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
7541 /* Insert an exception resume breakpoint. TP is the thread throwing
7542 the exception. The block B is the block of the unwinder debug hook
7543 function. FRAME is the frame corresponding to the call to this
7544 function. SYM is the symbol of the function argument holding the
7545 target PC of the exception. */
7548 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7549 const struct block
*b
,
7550 struct frame_info
*frame
,
7555 struct block_symbol vsym
;
7556 struct value
*value
;
7558 struct breakpoint
*bp
;
7560 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
7561 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7562 /* If the value was optimized out, revert to the old behavior. */
7563 if (! value_optimized_out (value
))
7565 handler
= value_as_address (value
);
7568 fprintf_unfiltered (gdb_stdlog
,
7569 "infrun: exception resume at %lx\n",
7570 (unsigned long) handler
);
7572 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7573 handler
, bp_exception_resume
);
7575 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7578 bp
->thread
= tp
->global_num
;
7579 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7582 CATCH (e
, RETURN_MASK_ERROR
)
7584 /* We want to ignore errors here. */
7589 /* A helper for check_exception_resume that sets an
7590 exception-breakpoint based on a SystemTap probe. */
7593 insert_exception_resume_from_probe (struct thread_info
*tp
,
7594 const struct bound_probe
*probe
,
7595 struct frame_info
*frame
)
7597 struct value
*arg_value
;
7599 struct breakpoint
*bp
;
7601 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7605 handler
= value_as_address (arg_value
);
7608 fprintf_unfiltered (gdb_stdlog
,
7609 "infrun: exception resume at %s\n",
7610 paddress (get_objfile_arch (probe
->objfile
),
7613 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7614 handler
, bp_exception_resume
);
7615 bp
->thread
= tp
->global_num
;
7616 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7619 /* This is called when an exception has been intercepted. Check to
7620 see whether the exception's destination is of interest, and if so,
7621 set an exception resume breakpoint there. */
7624 check_exception_resume (struct execution_control_state
*ecs
,
7625 struct frame_info
*frame
)
7627 struct bound_probe probe
;
7628 struct symbol
*func
;
7630 /* First see if this exception unwinding breakpoint was set via a
7631 SystemTap probe point. If so, the probe has two arguments: the
7632 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7633 set a breakpoint there. */
7634 probe
= find_probe_by_pc (get_frame_pc (frame
));
7637 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7641 func
= get_frame_function (frame
);
7647 const struct block
*b
;
7648 struct block_iterator iter
;
7652 /* The exception breakpoint is a thread-specific breakpoint on
7653 the unwinder's debug hook, declared as:
7655 void _Unwind_DebugHook (void *cfa, void *handler);
7657 The CFA argument indicates the frame to which control is
7658 about to be transferred. HANDLER is the destination PC.
7660 We ignore the CFA and set a temporary breakpoint at HANDLER.
7661 This is not extremely efficient but it avoids issues in gdb
7662 with computing the DWARF CFA, and it also works even in weird
7663 cases such as throwing an exception from inside a signal
7666 b
= SYMBOL_BLOCK_VALUE (func
);
7667 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7669 if (!SYMBOL_IS_ARGUMENT (sym
))
7676 insert_exception_resume_breakpoint (ecs
->event_thread
,
7682 CATCH (e
, RETURN_MASK_ERROR
)
7689 stop_waiting (struct execution_control_state
*ecs
)
7692 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7694 clear_step_over_info ();
7696 /* Let callers know we don't want to wait for the inferior anymore. */
7697 ecs
->wait_some_more
= 0;
7699 /* If all-stop, but the target is always in non-stop mode, stop all
7700 threads now that we're presenting the stop to the user. */
7701 if (!non_stop
&& target_is_non_stop_p ())
7702 stop_all_threads ();
7705 /* Like keep_going, but passes the signal to the inferior, even if the
7706 signal is set to nopass. */
7709 keep_going_pass_signal (struct execution_control_state
*ecs
)
7711 /* Make sure normal_stop is called if we get a QUIT handled before
7713 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
7715 gdb_assert (ptid_equal (ecs
->event_thread
->ptid
, inferior_ptid
));
7716 gdb_assert (!ecs
->event_thread
->resumed
);
7718 /* Save the pc before execution, to compare with pc after stop. */
7719 ecs
->event_thread
->prev_pc
7720 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
7722 if (ecs
->event_thread
->control
.trap_expected
)
7724 struct thread_info
*tp
= ecs
->event_thread
;
7727 fprintf_unfiltered (gdb_stdlog
,
7728 "infrun: %s has trap_expected set, "
7729 "resuming to collect trap\n",
7730 target_pid_to_str (tp
->ptid
));
7732 /* We haven't yet gotten our trap, and either: intercepted a
7733 non-signal event (e.g., a fork); or took a signal which we
7734 are supposed to pass through to the inferior. Simply
7736 discard_cleanups (old_cleanups
);
7737 resume (ecs
->event_thread
->suspend
.stop_signal
);
7739 else if (step_over_info_valid_p ())
7741 /* Another thread is stepping over a breakpoint in-line. If
7742 this thread needs a step-over too, queue the request. In
7743 either case, this resume must be deferred for later. */
7744 struct thread_info
*tp
= ecs
->event_thread
;
7746 if (ecs
->hit_singlestep_breakpoint
7747 || thread_still_needs_step_over (tp
))
7750 fprintf_unfiltered (gdb_stdlog
,
7751 "infrun: step-over already in progress: "
7752 "step-over for %s deferred\n",
7753 target_pid_to_str (tp
->ptid
));
7754 thread_step_over_chain_enqueue (tp
);
7759 fprintf_unfiltered (gdb_stdlog
,
7760 "infrun: step-over in progress: "
7761 "resume of %s deferred\n",
7762 target_pid_to_str (tp
->ptid
));
7765 discard_cleanups (old_cleanups
);
7769 struct regcache
*regcache
= get_current_regcache ();
7772 step_over_what step_what
;
7774 /* Either the trap was not expected, but we are continuing
7775 anyway (if we got a signal, the user asked it be passed to
7778 We got our expected trap, but decided we should resume from
7781 We're going to run this baby now!
7783 Note that insert_breakpoints won't try to re-insert
7784 already inserted breakpoints. Therefore, we don't
7785 care if breakpoints were already inserted, or not. */
7787 /* If we need to step over a breakpoint, and we're not using
7788 displaced stepping to do so, insert all breakpoints
7789 (watchpoints, etc.) but the one we're stepping over, step one
7790 instruction, and then re-insert the breakpoint when that step
7793 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7795 remove_bp
= (ecs
->hit_singlestep_breakpoint
7796 || (step_what
& STEP_OVER_BREAKPOINT
));
7797 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7799 /* We can't use displaced stepping if we need to step past a
7800 watchpoint. The instruction copied to the scratch pad would
7801 still trigger the watchpoint. */
7803 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7805 set_step_over_info (get_regcache_aspace (regcache
),
7806 regcache_read_pc (regcache
), remove_wps
,
7807 ecs
->event_thread
->global_num
);
7809 else if (remove_wps
)
7810 set_step_over_info (NULL
, 0, remove_wps
, -1);
7812 /* If we now need to do an in-line step-over, we need to stop
7813 all other threads. Note this must be done before
7814 insert_breakpoints below, because that removes the breakpoint
7815 we're about to step over, otherwise other threads could miss
7817 if (step_over_info_valid_p () && target_is_non_stop_p ())
7818 stop_all_threads ();
7820 /* Stop stepping if inserting breakpoints fails. */
7823 insert_breakpoints ();
7825 CATCH (e
, RETURN_MASK_ERROR
)
7827 exception_print (gdb_stderr
, e
);
7829 discard_cleanups (old_cleanups
);
7834 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7836 discard_cleanups (old_cleanups
);
7837 resume (ecs
->event_thread
->suspend
.stop_signal
);
7840 prepare_to_wait (ecs
);
7843 /* Called when we should continue running the inferior, because the
7844 current event doesn't cause a user visible stop. This does the
7845 resuming part; waiting for the next event is done elsewhere. */
7848 keep_going (struct execution_control_state
*ecs
)
7850 if (ecs
->event_thread
->control
.trap_expected
7851 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7852 ecs
->event_thread
->control
.trap_expected
= 0;
7854 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7855 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7856 keep_going_pass_signal (ecs
);
7859 /* This function normally comes after a resume, before
7860 handle_inferior_event exits. It takes care of any last bits of
7861 housekeeping, and sets the all-important wait_some_more flag. */
7864 prepare_to_wait (struct execution_control_state
*ecs
)
7867 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7869 ecs
->wait_some_more
= 1;
7871 if (!target_is_async_p ())
7872 mark_infrun_async_event_handler ();
7875 /* We are done with the step range of a step/next/si/ni command.
7876 Called once for each n of a "step n" operation. */
7879 end_stepping_range (struct execution_control_state
*ecs
)
7881 ecs
->event_thread
->control
.stop_step
= 1;
7885 /* Several print_*_reason functions to print why the inferior has stopped.
7886 We always print something when the inferior exits, or receives a signal.
7887 The rest of the cases are dealt with later on in normal_stop and
7888 print_it_typical. Ideally there should be a call to one of these
7889 print_*_reason functions functions from handle_inferior_event each time
7890 stop_waiting is called.
7892 Note that we don't call these directly, instead we delegate that to
7893 the interpreters, through observers. Interpreters then call these
7894 with whatever uiout is right. */
7897 print_end_stepping_range_reason (struct ui_out
*uiout
)
7899 /* For CLI-like interpreters, print nothing. */
7901 if (ui_out_is_mi_like_p (uiout
))
7903 ui_out_field_string (uiout
, "reason",
7904 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7909 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7911 annotate_signalled ();
7912 if (ui_out_is_mi_like_p (uiout
))
7914 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7915 ui_out_text (uiout
, "\nProgram terminated with signal ");
7916 annotate_signal_name ();
7917 ui_out_field_string (uiout
, "signal-name",
7918 gdb_signal_to_name (siggnal
));
7919 annotate_signal_name_end ();
7920 ui_out_text (uiout
, ", ");
7921 annotate_signal_string ();
7922 ui_out_field_string (uiout
, "signal-meaning",
7923 gdb_signal_to_string (siggnal
));
7924 annotate_signal_string_end ();
7925 ui_out_text (uiout
, ".\n");
7926 ui_out_text (uiout
, "The program no longer exists.\n");
7930 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7932 struct inferior
*inf
= current_inferior ();
7933 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
7935 annotate_exited (exitstatus
);
7938 if (ui_out_is_mi_like_p (uiout
))
7939 ui_out_field_string (uiout
, "reason",
7940 async_reason_lookup (EXEC_ASYNC_EXITED
));
7941 ui_out_text (uiout
, "[Inferior ");
7942 ui_out_text (uiout
, plongest (inf
->num
));
7943 ui_out_text (uiout
, " (");
7944 ui_out_text (uiout
, pidstr
);
7945 ui_out_text (uiout
, ") exited with code ");
7946 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
7947 ui_out_text (uiout
, "]\n");
7951 if (ui_out_is_mi_like_p (uiout
))
7953 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7954 ui_out_text (uiout
, "[Inferior ");
7955 ui_out_text (uiout
, plongest (inf
->num
));
7956 ui_out_text (uiout
, " (");
7957 ui_out_text (uiout
, pidstr
);
7958 ui_out_text (uiout
, ") exited normally]\n");
7962 /* Some targets/architectures can do extra processing/display of
7963 segmentation faults. E.g., Intel MPX boundary faults.
7964 Call the architecture dependent function to handle the fault. */
7967 handle_segmentation_fault (struct ui_out
*uiout
)
7969 struct regcache
*regcache
= get_current_regcache ();
7970 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7972 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7973 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7977 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7979 struct thread_info
*thr
= inferior_thread ();
7983 if (ui_out_is_mi_like_p (uiout
))
7985 else if (show_thread_that_caused_stop ())
7989 ui_out_text (uiout
, "\nThread ");
7990 ui_out_field_fmt (uiout
, "thread-id", "%s", print_thread_id (thr
));
7992 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7995 ui_out_text (uiout
, " \"");
7996 ui_out_field_fmt (uiout
, "name", "%s", name
);
7997 ui_out_text (uiout
, "\"");
8001 ui_out_text (uiout
, "\nProgram");
8003 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
8004 ui_out_text (uiout
, " stopped");
8007 ui_out_text (uiout
, " received signal ");
8008 annotate_signal_name ();
8009 if (ui_out_is_mi_like_p (uiout
))
8011 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
8012 ui_out_field_string (uiout
, "signal-name",
8013 gdb_signal_to_name (siggnal
));
8014 annotate_signal_name_end ();
8015 ui_out_text (uiout
, ", ");
8016 annotate_signal_string ();
8017 ui_out_field_string (uiout
, "signal-meaning",
8018 gdb_signal_to_string (siggnal
));
8020 if (siggnal
== GDB_SIGNAL_SEGV
)
8021 handle_segmentation_fault (uiout
);
8023 annotate_signal_string_end ();
8025 ui_out_text (uiout
, ".\n");
8029 print_no_history_reason (struct ui_out
*uiout
)
8031 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
8034 /* Print current location without a level number, if we have changed
8035 functions or hit a breakpoint. Print source line if we have one.
8036 bpstat_print contains the logic deciding in detail what to print,
8037 based on the event(s) that just occurred. */
8040 print_stop_location (struct target_waitstatus
*ws
)
8043 enum print_what source_flag
;
8044 int do_frame_printing
= 1;
8045 struct thread_info
*tp
= inferior_thread ();
8047 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8051 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8052 should) carry around the function and does (or should) use
8053 that when doing a frame comparison. */
8054 if (tp
->control
.stop_step
8055 && frame_id_eq (tp
->control
.step_frame_id
,
8056 get_frame_id (get_current_frame ()))
8057 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
8059 /* Finished step, just print source line. */
8060 source_flag
= SRC_LINE
;
8064 /* Print location and source line. */
8065 source_flag
= SRC_AND_LOC
;
8068 case PRINT_SRC_AND_LOC
:
8069 /* Print location and source line. */
8070 source_flag
= SRC_AND_LOC
;
8072 case PRINT_SRC_ONLY
:
8073 source_flag
= SRC_LINE
;
8076 /* Something bogus. */
8077 source_flag
= SRC_LINE
;
8078 do_frame_printing
= 0;
8081 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8084 /* The behavior of this routine with respect to the source
8086 SRC_LINE: Print only source line
8087 LOCATION: Print only location
8088 SRC_AND_LOC: Print location and source line. */
8089 if (do_frame_printing
)
8090 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8093 /* Cleanup that restores a previous current uiout. */
8096 restore_current_uiout_cleanup (void *arg
)
8098 struct ui_out
*saved_uiout
= (struct ui_out
*) arg
;
8100 current_uiout
= saved_uiout
;
8106 print_stop_event (struct ui_out
*uiout
)
8108 struct cleanup
*old_chain
;
8109 struct target_waitstatus last
;
8111 struct thread_info
*tp
;
8113 get_last_target_status (&last_ptid
, &last
);
8115 old_chain
= make_cleanup (restore_current_uiout_cleanup
, current_uiout
);
8116 current_uiout
= uiout
;
8118 print_stop_location (&last
);
8120 /* Display the auto-display expressions. */
8123 do_cleanups (old_chain
);
8125 tp
= inferior_thread ();
8126 if (tp
->thread_fsm
!= NULL
8127 && thread_fsm_finished_p (tp
->thread_fsm
))
8129 struct return_value_info
*rv
;
8131 rv
= thread_fsm_return_value (tp
->thread_fsm
);
8133 print_return_value (uiout
, rv
);
8140 maybe_remove_breakpoints (void)
8142 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
8144 if (remove_breakpoints ())
8146 target_terminal_ours_for_output ();
8147 printf_filtered (_("Cannot remove breakpoints because "
8148 "program is no longer writable.\nFurther "
8149 "execution is probably impossible.\n"));
8154 /* The execution context that just caused a normal stop. */
8161 /* The event PTID. */
8165 /* If stopp for a thread event, this is the thread that caused the
8167 struct thread_info
*thread
;
8169 /* The inferior that caused the stop. */
8173 /* Returns a new stop context. If stopped for a thread event, this
8174 takes a strong reference to the thread. */
8176 static struct stop_context
*
8177 save_stop_context (void)
8179 struct stop_context
*sc
= XNEW (struct stop_context
);
8181 sc
->stop_id
= get_stop_id ();
8182 sc
->ptid
= inferior_ptid
;
8183 sc
->inf_num
= current_inferior ()->num
;
8185 if (!ptid_equal (inferior_ptid
, null_ptid
))
8187 /* Take a strong reference so that the thread can't be deleted
8189 sc
->thread
= inferior_thread ();
8190 sc
->thread
->refcount
++;
8198 /* Release a stop context previously created with save_stop_context.
8199 Releases the strong reference to the thread as well. */
8202 release_stop_context_cleanup (void *arg
)
8204 struct stop_context
*sc
= (struct stop_context
*) arg
;
8206 if (sc
->thread
!= NULL
)
8207 sc
->thread
->refcount
--;
8211 /* Return true if the current context no longer matches the saved stop
8215 stop_context_changed (struct stop_context
*prev
)
8217 if (!ptid_equal (prev
->ptid
, inferior_ptid
))
8219 if (prev
->inf_num
!= current_inferior ()->num
)
8221 if (prev
->thread
!= NULL
&& prev
->thread
->state
!= THREAD_STOPPED
)
8223 if (get_stop_id () != prev
->stop_id
)
8233 struct target_waitstatus last
;
8235 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
8237 struct switch_thru_all_uis state
;
8239 get_last_target_status (&last_ptid
, &last
);
8243 /* If an exception is thrown from this point on, make sure to
8244 propagate GDB's knowledge of the executing state to the
8245 frontend/user running state. A QUIT is an easy exception to see
8246 here, so do this before any filtered output. */
8248 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
8249 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8250 || last
.kind
== TARGET_WAITKIND_EXITED
)
8252 /* On some targets, we may still have live threads in the
8253 inferior when we get a process exit event. E.g., for
8254 "checkpoint", when the current checkpoint/fork exits,
8255 linux-fork.c automatically switches to another fork from
8256 within target_mourn_inferior. */
8257 if (!ptid_equal (inferior_ptid
, null_ptid
))
8259 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
8260 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
8263 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8264 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
8266 /* As we're presenting a stop, and potentially removing breakpoints,
8267 update the thread list so we can tell whether there are threads
8268 running on the target. With target remote, for example, we can
8269 only learn about new threads when we explicitly update the thread
8270 list. Do this before notifying the interpreters about signal
8271 stops, end of stepping ranges, etc., so that the "new thread"
8272 output is emitted before e.g., "Program received signal FOO",
8273 instead of after. */
8274 update_thread_list ();
8276 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8277 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
8279 /* As with the notification of thread events, we want to delay
8280 notifying the user that we've switched thread context until
8281 the inferior actually stops.
8283 There's no point in saying anything if the inferior has exited.
8284 Note that SIGNALLED here means "exited with a signal", not
8285 "received a signal".
8287 Also skip saying anything in non-stop mode. In that mode, as we
8288 don't want GDB to switch threads behind the user's back, to avoid
8289 races where the user is typing a command to apply to thread x,
8290 but GDB switches to thread y before the user finishes entering
8291 the command, fetch_inferior_event installs a cleanup to restore
8292 the current thread back to the thread the user had selected right
8293 after this event is handled, so we're not really switching, only
8294 informing of a stop. */
8296 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
8297 && target_has_execution
8298 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8299 && last
.kind
!= TARGET_WAITKIND_EXITED
8300 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8302 SWITCH_THRU_ALL_UIS (state
)
8304 target_terminal_ours_for_output ();
8305 printf_filtered (_("[Switching to %s]\n"),
8306 target_pid_to_str (inferior_ptid
));
8307 annotate_thread_changed ();
8309 previous_inferior_ptid
= inferior_ptid
;
8312 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8314 SWITCH_THRU_ALL_UIS (state
)
8315 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8317 target_terminal_ours_for_output ();
8318 printf_filtered (_("No unwaited-for children left.\n"));
8322 /* Note: this depends on the update_thread_list call above. */
8323 maybe_remove_breakpoints ();
8325 /* If an auto-display called a function and that got a signal,
8326 delete that auto-display to avoid an infinite recursion. */
8328 if (stopped_by_random_signal
)
8329 disable_current_display ();
8331 SWITCH_THRU_ALL_UIS (state
)
8333 async_enable_stdin ();
8336 /* Let the user/frontend see the threads as stopped. */
8337 do_cleanups (old_chain
);
8339 /* Select innermost stack frame - i.e., current frame is frame 0,
8340 and current location is based on that. Handle the case where the
8341 dummy call is returning after being stopped. E.g. the dummy call
8342 previously hit a breakpoint. (If the dummy call returns
8343 normally, we won't reach here.) Do this before the stop hook is
8344 run, so that it doesn't get to see the temporary dummy frame,
8345 which is not where we'll present the stop. */
8346 if (has_stack_frames ())
8348 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8350 /* Pop the empty frame that contains the stack dummy. This
8351 also restores inferior state prior to the call (struct
8352 infcall_suspend_state). */
8353 struct frame_info
*frame
= get_current_frame ();
8355 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8357 /* frame_pop calls reinit_frame_cache as the last thing it
8358 does which means there's now no selected frame. */
8361 select_frame (get_current_frame ());
8363 /* Set the current source location. */
8364 set_current_sal_from_frame (get_current_frame ());
8367 /* Look up the hook_stop and run it (CLI internally handles problem
8368 of stop_command's pre-hook not existing). */
8369 if (stop_command
!= NULL
)
8371 struct stop_context
*saved_context
= save_stop_context ();
8372 struct cleanup
*old_chain
8373 = make_cleanup (release_stop_context_cleanup
, saved_context
);
8375 catch_errors (hook_stop_stub
, stop_command
,
8376 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
8378 /* If the stop hook resumes the target, then there's no point in
8379 trying to notify about the previous stop; its context is
8380 gone. Likewise if the command switches thread or inferior --
8381 the observers would print a stop for the wrong
8383 if (stop_context_changed (saved_context
))
8385 do_cleanups (old_chain
);
8388 do_cleanups (old_chain
);
8391 /* Notify observers about the stop. This is where the interpreters
8392 print the stop event. */
8393 if (!ptid_equal (inferior_ptid
, null_ptid
))
8394 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
8397 observer_notify_normal_stop (NULL
, stop_print_frame
);
8399 annotate_stopped ();
8401 if (target_has_execution
)
8403 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8404 && last
.kind
!= TARGET_WAITKIND_EXITED
)
8405 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8406 Delete any breakpoint that is to be deleted at the next stop. */
8407 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8410 /* Try to get rid of automatically added inferiors that are no
8411 longer needed. Keeping those around slows down things linearly.
8412 Note that this never removes the current inferior. */
8419 hook_stop_stub (void *cmd
)
8421 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
8426 signal_stop_state (int signo
)
8428 return signal_stop
[signo
];
8432 signal_print_state (int signo
)
8434 return signal_print
[signo
];
8438 signal_pass_state (int signo
)
8440 return signal_program
[signo
];
8444 signal_cache_update (int signo
)
8448 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8449 signal_cache_update (signo
);
8454 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8455 && signal_print
[signo
] == 0
8456 && signal_program
[signo
] == 1
8457 && signal_catch
[signo
] == 0);
8461 signal_stop_update (int signo
, int state
)
8463 int ret
= signal_stop
[signo
];
8465 signal_stop
[signo
] = state
;
8466 signal_cache_update (signo
);
8471 signal_print_update (int signo
, int state
)
8473 int ret
= signal_print
[signo
];
8475 signal_print
[signo
] = state
;
8476 signal_cache_update (signo
);
8481 signal_pass_update (int signo
, int state
)
8483 int ret
= signal_program
[signo
];
8485 signal_program
[signo
] = state
;
8486 signal_cache_update (signo
);
8490 /* Update the global 'signal_catch' from INFO and notify the
8494 signal_catch_update (const unsigned int *info
)
8498 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8499 signal_catch
[i
] = info
[i
] > 0;
8500 signal_cache_update (-1);
8501 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8505 sig_print_header (void)
8507 printf_filtered (_("Signal Stop\tPrint\tPass "
8508 "to program\tDescription\n"));
8512 sig_print_info (enum gdb_signal oursig
)
8514 const char *name
= gdb_signal_to_name (oursig
);
8515 int name_padding
= 13 - strlen (name
);
8517 if (name_padding
<= 0)
8520 printf_filtered ("%s", name
);
8521 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8522 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8523 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8524 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8525 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8528 /* Specify how various signals in the inferior should be handled. */
8531 handle_command (char *args
, int from_tty
)
8534 int digits
, wordlen
;
8535 int sigfirst
, signum
, siglast
;
8536 enum gdb_signal oursig
;
8539 unsigned char *sigs
;
8540 struct cleanup
*old_chain
;
8544 error_no_arg (_("signal to handle"));
8547 /* Allocate and zero an array of flags for which signals to handle. */
8549 nsigs
= (int) GDB_SIGNAL_LAST
;
8550 sigs
= (unsigned char *) alloca (nsigs
);
8551 memset (sigs
, 0, nsigs
);
8553 /* Break the command line up into args. */
8555 argv
= gdb_buildargv (args
);
8556 old_chain
= make_cleanup_freeargv (argv
);
8558 /* Walk through the args, looking for signal oursigs, signal names, and
8559 actions. Signal numbers and signal names may be interspersed with
8560 actions, with the actions being performed for all signals cumulatively
8561 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8563 while (*argv
!= NULL
)
8565 wordlen
= strlen (*argv
);
8566 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
8570 sigfirst
= siglast
= -1;
8572 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
8574 /* Apply action to all signals except those used by the
8575 debugger. Silently skip those. */
8578 siglast
= nsigs
- 1;
8580 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
8582 SET_SIGS (nsigs
, sigs
, signal_stop
);
8583 SET_SIGS (nsigs
, sigs
, signal_print
);
8585 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
8587 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8589 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
8591 SET_SIGS (nsigs
, sigs
, signal_print
);
8593 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
8595 SET_SIGS (nsigs
, sigs
, signal_program
);
8597 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
8599 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8601 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
8603 SET_SIGS (nsigs
, sigs
, signal_program
);
8605 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
8607 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8608 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8610 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
8612 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8614 else if (digits
> 0)
8616 /* It is numeric. The numeric signal refers to our own
8617 internal signal numbering from target.h, not to host/target
8618 signal number. This is a feature; users really should be
8619 using symbolic names anyway, and the common ones like
8620 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8622 sigfirst
= siglast
= (int)
8623 gdb_signal_from_command (atoi (*argv
));
8624 if ((*argv
)[digits
] == '-')
8627 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
8629 if (sigfirst
> siglast
)
8631 /* Bet he didn't figure we'd think of this case... */
8639 oursig
= gdb_signal_from_name (*argv
);
8640 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8642 sigfirst
= siglast
= (int) oursig
;
8646 /* Not a number and not a recognized flag word => complain. */
8647 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
8651 /* If any signal numbers or symbol names were found, set flags for
8652 which signals to apply actions to. */
8654 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8656 switch ((enum gdb_signal
) signum
)
8658 case GDB_SIGNAL_TRAP
:
8659 case GDB_SIGNAL_INT
:
8660 if (!allsigs
&& !sigs
[signum
])
8662 if (query (_("%s is used by the debugger.\n\
8663 Are you sure you want to change it? "),
8664 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8670 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8671 gdb_flush (gdb_stdout
);
8676 case GDB_SIGNAL_DEFAULT
:
8677 case GDB_SIGNAL_UNKNOWN
:
8678 /* Make sure that "all" doesn't print these. */
8689 for (signum
= 0; signum
< nsigs
; signum
++)
8692 signal_cache_update (-1);
8693 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8694 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8698 /* Show the results. */
8699 sig_print_header ();
8700 for (; signum
< nsigs
; signum
++)
8702 sig_print_info ((enum gdb_signal
) signum
);
8708 do_cleanups (old_chain
);
8711 /* Complete the "handle" command. */
8713 static VEC (char_ptr
) *
8714 handle_completer (struct cmd_list_element
*ignore
,
8715 const char *text
, const char *word
)
8717 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
8718 static const char * const keywords
[] =
8732 vec_signals
= signal_completer (ignore
, text
, word
);
8733 vec_keywords
= complete_on_enum (keywords
, word
, word
);
8735 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
8736 VEC_free (char_ptr
, vec_signals
);
8737 VEC_free (char_ptr
, vec_keywords
);
8742 gdb_signal_from_command (int num
)
8744 if (num
>= 1 && num
<= 15)
8745 return (enum gdb_signal
) num
;
8746 error (_("Only signals 1-15 are valid as numeric signals.\n\
8747 Use \"info signals\" for a list of symbolic signals."));
8750 /* Print current contents of the tables set by the handle command.
8751 It is possible we should just be printing signals actually used
8752 by the current target (but for things to work right when switching
8753 targets, all signals should be in the signal tables). */
8756 signals_info (char *signum_exp
, int from_tty
)
8758 enum gdb_signal oursig
;
8760 sig_print_header ();
8764 /* First see if this is a symbol name. */
8765 oursig
= gdb_signal_from_name (signum_exp
);
8766 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8768 /* No, try numeric. */
8770 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8772 sig_print_info (oursig
);
8776 printf_filtered ("\n");
8777 /* These ugly casts brought to you by the native VAX compiler. */
8778 for (oursig
= GDB_SIGNAL_FIRST
;
8779 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8780 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8784 if (oursig
!= GDB_SIGNAL_UNKNOWN
8785 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8786 sig_print_info (oursig
);
8789 printf_filtered (_("\nUse the \"handle\" command "
8790 "to change these tables.\n"));
8793 /* The $_siginfo convenience variable is a bit special. We don't know
8794 for sure the type of the value until we actually have a chance to
8795 fetch the data. The type can change depending on gdbarch, so it is
8796 also dependent on which thread you have selected.
8798 1. making $_siginfo be an internalvar that creates a new value on
8801 2. making the value of $_siginfo be an lval_computed value. */
8803 /* This function implements the lval_computed support for reading a
8807 siginfo_value_read (struct value
*v
)
8809 LONGEST transferred
;
8811 /* If we can access registers, so can we access $_siginfo. Likewise
8813 validate_registers_access ();
8816 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8818 value_contents_all_raw (v
),
8820 TYPE_LENGTH (value_type (v
)));
8822 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8823 error (_("Unable to read siginfo"));
8826 /* This function implements the lval_computed support for writing a
8830 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8832 LONGEST transferred
;
8834 /* If we can access registers, so can we access $_siginfo. Likewise
8836 validate_registers_access ();
8838 transferred
= target_write (¤t_target
,
8839 TARGET_OBJECT_SIGNAL_INFO
,
8841 value_contents_all_raw (fromval
),
8843 TYPE_LENGTH (value_type (fromval
)));
8845 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8846 error (_("Unable to write siginfo"));
8849 static const struct lval_funcs siginfo_value_funcs
=
8855 /* Return a new value with the correct type for the siginfo object of
8856 the current thread using architecture GDBARCH. Return a void value
8857 if there's no object available. */
8859 static struct value
*
8860 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8863 if (target_has_stack
8864 && !ptid_equal (inferior_ptid
, null_ptid
)
8865 && gdbarch_get_siginfo_type_p (gdbarch
))
8867 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8869 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8872 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8876 /* infcall_suspend_state contains state about the program itself like its
8877 registers and any signal it received when it last stopped.
8878 This state must be restored regardless of how the inferior function call
8879 ends (either successfully, or after it hits a breakpoint or signal)
8880 if the program is to properly continue where it left off. */
8882 struct infcall_suspend_state
8884 struct thread_suspend_state thread_suspend
;
8888 struct regcache
*registers
;
8890 /* Format of SIGINFO_DATA or NULL if it is not present. */
8891 struct gdbarch
*siginfo_gdbarch
;
8893 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8894 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8895 content would be invalid. */
8896 gdb_byte
*siginfo_data
;
8899 struct infcall_suspend_state
*
8900 save_infcall_suspend_state (void)
8902 struct infcall_suspend_state
*inf_state
;
8903 struct thread_info
*tp
= inferior_thread ();
8904 struct regcache
*regcache
= get_current_regcache ();
8905 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8906 gdb_byte
*siginfo_data
= NULL
;
8908 if (gdbarch_get_siginfo_type_p (gdbarch
))
8910 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8911 size_t len
= TYPE_LENGTH (type
);
8912 struct cleanup
*back_to
;
8914 siginfo_data
= (gdb_byte
*) xmalloc (len
);
8915 back_to
= make_cleanup (xfree
, siginfo_data
);
8917 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8918 siginfo_data
, 0, len
) == len
)
8919 discard_cleanups (back_to
);
8922 /* Errors ignored. */
8923 do_cleanups (back_to
);
8924 siginfo_data
= NULL
;
8928 inf_state
= XCNEW (struct infcall_suspend_state
);
8932 inf_state
->siginfo_gdbarch
= gdbarch
;
8933 inf_state
->siginfo_data
= siginfo_data
;
8936 inf_state
->thread_suspend
= tp
->suspend
;
8938 /* run_inferior_call will not use the signal due to its `proceed' call with
8939 GDB_SIGNAL_0 anyway. */
8940 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8942 inf_state
->stop_pc
= stop_pc
;
8944 inf_state
->registers
= regcache_dup (regcache
);
8949 /* Restore inferior session state to INF_STATE. */
8952 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8954 struct thread_info
*tp
= inferior_thread ();
8955 struct regcache
*regcache
= get_current_regcache ();
8956 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8958 tp
->suspend
= inf_state
->thread_suspend
;
8960 stop_pc
= inf_state
->stop_pc
;
8962 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8964 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8966 /* Errors ignored. */
8967 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8968 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8971 /* The inferior can be gone if the user types "print exit(0)"
8972 (and perhaps other times). */
8973 if (target_has_execution
)
8974 /* NB: The register write goes through to the target. */
8975 regcache_cpy (regcache
, inf_state
->registers
);
8977 discard_infcall_suspend_state (inf_state
);
8981 do_restore_infcall_suspend_state_cleanup (void *state
)
8983 restore_infcall_suspend_state ((struct infcall_suspend_state
*) state
);
8987 make_cleanup_restore_infcall_suspend_state
8988 (struct infcall_suspend_state
*inf_state
)
8990 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
8994 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8996 regcache_xfree (inf_state
->registers
);
8997 xfree (inf_state
->siginfo_data
);
9002 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
9004 return inf_state
->registers
;
9007 /* infcall_control_state contains state regarding gdb's control of the
9008 inferior itself like stepping control. It also contains session state like
9009 the user's currently selected frame. */
9011 struct infcall_control_state
9013 struct thread_control_state thread_control
;
9014 struct inferior_control_state inferior_control
;
9017 enum stop_stack_kind stop_stack_dummy
;
9018 int stopped_by_random_signal
;
9020 /* ID if the selected frame when the inferior function call was made. */
9021 struct frame_id selected_frame_id
;
9024 /* Save all of the information associated with the inferior<==>gdb
9027 struct infcall_control_state
*
9028 save_infcall_control_state (void)
9030 struct infcall_control_state
*inf_status
=
9031 XNEW (struct infcall_control_state
);
9032 struct thread_info
*tp
= inferior_thread ();
9033 struct inferior
*inf
= current_inferior ();
9035 inf_status
->thread_control
= tp
->control
;
9036 inf_status
->inferior_control
= inf
->control
;
9038 tp
->control
.step_resume_breakpoint
= NULL
;
9039 tp
->control
.exception_resume_breakpoint
= NULL
;
9041 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9042 chain. If caller's caller is walking the chain, they'll be happier if we
9043 hand them back the original chain when restore_infcall_control_state is
9045 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9048 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9049 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9051 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
9057 restore_selected_frame (void *args
)
9059 struct frame_id
*fid
= (struct frame_id
*) args
;
9060 struct frame_info
*frame
;
9062 frame
= frame_find_by_id (*fid
);
9064 /* If inf_status->selected_frame_id is NULL, there was no previously
9068 warning (_("Unable to restore previously selected frame."));
9072 select_frame (frame
);
9077 /* Restore inferior session state to INF_STATUS. */
9080 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9082 struct thread_info
*tp
= inferior_thread ();
9083 struct inferior
*inf
= current_inferior ();
9085 if (tp
->control
.step_resume_breakpoint
)
9086 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9088 if (tp
->control
.exception_resume_breakpoint
)
9089 tp
->control
.exception_resume_breakpoint
->disposition
9090 = disp_del_at_next_stop
;
9092 /* Handle the bpstat_copy of the chain. */
9093 bpstat_clear (&tp
->control
.stop_bpstat
);
9095 tp
->control
= inf_status
->thread_control
;
9096 inf
->control
= inf_status
->inferior_control
;
9099 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9100 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9102 if (target_has_stack
)
9104 /* The point of catch_errors is that if the stack is clobbered,
9105 walking the stack might encounter a garbage pointer and
9106 error() trying to dereference it. */
9108 (restore_selected_frame
, &inf_status
->selected_frame_id
,
9109 "Unable to restore previously selected frame:\n",
9110 RETURN_MASK_ERROR
) == 0)
9111 /* Error in restoring the selected frame. Select the innermost
9113 select_frame (get_current_frame ());
9120 do_restore_infcall_control_state_cleanup (void *sts
)
9122 restore_infcall_control_state ((struct infcall_control_state
*) sts
);
9126 make_cleanup_restore_infcall_control_state
9127 (struct infcall_control_state
*inf_status
)
9129 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
9133 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9135 if (inf_status
->thread_control
.step_resume_breakpoint
)
9136 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9137 = disp_del_at_next_stop
;
9139 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9140 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9141 = disp_del_at_next_stop
;
9143 /* See save_infcall_control_state for info on stop_bpstat. */
9144 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9149 /* restore_inferior_ptid() will be used by the cleanup machinery
9150 to restore the inferior_ptid value saved in a call to
9151 save_inferior_ptid(). */
9154 restore_inferior_ptid (void *arg
)
9156 ptid_t
*saved_ptid_ptr
= (ptid_t
*) arg
;
9158 inferior_ptid
= *saved_ptid_ptr
;
9162 /* Save the value of inferior_ptid so that it may be restored by a
9163 later call to do_cleanups(). Returns the struct cleanup pointer
9164 needed for later doing the cleanup. */
9167 save_inferior_ptid (void)
9169 ptid_t
*saved_ptid_ptr
= XNEW (ptid_t
);
9171 *saved_ptid_ptr
= inferior_ptid
;
9172 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
9178 clear_exit_convenience_vars (void)
9180 clear_internalvar (lookup_internalvar ("_exitsignal"));
9181 clear_internalvar (lookup_internalvar ("_exitcode"));
9185 /* User interface for reverse debugging:
9186 Set exec-direction / show exec-direction commands
9187 (returns error unless target implements to_set_exec_direction method). */
9189 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9190 static const char exec_forward
[] = "forward";
9191 static const char exec_reverse
[] = "reverse";
9192 static const char *exec_direction
= exec_forward
;
9193 static const char *const exec_direction_names
[] = {
9200 set_exec_direction_func (char *args
, int from_tty
,
9201 struct cmd_list_element
*cmd
)
9203 if (target_can_execute_reverse
)
9205 if (!strcmp (exec_direction
, exec_forward
))
9206 execution_direction
= EXEC_FORWARD
;
9207 else if (!strcmp (exec_direction
, exec_reverse
))
9208 execution_direction
= EXEC_REVERSE
;
9212 exec_direction
= exec_forward
;
9213 error (_("Target does not support this operation."));
9218 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9219 struct cmd_list_element
*cmd
, const char *value
)
9221 switch (execution_direction
) {
9223 fprintf_filtered (out
, _("Forward.\n"));
9226 fprintf_filtered (out
, _("Reverse.\n"));
9229 internal_error (__FILE__
, __LINE__
,
9230 _("bogus execution_direction value: %d"),
9231 (int) execution_direction
);
9236 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9237 struct cmd_list_element
*c
, const char *value
)
9239 fprintf_filtered (file
, _("Resuming the execution of threads "
9240 "of all processes is %s.\n"), value
);
9243 /* Implementation of `siginfo' variable. */
9245 static const struct internalvar_funcs siginfo_funcs
=
9252 /* Callback for infrun's target events source. This is marked when a
9253 thread has a pending status to process. */
9256 infrun_async_inferior_event_handler (gdb_client_data data
)
9258 inferior_event_handler (INF_REG_EVENT
, NULL
);
9262 _initialize_infrun (void)
9266 struct cmd_list_element
*c
;
9268 /* Register extra event sources in the event loop. */
9269 infrun_async_inferior_event_token
9270 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
9272 add_info ("signals", signals_info
, _("\
9273 What debugger does when program gets various signals.\n\
9274 Specify a signal as argument to print info on that signal only."));
9275 add_info_alias ("handle", "signals", 0);
9277 c
= add_com ("handle", class_run
, handle_command
, _("\
9278 Specify how to handle signals.\n\
9279 Usage: handle SIGNAL [ACTIONS]\n\
9280 Args are signals and actions to apply to those signals.\n\
9281 If no actions are specified, the current settings for the specified signals\n\
9282 will be displayed instead.\n\
9284 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9285 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9286 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9287 The special arg \"all\" is recognized to mean all signals except those\n\
9288 used by the debugger, typically SIGTRAP and SIGINT.\n\
9290 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9291 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9292 Stop means reenter debugger if this signal happens (implies print).\n\
9293 Print means print a message if this signal happens.\n\
9294 Pass means let program see this signal; otherwise program doesn't know.\n\
9295 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9296 Pass and Stop may be combined.\n\
9298 Multiple signals may be specified. Signal numbers and signal names\n\
9299 may be interspersed with actions, with the actions being performed for\n\
9300 all signals cumulatively specified."));
9301 set_cmd_completer (c
, handle_completer
);
9304 stop_command
= add_cmd ("stop", class_obscure
,
9305 not_just_help_class_command
, _("\
9306 There is no `stop' command, but you can set a hook on `stop'.\n\
9307 This allows you to set a list of commands to be run each time execution\n\
9308 of the program stops."), &cmdlist
);
9310 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
9311 Set inferior debugging."), _("\
9312 Show inferior debugging."), _("\
9313 When non-zero, inferior specific debugging is enabled."),
9316 &setdebuglist
, &showdebuglist
);
9318 add_setshow_boolean_cmd ("displaced", class_maintenance
,
9319 &debug_displaced
, _("\
9320 Set displaced stepping debugging."), _("\
9321 Show displaced stepping debugging."), _("\
9322 When non-zero, displaced stepping specific debugging is enabled."),
9324 show_debug_displaced
,
9325 &setdebuglist
, &showdebuglist
);
9327 add_setshow_boolean_cmd ("non-stop", no_class
,
9329 Set whether gdb controls the inferior in non-stop mode."), _("\
9330 Show whether gdb controls the inferior in non-stop mode."), _("\
9331 When debugging a multi-threaded program and this setting is\n\
9332 off (the default, also called all-stop mode), when one thread stops\n\
9333 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9334 all other threads in the program while you interact with the thread of\n\
9335 interest. When you continue or step a thread, you can allow the other\n\
9336 threads to run, or have them remain stopped, but while you inspect any\n\
9337 thread's state, all threads stop.\n\
9339 In non-stop mode, when one thread stops, other threads can continue\n\
9340 to run freely. You'll be able to step each thread independently,\n\
9341 leave it stopped or free to run as needed."),
9347 numsigs
= (int) GDB_SIGNAL_LAST
;
9348 signal_stop
= XNEWVEC (unsigned char, numsigs
);
9349 signal_print
= XNEWVEC (unsigned char, numsigs
);
9350 signal_program
= XNEWVEC (unsigned char, numsigs
);
9351 signal_catch
= XNEWVEC (unsigned char, numsigs
);
9352 signal_pass
= XNEWVEC (unsigned char, numsigs
);
9353 for (i
= 0; i
< numsigs
; i
++)
9356 signal_print
[i
] = 1;
9357 signal_program
[i
] = 1;
9358 signal_catch
[i
] = 0;
9361 /* Signals caused by debugger's own actions should not be given to
9362 the program afterwards.
9364 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9365 explicitly specifies that it should be delivered to the target
9366 program. Typically, that would occur when a user is debugging a
9367 target monitor on a simulator: the target monitor sets a
9368 breakpoint; the simulator encounters this breakpoint and halts
9369 the simulation handing control to GDB; GDB, noting that the stop
9370 address doesn't map to any known breakpoint, returns control back
9371 to the simulator; the simulator then delivers the hardware
9372 equivalent of a GDB_SIGNAL_TRAP to the program being
9374 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9375 signal_program
[GDB_SIGNAL_INT
] = 0;
9377 /* Signals that are not errors should not normally enter the debugger. */
9378 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9379 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9380 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9381 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9382 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9383 signal_print
[GDB_SIGNAL_PROF
] = 0;
9384 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9385 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9386 signal_stop
[GDB_SIGNAL_IO
] = 0;
9387 signal_print
[GDB_SIGNAL_IO
] = 0;
9388 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9389 signal_print
[GDB_SIGNAL_POLL
] = 0;
9390 signal_stop
[GDB_SIGNAL_URG
] = 0;
9391 signal_print
[GDB_SIGNAL_URG
] = 0;
9392 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9393 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9394 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9395 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9397 /* These signals are used internally by user-level thread
9398 implementations. (See signal(5) on Solaris.) Like the above
9399 signals, a healthy program receives and handles them as part of
9400 its normal operation. */
9401 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9402 signal_print
[GDB_SIGNAL_LWP
] = 0;
9403 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9404 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9405 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9406 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9408 /* Update cached state. */
9409 signal_cache_update (-1);
9411 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9412 &stop_on_solib_events
, _("\
9413 Set stopping for shared library events."), _("\
9414 Show stopping for shared library events."), _("\
9415 If nonzero, gdb will give control to the user when the dynamic linker\n\
9416 notifies gdb of shared library events. The most common event of interest\n\
9417 to the user would be loading/unloading of a new library."),
9418 set_stop_on_solib_events
,
9419 show_stop_on_solib_events
,
9420 &setlist
, &showlist
);
9422 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9423 follow_fork_mode_kind_names
,
9424 &follow_fork_mode_string
, _("\
9425 Set debugger response to a program call of fork or vfork."), _("\
9426 Show debugger response to a program call of fork or vfork."), _("\
9427 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9428 parent - the original process is debugged after a fork\n\
9429 child - the new process is debugged after a fork\n\
9430 The unfollowed process will continue to run.\n\
9431 By default, the debugger will follow the parent process."),
9433 show_follow_fork_mode_string
,
9434 &setlist
, &showlist
);
9436 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9437 follow_exec_mode_names
,
9438 &follow_exec_mode_string
, _("\
9439 Set debugger response to a program call of exec."), _("\
9440 Show debugger response to a program call of exec."), _("\
9441 An exec call replaces the program image of a process.\n\
9443 follow-exec-mode can be:\n\
9445 new - the debugger creates a new inferior and rebinds the process\n\
9446 to this new inferior. The program the process was running before\n\
9447 the exec call can be restarted afterwards by restarting the original\n\
9450 same - the debugger keeps the process bound to the same inferior.\n\
9451 The new executable image replaces the previous executable loaded in\n\
9452 the inferior. Restarting the inferior after the exec call restarts\n\
9453 the executable the process was running after the exec call.\n\
9455 By default, the debugger will use the same inferior."),
9457 show_follow_exec_mode_string
,
9458 &setlist
, &showlist
);
9460 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9461 scheduler_enums
, &scheduler_mode
, _("\
9462 Set mode for locking scheduler during execution."), _("\
9463 Show mode for locking scheduler during execution."), _("\
9464 off == no locking (threads may preempt at any time)\n\
9465 on == full locking (no thread except the current thread may run)\n\
9466 This applies to both normal execution and replay mode.\n\
9467 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9468 In this mode, other threads may run during other commands.\n\
9469 This applies to both normal execution and replay mode.\n\
9470 replay == scheduler locked in replay mode and unlocked during normal execution."),
9471 set_schedlock_func
, /* traps on target vector */
9472 show_scheduler_mode
,
9473 &setlist
, &showlist
);
9475 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9476 Set mode for resuming threads of all processes."), _("\
9477 Show mode for resuming threads of all processes."), _("\
9478 When on, execution commands (such as 'continue' or 'next') resume all\n\
9479 threads of all processes. When off (which is the default), execution\n\
9480 commands only resume the threads of the current process. The set of\n\
9481 threads that are resumed is further refined by the scheduler-locking\n\
9482 mode (see help set scheduler-locking)."),
9484 show_schedule_multiple
,
9485 &setlist
, &showlist
);
9487 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9488 Set mode of the step operation."), _("\
9489 Show mode of the step operation."), _("\
9490 When set, doing a step over a function without debug line information\n\
9491 will stop at the first instruction of that function. Otherwise, the\n\
9492 function is skipped and the step command stops at a different source line."),
9494 show_step_stop_if_no_debug
,
9495 &setlist
, &showlist
);
9497 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9498 &can_use_displaced_stepping
, _("\
9499 Set debugger's willingness to use displaced stepping."), _("\
9500 Show debugger's willingness to use displaced stepping."), _("\
9501 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9502 supported by the target architecture. If off, gdb will not use displaced\n\
9503 stepping to step over breakpoints, even if such is supported by the target\n\
9504 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9505 if the target architecture supports it and non-stop mode is active, but will not\n\
9506 use it in all-stop mode (see help set non-stop)."),
9508 show_can_use_displaced_stepping
,
9509 &setlist
, &showlist
);
9511 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9512 &exec_direction
, _("Set direction of execution.\n\
9513 Options are 'forward' or 'reverse'."),
9514 _("Show direction of execution (forward/reverse)."),
9515 _("Tells gdb whether to execute forward or backward."),
9516 set_exec_direction_func
, show_exec_direction_func
,
9517 &setlist
, &showlist
);
9519 /* Set/show detach-on-fork: user-settable mode. */
9521 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9522 Set whether gdb will detach the child of a fork."), _("\
9523 Show whether gdb will detach the child of a fork."), _("\
9524 Tells gdb whether to detach the child of a fork."),
9525 NULL
, NULL
, &setlist
, &showlist
);
9527 /* Set/show disable address space randomization mode. */
9529 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9530 &disable_randomization
, _("\
9531 Set disabling of debuggee's virtual address space randomization."), _("\
9532 Show disabling of debuggee's virtual address space randomization."), _("\
9533 When this mode is on (which is the default), randomization of the virtual\n\
9534 address space is disabled. Standalone programs run with the randomization\n\
9535 enabled by default on some platforms."),
9536 &set_disable_randomization
,
9537 &show_disable_randomization
,
9538 &setlist
, &showlist
);
9540 /* ptid initializations */
9541 inferior_ptid
= null_ptid
;
9542 target_last_wait_ptid
= minus_one_ptid
;
9544 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
9545 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
9546 observer_attach_thread_exit (infrun_thread_thread_exit
);
9547 observer_attach_inferior_exit (infrun_inferior_exit
);
9549 /* Explicitly create without lookup, since that tries to create a
9550 value with a void typed value, and when we get here, gdbarch
9551 isn't initialized yet. At this point, we're quite sure there
9552 isn't another convenience variable of the same name. */
9553 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9555 add_setshow_boolean_cmd ("observer", no_class
,
9556 &observer_mode_1
, _("\
9557 Set whether gdb controls the inferior in observer mode."), _("\
9558 Show whether gdb controls the inferior in observer mode."), _("\
9559 In observer mode, GDB can get data from the inferior, but not\n\
9560 affect its execution. Registers and memory may not be changed,\n\
9561 breakpoints may not be set, and the program cannot be interrupted\n\