1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2015 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 /* In asynchronous mode, but simulating synchronous execution. */
157 int sync_execution
= 0;
159 /* proceed and normal_stop use this to notify the user when the
160 inferior stopped in a different thread than it had been running
163 static ptid_t previous_inferior_ptid
;
165 /* If set (default for legacy reasons), when following a fork, GDB
166 will detach from one of the fork branches, child or parent.
167 Exactly which branch is detached depends on 'set follow-fork-mode'
170 static int detach_fork
= 1;
172 int debug_displaced
= 0;
174 show_debug_displaced (struct ui_file
*file
, int from_tty
,
175 struct cmd_list_element
*c
, const char *value
)
177 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
180 unsigned int debug_infrun
= 0;
182 show_debug_infrun (struct ui_file
*file
, int from_tty
,
183 struct cmd_list_element
*c
, const char *value
)
185 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
189 /* Support for disabling address space randomization. */
191 int disable_randomization
= 1;
194 show_disable_randomization (struct ui_file
*file
, int from_tty
,
195 struct cmd_list_element
*c
, const char *value
)
197 if (target_supports_disable_randomization ())
198 fprintf_filtered (file
,
199 _("Disabling randomization of debuggee's "
200 "virtual address space is %s.\n"),
203 fputs_filtered (_("Disabling randomization of debuggee's "
204 "virtual address space is unsupported on\n"
205 "this platform.\n"), file
);
209 set_disable_randomization (char *args
, int from_tty
,
210 struct cmd_list_element
*c
)
212 if (!target_supports_disable_randomization ())
213 error (_("Disabling randomization of debuggee's "
214 "virtual address space is unsupported on\n"
218 /* User interface for non-stop mode. */
221 static int non_stop_1
= 0;
224 set_non_stop (char *args
, int from_tty
,
225 struct cmd_list_element
*c
)
227 if (target_has_execution
)
229 non_stop_1
= non_stop
;
230 error (_("Cannot change this setting while the inferior is running."));
233 non_stop
= non_stop_1
;
237 show_non_stop (struct ui_file
*file
, int from_tty
,
238 struct cmd_list_element
*c
, const char *value
)
240 fprintf_filtered (file
,
241 _("Controlling the inferior in non-stop mode is %s.\n"),
245 /* "Observer mode" is somewhat like a more extreme version of
246 non-stop, in which all GDB operations that might affect the
247 target's execution have been disabled. */
249 int observer_mode
= 0;
250 static int observer_mode_1
= 0;
253 set_observer_mode (char *args
, int from_tty
,
254 struct cmd_list_element
*c
)
256 if (target_has_execution
)
258 observer_mode_1
= observer_mode
;
259 error (_("Cannot change this setting while the inferior is running."));
262 observer_mode
= observer_mode_1
;
264 may_write_registers
= !observer_mode
;
265 may_write_memory
= !observer_mode
;
266 may_insert_breakpoints
= !observer_mode
;
267 may_insert_tracepoints
= !observer_mode
;
268 /* We can insert fast tracepoints in or out of observer mode,
269 but enable them if we're going into this mode. */
271 may_insert_fast_tracepoints
= 1;
272 may_stop
= !observer_mode
;
273 update_target_permissions ();
275 /* Going *into* observer mode we must force non-stop, then
276 going out we leave it that way. */
279 pagination_enabled
= 0;
280 non_stop
= non_stop_1
= 1;
284 printf_filtered (_("Observer mode is now %s.\n"),
285 (observer_mode
? "on" : "off"));
289 show_observer_mode (struct ui_file
*file
, int from_tty
,
290 struct cmd_list_element
*c
, const char *value
)
292 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
295 /* This updates the value of observer mode based on changes in
296 permissions. Note that we are deliberately ignoring the values of
297 may-write-registers and may-write-memory, since the user may have
298 reason to enable these during a session, for instance to turn on a
299 debugging-related global. */
302 update_observer_mode (void)
306 newval
= (!may_insert_breakpoints
307 && !may_insert_tracepoints
308 && may_insert_fast_tracepoints
312 /* Let the user know if things change. */
313 if (newval
!= observer_mode
)
314 printf_filtered (_("Observer mode is now %s.\n"),
315 (newval
? "on" : "off"));
317 observer_mode
= observer_mode_1
= newval
;
320 /* Tables of how to react to signals; the user sets them. */
322 static unsigned char *signal_stop
;
323 static unsigned char *signal_print
;
324 static unsigned char *signal_program
;
326 /* Table of signals that are registered with "catch signal". A
327 non-zero entry indicates that the signal is caught by some "catch
328 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
330 static unsigned char *signal_catch
;
332 /* Table of signals that the target may silently handle.
333 This is automatically determined from the flags above,
334 and simply cached here. */
335 static unsigned char *signal_pass
;
337 #define SET_SIGS(nsigs,sigs,flags) \
339 int signum = (nsigs); \
340 while (signum-- > 0) \
341 if ((sigs)[signum]) \
342 (flags)[signum] = 1; \
345 #define UNSET_SIGS(nsigs,sigs,flags) \
347 int signum = (nsigs); \
348 while (signum-- > 0) \
349 if ((sigs)[signum]) \
350 (flags)[signum] = 0; \
353 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
354 this function is to avoid exporting `signal_program'. */
357 update_signals_program_target (void)
359 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
362 /* Value to pass to target_resume() to cause all threads to resume. */
364 #define RESUME_ALL minus_one_ptid
366 /* Command list pointer for the "stop" placeholder. */
368 static struct cmd_list_element
*stop_command
;
370 /* Nonzero if we want to give control to the user when we're notified
371 of shared library events by the dynamic linker. */
372 int stop_on_solib_events
;
374 /* Enable or disable optional shared library event breakpoints
375 as appropriate when the above flag is changed. */
378 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
380 update_solib_breakpoints ();
384 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
385 struct cmd_list_element
*c
, const char *value
)
387 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
391 /* Nonzero after stop if current stack frame should be printed. */
393 static int stop_print_frame
;
395 /* This is a cached copy of the pid/waitstatus of the last event
396 returned by target_wait()/deprecated_target_wait_hook(). This
397 information is returned by get_last_target_status(). */
398 static ptid_t target_last_wait_ptid
;
399 static struct target_waitstatus target_last_waitstatus
;
401 static void context_switch (ptid_t ptid
);
403 void init_thread_stepping_state (struct thread_info
*tss
);
405 static const char follow_fork_mode_child
[] = "child";
406 static const char follow_fork_mode_parent
[] = "parent";
408 static const char *const follow_fork_mode_kind_names
[] = {
409 follow_fork_mode_child
,
410 follow_fork_mode_parent
,
414 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
416 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
417 struct cmd_list_element
*c
, const char *value
)
419 fprintf_filtered (file
,
420 _("Debugger response to a program "
421 "call of fork or vfork is \"%s\".\n"),
426 /* Handle changes to the inferior list based on the type of fork,
427 which process is being followed, and whether the other process
428 should be detached. On entry inferior_ptid must be the ptid of
429 the fork parent. At return inferior_ptid is the ptid of the
430 followed inferior. */
433 follow_fork_inferior (int follow_child
, int detach_fork
)
436 ptid_t parent_ptid
, child_ptid
;
438 has_vforked
= (inferior_thread ()->pending_follow
.kind
439 == TARGET_WAITKIND_VFORKED
);
440 parent_ptid
= inferior_ptid
;
441 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
444 && !non_stop
/* Non-stop always resumes both branches. */
445 && (!target_is_async_p () || sync_execution
)
446 && !(follow_child
|| detach_fork
|| sched_multi
))
448 /* The parent stays blocked inside the vfork syscall until the
449 child execs or exits. If we don't let the child run, then
450 the parent stays blocked. If we're telling the parent to run
451 in the foreground, the user will not be able to ctrl-c to get
452 back the terminal, effectively hanging the debug session. */
453 fprintf_filtered (gdb_stderr
, _("\
454 Can not resume the parent process over vfork in the foreground while\n\
455 holding the child stopped. Try \"set detach-on-fork\" or \
456 \"set schedule-multiple\".\n"));
457 /* FIXME output string > 80 columns. */
463 /* Detach new forked process? */
466 struct cleanup
*old_chain
;
468 /* Before detaching from the child, remove all breakpoints
469 from it. If we forked, then this has already been taken
470 care of by infrun.c. If we vforked however, any
471 breakpoint inserted in the parent is visible in the
472 child, even those added while stopped in a vfork
473 catchpoint. This will remove the breakpoints from the
474 parent also, but they'll be reinserted below. */
477 /* Keep breakpoints list in sync. */
478 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
481 if (info_verbose
|| debug_infrun
)
483 /* Ensure that we have a process ptid. */
484 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
486 target_terminal_ours_for_output ();
487 fprintf_filtered (gdb_stdlog
,
488 _("Detaching after %s from child %s.\n"),
489 has_vforked
? "vfork" : "fork",
490 target_pid_to_str (process_ptid
));
495 struct inferior
*parent_inf
, *child_inf
;
496 struct cleanup
*old_chain
;
498 /* Add process to GDB's tables. */
499 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
501 parent_inf
= current_inferior ();
502 child_inf
->attach_flag
= parent_inf
->attach_flag
;
503 copy_terminal_info (child_inf
, parent_inf
);
504 child_inf
->gdbarch
= parent_inf
->gdbarch
;
505 copy_inferior_target_desc_info (child_inf
, parent_inf
);
507 old_chain
= save_inferior_ptid ();
508 save_current_program_space ();
510 inferior_ptid
= child_ptid
;
511 add_thread (inferior_ptid
);
512 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
514 /* If this is a vfork child, then the address-space is
515 shared with the parent. */
518 child_inf
->pspace
= parent_inf
->pspace
;
519 child_inf
->aspace
= parent_inf
->aspace
;
521 /* The parent will be frozen until the child is done
522 with the shared region. Keep track of the
524 child_inf
->vfork_parent
= parent_inf
;
525 child_inf
->pending_detach
= 0;
526 parent_inf
->vfork_child
= child_inf
;
527 parent_inf
->pending_detach
= 0;
531 child_inf
->aspace
= new_address_space ();
532 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
533 child_inf
->removable
= 1;
534 set_current_program_space (child_inf
->pspace
);
535 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
537 /* Let the shared library layer (e.g., solib-svr4) learn
538 about this new process, relocate the cloned exec, pull
539 in shared libraries, and install the solib event
540 breakpoint. If a "cloned-VM" event was propagated
541 better throughout the core, this wouldn't be
543 solib_create_inferior_hook (0);
546 do_cleanups (old_chain
);
551 struct inferior
*parent_inf
;
553 parent_inf
= current_inferior ();
555 /* If we detached from the child, then we have to be careful
556 to not insert breakpoints in the parent until the child
557 is done with the shared memory region. However, if we're
558 staying attached to the child, then we can and should
559 insert breakpoints, so that we can debug it. A
560 subsequent child exec or exit is enough to know when does
561 the child stops using the parent's address space. */
562 parent_inf
->waiting_for_vfork_done
= detach_fork
;
563 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
568 /* Follow the child. */
569 struct inferior
*parent_inf
, *child_inf
;
570 struct program_space
*parent_pspace
;
572 if (info_verbose
|| debug_infrun
)
574 target_terminal_ours_for_output ();
575 fprintf_filtered (gdb_stdlog
,
576 _("Attaching after %s %s to child %s.\n"),
577 target_pid_to_str (parent_ptid
),
578 has_vforked
? "vfork" : "fork",
579 target_pid_to_str (child_ptid
));
582 /* Add the new inferior first, so that the target_detach below
583 doesn't unpush the target. */
585 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
587 parent_inf
= current_inferior ();
588 child_inf
->attach_flag
= parent_inf
->attach_flag
;
589 copy_terminal_info (child_inf
, parent_inf
);
590 child_inf
->gdbarch
= parent_inf
->gdbarch
;
591 copy_inferior_target_desc_info (child_inf
, parent_inf
);
593 parent_pspace
= parent_inf
->pspace
;
595 /* If we're vforking, we want to hold on to the parent until the
596 child exits or execs. At child exec or exit time we can
597 remove the old breakpoints from the parent and detach or
598 resume debugging it. Otherwise, detach the parent now; we'll
599 want to reuse it's program/address spaces, but we can't set
600 them to the child before removing breakpoints from the
601 parent, otherwise, the breakpoints module could decide to
602 remove breakpoints from the wrong process (since they'd be
603 assigned to the same address space). */
607 gdb_assert (child_inf
->vfork_parent
== NULL
);
608 gdb_assert (parent_inf
->vfork_child
== NULL
);
609 child_inf
->vfork_parent
= parent_inf
;
610 child_inf
->pending_detach
= 0;
611 parent_inf
->vfork_child
= child_inf
;
612 parent_inf
->pending_detach
= detach_fork
;
613 parent_inf
->waiting_for_vfork_done
= 0;
615 else if (detach_fork
)
617 if (info_verbose
|| debug_infrun
)
619 /* Ensure that we have a process ptid. */
620 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
622 target_terminal_ours_for_output ();
623 fprintf_filtered (gdb_stdlog
,
624 _("Detaching after fork from "
626 target_pid_to_str (process_ptid
));
629 target_detach (NULL
, 0);
632 /* Note that the detach above makes PARENT_INF dangling. */
634 /* Add the child thread to the appropriate lists, and switch to
635 this new thread, before cloning the program space, and
636 informing the solib layer about this new process. */
638 inferior_ptid
= child_ptid
;
639 add_thread (inferior_ptid
);
641 /* If this is a vfork child, then the address-space is shared
642 with the parent. If we detached from the parent, then we can
643 reuse the parent's program/address spaces. */
644 if (has_vforked
|| detach_fork
)
646 child_inf
->pspace
= parent_pspace
;
647 child_inf
->aspace
= child_inf
->pspace
->aspace
;
651 child_inf
->aspace
= new_address_space ();
652 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
653 child_inf
->removable
= 1;
654 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
655 set_current_program_space (child_inf
->pspace
);
656 clone_program_space (child_inf
->pspace
, parent_pspace
);
658 /* Let the shared library layer (e.g., solib-svr4) learn
659 about this new process, relocate the cloned exec, pull in
660 shared libraries, and install the solib event breakpoint.
661 If a "cloned-VM" event was propagated better throughout
662 the core, this wouldn't be required. */
663 solib_create_inferior_hook (0);
667 return target_follow_fork (follow_child
, detach_fork
);
670 /* Tell the target to follow the fork we're stopped at. Returns true
671 if the inferior should be resumed; false, if the target for some
672 reason decided it's best not to resume. */
677 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
678 int should_resume
= 1;
679 struct thread_info
*tp
;
681 /* Copy user stepping state to the new inferior thread. FIXME: the
682 followed fork child thread should have a copy of most of the
683 parent thread structure's run control related fields, not just these.
684 Initialized to avoid "may be used uninitialized" warnings from gcc. */
685 struct breakpoint
*step_resume_breakpoint
= NULL
;
686 struct breakpoint
*exception_resume_breakpoint
= NULL
;
687 CORE_ADDR step_range_start
= 0;
688 CORE_ADDR step_range_end
= 0;
689 struct frame_id step_frame_id
= { 0 };
690 struct interp
*command_interp
= NULL
;
695 struct target_waitstatus wait_status
;
697 /* Get the last target status returned by target_wait(). */
698 get_last_target_status (&wait_ptid
, &wait_status
);
700 /* If not stopped at a fork event, then there's nothing else to
702 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
703 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
706 /* Check if we switched over from WAIT_PTID, since the event was
708 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
709 && !ptid_equal (inferior_ptid
, wait_ptid
))
711 /* We did. Switch back to WAIT_PTID thread, to tell the
712 target to follow it (in either direction). We'll
713 afterwards refuse to resume, and inform the user what
715 switch_to_thread (wait_ptid
);
720 tp
= inferior_thread ();
722 /* If there were any forks/vforks that were caught and are now to be
723 followed, then do so now. */
724 switch (tp
->pending_follow
.kind
)
726 case TARGET_WAITKIND_FORKED
:
727 case TARGET_WAITKIND_VFORKED
:
729 ptid_t parent
, child
;
731 /* If the user did a next/step, etc, over a fork call,
732 preserve the stepping state in the fork child. */
733 if (follow_child
&& should_resume
)
735 step_resume_breakpoint
= clone_momentary_breakpoint
736 (tp
->control
.step_resume_breakpoint
);
737 step_range_start
= tp
->control
.step_range_start
;
738 step_range_end
= tp
->control
.step_range_end
;
739 step_frame_id
= tp
->control
.step_frame_id
;
740 exception_resume_breakpoint
741 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
742 command_interp
= tp
->control
.command_interp
;
744 /* For now, delete the parent's sr breakpoint, otherwise,
745 parent/child sr breakpoints are considered duplicates,
746 and the child version will not be installed. Remove
747 this when the breakpoints module becomes aware of
748 inferiors and address spaces. */
749 delete_step_resume_breakpoint (tp
);
750 tp
->control
.step_range_start
= 0;
751 tp
->control
.step_range_end
= 0;
752 tp
->control
.step_frame_id
= null_frame_id
;
753 delete_exception_resume_breakpoint (tp
);
754 tp
->control
.command_interp
= NULL
;
757 parent
= inferior_ptid
;
758 child
= tp
->pending_follow
.value
.related_pid
;
760 /* Set up inferior(s) as specified by the caller, and tell the
761 target to do whatever is necessary to follow either parent
763 if (follow_fork_inferior (follow_child
, detach_fork
))
765 /* Target refused to follow, or there's some other reason
766 we shouldn't resume. */
771 /* This pending follow fork event is now handled, one way
772 or another. The previous selected thread may be gone
773 from the lists by now, but if it is still around, need
774 to clear the pending follow request. */
775 tp
= find_thread_ptid (parent
);
777 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
779 /* This makes sure we don't try to apply the "Switched
780 over from WAIT_PID" logic above. */
781 nullify_last_target_wait_ptid ();
783 /* If we followed the child, switch to it... */
786 switch_to_thread (child
);
788 /* ... and preserve the stepping state, in case the
789 user was stepping over the fork call. */
792 tp
= inferior_thread ();
793 tp
->control
.step_resume_breakpoint
794 = step_resume_breakpoint
;
795 tp
->control
.step_range_start
= step_range_start
;
796 tp
->control
.step_range_end
= step_range_end
;
797 tp
->control
.step_frame_id
= step_frame_id
;
798 tp
->control
.exception_resume_breakpoint
799 = exception_resume_breakpoint
;
800 tp
->control
.command_interp
= command_interp
;
804 /* If we get here, it was because we're trying to
805 resume from a fork catchpoint, but, the user
806 has switched threads away from the thread that
807 forked. In that case, the resume command
808 issued is most likely not applicable to the
809 child, so just warn, and refuse to resume. */
810 warning (_("Not resuming: switched threads "
811 "before following fork child."));
814 /* Reset breakpoints in the child as appropriate. */
815 follow_inferior_reset_breakpoints ();
818 switch_to_thread (parent
);
822 case TARGET_WAITKIND_SPURIOUS
:
823 /* Nothing to follow. */
826 internal_error (__FILE__
, __LINE__
,
827 "Unexpected pending_follow.kind %d\n",
828 tp
->pending_follow
.kind
);
832 return should_resume
;
836 follow_inferior_reset_breakpoints (void)
838 struct thread_info
*tp
= inferior_thread ();
840 /* Was there a step_resume breakpoint? (There was if the user
841 did a "next" at the fork() call.) If so, explicitly reset its
842 thread number. Cloned step_resume breakpoints are disabled on
843 creation, so enable it here now that it is associated with the
846 step_resumes are a form of bp that are made to be per-thread.
847 Since we created the step_resume bp when the parent process
848 was being debugged, and now are switching to the child process,
849 from the breakpoint package's viewpoint, that's a switch of
850 "threads". We must update the bp's notion of which thread
851 it is for, or it'll be ignored when it triggers. */
853 if (tp
->control
.step_resume_breakpoint
)
855 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
856 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
859 /* Treat exception_resume breakpoints like step_resume breakpoints. */
860 if (tp
->control
.exception_resume_breakpoint
)
862 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
863 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
866 /* Reinsert all breakpoints in the child. The user may have set
867 breakpoints after catching the fork, in which case those
868 were never set in the child, but only in the parent. This makes
869 sure the inserted breakpoints match the breakpoint list. */
871 breakpoint_re_set ();
872 insert_breakpoints ();
875 /* The child has exited or execed: resume threads of the parent the
876 user wanted to be executing. */
879 proceed_after_vfork_done (struct thread_info
*thread
,
882 int pid
= * (int *) arg
;
884 if (ptid_get_pid (thread
->ptid
) == pid
885 && is_running (thread
->ptid
)
886 && !is_executing (thread
->ptid
)
887 && !thread
->stop_requested
888 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
891 fprintf_unfiltered (gdb_stdlog
,
892 "infrun: resuming vfork parent thread %s\n",
893 target_pid_to_str (thread
->ptid
));
895 switch_to_thread (thread
->ptid
);
896 clear_proceed_status (0);
897 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
903 /* Called whenever we notice an exec or exit event, to handle
904 detaching or resuming a vfork parent. */
907 handle_vfork_child_exec_or_exit (int exec
)
909 struct inferior
*inf
= current_inferior ();
911 if (inf
->vfork_parent
)
913 int resume_parent
= -1;
915 /* This exec or exit marks the end of the shared memory region
916 between the parent and the child. If the user wanted to
917 detach from the parent, now is the time. */
919 if (inf
->vfork_parent
->pending_detach
)
921 struct thread_info
*tp
;
922 struct cleanup
*old_chain
;
923 struct program_space
*pspace
;
924 struct address_space
*aspace
;
926 /* follow-fork child, detach-on-fork on. */
928 inf
->vfork_parent
->pending_detach
= 0;
932 /* If we're handling a child exit, then inferior_ptid
933 points at the inferior's pid, not to a thread. */
934 old_chain
= save_inferior_ptid ();
935 save_current_program_space ();
936 save_current_inferior ();
939 old_chain
= save_current_space_and_thread ();
941 /* We're letting loose of the parent. */
942 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
943 switch_to_thread (tp
->ptid
);
945 /* We're about to detach from the parent, which implicitly
946 removes breakpoints from its address space. There's a
947 catch here: we want to reuse the spaces for the child,
948 but, parent/child are still sharing the pspace at this
949 point, although the exec in reality makes the kernel give
950 the child a fresh set of new pages. The problem here is
951 that the breakpoints module being unaware of this, would
952 likely chose the child process to write to the parent
953 address space. Swapping the child temporarily away from
954 the spaces has the desired effect. Yes, this is "sort
957 pspace
= inf
->pspace
;
958 aspace
= inf
->aspace
;
962 if (debug_infrun
|| info_verbose
)
964 target_terminal_ours_for_output ();
968 fprintf_filtered (gdb_stdlog
,
969 _("Detaching vfork parent process "
970 "%d after child exec.\n"),
971 inf
->vfork_parent
->pid
);
975 fprintf_filtered (gdb_stdlog
,
976 _("Detaching vfork parent process "
977 "%d after child exit.\n"),
978 inf
->vfork_parent
->pid
);
982 target_detach (NULL
, 0);
985 inf
->pspace
= pspace
;
986 inf
->aspace
= aspace
;
988 do_cleanups (old_chain
);
992 /* We're staying attached to the parent, so, really give the
993 child a new address space. */
994 inf
->pspace
= add_program_space (maybe_new_address_space ());
995 inf
->aspace
= inf
->pspace
->aspace
;
997 set_current_program_space (inf
->pspace
);
999 resume_parent
= inf
->vfork_parent
->pid
;
1001 /* Break the bonds. */
1002 inf
->vfork_parent
->vfork_child
= NULL
;
1006 struct cleanup
*old_chain
;
1007 struct program_space
*pspace
;
1009 /* If this is a vfork child exiting, then the pspace and
1010 aspaces were shared with the parent. Since we're
1011 reporting the process exit, we'll be mourning all that is
1012 found in the address space, and switching to null_ptid,
1013 preparing to start a new inferior. But, since we don't
1014 want to clobber the parent's address/program spaces, we
1015 go ahead and create a new one for this exiting
1018 /* Switch to null_ptid, so that clone_program_space doesn't want
1019 to read the selected frame of a dead process. */
1020 old_chain
= save_inferior_ptid ();
1021 inferior_ptid
= null_ptid
;
1023 /* This inferior is dead, so avoid giving the breakpoints
1024 module the option to write through to it (cloning a
1025 program space resets breakpoints). */
1028 pspace
= add_program_space (maybe_new_address_space ());
1029 set_current_program_space (pspace
);
1031 inf
->symfile_flags
= SYMFILE_NO_READ
;
1032 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1033 inf
->pspace
= pspace
;
1034 inf
->aspace
= pspace
->aspace
;
1036 /* Put back inferior_ptid. We'll continue mourning this
1038 do_cleanups (old_chain
);
1040 resume_parent
= inf
->vfork_parent
->pid
;
1041 /* Break the bonds. */
1042 inf
->vfork_parent
->vfork_child
= NULL
;
1045 inf
->vfork_parent
= NULL
;
1047 gdb_assert (current_program_space
== inf
->pspace
);
1049 if (non_stop
&& resume_parent
!= -1)
1051 /* If the user wanted the parent to be running, let it go
1053 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1056 fprintf_unfiltered (gdb_stdlog
,
1057 "infrun: resuming vfork parent process %d\n",
1060 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1062 do_cleanups (old_chain
);
1067 /* Enum strings for "set|show follow-exec-mode". */
1069 static const char follow_exec_mode_new
[] = "new";
1070 static const char follow_exec_mode_same
[] = "same";
1071 static const char *const follow_exec_mode_names
[] =
1073 follow_exec_mode_new
,
1074 follow_exec_mode_same
,
1078 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1080 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1081 struct cmd_list_element
*c
, const char *value
)
1083 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1086 /* EXECD_PATHNAME is assumed to be non-NULL. */
1089 follow_exec (ptid_t ptid
, char *execd_pathname
)
1091 struct thread_info
*th
, *tmp
;
1092 struct inferior
*inf
= current_inferior ();
1093 int pid
= ptid_get_pid (ptid
);
1094 ptid_t process_ptid
;
1096 /* This is an exec event that we actually wish to pay attention to.
1097 Refresh our symbol table to the newly exec'd program, remove any
1098 momentary bp's, etc.
1100 If there are breakpoints, they aren't really inserted now,
1101 since the exec() transformed our inferior into a fresh set
1104 We want to preserve symbolic breakpoints on the list, since
1105 we have hopes that they can be reset after the new a.out's
1106 symbol table is read.
1108 However, any "raw" breakpoints must be removed from the list
1109 (e.g., the solib bp's), since their address is probably invalid
1112 And, we DON'T want to call delete_breakpoints() here, since
1113 that may write the bp's "shadow contents" (the instruction
1114 value that was overwritten witha TRAP instruction). Since
1115 we now have a new a.out, those shadow contents aren't valid. */
1117 mark_breakpoints_out ();
1119 /* The target reports the exec event to the main thread, even if
1120 some other thread does the exec, and even if the main thread was
1121 stopped or already gone. We may still have non-leader threads of
1122 the process on our list. E.g., on targets that don't have thread
1123 exit events (like remote); or on native Linux in non-stop mode if
1124 there were only two threads in the inferior and the non-leader
1125 one is the one that execs (and nothing forces an update of the
1126 thread list up to here). When debugging remotely, it's best to
1127 avoid extra traffic, when possible, so avoid syncing the thread
1128 list with the target, and instead go ahead and delete all threads
1129 of the process but one that reported the event. Note this must
1130 be done before calling update_breakpoints_after_exec, as
1131 otherwise clearing the threads' resources would reference stale
1132 thread breakpoints -- it may have been one of these threads that
1133 stepped across the exec. We could just clear their stepping
1134 states, but as long as we're iterating, might as well delete
1135 them. Deleting them now rather than at the next user-visible
1136 stop provides a nicer sequence of events for user and MI
1138 ALL_THREADS_SAFE (th
, tmp
)
1139 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1140 delete_thread (th
->ptid
);
1142 /* We also need to clear any left over stale state for the
1143 leader/event thread. E.g., if there was any step-resume
1144 breakpoint or similar, it's gone now. We cannot truly
1145 step-to-next statement through an exec(). */
1146 th
= inferior_thread ();
1147 th
->control
.step_resume_breakpoint
= NULL
;
1148 th
->control
.exception_resume_breakpoint
= NULL
;
1149 th
->control
.single_step_breakpoints
= NULL
;
1150 th
->control
.step_range_start
= 0;
1151 th
->control
.step_range_end
= 0;
1153 /* The user may have had the main thread held stopped in the
1154 previous image (e.g., schedlock on, or non-stop). Release
1156 th
->stop_requested
= 0;
1158 update_breakpoints_after_exec ();
1160 /* What is this a.out's name? */
1161 process_ptid
= pid_to_ptid (pid
);
1162 printf_unfiltered (_("%s is executing new program: %s\n"),
1163 target_pid_to_str (process_ptid
),
1166 /* We've followed the inferior through an exec. Therefore, the
1167 inferior has essentially been killed & reborn. */
1169 gdb_flush (gdb_stdout
);
1171 breakpoint_init_inferior (inf_execd
);
1173 if (*gdb_sysroot
!= '\0')
1175 char *name
= exec_file_find (execd_pathname
, NULL
);
1177 execd_pathname
= (char *) alloca (strlen (name
) + 1);
1178 strcpy (execd_pathname
, name
);
1182 /* Reset the shared library package. This ensures that we get a
1183 shlib event when the child reaches "_start", at which point the
1184 dld will have had a chance to initialize the child. */
1185 /* Also, loading a symbol file below may trigger symbol lookups, and
1186 we don't want those to be satisfied by the libraries of the
1187 previous incarnation of this process. */
1188 no_shared_libraries (NULL
, 0);
1190 if (follow_exec_mode_string
== follow_exec_mode_new
)
1192 /* The user wants to keep the old inferior and program spaces
1193 around. Create a new fresh one, and switch to it. */
1195 /* Do exit processing for the original inferior before adding
1196 the new inferior so we don't have two active inferiors with
1197 the same ptid, which can confuse find_inferior_ptid. */
1198 exit_inferior_num_silent (current_inferior ()->num
);
1200 inf
= add_inferior_with_spaces ();
1202 target_follow_exec (inf
, execd_pathname
);
1204 set_current_inferior (inf
);
1205 set_current_program_space (inf
->pspace
);
1210 /* The old description may no longer be fit for the new image.
1211 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1212 old description; we'll read a new one below. No need to do
1213 this on "follow-exec-mode new", as the old inferior stays
1214 around (its description is later cleared/refetched on
1216 target_clear_description ();
1219 gdb_assert (current_program_space
== inf
->pspace
);
1221 /* That a.out is now the one to use. */
1222 exec_file_attach (execd_pathname
, 0);
1224 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1225 (Position Independent Executable) main symbol file will get applied by
1226 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1227 the breakpoints with the zero displacement. */
1229 symbol_file_add (execd_pathname
,
1231 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
1234 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
1235 set_initial_language ();
1237 /* If the target can specify a description, read it. Must do this
1238 after flipping to the new executable (because the target supplied
1239 description must be compatible with the executable's
1240 architecture, and the old executable may e.g., be 32-bit, while
1241 the new one 64-bit), and before anything involving memory or
1243 target_find_description ();
1245 solib_create_inferior_hook (0);
1247 jit_inferior_created_hook ();
1249 breakpoint_re_set ();
1251 /* Reinsert all breakpoints. (Those which were symbolic have
1252 been reset to the proper address in the new a.out, thanks
1253 to symbol_file_command...). */
1254 insert_breakpoints ();
1256 /* The next resume of this inferior should bring it to the shlib
1257 startup breakpoints. (If the user had also set bp's on
1258 "main" from the old (parent) process, then they'll auto-
1259 matically get reset there in the new process.). */
1262 /* The queue of threads that need to do a step-over operation to get
1263 past e.g., a breakpoint. What technique is used to step over the
1264 breakpoint/watchpoint does not matter -- all threads end up in the
1265 same queue, to maintain rough temporal order of execution, in order
1266 to avoid starvation, otherwise, we could e.g., find ourselves
1267 constantly stepping the same couple threads past their breakpoints
1268 over and over, if the single-step finish fast enough. */
1269 struct thread_info
*step_over_queue_head
;
1271 /* Bit flags indicating what the thread needs to step over. */
1273 enum step_over_what_flag
1275 /* Step over a breakpoint. */
1276 STEP_OVER_BREAKPOINT
= 1,
1278 /* Step past a non-continuable watchpoint, in order to let the
1279 instruction execute so we can evaluate the watchpoint
1281 STEP_OVER_WATCHPOINT
= 2
1283 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1285 /* Info about an instruction that is being stepped over. */
1287 struct step_over_info
1289 /* If we're stepping past a breakpoint, this is the address space
1290 and address of the instruction the breakpoint is set at. We'll
1291 skip inserting all breakpoints here. Valid iff ASPACE is
1293 struct address_space
*aspace
;
1296 /* The instruction being stepped over triggers a nonsteppable
1297 watchpoint. If true, we'll skip inserting watchpoints. */
1298 int nonsteppable_watchpoint_p
;
1301 /* The step-over info of the location that is being stepped over.
1303 Note that with async/breakpoint always-inserted mode, a user might
1304 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1305 being stepped over. As setting a new breakpoint inserts all
1306 breakpoints, we need to make sure the breakpoint being stepped over
1307 isn't inserted then. We do that by only clearing the step-over
1308 info when the step-over is actually finished (or aborted).
1310 Presently GDB can only step over one breakpoint at any given time.
1311 Given threads that can't run code in the same address space as the
1312 breakpoint's can't really miss the breakpoint, GDB could be taught
1313 to step-over at most one breakpoint per address space (so this info
1314 could move to the address space object if/when GDB is extended).
1315 The set of breakpoints being stepped over will normally be much
1316 smaller than the set of all breakpoints, so a flag in the
1317 breakpoint location structure would be wasteful. A separate list
1318 also saves complexity and run-time, as otherwise we'd have to go
1319 through all breakpoint locations clearing their flag whenever we
1320 start a new sequence. Similar considerations weigh against storing
1321 this info in the thread object. Plus, not all step overs actually
1322 have breakpoint locations -- e.g., stepping past a single-step
1323 breakpoint, or stepping to complete a non-continuable
1325 static struct step_over_info step_over_info
;
1327 /* Record the address of the breakpoint/instruction we're currently
1331 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1332 int nonsteppable_watchpoint_p
)
1334 step_over_info
.aspace
= aspace
;
1335 step_over_info
.address
= address
;
1336 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1339 /* Called when we're not longer stepping over a breakpoint / an
1340 instruction, so all breakpoints are free to be (re)inserted. */
1343 clear_step_over_info (void)
1346 fprintf_unfiltered (gdb_stdlog
,
1347 "infrun: clear_step_over_info\n");
1348 step_over_info
.aspace
= NULL
;
1349 step_over_info
.address
= 0;
1350 step_over_info
.nonsteppable_watchpoint_p
= 0;
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 stepping_past_nonsteppable_watchpoint (void)
1370 return step_over_info
.nonsteppable_watchpoint_p
;
1373 /* Returns true if step-over info is valid. */
1376 step_over_info_valid_p (void)
1378 return (step_over_info
.aspace
!= NULL
1379 || stepping_past_nonsteppable_watchpoint ());
1383 /* Displaced stepping. */
1385 /* In non-stop debugging mode, we must take special care to manage
1386 breakpoints properly; in particular, the traditional strategy for
1387 stepping a thread past a breakpoint it has hit is unsuitable.
1388 'Displaced stepping' is a tactic for stepping one thread past a
1389 breakpoint it has hit while ensuring that other threads running
1390 concurrently will hit the breakpoint as they should.
1392 The traditional way to step a thread T off a breakpoint in a
1393 multi-threaded program in all-stop mode is as follows:
1395 a0) Initially, all threads are stopped, and breakpoints are not
1397 a1) We single-step T, leaving breakpoints uninserted.
1398 a2) We insert breakpoints, and resume all threads.
1400 In non-stop debugging, however, this strategy is unsuitable: we
1401 don't want to have to stop all threads in the system in order to
1402 continue or step T past a breakpoint. Instead, we use displaced
1405 n0) Initially, T is stopped, other threads are running, and
1406 breakpoints are inserted.
1407 n1) We copy the instruction "under" the breakpoint to a separate
1408 location, outside the main code stream, making any adjustments
1409 to the instruction, register, and memory state as directed by
1411 n2) We single-step T over the instruction at its new location.
1412 n3) We adjust the resulting register and memory state as directed
1413 by T's architecture. This includes resetting T's PC to point
1414 back into the main instruction stream.
1417 This approach depends on the following gdbarch methods:
1419 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1420 indicate where to copy the instruction, and how much space must
1421 be reserved there. We use these in step n1.
1423 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1424 address, and makes any necessary adjustments to the instruction,
1425 register contents, and memory. We use this in step n1.
1427 - gdbarch_displaced_step_fixup adjusts registers and memory after
1428 we have successfuly single-stepped the instruction, to yield the
1429 same effect the instruction would have had if we had executed it
1430 at its original address. We use this in step n3.
1432 - gdbarch_displaced_step_free_closure provides cleanup.
1434 The gdbarch_displaced_step_copy_insn and
1435 gdbarch_displaced_step_fixup functions must be written so that
1436 copying an instruction with gdbarch_displaced_step_copy_insn,
1437 single-stepping across the copied instruction, and then applying
1438 gdbarch_displaced_insn_fixup should have the same effects on the
1439 thread's memory and registers as stepping the instruction in place
1440 would have. Exactly which responsibilities fall to the copy and
1441 which fall to the fixup is up to the author of those functions.
1443 See the comments in gdbarch.sh for details.
1445 Note that displaced stepping and software single-step cannot
1446 currently be used in combination, although with some care I think
1447 they could be made to. Software single-step works by placing
1448 breakpoints on all possible subsequent instructions; if the
1449 displaced instruction is a PC-relative jump, those breakpoints
1450 could fall in very strange places --- on pages that aren't
1451 executable, or at addresses that are not proper instruction
1452 boundaries. (We do generally let other threads run while we wait
1453 to hit the software single-step breakpoint, and they might
1454 encounter such a corrupted instruction.) One way to work around
1455 this would be to have gdbarch_displaced_step_copy_insn fully
1456 simulate the effect of PC-relative instructions (and return NULL)
1457 on architectures that use software single-stepping.
1459 In non-stop mode, we can have independent and simultaneous step
1460 requests, so more than one thread may need to simultaneously step
1461 over a breakpoint. The current implementation assumes there is
1462 only one scratch space per process. In this case, we have to
1463 serialize access to the scratch space. If thread A wants to step
1464 over a breakpoint, but we are currently waiting for some other
1465 thread to complete a displaced step, we leave thread A stopped and
1466 place it in the displaced_step_request_queue. Whenever a displaced
1467 step finishes, we pick the next thread in the queue and start a new
1468 displaced step operation on it. See displaced_step_prepare and
1469 displaced_step_fixup for details. */
1471 /* Per-inferior displaced stepping state. */
1472 struct displaced_step_inferior_state
1474 /* Pointer to next in linked list. */
1475 struct displaced_step_inferior_state
*next
;
1477 /* The process this displaced step state refers to. */
1480 /* True if preparing a displaced step ever failed. If so, we won't
1481 try displaced stepping for this inferior again. */
1484 /* If this is not null_ptid, this is the thread carrying out a
1485 displaced single-step in process PID. This thread's state will
1486 require fixing up once it has completed its step. */
1489 /* The architecture the thread had when we stepped it. */
1490 struct gdbarch
*step_gdbarch
;
1492 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1493 for post-step cleanup. */
1494 struct displaced_step_closure
*step_closure
;
1496 /* The address of the original instruction, and the copy we
1498 CORE_ADDR step_original
, step_copy
;
1500 /* Saved contents of copy area. */
1501 gdb_byte
*step_saved_copy
;
1504 /* The list of states of processes involved in displaced stepping
1506 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1508 /* Get the displaced stepping state of process PID. */
1510 static struct displaced_step_inferior_state
*
1511 get_displaced_stepping_state (int pid
)
1513 struct displaced_step_inferior_state
*state
;
1515 for (state
= displaced_step_inferior_states
;
1517 state
= state
->next
)
1518 if (state
->pid
== pid
)
1524 /* Returns true if any inferior has a thread doing a displaced
1528 displaced_step_in_progress_any_inferior (void)
1530 struct displaced_step_inferior_state
*state
;
1532 for (state
= displaced_step_inferior_states
;
1534 state
= state
->next
)
1535 if (!ptid_equal (state
->step_ptid
, null_ptid
))
1541 /* Return true if thread represented by PTID is doing a displaced
1545 displaced_step_in_progress_thread (ptid_t ptid
)
1547 struct displaced_step_inferior_state
*displaced
;
1549 gdb_assert (!ptid_equal (ptid
, null_ptid
));
1551 displaced
= get_displaced_stepping_state (ptid_get_pid (ptid
));
1553 return (displaced
!= NULL
&& ptid_equal (displaced
->step_ptid
, ptid
));
1556 /* Return true if process PID has a thread doing a displaced step. */
1559 displaced_step_in_progress (int pid
)
1561 struct displaced_step_inferior_state
*displaced
;
1563 displaced
= get_displaced_stepping_state (pid
);
1564 if (displaced
!= NULL
&& !ptid_equal (displaced
->step_ptid
, null_ptid
))
1570 /* Add a new displaced stepping state for process PID to the displaced
1571 stepping state list, or return a pointer to an already existing
1572 entry, if it already exists. Never returns NULL. */
1574 static struct displaced_step_inferior_state
*
1575 add_displaced_stepping_state (int pid
)
1577 struct displaced_step_inferior_state
*state
;
1579 for (state
= displaced_step_inferior_states
;
1581 state
= state
->next
)
1582 if (state
->pid
== pid
)
1585 state
= XCNEW (struct displaced_step_inferior_state
);
1587 state
->next
= displaced_step_inferior_states
;
1588 displaced_step_inferior_states
= state
;
1593 /* If inferior is in displaced stepping, and ADDR equals to starting address
1594 of copy area, return corresponding displaced_step_closure. Otherwise,
1597 struct displaced_step_closure
*
1598 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1600 struct displaced_step_inferior_state
*displaced
1601 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1603 /* If checking the mode of displaced instruction in copy area. */
1604 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1605 && (displaced
->step_copy
== addr
))
1606 return displaced
->step_closure
;
1611 /* Remove the displaced stepping state of process PID. */
1614 remove_displaced_stepping_state (int pid
)
1616 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1618 gdb_assert (pid
!= 0);
1620 it
= displaced_step_inferior_states
;
1621 prev_next_p
= &displaced_step_inferior_states
;
1626 *prev_next_p
= it
->next
;
1631 prev_next_p
= &it
->next
;
1637 infrun_inferior_exit (struct inferior
*inf
)
1639 remove_displaced_stepping_state (inf
->pid
);
1642 /* If ON, and the architecture supports it, GDB will use displaced
1643 stepping to step over breakpoints. If OFF, or if the architecture
1644 doesn't support it, GDB will instead use the traditional
1645 hold-and-step approach. If AUTO (which is the default), GDB will
1646 decide which technique to use to step over breakpoints depending on
1647 which of all-stop or non-stop mode is active --- displaced stepping
1648 in non-stop mode; hold-and-step in all-stop mode. */
1650 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1653 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1654 struct cmd_list_element
*c
,
1657 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1658 fprintf_filtered (file
,
1659 _("Debugger's willingness to use displaced stepping "
1660 "to step over breakpoints is %s (currently %s).\n"),
1661 value
, target_is_non_stop_p () ? "on" : "off");
1663 fprintf_filtered (file
,
1664 _("Debugger's willingness to use displaced stepping "
1665 "to step over breakpoints is %s.\n"), value
);
1668 /* Return non-zero if displaced stepping can/should be used to step
1669 over breakpoints of thread TP. */
1672 use_displaced_stepping (struct thread_info
*tp
)
1674 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
1675 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1676 struct displaced_step_inferior_state
*displaced_state
;
1678 displaced_state
= get_displaced_stepping_state (ptid_get_pid (tp
->ptid
));
1680 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1681 && target_is_non_stop_p ())
1682 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1683 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1684 && find_record_target () == NULL
1685 && (displaced_state
== NULL
1686 || !displaced_state
->failed_before
));
1689 /* Clean out any stray displaced stepping state. */
1691 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1693 /* Indicate that there is no cleanup pending. */
1694 displaced
->step_ptid
= null_ptid
;
1696 if (displaced
->step_closure
)
1698 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1699 displaced
->step_closure
);
1700 displaced
->step_closure
= NULL
;
1705 displaced_step_clear_cleanup (void *arg
)
1707 struct displaced_step_inferior_state
*state
1708 = (struct displaced_step_inferior_state
*) arg
;
1710 displaced_step_clear (state
);
1713 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1715 displaced_step_dump_bytes (struct ui_file
*file
,
1716 const gdb_byte
*buf
,
1721 for (i
= 0; i
< len
; i
++)
1722 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1723 fputs_unfiltered ("\n", file
);
1726 /* Prepare to single-step, using displaced stepping.
1728 Note that we cannot use displaced stepping when we have a signal to
1729 deliver. If we have a signal to deliver and an instruction to step
1730 over, then after the step, there will be no indication from the
1731 target whether the thread entered a signal handler or ignored the
1732 signal and stepped over the instruction successfully --- both cases
1733 result in a simple SIGTRAP. In the first case we mustn't do a
1734 fixup, and in the second case we must --- but we can't tell which.
1735 Comments in the code for 'random signals' in handle_inferior_event
1736 explain how we handle this case instead.
1738 Returns 1 if preparing was successful -- this thread is going to be
1739 stepped now; 0 if displaced stepping this thread got queued; or -1
1740 if this instruction can't be displaced stepped. */
1743 displaced_step_prepare_throw (ptid_t ptid
)
1745 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1746 struct thread_info
*tp
= find_thread_ptid (ptid
);
1747 struct regcache
*regcache
= get_thread_regcache (ptid
);
1748 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1749 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1750 CORE_ADDR original
, copy
;
1752 struct displaced_step_closure
*closure
;
1753 struct displaced_step_inferior_state
*displaced
;
1756 /* We should never reach this function if the architecture does not
1757 support displaced stepping. */
1758 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1760 /* Nor if the thread isn't meant to step over a breakpoint. */
1761 gdb_assert (tp
->control
.trap_expected
);
1763 /* Disable range stepping while executing in the scratch pad. We
1764 want a single-step even if executing the displaced instruction in
1765 the scratch buffer lands within the stepping range (e.g., a
1767 tp
->control
.may_range_step
= 0;
1769 /* We have to displaced step one thread at a time, as we only have
1770 access to a single scratch space per inferior. */
1772 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1774 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1776 /* Already waiting for a displaced step to finish. Defer this
1777 request and place in queue. */
1779 if (debug_displaced
)
1780 fprintf_unfiltered (gdb_stdlog
,
1781 "displaced: deferring step of %s\n",
1782 target_pid_to_str (ptid
));
1784 thread_step_over_chain_enqueue (tp
);
1789 if (debug_displaced
)
1790 fprintf_unfiltered (gdb_stdlog
,
1791 "displaced: stepping %s now\n",
1792 target_pid_to_str (ptid
));
1795 displaced_step_clear (displaced
);
1797 old_cleanups
= save_inferior_ptid ();
1798 inferior_ptid
= ptid
;
1800 original
= regcache_read_pc (regcache
);
1802 copy
= gdbarch_displaced_step_location (gdbarch
);
1803 len
= gdbarch_max_insn_length (gdbarch
);
1805 if (breakpoint_in_range_p (aspace
, copy
, len
))
1807 /* There's a breakpoint set in the scratch pad location range
1808 (which is usually around the entry point). We'd either
1809 install it before resuming, which would overwrite/corrupt the
1810 scratch pad, or if it was already inserted, this displaced
1811 step would overwrite it. The latter is OK in the sense that
1812 we already assume that no thread is going to execute the code
1813 in the scratch pad range (after initial startup) anyway, but
1814 the former is unacceptable. Simply punt and fallback to
1815 stepping over this breakpoint in-line. */
1816 if (debug_displaced
)
1818 fprintf_unfiltered (gdb_stdlog
,
1819 "displaced: breakpoint set in scratch pad. "
1820 "Stepping over breakpoint in-line instead.\n");
1823 do_cleanups (old_cleanups
);
1827 /* Save the original contents of the copy area. */
1828 displaced
->step_saved_copy
= (gdb_byte
*) xmalloc (len
);
1829 ignore_cleanups
= make_cleanup (free_current_contents
,
1830 &displaced
->step_saved_copy
);
1831 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1833 throw_error (MEMORY_ERROR
,
1834 _("Error accessing memory address %s (%s) for "
1835 "displaced-stepping scratch space."),
1836 paddress (gdbarch
, copy
), safe_strerror (status
));
1837 if (debug_displaced
)
1839 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1840 paddress (gdbarch
, copy
));
1841 displaced_step_dump_bytes (gdb_stdlog
,
1842 displaced
->step_saved_copy
,
1846 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1847 original
, copy
, regcache
);
1848 if (closure
== NULL
)
1850 /* The architecture doesn't know how or want to displaced step
1851 this instruction or instruction sequence. Fallback to
1852 stepping over the breakpoint in-line. */
1853 do_cleanups (old_cleanups
);
1857 /* Save the information we need to fix things up if the step
1859 displaced
->step_ptid
= ptid
;
1860 displaced
->step_gdbarch
= gdbarch
;
1861 displaced
->step_closure
= closure
;
1862 displaced
->step_original
= original
;
1863 displaced
->step_copy
= copy
;
1865 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1867 /* Resume execution at the copy. */
1868 regcache_write_pc (regcache
, copy
);
1870 discard_cleanups (ignore_cleanups
);
1872 do_cleanups (old_cleanups
);
1874 if (debug_displaced
)
1875 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1876 paddress (gdbarch
, copy
));
1881 /* Wrapper for displaced_step_prepare_throw that disabled further
1882 attempts at displaced stepping if we get a memory error. */
1885 displaced_step_prepare (ptid_t ptid
)
1891 prepared
= displaced_step_prepare_throw (ptid
);
1893 CATCH (ex
, RETURN_MASK_ERROR
)
1895 struct displaced_step_inferior_state
*displaced_state
;
1897 if (ex
.error
!= MEMORY_ERROR
)
1898 throw_exception (ex
);
1902 fprintf_unfiltered (gdb_stdlog
,
1903 "infrun: disabling displaced stepping: %s\n",
1907 /* Be verbose if "set displaced-stepping" is "on", silent if
1909 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1911 warning (_("disabling displaced stepping: %s"),
1915 /* Disable further displaced stepping attempts. */
1917 = get_displaced_stepping_state (ptid_get_pid (ptid
));
1918 displaced_state
->failed_before
= 1;
1926 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1927 const gdb_byte
*myaddr
, int len
)
1929 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1931 inferior_ptid
= ptid
;
1932 write_memory (memaddr
, myaddr
, len
);
1933 do_cleanups (ptid_cleanup
);
1936 /* Restore the contents of the copy area for thread PTID. */
1939 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1942 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1944 write_memory_ptid (ptid
, displaced
->step_copy
,
1945 displaced
->step_saved_copy
, len
);
1946 if (debug_displaced
)
1947 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1948 target_pid_to_str (ptid
),
1949 paddress (displaced
->step_gdbarch
,
1950 displaced
->step_copy
));
1953 /* If we displaced stepped an instruction successfully, adjust
1954 registers and memory to yield the same effect the instruction would
1955 have had if we had executed it at its original address, and return
1956 1. If the instruction didn't complete, relocate the PC and return
1957 -1. If the thread wasn't displaced stepping, return 0. */
1960 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1962 struct cleanup
*old_cleanups
;
1963 struct displaced_step_inferior_state
*displaced
1964 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1967 /* Was any thread of this process doing a displaced step? */
1968 if (displaced
== NULL
)
1971 /* Was this event for the pid we displaced? */
1972 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1973 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1976 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1978 displaced_step_restore (displaced
, displaced
->step_ptid
);
1980 /* Fixup may need to read memory/registers. Switch to the thread
1981 that we're fixing up. Also, target_stopped_by_watchpoint checks
1982 the current thread. */
1983 switch_to_thread (event_ptid
);
1985 /* Did the instruction complete successfully? */
1986 if (signal
== GDB_SIGNAL_TRAP
1987 && !(target_stopped_by_watchpoint ()
1988 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
1989 || target_have_steppable_watchpoint
)))
1991 /* Fix up the resulting state. */
1992 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1993 displaced
->step_closure
,
1994 displaced
->step_original
,
1995 displaced
->step_copy
,
1996 get_thread_regcache (displaced
->step_ptid
));
2001 /* Since the instruction didn't complete, all we can do is
2003 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
2004 CORE_ADDR pc
= regcache_read_pc (regcache
);
2006 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
2007 regcache_write_pc (regcache
, pc
);
2011 do_cleanups (old_cleanups
);
2013 displaced
->step_ptid
= null_ptid
;
2018 /* Data to be passed around while handling an event. This data is
2019 discarded between events. */
2020 struct execution_control_state
2023 /* The thread that got the event, if this was a thread event; NULL
2025 struct thread_info
*event_thread
;
2027 struct target_waitstatus ws
;
2028 int stop_func_filled_in
;
2029 CORE_ADDR stop_func_start
;
2030 CORE_ADDR stop_func_end
;
2031 const char *stop_func_name
;
2034 /* True if the event thread hit the single-step breakpoint of
2035 another thread. Thus the event doesn't cause a stop, the thread
2036 needs to be single-stepped past the single-step breakpoint before
2037 we can switch back to the original stepping thread. */
2038 int hit_singlestep_breakpoint
;
2041 /* Clear ECS and set it to point at TP. */
2044 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
2046 memset (ecs
, 0, sizeof (*ecs
));
2047 ecs
->event_thread
= tp
;
2048 ecs
->ptid
= tp
->ptid
;
2051 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
2052 static void prepare_to_wait (struct execution_control_state
*ecs
);
2053 static int keep_going_stepped_thread (struct thread_info
*tp
);
2054 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
2056 /* Are there any pending step-over requests? If so, run all we can
2057 now and return true. Otherwise, return false. */
2060 start_step_over (void)
2062 struct thread_info
*tp
, *next
;
2064 /* Don't start a new step-over if we already have an in-line
2065 step-over operation ongoing. */
2066 if (step_over_info_valid_p ())
2069 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
2071 struct execution_control_state ecss
;
2072 struct execution_control_state
*ecs
= &ecss
;
2073 step_over_what step_what
;
2074 int must_be_in_line
;
2076 next
= thread_step_over_chain_next (tp
);
2078 /* If this inferior already has a displaced step in process,
2079 don't start a new one. */
2080 if (displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2083 step_what
= thread_still_needs_step_over (tp
);
2084 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
2085 || ((step_what
& STEP_OVER_BREAKPOINT
)
2086 && !use_displaced_stepping (tp
)));
2088 /* We currently stop all threads of all processes to step-over
2089 in-line. If we need to start a new in-line step-over, let
2090 any pending displaced steps finish first. */
2091 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
2094 thread_step_over_chain_remove (tp
);
2096 if (step_over_queue_head
== NULL
)
2099 fprintf_unfiltered (gdb_stdlog
,
2100 "infrun: step-over queue now empty\n");
2103 if (tp
->control
.trap_expected
2107 internal_error (__FILE__
, __LINE__
,
2108 "[%s] has inconsistent state: "
2109 "trap_expected=%d, resumed=%d, executing=%d\n",
2110 target_pid_to_str (tp
->ptid
),
2111 tp
->control
.trap_expected
,
2117 fprintf_unfiltered (gdb_stdlog
,
2118 "infrun: resuming [%s] for step-over\n",
2119 target_pid_to_str (tp
->ptid
));
2121 /* keep_going_pass_signal skips the step-over if the breakpoint
2122 is no longer inserted. In all-stop, we want to keep looking
2123 for a thread that needs a step-over instead of resuming TP,
2124 because we wouldn't be able to resume anything else until the
2125 target stops again. In non-stop, the resume always resumes
2126 only TP, so it's OK to let the thread resume freely. */
2127 if (!target_is_non_stop_p () && !step_what
)
2130 switch_to_thread (tp
->ptid
);
2131 reset_ecs (ecs
, tp
);
2132 keep_going_pass_signal (ecs
);
2134 if (!ecs
->wait_some_more
)
2135 error (_("Command aborted."));
2137 gdb_assert (tp
->resumed
);
2139 /* If we started a new in-line step-over, we're done. */
2140 if (step_over_info_valid_p ())
2142 gdb_assert (tp
->control
.trap_expected
);
2146 if (!target_is_non_stop_p ())
2148 /* On all-stop, shouldn't have resumed unless we needed a
2150 gdb_assert (tp
->control
.trap_expected
2151 || tp
->step_after_step_resume_breakpoint
);
2153 /* With remote targets (at least), in all-stop, we can't
2154 issue any further remote commands until the program stops
2159 /* Either the thread no longer needed a step-over, or a new
2160 displaced stepping sequence started. Even in the latter
2161 case, continue looking. Maybe we can also start another
2162 displaced step on a thread of other process. */
2168 /* Update global variables holding ptids to hold NEW_PTID if they were
2169 holding OLD_PTID. */
2171 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2173 struct displaced_step_request
*it
;
2174 struct displaced_step_inferior_state
*displaced
;
2176 if (ptid_equal (inferior_ptid
, old_ptid
))
2177 inferior_ptid
= new_ptid
;
2179 for (displaced
= displaced_step_inferior_states
;
2181 displaced
= displaced
->next
)
2183 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
2184 displaced
->step_ptid
= new_ptid
;
2191 /* Things to clean up if we QUIT out of resume (). */
2193 resume_cleanups (void *ignore
)
2195 if (!ptid_equal (inferior_ptid
, null_ptid
))
2196 delete_single_step_breakpoints (inferior_thread ());
2201 static const char schedlock_off
[] = "off";
2202 static const char schedlock_on
[] = "on";
2203 static const char schedlock_step
[] = "step";
2204 static const char schedlock_replay
[] = "replay";
2205 static const char *const scheduler_enums
[] = {
2212 static const char *scheduler_mode
= schedlock_replay
;
2214 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2215 struct cmd_list_element
*c
, const char *value
)
2217 fprintf_filtered (file
,
2218 _("Mode for locking scheduler "
2219 "during execution is \"%s\".\n"),
2224 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
2226 if (!target_can_lock_scheduler
)
2228 scheduler_mode
= schedlock_off
;
2229 error (_("Target '%s' cannot support this command."), target_shortname
);
2233 /* True if execution commands resume all threads of all processes by
2234 default; otherwise, resume only threads of the current inferior
2236 int sched_multi
= 0;
2238 /* Try to setup for software single stepping over the specified location.
2239 Return 1 if target_resume() should use hardware single step.
2241 GDBARCH the current gdbarch.
2242 PC the location to step over. */
2245 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2249 if (execution_direction
== EXEC_FORWARD
2250 && gdbarch_software_single_step_p (gdbarch
)
2251 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
2261 user_visible_resume_ptid (int step
)
2267 /* With non-stop mode on, threads are always handled
2269 resume_ptid
= inferior_ptid
;
2271 else if ((scheduler_mode
== schedlock_on
)
2272 || (scheduler_mode
== schedlock_step
&& step
))
2274 /* User-settable 'scheduler' mode requires solo thread
2276 resume_ptid
= inferior_ptid
;
2278 else if ((scheduler_mode
== schedlock_replay
)
2279 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2281 /* User-settable 'scheduler' mode requires solo thread resume in replay
2283 resume_ptid
= inferior_ptid
;
2285 else if (!sched_multi
&& target_supports_multi_process ())
2287 /* Resume all threads of the current process (and none of other
2289 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2293 /* Resume all threads of all processes. */
2294 resume_ptid
= RESUME_ALL
;
2300 /* Return a ptid representing the set of threads that we will resume,
2301 in the perspective of the target, assuming run control handling
2302 does not require leaving some threads stopped (e.g., stepping past
2303 breakpoint). USER_STEP indicates whether we're about to start the
2304 target for a stepping command. */
2307 internal_resume_ptid (int user_step
)
2309 /* In non-stop, we always control threads individually. Note that
2310 the target may always work in non-stop mode even with "set
2311 non-stop off", in which case user_visible_resume_ptid could
2312 return a wildcard ptid. */
2313 if (target_is_non_stop_p ())
2314 return inferior_ptid
;
2316 return user_visible_resume_ptid (user_step
);
2319 /* Wrapper for target_resume, that handles infrun-specific
2323 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2325 struct thread_info
*tp
= inferior_thread ();
2327 /* Install inferior's terminal modes. */
2328 target_terminal_inferior ();
2330 /* Avoid confusing the next resume, if the next stop/resume
2331 happens to apply to another thread. */
2332 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2334 /* Advise target which signals may be handled silently.
2336 If we have removed breakpoints because we are stepping over one
2337 in-line (in any thread), we need to receive all signals to avoid
2338 accidentally skipping a breakpoint during execution of a signal
2341 Likewise if we're displaced stepping, otherwise a trap for a
2342 breakpoint in a signal handler might be confused with the
2343 displaced step finishing. We don't make the displaced_step_fixup
2344 step distinguish the cases instead, because:
2346 - a backtrace while stopped in the signal handler would show the
2347 scratch pad as frame older than the signal handler, instead of
2348 the real mainline code.
2350 - when the thread is later resumed, the signal handler would
2351 return to the scratch pad area, which would no longer be
2353 if (step_over_info_valid_p ()
2354 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2355 target_pass_signals (0, NULL
);
2357 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2359 target_resume (resume_ptid
, step
, sig
);
2362 /* Resume the inferior, but allow a QUIT. This is useful if the user
2363 wants to interrupt some lengthy single-stepping operation
2364 (for child processes, the SIGINT goes to the inferior, and so
2365 we get a SIGINT random_signal, but for remote debugging and perhaps
2366 other targets, that's not true).
2368 SIG is the signal to give the inferior (zero for none). */
2370 resume (enum gdb_signal sig
)
2372 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2373 struct regcache
*regcache
= get_current_regcache ();
2374 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2375 struct thread_info
*tp
= inferior_thread ();
2376 CORE_ADDR pc
= regcache_read_pc (regcache
);
2377 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2379 /* This represents the user's step vs continue request. When
2380 deciding whether "set scheduler-locking step" applies, it's the
2381 user's intention that counts. */
2382 const int user_step
= tp
->control
.stepping_command
;
2383 /* This represents what we'll actually request the target to do.
2384 This can decay from a step to a continue, if e.g., we need to
2385 implement single-stepping with breakpoints (software
2389 gdb_assert (!thread_is_in_step_over_chain (tp
));
2393 if (tp
->suspend
.waitstatus_pending_p
)
2399 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2400 fprintf_unfiltered (gdb_stdlog
,
2401 "infrun: resume: thread %s has pending wait status %s "
2402 "(currently_stepping=%d).\n",
2403 target_pid_to_str (tp
->ptid
), statstr
,
2404 currently_stepping (tp
));
2410 /* FIXME: What should we do if we are supposed to resume this
2411 thread with a signal? Maybe we should maintain a queue of
2412 pending signals to deliver. */
2413 if (sig
!= GDB_SIGNAL_0
)
2415 warning (_("Couldn't deliver signal %s to %s."),
2416 gdb_signal_to_name (sig
), target_pid_to_str (tp
->ptid
));
2419 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2420 discard_cleanups (old_cleanups
);
2422 if (target_can_async_p ())
2427 tp
->stepped_breakpoint
= 0;
2429 /* Depends on stepped_breakpoint. */
2430 step
= currently_stepping (tp
);
2432 if (current_inferior ()->waiting_for_vfork_done
)
2434 /* Don't try to single-step a vfork parent that is waiting for
2435 the child to get out of the shared memory region (by exec'ing
2436 or exiting). This is particularly important on software
2437 single-step archs, as the child process would trip on the
2438 software single step breakpoint inserted for the parent
2439 process. Since the parent will not actually execute any
2440 instruction until the child is out of the shared region (such
2441 are vfork's semantics), it is safe to simply continue it.
2442 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2443 the parent, and tell it to `keep_going', which automatically
2444 re-sets it stepping. */
2446 fprintf_unfiltered (gdb_stdlog
,
2447 "infrun: resume : clear step\n");
2452 fprintf_unfiltered (gdb_stdlog
,
2453 "infrun: resume (step=%d, signal=%s), "
2454 "trap_expected=%d, current thread [%s] at %s\n",
2455 step
, gdb_signal_to_symbol_string (sig
),
2456 tp
->control
.trap_expected
,
2457 target_pid_to_str (inferior_ptid
),
2458 paddress (gdbarch
, pc
));
2460 /* Normally, by the time we reach `resume', the breakpoints are either
2461 removed or inserted, as appropriate. The exception is if we're sitting
2462 at a permanent breakpoint; we need to step over it, but permanent
2463 breakpoints can't be removed. So we have to test for it here. */
2464 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2466 if (sig
!= GDB_SIGNAL_0
)
2468 /* We have a signal to pass to the inferior. The resume
2469 may, or may not take us to the signal handler. If this
2470 is a step, we'll need to stop in the signal handler, if
2471 there's one, (if the target supports stepping into
2472 handlers), or in the next mainline instruction, if
2473 there's no handler. If this is a continue, we need to be
2474 sure to run the handler with all breakpoints inserted.
2475 In all cases, set a breakpoint at the current address
2476 (where the handler returns to), and once that breakpoint
2477 is hit, resume skipping the permanent breakpoint. If
2478 that breakpoint isn't hit, then we've stepped into the
2479 signal handler (or hit some other event). We'll delete
2480 the step-resume breakpoint then. */
2483 fprintf_unfiltered (gdb_stdlog
,
2484 "infrun: resume: skipping permanent breakpoint, "
2485 "deliver signal first\n");
2487 clear_step_over_info ();
2488 tp
->control
.trap_expected
= 0;
2490 if (tp
->control
.step_resume_breakpoint
== NULL
)
2492 /* Set a "high-priority" step-resume, as we don't want
2493 user breakpoints at PC to trigger (again) when this
2495 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2496 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2498 tp
->step_after_step_resume_breakpoint
= step
;
2501 insert_breakpoints ();
2505 /* There's no signal to pass, we can go ahead and skip the
2506 permanent breakpoint manually. */
2508 fprintf_unfiltered (gdb_stdlog
,
2509 "infrun: resume: skipping permanent breakpoint\n");
2510 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2511 /* Update pc to reflect the new address from which we will
2512 execute instructions. */
2513 pc
= regcache_read_pc (regcache
);
2517 /* We've already advanced the PC, so the stepping part
2518 is done. Now we need to arrange for a trap to be
2519 reported to handle_inferior_event. Set a breakpoint
2520 at the current PC, and run to it. Don't update
2521 prev_pc, because if we end in
2522 switch_back_to_stepped_thread, we want the "expected
2523 thread advanced also" branch to be taken. IOW, we
2524 don't want this thread to step further from PC
2526 gdb_assert (!step_over_info_valid_p ());
2527 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2528 insert_breakpoints ();
2530 resume_ptid
= internal_resume_ptid (user_step
);
2531 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2532 discard_cleanups (old_cleanups
);
2539 /* If we have a breakpoint to step over, make sure to do a single
2540 step only. Same if we have software watchpoints. */
2541 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2542 tp
->control
.may_range_step
= 0;
2544 /* If enabled, step over breakpoints by executing a copy of the
2545 instruction at a different address.
2547 We can't use displaced stepping when we have a signal to deliver;
2548 the comments for displaced_step_prepare explain why. The
2549 comments in the handle_inferior event for dealing with 'random
2550 signals' explain what we do instead.
2552 We can't use displaced stepping when we are waiting for vfork_done
2553 event, displaced stepping breaks the vfork child similarly as single
2554 step software breakpoint. */
2555 if (tp
->control
.trap_expected
2556 && use_displaced_stepping (tp
)
2557 && !step_over_info_valid_p ()
2558 && sig
== GDB_SIGNAL_0
2559 && !current_inferior ()->waiting_for_vfork_done
)
2561 int prepared
= displaced_step_prepare (inferior_ptid
);
2566 fprintf_unfiltered (gdb_stdlog
,
2567 "Got placed in step-over queue\n");
2569 tp
->control
.trap_expected
= 0;
2570 discard_cleanups (old_cleanups
);
2573 else if (prepared
< 0)
2575 /* Fallback to stepping over the breakpoint in-line. */
2577 if (target_is_non_stop_p ())
2578 stop_all_threads ();
2580 set_step_over_info (get_regcache_aspace (regcache
),
2581 regcache_read_pc (regcache
), 0);
2583 step
= maybe_software_singlestep (gdbarch
, pc
);
2585 insert_breakpoints ();
2587 else if (prepared
> 0)
2589 struct displaced_step_inferior_state
*displaced
;
2591 /* Update pc to reflect the new address from which we will
2592 execute instructions due to displaced stepping. */
2593 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2595 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2596 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2597 displaced
->step_closure
);
2601 /* Do we need to do it the hard way, w/temp breakpoints? */
2603 step
= maybe_software_singlestep (gdbarch
, pc
);
2605 /* Currently, our software single-step implementation leads to different
2606 results than hardware single-stepping in one situation: when stepping
2607 into delivering a signal which has an associated signal handler,
2608 hardware single-step will stop at the first instruction of the handler,
2609 while software single-step will simply skip execution of the handler.
2611 For now, this difference in behavior is accepted since there is no
2612 easy way to actually implement single-stepping into a signal handler
2613 without kernel support.
2615 However, there is one scenario where this difference leads to follow-on
2616 problems: if we're stepping off a breakpoint by removing all breakpoints
2617 and then single-stepping. In this case, the software single-step
2618 behavior means that even if there is a *breakpoint* in the signal
2619 handler, GDB still would not stop.
2621 Fortunately, we can at least fix this particular issue. We detect
2622 here the case where we are about to deliver a signal while software
2623 single-stepping with breakpoints removed. In this situation, we
2624 revert the decisions to remove all breakpoints and insert single-
2625 step breakpoints, and instead we install a step-resume breakpoint
2626 at the current address, deliver the signal without stepping, and
2627 once we arrive back at the step-resume breakpoint, actually step
2628 over the breakpoint we originally wanted to step over. */
2629 if (thread_has_single_step_breakpoints_set (tp
)
2630 && sig
!= GDB_SIGNAL_0
2631 && step_over_info_valid_p ())
2633 /* If we have nested signals or a pending signal is delivered
2634 immediately after a handler returns, might might already have
2635 a step-resume breakpoint set on the earlier handler. We cannot
2636 set another step-resume breakpoint; just continue on until the
2637 original breakpoint is hit. */
2638 if (tp
->control
.step_resume_breakpoint
== NULL
)
2640 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2641 tp
->step_after_step_resume_breakpoint
= 1;
2644 delete_single_step_breakpoints (tp
);
2646 clear_step_over_info ();
2647 tp
->control
.trap_expected
= 0;
2649 insert_breakpoints ();
2652 /* If STEP is set, it's a request to use hardware stepping
2653 facilities. But in that case, we should never
2654 use singlestep breakpoint. */
2655 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2657 /* Decide the set of threads to ask the target to resume. */
2658 if (tp
->control
.trap_expected
)
2660 /* We're allowing a thread to run past a breakpoint it has
2661 hit, either by single-stepping the thread with the breakpoint
2662 removed, or by displaced stepping, with the breakpoint inserted.
2663 In the former case, we need to single-step only this thread,
2664 and keep others stopped, as they can miss this breakpoint if
2665 allowed to run. That's not really a problem for displaced
2666 stepping, but, we still keep other threads stopped, in case
2667 another thread is also stopped for a breakpoint waiting for
2668 its turn in the displaced stepping queue. */
2669 resume_ptid
= inferior_ptid
;
2672 resume_ptid
= internal_resume_ptid (user_step
);
2674 if (execution_direction
!= EXEC_REVERSE
2675 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2677 /* There are two cases where we currently need to step a
2678 breakpoint instruction when we have a signal to deliver:
2680 - See handle_signal_stop where we handle random signals that
2681 could take out us out of the stepping range. Normally, in
2682 that case we end up continuing (instead of stepping) over the
2683 signal handler with a breakpoint at PC, but there are cases
2684 where we should _always_ single-step, even if we have a
2685 step-resume breakpoint, like when a software watchpoint is
2686 set. Assuming single-stepping and delivering a signal at the
2687 same time would takes us to the signal handler, then we could
2688 have removed the breakpoint at PC to step over it. However,
2689 some hardware step targets (like e.g., Mac OS) can't step
2690 into signal handlers, and for those, we need to leave the
2691 breakpoint at PC inserted, as otherwise if the handler
2692 recurses and executes PC again, it'll miss the breakpoint.
2693 So we leave the breakpoint inserted anyway, but we need to
2694 record that we tried to step a breakpoint instruction, so
2695 that adjust_pc_after_break doesn't end up confused.
2697 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2698 in one thread after another thread that was stepping had been
2699 momentarily paused for a step-over. When we re-resume the
2700 stepping thread, it may be resumed from that address with a
2701 breakpoint that hasn't trapped yet. Seen with
2702 gdb.threads/non-stop-fair-events.exp, on targets that don't
2703 do displaced stepping. */
2706 fprintf_unfiltered (gdb_stdlog
,
2707 "infrun: resume: [%s] stepped breakpoint\n",
2708 target_pid_to_str (tp
->ptid
));
2710 tp
->stepped_breakpoint
= 1;
2712 /* Most targets can step a breakpoint instruction, thus
2713 executing it normally. But if this one cannot, just
2714 continue and we will hit it anyway. */
2715 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2720 && tp
->control
.trap_expected
2721 && use_displaced_stepping (tp
)
2722 && !step_over_info_valid_p ())
2724 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2725 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2726 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2729 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2730 paddress (resume_gdbarch
, actual_pc
));
2731 read_memory (actual_pc
, buf
, sizeof (buf
));
2732 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2735 if (tp
->control
.may_range_step
)
2737 /* If we're resuming a thread with the PC out of the step
2738 range, then we're doing some nested/finer run control
2739 operation, like stepping the thread out of the dynamic
2740 linker or the displaced stepping scratch pad. We
2741 shouldn't have allowed a range step then. */
2742 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2745 do_target_resume (resume_ptid
, step
, sig
);
2747 discard_cleanups (old_cleanups
);
2754 /* Counter that tracks number of user visible stops. This can be used
2755 to tell whether a command has proceeded the inferior past the
2756 current location. This allows e.g., inferior function calls in
2757 breakpoint commands to not interrupt the command list. When the
2758 call finishes successfully, the inferior is standing at the same
2759 breakpoint as if nothing happened (and so we don't call
2761 static ULONGEST current_stop_id
;
2768 return current_stop_id
;
2771 /* Called when we report a user visible stop. */
2779 /* Clear out all variables saying what to do when inferior is continued.
2780 First do this, then set the ones you want, then call `proceed'. */
2783 clear_proceed_status_thread (struct thread_info
*tp
)
2786 fprintf_unfiltered (gdb_stdlog
,
2787 "infrun: clear_proceed_status_thread (%s)\n",
2788 target_pid_to_str (tp
->ptid
));
2790 /* If we're starting a new sequence, then the previous finished
2791 single-step is no longer relevant. */
2792 if (tp
->suspend
.waitstatus_pending_p
)
2794 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2797 fprintf_unfiltered (gdb_stdlog
,
2798 "infrun: clear_proceed_status: pending "
2799 "event of %s was a finished step. "
2801 target_pid_to_str (tp
->ptid
));
2803 tp
->suspend
.waitstatus_pending_p
= 0;
2804 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2806 else if (debug_infrun
)
2810 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2811 fprintf_unfiltered (gdb_stdlog
,
2812 "infrun: clear_proceed_status_thread: thread %s "
2813 "has pending wait status %s "
2814 "(currently_stepping=%d).\n",
2815 target_pid_to_str (tp
->ptid
), statstr
,
2816 currently_stepping (tp
));
2821 /* If this signal should not be seen by program, give it zero.
2822 Used for debugging signals. */
2823 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2824 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2826 thread_fsm_delete (tp
->thread_fsm
);
2827 tp
->thread_fsm
= NULL
;
2829 tp
->control
.trap_expected
= 0;
2830 tp
->control
.step_range_start
= 0;
2831 tp
->control
.step_range_end
= 0;
2832 tp
->control
.may_range_step
= 0;
2833 tp
->control
.step_frame_id
= null_frame_id
;
2834 tp
->control
.step_stack_frame_id
= null_frame_id
;
2835 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2836 tp
->control
.step_start_function
= NULL
;
2837 tp
->stop_requested
= 0;
2839 tp
->control
.stop_step
= 0;
2841 tp
->control
.proceed_to_finish
= 0;
2843 tp
->control
.command_interp
= NULL
;
2844 tp
->control
.stepping_command
= 0;
2846 /* Discard any remaining commands or status from previous stop. */
2847 bpstat_clear (&tp
->control
.stop_bpstat
);
2851 clear_proceed_status (int step
)
2853 /* With scheduler-locking replay, stop replaying other threads if we're
2854 not replaying the user-visible resume ptid.
2856 This is a convenience feature to not require the user to explicitly
2857 stop replaying the other threads. We're assuming that the user's
2858 intent is to resume tracing the recorded process. */
2859 if (!non_stop
&& scheduler_mode
== schedlock_replay
2860 && target_record_is_replaying (minus_one_ptid
)
2861 && !target_record_will_replay (user_visible_resume_ptid (step
),
2862 execution_direction
))
2863 target_record_stop_replaying ();
2867 struct thread_info
*tp
;
2870 resume_ptid
= user_visible_resume_ptid (step
);
2872 /* In all-stop mode, delete the per-thread status of all threads
2873 we're about to resume, implicitly and explicitly. */
2874 ALL_NON_EXITED_THREADS (tp
)
2876 if (!ptid_match (tp
->ptid
, resume_ptid
))
2878 clear_proceed_status_thread (tp
);
2882 if (!ptid_equal (inferior_ptid
, null_ptid
))
2884 struct inferior
*inferior
;
2888 /* If in non-stop mode, only delete the per-thread status of
2889 the current thread. */
2890 clear_proceed_status_thread (inferior_thread ());
2893 inferior
= current_inferior ();
2894 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2897 observer_notify_about_to_proceed ();
2900 /* Returns true if TP is still stopped at a breakpoint that needs
2901 stepping-over in order to make progress. If the breakpoint is gone
2902 meanwhile, we can skip the whole step-over dance. */
2905 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2907 if (tp
->stepping_over_breakpoint
)
2909 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2911 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2912 regcache_read_pc (regcache
))
2913 == ordinary_breakpoint_here
)
2916 tp
->stepping_over_breakpoint
= 0;
2922 /* Check whether thread TP still needs to start a step-over in order
2923 to make progress when resumed. Returns an bitwise or of enum
2924 step_over_what bits, indicating what needs to be stepped over. */
2926 static step_over_what
2927 thread_still_needs_step_over (struct thread_info
*tp
)
2929 struct inferior
*inf
= find_inferior_ptid (tp
->ptid
);
2930 step_over_what what
= 0;
2932 if (thread_still_needs_step_over_bp (tp
))
2933 what
|= STEP_OVER_BREAKPOINT
;
2935 if (tp
->stepping_over_watchpoint
2936 && !target_have_steppable_watchpoint
)
2937 what
|= STEP_OVER_WATCHPOINT
;
2942 /* Returns true if scheduler locking applies. STEP indicates whether
2943 we're about to do a step/next-like command to a thread. */
2946 schedlock_applies (struct thread_info
*tp
)
2948 return (scheduler_mode
== schedlock_on
2949 || (scheduler_mode
== schedlock_step
2950 && tp
->control
.stepping_command
)
2951 || (scheduler_mode
== schedlock_replay
2952 && target_record_will_replay (minus_one_ptid
,
2953 execution_direction
)));
2956 /* Basic routine for continuing the program in various fashions.
2958 ADDR is the address to resume at, or -1 for resume where stopped.
2959 SIGGNAL is the signal to give it, or 0 for none,
2960 or -1 for act according to how it stopped.
2961 STEP is nonzero if should trap after one instruction.
2962 -1 means return after that and print nothing.
2963 You should probably set various step_... variables
2964 before calling here, if you are stepping.
2966 You should call clear_proceed_status before calling proceed. */
2969 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2971 struct regcache
*regcache
;
2972 struct gdbarch
*gdbarch
;
2973 struct thread_info
*tp
;
2975 struct address_space
*aspace
;
2977 struct execution_control_state ecss
;
2978 struct execution_control_state
*ecs
= &ecss
;
2979 struct cleanup
*old_chain
;
2982 /* If we're stopped at a fork/vfork, follow the branch set by the
2983 "set follow-fork-mode" command; otherwise, we'll just proceed
2984 resuming the current thread. */
2985 if (!follow_fork ())
2987 /* The target for some reason decided not to resume. */
2989 if (target_can_async_p ())
2990 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2994 /* We'll update this if & when we switch to a new thread. */
2995 previous_inferior_ptid
= inferior_ptid
;
2997 regcache
= get_current_regcache ();
2998 gdbarch
= get_regcache_arch (regcache
);
2999 aspace
= get_regcache_aspace (regcache
);
3000 pc
= regcache_read_pc (regcache
);
3001 tp
= inferior_thread ();
3003 /* Fill in with reasonable starting values. */
3004 init_thread_stepping_state (tp
);
3006 gdb_assert (!thread_is_in_step_over_chain (tp
));
3008 if (addr
== (CORE_ADDR
) -1)
3011 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3012 && execution_direction
!= EXEC_REVERSE
)
3013 /* There is a breakpoint at the address we will resume at,
3014 step one instruction before inserting breakpoints so that
3015 we do not stop right away (and report a second hit at this
3018 Note, we don't do this in reverse, because we won't
3019 actually be executing the breakpoint insn anyway.
3020 We'll be (un-)executing the previous instruction. */
3021 tp
->stepping_over_breakpoint
= 1;
3022 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3023 && gdbarch_single_step_through_delay (gdbarch
,
3024 get_current_frame ()))
3025 /* We stepped onto an instruction that needs to be stepped
3026 again before re-inserting the breakpoint, do so. */
3027 tp
->stepping_over_breakpoint
= 1;
3031 regcache_write_pc (regcache
, addr
);
3034 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3035 tp
->suspend
.stop_signal
= siggnal
;
3037 /* Record the interpreter that issued the execution command that
3038 caused this thread to resume. If the top level interpreter is
3039 MI/async, and the execution command was a CLI command
3040 (next/step/etc.), we'll want to print stop event output to the MI
3041 console channel (the stepped-to line, etc.), as if the user
3042 entered the execution command on a real GDB console. */
3043 tp
->control
.command_interp
= command_interp ();
3045 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
3047 /* If an exception is thrown from this point on, make sure to
3048 propagate GDB's knowledge of the executing state to the
3049 frontend/user running state. */
3050 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
3052 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3053 threads (e.g., we might need to set threads stepping over
3054 breakpoints first), from the user/frontend's point of view, all
3055 threads in RESUME_PTID are now running. Unless we're calling an
3056 inferior function, as in that case we pretend the inferior
3057 doesn't run at all. */
3058 if (!tp
->control
.in_infcall
)
3059 set_running (resume_ptid
, 1);
3062 fprintf_unfiltered (gdb_stdlog
,
3063 "infrun: proceed (addr=%s, signal=%s)\n",
3064 paddress (gdbarch
, addr
),
3065 gdb_signal_to_symbol_string (siggnal
));
3067 annotate_starting ();
3069 /* Make sure that output from GDB appears before output from the
3071 gdb_flush (gdb_stdout
);
3073 /* In a multi-threaded task we may select another thread and
3074 then continue or step.
3076 But if a thread that we're resuming had stopped at a breakpoint,
3077 it will immediately cause another breakpoint stop without any
3078 execution (i.e. it will report a breakpoint hit incorrectly). So
3079 we must step over it first.
3081 Look for threads other than the current (TP) that reported a
3082 breakpoint hit and haven't been resumed yet since. */
3084 /* If scheduler locking applies, we can avoid iterating over all
3086 if (!non_stop
&& !schedlock_applies (tp
))
3088 struct thread_info
*current
= tp
;
3090 ALL_NON_EXITED_THREADS (tp
)
3092 /* Ignore the current thread here. It's handled
3097 /* Ignore threads of processes we're not resuming. */
3098 if (!ptid_match (tp
->ptid
, resume_ptid
))
3101 if (!thread_still_needs_step_over (tp
))
3104 gdb_assert (!thread_is_in_step_over_chain (tp
));
3107 fprintf_unfiltered (gdb_stdlog
,
3108 "infrun: need to step-over [%s] first\n",
3109 target_pid_to_str (tp
->ptid
));
3111 thread_step_over_chain_enqueue (tp
);
3117 /* Enqueue the current thread last, so that we move all other
3118 threads over their breakpoints first. */
3119 if (tp
->stepping_over_breakpoint
)
3120 thread_step_over_chain_enqueue (tp
);
3122 /* If the thread isn't started, we'll still need to set its prev_pc,
3123 so that switch_back_to_stepped_thread knows the thread hasn't
3124 advanced. Must do this before resuming any thread, as in
3125 all-stop/remote, once we resume we can't send any other packet
3126 until the target stops again. */
3127 tp
->prev_pc
= regcache_read_pc (regcache
);
3129 started
= start_step_over ();
3131 if (step_over_info_valid_p ())
3133 /* Either this thread started a new in-line step over, or some
3134 other thread was already doing one. In either case, don't
3135 resume anything else until the step-over is finished. */
3137 else if (started
&& !target_is_non_stop_p ())
3139 /* A new displaced stepping sequence was started. In all-stop,
3140 we can't talk to the target anymore until it next stops. */
3142 else if (!non_stop
&& target_is_non_stop_p ())
3144 /* In all-stop, but the target is always in non-stop mode.
3145 Start all other threads that are implicitly resumed too. */
3146 ALL_NON_EXITED_THREADS (tp
)
3148 /* Ignore threads of processes we're not resuming. */
3149 if (!ptid_match (tp
->ptid
, resume_ptid
))
3155 fprintf_unfiltered (gdb_stdlog
,
3156 "infrun: proceed: [%s] resumed\n",
3157 target_pid_to_str (tp
->ptid
));
3158 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3162 if (thread_is_in_step_over_chain (tp
))
3165 fprintf_unfiltered (gdb_stdlog
,
3166 "infrun: proceed: [%s] needs step-over\n",
3167 target_pid_to_str (tp
->ptid
));
3172 fprintf_unfiltered (gdb_stdlog
,
3173 "infrun: proceed: resuming %s\n",
3174 target_pid_to_str (tp
->ptid
));
3176 reset_ecs (ecs
, tp
);
3177 switch_to_thread (tp
->ptid
);
3178 keep_going_pass_signal (ecs
);
3179 if (!ecs
->wait_some_more
)
3180 error (_("Command aborted."));
3183 else if (!tp
->resumed
&& !thread_is_in_step_over_chain (tp
))
3185 /* The thread wasn't started, and isn't queued, run it now. */
3186 reset_ecs (ecs
, tp
);
3187 switch_to_thread (tp
->ptid
);
3188 keep_going_pass_signal (ecs
);
3189 if (!ecs
->wait_some_more
)
3190 error (_("Command aborted."));
3193 discard_cleanups (old_chain
);
3195 /* Tell the event loop to wait for it to stop. If the target
3196 supports asynchronous execution, it'll do this from within
3198 if (!target_can_async_p ())
3199 mark_async_event_handler (infrun_async_inferior_event_token
);
3203 /* Start remote-debugging of a machine over a serial link. */
3206 start_remote (int from_tty
)
3208 struct inferior
*inferior
;
3210 inferior
= current_inferior ();
3211 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3213 /* Always go on waiting for the target, regardless of the mode. */
3214 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3215 indicate to wait_for_inferior that a target should timeout if
3216 nothing is returned (instead of just blocking). Because of this,
3217 targets expecting an immediate response need to, internally, set
3218 things up so that the target_wait() is forced to eventually
3220 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3221 differentiate to its caller what the state of the target is after
3222 the initial open has been performed. Here we're assuming that
3223 the target has stopped. It should be possible to eventually have
3224 target_open() return to the caller an indication that the target
3225 is currently running and GDB state should be set to the same as
3226 for an async run. */
3227 wait_for_inferior ();
3229 /* Now that the inferior has stopped, do any bookkeeping like
3230 loading shared libraries. We want to do this before normal_stop,
3231 so that the displayed frame is up to date. */
3232 post_create_inferior (¤t_target
, from_tty
);
3237 /* Initialize static vars when a new inferior begins. */
3240 init_wait_for_inferior (void)
3242 /* These are meaningless until the first time through wait_for_inferior. */
3244 breakpoint_init_inferior (inf_starting
);
3246 clear_proceed_status (0);
3248 target_last_wait_ptid
= minus_one_ptid
;
3250 previous_inferior_ptid
= inferior_ptid
;
3252 /* Discard any skipped inlined frames. */
3253 clear_inline_frame_state (minus_one_ptid
);
3258 static void handle_inferior_event (struct execution_control_state
*ecs
);
3260 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3261 struct execution_control_state
*ecs
);
3262 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3263 struct execution_control_state
*ecs
);
3264 static void handle_signal_stop (struct execution_control_state
*ecs
);
3265 static void check_exception_resume (struct execution_control_state
*,
3266 struct frame_info
*);
3268 static void end_stepping_range (struct execution_control_state
*ecs
);
3269 static void stop_waiting (struct execution_control_state
*ecs
);
3270 static void keep_going (struct execution_control_state
*ecs
);
3271 static void process_event_stop_test (struct execution_control_state
*ecs
);
3272 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3274 /* Callback for iterate over threads. If the thread is stopped, but
3275 the user/frontend doesn't know about that yet, go through
3276 normal_stop, as if the thread had just stopped now. ARG points at
3277 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
3278 ptid_is_pid(PTID) is true, applies to all threads of the process
3279 pointed at by PTID. Otherwise, apply only to the thread pointed by
3283 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
3285 ptid_t ptid
= * (ptid_t
*) arg
;
3287 if ((ptid_equal (info
->ptid
, ptid
)
3288 || ptid_equal (minus_one_ptid
, ptid
)
3289 || (ptid_is_pid (ptid
)
3290 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
3291 && is_running (info
->ptid
)
3292 && !is_executing (info
->ptid
))
3294 struct cleanup
*old_chain
;
3295 struct execution_control_state ecss
;
3296 struct execution_control_state
*ecs
= &ecss
;
3298 memset (ecs
, 0, sizeof (*ecs
));
3300 old_chain
= make_cleanup_restore_current_thread ();
3302 overlay_cache_invalid
= 1;
3303 /* Flush target cache before starting to handle each event.
3304 Target was running and cache could be stale. This is just a
3305 heuristic. Running threads may modify target memory, but we
3306 don't get any event. */
3307 target_dcache_invalidate ();
3309 /* Go through handle_inferior_event/normal_stop, so we always
3310 have consistent output as if the stop event had been
3312 ecs
->ptid
= info
->ptid
;
3313 ecs
->event_thread
= info
;
3314 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
3315 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
3317 handle_inferior_event (ecs
);
3319 if (!ecs
->wait_some_more
)
3321 /* Cancel any running execution command. */
3322 thread_cancel_execution_command (info
);
3327 do_cleanups (old_chain
);
3333 /* This function is attached as a "thread_stop_requested" observer.
3334 Cleanup local state that assumed the PTID was to be resumed, and
3335 report the stop to the frontend. */
3338 infrun_thread_stop_requested (ptid_t ptid
)
3340 struct thread_info
*tp
;
3342 /* PTID was requested to stop. Remove matching threads from the
3343 step-over queue, so we don't try to resume them
3345 ALL_NON_EXITED_THREADS (tp
)
3346 if (ptid_match (tp
->ptid
, ptid
))
3348 if (thread_is_in_step_over_chain (tp
))
3349 thread_step_over_chain_remove (tp
);
3352 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
3356 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3358 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3359 nullify_last_target_wait_ptid ();
3362 /* Delete the step resume, single-step and longjmp/exception resume
3363 breakpoints of TP. */
3366 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3368 delete_step_resume_breakpoint (tp
);
3369 delete_exception_resume_breakpoint (tp
);
3370 delete_single_step_breakpoints (tp
);
3373 /* If the target still has execution, call FUNC for each thread that
3374 just stopped. In all-stop, that's all the non-exited threads; in
3375 non-stop, that's the current thread, only. */
3377 typedef void (*for_each_just_stopped_thread_callback_func
)
3378 (struct thread_info
*tp
);
3381 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3383 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3386 if (target_is_non_stop_p ())
3388 /* If in non-stop mode, only the current thread stopped. */
3389 func (inferior_thread ());
3393 struct thread_info
*tp
;
3395 /* In all-stop mode, all threads have stopped. */
3396 ALL_NON_EXITED_THREADS (tp
)
3403 /* Delete the step resume and longjmp/exception resume breakpoints of
3404 the threads that just stopped. */
3407 delete_just_stopped_threads_infrun_breakpoints (void)
3409 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3412 /* Delete the single-step breakpoints of the threads that just
3416 delete_just_stopped_threads_single_step_breakpoints (void)
3418 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3421 /* A cleanup wrapper. */
3424 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3426 delete_just_stopped_threads_infrun_breakpoints ();
3432 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3433 const struct target_waitstatus
*ws
)
3435 char *status_string
= target_waitstatus_to_string (ws
);
3436 struct ui_file
*tmp_stream
= mem_fileopen ();
3439 /* The text is split over several lines because it was getting too long.
3440 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3441 output as a unit; we want only one timestamp printed if debug_timestamp
3444 fprintf_unfiltered (tmp_stream
,
3445 "infrun: target_wait (%d.%ld.%ld",
3446 ptid_get_pid (waiton_ptid
),
3447 ptid_get_lwp (waiton_ptid
),
3448 ptid_get_tid (waiton_ptid
));
3449 if (ptid_get_pid (waiton_ptid
) != -1)
3450 fprintf_unfiltered (tmp_stream
,
3451 " [%s]", target_pid_to_str (waiton_ptid
));
3452 fprintf_unfiltered (tmp_stream
, ", status) =\n");
3453 fprintf_unfiltered (tmp_stream
,
3454 "infrun: %d.%ld.%ld [%s],\n",
3455 ptid_get_pid (result_ptid
),
3456 ptid_get_lwp (result_ptid
),
3457 ptid_get_tid (result_ptid
),
3458 target_pid_to_str (result_ptid
));
3459 fprintf_unfiltered (tmp_stream
,
3463 text
= ui_file_xstrdup (tmp_stream
, NULL
);
3465 /* This uses %s in part to handle %'s in the text, but also to avoid
3466 a gcc error: the format attribute requires a string literal. */
3467 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
3469 xfree (status_string
);
3471 ui_file_delete (tmp_stream
);
3474 /* Select a thread at random, out of those which are resumed and have
3477 static struct thread_info
*
3478 random_pending_event_thread (ptid_t waiton_ptid
)
3480 struct thread_info
*event_tp
;
3482 int random_selector
;
3484 /* First see how many events we have. Count only resumed threads
3485 that have an event pending. */
3486 ALL_NON_EXITED_THREADS (event_tp
)
3487 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3488 && event_tp
->resumed
3489 && event_tp
->suspend
.waitstatus_pending_p
)
3492 if (num_events
== 0)
3495 /* Now randomly pick a thread out of those that have had events. */
3496 random_selector
= (int)
3497 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3499 if (debug_infrun
&& num_events
> 1)
3500 fprintf_unfiltered (gdb_stdlog
,
3501 "infrun: Found %d events, selecting #%d\n",
3502 num_events
, random_selector
);
3504 /* Select the Nth thread that has had an event. */
3505 ALL_NON_EXITED_THREADS (event_tp
)
3506 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3507 && event_tp
->resumed
3508 && event_tp
->suspend
.waitstatus_pending_p
)
3509 if (random_selector
-- == 0)
3515 /* Wrapper for target_wait that first checks whether threads have
3516 pending statuses to report before actually asking the target for
3520 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3523 struct thread_info
*tp
;
3525 /* First check if there is a resumed thread with a wait status
3527 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
3529 tp
= random_pending_event_thread (ptid
);
3534 fprintf_unfiltered (gdb_stdlog
,
3535 "infrun: Waiting for specific thread %s.\n",
3536 target_pid_to_str (ptid
));
3538 /* We have a specific thread to check. */
3539 tp
= find_thread_ptid (ptid
);
3540 gdb_assert (tp
!= NULL
);
3541 if (!tp
->suspend
.waitstatus_pending_p
)
3546 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3547 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3549 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
3550 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3554 pc
= regcache_read_pc (regcache
);
3556 if (pc
!= tp
->suspend
.stop_pc
)
3559 fprintf_unfiltered (gdb_stdlog
,
3560 "infrun: PC of %s changed. was=%s, now=%s\n",
3561 target_pid_to_str (tp
->ptid
),
3562 paddress (gdbarch
, tp
->prev_pc
),
3563 paddress (gdbarch
, pc
));
3566 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3569 fprintf_unfiltered (gdb_stdlog
,
3570 "infrun: previous breakpoint of %s, at %s gone\n",
3571 target_pid_to_str (tp
->ptid
),
3572 paddress (gdbarch
, pc
));
3580 fprintf_unfiltered (gdb_stdlog
,
3581 "infrun: pending event of %s cancelled.\n",
3582 target_pid_to_str (tp
->ptid
));
3584 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3585 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3595 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3596 fprintf_unfiltered (gdb_stdlog
,
3597 "infrun: Using pending wait status %s for %s.\n",
3599 target_pid_to_str (tp
->ptid
));
3603 /* Now that we've selected our final event LWP, un-adjust its PC
3604 if it was a software breakpoint (and the target doesn't
3605 always adjust the PC itself). */
3606 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3607 && !target_supports_stopped_by_sw_breakpoint ())
3609 struct regcache
*regcache
;
3610 struct gdbarch
*gdbarch
;
3613 regcache
= get_thread_regcache (tp
->ptid
);
3614 gdbarch
= get_regcache_arch (regcache
);
3616 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3621 pc
= regcache_read_pc (regcache
);
3622 regcache_write_pc (regcache
, pc
+ decr_pc
);
3626 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3627 *status
= tp
->suspend
.waitstatus
;
3628 tp
->suspend
.waitstatus_pending_p
= 0;
3630 /* Wake up the event loop again, until all pending events are
3632 if (target_is_async_p ())
3633 mark_async_event_handler (infrun_async_inferior_event_token
);
3637 /* But if we don't find one, we'll have to wait. */
3639 if (deprecated_target_wait_hook
)
3640 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3642 event_ptid
= target_wait (ptid
, status
, options
);
3647 /* Prepare and stabilize the inferior for detaching it. E.g.,
3648 detaching while a thread is displaced stepping is a recipe for
3649 crashing it, as nothing would readjust the PC out of the scratch
3653 prepare_for_detach (void)
3655 struct inferior
*inf
= current_inferior ();
3656 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3657 struct cleanup
*old_chain_1
;
3658 struct displaced_step_inferior_state
*displaced
;
3660 displaced
= get_displaced_stepping_state (inf
->pid
);
3662 /* Is any thread of this process displaced stepping? If not,
3663 there's nothing else to do. */
3664 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3668 fprintf_unfiltered (gdb_stdlog
,
3669 "displaced-stepping in-process while detaching");
3671 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3674 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3676 struct cleanup
*old_chain_2
;
3677 struct execution_control_state ecss
;
3678 struct execution_control_state
*ecs
;
3681 memset (ecs
, 0, sizeof (*ecs
));
3683 overlay_cache_invalid
= 1;
3684 /* Flush target cache before starting to handle each event.
3685 Target was running and cache could be stale. This is just a
3686 heuristic. Running threads may modify target memory, but we
3687 don't get any event. */
3688 target_dcache_invalidate ();
3690 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3693 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3695 /* If an error happens while handling the event, propagate GDB's
3696 knowledge of the executing state to the frontend/user running
3698 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3701 /* Now figure out what to do with the result of the result. */
3702 handle_inferior_event (ecs
);
3704 /* No error, don't finish the state yet. */
3705 discard_cleanups (old_chain_2
);
3707 /* Breakpoints and watchpoints are not installed on the target
3708 at this point, and signals are passed directly to the
3709 inferior, so this must mean the process is gone. */
3710 if (!ecs
->wait_some_more
)
3712 discard_cleanups (old_chain_1
);
3713 error (_("Program exited while detaching"));
3717 discard_cleanups (old_chain_1
);
3720 /* Wait for control to return from inferior to debugger.
3722 If inferior gets a signal, we may decide to start it up again
3723 instead of returning. That is why there is a loop in this function.
3724 When this function actually returns it means the inferior
3725 should be left stopped and GDB should read more commands. */
3728 wait_for_inferior (void)
3730 struct cleanup
*old_cleanups
;
3731 struct cleanup
*thread_state_chain
;
3735 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3738 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3741 /* If an error happens while handling the event, propagate GDB's
3742 knowledge of the executing state to the frontend/user running
3744 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3748 struct execution_control_state ecss
;
3749 struct execution_control_state
*ecs
= &ecss
;
3750 ptid_t waiton_ptid
= minus_one_ptid
;
3752 memset (ecs
, 0, sizeof (*ecs
));
3754 overlay_cache_invalid
= 1;
3756 /* Flush target cache before starting to handle each event.
3757 Target was running and cache could be stale. This is just a
3758 heuristic. Running threads may modify target memory, but we
3759 don't get any event. */
3760 target_dcache_invalidate ();
3762 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3765 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3767 /* Now figure out what to do with the result of the result. */
3768 handle_inferior_event (ecs
);
3770 if (!ecs
->wait_some_more
)
3774 /* No error, don't finish the state yet. */
3775 discard_cleanups (thread_state_chain
);
3777 do_cleanups (old_cleanups
);
3780 /* Cleanup that reinstalls the readline callback handler, if the
3781 target is running in the background. If while handling the target
3782 event something triggered a secondary prompt, like e.g., a
3783 pagination prompt, we'll have removed the callback handler (see
3784 gdb_readline_wrapper_line). Need to do this as we go back to the
3785 event loop, ready to process further input. Note this has no
3786 effect if the handler hasn't actually been removed, because calling
3787 rl_callback_handler_install resets the line buffer, thus losing
3791 reinstall_readline_callback_handler_cleanup (void *arg
)
3793 if (!interpreter_async
)
3795 /* We're not going back to the top level event loop yet. Don't
3796 install the readline callback, as it'd prep the terminal,
3797 readline-style (raw, noecho) (e.g., --batch). We'll install
3798 it the next time the prompt is displayed, when we're ready
3803 if (async_command_editing_p
&& !sync_execution
)
3804 gdb_rl_callback_handler_reinstall ();
3807 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3808 that's just the event thread. In all-stop, that's all threads. */
3811 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3813 struct thread_info
*thr
= ecs
->event_thread
;
3815 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3816 thread_fsm_clean_up (thr
->thread_fsm
);
3820 ALL_NON_EXITED_THREADS (thr
)
3822 if (thr
->thread_fsm
== NULL
)
3824 if (thr
== ecs
->event_thread
)
3827 switch_to_thread (thr
->ptid
);
3828 thread_fsm_clean_up (thr
->thread_fsm
);
3831 if (ecs
->event_thread
!= NULL
)
3832 switch_to_thread (ecs
->event_thread
->ptid
);
3836 /* A cleanup that restores the execution direction to the value saved
3840 restore_execution_direction (void *arg
)
3842 enum exec_direction_kind
*save_exec_dir
= (enum exec_direction_kind
*) arg
;
3844 execution_direction
= *save_exec_dir
;
3847 /* Asynchronous version of wait_for_inferior. It is called by the
3848 event loop whenever a change of state is detected on the file
3849 descriptor corresponding to the target. It can be called more than
3850 once to complete a single execution command. In such cases we need
3851 to keep the state in a global variable ECSS. If it is the last time
3852 that this function is called for a single execution command, then
3853 report to the user that the inferior has stopped, and do the
3854 necessary cleanups. */
3857 fetch_inferior_event (void *client_data
)
3859 struct execution_control_state ecss
;
3860 struct execution_control_state
*ecs
= &ecss
;
3861 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3862 struct cleanup
*ts_old_chain
;
3863 int was_sync
= sync_execution
;
3864 enum exec_direction_kind save_exec_dir
= execution_direction
;
3866 ptid_t waiton_ptid
= minus_one_ptid
;
3868 memset (ecs
, 0, sizeof (*ecs
));
3870 /* End up with readline processing input, if necessary. */
3871 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3873 /* We're handling a live event, so make sure we're doing live
3874 debugging. If we're looking at traceframes while the target is
3875 running, we're going to need to get back to that mode after
3876 handling the event. */
3879 make_cleanup_restore_current_traceframe ();
3880 set_current_traceframe (-1);
3884 /* In non-stop mode, the user/frontend should not notice a thread
3885 switch due to internal events. Make sure we reverse to the
3886 user selected thread and frame after handling the event and
3887 running any breakpoint commands. */
3888 make_cleanup_restore_current_thread ();
3890 overlay_cache_invalid
= 1;
3891 /* Flush target cache before starting to handle each event. Target
3892 was running and cache could be stale. This is just a heuristic.
3893 Running threads may modify target memory, but we don't get any
3895 target_dcache_invalidate ();
3897 make_cleanup (restore_execution_direction
, &save_exec_dir
);
3898 execution_direction
= target_execution_direction ();
3900 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3901 target_can_async_p () ? TARGET_WNOHANG
: 0);
3904 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3906 /* If an error happens while handling the event, propagate GDB's
3907 knowledge of the executing state to the frontend/user running
3909 if (!target_is_non_stop_p ())
3910 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3912 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3914 /* Get executed before make_cleanup_restore_current_thread above to apply
3915 still for the thread which has thrown the exception. */
3916 make_bpstat_clear_actions_cleanup ();
3918 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3920 /* Now figure out what to do with the result of the result. */
3921 handle_inferior_event (ecs
);
3923 if (!ecs
->wait_some_more
)
3925 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3926 int should_stop
= 1;
3927 struct thread_info
*thr
= ecs
->event_thread
;
3928 int should_notify_stop
= 1;
3930 delete_just_stopped_threads_infrun_breakpoints ();
3934 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3936 if (thread_fsm
!= NULL
)
3937 should_stop
= thread_fsm_should_stop (thread_fsm
);
3946 clean_up_just_stopped_threads_fsms (ecs
);
3948 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3951 = thread_fsm_should_notify_stop (thr
->thread_fsm
);
3954 if (should_notify_stop
)
3958 /* We may not find an inferior if this was a process exit. */
3959 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3960 proceeded
= normal_stop ();
3964 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3971 /* No error, don't finish the thread states yet. */
3972 discard_cleanups (ts_old_chain
);
3974 /* Revert thread and frame. */
3975 do_cleanups (old_chain
);
3977 /* If the inferior was in sync execution mode, and now isn't,
3978 restore the prompt (a synchronous execution command has finished,
3979 and we're ready for input). */
3980 if (interpreter_async
&& was_sync
&& !sync_execution
)
3981 observer_notify_sync_execution_done ();
3985 && exec_done_display_p
3986 && (ptid_equal (inferior_ptid
, null_ptid
)
3987 || !is_running (inferior_ptid
)))
3988 printf_unfiltered (_("completed.\n"));
3991 /* Record the frame and location we're currently stepping through. */
3993 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3995 struct thread_info
*tp
= inferior_thread ();
3997 tp
->control
.step_frame_id
= get_frame_id (frame
);
3998 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4000 tp
->current_symtab
= sal
.symtab
;
4001 tp
->current_line
= sal
.line
;
4004 /* Clear context switchable stepping state. */
4007 init_thread_stepping_state (struct thread_info
*tss
)
4009 tss
->stepped_breakpoint
= 0;
4010 tss
->stepping_over_breakpoint
= 0;
4011 tss
->stepping_over_watchpoint
= 0;
4012 tss
->step_after_step_resume_breakpoint
= 0;
4015 /* Set the cached copy of the last ptid/waitstatus. */
4018 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
4020 target_last_wait_ptid
= ptid
;
4021 target_last_waitstatus
= status
;
4024 /* Return the cached copy of the last pid/waitstatus returned by
4025 target_wait()/deprecated_target_wait_hook(). The data is actually
4026 cached by handle_inferior_event(), which gets called immediately
4027 after target_wait()/deprecated_target_wait_hook(). */
4030 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
4032 *ptidp
= target_last_wait_ptid
;
4033 *status
= target_last_waitstatus
;
4037 nullify_last_target_wait_ptid (void)
4039 target_last_wait_ptid
= minus_one_ptid
;
4042 /* Switch thread contexts. */
4045 context_switch (ptid_t ptid
)
4047 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
4049 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
4050 target_pid_to_str (inferior_ptid
));
4051 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
4052 target_pid_to_str (ptid
));
4055 switch_to_thread (ptid
);
4058 /* If the target can't tell whether we've hit breakpoints
4059 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4060 check whether that could have been caused by a breakpoint. If so,
4061 adjust the PC, per gdbarch_decr_pc_after_break. */
4064 adjust_pc_after_break (struct thread_info
*thread
,
4065 struct target_waitstatus
*ws
)
4067 struct regcache
*regcache
;
4068 struct gdbarch
*gdbarch
;
4069 struct address_space
*aspace
;
4070 CORE_ADDR breakpoint_pc
, decr_pc
;
4072 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4073 we aren't, just return.
4075 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4076 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4077 implemented by software breakpoints should be handled through the normal
4080 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4081 different signals (SIGILL or SIGEMT for instance), but it is less
4082 clear where the PC is pointing afterwards. It may not match
4083 gdbarch_decr_pc_after_break. I don't know any specific target that
4084 generates these signals at breakpoints (the code has been in GDB since at
4085 least 1992) so I can not guess how to handle them here.
4087 In earlier versions of GDB, a target with
4088 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4089 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4090 target with both of these set in GDB history, and it seems unlikely to be
4091 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4093 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4096 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4099 /* In reverse execution, when a breakpoint is hit, the instruction
4100 under it has already been de-executed. The reported PC always
4101 points at the breakpoint address, so adjusting it further would
4102 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4105 B1 0x08000000 : INSN1
4106 B2 0x08000001 : INSN2
4108 PC -> 0x08000003 : INSN4
4110 Say you're stopped at 0x08000003 as above. Reverse continuing
4111 from that point should hit B2 as below. Reading the PC when the
4112 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4113 been de-executed already.
4115 B1 0x08000000 : INSN1
4116 B2 PC -> 0x08000001 : INSN2
4120 We can't apply the same logic as for forward execution, because
4121 we would wrongly adjust the PC to 0x08000000, since there's a
4122 breakpoint at PC - 1. We'd then report a hit on B1, although
4123 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4125 if (execution_direction
== EXEC_REVERSE
)
4128 /* If the target can tell whether the thread hit a SW breakpoint,
4129 trust it. Targets that can tell also adjust the PC
4131 if (target_supports_stopped_by_sw_breakpoint ())
4134 /* Note that relying on whether a breakpoint is planted in memory to
4135 determine this can fail. E.g,. the breakpoint could have been
4136 removed since. Or the thread could have been told to step an
4137 instruction the size of a breakpoint instruction, and only
4138 _after_ was a breakpoint inserted at its address. */
4140 /* If this target does not decrement the PC after breakpoints, then
4141 we have nothing to do. */
4142 regcache
= get_thread_regcache (thread
->ptid
);
4143 gdbarch
= get_regcache_arch (regcache
);
4145 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4149 aspace
= get_regcache_aspace (regcache
);
4151 /* Find the location where (if we've hit a breakpoint) the
4152 breakpoint would be. */
4153 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4155 /* If the target can't tell whether a software breakpoint triggered,
4156 fallback to figuring it out based on breakpoints we think were
4157 inserted in the target, and on whether the thread was stepped or
4160 /* Check whether there actually is a software breakpoint inserted at
4163 If in non-stop mode, a race condition is possible where we've
4164 removed a breakpoint, but stop events for that breakpoint were
4165 already queued and arrive later. To suppress those spurious
4166 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4167 and retire them after a number of stop events are reported. Note
4168 this is an heuristic and can thus get confused. The real fix is
4169 to get the "stopped by SW BP and needs adjustment" info out of
4170 the target/kernel (and thus never reach here; see above). */
4171 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4172 || (target_is_non_stop_p ()
4173 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4175 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4177 if (record_full_is_used ())
4178 record_full_gdb_operation_disable_set ();
4180 /* When using hardware single-step, a SIGTRAP is reported for both
4181 a completed single-step and a software breakpoint. Need to
4182 differentiate between the two, as the latter needs adjusting
4183 but the former does not.
4185 The SIGTRAP can be due to a completed hardware single-step only if
4186 - we didn't insert software single-step breakpoints
4187 - this thread is currently being stepped
4189 If any of these events did not occur, we must have stopped due
4190 to hitting a software breakpoint, and have to back up to the
4193 As a special case, we could have hardware single-stepped a
4194 software breakpoint. In this case (prev_pc == breakpoint_pc),
4195 we also need to back up to the breakpoint address. */
4197 if (thread_has_single_step_breakpoints_set (thread
)
4198 || !currently_stepping (thread
)
4199 || (thread
->stepped_breakpoint
4200 && thread
->prev_pc
== breakpoint_pc
))
4201 regcache_write_pc (regcache
, breakpoint_pc
);
4203 do_cleanups (old_cleanups
);
4208 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4210 for (frame
= get_prev_frame (frame
);
4212 frame
= get_prev_frame (frame
))
4214 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4216 if (get_frame_type (frame
) != INLINE_FRAME
)
4223 /* Auxiliary function that handles syscall entry/return events.
4224 It returns 1 if the inferior should keep going (and GDB
4225 should ignore the event), or 0 if the event deserves to be
4229 handle_syscall_event (struct execution_control_state
*ecs
)
4231 struct regcache
*regcache
;
4234 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4235 context_switch (ecs
->ptid
);
4237 regcache
= get_thread_regcache (ecs
->ptid
);
4238 syscall_number
= ecs
->ws
.value
.syscall_number
;
4239 stop_pc
= regcache_read_pc (regcache
);
4241 if (catch_syscall_enabled () > 0
4242 && catching_syscall_number (syscall_number
) > 0)
4245 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4248 ecs
->event_thread
->control
.stop_bpstat
4249 = bpstat_stop_status (get_regcache_aspace (regcache
),
4250 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4252 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4254 /* Catchpoint hit. */
4259 /* If no catchpoint triggered for this, then keep going. */
4264 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4267 fill_in_stop_func (struct gdbarch
*gdbarch
,
4268 struct execution_control_state
*ecs
)
4270 if (!ecs
->stop_func_filled_in
)
4272 /* Don't care about return value; stop_func_start and stop_func_name
4273 will both be 0 if it doesn't work. */
4274 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4275 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4276 ecs
->stop_func_start
4277 += gdbarch_deprecated_function_start_offset (gdbarch
);
4279 if (gdbarch_skip_entrypoint_p (gdbarch
))
4280 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4281 ecs
->stop_func_start
);
4283 ecs
->stop_func_filled_in
= 1;
4288 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4290 static enum stop_kind
4291 get_inferior_stop_soon (ptid_t ptid
)
4293 struct inferior
*inf
= find_inferior_ptid (ptid
);
4295 gdb_assert (inf
!= NULL
);
4296 return inf
->control
.stop_soon
;
4299 /* Wait for one event. Store the resulting waitstatus in WS, and
4300 return the event ptid. */
4303 wait_one (struct target_waitstatus
*ws
)
4306 ptid_t wait_ptid
= minus_one_ptid
;
4308 overlay_cache_invalid
= 1;
4310 /* Flush target cache before starting to handle each event.
4311 Target was running and cache could be stale. This is just a
4312 heuristic. Running threads may modify target memory, but we
4313 don't get any event. */
4314 target_dcache_invalidate ();
4316 if (deprecated_target_wait_hook
)
4317 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4319 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4322 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4327 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4328 instead of the current thread. */
4329 #define THREAD_STOPPED_BY(REASON) \
4331 thread_stopped_by_ ## REASON (ptid_t ptid) \
4333 struct cleanup *old_chain; \
4336 old_chain = save_inferior_ptid (); \
4337 inferior_ptid = ptid; \
4339 res = target_stopped_by_ ## REASON (); \
4341 do_cleanups (old_chain); \
4346 /* Generate thread_stopped_by_watchpoint. */
4347 THREAD_STOPPED_BY (watchpoint
)
4348 /* Generate thread_stopped_by_sw_breakpoint. */
4349 THREAD_STOPPED_BY (sw_breakpoint
)
4350 /* Generate thread_stopped_by_hw_breakpoint. */
4351 THREAD_STOPPED_BY (hw_breakpoint
)
4353 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4356 switch_to_thread_cleanup (void *ptid_p
)
4358 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4360 switch_to_thread (ptid
);
4363 /* Save the thread's event and stop reason to process it later. */
4366 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4368 struct regcache
*regcache
;
4369 struct address_space
*aspace
;
4375 statstr
= target_waitstatus_to_string (ws
);
4376 fprintf_unfiltered (gdb_stdlog
,
4377 "infrun: saving status %s for %d.%ld.%ld\n",
4379 ptid_get_pid (tp
->ptid
),
4380 ptid_get_lwp (tp
->ptid
),
4381 ptid_get_tid (tp
->ptid
));
4385 /* Record for later. */
4386 tp
->suspend
.waitstatus
= *ws
;
4387 tp
->suspend
.waitstatus_pending_p
= 1;
4389 regcache
= get_thread_regcache (tp
->ptid
);
4390 aspace
= get_regcache_aspace (regcache
);
4392 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4393 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4395 CORE_ADDR pc
= regcache_read_pc (regcache
);
4397 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4399 if (thread_stopped_by_watchpoint (tp
->ptid
))
4401 tp
->suspend
.stop_reason
4402 = TARGET_STOPPED_BY_WATCHPOINT
;
4404 else if (target_supports_stopped_by_sw_breakpoint ()
4405 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4407 tp
->suspend
.stop_reason
4408 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4410 else if (target_supports_stopped_by_hw_breakpoint ()
4411 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4413 tp
->suspend
.stop_reason
4414 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4416 else if (!target_supports_stopped_by_hw_breakpoint ()
4417 && hardware_breakpoint_inserted_here_p (aspace
,
4420 tp
->suspend
.stop_reason
4421 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4423 else if (!target_supports_stopped_by_sw_breakpoint ()
4424 && software_breakpoint_inserted_here_p (aspace
,
4427 tp
->suspend
.stop_reason
4428 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4430 else if (!thread_has_single_step_breakpoints_set (tp
)
4431 && currently_stepping (tp
))
4433 tp
->suspend
.stop_reason
4434 = TARGET_STOPPED_BY_SINGLE_STEP
;
4442 stop_all_threads (void)
4444 /* We may need multiple passes to discover all threads. */
4448 struct cleanup
*old_chain
;
4450 gdb_assert (target_is_non_stop_p ());
4453 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4455 entry_ptid
= inferior_ptid
;
4456 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4458 /* Request threads to stop, and then wait for the stops. Because
4459 threads we already know about can spawn more threads while we're
4460 trying to stop them, and we only learn about new threads when we
4461 update the thread list, do this in a loop, and keep iterating
4462 until two passes find no threads that need to be stopped. */
4463 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4466 fprintf_unfiltered (gdb_stdlog
,
4467 "infrun: stop_all_threads, pass=%d, "
4468 "iterations=%d\n", pass
, iterations
);
4472 struct target_waitstatus ws
;
4474 struct thread_info
*t
;
4476 update_thread_list ();
4478 /* Go through all threads looking for threads that we need
4479 to tell the target to stop. */
4480 ALL_NON_EXITED_THREADS (t
)
4484 /* If already stopping, don't request a stop again.
4485 We just haven't seen the notification yet. */
4486 if (!t
->stop_requested
)
4489 fprintf_unfiltered (gdb_stdlog
,
4490 "infrun: %s executing, "
4492 target_pid_to_str (t
->ptid
));
4493 target_stop (t
->ptid
);
4494 t
->stop_requested
= 1;
4499 fprintf_unfiltered (gdb_stdlog
,
4500 "infrun: %s executing, "
4501 "already stopping\n",
4502 target_pid_to_str (t
->ptid
));
4505 if (t
->stop_requested
)
4511 fprintf_unfiltered (gdb_stdlog
,
4512 "infrun: %s not executing\n",
4513 target_pid_to_str (t
->ptid
));
4515 /* The thread may be not executing, but still be
4516 resumed with a pending status to process. */
4524 /* If we find new threads on the second iteration, restart
4525 over. We want to see two iterations in a row with all
4530 event_ptid
= wait_one (&ws
);
4531 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4533 /* All resumed threads exited. */
4535 else if (ws
.kind
== TARGET_WAITKIND_EXITED
4536 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4540 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4542 fprintf_unfiltered (gdb_stdlog
,
4543 "infrun: %s exited while "
4544 "stopping threads\n",
4545 target_pid_to_str (ptid
));
4550 struct inferior
*inf
;
4552 t
= find_thread_ptid (event_ptid
);
4554 t
= add_thread (event_ptid
);
4556 t
->stop_requested
= 0;
4559 t
->control
.may_range_step
= 0;
4561 /* This may be the first time we see the inferior report
4563 inf
= find_inferior_ptid (event_ptid
);
4564 if (inf
->needs_setup
)
4566 switch_to_thread_no_regs (t
);
4570 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4571 && ws
.value
.sig
== GDB_SIGNAL_0
)
4573 /* We caught the event that we intended to catch, so
4574 there's no event pending. */
4575 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4576 t
->suspend
.waitstatus_pending_p
= 0;
4578 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4580 /* Add it back to the step-over queue. */
4583 fprintf_unfiltered (gdb_stdlog
,
4584 "infrun: displaced-step of %s "
4585 "canceled: adding back to the "
4586 "step-over queue\n",
4587 target_pid_to_str (t
->ptid
));
4589 t
->control
.trap_expected
= 0;
4590 thread_step_over_chain_enqueue (t
);
4595 enum gdb_signal sig
;
4596 struct regcache
*regcache
;
4597 struct address_space
*aspace
;
4603 statstr
= target_waitstatus_to_string (&ws
);
4604 fprintf_unfiltered (gdb_stdlog
,
4605 "infrun: target_wait %s, saving "
4606 "status for %d.%ld.%ld\n",
4608 ptid_get_pid (t
->ptid
),
4609 ptid_get_lwp (t
->ptid
),
4610 ptid_get_tid (t
->ptid
));
4614 /* Record for later. */
4615 save_waitstatus (t
, &ws
);
4617 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4618 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4620 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4622 /* Add it back to the step-over queue. */
4623 t
->control
.trap_expected
= 0;
4624 thread_step_over_chain_enqueue (t
);
4627 regcache
= get_thread_regcache (t
->ptid
);
4628 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4632 fprintf_unfiltered (gdb_stdlog
,
4633 "infrun: saved stop_pc=%s for %s "
4634 "(currently_stepping=%d)\n",
4635 paddress (target_gdbarch (),
4636 t
->suspend
.stop_pc
),
4637 target_pid_to_str (t
->ptid
),
4638 currently_stepping (t
));
4645 do_cleanups (old_chain
);
4648 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4651 /* Given an execution control state that has been freshly filled in by
4652 an event from the inferior, figure out what it means and take
4655 The alternatives are:
4657 1) stop_waiting and return; to really stop and return to the
4660 2) keep_going and return; to wait for the next event (set
4661 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4665 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4667 enum stop_kind stop_soon
;
4669 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4671 /* We had an event in the inferior, but we are not interested in
4672 handling it at this level. The lower layers have already
4673 done what needs to be done, if anything.
4675 One of the possible circumstances for this is when the
4676 inferior produces output for the console. The inferior has
4677 not stopped, and we are ignoring the event. Another possible
4678 circumstance is any event which the lower level knows will be
4679 reported multiple times without an intervening resume. */
4681 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4682 prepare_to_wait (ecs
);
4686 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4687 && target_can_async_p () && !sync_execution
)
4689 /* There were no unwaited-for children left in the target, but,
4690 we're not synchronously waiting for events either. Just
4691 ignore. Otherwise, if we were running a synchronous
4692 execution command, we need to cancel it and give the user
4693 back the terminal. */
4695 fprintf_unfiltered (gdb_stdlog
,
4696 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
4697 prepare_to_wait (ecs
);
4701 /* Cache the last pid/waitstatus. */
4702 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4704 /* Always clear state belonging to the previous time we stopped. */
4705 stop_stack_dummy
= STOP_NONE
;
4707 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4709 /* No unwaited-for children left. IOW, all resumed children
4712 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4714 stop_print_frame
= 0;
4719 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4720 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4722 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4723 /* If it's a new thread, add it to the thread database. */
4724 if (ecs
->event_thread
== NULL
)
4725 ecs
->event_thread
= add_thread (ecs
->ptid
);
4727 /* Disable range stepping. If the next step request could use a
4728 range, this will be end up re-enabled then. */
4729 ecs
->event_thread
->control
.may_range_step
= 0;
4732 /* Dependent on valid ECS->EVENT_THREAD. */
4733 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4735 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4736 reinit_frame_cache ();
4738 breakpoint_retire_moribund ();
4740 /* First, distinguish signals caused by the debugger from signals
4741 that have to do with the program's own actions. Note that
4742 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4743 on the operating system version. Here we detect when a SIGILL or
4744 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4745 something similar for SIGSEGV, since a SIGSEGV will be generated
4746 when we're trying to execute a breakpoint instruction on a
4747 non-executable stack. This happens for call dummy breakpoints
4748 for architectures like SPARC that place call dummies on the
4750 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4751 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4752 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4753 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4755 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4757 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
4758 regcache_read_pc (regcache
)))
4761 fprintf_unfiltered (gdb_stdlog
,
4762 "infrun: Treating signal as SIGTRAP\n");
4763 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4767 /* Mark the non-executing threads accordingly. In all-stop, all
4768 threads of all processes are stopped when we get any event
4769 reported. In non-stop mode, only the event thread stops. */
4773 if (!target_is_non_stop_p ())
4774 mark_ptid
= minus_one_ptid
;
4775 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4776 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4778 /* If we're handling a process exit in non-stop mode, even
4779 though threads haven't been deleted yet, one would think
4780 that there is nothing to do, as threads of the dead process
4781 will be soon deleted, and threads of any other process were
4782 left running. However, on some targets, threads survive a
4783 process exit event. E.g., for the "checkpoint" command,
4784 when the current checkpoint/fork exits, linux-fork.c
4785 automatically switches to another fork from within
4786 target_mourn_inferior, by associating the same
4787 inferior/thread to another fork. We haven't mourned yet at
4788 this point, but we must mark any threads left in the
4789 process as not-executing so that finish_thread_state marks
4790 them stopped (in the user's perspective) if/when we present
4791 the stop to the user. */
4792 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4795 mark_ptid
= ecs
->ptid
;
4797 set_executing (mark_ptid
, 0);
4799 /* Likewise the resumed flag. */
4800 set_resumed (mark_ptid
, 0);
4803 switch (ecs
->ws
.kind
)
4805 case TARGET_WAITKIND_LOADED
:
4807 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4808 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4809 context_switch (ecs
->ptid
);
4810 /* Ignore gracefully during startup of the inferior, as it might
4811 be the shell which has just loaded some objects, otherwise
4812 add the symbols for the newly loaded objects. Also ignore at
4813 the beginning of an attach or remote session; we will query
4814 the full list of libraries once the connection is
4817 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4818 if (stop_soon
== NO_STOP_QUIETLY
)
4820 struct regcache
*regcache
;
4822 regcache
= get_thread_regcache (ecs
->ptid
);
4824 handle_solib_event ();
4826 ecs
->event_thread
->control
.stop_bpstat
4827 = bpstat_stop_status (get_regcache_aspace (regcache
),
4828 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4830 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4832 /* A catchpoint triggered. */
4833 process_event_stop_test (ecs
);
4837 /* If requested, stop when the dynamic linker notifies
4838 gdb of events. This allows the user to get control
4839 and place breakpoints in initializer routines for
4840 dynamically loaded objects (among other things). */
4841 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4842 if (stop_on_solib_events
)
4844 /* Make sure we print "Stopped due to solib-event" in
4846 stop_print_frame
= 1;
4853 /* If we are skipping through a shell, or through shared library
4854 loading that we aren't interested in, resume the program. If
4855 we're running the program normally, also resume. */
4856 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
4858 /* Loading of shared libraries might have changed breakpoint
4859 addresses. Make sure new breakpoints are inserted. */
4860 if (stop_soon
== NO_STOP_QUIETLY
)
4861 insert_breakpoints ();
4862 resume (GDB_SIGNAL_0
);
4863 prepare_to_wait (ecs
);
4867 /* But stop if we're attaching or setting up a remote
4869 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4870 || stop_soon
== STOP_QUIETLY_REMOTE
)
4873 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4878 internal_error (__FILE__
, __LINE__
,
4879 _("unhandled stop_soon: %d"), (int) stop_soon
);
4881 case TARGET_WAITKIND_SPURIOUS
:
4883 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
4884 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4885 context_switch (ecs
->ptid
);
4886 resume (GDB_SIGNAL_0
);
4887 prepare_to_wait (ecs
);
4890 case TARGET_WAITKIND_EXITED
:
4891 case TARGET_WAITKIND_SIGNALLED
:
4894 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4895 fprintf_unfiltered (gdb_stdlog
,
4896 "infrun: TARGET_WAITKIND_EXITED\n");
4898 fprintf_unfiltered (gdb_stdlog
,
4899 "infrun: TARGET_WAITKIND_SIGNALLED\n");
4902 inferior_ptid
= ecs
->ptid
;
4903 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
4904 set_current_program_space (current_inferior ()->pspace
);
4905 handle_vfork_child_exec_or_exit (0);
4906 target_terminal_ours (); /* Must do this before mourn anyway. */
4908 /* Clearing any previous state of convenience variables. */
4909 clear_exit_convenience_vars ();
4911 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4913 /* Record the exit code in the convenience variable $_exitcode, so
4914 that the user can inspect this again later. */
4915 set_internalvar_integer (lookup_internalvar ("_exitcode"),
4916 (LONGEST
) ecs
->ws
.value
.integer
);
4918 /* Also record this in the inferior itself. */
4919 current_inferior ()->has_exit_code
= 1;
4920 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
4922 /* Support the --return-child-result option. */
4923 return_child_result_value
= ecs
->ws
.value
.integer
;
4925 observer_notify_exited (ecs
->ws
.value
.integer
);
4929 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4930 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4932 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
4934 /* Set the value of the internal variable $_exitsignal,
4935 which holds the signal uncaught by the inferior. */
4936 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
4937 gdbarch_gdb_signal_to_target (gdbarch
,
4938 ecs
->ws
.value
.sig
));
4942 /* We don't have access to the target's method used for
4943 converting between signal numbers (GDB's internal
4944 representation <-> target's representation).
4945 Therefore, we cannot do a good job at displaying this
4946 information to the user. It's better to just warn
4947 her about it (if infrun debugging is enabled), and
4950 fprintf_filtered (gdb_stdlog
, _("\
4951 Cannot fill $_exitsignal with the correct signal number.\n"));
4954 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
4957 gdb_flush (gdb_stdout
);
4958 target_mourn_inferior ();
4959 stop_print_frame
= 0;
4963 /* The following are the only cases in which we keep going;
4964 the above cases end in a continue or goto. */
4965 case TARGET_WAITKIND_FORKED
:
4966 case TARGET_WAITKIND_VFORKED
:
4969 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
4970 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
4972 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
4975 /* Check whether the inferior is displaced stepping. */
4977 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4978 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4980 /* If checking displaced stepping is supported, and thread
4981 ecs->ptid is displaced stepping. */
4982 if (displaced_step_in_progress_thread (ecs
->ptid
))
4984 struct inferior
*parent_inf
4985 = find_inferior_ptid (ecs
->ptid
);
4986 struct regcache
*child_regcache
;
4987 CORE_ADDR parent_pc
;
4989 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
4990 indicating that the displaced stepping of syscall instruction
4991 has been done. Perform cleanup for parent process here. Note
4992 that this operation also cleans up the child process for vfork,
4993 because their pages are shared. */
4994 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
4995 /* Start a new step-over in another thread if there's one
4999 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5001 struct displaced_step_inferior_state
*displaced
5002 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
5004 /* Restore scratch pad for child process. */
5005 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
5008 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5009 the child's PC is also within the scratchpad. Set the child's PC
5010 to the parent's PC value, which has already been fixed up.
5011 FIXME: we use the parent's aspace here, although we're touching
5012 the child, because the child hasn't been added to the inferior
5013 list yet at this point. */
5016 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
5018 parent_inf
->aspace
);
5019 /* Read PC value of parent process. */
5020 parent_pc
= regcache_read_pc (regcache
);
5022 if (debug_displaced
)
5023 fprintf_unfiltered (gdb_stdlog
,
5024 "displaced: write child pc from %s to %s\n",
5026 regcache_read_pc (child_regcache
)),
5027 paddress (gdbarch
, parent_pc
));
5029 regcache_write_pc (child_regcache
, parent_pc
);
5033 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5034 context_switch (ecs
->ptid
);
5036 /* Immediately detach breakpoints from the child before there's
5037 any chance of letting the user delete breakpoints from the
5038 breakpoint lists. If we don't do this early, it's easy to
5039 leave left over traps in the child, vis: "break foo; catch
5040 fork; c; <fork>; del; c; <child calls foo>". We only follow
5041 the fork on the last `continue', and by that time the
5042 breakpoint at "foo" is long gone from the breakpoint table.
5043 If we vforked, then we don't need to unpatch here, since both
5044 parent and child are sharing the same memory pages; we'll
5045 need to unpatch at follow/detach time instead to be certain
5046 that new breakpoints added between catchpoint hit time and
5047 vfork follow are detached. */
5048 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5050 /* This won't actually modify the breakpoint list, but will
5051 physically remove the breakpoints from the child. */
5052 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5055 delete_just_stopped_threads_single_step_breakpoints ();
5057 /* In case the event is caught by a catchpoint, remember that
5058 the event is to be followed at the next resume of the thread,
5059 and not immediately. */
5060 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5062 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5064 ecs
->event_thread
->control
.stop_bpstat
5065 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5066 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5068 /* If no catchpoint triggered for this, then keep going. Note
5069 that we're interested in knowing the bpstat actually causes a
5070 stop, not just if it may explain the signal. Software
5071 watchpoints, for example, always appear in the bpstat. */
5072 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5078 = (follow_fork_mode_string
== follow_fork_mode_child
);
5080 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5082 should_resume
= follow_fork ();
5085 child
= ecs
->ws
.value
.related_pid
;
5087 /* In non-stop mode, also resume the other branch. */
5088 if (!detach_fork
&& (non_stop
5089 || (sched_multi
&& target_is_non_stop_p ())))
5092 switch_to_thread (parent
);
5094 switch_to_thread (child
);
5096 ecs
->event_thread
= inferior_thread ();
5097 ecs
->ptid
= inferior_ptid
;
5102 switch_to_thread (child
);
5104 switch_to_thread (parent
);
5106 ecs
->event_thread
= inferior_thread ();
5107 ecs
->ptid
= inferior_ptid
;
5115 process_event_stop_test (ecs
);
5118 case TARGET_WAITKIND_VFORK_DONE
:
5119 /* Done with the shared memory region. Re-insert breakpoints in
5120 the parent, and keep going. */
5123 fprintf_unfiltered (gdb_stdlog
,
5124 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5126 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5127 context_switch (ecs
->ptid
);
5129 current_inferior ()->waiting_for_vfork_done
= 0;
5130 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5131 /* This also takes care of reinserting breakpoints in the
5132 previously locked inferior. */
5136 case TARGET_WAITKIND_EXECD
:
5138 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5140 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5141 context_switch (ecs
->ptid
);
5143 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5145 /* Do whatever is necessary to the parent branch of the vfork. */
5146 handle_vfork_child_exec_or_exit (1);
5148 /* This causes the eventpoints and symbol table to be reset.
5149 Must do this now, before trying to determine whether to
5151 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5153 /* In follow_exec we may have deleted the original thread and
5154 created a new one. Make sure that the event thread is the
5155 execd thread for that case (this is a nop otherwise). */
5156 ecs
->event_thread
= inferior_thread ();
5158 ecs
->event_thread
->control
.stop_bpstat
5159 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5160 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5162 /* Note that this may be referenced from inside
5163 bpstat_stop_status above, through inferior_has_execd. */
5164 xfree (ecs
->ws
.value
.execd_pathname
);
5165 ecs
->ws
.value
.execd_pathname
= NULL
;
5167 /* If no catchpoint triggered for this, then keep going. */
5168 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5170 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5174 process_event_stop_test (ecs
);
5177 /* Be careful not to try to gather much state about a thread
5178 that's in a syscall. It's frequently a losing proposition. */
5179 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5181 fprintf_unfiltered (gdb_stdlog
,
5182 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5183 /* Getting the current syscall number. */
5184 if (handle_syscall_event (ecs
) == 0)
5185 process_event_stop_test (ecs
);
5188 /* Before examining the threads further, step this thread to
5189 get it entirely out of the syscall. (We get notice of the
5190 event when the thread is just on the verge of exiting a
5191 syscall. Stepping one instruction seems to get it back
5193 case TARGET_WAITKIND_SYSCALL_RETURN
:
5195 fprintf_unfiltered (gdb_stdlog
,
5196 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5197 if (handle_syscall_event (ecs
) == 0)
5198 process_event_stop_test (ecs
);
5201 case TARGET_WAITKIND_STOPPED
:
5203 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5204 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5205 handle_signal_stop (ecs
);
5208 case TARGET_WAITKIND_NO_HISTORY
:
5210 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5211 /* Reverse execution: target ran out of history info. */
5213 /* Switch to the stopped thread. */
5214 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5215 context_switch (ecs
->ptid
);
5217 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5219 delete_just_stopped_threads_single_step_breakpoints ();
5220 stop_pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
5221 observer_notify_no_history ();
5227 /* A wrapper around handle_inferior_event_1, which also makes sure
5228 that all temporary struct value objects that were created during
5229 the handling of the event get deleted at the end. */
5232 handle_inferior_event (struct execution_control_state
*ecs
)
5234 struct value
*mark
= value_mark ();
5236 handle_inferior_event_1 (ecs
);
5237 /* Purge all temporary values created during the event handling,
5238 as it could be a long time before we return to the command level
5239 where such values would otherwise be purged. */
5240 value_free_to_mark (mark
);
5243 /* Restart threads back to what they were trying to do back when we
5244 paused them for an in-line step-over. The EVENT_THREAD thread is
5248 restart_threads (struct thread_info
*event_thread
)
5250 struct thread_info
*tp
;
5251 struct thread_info
*step_over
= NULL
;
5253 /* In case the instruction just stepped spawned a new thread. */
5254 update_thread_list ();
5256 ALL_NON_EXITED_THREADS (tp
)
5258 if (tp
== event_thread
)
5261 fprintf_unfiltered (gdb_stdlog
,
5262 "infrun: restart threads: "
5263 "[%s] is event thread\n",
5264 target_pid_to_str (tp
->ptid
));
5268 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5271 fprintf_unfiltered (gdb_stdlog
,
5272 "infrun: restart threads: "
5273 "[%s] not meant to be running\n",
5274 target_pid_to_str (tp
->ptid
));
5281 fprintf_unfiltered (gdb_stdlog
,
5282 "infrun: restart threads: [%s] resumed\n",
5283 target_pid_to_str (tp
->ptid
));
5284 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5288 if (thread_is_in_step_over_chain (tp
))
5291 fprintf_unfiltered (gdb_stdlog
,
5292 "infrun: restart threads: "
5293 "[%s] needs step-over\n",
5294 target_pid_to_str (tp
->ptid
));
5295 gdb_assert (!tp
->resumed
);
5300 if (tp
->suspend
.waitstatus_pending_p
)
5303 fprintf_unfiltered (gdb_stdlog
,
5304 "infrun: restart threads: "
5305 "[%s] has pending status\n",
5306 target_pid_to_str (tp
->ptid
));
5311 /* If some thread needs to start a step-over at this point, it
5312 should still be in the step-over queue, and thus skipped
5314 if (thread_still_needs_step_over (tp
))
5316 internal_error (__FILE__
, __LINE__
,
5317 "thread [%s] needs a step-over, but not in "
5318 "step-over queue\n",
5319 target_pid_to_str (tp
->ptid
));
5322 if (currently_stepping (tp
))
5325 fprintf_unfiltered (gdb_stdlog
,
5326 "infrun: restart threads: [%s] was stepping\n",
5327 target_pid_to_str (tp
->ptid
));
5328 keep_going_stepped_thread (tp
);
5332 struct execution_control_state ecss
;
5333 struct execution_control_state
*ecs
= &ecss
;
5336 fprintf_unfiltered (gdb_stdlog
,
5337 "infrun: restart threads: [%s] continuing\n",
5338 target_pid_to_str (tp
->ptid
));
5339 reset_ecs (ecs
, tp
);
5340 switch_to_thread (tp
->ptid
);
5341 keep_going_pass_signal (ecs
);
5346 /* Callback for iterate_over_threads. Find a resumed thread that has
5347 a pending waitstatus. */
5350 resumed_thread_with_pending_status (struct thread_info
*tp
,
5354 && tp
->suspend
.waitstatus_pending_p
);
5357 /* Called when we get an event that may finish an in-line or
5358 out-of-line (displaced stepping) step-over started previously.
5359 Return true if the event is processed and we should go back to the
5360 event loop; false if the caller should continue processing the
5364 finish_step_over (struct execution_control_state
*ecs
)
5366 int had_step_over_info
;
5368 displaced_step_fixup (ecs
->ptid
,
5369 ecs
->event_thread
->suspend
.stop_signal
);
5371 had_step_over_info
= step_over_info_valid_p ();
5373 if (had_step_over_info
)
5375 /* If we're stepping over a breakpoint with all threads locked,
5376 then only the thread that was stepped should be reporting
5378 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5380 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5381 clear_step_over_info ();
5384 if (!target_is_non_stop_p ())
5387 /* Start a new step-over in another thread if there's one that
5391 /* If we were stepping over a breakpoint before, and haven't started
5392 a new in-line step-over sequence, then restart all other threads
5393 (except the event thread). We can't do this in all-stop, as then
5394 e.g., we wouldn't be able to issue any other remote packet until
5395 these other threads stop. */
5396 if (had_step_over_info
&& !step_over_info_valid_p ())
5398 struct thread_info
*pending
;
5400 /* If we only have threads with pending statuses, the restart
5401 below won't restart any thread and so nothing re-inserts the
5402 breakpoint we just stepped over. But we need it inserted
5403 when we later process the pending events, otherwise if
5404 another thread has a pending event for this breakpoint too,
5405 we'd discard its event (because the breakpoint that
5406 originally caused the event was no longer inserted). */
5407 context_switch (ecs
->ptid
);
5408 insert_breakpoints ();
5410 restart_threads (ecs
->event_thread
);
5412 /* If we have events pending, go through handle_inferior_event
5413 again, picking up a pending event at random. This avoids
5414 thread starvation. */
5416 /* But not if we just stepped over a watchpoint in order to let
5417 the instruction execute so we can evaluate its expression.
5418 The set of watchpoints that triggered is recorded in the
5419 breakpoint objects themselves (see bp->watchpoint_triggered).
5420 If we processed another event first, that other event could
5421 clobber this info. */
5422 if (ecs
->event_thread
->stepping_over_watchpoint
)
5425 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5427 if (pending
!= NULL
)
5429 struct thread_info
*tp
= ecs
->event_thread
;
5430 struct regcache
*regcache
;
5434 fprintf_unfiltered (gdb_stdlog
,
5435 "infrun: found resumed threads with "
5436 "pending events, saving status\n");
5439 gdb_assert (pending
!= tp
);
5441 /* Record the event thread's event for later. */
5442 save_waitstatus (tp
, &ecs
->ws
);
5443 /* This was cleared early, by handle_inferior_event. Set it
5444 so this pending event is considered by
5448 gdb_assert (!tp
->executing
);
5450 regcache
= get_thread_regcache (tp
->ptid
);
5451 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5455 fprintf_unfiltered (gdb_stdlog
,
5456 "infrun: saved stop_pc=%s for %s "
5457 "(currently_stepping=%d)\n",
5458 paddress (target_gdbarch (),
5459 tp
->suspend
.stop_pc
),
5460 target_pid_to_str (tp
->ptid
),
5461 currently_stepping (tp
));
5464 /* This in-line step-over finished; clear this so we won't
5465 start a new one. This is what handle_signal_stop would
5466 do, if we returned false. */
5467 tp
->stepping_over_breakpoint
= 0;
5469 /* Wake up the event loop again. */
5470 mark_async_event_handler (infrun_async_inferior_event_token
);
5472 prepare_to_wait (ecs
);
5480 /* Come here when the program has stopped with a signal. */
5483 handle_signal_stop (struct execution_control_state
*ecs
)
5485 struct frame_info
*frame
;
5486 struct gdbarch
*gdbarch
;
5487 int stopped_by_watchpoint
;
5488 enum stop_kind stop_soon
;
5491 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5493 /* Do we need to clean up the state of a thread that has
5494 completed a displaced single-step? (Doing so usually affects
5495 the PC, so do it here, before we set stop_pc.) */
5496 if (finish_step_over (ecs
))
5499 /* If we either finished a single-step or hit a breakpoint, but
5500 the user wanted this thread to be stopped, pretend we got a
5501 SIG0 (generic unsignaled stop). */
5502 if (ecs
->event_thread
->stop_requested
5503 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5504 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5506 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5510 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5511 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5512 struct cleanup
*old_chain
= save_inferior_ptid ();
5514 inferior_ptid
= ecs
->ptid
;
5516 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5517 paddress (gdbarch
, stop_pc
));
5518 if (target_stopped_by_watchpoint ())
5522 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5524 if (target_stopped_data_address (¤t_target
, &addr
))
5525 fprintf_unfiltered (gdb_stdlog
,
5526 "infrun: stopped data address = %s\n",
5527 paddress (gdbarch
, addr
));
5529 fprintf_unfiltered (gdb_stdlog
,
5530 "infrun: (no data address available)\n");
5533 do_cleanups (old_chain
);
5536 /* This is originated from start_remote(), start_inferior() and
5537 shared libraries hook functions. */
5538 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5539 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5541 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5542 context_switch (ecs
->ptid
);
5544 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5545 stop_print_frame
= 1;
5550 /* This originates from attach_command(). We need to overwrite
5551 the stop_signal here, because some kernels don't ignore a
5552 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5553 See more comments in inferior.h. On the other hand, if we
5554 get a non-SIGSTOP, report it to the user - assume the backend
5555 will handle the SIGSTOP if it should show up later.
5557 Also consider that the attach is complete when we see a
5558 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5559 target extended-remote report it instead of a SIGSTOP
5560 (e.g. gdbserver). We already rely on SIGTRAP being our
5561 signal, so this is no exception.
5563 Also consider that the attach is complete when we see a
5564 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5565 the target to stop all threads of the inferior, in case the
5566 low level attach operation doesn't stop them implicitly. If
5567 they weren't stopped implicitly, then the stub will report a
5568 GDB_SIGNAL_0, meaning: stopped for no particular reason
5569 other than GDB's request. */
5570 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5571 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5572 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5573 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5575 stop_print_frame
= 1;
5577 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5581 /* See if something interesting happened to the non-current thread. If
5582 so, then switch to that thread. */
5583 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5586 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5588 context_switch (ecs
->ptid
);
5590 if (deprecated_context_hook
)
5591 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
5594 /* At this point, get hold of the now-current thread's frame. */
5595 frame
= get_current_frame ();
5596 gdbarch
= get_frame_arch (frame
);
5598 /* Pull the single step breakpoints out of the target. */
5599 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5601 struct regcache
*regcache
;
5602 struct address_space
*aspace
;
5605 regcache
= get_thread_regcache (ecs
->ptid
);
5606 aspace
= get_regcache_aspace (regcache
);
5607 pc
= regcache_read_pc (regcache
);
5609 /* However, before doing so, if this single-step breakpoint was
5610 actually for another thread, set this thread up for moving
5612 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5615 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5619 fprintf_unfiltered (gdb_stdlog
,
5620 "infrun: [%s] hit another thread's "
5621 "single-step breakpoint\n",
5622 target_pid_to_str (ecs
->ptid
));
5624 ecs
->hit_singlestep_breakpoint
= 1;
5631 fprintf_unfiltered (gdb_stdlog
,
5632 "infrun: [%s] hit its "
5633 "single-step breakpoint\n",
5634 target_pid_to_str (ecs
->ptid
));
5638 delete_just_stopped_threads_single_step_breakpoints ();
5640 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5641 && ecs
->event_thread
->control
.trap_expected
5642 && ecs
->event_thread
->stepping_over_watchpoint
)
5643 stopped_by_watchpoint
= 0;
5645 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5647 /* If necessary, step over this watchpoint. We'll be back to display
5649 if (stopped_by_watchpoint
5650 && (target_have_steppable_watchpoint
5651 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5653 /* At this point, we are stopped at an instruction which has
5654 attempted to write to a piece of memory under control of
5655 a watchpoint. The instruction hasn't actually executed
5656 yet. If we were to evaluate the watchpoint expression
5657 now, we would get the old value, and therefore no change
5658 would seem to have occurred.
5660 In order to make watchpoints work `right', we really need
5661 to complete the memory write, and then evaluate the
5662 watchpoint expression. We do this by single-stepping the
5665 It may not be necessary to disable the watchpoint to step over
5666 it. For example, the PA can (with some kernel cooperation)
5667 single step over a watchpoint without disabling the watchpoint.
5669 It is far more common to need to disable a watchpoint to step
5670 the inferior over it. If we have non-steppable watchpoints,
5671 we must disable the current watchpoint; it's simplest to
5672 disable all watchpoints.
5674 Any breakpoint at PC must also be stepped over -- if there's
5675 one, it will have already triggered before the watchpoint
5676 triggered, and we either already reported it to the user, or
5677 it didn't cause a stop and we called keep_going. In either
5678 case, if there was a breakpoint at PC, we must be trying to
5680 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5685 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5686 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5687 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5688 ecs
->event_thread
->control
.stop_step
= 0;
5689 stop_print_frame
= 1;
5690 stopped_by_random_signal
= 0;
5692 /* Hide inlined functions starting here, unless we just performed stepi or
5693 nexti. After stepi and nexti, always show the innermost frame (not any
5694 inline function call sites). */
5695 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5697 struct address_space
*aspace
=
5698 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
5700 /* skip_inline_frames is expensive, so we avoid it if we can
5701 determine that the address is one where functions cannot have
5702 been inlined. This improves performance with inferiors that
5703 load a lot of shared libraries, because the solib event
5704 breakpoint is defined as the address of a function (i.e. not
5705 inline). Note that we have to check the previous PC as well
5706 as the current one to catch cases when we have just
5707 single-stepped off a breakpoint prior to reinstating it.
5708 Note that we're assuming that the code we single-step to is
5709 not inline, but that's not definitive: there's nothing
5710 preventing the event breakpoint function from containing
5711 inlined code, and the single-step ending up there. If the
5712 user had set a breakpoint on that inlined code, the missing
5713 skip_inline_frames call would break things. Fortunately
5714 that's an extremely unlikely scenario. */
5715 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5716 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5717 && ecs
->event_thread
->control
.trap_expected
5718 && pc_at_non_inline_function (aspace
,
5719 ecs
->event_thread
->prev_pc
,
5722 skip_inline_frames (ecs
->ptid
);
5724 /* Re-fetch current thread's frame in case that invalidated
5726 frame
= get_current_frame ();
5727 gdbarch
= get_frame_arch (frame
);
5731 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5732 && ecs
->event_thread
->control
.trap_expected
5733 && gdbarch_single_step_through_delay_p (gdbarch
)
5734 && currently_stepping (ecs
->event_thread
))
5736 /* We're trying to step off a breakpoint. Turns out that we're
5737 also on an instruction that needs to be stepped multiple
5738 times before it's been fully executing. E.g., architectures
5739 with a delay slot. It needs to be stepped twice, once for
5740 the instruction and once for the delay slot. */
5741 int step_through_delay
5742 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5744 if (debug_infrun
&& step_through_delay
)
5745 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5746 if (ecs
->event_thread
->control
.step_range_end
== 0
5747 && step_through_delay
)
5749 /* The user issued a continue when stopped at a breakpoint.
5750 Set up for another trap and get out of here. */
5751 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5755 else if (step_through_delay
)
5757 /* The user issued a step when stopped at a breakpoint.
5758 Maybe we should stop, maybe we should not - the delay
5759 slot *might* correspond to a line of source. In any
5760 case, don't decide that here, just set
5761 ecs->stepping_over_breakpoint, making sure we
5762 single-step again before breakpoints are re-inserted. */
5763 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5767 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5768 handles this event. */
5769 ecs
->event_thread
->control
.stop_bpstat
5770 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5771 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5773 /* Following in case break condition called a
5775 stop_print_frame
= 1;
5777 /* This is where we handle "moribund" watchpoints. Unlike
5778 software breakpoints traps, hardware watchpoint traps are
5779 always distinguishable from random traps. If no high-level
5780 watchpoint is associated with the reported stop data address
5781 anymore, then the bpstat does not explain the signal ---
5782 simply make sure to ignore it if `stopped_by_watchpoint' is
5786 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5787 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5789 && stopped_by_watchpoint
)
5790 fprintf_unfiltered (gdb_stdlog
,
5791 "infrun: no user watchpoint explains "
5792 "watchpoint SIGTRAP, ignoring\n");
5794 /* NOTE: cagney/2003-03-29: These checks for a random signal
5795 at one stage in the past included checks for an inferior
5796 function call's call dummy's return breakpoint. The original
5797 comment, that went with the test, read:
5799 ``End of a stack dummy. Some systems (e.g. Sony news) give
5800 another signal besides SIGTRAP, so check here as well as
5803 If someone ever tries to get call dummys on a
5804 non-executable stack to work (where the target would stop
5805 with something like a SIGSEGV), then those tests might need
5806 to be re-instated. Given, however, that the tests were only
5807 enabled when momentary breakpoints were not being used, I
5808 suspect that it won't be the case.
5810 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5811 be necessary for call dummies on a non-executable stack on
5814 /* See if the breakpoints module can explain the signal. */
5816 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5817 ecs
->event_thread
->suspend
.stop_signal
);
5819 /* Maybe this was a trap for a software breakpoint that has since
5821 if (random_signal
&& target_stopped_by_sw_breakpoint ())
5823 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
5825 struct regcache
*regcache
;
5828 /* Re-adjust PC to what the program would see if GDB was not
5830 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
5831 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
5834 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
5836 if (record_full_is_used ())
5837 record_full_gdb_operation_disable_set ();
5839 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
5841 do_cleanups (old_cleanups
);
5846 /* A delayed software breakpoint event. Ignore the trap. */
5848 fprintf_unfiltered (gdb_stdlog
,
5849 "infrun: delayed software breakpoint "
5850 "trap, ignoring\n");
5855 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
5856 has since been removed. */
5857 if (random_signal
&& target_stopped_by_hw_breakpoint ())
5859 /* A delayed hardware breakpoint event. Ignore the trap. */
5861 fprintf_unfiltered (gdb_stdlog
,
5862 "infrun: delayed hardware breakpoint/watchpoint "
5863 "trap, ignoring\n");
5867 /* If not, perhaps stepping/nexting can. */
5869 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5870 && currently_stepping (ecs
->event_thread
));
5872 /* Perhaps the thread hit a single-step breakpoint of _another_
5873 thread. Single-step breakpoints are transparent to the
5874 breakpoints module. */
5876 random_signal
= !ecs
->hit_singlestep_breakpoint
;
5878 /* No? Perhaps we got a moribund watchpoint. */
5880 random_signal
= !stopped_by_watchpoint
;
5882 /* For the program's own signals, act according to
5883 the signal handling tables. */
5887 /* Signal not for debugging purposes. */
5888 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
5889 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
5892 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
5893 gdb_signal_to_symbol_string (stop_signal
));
5895 stopped_by_random_signal
= 1;
5897 /* Always stop on signals if we're either just gaining control
5898 of the program, or the user explicitly requested this thread
5899 to remain stopped. */
5900 if (stop_soon
!= NO_STOP_QUIETLY
5901 || ecs
->event_thread
->stop_requested
5903 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
5909 /* Notify observers the signal has "handle print" set. Note we
5910 returned early above if stopping; normal_stop handles the
5911 printing in that case. */
5912 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
5914 /* The signal table tells us to print about this signal. */
5915 target_terminal_ours_for_output ();
5916 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
5917 target_terminal_inferior ();
5920 /* Clear the signal if it should not be passed. */
5921 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
5922 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5924 if (ecs
->event_thread
->prev_pc
== stop_pc
5925 && ecs
->event_thread
->control
.trap_expected
5926 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5930 /* We were just starting a new sequence, attempting to
5931 single-step off of a breakpoint and expecting a SIGTRAP.
5932 Instead this signal arrives. This signal will take us out
5933 of the stepping range so GDB needs to remember to, when
5934 the signal handler returns, resume stepping off that
5936 /* To simplify things, "continue" is forced to use the same
5937 code paths as single-step - set a breakpoint at the
5938 signal return address and then, once hit, step off that
5941 fprintf_unfiltered (gdb_stdlog
,
5942 "infrun: signal arrived while stepping over "
5945 was_in_line
= step_over_info_valid_p ();
5946 clear_step_over_info ();
5947 insert_hp_step_resume_breakpoint_at_frame (frame
);
5948 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5949 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5950 ecs
->event_thread
->control
.trap_expected
= 0;
5952 if (target_is_non_stop_p ())
5954 /* Either "set non-stop" is "on", or the target is
5955 always in non-stop mode. In this case, we have a bit
5956 more work to do. Resume the current thread, and if
5957 we had paused all threads, restart them while the
5958 signal handler runs. */
5963 restart_threads (ecs
->event_thread
);
5965 else if (debug_infrun
)
5967 fprintf_unfiltered (gdb_stdlog
,
5968 "infrun: no need to restart threads\n");
5973 /* If we were nexting/stepping some other thread, switch to
5974 it, so that we don't continue it, losing control. */
5975 if (!switch_back_to_stepped_thread (ecs
))
5980 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
5981 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
5982 || ecs
->event_thread
->control
.step_range_end
== 1)
5983 && frame_id_eq (get_stack_frame_id (frame
),
5984 ecs
->event_thread
->control
.step_stack_frame_id
)
5985 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5987 /* The inferior is about to take a signal that will take it
5988 out of the single step range. Set a breakpoint at the
5989 current PC (which is presumably where the signal handler
5990 will eventually return) and then allow the inferior to
5993 Note that this is only needed for a signal delivered
5994 while in the single-step range. Nested signals aren't a
5995 problem as they eventually all return. */
5997 fprintf_unfiltered (gdb_stdlog
,
5998 "infrun: signal may take us out of "
5999 "single-step range\n");
6001 clear_step_over_info ();
6002 insert_hp_step_resume_breakpoint_at_frame (frame
);
6003 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6004 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6005 ecs
->event_thread
->control
.trap_expected
= 0;
6010 /* Note: step_resume_breakpoint may be non-NULL. This occures
6011 when either there's a nested signal, or when there's a
6012 pending signal enabled just as the signal handler returns
6013 (leaving the inferior at the step-resume-breakpoint without
6014 actually executing it). Either way continue until the
6015 breakpoint is really hit. */
6017 if (!switch_back_to_stepped_thread (ecs
))
6020 fprintf_unfiltered (gdb_stdlog
,
6021 "infrun: random signal, keep going\n");
6028 process_event_stop_test (ecs
);
6031 /* Come here when we've got some debug event / signal we can explain
6032 (IOW, not a random signal), and test whether it should cause a
6033 stop, or whether we should resume the inferior (transparently).
6034 E.g., could be a breakpoint whose condition evaluates false; we
6035 could be still stepping within the line; etc. */
6038 process_event_stop_test (struct execution_control_state
*ecs
)
6040 struct symtab_and_line stop_pc_sal
;
6041 struct frame_info
*frame
;
6042 struct gdbarch
*gdbarch
;
6043 CORE_ADDR jmp_buf_pc
;
6044 struct bpstat_what what
;
6046 /* Handle cases caused by hitting a breakpoint. */
6048 frame
= get_current_frame ();
6049 gdbarch
= get_frame_arch (frame
);
6051 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6053 if (what
.call_dummy
)
6055 stop_stack_dummy
= what
.call_dummy
;
6058 /* A few breakpoint types have callbacks associated (e.g.,
6059 bp_jit_event). Run them now. */
6060 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6062 /* If we hit an internal event that triggers symbol changes, the
6063 current frame will be invalidated within bpstat_what (e.g., if we
6064 hit an internal solib event). Re-fetch it. */
6065 frame
= get_current_frame ();
6066 gdbarch
= get_frame_arch (frame
);
6068 switch (what
.main_action
)
6070 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6071 /* If we hit the breakpoint at longjmp while stepping, we
6072 install a momentary breakpoint at the target of the
6076 fprintf_unfiltered (gdb_stdlog
,
6077 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6079 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6081 if (what
.is_longjmp
)
6083 struct value
*arg_value
;
6085 /* If we set the longjmp breakpoint via a SystemTap probe,
6086 then use it to extract the arguments. The destination PC
6087 is the third argument to the probe. */
6088 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6091 jmp_buf_pc
= value_as_address (arg_value
);
6092 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6094 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6095 || !gdbarch_get_longjmp_target (gdbarch
,
6096 frame
, &jmp_buf_pc
))
6099 fprintf_unfiltered (gdb_stdlog
,
6100 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6101 "(!gdbarch_get_longjmp_target)\n");
6106 /* Insert a breakpoint at resume address. */
6107 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6110 check_exception_resume (ecs
, frame
);
6114 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6116 struct frame_info
*init_frame
;
6118 /* There are several cases to consider.
6120 1. The initiating frame no longer exists. In this case we
6121 must stop, because the exception or longjmp has gone too
6124 2. The initiating frame exists, and is the same as the
6125 current frame. We stop, because the exception or longjmp
6128 3. The initiating frame exists and is different from the
6129 current frame. This means the exception or longjmp has
6130 been caught beneath the initiating frame, so keep going.
6132 4. longjmp breakpoint has been placed just to protect
6133 against stale dummy frames and user is not interested in
6134 stopping around longjmps. */
6137 fprintf_unfiltered (gdb_stdlog
,
6138 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6140 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6142 delete_exception_resume_breakpoint (ecs
->event_thread
);
6144 if (what
.is_longjmp
)
6146 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6148 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6156 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6160 struct frame_id current_id
6161 = get_frame_id (get_current_frame ());
6162 if (frame_id_eq (current_id
,
6163 ecs
->event_thread
->initiating_frame
))
6165 /* Case 2. Fall through. */
6175 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6177 delete_step_resume_breakpoint (ecs
->event_thread
);
6179 end_stepping_range (ecs
);
6183 case BPSTAT_WHAT_SINGLE
:
6185 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6186 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6187 /* Still need to check other stuff, at least the case where we
6188 are stepping and step out of the right range. */
6191 case BPSTAT_WHAT_STEP_RESUME
:
6193 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6195 delete_step_resume_breakpoint (ecs
->event_thread
);
6196 if (ecs
->event_thread
->control
.proceed_to_finish
6197 && execution_direction
== EXEC_REVERSE
)
6199 struct thread_info
*tp
= ecs
->event_thread
;
6201 /* We are finishing a function in reverse, and just hit the
6202 step-resume breakpoint at the start address of the
6203 function, and we're almost there -- just need to back up
6204 by one more single-step, which should take us back to the
6206 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6210 fill_in_stop_func (gdbarch
, ecs
);
6211 if (stop_pc
== ecs
->stop_func_start
6212 && execution_direction
== EXEC_REVERSE
)
6214 /* We are stepping over a function call in reverse, and just
6215 hit the step-resume breakpoint at the start address of
6216 the function. Go back to single-stepping, which should
6217 take us back to the function call. */
6218 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6224 case BPSTAT_WHAT_STOP_NOISY
:
6226 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6227 stop_print_frame
= 1;
6229 /* Assume the thread stopped for a breapoint. We'll still check
6230 whether a/the breakpoint is there when the thread is next
6232 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6237 case BPSTAT_WHAT_STOP_SILENT
:
6239 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6240 stop_print_frame
= 0;
6242 /* Assume the thread stopped for a breapoint. We'll still check
6243 whether a/the breakpoint is there when the thread is next
6245 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6249 case BPSTAT_WHAT_HP_STEP_RESUME
:
6251 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6253 delete_step_resume_breakpoint (ecs
->event_thread
);
6254 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6256 /* Back when the step-resume breakpoint was inserted, we
6257 were trying to single-step off a breakpoint. Go back to
6259 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6260 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6266 case BPSTAT_WHAT_KEEP_CHECKING
:
6270 /* If we stepped a permanent breakpoint and we had a high priority
6271 step-resume breakpoint for the address we stepped, but we didn't
6272 hit it, then we must have stepped into the signal handler. The
6273 step-resume was only necessary to catch the case of _not_
6274 stepping into the handler, so delete it, and fall through to
6275 checking whether the step finished. */
6276 if (ecs
->event_thread
->stepped_breakpoint
)
6278 struct breakpoint
*sr_bp
6279 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6282 && sr_bp
->loc
->permanent
6283 && sr_bp
->type
== bp_hp_step_resume
6284 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6287 fprintf_unfiltered (gdb_stdlog
,
6288 "infrun: stepped permanent breakpoint, stopped in "
6290 delete_step_resume_breakpoint (ecs
->event_thread
);
6291 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6295 /* We come here if we hit a breakpoint but should not stop for it.
6296 Possibly we also were stepping and should stop for that. So fall
6297 through and test for stepping. But, if not stepping, do not
6300 /* In all-stop mode, if we're currently stepping but have stopped in
6301 some other thread, we need to switch back to the stepped thread. */
6302 if (switch_back_to_stepped_thread (ecs
))
6305 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6308 fprintf_unfiltered (gdb_stdlog
,
6309 "infrun: step-resume breakpoint is inserted\n");
6311 /* Having a step-resume breakpoint overrides anything
6312 else having to do with stepping commands until
6313 that breakpoint is reached. */
6318 if (ecs
->event_thread
->control
.step_range_end
== 0)
6321 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6322 /* Likewise if we aren't even stepping. */
6327 /* Re-fetch current thread's frame in case the code above caused
6328 the frame cache to be re-initialized, making our FRAME variable
6329 a dangling pointer. */
6330 frame
= get_current_frame ();
6331 gdbarch
= get_frame_arch (frame
);
6332 fill_in_stop_func (gdbarch
, ecs
);
6334 /* If stepping through a line, keep going if still within it.
6336 Note that step_range_end is the address of the first instruction
6337 beyond the step range, and NOT the address of the last instruction
6340 Note also that during reverse execution, we may be stepping
6341 through a function epilogue and therefore must detect when
6342 the current-frame changes in the middle of a line. */
6344 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6345 && (execution_direction
!= EXEC_REVERSE
6346 || frame_id_eq (get_frame_id (frame
),
6347 ecs
->event_thread
->control
.step_frame_id
)))
6351 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6352 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6353 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6355 /* Tentatively re-enable range stepping; `resume' disables it if
6356 necessary (e.g., if we're stepping over a breakpoint or we
6357 have software watchpoints). */
6358 ecs
->event_thread
->control
.may_range_step
= 1;
6360 /* When stepping backward, stop at beginning of line range
6361 (unless it's the function entry point, in which case
6362 keep going back to the call point). */
6363 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6364 && stop_pc
!= ecs
->stop_func_start
6365 && execution_direction
== EXEC_REVERSE
)
6366 end_stepping_range (ecs
);
6373 /* We stepped out of the stepping range. */
6375 /* If we are stepping at the source level and entered the runtime
6376 loader dynamic symbol resolution code...
6378 EXEC_FORWARD: we keep on single stepping until we exit the run
6379 time loader code and reach the callee's address.
6381 EXEC_REVERSE: we've already executed the callee (backward), and
6382 the runtime loader code is handled just like any other
6383 undebuggable function call. Now we need only keep stepping
6384 backward through the trampoline code, and that's handled further
6385 down, so there is nothing for us to do here. */
6387 if (execution_direction
!= EXEC_REVERSE
6388 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6389 && in_solib_dynsym_resolve_code (stop_pc
))
6391 CORE_ADDR pc_after_resolver
=
6392 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6395 fprintf_unfiltered (gdb_stdlog
,
6396 "infrun: stepped into dynsym resolve code\n");
6398 if (pc_after_resolver
)
6400 /* Set up a step-resume breakpoint at the address
6401 indicated by SKIP_SOLIB_RESOLVER. */
6402 struct symtab_and_line sr_sal
;
6405 sr_sal
.pc
= pc_after_resolver
;
6406 sr_sal
.pspace
= get_frame_program_space (frame
);
6408 insert_step_resume_breakpoint_at_sal (gdbarch
,
6409 sr_sal
, null_frame_id
);
6416 if (ecs
->event_thread
->control
.step_range_end
!= 1
6417 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6418 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6419 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6422 fprintf_unfiltered (gdb_stdlog
,
6423 "infrun: stepped into signal trampoline\n");
6424 /* The inferior, while doing a "step" or "next", has ended up in
6425 a signal trampoline (either by a signal being delivered or by
6426 the signal handler returning). Just single-step until the
6427 inferior leaves the trampoline (either by calling the handler
6433 /* If we're in the return path from a shared library trampoline,
6434 we want to proceed through the trampoline when stepping. */
6435 /* macro/2012-04-25: This needs to come before the subroutine
6436 call check below as on some targets return trampolines look
6437 like subroutine calls (MIPS16 return thunks). */
6438 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6439 stop_pc
, ecs
->stop_func_name
)
6440 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6442 /* Determine where this trampoline returns. */
6443 CORE_ADDR real_stop_pc
;
6445 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6448 fprintf_unfiltered (gdb_stdlog
,
6449 "infrun: stepped into solib return tramp\n");
6451 /* Only proceed through if we know where it's going. */
6454 /* And put the step-breakpoint there and go until there. */
6455 struct symtab_and_line sr_sal
;
6457 init_sal (&sr_sal
); /* initialize to zeroes */
6458 sr_sal
.pc
= real_stop_pc
;
6459 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6460 sr_sal
.pspace
= get_frame_program_space (frame
);
6462 /* Do not specify what the fp should be when we stop since
6463 on some machines the prologue is where the new fp value
6465 insert_step_resume_breakpoint_at_sal (gdbarch
,
6466 sr_sal
, null_frame_id
);
6468 /* Restart without fiddling with the step ranges or
6475 /* Check for subroutine calls. The check for the current frame
6476 equalling the step ID is not necessary - the check of the
6477 previous frame's ID is sufficient - but it is a common case and
6478 cheaper than checking the previous frame's ID.
6480 NOTE: frame_id_eq will never report two invalid frame IDs as
6481 being equal, so to get into this block, both the current and
6482 previous frame must have valid frame IDs. */
6483 /* The outer_frame_id check is a heuristic to detect stepping
6484 through startup code. If we step over an instruction which
6485 sets the stack pointer from an invalid value to a valid value,
6486 we may detect that as a subroutine call from the mythical
6487 "outermost" function. This could be fixed by marking
6488 outermost frames as !stack_p,code_p,special_p. Then the
6489 initial outermost frame, before sp was valid, would
6490 have code_addr == &_start. See the comment in frame_id_eq
6492 if (!frame_id_eq (get_stack_frame_id (frame
),
6493 ecs
->event_thread
->control
.step_stack_frame_id
)
6494 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6495 ecs
->event_thread
->control
.step_stack_frame_id
)
6496 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6498 || (ecs
->event_thread
->control
.step_start_function
6499 != find_pc_function (stop_pc
)))))
6501 CORE_ADDR real_stop_pc
;
6504 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6506 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6508 /* I presume that step_over_calls is only 0 when we're
6509 supposed to be stepping at the assembly language level
6510 ("stepi"). Just stop. */
6511 /* And this works the same backward as frontward. MVS */
6512 end_stepping_range (ecs
);
6516 /* Reverse stepping through solib trampolines. */
6518 if (execution_direction
== EXEC_REVERSE
6519 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6520 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6521 || (ecs
->stop_func_start
== 0
6522 && in_solib_dynsym_resolve_code (stop_pc
))))
6524 /* Any solib trampoline code can be handled in reverse
6525 by simply continuing to single-step. We have already
6526 executed the solib function (backwards), and a few
6527 steps will take us back through the trampoline to the
6533 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6535 /* We're doing a "next".
6537 Normal (forward) execution: set a breakpoint at the
6538 callee's return address (the address at which the caller
6541 Reverse (backward) execution. set the step-resume
6542 breakpoint at the start of the function that we just
6543 stepped into (backwards), and continue to there. When we
6544 get there, we'll need to single-step back to the caller. */
6546 if (execution_direction
== EXEC_REVERSE
)
6548 /* If we're already at the start of the function, we've either
6549 just stepped backward into a single instruction function,
6550 or stepped back out of a signal handler to the first instruction
6551 of the function. Just keep going, which will single-step back
6553 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6555 struct symtab_and_line sr_sal
;
6557 /* Normal function call return (static or dynamic). */
6559 sr_sal
.pc
= ecs
->stop_func_start
;
6560 sr_sal
.pspace
= get_frame_program_space (frame
);
6561 insert_step_resume_breakpoint_at_sal (gdbarch
,
6562 sr_sal
, null_frame_id
);
6566 insert_step_resume_breakpoint_at_caller (frame
);
6572 /* If we are in a function call trampoline (a stub between the
6573 calling routine and the real function), locate the real
6574 function. That's what tells us (a) whether we want to step
6575 into it at all, and (b) what prologue we want to run to the
6576 end of, if we do step into it. */
6577 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6578 if (real_stop_pc
== 0)
6579 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6580 if (real_stop_pc
!= 0)
6581 ecs
->stop_func_start
= real_stop_pc
;
6583 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6585 struct symtab_and_line sr_sal
;
6588 sr_sal
.pc
= ecs
->stop_func_start
;
6589 sr_sal
.pspace
= get_frame_program_space (frame
);
6591 insert_step_resume_breakpoint_at_sal (gdbarch
,
6592 sr_sal
, null_frame_id
);
6597 /* If we have line number information for the function we are
6598 thinking of stepping into and the function isn't on the skip
6601 If there are several symtabs at that PC (e.g. with include
6602 files), just want to know whether *any* of them have line
6603 numbers. find_pc_line handles this. */
6605 struct symtab_and_line tmp_sal
;
6607 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6608 if (tmp_sal
.line
!= 0
6609 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6612 if (execution_direction
== EXEC_REVERSE
)
6613 handle_step_into_function_backward (gdbarch
, ecs
);
6615 handle_step_into_function (gdbarch
, ecs
);
6620 /* If we have no line number and the step-stop-if-no-debug is
6621 set, we stop the step so that the user has a chance to switch
6622 in assembly mode. */
6623 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6624 && step_stop_if_no_debug
)
6626 end_stepping_range (ecs
);
6630 if (execution_direction
== EXEC_REVERSE
)
6632 /* If we're already at the start of the function, we've either just
6633 stepped backward into a single instruction function without line
6634 number info, or stepped back out of a signal handler to the first
6635 instruction of the function without line number info. Just keep
6636 going, which will single-step back to the caller. */
6637 if (ecs
->stop_func_start
!= stop_pc
)
6639 /* Set a breakpoint at callee's start address.
6640 From there we can step once and be back in the caller. */
6641 struct symtab_and_line sr_sal
;
6644 sr_sal
.pc
= ecs
->stop_func_start
;
6645 sr_sal
.pspace
= get_frame_program_space (frame
);
6646 insert_step_resume_breakpoint_at_sal (gdbarch
,
6647 sr_sal
, null_frame_id
);
6651 /* Set a breakpoint at callee's return address (the address
6652 at which the caller will resume). */
6653 insert_step_resume_breakpoint_at_caller (frame
);
6659 /* Reverse stepping through solib trampolines. */
6661 if (execution_direction
== EXEC_REVERSE
6662 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6664 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6665 || (ecs
->stop_func_start
== 0
6666 && in_solib_dynsym_resolve_code (stop_pc
)))
6668 /* Any solib trampoline code can be handled in reverse
6669 by simply continuing to single-step. We have already
6670 executed the solib function (backwards), and a few
6671 steps will take us back through the trampoline to the
6676 else if (in_solib_dynsym_resolve_code (stop_pc
))
6678 /* Stepped backward into the solib dynsym resolver.
6679 Set a breakpoint at its start and continue, then
6680 one more step will take us out. */
6681 struct symtab_and_line sr_sal
;
6684 sr_sal
.pc
= ecs
->stop_func_start
;
6685 sr_sal
.pspace
= get_frame_program_space (frame
);
6686 insert_step_resume_breakpoint_at_sal (gdbarch
,
6687 sr_sal
, null_frame_id
);
6693 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6695 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6696 the trampoline processing logic, however, there are some trampolines
6697 that have no names, so we should do trampoline handling first. */
6698 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6699 && ecs
->stop_func_name
== NULL
6700 && stop_pc_sal
.line
== 0)
6703 fprintf_unfiltered (gdb_stdlog
,
6704 "infrun: stepped into undebuggable function\n");
6706 /* The inferior just stepped into, or returned to, an
6707 undebuggable function (where there is no debugging information
6708 and no line number corresponding to the address where the
6709 inferior stopped). Since we want to skip this kind of code,
6710 we keep going until the inferior returns from this
6711 function - unless the user has asked us not to (via
6712 set step-mode) or we no longer know how to get back
6713 to the call site. */
6714 if (step_stop_if_no_debug
6715 || !frame_id_p (frame_unwind_caller_id (frame
)))
6717 /* If we have no line number and the step-stop-if-no-debug
6718 is set, we stop the step so that the user has a chance to
6719 switch in assembly mode. */
6720 end_stepping_range (ecs
);
6725 /* Set a breakpoint at callee's return address (the address
6726 at which the caller will resume). */
6727 insert_step_resume_breakpoint_at_caller (frame
);
6733 if (ecs
->event_thread
->control
.step_range_end
== 1)
6735 /* It is stepi or nexti. We always want to stop stepping after
6738 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6739 end_stepping_range (ecs
);
6743 if (stop_pc_sal
.line
== 0)
6745 /* We have no line number information. That means to stop
6746 stepping (does this always happen right after one instruction,
6747 when we do "s" in a function with no line numbers,
6748 or can this happen as a result of a return or longjmp?). */
6750 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6751 end_stepping_range (ecs
);
6755 /* Look for "calls" to inlined functions, part one. If the inline
6756 frame machinery detected some skipped call sites, we have entered
6757 a new inline function. */
6759 if (frame_id_eq (get_frame_id (get_current_frame ()),
6760 ecs
->event_thread
->control
.step_frame_id
)
6761 && inline_skipped_frames (ecs
->ptid
))
6763 struct symtab_and_line call_sal
;
6766 fprintf_unfiltered (gdb_stdlog
,
6767 "infrun: stepped into inlined function\n");
6769 find_frame_sal (get_current_frame (), &call_sal
);
6771 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6773 /* For "step", we're going to stop. But if the call site
6774 for this inlined function is on the same source line as
6775 we were previously stepping, go down into the function
6776 first. Otherwise stop at the call site. */
6778 if (call_sal
.line
== ecs
->event_thread
->current_line
6779 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6780 step_into_inline_frame (ecs
->ptid
);
6782 end_stepping_range (ecs
);
6787 /* For "next", we should stop at the call site if it is on a
6788 different source line. Otherwise continue through the
6789 inlined function. */
6790 if (call_sal
.line
== ecs
->event_thread
->current_line
6791 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6794 end_stepping_range (ecs
);
6799 /* Look for "calls" to inlined functions, part two. If we are still
6800 in the same real function we were stepping through, but we have
6801 to go further up to find the exact frame ID, we are stepping
6802 through a more inlined call beyond its call site. */
6804 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6805 && !frame_id_eq (get_frame_id (get_current_frame ()),
6806 ecs
->event_thread
->control
.step_frame_id
)
6807 && stepped_in_from (get_current_frame (),
6808 ecs
->event_thread
->control
.step_frame_id
))
6811 fprintf_unfiltered (gdb_stdlog
,
6812 "infrun: stepping through inlined function\n");
6814 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6817 end_stepping_range (ecs
);
6821 if ((stop_pc
== stop_pc_sal
.pc
)
6822 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6823 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6825 /* We are at the start of a different line. So stop. Note that
6826 we don't stop if we step into the middle of a different line.
6827 That is said to make things like for (;;) statements work
6830 fprintf_unfiltered (gdb_stdlog
,
6831 "infrun: stepped to a different line\n");
6832 end_stepping_range (ecs
);
6836 /* We aren't done stepping.
6838 Optimize by setting the stepping range to the line.
6839 (We might not be in the original line, but if we entered a
6840 new line in mid-statement, we continue stepping. This makes
6841 things like for(;;) statements work better.) */
6843 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
6844 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
6845 ecs
->event_thread
->control
.may_range_step
= 1;
6846 set_step_info (frame
, stop_pc_sal
);
6849 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
6853 /* In all-stop mode, if we're currently stepping but have stopped in
6854 some other thread, we may need to switch back to the stepped
6855 thread. Returns true we set the inferior running, false if we left
6856 it stopped (and the event needs further processing). */
6859 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
6861 if (!target_is_non_stop_p ())
6863 struct thread_info
*tp
;
6864 struct thread_info
*stepping_thread
;
6866 /* If any thread is blocked on some internal breakpoint, and we
6867 simply need to step over that breakpoint to get it going
6868 again, do that first. */
6870 /* However, if we see an event for the stepping thread, then we
6871 know all other threads have been moved past their breakpoints
6872 already. Let the caller check whether the step is finished,
6873 etc., before deciding to move it past a breakpoint. */
6874 if (ecs
->event_thread
->control
.step_range_end
!= 0)
6877 /* Check if the current thread is blocked on an incomplete
6878 step-over, interrupted by a random signal. */
6879 if (ecs
->event_thread
->control
.trap_expected
6880 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6884 fprintf_unfiltered (gdb_stdlog
,
6885 "infrun: need to finish step-over of [%s]\n",
6886 target_pid_to_str (ecs
->event_thread
->ptid
));
6892 /* Check if the current thread is blocked by a single-step
6893 breakpoint of another thread. */
6894 if (ecs
->hit_singlestep_breakpoint
)
6898 fprintf_unfiltered (gdb_stdlog
,
6899 "infrun: need to step [%s] over single-step "
6901 target_pid_to_str (ecs
->ptid
));
6907 /* If this thread needs yet another step-over (e.g., stepping
6908 through a delay slot), do it first before moving on to
6910 if (thread_still_needs_step_over (ecs
->event_thread
))
6914 fprintf_unfiltered (gdb_stdlog
,
6915 "infrun: thread [%s] still needs step-over\n",
6916 target_pid_to_str (ecs
->event_thread
->ptid
));
6922 /* If scheduler locking applies even if not stepping, there's no
6923 need to walk over threads. Above we've checked whether the
6924 current thread is stepping. If some other thread not the
6925 event thread is stepping, then it must be that scheduler
6926 locking is not in effect. */
6927 if (schedlock_applies (ecs
->event_thread
))
6930 /* Otherwise, we no longer expect a trap in the current thread.
6931 Clear the trap_expected flag before switching back -- this is
6932 what keep_going does as well, if we call it. */
6933 ecs
->event_thread
->control
.trap_expected
= 0;
6935 /* Likewise, clear the signal if it should not be passed. */
6936 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6937 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6939 /* Do all pending step-overs before actually proceeding with
6941 if (start_step_over ())
6943 prepare_to_wait (ecs
);
6947 /* Look for the stepping/nexting thread. */
6948 stepping_thread
= NULL
;
6950 ALL_NON_EXITED_THREADS (tp
)
6952 /* Ignore threads of processes the caller is not
6955 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
6958 /* When stepping over a breakpoint, we lock all threads
6959 except the one that needs to move past the breakpoint.
6960 If a non-event thread has this set, the "incomplete
6961 step-over" check above should have caught it earlier. */
6962 if (tp
->control
.trap_expected
)
6964 internal_error (__FILE__
, __LINE__
,
6965 "[%s] has inconsistent state: "
6966 "trap_expected=%d\n",
6967 target_pid_to_str (tp
->ptid
),
6968 tp
->control
.trap_expected
);
6971 /* Did we find the stepping thread? */
6972 if (tp
->control
.step_range_end
)
6974 /* Yep. There should only one though. */
6975 gdb_assert (stepping_thread
== NULL
);
6977 /* The event thread is handled at the top, before we
6979 gdb_assert (tp
!= ecs
->event_thread
);
6981 /* If some thread other than the event thread is
6982 stepping, then scheduler locking can't be in effect,
6983 otherwise we wouldn't have resumed the current event
6984 thread in the first place. */
6985 gdb_assert (!schedlock_applies (tp
));
6987 stepping_thread
= tp
;
6991 if (stepping_thread
!= NULL
)
6994 fprintf_unfiltered (gdb_stdlog
,
6995 "infrun: switching back to stepped thread\n");
6997 if (keep_going_stepped_thread (stepping_thread
))
6999 prepare_to_wait (ecs
);
7008 /* Set a previously stepped thread back to stepping. Returns true on
7009 success, false if the resume is not possible (e.g., the thread
7013 keep_going_stepped_thread (struct thread_info
*tp
)
7015 struct frame_info
*frame
;
7016 struct gdbarch
*gdbarch
;
7017 struct execution_control_state ecss
;
7018 struct execution_control_state
*ecs
= &ecss
;
7020 /* If the stepping thread exited, then don't try to switch back and
7021 resume it, which could fail in several different ways depending
7022 on the target. Instead, just keep going.
7024 We can find a stepping dead thread in the thread list in two
7027 - The target supports thread exit events, and when the target
7028 tries to delete the thread from the thread list, inferior_ptid
7029 pointed at the exiting thread. In such case, calling
7030 delete_thread does not really remove the thread from the list;
7031 instead, the thread is left listed, with 'exited' state.
7033 - The target's debug interface does not support thread exit
7034 events, and so we have no idea whatsoever if the previously
7035 stepping thread is still alive. For that reason, we need to
7036 synchronously query the target now. */
7038 if (is_exited (tp
->ptid
)
7039 || !target_thread_alive (tp
->ptid
))
7042 fprintf_unfiltered (gdb_stdlog
,
7043 "infrun: not resuming previously "
7044 "stepped thread, it has vanished\n");
7046 delete_thread (tp
->ptid
);
7051 fprintf_unfiltered (gdb_stdlog
,
7052 "infrun: resuming previously stepped thread\n");
7054 reset_ecs (ecs
, tp
);
7055 switch_to_thread (tp
->ptid
);
7057 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
7058 frame
= get_current_frame ();
7059 gdbarch
= get_frame_arch (frame
);
7061 /* If the PC of the thread we were trying to single-step has
7062 changed, then that thread has trapped or been signaled, but the
7063 event has not been reported to GDB yet. Re-poll the target
7064 looking for this particular thread's event (i.e. temporarily
7065 enable schedlock) by:
7067 - setting a break at the current PC
7068 - resuming that particular thread, only (by setting trap
7071 This prevents us continuously moving the single-step breakpoint
7072 forward, one instruction at a time, overstepping. */
7074 if (stop_pc
!= tp
->prev_pc
)
7079 fprintf_unfiltered (gdb_stdlog
,
7080 "infrun: expected thread advanced also (%s -> %s)\n",
7081 paddress (target_gdbarch (), tp
->prev_pc
),
7082 paddress (target_gdbarch (), stop_pc
));
7084 /* Clear the info of the previous step-over, as it's no longer
7085 valid (if the thread was trying to step over a breakpoint, it
7086 has already succeeded). It's what keep_going would do too,
7087 if we called it. Do this before trying to insert the sss
7088 breakpoint, otherwise if we were previously trying to step
7089 over this exact address in another thread, the breakpoint is
7091 clear_step_over_info ();
7092 tp
->control
.trap_expected
= 0;
7094 insert_single_step_breakpoint (get_frame_arch (frame
),
7095 get_frame_address_space (frame
),
7099 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7100 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7105 fprintf_unfiltered (gdb_stdlog
,
7106 "infrun: expected thread still hasn't advanced\n");
7108 keep_going_pass_signal (ecs
);
7113 /* Is thread TP in the middle of (software or hardware)
7114 single-stepping? (Note the result of this function must never be
7115 passed directly as target_resume's STEP parameter.) */
7118 currently_stepping (struct thread_info
*tp
)
7120 return ((tp
->control
.step_range_end
7121 && tp
->control
.step_resume_breakpoint
== NULL
)
7122 || tp
->control
.trap_expected
7123 || tp
->stepped_breakpoint
7124 || bpstat_should_step ());
7127 /* Inferior has stepped into a subroutine call with source code that
7128 we should not step over. Do step to the first line of code in
7132 handle_step_into_function (struct gdbarch
*gdbarch
,
7133 struct execution_control_state
*ecs
)
7135 struct compunit_symtab
*cust
;
7136 struct symtab_and_line stop_func_sal
, sr_sal
;
7138 fill_in_stop_func (gdbarch
, ecs
);
7140 cust
= find_pc_compunit_symtab (stop_pc
);
7141 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7142 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7143 ecs
->stop_func_start
);
7145 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7146 /* Use the step_resume_break to step until the end of the prologue,
7147 even if that involves jumps (as it seems to on the vax under
7149 /* If the prologue ends in the middle of a source line, continue to
7150 the end of that source line (if it is still within the function).
7151 Otherwise, just go to end of prologue. */
7152 if (stop_func_sal
.end
7153 && stop_func_sal
.pc
!= ecs
->stop_func_start
7154 && stop_func_sal
.end
< ecs
->stop_func_end
)
7155 ecs
->stop_func_start
= stop_func_sal
.end
;
7157 /* Architectures which require breakpoint adjustment might not be able
7158 to place a breakpoint at the computed address. If so, the test
7159 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7160 ecs->stop_func_start to an address at which a breakpoint may be
7161 legitimately placed.
7163 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7164 made, GDB will enter an infinite loop when stepping through
7165 optimized code consisting of VLIW instructions which contain
7166 subinstructions corresponding to different source lines. On
7167 FR-V, it's not permitted to place a breakpoint on any but the
7168 first subinstruction of a VLIW instruction. When a breakpoint is
7169 set, GDB will adjust the breakpoint address to the beginning of
7170 the VLIW instruction. Thus, we need to make the corresponding
7171 adjustment here when computing the stop address. */
7173 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7175 ecs
->stop_func_start
7176 = gdbarch_adjust_breakpoint_address (gdbarch
,
7177 ecs
->stop_func_start
);
7180 if (ecs
->stop_func_start
== stop_pc
)
7182 /* We are already there: stop now. */
7183 end_stepping_range (ecs
);
7188 /* Put the step-breakpoint there and go until there. */
7189 init_sal (&sr_sal
); /* initialize to zeroes */
7190 sr_sal
.pc
= ecs
->stop_func_start
;
7191 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7192 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7194 /* Do not specify what the fp should be when we stop since on
7195 some machines the prologue is where the new fp value is
7197 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7199 /* And make sure stepping stops right away then. */
7200 ecs
->event_thread
->control
.step_range_end
7201 = ecs
->event_thread
->control
.step_range_start
;
7206 /* Inferior has stepped backward into a subroutine call with source
7207 code that we should not step over. Do step to the beginning of the
7208 last line of code in it. */
7211 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7212 struct execution_control_state
*ecs
)
7214 struct compunit_symtab
*cust
;
7215 struct symtab_and_line stop_func_sal
;
7217 fill_in_stop_func (gdbarch
, ecs
);
7219 cust
= find_pc_compunit_symtab (stop_pc
);
7220 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7221 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7222 ecs
->stop_func_start
);
7224 stop_func_sal
= find_pc_line (stop_pc
, 0);
7226 /* OK, we're just going to keep stepping here. */
7227 if (stop_func_sal
.pc
== stop_pc
)
7229 /* We're there already. Just stop stepping now. */
7230 end_stepping_range (ecs
);
7234 /* Else just reset the step range and keep going.
7235 No step-resume breakpoint, they don't work for
7236 epilogues, which can have multiple entry paths. */
7237 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7238 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7244 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7245 This is used to both functions and to skip over code. */
7248 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7249 struct symtab_and_line sr_sal
,
7250 struct frame_id sr_id
,
7251 enum bptype sr_type
)
7253 /* There should never be more than one step-resume or longjmp-resume
7254 breakpoint per thread, so we should never be setting a new
7255 step_resume_breakpoint when one is already active. */
7256 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7257 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7260 fprintf_unfiltered (gdb_stdlog
,
7261 "infrun: inserting step-resume breakpoint at %s\n",
7262 paddress (gdbarch
, sr_sal
.pc
));
7264 inferior_thread ()->control
.step_resume_breakpoint
7265 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
7269 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7270 struct symtab_and_line sr_sal
,
7271 struct frame_id sr_id
)
7273 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7278 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7279 This is used to skip a potential signal handler.
7281 This is called with the interrupted function's frame. The signal
7282 handler, when it returns, will resume the interrupted function at
7286 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7288 struct symtab_and_line sr_sal
;
7289 struct gdbarch
*gdbarch
;
7291 gdb_assert (return_frame
!= NULL
);
7292 init_sal (&sr_sal
); /* initialize to zeros */
7294 gdbarch
= get_frame_arch (return_frame
);
7295 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7296 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7297 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7299 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7300 get_stack_frame_id (return_frame
),
7304 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7305 is used to skip a function after stepping into it (for "next" or if
7306 the called function has no debugging information).
7308 The current function has almost always been reached by single
7309 stepping a call or return instruction. NEXT_FRAME belongs to the
7310 current function, and the breakpoint will be set at the caller's
7313 This is a separate function rather than reusing
7314 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7315 get_prev_frame, which may stop prematurely (see the implementation
7316 of frame_unwind_caller_id for an example). */
7319 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7321 struct symtab_and_line sr_sal
;
7322 struct gdbarch
*gdbarch
;
7324 /* We shouldn't have gotten here if we don't know where the call site
7326 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7328 init_sal (&sr_sal
); /* initialize to zeros */
7330 gdbarch
= frame_unwind_caller_arch (next_frame
);
7331 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7332 frame_unwind_caller_pc (next_frame
));
7333 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7334 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7336 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7337 frame_unwind_caller_id (next_frame
));
7340 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7341 new breakpoint at the target of a jmp_buf. The handling of
7342 longjmp-resume uses the same mechanisms used for handling
7343 "step-resume" breakpoints. */
7346 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7348 /* There should never be more than one longjmp-resume breakpoint per
7349 thread, so we should never be setting a new
7350 longjmp_resume_breakpoint when one is already active. */
7351 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7354 fprintf_unfiltered (gdb_stdlog
,
7355 "infrun: inserting longjmp-resume breakpoint at %s\n",
7356 paddress (gdbarch
, pc
));
7358 inferior_thread ()->control
.exception_resume_breakpoint
=
7359 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
7362 /* Insert an exception resume breakpoint. TP is the thread throwing
7363 the exception. The block B is the block of the unwinder debug hook
7364 function. FRAME is the frame corresponding to the call to this
7365 function. SYM is the symbol of the function argument holding the
7366 target PC of the exception. */
7369 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7370 const struct block
*b
,
7371 struct frame_info
*frame
,
7376 struct block_symbol vsym
;
7377 struct value
*value
;
7379 struct breakpoint
*bp
;
7381 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
7382 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7383 /* If the value was optimized out, revert to the old behavior. */
7384 if (! value_optimized_out (value
))
7386 handler
= value_as_address (value
);
7389 fprintf_unfiltered (gdb_stdlog
,
7390 "infrun: exception resume at %lx\n",
7391 (unsigned long) handler
);
7393 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7394 handler
, bp_exception_resume
);
7396 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7399 bp
->thread
= tp
->num
;
7400 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7403 CATCH (e
, RETURN_MASK_ERROR
)
7405 /* We want to ignore errors here. */
7410 /* A helper for check_exception_resume that sets an
7411 exception-breakpoint based on a SystemTap probe. */
7414 insert_exception_resume_from_probe (struct thread_info
*tp
,
7415 const struct bound_probe
*probe
,
7416 struct frame_info
*frame
)
7418 struct value
*arg_value
;
7420 struct breakpoint
*bp
;
7422 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7426 handler
= value_as_address (arg_value
);
7429 fprintf_unfiltered (gdb_stdlog
,
7430 "infrun: exception resume at %s\n",
7431 paddress (get_objfile_arch (probe
->objfile
),
7434 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7435 handler
, bp_exception_resume
);
7436 bp
->thread
= tp
->num
;
7437 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7440 /* This is called when an exception has been intercepted. Check to
7441 see whether the exception's destination is of interest, and if so,
7442 set an exception resume breakpoint there. */
7445 check_exception_resume (struct execution_control_state
*ecs
,
7446 struct frame_info
*frame
)
7448 struct bound_probe probe
;
7449 struct symbol
*func
;
7451 /* First see if this exception unwinding breakpoint was set via a
7452 SystemTap probe point. If so, the probe has two arguments: the
7453 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7454 set a breakpoint there. */
7455 probe
= find_probe_by_pc (get_frame_pc (frame
));
7458 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7462 func
= get_frame_function (frame
);
7468 const struct block
*b
;
7469 struct block_iterator iter
;
7473 /* The exception breakpoint is a thread-specific breakpoint on
7474 the unwinder's debug hook, declared as:
7476 void _Unwind_DebugHook (void *cfa, void *handler);
7478 The CFA argument indicates the frame to which control is
7479 about to be transferred. HANDLER is the destination PC.
7481 We ignore the CFA and set a temporary breakpoint at HANDLER.
7482 This is not extremely efficient but it avoids issues in gdb
7483 with computing the DWARF CFA, and it also works even in weird
7484 cases such as throwing an exception from inside a signal
7487 b
= SYMBOL_BLOCK_VALUE (func
);
7488 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7490 if (!SYMBOL_IS_ARGUMENT (sym
))
7497 insert_exception_resume_breakpoint (ecs
->event_thread
,
7503 CATCH (e
, RETURN_MASK_ERROR
)
7510 stop_waiting (struct execution_control_state
*ecs
)
7513 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7515 clear_step_over_info ();
7517 /* Let callers know we don't want to wait for the inferior anymore. */
7518 ecs
->wait_some_more
= 0;
7520 /* If all-stop, but the target is always in non-stop mode, stop all
7521 threads now that we're presenting the stop to the user. */
7522 if (!non_stop
&& target_is_non_stop_p ())
7523 stop_all_threads ();
7526 /* Like keep_going, but passes the signal to the inferior, even if the
7527 signal is set to nopass. */
7530 keep_going_pass_signal (struct execution_control_state
*ecs
)
7532 /* Make sure normal_stop is called if we get a QUIT handled before
7534 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
7536 gdb_assert (ptid_equal (ecs
->event_thread
->ptid
, inferior_ptid
));
7537 gdb_assert (!ecs
->event_thread
->resumed
);
7539 /* Save the pc before execution, to compare with pc after stop. */
7540 ecs
->event_thread
->prev_pc
7541 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
7543 if (ecs
->event_thread
->control
.trap_expected
)
7545 struct thread_info
*tp
= ecs
->event_thread
;
7548 fprintf_unfiltered (gdb_stdlog
,
7549 "infrun: %s has trap_expected set, "
7550 "resuming to collect trap\n",
7551 target_pid_to_str (tp
->ptid
));
7553 /* We haven't yet gotten our trap, and either: intercepted a
7554 non-signal event (e.g., a fork); or took a signal which we
7555 are supposed to pass through to the inferior. Simply
7557 discard_cleanups (old_cleanups
);
7558 resume (ecs
->event_thread
->suspend
.stop_signal
);
7560 else if (step_over_info_valid_p ())
7562 /* Another thread is stepping over a breakpoint in-line. If
7563 this thread needs a step-over too, queue the request. In
7564 either case, this resume must be deferred for later. */
7565 struct thread_info
*tp
= ecs
->event_thread
;
7567 if (ecs
->hit_singlestep_breakpoint
7568 || thread_still_needs_step_over (tp
))
7571 fprintf_unfiltered (gdb_stdlog
,
7572 "infrun: step-over already in progress: "
7573 "step-over for %s deferred\n",
7574 target_pid_to_str (tp
->ptid
));
7575 thread_step_over_chain_enqueue (tp
);
7580 fprintf_unfiltered (gdb_stdlog
,
7581 "infrun: step-over in progress: "
7582 "resume of %s deferred\n",
7583 target_pid_to_str (tp
->ptid
));
7586 discard_cleanups (old_cleanups
);
7590 struct regcache
*regcache
= get_current_regcache ();
7593 step_over_what step_what
;
7595 /* Either the trap was not expected, but we are continuing
7596 anyway (if we got a signal, the user asked it be passed to
7599 We got our expected trap, but decided we should resume from
7602 We're going to run this baby now!
7604 Note that insert_breakpoints won't try to re-insert
7605 already inserted breakpoints. Therefore, we don't
7606 care if breakpoints were already inserted, or not. */
7608 /* If we need to step over a breakpoint, and we're not using
7609 displaced stepping to do so, insert all breakpoints
7610 (watchpoints, etc.) but the one we're stepping over, step one
7611 instruction, and then re-insert the breakpoint when that step
7614 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7616 remove_bp
= (ecs
->hit_singlestep_breakpoint
7617 || (step_what
& STEP_OVER_BREAKPOINT
));
7618 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7620 /* We can't use displaced stepping if we need to step past a
7621 watchpoint. The instruction copied to the scratch pad would
7622 still trigger the watchpoint. */
7624 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7626 set_step_over_info (get_regcache_aspace (regcache
),
7627 regcache_read_pc (regcache
), remove_wps
);
7629 else if (remove_wps
)
7630 set_step_over_info (NULL
, 0, remove_wps
);
7632 /* If we now need to do an in-line step-over, we need to stop
7633 all other threads. Note this must be done before
7634 insert_breakpoints below, because that removes the breakpoint
7635 we're about to step over, otherwise other threads could miss
7637 if (step_over_info_valid_p () && target_is_non_stop_p ())
7638 stop_all_threads ();
7640 /* Stop stepping if inserting breakpoints fails. */
7643 insert_breakpoints ();
7645 CATCH (e
, RETURN_MASK_ERROR
)
7647 exception_print (gdb_stderr
, e
);
7649 discard_cleanups (old_cleanups
);
7654 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7656 discard_cleanups (old_cleanups
);
7657 resume (ecs
->event_thread
->suspend
.stop_signal
);
7660 prepare_to_wait (ecs
);
7663 /* Called when we should continue running the inferior, because the
7664 current event doesn't cause a user visible stop. This does the
7665 resuming part; waiting for the next event is done elsewhere. */
7668 keep_going (struct execution_control_state
*ecs
)
7670 if (ecs
->event_thread
->control
.trap_expected
7671 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7672 ecs
->event_thread
->control
.trap_expected
= 0;
7674 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7675 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7676 keep_going_pass_signal (ecs
);
7679 /* This function normally comes after a resume, before
7680 handle_inferior_event exits. It takes care of any last bits of
7681 housekeeping, and sets the all-important wait_some_more flag. */
7684 prepare_to_wait (struct execution_control_state
*ecs
)
7687 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7689 ecs
->wait_some_more
= 1;
7691 if (!target_is_async_p ())
7692 mark_infrun_async_event_handler ();
7695 /* We are done with the step range of a step/next/si/ni command.
7696 Called once for each n of a "step n" operation. */
7699 end_stepping_range (struct execution_control_state
*ecs
)
7701 ecs
->event_thread
->control
.stop_step
= 1;
7705 /* Several print_*_reason functions to print why the inferior has stopped.
7706 We always print something when the inferior exits, or receives a signal.
7707 The rest of the cases are dealt with later on in normal_stop and
7708 print_it_typical. Ideally there should be a call to one of these
7709 print_*_reason functions functions from handle_inferior_event each time
7710 stop_waiting is called.
7712 Note that we don't call these directly, instead we delegate that to
7713 the interpreters, through observers. Interpreters then call these
7714 with whatever uiout is right. */
7717 print_end_stepping_range_reason (struct ui_out
*uiout
)
7719 /* For CLI-like interpreters, print nothing. */
7721 if (ui_out_is_mi_like_p (uiout
))
7723 ui_out_field_string (uiout
, "reason",
7724 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7729 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7731 annotate_signalled ();
7732 if (ui_out_is_mi_like_p (uiout
))
7734 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7735 ui_out_text (uiout
, "\nProgram terminated with signal ");
7736 annotate_signal_name ();
7737 ui_out_field_string (uiout
, "signal-name",
7738 gdb_signal_to_name (siggnal
));
7739 annotate_signal_name_end ();
7740 ui_out_text (uiout
, ", ");
7741 annotate_signal_string ();
7742 ui_out_field_string (uiout
, "signal-meaning",
7743 gdb_signal_to_string (siggnal
));
7744 annotate_signal_string_end ();
7745 ui_out_text (uiout
, ".\n");
7746 ui_out_text (uiout
, "The program no longer exists.\n");
7750 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7752 struct inferior
*inf
= current_inferior ();
7753 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
7755 annotate_exited (exitstatus
);
7758 if (ui_out_is_mi_like_p (uiout
))
7759 ui_out_field_string (uiout
, "reason",
7760 async_reason_lookup (EXEC_ASYNC_EXITED
));
7761 ui_out_text (uiout
, "[Inferior ");
7762 ui_out_text (uiout
, plongest (inf
->num
));
7763 ui_out_text (uiout
, " (");
7764 ui_out_text (uiout
, pidstr
);
7765 ui_out_text (uiout
, ") exited with code ");
7766 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
7767 ui_out_text (uiout
, "]\n");
7771 if (ui_out_is_mi_like_p (uiout
))
7773 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7774 ui_out_text (uiout
, "[Inferior ");
7775 ui_out_text (uiout
, plongest (inf
->num
));
7776 ui_out_text (uiout
, " (");
7777 ui_out_text (uiout
, pidstr
);
7778 ui_out_text (uiout
, ") exited normally]\n");
7783 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7787 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
7789 struct thread_info
*t
= inferior_thread ();
7791 ui_out_text (uiout
, "\n[");
7792 ui_out_field_string (uiout
, "thread-name",
7793 target_pid_to_str (t
->ptid
));
7794 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
7795 ui_out_text (uiout
, " stopped");
7799 ui_out_text (uiout
, "\nProgram received signal ");
7800 annotate_signal_name ();
7801 if (ui_out_is_mi_like_p (uiout
))
7803 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
7804 ui_out_field_string (uiout
, "signal-name",
7805 gdb_signal_to_name (siggnal
));
7806 annotate_signal_name_end ();
7807 ui_out_text (uiout
, ", ");
7808 annotate_signal_string ();
7809 ui_out_field_string (uiout
, "signal-meaning",
7810 gdb_signal_to_string (siggnal
));
7811 annotate_signal_string_end ();
7813 ui_out_text (uiout
, ".\n");
7817 print_no_history_reason (struct ui_out
*uiout
)
7819 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
7822 /* Print current location without a level number, if we have changed
7823 functions or hit a breakpoint. Print source line if we have one.
7824 bpstat_print contains the logic deciding in detail what to print,
7825 based on the event(s) that just occurred. */
7828 print_stop_location (struct target_waitstatus
*ws
)
7831 enum print_what source_flag
;
7832 int do_frame_printing
= 1;
7833 struct thread_info
*tp
= inferior_thread ();
7835 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
7839 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
7840 should) carry around the function and does (or should) use
7841 that when doing a frame comparison. */
7842 if (tp
->control
.stop_step
7843 && frame_id_eq (tp
->control
.step_frame_id
,
7844 get_frame_id (get_current_frame ()))
7845 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
7847 /* Finished step, just print source line. */
7848 source_flag
= SRC_LINE
;
7852 /* Print location and source line. */
7853 source_flag
= SRC_AND_LOC
;
7856 case PRINT_SRC_AND_LOC
:
7857 /* Print location and source line. */
7858 source_flag
= SRC_AND_LOC
;
7860 case PRINT_SRC_ONLY
:
7861 source_flag
= SRC_LINE
;
7864 /* Something bogus. */
7865 source_flag
= SRC_LINE
;
7866 do_frame_printing
= 0;
7869 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
7872 /* The behavior of this routine with respect to the source
7874 SRC_LINE: Print only source line
7875 LOCATION: Print only location
7876 SRC_AND_LOC: Print location and source line. */
7877 if (do_frame_printing
)
7878 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
7881 /* Cleanup that restores a previous current uiout. */
7884 restore_current_uiout_cleanup (void *arg
)
7886 struct ui_out
*saved_uiout
= (struct ui_out
*) arg
;
7888 current_uiout
= saved_uiout
;
7894 print_stop_event (struct ui_out
*uiout
)
7896 struct cleanup
*old_chain
;
7897 struct target_waitstatus last
;
7899 struct thread_info
*tp
;
7901 get_last_target_status (&last_ptid
, &last
);
7903 old_chain
= make_cleanup (restore_current_uiout_cleanup
, current_uiout
);
7904 current_uiout
= uiout
;
7906 print_stop_location (&last
);
7908 /* Display the auto-display expressions. */
7911 do_cleanups (old_chain
);
7913 tp
= inferior_thread ();
7914 if (tp
->thread_fsm
!= NULL
7915 && thread_fsm_finished_p (tp
->thread_fsm
))
7917 struct return_value_info
*rv
;
7919 rv
= thread_fsm_return_value (tp
->thread_fsm
);
7921 print_return_value (uiout
, rv
);
7928 maybe_remove_breakpoints (void)
7930 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
7932 if (remove_breakpoints ())
7934 target_terminal_ours_for_output ();
7935 printf_filtered (_("Cannot remove breakpoints because "
7936 "program is no longer writable.\nFurther "
7937 "execution is probably impossible.\n"));
7942 /* The execution context that just caused a normal stop. */
7949 /* The event PTID. */
7953 /* If stopp for a thread event, this is the thread that caused the
7955 struct thread_info
*thread
;
7957 /* The inferior that caused the stop. */
7961 /* Returns a new stop context. If stopped for a thread event, this
7962 takes a strong reference to the thread. */
7964 static struct stop_context
*
7965 save_stop_context (void)
7967 struct stop_context
*sc
= XNEW (struct stop_context
);
7969 sc
->stop_id
= get_stop_id ();
7970 sc
->ptid
= inferior_ptid
;
7971 sc
->inf_num
= current_inferior ()->num
;
7973 if (!ptid_equal (inferior_ptid
, null_ptid
))
7975 /* Take a strong reference so that the thread can't be deleted
7977 sc
->thread
= inferior_thread ();
7978 sc
->thread
->refcount
++;
7986 /* Release a stop context previously created with save_stop_context.
7987 Releases the strong reference to the thread as well. */
7990 release_stop_context_cleanup (void *arg
)
7992 struct stop_context
*sc
= (struct stop_context
*) arg
;
7994 if (sc
->thread
!= NULL
)
7995 sc
->thread
->refcount
--;
7999 /* Return true if the current context no longer matches the saved stop
8003 stop_context_changed (struct stop_context
*prev
)
8005 if (!ptid_equal (prev
->ptid
, inferior_ptid
))
8007 if (prev
->inf_num
!= current_inferior ()->num
)
8009 if (prev
->thread
!= NULL
&& prev
->thread
->state
!= THREAD_STOPPED
)
8011 if (get_stop_id () != prev
->stop_id
)
8021 struct target_waitstatus last
;
8023 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
8026 get_last_target_status (&last_ptid
, &last
);
8030 /* If an exception is thrown from this point on, make sure to
8031 propagate GDB's knowledge of the executing state to the
8032 frontend/user running state. A QUIT is an easy exception to see
8033 here, so do this before any filtered output. */
8035 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
8036 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8037 || last
.kind
== TARGET_WAITKIND_EXITED
)
8039 /* On some targets, we may still have live threads in the
8040 inferior when we get a process exit event. E.g., for
8041 "checkpoint", when the current checkpoint/fork exits,
8042 linux-fork.c automatically switches to another fork from
8043 within target_mourn_inferior. */
8044 if (!ptid_equal (inferior_ptid
, null_ptid
))
8046 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
8047 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
8050 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8051 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
8053 /* As we're presenting a stop, and potentially removing breakpoints,
8054 update the thread list so we can tell whether there are threads
8055 running on the target. With target remote, for example, we can
8056 only learn about new threads when we explicitly update the thread
8057 list. Do this before notifying the interpreters about signal
8058 stops, end of stepping ranges, etc., so that the "new thread"
8059 output is emitted before e.g., "Program received signal FOO",
8060 instead of after. */
8061 update_thread_list ();
8063 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8064 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
8066 /* As with the notification of thread events, we want to delay
8067 notifying the user that we've switched thread context until
8068 the inferior actually stops.
8070 There's no point in saying anything if the inferior has exited.
8071 Note that SIGNALLED here means "exited with a signal", not
8072 "received a signal".
8074 Also skip saying anything in non-stop mode. In that mode, as we
8075 don't want GDB to switch threads behind the user's back, to avoid
8076 races where the user is typing a command to apply to thread x,
8077 but GDB switches to thread y before the user finishes entering
8078 the command, fetch_inferior_event installs a cleanup to restore
8079 the current thread back to the thread the user had selected right
8080 after this event is handled, so we're not really switching, only
8081 informing of a stop. */
8083 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
8084 && target_has_execution
8085 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8086 && last
.kind
!= TARGET_WAITKIND_EXITED
8087 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8089 target_terminal_ours_for_output ();
8090 printf_filtered (_("[Switching to %s]\n"),
8091 target_pid_to_str (inferior_ptid
));
8092 annotate_thread_changed ();
8093 previous_inferior_ptid
= inferior_ptid
;
8096 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8098 gdb_assert (sync_execution
|| !target_can_async_p ());
8100 target_terminal_ours_for_output ();
8101 printf_filtered (_("No unwaited-for children left.\n"));
8104 /* Note: this depends on the update_thread_list call above. */
8105 maybe_remove_breakpoints ();
8107 /* If an auto-display called a function and that got a signal,
8108 delete that auto-display to avoid an infinite recursion. */
8110 if (stopped_by_random_signal
)
8111 disable_current_display ();
8113 target_terminal_ours ();
8114 async_enable_stdin ();
8116 /* Let the user/frontend see the threads as stopped. */
8117 do_cleanups (old_chain
);
8119 /* Select innermost stack frame - i.e., current frame is frame 0,
8120 and current location is based on that. Handle the case where the
8121 dummy call is returning after being stopped. E.g. the dummy call
8122 previously hit a breakpoint. (If the dummy call returns
8123 normally, we won't reach here.) Do this before the stop hook is
8124 run, so that it doesn't get to see the temporary dummy frame,
8125 which is not where we'll present the stop. */
8126 if (has_stack_frames ())
8128 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8130 /* Pop the empty frame that contains the stack dummy. This
8131 also restores inferior state prior to the call (struct
8132 infcall_suspend_state). */
8133 struct frame_info
*frame
= get_current_frame ();
8135 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8137 /* frame_pop calls reinit_frame_cache as the last thing it
8138 does which means there's now no selected frame. */
8141 select_frame (get_current_frame ());
8143 /* Set the current source location. */
8144 set_current_sal_from_frame (get_current_frame ());
8147 /* Look up the hook_stop and run it (CLI internally handles problem
8148 of stop_command's pre-hook not existing). */
8149 if (stop_command
!= NULL
)
8151 struct stop_context
*saved_context
= save_stop_context ();
8152 struct cleanup
*old_chain
8153 = make_cleanup (release_stop_context_cleanup
, saved_context
);
8155 catch_errors (hook_stop_stub
, stop_command
,
8156 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
8158 /* If the stop hook resumes the target, then there's no point in
8159 trying to notify about the previous stop; its context is
8160 gone. Likewise if the command switches thread or inferior --
8161 the observers would print a stop for the wrong
8163 if (stop_context_changed (saved_context
))
8165 do_cleanups (old_chain
);
8168 do_cleanups (old_chain
);
8171 /* Notify observers about the stop. This is where the interpreters
8172 print the stop event. */
8173 if (!ptid_equal (inferior_ptid
, null_ptid
))
8174 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
8177 observer_notify_normal_stop (NULL
, stop_print_frame
);
8179 annotate_stopped ();
8181 if (target_has_execution
)
8183 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8184 && last
.kind
!= TARGET_WAITKIND_EXITED
)
8185 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8186 Delete any breakpoint that is to be deleted at the next stop. */
8187 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8190 /* Try to get rid of automatically added inferiors that are no
8191 longer needed. Keeping those around slows down things linearly.
8192 Note that this never removes the current inferior. */
8199 hook_stop_stub (void *cmd
)
8201 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
8206 signal_stop_state (int signo
)
8208 return signal_stop
[signo
];
8212 signal_print_state (int signo
)
8214 return signal_print
[signo
];
8218 signal_pass_state (int signo
)
8220 return signal_program
[signo
];
8224 signal_cache_update (int signo
)
8228 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8229 signal_cache_update (signo
);
8234 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8235 && signal_print
[signo
] == 0
8236 && signal_program
[signo
] == 1
8237 && signal_catch
[signo
] == 0);
8241 signal_stop_update (int signo
, int state
)
8243 int ret
= signal_stop
[signo
];
8245 signal_stop
[signo
] = state
;
8246 signal_cache_update (signo
);
8251 signal_print_update (int signo
, int state
)
8253 int ret
= signal_print
[signo
];
8255 signal_print
[signo
] = state
;
8256 signal_cache_update (signo
);
8261 signal_pass_update (int signo
, int state
)
8263 int ret
= signal_program
[signo
];
8265 signal_program
[signo
] = state
;
8266 signal_cache_update (signo
);
8270 /* Update the global 'signal_catch' from INFO and notify the
8274 signal_catch_update (const unsigned int *info
)
8278 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8279 signal_catch
[i
] = info
[i
] > 0;
8280 signal_cache_update (-1);
8281 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8285 sig_print_header (void)
8287 printf_filtered (_("Signal Stop\tPrint\tPass "
8288 "to program\tDescription\n"));
8292 sig_print_info (enum gdb_signal oursig
)
8294 const char *name
= gdb_signal_to_name (oursig
);
8295 int name_padding
= 13 - strlen (name
);
8297 if (name_padding
<= 0)
8300 printf_filtered ("%s", name
);
8301 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8302 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8303 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8304 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8305 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8308 /* Specify how various signals in the inferior should be handled. */
8311 handle_command (char *args
, int from_tty
)
8314 int digits
, wordlen
;
8315 int sigfirst
, signum
, siglast
;
8316 enum gdb_signal oursig
;
8319 unsigned char *sigs
;
8320 struct cleanup
*old_chain
;
8324 error_no_arg (_("signal to handle"));
8327 /* Allocate and zero an array of flags for which signals to handle. */
8329 nsigs
= (int) GDB_SIGNAL_LAST
;
8330 sigs
= (unsigned char *) alloca (nsigs
);
8331 memset (sigs
, 0, nsigs
);
8333 /* Break the command line up into args. */
8335 argv
= gdb_buildargv (args
);
8336 old_chain
= make_cleanup_freeargv (argv
);
8338 /* Walk through the args, looking for signal oursigs, signal names, and
8339 actions. Signal numbers and signal names may be interspersed with
8340 actions, with the actions being performed for all signals cumulatively
8341 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8343 while (*argv
!= NULL
)
8345 wordlen
= strlen (*argv
);
8346 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
8350 sigfirst
= siglast
= -1;
8352 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
8354 /* Apply action to all signals except those used by the
8355 debugger. Silently skip those. */
8358 siglast
= nsigs
- 1;
8360 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
8362 SET_SIGS (nsigs
, sigs
, signal_stop
);
8363 SET_SIGS (nsigs
, sigs
, signal_print
);
8365 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
8367 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8369 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
8371 SET_SIGS (nsigs
, sigs
, signal_print
);
8373 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
8375 SET_SIGS (nsigs
, sigs
, signal_program
);
8377 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
8379 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8381 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
8383 SET_SIGS (nsigs
, sigs
, signal_program
);
8385 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
8387 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8388 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8390 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
8392 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8394 else if (digits
> 0)
8396 /* It is numeric. The numeric signal refers to our own
8397 internal signal numbering from target.h, not to host/target
8398 signal number. This is a feature; users really should be
8399 using symbolic names anyway, and the common ones like
8400 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8402 sigfirst
= siglast
= (int)
8403 gdb_signal_from_command (atoi (*argv
));
8404 if ((*argv
)[digits
] == '-')
8407 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
8409 if (sigfirst
> siglast
)
8411 /* Bet he didn't figure we'd think of this case... */
8419 oursig
= gdb_signal_from_name (*argv
);
8420 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8422 sigfirst
= siglast
= (int) oursig
;
8426 /* Not a number and not a recognized flag word => complain. */
8427 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
8431 /* If any signal numbers or symbol names were found, set flags for
8432 which signals to apply actions to. */
8434 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8436 switch ((enum gdb_signal
) signum
)
8438 case GDB_SIGNAL_TRAP
:
8439 case GDB_SIGNAL_INT
:
8440 if (!allsigs
&& !sigs
[signum
])
8442 if (query (_("%s is used by the debugger.\n\
8443 Are you sure you want to change it? "),
8444 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8450 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8451 gdb_flush (gdb_stdout
);
8456 case GDB_SIGNAL_DEFAULT
:
8457 case GDB_SIGNAL_UNKNOWN
:
8458 /* Make sure that "all" doesn't print these. */
8469 for (signum
= 0; signum
< nsigs
; signum
++)
8472 signal_cache_update (-1);
8473 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8474 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8478 /* Show the results. */
8479 sig_print_header ();
8480 for (; signum
< nsigs
; signum
++)
8482 sig_print_info ((enum gdb_signal
) signum
);
8488 do_cleanups (old_chain
);
8491 /* Complete the "handle" command. */
8493 static VEC (char_ptr
) *
8494 handle_completer (struct cmd_list_element
*ignore
,
8495 const char *text
, const char *word
)
8497 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
8498 static const char * const keywords
[] =
8512 vec_signals
= signal_completer (ignore
, text
, word
);
8513 vec_keywords
= complete_on_enum (keywords
, word
, word
);
8515 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
8516 VEC_free (char_ptr
, vec_signals
);
8517 VEC_free (char_ptr
, vec_keywords
);
8522 gdb_signal_from_command (int num
)
8524 if (num
>= 1 && num
<= 15)
8525 return (enum gdb_signal
) num
;
8526 error (_("Only signals 1-15 are valid as numeric signals.\n\
8527 Use \"info signals\" for a list of symbolic signals."));
8530 /* Print current contents of the tables set by the handle command.
8531 It is possible we should just be printing signals actually used
8532 by the current target (but for things to work right when switching
8533 targets, all signals should be in the signal tables). */
8536 signals_info (char *signum_exp
, int from_tty
)
8538 enum gdb_signal oursig
;
8540 sig_print_header ();
8544 /* First see if this is a symbol name. */
8545 oursig
= gdb_signal_from_name (signum_exp
);
8546 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8548 /* No, try numeric. */
8550 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8552 sig_print_info (oursig
);
8556 printf_filtered ("\n");
8557 /* These ugly casts brought to you by the native VAX compiler. */
8558 for (oursig
= GDB_SIGNAL_FIRST
;
8559 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8560 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8564 if (oursig
!= GDB_SIGNAL_UNKNOWN
8565 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8566 sig_print_info (oursig
);
8569 printf_filtered (_("\nUse the \"handle\" command "
8570 "to change these tables.\n"));
8573 /* Check if it makes sense to read $_siginfo from the current thread
8574 at this point. If not, throw an error. */
8577 validate_siginfo_access (void)
8579 /* No current inferior, no siginfo. */
8580 if (ptid_equal (inferior_ptid
, null_ptid
))
8581 error (_("No thread selected."));
8583 /* Don't try to read from a dead thread. */
8584 if (is_exited (inferior_ptid
))
8585 error (_("The current thread has terminated"));
8587 /* ... or from a spinning thread. */
8588 if (is_running (inferior_ptid
))
8589 error (_("Selected thread is running."));
8592 /* The $_siginfo convenience variable is a bit special. We don't know
8593 for sure the type of the value until we actually have a chance to
8594 fetch the data. The type can change depending on gdbarch, so it is
8595 also dependent on which thread you have selected.
8597 1. making $_siginfo be an internalvar that creates a new value on
8600 2. making the value of $_siginfo be an lval_computed value. */
8602 /* This function implements the lval_computed support for reading a
8606 siginfo_value_read (struct value
*v
)
8608 LONGEST transferred
;
8610 validate_siginfo_access ();
8613 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8615 value_contents_all_raw (v
),
8617 TYPE_LENGTH (value_type (v
)));
8619 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8620 error (_("Unable to read siginfo"));
8623 /* This function implements the lval_computed support for writing a
8627 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8629 LONGEST transferred
;
8631 validate_siginfo_access ();
8633 transferred
= target_write (¤t_target
,
8634 TARGET_OBJECT_SIGNAL_INFO
,
8636 value_contents_all_raw (fromval
),
8638 TYPE_LENGTH (value_type (fromval
)));
8640 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8641 error (_("Unable to write siginfo"));
8644 static const struct lval_funcs siginfo_value_funcs
=
8650 /* Return a new value with the correct type for the siginfo object of
8651 the current thread using architecture GDBARCH. Return a void value
8652 if there's no object available. */
8654 static struct value
*
8655 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8658 if (target_has_stack
8659 && !ptid_equal (inferior_ptid
, null_ptid
)
8660 && gdbarch_get_siginfo_type_p (gdbarch
))
8662 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8664 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8667 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8671 /* infcall_suspend_state contains state about the program itself like its
8672 registers and any signal it received when it last stopped.
8673 This state must be restored regardless of how the inferior function call
8674 ends (either successfully, or after it hits a breakpoint or signal)
8675 if the program is to properly continue where it left off. */
8677 struct infcall_suspend_state
8679 struct thread_suspend_state thread_suspend
;
8683 struct regcache
*registers
;
8685 /* Format of SIGINFO_DATA or NULL if it is not present. */
8686 struct gdbarch
*siginfo_gdbarch
;
8688 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8689 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8690 content would be invalid. */
8691 gdb_byte
*siginfo_data
;
8694 struct infcall_suspend_state
*
8695 save_infcall_suspend_state (void)
8697 struct infcall_suspend_state
*inf_state
;
8698 struct thread_info
*tp
= inferior_thread ();
8699 struct regcache
*regcache
= get_current_regcache ();
8700 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8701 gdb_byte
*siginfo_data
= NULL
;
8703 if (gdbarch_get_siginfo_type_p (gdbarch
))
8705 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8706 size_t len
= TYPE_LENGTH (type
);
8707 struct cleanup
*back_to
;
8709 siginfo_data
= (gdb_byte
*) xmalloc (len
);
8710 back_to
= make_cleanup (xfree
, siginfo_data
);
8712 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8713 siginfo_data
, 0, len
) == len
)
8714 discard_cleanups (back_to
);
8717 /* Errors ignored. */
8718 do_cleanups (back_to
);
8719 siginfo_data
= NULL
;
8723 inf_state
= XCNEW (struct infcall_suspend_state
);
8727 inf_state
->siginfo_gdbarch
= gdbarch
;
8728 inf_state
->siginfo_data
= siginfo_data
;
8731 inf_state
->thread_suspend
= tp
->suspend
;
8733 /* run_inferior_call will not use the signal due to its `proceed' call with
8734 GDB_SIGNAL_0 anyway. */
8735 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8737 inf_state
->stop_pc
= stop_pc
;
8739 inf_state
->registers
= regcache_dup (regcache
);
8744 /* Restore inferior session state to INF_STATE. */
8747 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8749 struct thread_info
*tp
= inferior_thread ();
8750 struct regcache
*regcache
= get_current_regcache ();
8751 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8753 tp
->suspend
= inf_state
->thread_suspend
;
8755 stop_pc
= inf_state
->stop_pc
;
8757 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8759 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8761 /* Errors ignored. */
8762 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8763 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8766 /* The inferior can be gone if the user types "print exit(0)"
8767 (and perhaps other times). */
8768 if (target_has_execution
)
8769 /* NB: The register write goes through to the target. */
8770 regcache_cpy (regcache
, inf_state
->registers
);
8772 discard_infcall_suspend_state (inf_state
);
8776 do_restore_infcall_suspend_state_cleanup (void *state
)
8778 restore_infcall_suspend_state ((struct infcall_suspend_state
*) state
);
8782 make_cleanup_restore_infcall_suspend_state
8783 (struct infcall_suspend_state
*inf_state
)
8785 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
8789 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8791 regcache_xfree (inf_state
->registers
);
8792 xfree (inf_state
->siginfo_data
);
8797 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8799 return inf_state
->registers
;
8802 /* infcall_control_state contains state regarding gdb's control of the
8803 inferior itself like stepping control. It also contains session state like
8804 the user's currently selected frame. */
8806 struct infcall_control_state
8808 struct thread_control_state thread_control
;
8809 struct inferior_control_state inferior_control
;
8812 enum stop_stack_kind stop_stack_dummy
;
8813 int stopped_by_random_signal
;
8815 /* ID if the selected frame when the inferior function call was made. */
8816 struct frame_id selected_frame_id
;
8819 /* Save all of the information associated with the inferior<==>gdb
8822 struct infcall_control_state
*
8823 save_infcall_control_state (void)
8825 struct infcall_control_state
*inf_status
=
8826 XNEW (struct infcall_control_state
);
8827 struct thread_info
*tp
= inferior_thread ();
8828 struct inferior
*inf
= current_inferior ();
8830 inf_status
->thread_control
= tp
->control
;
8831 inf_status
->inferior_control
= inf
->control
;
8833 tp
->control
.step_resume_breakpoint
= NULL
;
8834 tp
->control
.exception_resume_breakpoint
= NULL
;
8836 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
8837 chain. If caller's caller is walking the chain, they'll be happier if we
8838 hand them back the original chain when restore_infcall_control_state is
8840 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
8843 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
8844 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
8846 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
8852 restore_selected_frame (void *args
)
8854 struct frame_id
*fid
= (struct frame_id
*) args
;
8855 struct frame_info
*frame
;
8857 frame
= frame_find_by_id (*fid
);
8859 /* If inf_status->selected_frame_id is NULL, there was no previously
8863 warning (_("Unable to restore previously selected frame."));
8867 select_frame (frame
);
8872 /* Restore inferior session state to INF_STATUS. */
8875 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
8877 struct thread_info
*tp
= inferior_thread ();
8878 struct inferior
*inf
= current_inferior ();
8880 if (tp
->control
.step_resume_breakpoint
)
8881 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
8883 if (tp
->control
.exception_resume_breakpoint
)
8884 tp
->control
.exception_resume_breakpoint
->disposition
8885 = disp_del_at_next_stop
;
8887 /* Handle the bpstat_copy of the chain. */
8888 bpstat_clear (&tp
->control
.stop_bpstat
);
8890 tp
->control
= inf_status
->thread_control
;
8891 inf
->control
= inf_status
->inferior_control
;
8894 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
8895 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
8897 if (target_has_stack
)
8899 /* The point of catch_errors is that if the stack is clobbered,
8900 walking the stack might encounter a garbage pointer and
8901 error() trying to dereference it. */
8903 (restore_selected_frame
, &inf_status
->selected_frame_id
,
8904 "Unable to restore previously selected frame:\n",
8905 RETURN_MASK_ERROR
) == 0)
8906 /* Error in restoring the selected frame. Select the innermost
8908 select_frame (get_current_frame ());
8915 do_restore_infcall_control_state_cleanup (void *sts
)
8917 restore_infcall_control_state ((struct infcall_control_state
*) sts
);
8921 make_cleanup_restore_infcall_control_state
8922 (struct infcall_control_state
*inf_status
)
8924 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
8928 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
8930 if (inf_status
->thread_control
.step_resume_breakpoint
)
8931 inf_status
->thread_control
.step_resume_breakpoint
->disposition
8932 = disp_del_at_next_stop
;
8934 if (inf_status
->thread_control
.exception_resume_breakpoint
)
8935 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
8936 = disp_del_at_next_stop
;
8938 /* See save_infcall_control_state for info on stop_bpstat. */
8939 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
8944 /* restore_inferior_ptid() will be used by the cleanup machinery
8945 to restore the inferior_ptid value saved in a call to
8946 save_inferior_ptid(). */
8949 restore_inferior_ptid (void *arg
)
8951 ptid_t
*saved_ptid_ptr
= (ptid_t
*) arg
;
8953 inferior_ptid
= *saved_ptid_ptr
;
8957 /* Save the value of inferior_ptid so that it may be restored by a
8958 later call to do_cleanups(). Returns the struct cleanup pointer
8959 needed for later doing the cleanup. */
8962 save_inferior_ptid (void)
8964 ptid_t
*saved_ptid_ptr
= XNEW (ptid_t
);
8966 *saved_ptid_ptr
= inferior_ptid
;
8967 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
8973 clear_exit_convenience_vars (void)
8975 clear_internalvar (lookup_internalvar ("_exitsignal"));
8976 clear_internalvar (lookup_internalvar ("_exitcode"));
8980 /* User interface for reverse debugging:
8981 Set exec-direction / show exec-direction commands
8982 (returns error unless target implements to_set_exec_direction method). */
8984 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
8985 static const char exec_forward
[] = "forward";
8986 static const char exec_reverse
[] = "reverse";
8987 static const char *exec_direction
= exec_forward
;
8988 static const char *const exec_direction_names
[] = {
8995 set_exec_direction_func (char *args
, int from_tty
,
8996 struct cmd_list_element
*cmd
)
8998 if (target_can_execute_reverse
)
9000 if (!strcmp (exec_direction
, exec_forward
))
9001 execution_direction
= EXEC_FORWARD
;
9002 else if (!strcmp (exec_direction
, exec_reverse
))
9003 execution_direction
= EXEC_REVERSE
;
9007 exec_direction
= exec_forward
;
9008 error (_("Target does not support this operation."));
9013 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9014 struct cmd_list_element
*cmd
, const char *value
)
9016 switch (execution_direction
) {
9018 fprintf_filtered (out
, _("Forward.\n"));
9021 fprintf_filtered (out
, _("Reverse.\n"));
9024 internal_error (__FILE__
, __LINE__
,
9025 _("bogus execution_direction value: %d"),
9026 (int) execution_direction
);
9031 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9032 struct cmd_list_element
*c
, const char *value
)
9034 fprintf_filtered (file
, _("Resuming the execution of threads "
9035 "of all processes is %s.\n"), value
);
9038 /* Implementation of `siginfo' variable. */
9040 static const struct internalvar_funcs siginfo_funcs
=
9047 /* Callback for infrun's target events source. This is marked when a
9048 thread has a pending status to process. */
9051 infrun_async_inferior_event_handler (gdb_client_data data
)
9053 inferior_event_handler (INF_REG_EVENT
, NULL
);
9057 _initialize_infrun (void)
9061 struct cmd_list_element
*c
;
9063 /* Register extra event sources in the event loop. */
9064 infrun_async_inferior_event_token
9065 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
9067 add_info ("signals", signals_info
, _("\
9068 What debugger does when program gets various signals.\n\
9069 Specify a signal as argument to print info on that signal only."));
9070 add_info_alias ("handle", "signals", 0);
9072 c
= add_com ("handle", class_run
, handle_command
, _("\
9073 Specify how to handle signals.\n\
9074 Usage: handle SIGNAL [ACTIONS]\n\
9075 Args are signals and actions to apply to those signals.\n\
9076 If no actions are specified, the current settings for the specified signals\n\
9077 will be displayed instead.\n\
9079 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9080 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9081 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9082 The special arg \"all\" is recognized to mean all signals except those\n\
9083 used by the debugger, typically SIGTRAP and SIGINT.\n\
9085 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9086 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9087 Stop means reenter debugger if this signal happens (implies print).\n\
9088 Print means print a message if this signal happens.\n\
9089 Pass means let program see this signal; otherwise program doesn't know.\n\
9090 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9091 Pass and Stop may be combined.\n\
9093 Multiple signals may be specified. Signal numbers and signal names\n\
9094 may be interspersed with actions, with the actions being performed for\n\
9095 all signals cumulatively specified."));
9096 set_cmd_completer (c
, handle_completer
);
9099 stop_command
= add_cmd ("stop", class_obscure
,
9100 not_just_help_class_command
, _("\
9101 There is no `stop' command, but you can set a hook on `stop'.\n\
9102 This allows you to set a list of commands to be run each time execution\n\
9103 of the program stops."), &cmdlist
);
9105 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
9106 Set inferior debugging."), _("\
9107 Show inferior debugging."), _("\
9108 When non-zero, inferior specific debugging is enabled."),
9111 &setdebuglist
, &showdebuglist
);
9113 add_setshow_boolean_cmd ("displaced", class_maintenance
,
9114 &debug_displaced
, _("\
9115 Set displaced stepping debugging."), _("\
9116 Show displaced stepping debugging."), _("\
9117 When non-zero, displaced stepping specific debugging is enabled."),
9119 show_debug_displaced
,
9120 &setdebuglist
, &showdebuglist
);
9122 add_setshow_boolean_cmd ("non-stop", no_class
,
9124 Set whether gdb controls the inferior in non-stop mode."), _("\
9125 Show whether gdb controls the inferior in non-stop mode."), _("\
9126 When debugging a multi-threaded program and this setting is\n\
9127 off (the default, also called all-stop mode), when one thread stops\n\
9128 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9129 all other threads in the program while you interact with the thread of\n\
9130 interest. When you continue or step a thread, you can allow the other\n\
9131 threads to run, or have them remain stopped, but while you inspect any\n\
9132 thread's state, all threads stop.\n\
9134 In non-stop mode, when one thread stops, other threads can continue\n\
9135 to run freely. You'll be able to step each thread independently,\n\
9136 leave it stopped or free to run as needed."),
9142 numsigs
= (int) GDB_SIGNAL_LAST
;
9143 signal_stop
= XNEWVEC (unsigned char, numsigs
);
9144 signal_print
= XNEWVEC (unsigned char, numsigs
);
9145 signal_program
= XNEWVEC (unsigned char, numsigs
);
9146 signal_catch
= XNEWVEC (unsigned char, numsigs
);
9147 signal_pass
= XNEWVEC (unsigned char, numsigs
);
9148 for (i
= 0; i
< numsigs
; i
++)
9151 signal_print
[i
] = 1;
9152 signal_program
[i
] = 1;
9153 signal_catch
[i
] = 0;
9156 /* Signals caused by debugger's own actions should not be given to
9157 the program afterwards.
9159 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9160 explicitly specifies that it should be delivered to the target
9161 program. Typically, that would occur when a user is debugging a
9162 target monitor on a simulator: the target monitor sets a
9163 breakpoint; the simulator encounters this breakpoint and halts
9164 the simulation handing control to GDB; GDB, noting that the stop
9165 address doesn't map to any known breakpoint, returns control back
9166 to the simulator; the simulator then delivers the hardware
9167 equivalent of a GDB_SIGNAL_TRAP to the program being
9169 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9170 signal_program
[GDB_SIGNAL_INT
] = 0;
9172 /* Signals that are not errors should not normally enter the debugger. */
9173 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9174 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9175 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9176 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9177 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9178 signal_print
[GDB_SIGNAL_PROF
] = 0;
9179 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9180 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9181 signal_stop
[GDB_SIGNAL_IO
] = 0;
9182 signal_print
[GDB_SIGNAL_IO
] = 0;
9183 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9184 signal_print
[GDB_SIGNAL_POLL
] = 0;
9185 signal_stop
[GDB_SIGNAL_URG
] = 0;
9186 signal_print
[GDB_SIGNAL_URG
] = 0;
9187 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9188 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9189 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9190 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9192 /* These signals are used internally by user-level thread
9193 implementations. (See signal(5) on Solaris.) Like the above
9194 signals, a healthy program receives and handles them as part of
9195 its normal operation. */
9196 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9197 signal_print
[GDB_SIGNAL_LWP
] = 0;
9198 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9199 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9200 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9201 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9203 /* Update cached state. */
9204 signal_cache_update (-1);
9206 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9207 &stop_on_solib_events
, _("\
9208 Set stopping for shared library events."), _("\
9209 Show stopping for shared library events."), _("\
9210 If nonzero, gdb will give control to the user when the dynamic linker\n\
9211 notifies gdb of shared library events. The most common event of interest\n\
9212 to the user would be loading/unloading of a new library."),
9213 set_stop_on_solib_events
,
9214 show_stop_on_solib_events
,
9215 &setlist
, &showlist
);
9217 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9218 follow_fork_mode_kind_names
,
9219 &follow_fork_mode_string
, _("\
9220 Set debugger response to a program call of fork or vfork."), _("\
9221 Show debugger response to a program call of fork or vfork."), _("\
9222 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9223 parent - the original process is debugged after a fork\n\
9224 child - the new process is debugged after a fork\n\
9225 The unfollowed process will continue to run.\n\
9226 By default, the debugger will follow the parent process."),
9228 show_follow_fork_mode_string
,
9229 &setlist
, &showlist
);
9231 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9232 follow_exec_mode_names
,
9233 &follow_exec_mode_string
, _("\
9234 Set debugger response to a program call of exec."), _("\
9235 Show debugger response to a program call of exec."), _("\
9236 An exec call replaces the program image of a process.\n\
9238 follow-exec-mode can be:\n\
9240 new - the debugger creates a new inferior and rebinds the process\n\
9241 to this new inferior. The program the process was running before\n\
9242 the exec call can be restarted afterwards by restarting the original\n\
9245 same - the debugger keeps the process bound to the same inferior.\n\
9246 The new executable image replaces the previous executable loaded in\n\
9247 the inferior. Restarting the inferior after the exec call restarts\n\
9248 the executable the process was running after the exec call.\n\
9250 By default, the debugger will use the same inferior."),
9252 show_follow_exec_mode_string
,
9253 &setlist
, &showlist
);
9255 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9256 scheduler_enums
, &scheduler_mode
, _("\
9257 Set mode for locking scheduler during execution."), _("\
9258 Show mode for locking scheduler during execution."), _("\
9259 off == no locking (threads may preempt at any time)\n\
9260 on == full locking (no thread except the current thread may run)\n\
9261 This applies to both normal execution and replay mode.\n\
9262 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9263 In this mode, other threads may run during other commands.\n\
9264 This applies to both normal execution and replay mode.\n\
9265 replay == scheduler locked in replay mode and unlocked during normal execution."),
9266 set_schedlock_func
, /* traps on target vector */
9267 show_scheduler_mode
,
9268 &setlist
, &showlist
);
9270 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9271 Set mode for resuming threads of all processes."), _("\
9272 Show mode for resuming threads of all processes."), _("\
9273 When on, execution commands (such as 'continue' or 'next') resume all\n\
9274 threads of all processes. When off (which is the default), execution\n\
9275 commands only resume the threads of the current process. The set of\n\
9276 threads that are resumed is further refined by the scheduler-locking\n\
9277 mode (see help set scheduler-locking)."),
9279 show_schedule_multiple
,
9280 &setlist
, &showlist
);
9282 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9283 Set mode of the step operation."), _("\
9284 Show mode of the step operation."), _("\
9285 When set, doing a step over a function without debug line information\n\
9286 will stop at the first instruction of that function. Otherwise, the\n\
9287 function is skipped and the step command stops at a different source line."),
9289 show_step_stop_if_no_debug
,
9290 &setlist
, &showlist
);
9292 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9293 &can_use_displaced_stepping
, _("\
9294 Set debugger's willingness to use displaced stepping."), _("\
9295 Show debugger's willingness to use displaced stepping."), _("\
9296 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9297 supported by the target architecture. If off, gdb will not use displaced\n\
9298 stepping to step over breakpoints, even if such is supported by the target\n\
9299 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9300 if the target architecture supports it and non-stop mode is active, but will not\n\
9301 use it in all-stop mode (see help set non-stop)."),
9303 show_can_use_displaced_stepping
,
9304 &setlist
, &showlist
);
9306 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9307 &exec_direction
, _("Set direction of execution.\n\
9308 Options are 'forward' or 'reverse'."),
9309 _("Show direction of execution (forward/reverse)."),
9310 _("Tells gdb whether to execute forward or backward."),
9311 set_exec_direction_func
, show_exec_direction_func
,
9312 &setlist
, &showlist
);
9314 /* Set/show detach-on-fork: user-settable mode. */
9316 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9317 Set whether gdb will detach the child of a fork."), _("\
9318 Show whether gdb will detach the child of a fork."), _("\
9319 Tells gdb whether to detach the child of a fork."),
9320 NULL
, NULL
, &setlist
, &showlist
);
9322 /* Set/show disable address space randomization mode. */
9324 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9325 &disable_randomization
, _("\
9326 Set disabling of debuggee's virtual address space randomization."), _("\
9327 Show disabling of debuggee's virtual address space randomization."), _("\
9328 When this mode is on (which is the default), randomization of the virtual\n\
9329 address space is disabled. Standalone programs run with the randomization\n\
9330 enabled by default on some platforms."),
9331 &set_disable_randomization
,
9332 &show_disable_randomization
,
9333 &setlist
, &showlist
);
9335 /* ptid initializations */
9336 inferior_ptid
= null_ptid
;
9337 target_last_wait_ptid
= minus_one_ptid
;
9339 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
9340 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
9341 observer_attach_thread_exit (infrun_thread_thread_exit
);
9342 observer_attach_inferior_exit (infrun_inferior_exit
);
9344 /* Explicitly create without lookup, since that tries to create a
9345 value with a void typed value, and when we get here, gdbarch
9346 isn't initialized yet. At this point, we're quite sure there
9347 isn't another convenience variable of the same name. */
9348 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9350 add_setshow_boolean_cmd ("observer", no_class
,
9351 &observer_mode_1
, _("\
9352 Set whether gdb controls the inferior in observer mode."), _("\
9353 Show whether gdb controls the inferior in observer mode."), _("\
9354 In observer mode, GDB can get data from the inferior, but not\n\
9355 affect its execution. Registers and memory may not be changed,\n\
9356 breakpoints may not be set, and the program cannot be interrupted\n\