1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2017 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 #include "event-loop.h"
65 #include "thread-fsm.h"
66 #include "common/enum-flags.h"
67 #include "progspace-and-thread.h"
68 #include "common/gdb_optional.h"
69 #include "arch-utils.h"
71 /* Prototypes for local functions */
73 static void info_signals_command (char *, int);
75 static void handle_command (char *, int);
77 static void sig_print_info (enum gdb_signal);
79 static void sig_print_header (void);
81 static void resume_cleanups (void *);
83 static int follow_fork (void);
85 static int follow_fork_inferior (int follow_child, int detach_fork);
87 static void follow_inferior_reset_breakpoints (void);
89 static void set_schedlock_func (char *args, int from_tty,
90 struct cmd_list_element *c);
92 static int currently_stepping (struct thread_info *tp);
94 void nullify_last_target_wait_ptid (void);
96 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info *);
98 static void insert_step_resume_breakpoint_at_caller (struct frame_info *);
100 static void insert_longjmp_resume_breakpoint (struct gdbarch *, CORE_ADDR);
102 static int maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc);
104 /* Asynchronous signal handler registered as event loop source for
105 when we have pending events ready to be passed to the core. */
106 static struct async_event_handler *infrun_async_inferior_event_token;
108 /* Stores whether infrun_async was previously enabled or disabled.
109 Starts off as -1, indicating "never enabled/disabled". */
110 static int infrun_is_async = -1;
115 infrun_async (int enable)
117 if (infrun_is_async != enable)
119 infrun_is_async = enable;
122 fprintf_unfiltered (gdb_stdlog,
123 "infrun: infrun_async(%d)\n",
127 mark_async_event_handler (infrun_async_inferior_event_token);
129 clear_async_event_handler (infrun_async_inferior_event_token);
136 mark_infrun_async_event_handler (void)
138 mark_async_event_handler (infrun_async_inferior_event_token);
141 /* When set, stop the 'step' command if we enter a function which has
142 no line number information. The normal behavior is that we step
143 over such function. */
144 int step_stop_if_no_debug = 0;
146 show_step_stop_if_no_debug (struct ui_file *file, int from_tty,
147 struct cmd_list_element *c, const char *value)
149 fprintf_filtered (file, _("Mode of the step operation is %s.\n"), value);
152 /* proceed and normal_stop use this to notify the user when the
153 inferior stopped in a different thread than it had been running
156 static ptid_t previous_inferior_ptid;
158 /* If set (default for legacy reasons), when following a fork, GDB
159 will detach from one of the fork branches, child or parent.
160 Exactly which branch is detached depends on 'set follow-fork-mode'
163 static int detach_fork = 1;
165 int debug_displaced = 0;
167 show_debug_displaced (struct ui_file *file, int from_tty,
168 struct cmd_list_element *c, const char *value)
170 fprintf_filtered (file, _("Displace stepping debugging is %s.\n"), value);
173 unsigned int debug_infrun = 0;
175 show_debug_infrun (struct ui_file *file, int from_tty,
176 struct cmd_list_element *c, const char *value)
178 fprintf_filtered (file, _("Inferior debugging is %s.\n"), value);
182 /* Support for disabling address space randomization. */
184 int disable_randomization = 1;
187 show_disable_randomization (struct ui_file *file, int from_tty,
188 struct cmd_list_element *c, const char *value)
190 if (target_supports_disable_randomization ())
191 fprintf_filtered (file,
192 _("Disabling randomization of debuggee's "
193 "virtual address space is %s.\n"),
196 fputs_filtered (_("Disabling randomization of debuggee's "
197 "virtual address space is unsupported on\n"
198 "this platform.\n"), file);
202 set_disable_randomization (char *args, int from_tty,
203 struct cmd_list_element *c)
205 if (!target_supports_disable_randomization ())
206 error (_("Disabling randomization of debuggee's "
207 "virtual address space is unsupported on\n"
211 /* User interface for non-stop mode. */
214 static int non_stop_1 = 0;
217 set_non_stop (char *args, int from_tty,
218 struct cmd_list_element *c)
220 if (target_has_execution)
222 non_stop_1 = non_stop;
223 error (_("Cannot change this setting while the inferior is running."));
226 non_stop = non_stop_1;
230 show_non_stop (struct ui_file *file, int from_tty,
231 struct cmd_list_element *c, const char *value)
233 fprintf_filtered (file,
234 _("Controlling the inferior in non-stop mode is %s.\n"),
238 /* "Observer mode" is somewhat like a more extreme version of
239 non-stop, in which all GDB operations that might affect the
240 target's execution have been disabled. */
242 int observer_mode = 0;
243 static int observer_mode_1 = 0;
246 set_observer_mode (char *args, int from_tty,
247 struct cmd_list_element *c)
249 if (target_has_execution)
251 observer_mode_1 = observer_mode;
252 error (_("Cannot change this setting while the inferior is running."));
255 observer_mode = observer_mode_1;
257 may_write_registers = !observer_mode;
258 may_write_memory = !observer_mode;
259 may_insert_breakpoints = !observer_mode;
260 may_insert_tracepoints = !observer_mode;
261 /* We can insert fast tracepoints in or out of observer mode,
262 but enable them if we're going into this mode. */
264 may_insert_fast_tracepoints = 1;
265 may_stop = !observer_mode;
266 update_target_permissions ();
268 /* Going *into* observer mode we must force non-stop, then
269 going out we leave it that way. */
272 pagination_enabled = 0;
273 non_stop = non_stop_1 = 1;
277 printf_filtered (_("Observer mode is now %s.\n"),
278 (observer_mode ? "on" : "off"));
282 show_observer_mode (struct ui_file *file, int from_tty,
283 struct cmd_list_element *c, const char *value)
285 fprintf_filtered (file, _("Observer mode is %s.\n"), value);
288 /* This updates the value of observer mode based on changes in
289 permissions. Note that we are deliberately ignoring the values of
290 may-write-registers and may-write-memory, since the user may have
291 reason to enable these during a session, for instance to turn on a
292 debugging-related global. */
295 update_observer_mode (void)
299 newval = (!may_insert_breakpoints
300 && !may_insert_tracepoints
301 && may_insert_fast_tracepoints
305 /* Let the user know if things change. */
306 if (newval != observer_mode)
307 printf_filtered (_("Observer mode is now %s.\n"),
308 (newval ? "on" : "off"));
310 observer_mode = observer_mode_1 = newval;
313 /* Tables of how to react to signals; the user sets them. */
315 static unsigned char *signal_stop;
316 static unsigned char *signal_print;
317 static unsigned char *signal_program;
319 /* Table of signals that are registered with "catch signal". A
320 non-zero entry indicates that the signal is caught by some "catch
321 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
323 static unsigned char *signal_catch;
325 /* Table of signals that the target may silently handle.
326 This is automatically determined from the flags above,
327 and simply cached here. */
328 static unsigned char *signal_pass;
330 #define SET_SIGS(nsigs,sigs,flags) \
332 int signum = (nsigs); \
333 while (signum-- > 0) \
334 if ((sigs)[signum]) \
335 (flags)[signum] = 1; \
338 #define UNSET_SIGS(nsigs,sigs,flags) \
340 int signum = (nsigs); \
341 while (signum-- > 0) \
342 if ((sigs)[signum]) \
343 (flags)[signum] = 0; \
346 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
347 this function is to avoid exporting `signal_program'. */
350 update_signals_program_target (void)
352 target_program_signals ((int) GDB_SIGNAL_LAST, signal_program);
355 /* Value to pass to target_resume() to cause all threads to resume. */
357 #define RESUME_ALL minus_one_ptid
359 /* Command list pointer for the "stop" placeholder. */
361 static struct cmd_list_element *stop_command;
363 /* Nonzero if we want to give control to the user when we're notified
364 of shared library events by the dynamic linker. */
365 int stop_on_solib_events;
367 /* Enable or disable optional shared library event breakpoints
368 as appropriate when the above flag is changed. */
371 set_stop_on_solib_events (char *args, int from_tty, struct cmd_list_element *c)
373 update_solib_breakpoints ();
377 show_stop_on_solib_events (struct ui_file *file, int from_tty,
378 struct cmd_list_element *c, const char *value)
380 fprintf_filtered (file, _("Stopping for shared library events is %s.\n"),
384 /* Nonzero after stop if current stack frame should be printed. */
386 static int stop_print_frame;
388 /* This is a cached copy of the pid/waitstatus of the last event
389 returned by target_wait()/deprecated_target_wait_hook(). This
390 information is returned by get_last_target_status(). */
391 static ptid_t target_last_wait_ptid;
392 static struct target_waitstatus target_last_waitstatus;
394 static void context_switch (ptid_t ptid);
396 void init_thread_stepping_state (struct thread_info *tss);
398 static const char follow_fork_mode_child[] = "child";
399 static const char follow_fork_mode_parent[] = "parent";
401 static const char *const follow_fork_mode_kind_names[] = {
402 follow_fork_mode_child,
403 follow_fork_mode_parent,
407 static const char *follow_fork_mode_string = follow_fork_mode_parent;
409 show_follow_fork_mode_string (struct ui_file *file, int from_tty,
410 struct cmd_list_element *c, const char *value)
412 fprintf_filtered (file,
413 _("Debugger response to a program "
414 "call of fork or vfork is \"%s\".\n"),
419 /* Handle changes to the inferior list based on the type of fork,
420 which process is being followed, and whether the other process
421 should be detached. On entry inferior_ptid must be the ptid of
422 the fork parent. At return inferior_ptid is the ptid of the
423 followed inferior. */
426 follow_fork_inferior (int follow_child, int detach_fork)
429 ptid_t parent_ptid, child_ptid;
431 has_vforked = (inferior_thread ()->pending_follow.kind
432 == TARGET_WAITKIND_VFORKED);
433 parent_ptid = inferior_ptid;
434 child_ptid = inferior_thread ()->pending_follow.value.related_pid;
437 && !non_stop /* Non-stop always resumes both branches. */
438 && current_ui->prompt_state == PROMPT_BLOCKED
439 && !(follow_child || detach_fork || sched_multi))
441 /* The parent stays blocked inside the vfork syscall until the
442 child execs or exits. If we don't let the child run, then
443 the parent stays blocked. If we're telling the parent to run
444 in the foreground, the user will not be able to ctrl-c to get
445 back the terminal, effectively hanging the debug session. */
446 fprintf_filtered (gdb_stderr, _("\
447 Can not resume the parent process over vfork in the foreground while\n\
448 holding the child stopped. Try \"set detach-on-fork\" or \
449 \"set schedule-multiple\".\n"));
450 /* FIXME output string > 80 columns. */
456 /* Detach new forked process? */
459 /* Before detaching from the child, remove all breakpoints
460 from it. If we forked, then this has already been taken
461 care of by infrun.c. If we vforked however, any
462 breakpoint inserted in the parent is visible in the
463 child, even those added while stopped in a vfork
464 catchpoint. This will remove the breakpoints from the
465 parent also, but they'll be reinserted below. */
468 /* Keep breakpoints list in sync. */
469 remove_breakpoints_pid (ptid_get_pid (inferior_ptid));
472 if (info_verbose || debug_infrun)
474 /* Ensure that we have a process ptid. */
475 ptid_t process_ptid = pid_to_ptid (ptid_get_pid (child_ptid));
477 target_terminal::ours_for_output ();
478 fprintf_filtered (gdb_stdlog,
479 _("Detaching after %s from child %s.\n"),
480 has_vforked ? "vfork" : "fork",
481 target_pid_to_str (process_ptid));
486 struct inferior *parent_inf, *child_inf;
488 /* Add process to GDB's tables. */
489 child_inf = add_inferior (ptid_get_pid (child_ptid));
491 parent_inf = current_inferior ();
492 child_inf->attach_flag = parent_inf->attach_flag;
493 copy_terminal_info (child_inf, parent_inf);
494 child_inf->gdbarch = parent_inf->gdbarch;
495 copy_inferior_target_desc_info (child_inf, parent_inf);
497 scoped_restore_current_pspace_and_thread restore_pspace_thread;
499 inferior_ptid = child_ptid;
500 add_thread (inferior_ptid);
501 set_current_inferior (child_inf);
502 child_inf->symfile_flags = SYMFILE_NO_READ;
504 /* If this is a vfork child, then the address-space is
505 shared with the parent. */
508 child_inf->pspace = parent_inf->pspace;
509 child_inf->aspace = parent_inf->aspace;
511 /* The parent will be frozen until the child is done
512 with the shared region. Keep track of the
514 child_inf->vfork_parent = parent_inf;
515 child_inf->pending_detach = 0;
516 parent_inf->vfork_child = child_inf;
517 parent_inf->pending_detach = 0;
521 child_inf->aspace = new_address_space ();
522 child_inf->pspace = add_program_space (child_inf->aspace);
523 child_inf->removable = 1;
524 set_current_program_space (child_inf->pspace);
525 clone_program_space (child_inf->pspace, parent_inf->pspace);
527 /* Let the shared library layer (e.g., solib-svr4) learn
528 about this new process, relocate the cloned exec, pull
529 in shared libraries, and install the solib event
530 breakpoint. If a "cloned-VM" event was propagated
531 better throughout the core, this wouldn't be
533 solib_create_inferior_hook (0);
539 struct inferior *parent_inf;
541 parent_inf = current_inferior ();
543 /* If we detached from the child, then we have to be careful
544 to not insert breakpoints in the parent until the child
545 is done with the shared memory region. However, if we're
546 staying attached to the child, then we can and should
547 insert breakpoints, so that we can debug it. A
548 subsequent child exec or exit is enough to know when does
549 the child stops using the parent's address space. */
550 parent_inf->waiting_for_vfork_done = detach_fork;
551 parent_inf->pspace->breakpoints_not_allowed = detach_fork;
556 /* Follow the child. */
557 struct inferior *parent_inf, *child_inf;
558 struct program_space *parent_pspace;
560 if (info_verbose || debug_infrun)
562 target_terminal::ours_for_output ();
563 fprintf_filtered (gdb_stdlog,
564 _("Attaching after %s %s to child %s.\n"),
565 target_pid_to_str (parent_ptid),
566 has_vforked ? "vfork" : "fork",
567 target_pid_to_str (child_ptid));
570 /* Add the new inferior first, so that the target_detach below
571 doesn't unpush the target. */
573 child_inf = add_inferior (ptid_get_pid (child_ptid));
575 parent_inf = current_inferior ();
576 child_inf->attach_flag = parent_inf->attach_flag;
577 copy_terminal_info (child_inf, parent_inf);
578 child_inf->gdbarch = parent_inf->gdbarch;
579 copy_inferior_target_desc_info (child_inf, parent_inf);
581 parent_pspace = parent_inf->pspace;
583 /* If we're vforking, we want to hold on to the parent until the
584 child exits or execs. At child exec or exit time we can
585 remove the old breakpoints from the parent and detach or
586 resume debugging it. Otherwise, detach the parent now; we'll
587 want to reuse it's program/address spaces, but we can't set
588 them to the child before removing breakpoints from the
589 parent, otherwise, the breakpoints module could decide to
590 remove breakpoints from the wrong process (since they'd be
591 assigned to the same address space). */
595 gdb_assert (child_inf->vfork_parent == NULL);
596 gdb_assert (parent_inf->vfork_child == NULL);
597 child_inf->vfork_parent = parent_inf;
598 child_inf->pending_detach = 0;
599 parent_inf->vfork_child = child_inf;
600 parent_inf->pending_detach = detach_fork;
601 parent_inf->waiting_for_vfork_done = 0;
603 else if (detach_fork)
605 if (info_verbose || debug_infrun)
607 /* Ensure that we have a process ptid. */
608 ptid_t process_ptid = pid_to_ptid (ptid_get_pid (child_ptid));
610 target_terminal::ours_for_output ();
611 fprintf_filtered (gdb_stdlog,
612 _("Detaching after fork from "
614 target_pid_to_str (process_ptid));
617 target_detach (NULL, 0);
620 /* Note that the detach above makes PARENT_INF dangling. */
622 /* Add the child thread to the appropriate lists, and switch to
623 this new thread, before cloning the program space, and
624 informing the solib layer about this new process. */
626 inferior_ptid = child_ptid;
627 add_thread (inferior_ptid);
628 set_current_inferior (child_inf);
630 /* If this is a vfork child, then the address-space is shared
631 with the parent. If we detached from the parent, then we can
632 reuse the parent's program/address spaces. */
633 if (has_vforked || detach_fork)
635 child_inf->pspace = parent_pspace;
636 child_inf->aspace = child_inf->pspace->aspace;
640 child_inf->aspace = new_address_space ();
641 child_inf->pspace = add_program_space (child_inf->aspace);
642 child_inf->removable = 1;
643 child_inf->symfile_flags = SYMFILE_NO_READ;
644 set_current_program_space (child_inf->pspace);
645 clone_program_space (child_inf->pspace, parent_pspace);
647 /* Let the shared library layer (e.g., solib-svr4) learn
648 about this new process, relocate the cloned exec, pull in
649 shared libraries, and install the solib event breakpoint.
650 If a "cloned-VM" event was propagated better throughout
651 the core, this wouldn't be required. */
652 solib_create_inferior_hook (0);
656 return target_follow_fork (follow_child, detach_fork);
659 /* Tell the target to follow the fork we're stopped at. Returns true
660 if the inferior should be resumed; false, if the target for some
661 reason decided it's best not to resume. */
666 int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
667 int should_resume = 1;
668 struct thread_info *tp;
670 /* Copy user stepping state to the new inferior thread. FIXME: the
671 followed fork child thread should have a copy of most of the
672 parent thread structure's run control related fields, not just these.
673 Initialized to avoid "may be used uninitialized" warnings from gcc. */
674 struct breakpoint *step_resume_breakpoint = NULL;
675 struct breakpoint *exception_resume_breakpoint = NULL;
676 CORE_ADDR step_range_start = 0;
677 CORE_ADDR step_range_end = 0;
678 struct frame_id step_frame_id = { 0 };
679 struct thread_fsm *thread_fsm = NULL;
684 struct target_waitstatus wait_status;
686 /* Get the last target status returned by target_wait(). */
687 get_last_target_status (&wait_ptid, &wait_status);
689 /* If not stopped at a fork event, then there's nothing else to
691 if (wait_status.kind != TARGET_WAITKIND_FORKED
692 && wait_status.kind != TARGET_WAITKIND_VFORKED)
695 /* Check if we switched over from WAIT_PTID, since the event was
697 if (!ptid_equal (wait_ptid, minus_one_ptid)
698 && !ptid_equal (inferior_ptid, wait_ptid))
700 /* We did. Switch back to WAIT_PTID thread, to tell the
701 target to follow it (in either direction). We'll
702 afterwards refuse to resume, and inform the user what
704 switch_to_thread (wait_ptid);
709 tp = inferior_thread ();
711 /* If there were any forks/vforks that were caught and are now to be
712 followed, then do so now. */
713 switch (tp->pending_follow.kind)
715 case TARGET_WAITKIND_FORKED:
716 case TARGET_WAITKIND_VFORKED:
718 ptid_t parent, child;
720 /* If the user did a next/step, etc, over a fork call,
721 preserve the stepping state in the fork child. */
722 if (follow_child && should_resume)
724 step_resume_breakpoint = clone_momentary_breakpoint
725 (tp->control.step_resume_breakpoint);
726 step_range_start = tp->control.step_range_start;
727 step_range_end = tp->control.step_range_end;
728 step_frame_id = tp->control.step_frame_id;
729 exception_resume_breakpoint
730 = clone_momentary_breakpoint (tp->control.exception_resume_breakpoint);
731 thread_fsm = tp->thread_fsm;
733 /* For now, delete the parent's sr breakpoint, otherwise,
734 parent/child sr breakpoints are considered duplicates,
735 and the child version will not be installed. Remove
736 this when the breakpoints module becomes aware of
737 inferiors and address spaces. */
738 delete_step_resume_breakpoint (tp);
739 tp->control.step_range_start = 0;
740 tp->control.step_range_end = 0;
741 tp->control.step_frame_id = null_frame_id;
742 delete_exception_resume_breakpoint (tp);
743 tp->thread_fsm = NULL;
746 parent = inferior_ptid;
747 child = tp->pending_follow.value.related_pid;
749 /* Set up inferior(s) as specified by the caller, and tell the
750 target to do whatever is necessary to follow either parent
752 if (follow_fork_inferior (follow_child, detach_fork))
754 /* Target refused to follow, or there's some other reason
755 we shouldn't resume. */
760 /* This pending follow fork event is now handled, one way
761 or another. The previous selected thread may be gone
762 from the lists by now, but if it is still around, need
763 to clear the pending follow request. */
764 tp = find_thread_ptid (parent);
766 tp->pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
768 /* This makes sure we don't try to apply the "Switched
769 over from WAIT_PID" logic above. */
770 nullify_last_target_wait_ptid ();
772 /* If we followed the child, switch to it... */
775 switch_to_thread (child);
777 /* ... and preserve the stepping state, in case the
778 user was stepping over the fork call. */
781 tp = inferior_thread ();
782 tp->control.step_resume_breakpoint
783 = step_resume_breakpoint;
784 tp->control.step_range_start = step_range_start;
785 tp->control.step_range_end = step_range_end;
786 tp->control.step_frame_id = step_frame_id;
787 tp->control.exception_resume_breakpoint
788 = exception_resume_breakpoint;
789 tp->thread_fsm = thread_fsm;
793 /* If we get here, it was because we're trying to
794 resume from a fork catchpoint, but, the user
795 has switched threads away from the thread that
796 forked. In that case, the resume command
797 issued is most likely not applicable to the
798 child, so just warn, and refuse to resume. */
799 warning (_("Not resuming: switched threads "
800 "before following fork child."));
803 /* Reset breakpoints in the child as appropriate. */
804 follow_inferior_reset_breakpoints ();
807 switch_to_thread (parent);
811 case TARGET_WAITKIND_SPURIOUS:
812 /* Nothing to follow. */
815 internal_error (__FILE__, __LINE__,
816 "Unexpected pending_follow.kind %d\n",
817 tp->pending_follow.kind);
821 return should_resume;
825 follow_inferior_reset_breakpoints (void)
827 struct thread_info *tp = inferior_thread ();
829 /* Was there a step_resume breakpoint? (There was if the user
830 did a "next" at the fork() call.) If so, explicitly reset its
831 thread number. Cloned step_resume breakpoints are disabled on
832 creation, so enable it here now that it is associated with the
835 step_resumes are a form of bp that are made to be per-thread.
836 Since we created the step_resume bp when the parent process
837 was being debugged, and now are switching to the child process,
838 from the breakpoint package's viewpoint, that's a switch of
839 "threads". We must update the bp's notion of which thread
840 it is for, or it'll be ignored when it triggers. */
842 if (tp->control.step_resume_breakpoint)
844 breakpoint_re_set_thread (tp->control.step_resume_breakpoint);
845 tp->control.step_resume_breakpoint->loc->enabled = 1;
848 /* Treat exception_resume breakpoints like step_resume breakpoints. */
849 if (tp->control.exception_resume_breakpoint)
851 breakpoint_re_set_thread (tp->control.exception_resume_breakpoint);
852 tp->control.exception_resume_breakpoint->loc->enabled = 1;
855 /* Reinsert all breakpoints in the child. The user may have set
856 breakpoints after catching the fork, in which case those
857 were never set in the child, but only in the parent. This makes
858 sure the inserted breakpoints match the breakpoint list. */
860 breakpoint_re_set ();
861 insert_breakpoints ();
864 /* The child has exited or execed: resume threads of the parent the
865 user wanted to be executing. */
868 proceed_after_vfork_done (struct thread_info *thread,
871 int pid = * (int *) arg;
873 if (ptid_get_pid (thread->ptid) == pid
874 && is_running (thread->ptid)
875 && !is_executing (thread->ptid)
876 && !thread->stop_requested
877 && thread->suspend.stop_signal == GDB_SIGNAL_0)
880 fprintf_unfiltered (gdb_stdlog,
881 "infrun: resuming vfork parent thread %s\n",
882 target_pid_to_str (thread->ptid));
884 switch_to_thread (thread->ptid);
885 clear_proceed_status (0);
886 proceed ((CORE_ADDR) -1, GDB_SIGNAL_DEFAULT);
892 /* Save/restore inferior_ptid, current program space and current
893 inferior. Only use this if the current context points at an exited
894 inferior (and therefore there's no current thread to save). */
895 class scoped_restore_exited_inferior
898 scoped_restore_exited_inferior ()
899 : m_saved_ptid (&inferior_ptid)
903 scoped_restore_tmpl<ptid_t> m_saved_ptid;
904 scoped_restore_current_program_space m_pspace;
905 scoped_restore_current_inferior m_inferior;
908 /* Called whenever we notice an exec or exit event, to handle
909 detaching or resuming a vfork parent. */
912 handle_vfork_child_exec_or_exit (int exec)
914 struct inferior *inf = current_inferior ();
916 if (inf->vfork_parent)
918 int resume_parent = -1;
920 /* This exec or exit marks the end of the shared memory region
921 between the parent and the child. If the user wanted to
922 detach from the parent, now is the time. */
924 if (inf->vfork_parent->pending_detach)
926 struct thread_info *tp;
927 struct program_space *pspace;
928 struct address_space *aspace;
930 /* follow-fork child, detach-on-fork on. */
932 inf->vfork_parent->pending_detach = 0;
934 gdb::optional<scoped_restore_exited_inferior>
935 maybe_restore_inferior;
936 gdb::optional<scoped_restore_current_pspace_and_thread>
937 maybe_restore_thread;
939 /* If we're handling a child exit, then inferior_ptid points
940 at the inferior's pid, not to a thread. */
942 maybe_restore_inferior.emplace ();
944 maybe_restore_thread.emplace ();
946 /* We're letting loose of the parent. */
947 tp = any_live_thread_of_process (inf->vfork_parent->pid);
948 switch_to_thread (tp->ptid);
950 /* We're about to detach from the parent, which implicitly
951 removes breakpoints from its address space. There's a
952 catch here: we want to reuse the spaces for the child,
953 but, parent/child are still sharing the pspace at this
954 point, although the exec in reality makes the kernel give
955 the child a fresh set of new pages. The problem here is
956 that the breakpoints module being unaware of this, would
957 likely chose the child process to write to the parent
958 address space. Swapping the child temporarily away from
959 the spaces has the desired effect. Yes, this is "sort
962 pspace = inf->pspace;
963 aspace = inf->aspace;
967 if (debug_infrun || info_verbose)
969 target_terminal::ours_for_output ();
973 fprintf_filtered (gdb_stdlog,
974 _("Detaching vfork parent process "
975 "%d after child exec.\n"),
976 inf->vfork_parent->pid);
980 fprintf_filtered (gdb_stdlog,
981 _("Detaching vfork parent process "
982 "%d after child exit.\n"),
983 inf->vfork_parent->pid);
987 target_detach (NULL, 0);
990 inf->pspace = pspace;
991 inf->aspace = aspace;
995 /* We're staying attached to the parent, so, really give the
996 child a new address space. */
997 inf->pspace = add_program_space (maybe_new_address_space ());
998 inf->aspace = inf->pspace->aspace;
1000 set_current_program_space (inf->pspace);
1002 resume_parent = inf->vfork_parent->pid;
1004 /* Break the bonds. */
1005 inf->vfork_parent->vfork_child = NULL;
1009 struct program_space *pspace;
1011 /* If this is a vfork child exiting, then the pspace and
1012 aspaces were shared with the parent. Since we're
1013 reporting the process exit, we'll be mourning all that is
1014 found in the address space, and switching to null_ptid,
1015 preparing to start a new inferior. But, since we don't
1016 want to clobber the parent's address/program spaces, we
1017 go ahead and create a new one for this exiting
1020 /* Switch to null_ptid while running clone_program_space, so
1021 that clone_program_space doesn't want to read the
1022 selected frame of a dead process. */
1023 scoped_restore restore_ptid
1024 = make_scoped_restore (&inferior_ptid, null_ptid);
1026 /* This inferior is dead, so avoid giving the breakpoints
1027 module the option to write through to it (cloning a
1028 program space resets breakpoints). */
1031 pspace = add_program_space (maybe_new_address_space ());
1032 set_current_program_space (pspace);
1034 inf->symfile_flags = SYMFILE_NO_READ;
1035 clone_program_space (pspace, inf->vfork_parent->pspace);
1036 inf->pspace = pspace;
1037 inf->aspace = pspace->aspace;
1039 resume_parent = inf->vfork_parent->pid;
1040 /* Break the bonds. */
1041 inf->vfork_parent->vfork_child = NULL;
1044 inf->vfork_parent = NULL;
1046 gdb_assert (current_program_space == inf->pspace);
1048 if (non_stop && resume_parent != -1)
1050 /* If the user wanted the parent to be running, let it go
1052 scoped_restore_current_thread restore_thread;
1055 fprintf_unfiltered (gdb_stdlog,
1056 "infrun: resuming vfork parent process %d\n",
1059 iterate_over_threads (proceed_after_vfork_done, &resume_parent);
1064 /* Enum strings for "set|show follow-exec-mode". */
1066 static const char follow_exec_mode_new[] = "new";
1067 static const char follow_exec_mode_same[] = "same";
1068 static const char *const follow_exec_mode_names[] =
1070 follow_exec_mode_new,
1071 follow_exec_mode_same,
1075 static const char *follow_exec_mode_string = follow_exec_mode_same;
1077 show_follow_exec_mode_string (struct ui_file *file, int from_tty,
1078 struct cmd_list_element *c, const char *value)
1080 fprintf_filtered (file, _("Follow exec mode is \"%s\".\n"), value);
1083 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1086 follow_exec (ptid_t ptid, char *exec_file_target)
1088 struct thread_info *th, *tmp;
1089 struct inferior *inf = current_inferior ();
1090 int pid = ptid_get_pid (ptid);
1091 ptid_t process_ptid;
1092 char *exec_file_host;
1093 struct cleanup *old_chain;
1095 /* This is an exec event that we actually wish to pay attention to.
1096 Refresh our symbol table to the newly exec'd program, remove any
1097 momentary bp's, etc.
1099 If there are breakpoints, they aren't really inserted now,
1100 since the exec() transformed our inferior into a fresh set
1103 We want to preserve symbolic breakpoints on the list, since
1104 we have hopes that they can be reset after the new a.out's
1105 symbol table is read.
1107 However, any "raw" breakpoints must be removed from the list
1108 (e.g., the solib bp's), since their address is probably invalid
1111 And, we DON'T want to call delete_breakpoints() here, since
1112 that may write the bp's "shadow contents" (the instruction
1113 value that was overwritten witha TRAP instruction). Since
1114 we now have a new a.out, those shadow contents aren't valid. */
1116 mark_breakpoints_out ();
1118 /* The target reports the exec event to the main thread, even if
1119 some other thread does the exec, and even if the main thread was
1120 stopped or already gone. We may still have non-leader threads of
1121 the process on our list. E.g., on targets that don't have thread
1122 exit events (like remote); or on native Linux in non-stop mode if
1123 there were only two threads in the inferior and the non-leader
1124 one is the one that execs (and nothing forces an update of the
1125 thread list up to here). When debugging remotely, it's best to
1126 avoid extra traffic, when possible, so avoid syncing the thread
1127 list with the target, and instead go ahead and delete all threads
1128 of the process but one that reported the event. Note this must
1129 be done before calling update_breakpoints_after_exec, as
1130 otherwise clearing the threads' resources would reference stale
1131 thread breakpoints -- it may have been one of these threads that
1132 stepped across the exec. We could just clear their stepping
1133 states, but as long as we're iterating, might as well delete
1134 them. Deleting them now rather than at the next user-visible
1135 stop provides a nicer sequence of events for user and MI
1137 ALL_THREADS_SAFE (th, tmp)
1138 if (ptid_get_pid (th->ptid) == pid && !ptid_equal (th->ptid, ptid))
1139 delete_thread (th->ptid);
1141 /* We also need to clear any left over stale state for the
1142 leader/event thread. E.g., if there was any step-resume
1143 breakpoint or similar, it's gone now. We cannot truly
1144 step-to-next statement through an exec(). */
1145 th = inferior_thread ();
1146 th->control.step_resume_breakpoint = NULL;
1147 th->control.exception_resume_breakpoint = NULL;
1148 th->control.single_step_breakpoints = NULL;
1149 th->control.step_range_start = 0;
1150 th->control.step_range_end = 0;
1152 /* The user may have had the main thread held stopped in the
1153 previous image (e.g., schedlock on, or non-stop). Release
1155 th->stop_requested = 0;
1157 update_breakpoints_after_exec ();
1159 /* What is this a.out's name? */
1160 process_ptid = pid_to_ptid (pid);
1161 printf_unfiltered (_("%s is executing new program: %s\n"),
1162 target_pid_to_str (process_ptid),
1165 /* We've followed the inferior through an exec. Therefore, the
1166 inferior has essentially been killed & reborn. */
1168 gdb_flush (gdb_stdout);
1170 breakpoint_init_inferior (inf_execd);
1172 exec_file_host = exec_file_find (exec_file_target, NULL);
1173 old_chain = make_cleanup (xfree, exec_file_host);
1175 /* If we were unable to map the executable target pathname onto a host
1176 pathname, tell the user that. Otherwise GDB's subsequent behavior
1177 is confusing. Maybe it would even be better to stop at this point
1178 so that the user can specify a file manually before continuing. */
1179 if (exec_file_host == NULL)
1180 warning (_("Could not load symbols for executable %s.\n"
1181 "Do you need \"set sysroot\"?"),
1184 /* Reset the shared library package. This ensures that we get a
1185 shlib event when the child reaches "_start", at which point the
1186 dld will have had a chance to initialize the child. */
1187 /* Also, loading a symbol file below may trigger symbol lookups, and
1188 we don't want those to be satisfied by the libraries of the
1189 previous incarnation of this process. */
1190 no_shared_libraries (NULL, 0);
1192 if (follow_exec_mode_string == follow_exec_mode_new)
1194 /* The user wants to keep the old inferior and program spaces
1195 around. Create a new fresh one, and switch to it. */
1197 /* Do exit processing for the original inferior before adding
1198 the new inferior so we don't have two active inferiors with
1199 the same ptid, which can confuse find_inferior_ptid. */
1200 exit_inferior_num_silent (current_inferior ()->num);
1202 inf = add_inferior_with_spaces ();
1204 target_follow_exec (inf, exec_file_target);
1206 set_current_inferior (inf);
1207 set_current_program_space (inf->pspace);
1211 /* The old description may no longer be fit for the new image.
1212 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1213 old description; we'll read a new one below. No need to do
1214 this on "follow-exec-mode new", as the old inferior stays
1215 around (its description is later cleared/refetched on
1217 target_clear_description ();
1220 gdb_assert (current_program_space == inf->pspace);
1222 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1223 because the proper displacement for a PIE (Position Independent
1224 Executable) main symbol file will only be computed by
1225 solib_create_inferior_hook below. breakpoint_re_set would fail
1226 to insert the breakpoints with the zero displacement. */
1227 try_open_exec_file (exec_file_host, inf, SYMFILE_DEFER_BP_RESET);
1229 do_cleanups (old_chain);
1231 /* If the target can specify a description, read it. Must do this
1232 after flipping to the new executable (because the target supplied
1233 description must be compatible with the executable's
1234 architecture, and the old executable may e.g., be 32-bit, while
1235 the new one 64-bit), and before anything involving memory or
1237 target_find_description ();
1239 /* The add_thread call ends up reading registers, so do it after updating the
1240 target description. */
1241 if (follow_exec_mode_string == follow_exec_mode_new)
1244 solib_create_inferior_hook (0);
1246 jit_inferior_created_hook ();
1248 breakpoint_re_set ();
1250 /* Reinsert all breakpoints. (Those which were symbolic have
1251 been reset to the proper address in the new a.out, thanks
1252 to symbol_file_command...). */
1253 insert_breakpoints ();
1255 /* The next resume of this inferior should bring it to the shlib
1256 startup breakpoints. (If the user had also set bp's on
1257 "main" from the old (parent) process, then they'll auto-
1258 matically get reset there in the new process.). */
1261 /* The queue of threads that need to do a step-over operation to get
1262 past e.g., a breakpoint. What technique is used to step over the
1263 breakpoint/watchpoint does not matter -- all threads end up in the
1264 same queue, to maintain rough temporal order of execution, in order
1265 to avoid starvation, otherwise, we could e.g., find ourselves
1266 constantly stepping the same couple threads past their breakpoints
1267 over and over, if the single-step finish fast enough. */
1268 struct thread_info *step_over_queue_head;
1270 /* Bit flags indicating what the thread needs to step over. */
1272 enum step_over_what_flag
1274 /* Step over a breakpoint. */
1275 STEP_OVER_BREAKPOINT = 1,
1277 /* Step past a non-continuable watchpoint, in order to let the
1278 instruction execute so we can evaluate the watchpoint
1280 STEP_OVER_WATCHPOINT = 2
1282 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag, step_over_what);
1284 /* Info about an instruction that is being stepped over. */
1286 struct step_over_info
1288 /* If we're stepping past a breakpoint, this is the address space
1289 and address of the instruction the breakpoint is set at. We'll
1290 skip inserting all breakpoints here. Valid iff ASPACE is
1292 struct address_space *aspace;
1295 /* The instruction being stepped over triggers a nonsteppable
1296 watchpoint. If true, we'll skip inserting watchpoints. */
1297 int nonsteppable_watchpoint_p;
1299 /* The thread's global number. */
1303 /* The step-over info of the location that is being stepped over.
1305 Note that with async/breakpoint always-inserted mode, a user might
1306 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1307 being stepped over. As setting a new breakpoint inserts all
1308 breakpoints, we need to make sure the breakpoint being stepped over
1309 isn't inserted then. We do that by only clearing the step-over
1310 info when the step-over is actually finished (or aborted).
1312 Presently GDB can only step over one breakpoint at any given time.
1313 Given threads that can't run code in the same address space as the
1314 breakpoint's can't really miss the breakpoint, GDB could be taught
1315 to step-over at most one breakpoint per address space (so this info
1316 could move to the address space object if/when GDB is extended).
1317 The set of breakpoints being stepped over will normally be much
1318 smaller than the set of all breakpoints, so a flag in the
1319 breakpoint location structure would be wasteful. A separate list
1320 also saves complexity and run-time, as otherwise we'd have to go
1321 through all breakpoint locations clearing their flag whenever we
1322 start a new sequence. Similar considerations weigh against storing
1323 this info in the thread object. Plus, not all step overs actually
1324 have breakpoint locations -- e.g., stepping past a single-step
1325 breakpoint, or stepping to complete a non-continuable
1327 static struct step_over_info step_over_info;
1329 /* Record the address of the breakpoint/instruction we're currently
1331 N.B. We record the aspace and address now, instead of say just the thread,
1332 because when we need the info later the thread may be running. */
1335 set_step_over_info (struct address_space *aspace, CORE_ADDR address,
1336 int nonsteppable_watchpoint_p,
1339 step_over_info.aspace = aspace;
1340 step_over_info.address = address;
1341 step_over_info.nonsteppable_watchpoint_p = nonsteppable_watchpoint_p;
1342 step_over_info.thread = thread;
1345 /* Called when we're not longer stepping over a breakpoint / an
1346 instruction, so all breakpoints are free to be (re)inserted. */
1349 clear_step_over_info (void)
1352 fprintf_unfiltered (gdb_stdlog,
1353 "infrun: clear_step_over_info\n");
1354 step_over_info.aspace = NULL;
1355 step_over_info.address = 0;
1356 step_over_info.nonsteppable_watchpoint_p = 0;
1357 step_over_info.thread = -1;
1363 stepping_past_instruction_at (struct address_space *aspace,
1366 return (step_over_info.aspace != NULL
1367 && breakpoint_address_match (aspace, address,
1368 step_over_info.aspace,
1369 step_over_info.address));
1375 thread_is_stepping_over_breakpoint (int thread)
1377 return (step_over_info.thread != -1
1378 && thread == step_over_info.thread);
1384 stepping_past_nonsteppable_watchpoint (void)
1386 return step_over_info.nonsteppable_watchpoint_p;
1389 /* Returns true if step-over info is valid. */
1392 step_over_info_valid_p (void)
1394 return (step_over_info.aspace != NULL
1395 || stepping_past_nonsteppable_watchpoint ());
1399 /* Displaced stepping. */
1401 /* In non-stop debugging mode, we must take special care to manage
1402 breakpoints properly; in particular, the traditional strategy for
1403 stepping a thread past a breakpoint it has hit is unsuitable.
1404 'Displaced stepping' is a tactic for stepping one thread past a
1405 breakpoint it has hit while ensuring that other threads running
1406 concurrently will hit the breakpoint as they should.
1408 The traditional way to step a thread T off a breakpoint in a
1409 multi-threaded program in all-stop mode is as follows:
1411 a0) Initially, all threads are stopped, and breakpoints are not
1413 a1) We single-step T, leaving breakpoints uninserted.
1414 a2) We insert breakpoints, and resume all threads.
1416 In non-stop debugging, however, this strategy is unsuitable: we
1417 don't want to have to stop all threads in the system in order to
1418 continue or step T past a breakpoint. Instead, we use displaced
1421 n0) Initially, T is stopped, other threads are running, and
1422 breakpoints are inserted.
1423 n1) We copy the instruction "under" the breakpoint to a separate
1424 location, outside the main code stream, making any adjustments
1425 to the instruction, register, and memory state as directed by
1427 n2) We single-step T over the instruction at its new location.
1428 n3) We adjust the resulting register and memory state as directed
1429 by T's architecture. This includes resetting T's PC to point
1430 back into the main instruction stream.
1433 This approach depends on the following gdbarch methods:
1435 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1436 indicate where to copy the instruction, and how much space must
1437 be reserved there. We use these in step n1.
1439 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1440 address, and makes any necessary adjustments to the instruction,
1441 register contents, and memory. We use this in step n1.
1443 - gdbarch_displaced_step_fixup adjusts registers and memory after
1444 we have successfuly single-stepped the instruction, to yield the
1445 same effect the instruction would have had if we had executed it
1446 at its original address. We use this in step n3.
1448 - gdbarch_displaced_step_free_closure provides cleanup.
1450 The gdbarch_displaced_step_copy_insn and
1451 gdbarch_displaced_step_fixup functions must be written so that
1452 copying an instruction with gdbarch_displaced_step_copy_insn,
1453 single-stepping across the copied instruction, and then applying
1454 gdbarch_displaced_insn_fixup should have the same effects on the
1455 thread's memory and registers as stepping the instruction in place
1456 would have. Exactly which responsibilities fall to the copy and
1457 which fall to the fixup is up to the author of those functions.
1459 See the comments in gdbarch.sh for details.
1461 Note that displaced stepping and software single-step cannot
1462 currently be used in combination, although with some care I think
1463 they could be made to. Software single-step works by placing
1464 breakpoints on all possible subsequent instructions; if the
1465 displaced instruction is a PC-relative jump, those breakpoints
1466 could fall in very strange places --- on pages that aren't
1467 executable, or at addresses that are not proper instruction
1468 boundaries. (We do generally let other threads run while we wait
1469 to hit the software single-step breakpoint, and they might
1470 encounter such a corrupted instruction.) One way to work around
1471 this would be to have gdbarch_displaced_step_copy_insn fully
1472 simulate the effect of PC-relative instructions (and return NULL)
1473 on architectures that use software single-stepping.
1475 In non-stop mode, we can have independent and simultaneous step
1476 requests, so more than one thread may need to simultaneously step
1477 over a breakpoint. The current implementation assumes there is
1478 only one scratch space per process. In this case, we have to
1479 serialize access to the scratch space. If thread A wants to step
1480 over a breakpoint, but we are currently waiting for some other
1481 thread to complete a displaced step, we leave thread A stopped and
1482 place it in the displaced_step_request_queue. Whenever a displaced
1483 step finishes, we pick the next thread in the queue and start a new
1484 displaced step operation on it. See displaced_step_prepare and
1485 displaced_step_fixup for details. */
1487 /* Per-inferior displaced stepping state. */
1488 struct displaced_step_inferior_state
1490 /* Pointer to next in linked list. */
1491 struct displaced_step_inferior_state *next;
1493 /* The process this displaced step state refers to. */
1496 /* True if preparing a displaced step ever failed. If so, we won't
1497 try displaced stepping for this inferior again. */
1500 /* If this is not null_ptid, this is the thread carrying out a
1501 displaced single-step in process PID. This thread's state will
1502 require fixing up once it has completed its step. */
1505 /* The architecture the thread had when we stepped it. */
1506 struct gdbarch *step_gdbarch;
1508 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1509 for post-step cleanup. */
1510 struct displaced_step_closure *step_closure;
1512 /* The address of the original instruction, and the copy we
1514 CORE_ADDR step_original, step_copy;
1516 /* Saved contents of copy area. */
1517 gdb_byte *step_saved_copy;
1520 /* The list of states of processes involved in displaced stepping
1522 static struct displaced_step_inferior_state *displaced_step_inferior_states;
1524 /* Get the displaced stepping state of process PID. */
1526 static struct displaced_step_inferior_state *
1527 get_displaced_stepping_state (int pid)
1529 struct displaced_step_inferior_state *state;
1531 for (state = displaced_step_inferior_states;
1533 state = state->next)
1534 if (state->pid == pid)
1540 /* Returns true if any inferior has a thread doing a displaced
1544 displaced_step_in_progress_any_inferior (void)
1546 struct displaced_step_inferior_state *state;
1548 for (state = displaced_step_inferior_states;
1550 state = state->next)
1551 if (!ptid_equal (state->step_ptid, null_ptid))
1557 /* Return true if thread represented by PTID is doing a displaced
1561 displaced_step_in_progress_thread (ptid_t ptid)
1563 struct displaced_step_inferior_state *displaced;
1565 gdb_assert (!ptid_equal (ptid, null_ptid));
1567 displaced = get_displaced_stepping_state (ptid_get_pid (ptid));
1569 return (displaced != NULL && ptid_equal (displaced->step_ptid, ptid));
1572 /* Return true if process PID has a thread doing a displaced step. */
1575 displaced_step_in_progress (int pid)
1577 struct displaced_step_inferior_state *displaced;
1579 displaced = get_displaced_stepping_state (pid);
1580 if (displaced != NULL && !ptid_equal (displaced->step_ptid, null_ptid))
1586 /* Add a new displaced stepping state for process PID to the displaced
1587 stepping state list, or return a pointer to an already existing
1588 entry, if it already exists. Never returns NULL. */
1590 static struct displaced_step_inferior_state *
1591 add_displaced_stepping_state (int pid)
1593 struct displaced_step_inferior_state *state;
1595 for (state = displaced_step_inferior_states;
1597 state = state->next)
1598 if (state->pid == pid)
1601 state = XCNEW (struct displaced_step_inferior_state);
1603 state->next = displaced_step_inferior_states;
1604 displaced_step_inferior_states = state;
1609 /* If inferior is in displaced stepping, and ADDR equals to starting address
1610 of copy area, return corresponding displaced_step_closure. Otherwise,
1613 struct displaced_step_closure*
1614 get_displaced_step_closure_by_addr (CORE_ADDR addr)
1616 struct displaced_step_inferior_state *displaced
1617 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
1619 /* If checking the mode of displaced instruction in copy area. */
1620 if (displaced && !ptid_equal (displaced->step_ptid, null_ptid)
1621 && (displaced->step_copy == addr))
1622 return displaced->step_closure;
1627 /* Remove the displaced stepping state of process PID. */
1630 remove_displaced_stepping_state (int pid)
1632 struct displaced_step_inferior_state *it, **prev_next_p;
1634 gdb_assert (pid != 0);
1636 it = displaced_step_inferior_states;
1637 prev_next_p = &displaced_step_inferior_states;
1642 *prev_next_p = it->next;
1647 prev_next_p = &it->next;
1653 infrun_inferior_exit (struct inferior *inf)
1655 remove_displaced_stepping_state (inf->pid);
1658 /* If ON, and the architecture supports it, GDB will use displaced
1659 stepping to step over breakpoints. If OFF, or if the architecture
1660 doesn't support it, GDB will instead use the traditional
1661 hold-and-step approach. If AUTO (which is the default), GDB will
1662 decide which technique to use to step over breakpoints depending on
1663 which of all-stop or non-stop mode is active --- displaced stepping
1664 in non-stop mode; hold-and-step in all-stop mode. */
1666 static enum auto_boolean can_use_displaced_stepping = AUTO_BOOLEAN_AUTO;
1669 show_can_use_displaced_stepping (struct ui_file *file, int from_tty,
1670 struct cmd_list_element *c,
1673 if (can_use_displaced_stepping == AUTO_BOOLEAN_AUTO)
1674 fprintf_filtered (file,
1675 _("Debugger's willingness to use displaced stepping "
1676 "to step over breakpoints is %s (currently %s).\n"),
1677 value, target_is_non_stop_p () ? "on" : "off");
1679 fprintf_filtered (file,
1680 _("Debugger's willingness to use displaced stepping "
1681 "to step over breakpoints is %s.\n"), value);
1684 /* Return non-zero if displaced stepping can/should be used to step
1685 over breakpoints of thread TP. */
1688 use_displaced_stepping (struct thread_info *tp)
1690 struct regcache *regcache = get_thread_regcache (tp->ptid);
1691 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1692 struct displaced_step_inferior_state *displaced_state;
1694 displaced_state = get_displaced_stepping_state (ptid_get_pid (tp->ptid));
1696 return (((can_use_displaced_stepping == AUTO_BOOLEAN_AUTO
1697 && target_is_non_stop_p ())
1698 || can_use_displaced_stepping == AUTO_BOOLEAN_TRUE)
1699 && gdbarch_displaced_step_copy_insn_p (gdbarch)
1700 && find_record_target () == NULL
1701 && (displaced_state == NULL
1702 || !displaced_state->failed_before));
1705 /* Clean out any stray displaced stepping state. */
1707 displaced_step_clear (struct displaced_step_inferior_state *displaced)
1709 /* Indicate that there is no cleanup pending. */
1710 displaced->step_ptid = null_ptid;
1712 xfree (displaced->step_closure);
1713 displaced->step_closure = NULL;
1717 displaced_step_clear_cleanup (void *arg)
1719 struct displaced_step_inferior_state *state
1720 = (struct displaced_step_inferior_state *) arg;
1722 displaced_step_clear (state);
1725 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1727 displaced_step_dump_bytes (struct ui_file *file,
1728 const gdb_byte *buf,
1733 for (i = 0; i < len; i++)
1734 fprintf_unfiltered (file, "%02x ", buf[i]);
1735 fputs_unfiltered ("\n", file);
1738 /* Prepare to single-step, using displaced stepping.
1740 Note that we cannot use displaced stepping when we have a signal to
1741 deliver. If we have a signal to deliver and an instruction to step
1742 over, then after the step, there will be no indication from the
1743 target whether the thread entered a signal handler or ignored the
1744 signal and stepped over the instruction successfully --- both cases
1745 result in a simple SIGTRAP. In the first case we mustn't do a
1746 fixup, and in the second case we must --- but we can't tell which.
1747 Comments in the code for 'random signals' in handle_inferior_event
1748 explain how we handle this case instead.
1750 Returns 1 if preparing was successful -- this thread is going to be
1751 stepped now; 0 if displaced stepping this thread got queued; or -1
1752 if this instruction can't be displaced stepped. */
1755 displaced_step_prepare_throw (ptid_t ptid)
1757 struct cleanup *ignore_cleanups;
1758 struct thread_info *tp = find_thread_ptid (ptid);
1759 struct regcache *regcache = get_thread_regcache (ptid);
1760 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1761 struct address_space *aspace = get_regcache_aspace (regcache);
1762 CORE_ADDR original, copy;
1764 struct displaced_step_closure *closure;
1765 struct displaced_step_inferior_state *displaced;
1768 /* We should never reach this function if the architecture does not
1769 support displaced stepping. */
1770 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch));
1772 /* Nor if the thread isn't meant to step over a breakpoint. */
1773 gdb_assert (tp->control.trap_expected);
1775 /* Disable range stepping while executing in the scratch pad. We
1776 want a single-step even if executing the displaced instruction in
1777 the scratch buffer lands within the stepping range (e.g., a
1779 tp->control.may_range_step = 0;
1781 /* We have to displaced step one thread at a time, as we only have
1782 access to a single scratch space per inferior. */
1784 displaced = add_displaced_stepping_state (ptid_get_pid (ptid));
1786 if (!ptid_equal (displaced->step_ptid, null_ptid))
1788 /* Already waiting for a displaced step to finish. Defer this
1789 request and place in queue. */
1791 if (debug_displaced)
1792 fprintf_unfiltered (gdb_stdlog,
1793 "displaced: deferring step of %s\n",
1794 target_pid_to_str (ptid));
1796 thread_step_over_chain_enqueue (tp);
1801 if (debug_displaced)
1802 fprintf_unfiltered (gdb_stdlog,
1803 "displaced: stepping %s now\n",
1804 target_pid_to_str (ptid));
1807 displaced_step_clear (displaced);
1809 scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
1810 inferior_ptid = ptid;
1812 original = regcache_read_pc (regcache);
1814 copy = gdbarch_displaced_step_location (gdbarch);
1815 len = gdbarch_max_insn_length (gdbarch);
1817 if (breakpoint_in_range_p (aspace, copy, len))
1819 /* There's a breakpoint set in the scratch pad location range
1820 (which is usually around the entry point). We'd either
1821 install it before resuming, which would overwrite/corrupt the
1822 scratch pad, or if it was already inserted, this displaced
1823 step would overwrite it. The latter is OK in the sense that
1824 we already assume that no thread is going to execute the code
1825 in the scratch pad range (after initial startup) anyway, but
1826 the former is unacceptable. Simply punt and fallback to
1827 stepping over this breakpoint in-line. */
1828 if (debug_displaced)
1830 fprintf_unfiltered (gdb_stdlog,
1831 "displaced: breakpoint set in scratch pad. "
1832 "Stepping over breakpoint in-line instead.\n");
1838 /* Save the original contents of the copy area. */
1839 displaced->step_saved_copy = (gdb_byte *) xmalloc (len);
1840 ignore_cleanups = make_cleanup (free_current_contents,
1841 &displaced->step_saved_copy);
1842 status = target_read_memory (copy, displaced->step_saved_copy, len);
1844 throw_error (MEMORY_ERROR,
1845 _("Error accessing memory address %s (%s) for "
1846 "displaced-stepping scratch space."),
1847 paddress (gdbarch, copy), safe_strerror (status));
1848 if (debug_displaced)
1850 fprintf_unfiltered (gdb_stdlog, "displaced: saved %s: ",
1851 paddress (gdbarch, copy));
1852 displaced_step_dump_bytes (gdb_stdlog,
1853 displaced->step_saved_copy,
1857 closure = gdbarch_displaced_step_copy_insn (gdbarch,
1858 original, copy, regcache);
1859 if (closure == NULL)
1861 /* The architecture doesn't know how or want to displaced step
1862 this instruction or instruction sequence. Fallback to
1863 stepping over the breakpoint in-line. */
1864 do_cleanups (ignore_cleanups);
1868 /* Save the information we need to fix things up if the step
1870 displaced->step_ptid = ptid;
1871 displaced->step_gdbarch = gdbarch;
1872 displaced->step_closure = closure;
1873 displaced->step_original = original;
1874 displaced->step_copy = copy;
1876 make_cleanup (displaced_step_clear_cleanup, displaced);
1878 /* Resume execution at the copy. */
1879 regcache_write_pc (regcache, copy);
1881 discard_cleanups (ignore_cleanups);
1883 if (debug_displaced)
1884 fprintf_unfiltered (gdb_stdlog, "displaced: displaced pc to %s\n",
1885 paddress (gdbarch, copy));
1890 /* Wrapper for displaced_step_prepare_throw that disabled further
1891 attempts at displaced stepping if we get a memory error. */
1894 displaced_step_prepare (ptid_t ptid)
1900 prepared = displaced_step_prepare_throw (ptid);
1902 CATCH (ex, RETURN_MASK_ERROR)
1904 struct displaced_step_inferior_state *displaced_state;
1906 if (ex.error != MEMORY_ERROR
1907 && ex.error != NOT_SUPPORTED_ERROR)
1908 throw_exception (ex);
1912 fprintf_unfiltered (gdb_stdlog,
1913 "infrun: disabling displaced stepping: %s\n",
1917 /* Be verbose if "set displaced-stepping" is "on", silent if
1919 if (can_use_displaced_stepping == AUTO_BOOLEAN_TRUE)
1921 warning (_("disabling displaced stepping: %s"),
1925 /* Disable further displaced stepping attempts. */
1927 = get_displaced_stepping_state (ptid_get_pid (ptid));
1928 displaced_state->failed_before = 1;
1936 write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr,
1937 const gdb_byte *myaddr, int len)
1939 scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
1941 inferior_ptid = ptid;
1942 write_memory (memaddr, myaddr, len);
1945 /* Restore the contents of the copy area for thread PTID. */
1948 displaced_step_restore (struct displaced_step_inferior_state *displaced,
1951 ULONGEST len = gdbarch_max_insn_length (displaced->step_gdbarch);
1953 write_memory_ptid (ptid, displaced->step_copy,
1954 displaced->step_saved_copy, len);
1955 if (debug_displaced)
1956 fprintf_unfiltered (gdb_stdlog, "displaced: restored %s %s\n",
1957 target_pid_to_str (ptid),
1958 paddress (displaced->step_gdbarch,
1959 displaced->step_copy));
1962 /* If we displaced stepped an instruction successfully, adjust
1963 registers and memory to yield the same effect the instruction would
1964 have had if we had executed it at its original address, and return
1965 1. If the instruction didn't complete, relocate the PC and return
1966 -1. If the thread wasn't displaced stepping, return 0. */
1969 displaced_step_fixup (ptid_t event_ptid, enum gdb_signal signal)
1971 struct cleanup *old_cleanups;
1972 struct displaced_step_inferior_state *displaced
1973 = get_displaced_stepping_state (ptid_get_pid (event_ptid));
1976 /* Was any thread of this process doing a displaced step? */
1977 if (displaced == NULL)
1980 /* Was this event for the pid we displaced? */
1981 if (ptid_equal (displaced->step_ptid, null_ptid)
1982 || ! ptid_equal (displaced->step_ptid, event_ptid))
1985 old_cleanups = make_cleanup (displaced_step_clear_cleanup, displaced);
1987 displaced_step_restore (displaced, displaced->step_ptid);
1989 /* Fixup may need to read memory/registers. Switch to the thread
1990 that we're fixing up. Also, target_stopped_by_watchpoint checks
1991 the current thread. */
1992 switch_to_thread (event_ptid);
1994 /* Did the instruction complete successfully? */
1995 if (signal == GDB_SIGNAL_TRAP
1996 && !(target_stopped_by_watchpoint ()
1997 && (gdbarch_have_nonsteppable_watchpoint (displaced->step_gdbarch)
1998 || target_have_steppable_watchpoint)))
2000 /* Fix up the resulting state. */
2001 gdbarch_displaced_step_fixup (displaced->step_gdbarch,
2002 displaced->step_closure,
2003 displaced->step_original,
2004 displaced->step_copy,
2005 get_thread_regcache (displaced->step_ptid));
2010 /* Since the instruction didn't complete, all we can do is
2012 struct regcache *regcache = get_thread_regcache (event_ptid);
2013 CORE_ADDR pc = regcache_read_pc (regcache);
2015 pc = displaced->step_original + (pc - displaced->step_copy);
2016 regcache_write_pc (regcache, pc);
2020 do_cleanups (old_cleanups);
2022 displaced->step_ptid = null_ptid;
2027 /* Data to be passed around while handling an event. This data is
2028 discarded between events. */
2029 struct execution_control_state
2032 /* The thread that got the event, if this was a thread event; NULL
2034 struct thread_info *event_thread;
2036 struct target_waitstatus ws;
2037 int stop_func_filled_in;
2038 CORE_ADDR stop_func_start;
2039 CORE_ADDR stop_func_end;
2040 const char *stop_func_name;
2043 /* True if the event thread hit the single-step breakpoint of
2044 another thread. Thus the event doesn't cause a stop, the thread
2045 needs to be single-stepped past the single-step breakpoint before
2046 we can switch back to the original stepping thread. */
2047 int hit_singlestep_breakpoint;
2050 /* Clear ECS and set it to point at TP. */
2053 reset_ecs (struct execution_control_state *ecs, struct thread_info *tp)
2055 memset (ecs, 0, sizeof (*ecs));
2056 ecs->event_thread = tp;
2057 ecs->ptid = tp->ptid;
2060 static void keep_going_pass_signal (struct execution_control_state *ecs);
2061 static void prepare_to_wait (struct execution_control_state *ecs);
2062 static int keep_going_stepped_thread (struct thread_info *tp);
2063 static step_over_what thread_still_needs_step_over (struct thread_info *tp);
2065 /* Are there any pending step-over requests? If so, run all we can
2066 now and return true. Otherwise, return false. */
2069 start_step_over (void)
2071 struct thread_info *tp, *next;
2073 /* Don't start a new step-over if we already have an in-line
2074 step-over operation ongoing. */
2075 if (step_over_info_valid_p ())
2078 for (tp = step_over_queue_head; tp != NULL; tp = next)
2080 struct execution_control_state ecss;
2081 struct execution_control_state *ecs = &ecss;
2082 step_over_what step_what;
2083 int must_be_in_line;
2085 gdb_assert (!tp->stop_requested);
2087 next = thread_step_over_chain_next (tp);
2089 /* If this inferior already has a displaced step in process,
2090 don't start a new one. */
2091 if (displaced_step_in_progress (ptid_get_pid (tp->ptid)))
2094 step_what = thread_still_needs_step_over (tp);
2095 must_be_in_line = ((step_what & STEP_OVER_WATCHPOINT)
2096 || ((step_what & STEP_OVER_BREAKPOINT)
2097 && !use_displaced_stepping (tp)));
2099 /* We currently stop all threads of all processes to step-over
2100 in-line. If we need to start a new in-line step-over, let
2101 any pending displaced steps finish first. */
2102 if (must_be_in_line && displaced_step_in_progress_any_inferior ())
2105 thread_step_over_chain_remove (tp);
2107 if (step_over_queue_head == NULL)
2110 fprintf_unfiltered (gdb_stdlog,
2111 "infrun: step-over queue now empty\n");
2114 if (tp->control.trap_expected
2118 internal_error (__FILE__, __LINE__,
2119 "[%s] has inconsistent state: "
2120 "trap_expected=%d, resumed=%d, executing=%d\n",
2121 target_pid_to_str (tp->ptid),
2122 tp->control.trap_expected,
2128 fprintf_unfiltered (gdb_stdlog,
2129 "infrun: resuming [%s] for step-over\n",
2130 target_pid_to_str (tp->ptid));
2132 /* keep_going_pass_signal skips the step-over if the breakpoint
2133 is no longer inserted. In all-stop, we want to keep looking
2134 for a thread that needs a step-over instead of resuming TP,
2135 because we wouldn't be able to resume anything else until the
2136 target stops again. In non-stop, the resume always resumes
2137 only TP, so it's OK to let the thread resume freely. */
2138 if (!target_is_non_stop_p () && !step_what)
2141 switch_to_thread (tp->ptid);
2142 reset_ecs (ecs, tp);
2143 keep_going_pass_signal (ecs);
2145 if (!ecs->wait_some_more)
2146 error (_("Command aborted."));
2148 gdb_assert (tp->resumed);
2150 /* If we started a new in-line step-over, we're done. */
2151 if (step_over_info_valid_p ())
2153 gdb_assert (tp->control.trap_expected);
2157 if (!target_is_non_stop_p ())
2159 /* On all-stop, shouldn't have resumed unless we needed a
2161 gdb_assert (tp->control.trap_expected
2162 || tp->step_after_step_resume_breakpoint);
2164 /* With remote targets (at least), in all-stop, we can't
2165 issue any further remote commands until the program stops
2170 /* Either the thread no longer needed a step-over, or a new
2171 displaced stepping sequence started. Even in the latter
2172 case, continue looking. Maybe we can also start another
2173 displaced step on a thread of other process. */
2179 /* Update global variables holding ptids to hold NEW_PTID if they were
2180 holding OLD_PTID. */
2182 infrun_thread_ptid_changed (ptid_t old_ptid, ptid_t new_ptid)
2184 struct displaced_step_inferior_state *displaced;
2186 if (ptid_equal (inferior_ptid, old_ptid))
2187 inferior_ptid = new_ptid;
2189 for (displaced = displaced_step_inferior_states;
2191 displaced = displaced->next)
2193 if (ptid_equal (displaced->step_ptid, old_ptid))
2194 displaced->step_ptid = new_ptid;
2201 /* Things to clean up if we QUIT out of resume (). */
2203 resume_cleanups (void *ignore)
2205 if (!ptid_equal (inferior_ptid, null_ptid))
2206 delete_single_step_breakpoints (inferior_thread ());
2211 static const char schedlock_off[] = "off";
2212 static const char schedlock_on[] = "on";
2213 static const char schedlock_step[] = "step";
2214 static const char schedlock_replay[] = "replay";
2215 static const char *const scheduler_enums[] = {
2222 static const char *scheduler_mode = schedlock_replay;
2224 show_scheduler_mode (struct ui_file *file, int from_tty,
2225 struct cmd_list_element *c, const char *value)
2227 fprintf_filtered (file,
2228 _("Mode for locking scheduler "
2229 "during execution is \"%s\".\n"),
2234 set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
2236 if (!target_can_lock_scheduler)
2238 scheduler_mode = schedlock_off;
2239 error (_("Target '%s' cannot support this command."), target_shortname);
2243 /* True if execution commands resume all threads of all processes by
2244 default; otherwise, resume only threads of the current inferior
2246 int sched_multi = 0;
2248 /* Try to setup for software single stepping over the specified location.
2249 Return 1 if target_resume() should use hardware single step.
2251 GDBARCH the current gdbarch.
2252 PC the location to step over. */
2255 maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc)
2259 if (execution_direction == EXEC_FORWARD
2260 && gdbarch_software_single_step_p (gdbarch))
2261 hw_step = !insert_single_step_breakpoints (gdbarch);
2269 user_visible_resume_ptid (int step)
2275 /* With non-stop mode on, threads are always handled
2277 resume_ptid = inferior_ptid;
2279 else if ((scheduler_mode == schedlock_on)
2280 || (scheduler_mode == schedlock_step && step))
2282 /* User-settable 'scheduler' mode requires solo thread
2284 resume_ptid = inferior_ptid;
2286 else if ((scheduler_mode == schedlock_replay)
2287 && target_record_will_replay (minus_one_ptid, execution_direction))
2289 /* User-settable 'scheduler' mode requires solo thread resume in replay
2291 resume_ptid = inferior_ptid;
2293 else if (!sched_multi && target_supports_multi_process ())
2295 /* Resume all threads of the current process (and none of other
2297 resume_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
2301 /* Resume all threads of all processes. */
2302 resume_ptid = RESUME_ALL;
2308 /* Return a ptid representing the set of threads that we will resume,
2309 in the perspective of the target, assuming run control handling
2310 does not require leaving some threads stopped (e.g., stepping past
2311 breakpoint). USER_STEP indicates whether we're about to start the
2312 target for a stepping command. */
2315 internal_resume_ptid (int user_step)
2317 /* In non-stop, we always control threads individually. Note that
2318 the target may always work in non-stop mode even with "set
2319 non-stop off", in which case user_visible_resume_ptid could
2320 return a wildcard ptid. */
2321 if (target_is_non_stop_p ())
2322 return inferior_ptid;
2324 return user_visible_resume_ptid (user_step);
2327 /* Wrapper for target_resume, that handles infrun-specific
2331 do_target_resume (ptid_t resume_ptid, int step, enum gdb_signal sig)
2333 struct thread_info *tp = inferior_thread ();
2335 gdb_assert (!tp->stop_requested);
2337 /* Install inferior's terminal modes. */
2338 target_terminal::inferior ();
2340 /* Avoid confusing the next resume, if the next stop/resume
2341 happens to apply to another thread. */
2342 tp->suspend.stop_signal = GDB_SIGNAL_0;
2344 /* Advise target which signals may be handled silently.
2346 If we have removed breakpoints because we are stepping over one
2347 in-line (in any thread), we need to receive all signals to avoid
2348 accidentally skipping a breakpoint during execution of a signal
2351 Likewise if we're displaced stepping, otherwise a trap for a
2352 breakpoint in a signal handler might be confused with the
2353 displaced step finishing. We don't make the displaced_step_fixup
2354 step distinguish the cases instead, because:
2356 - a backtrace while stopped in the signal handler would show the
2357 scratch pad as frame older than the signal handler, instead of
2358 the real mainline code.
2360 - when the thread is later resumed, the signal handler would
2361 return to the scratch pad area, which would no longer be
2363 if (step_over_info_valid_p ()
2364 || displaced_step_in_progress (ptid_get_pid (tp->ptid)))
2365 target_pass_signals (0, NULL);
2367 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
2369 target_resume (resume_ptid, step, sig);
2371 target_commit_resume ();
2374 /* Resume the inferior, but allow a QUIT. This is useful if the user
2375 wants to interrupt some lengthy single-stepping operation
2376 (for child processes, the SIGINT goes to the inferior, and so
2377 we get a SIGINT random_signal, but for remote debugging and perhaps
2378 other targets, that's not true).
2380 SIG is the signal to give the inferior (zero for none). */
2382 resume (enum gdb_signal sig)
2384 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
2385 struct regcache *regcache = get_current_regcache ();
2386 struct gdbarch *gdbarch = get_regcache_arch (regcache);
2387 struct thread_info *tp = inferior_thread ();
2388 CORE_ADDR pc = regcache_read_pc (regcache);
2389 struct address_space *aspace = get_regcache_aspace (regcache);
2391 /* This represents the user's step vs continue request. When
2392 deciding whether "set scheduler-locking step" applies, it's the
2393 user's intention that counts. */
2394 const int user_step = tp->control.stepping_command;
2395 /* This represents what we'll actually request the target to do.
2396 This can decay from a step to a continue, if e.g., we need to
2397 implement single-stepping with breakpoints (software
2401 gdb_assert (!tp->stop_requested);
2402 gdb_assert (!thread_is_in_step_over_chain (tp));
2406 if (tp->suspend.waitstatus_pending_p)
2411 = target_waitstatus_to_string (&tp->suspend.waitstatus);
2413 fprintf_unfiltered (gdb_stdlog,
2414 "infrun: resume: thread %s has pending wait "
2415 "status %s (currently_stepping=%d).\n",
2416 target_pid_to_str (tp->ptid), statstr.c_str (),
2417 currently_stepping (tp));
2422 /* FIXME: What should we do if we are supposed to resume this
2423 thread with a signal? Maybe we should maintain a queue of
2424 pending signals to deliver. */
2425 if (sig != GDB_SIGNAL_0)
2427 warning (_("Couldn't deliver signal %s to %s."),
2428 gdb_signal_to_name (sig), target_pid_to_str (tp->ptid));
2431 tp->suspend.stop_signal = GDB_SIGNAL_0;
2432 discard_cleanups (old_cleanups);
2434 if (target_can_async_p ())
2439 tp->stepped_breakpoint = 0;
2441 /* Depends on stepped_breakpoint. */
2442 step = currently_stepping (tp);
2444 if (current_inferior ()->waiting_for_vfork_done)
2446 /* Don't try to single-step a vfork parent that is waiting for
2447 the child to get out of the shared memory region (by exec'ing
2448 or exiting). This is particularly important on software
2449 single-step archs, as the child process would trip on the
2450 software single step breakpoint inserted for the parent
2451 process. Since the parent will not actually execute any
2452 instruction until the child is out of the shared region (such
2453 are vfork's semantics), it is safe to simply continue it.
2454 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2455 the parent, and tell it to `keep_going', which automatically
2456 re-sets it stepping. */
2458 fprintf_unfiltered (gdb_stdlog,
2459 "infrun: resume : clear step\n");
2464 fprintf_unfiltered (gdb_stdlog,
2465 "infrun: resume (step=%d, signal=%s), "
2466 "trap_expected=%d, current thread [%s] at %s\n",
2467 step, gdb_signal_to_symbol_string (sig),
2468 tp->control.trap_expected,
2469 target_pid_to_str (inferior_ptid),
2470 paddress (gdbarch, pc));
2472 /* Normally, by the time we reach `resume', the breakpoints are either
2473 removed or inserted, as appropriate. The exception is if we're sitting
2474 at a permanent breakpoint; we need to step over it, but permanent
2475 breakpoints can't be removed. So we have to test for it here. */
2476 if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here)
2478 if (sig != GDB_SIGNAL_0)
2480 /* We have a signal to pass to the inferior. The resume
2481 may, or may not take us to the signal handler. If this
2482 is a step, we'll need to stop in the signal handler, if
2483 there's one, (if the target supports stepping into
2484 handlers), or in the next mainline instruction, if
2485 there's no handler. If this is a continue, we need to be
2486 sure to run the handler with all breakpoints inserted.
2487 In all cases, set a breakpoint at the current address
2488 (where the handler returns to), and once that breakpoint
2489 is hit, resume skipping the permanent breakpoint. If
2490 that breakpoint isn't hit, then we've stepped into the
2491 signal handler (or hit some other event). We'll delete
2492 the step-resume breakpoint then. */
2495 fprintf_unfiltered (gdb_stdlog,
2496 "infrun: resume: skipping permanent breakpoint, "
2497 "deliver signal first\n");
2499 clear_step_over_info ();
2500 tp->control.trap_expected = 0;
2502 if (tp->control.step_resume_breakpoint == NULL)
2504 /* Set a "high-priority" step-resume, as we don't want
2505 user breakpoints at PC to trigger (again) when this
2507 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2508 gdb_assert (tp->control.step_resume_breakpoint->loc->permanent);
2510 tp->step_after_step_resume_breakpoint = step;
2513 insert_breakpoints ();
2517 /* There's no signal to pass, we can go ahead and skip the
2518 permanent breakpoint manually. */
2520 fprintf_unfiltered (gdb_stdlog,
2521 "infrun: resume: skipping permanent breakpoint\n");
2522 gdbarch_skip_permanent_breakpoint (gdbarch, regcache);
2523 /* Update pc to reflect the new address from which we will
2524 execute instructions. */
2525 pc = regcache_read_pc (regcache);
2529 /* We've already advanced the PC, so the stepping part
2530 is done. Now we need to arrange for a trap to be
2531 reported to handle_inferior_event. Set a breakpoint
2532 at the current PC, and run to it. Don't update
2533 prev_pc, because if we end in
2534 switch_back_to_stepped_thread, we want the "expected
2535 thread advanced also" branch to be taken. IOW, we
2536 don't want this thread to step further from PC
2538 gdb_assert (!step_over_info_valid_p ());
2539 insert_single_step_breakpoint (gdbarch, aspace, pc);
2540 insert_breakpoints ();
2542 resume_ptid = internal_resume_ptid (user_step);
2543 do_target_resume (resume_ptid, 0, GDB_SIGNAL_0);
2544 discard_cleanups (old_cleanups);
2551 /* If we have a breakpoint to step over, make sure to do a single
2552 step only. Same if we have software watchpoints. */
2553 if (tp->control.trap_expected || bpstat_should_step ())
2554 tp->control.may_range_step = 0;
2556 /* If enabled, step over breakpoints by executing a copy of the
2557 instruction at a different address.
2559 We can't use displaced stepping when we have a signal to deliver;
2560 the comments for displaced_step_prepare explain why. The
2561 comments in the handle_inferior event for dealing with 'random
2562 signals' explain what we do instead.
2564 We can't use displaced stepping when we are waiting for vfork_done
2565 event, displaced stepping breaks the vfork child similarly as single
2566 step software breakpoint. */
2567 if (tp->control.trap_expected
2568 && use_displaced_stepping (tp)
2569 && !step_over_info_valid_p ()
2570 && sig == GDB_SIGNAL_0
2571 && !current_inferior ()->waiting_for_vfork_done)
2573 int prepared = displaced_step_prepare (inferior_ptid);
2578 fprintf_unfiltered (gdb_stdlog,
2579 "Got placed in step-over queue\n");
2581 tp->control.trap_expected = 0;
2582 discard_cleanups (old_cleanups);
2585 else if (prepared < 0)
2587 /* Fallback to stepping over the breakpoint in-line. */
2589 if (target_is_non_stop_p ())
2590 stop_all_threads ();
2592 set_step_over_info (get_regcache_aspace (regcache),
2593 regcache_read_pc (regcache), 0, tp->global_num);
2595 step = maybe_software_singlestep (gdbarch, pc);
2597 insert_breakpoints ();
2599 else if (prepared > 0)
2601 struct displaced_step_inferior_state *displaced;
2603 /* Update pc to reflect the new address from which we will
2604 execute instructions due to displaced stepping. */
2605 pc = regcache_read_pc (get_thread_regcache (inferior_ptid));
2607 displaced = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
2608 step = gdbarch_displaced_step_hw_singlestep (gdbarch,
2609 displaced->step_closure);
2613 /* Do we need to do it the hard way, w/temp breakpoints? */
2615 step = maybe_software_singlestep (gdbarch, pc);
2617 /* Currently, our software single-step implementation leads to different
2618 results than hardware single-stepping in one situation: when stepping
2619 into delivering a signal which has an associated signal handler,
2620 hardware single-step will stop at the first instruction of the handler,
2621 while software single-step will simply skip execution of the handler.
2623 For now, this difference in behavior is accepted since there is no
2624 easy way to actually implement single-stepping into a signal handler
2625 without kernel support.
2627 However, there is one scenario where this difference leads to follow-on
2628 problems: if we're stepping off a breakpoint by removing all breakpoints
2629 and then single-stepping. In this case, the software single-step
2630 behavior means that even if there is a *breakpoint* in the signal
2631 handler, GDB still would not stop.
2633 Fortunately, we can at least fix this particular issue. We detect
2634 here the case where we are about to deliver a signal while software
2635 single-stepping with breakpoints removed. In this situation, we
2636 revert the decisions to remove all breakpoints and insert single-
2637 step breakpoints, and instead we install a step-resume breakpoint
2638 at the current address, deliver the signal without stepping, and
2639 once we arrive back at the step-resume breakpoint, actually step
2640 over the breakpoint we originally wanted to step over. */
2641 if (thread_has_single_step_breakpoints_set (tp)
2642 && sig != GDB_SIGNAL_0
2643 && step_over_info_valid_p ())
2645 /* If we have nested signals or a pending signal is delivered
2646 immediately after a handler returns, might might already have
2647 a step-resume breakpoint set on the earlier handler. We cannot
2648 set another step-resume breakpoint; just continue on until the
2649 original breakpoint is hit. */
2650 if (tp->control.step_resume_breakpoint == NULL)
2652 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2653 tp->step_after_step_resume_breakpoint = 1;
2656 delete_single_step_breakpoints (tp);
2658 clear_step_over_info ();
2659 tp->control.trap_expected = 0;
2661 insert_breakpoints ();
2664 /* If STEP is set, it's a request to use hardware stepping
2665 facilities. But in that case, we should never
2666 use singlestep breakpoint. */
2667 gdb_assert (!(thread_has_single_step_breakpoints_set (tp) && step));
2669 /* Decide the set of threads to ask the target to resume. */
2670 if (tp->control.trap_expected)
2672 /* We're allowing a thread to run past a breakpoint it has
2673 hit, either by single-stepping the thread with the breakpoint
2674 removed, or by displaced stepping, with the breakpoint inserted.
2675 In the former case, we need to single-step only this thread,
2676 and keep others stopped, as they can miss this breakpoint if
2677 allowed to run. That's not really a problem for displaced
2678 stepping, but, we still keep other threads stopped, in case
2679 another thread is also stopped for a breakpoint waiting for
2680 its turn in the displaced stepping queue. */
2681 resume_ptid = inferior_ptid;
2684 resume_ptid = internal_resume_ptid (user_step);
2686 if (execution_direction != EXEC_REVERSE
2687 && step && breakpoint_inserted_here_p (aspace, pc))
2689 /* There are two cases where we currently need to step a
2690 breakpoint instruction when we have a signal to deliver:
2692 - See handle_signal_stop where we handle random signals that
2693 could take out us out of the stepping range. Normally, in
2694 that case we end up continuing (instead of stepping) over the
2695 signal handler with a breakpoint at PC, but there are cases
2696 where we should _always_ single-step, even if we have a
2697 step-resume breakpoint, like when a software watchpoint is
2698 set. Assuming single-stepping and delivering a signal at the
2699 same time would takes us to the signal handler, then we could
2700 have removed the breakpoint at PC to step over it. However,
2701 some hardware step targets (like e.g., Mac OS) can't step
2702 into signal handlers, and for those, we need to leave the
2703 breakpoint at PC inserted, as otherwise if the handler
2704 recurses and executes PC again, it'll miss the breakpoint.
2705 So we leave the breakpoint inserted anyway, but we need to
2706 record that we tried to step a breakpoint instruction, so
2707 that adjust_pc_after_break doesn't end up confused.
2709 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2710 in one thread after another thread that was stepping had been
2711 momentarily paused for a step-over. When we re-resume the
2712 stepping thread, it may be resumed from that address with a
2713 breakpoint that hasn't trapped yet. Seen with
2714 gdb.threads/non-stop-fair-events.exp, on targets that don't
2715 do displaced stepping. */
2718 fprintf_unfiltered (gdb_stdlog,
2719 "infrun: resume: [%s] stepped breakpoint\n",
2720 target_pid_to_str (tp->ptid));
2722 tp->stepped_breakpoint = 1;
2724 /* Most targets can step a breakpoint instruction, thus
2725 executing it normally. But if this one cannot, just
2726 continue and we will hit it anyway. */
2727 if (gdbarch_cannot_step_breakpoint (gdbarch))
2732 && tp->control.trap_expected
2733 && use_displaced_stepping (tp)
2734 && !step_over_info_valid_p ())
2736 struct regcache *resume_regcache = get_thread_regcache (tp->ptid);
2737 struct gdbarch *resume_gdbarch = get_regcache_arch (resume_regcache);
2738 CORE_ADDR actual_pc = regcache_read_pc (resume_regcache);
2741 fprintf_unfiltered (gdb_stdlog, "displaced: run %s: ",
2742 paddress (resume_gdbarch, actual_pc));
2743 read_memory (actual_pc, buf, sizeof (buf));
2744 displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
2747 if (tp->control.may_range_step)
2749 /* If we're resuming a thread with the PC out of the step
2750 range, then we're doing some nested/finer run control
2751 operation, like stepping the thread out of the dynamic
2752 linker or the displaced stepping scratch pad. We
2753 shouldn't have allowed a range step then. */
2754 gdb_assert (pc_in_thread_step_range (pc, tp));
2757 do_target_resume (resume_ptid, step, sig);
2759 discard_cleanups (old_cleanups);
2766 /* Counter that tracks number of user visible stops. This can be used
2767 to tell whether a command has proceeded the inferior past the
2768 current location. This allows e.g., inferior function calls in
2769 breakpoint commands to not interrupt the command list. When the
2770 call finishes successfully, the inferior is standing at the same
2771 breakpoint as if nothing happened (and so we don't call
2773 static ULONGEST current_stop_id;
2780 return current_stop_id;
2783 /* Called when we report a user visible stop. */
2791 /* Clear out all variables saying what to do when inferior is continued.
2792 First do this, then set the ones you want, then call `proceed'. */
2795 clear_proceed_status_thread (struct thread_info *tp)
2798 fprintf_unfiltered (gdb_stdlog,
2799 "infrun: clear_proceed_status_thread (%s)\n",
2800 target_pid_to_str (tp->ptid));
2802 /* If we're starting a new sequence, then the previous finished
2803 single-step is no longer relevant. */
2804 if (tp->suspend.waitstatus_pending_p)
2806 if (tp->suspend.stop_reason == TARGET_STOPPED_BY_SINGLE_STEP)
2809 fprintf_unfiltered (gdb_stdlog,
2810 "infrun: clear_proceed_status: pending "
2811 "event of %s was a finished step. "
2813 target_pid_to_str (tp->ptid));
2815 tp->suspend.waitstatus_pending_p = 0;
2816 tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON;
2818 else if (debug_infrun)
2821 = target_waitstatus_to_string (&tp->suspend.waitstatus);
2823 fprintf_unfiltered (gdb_stdlog,
2824 "infrun: clear_proceed_status_thread: thread %s "
2825 "has pending wait status %s "
2826 "(currently_stepping=%d).\n",
2827 target_pid_to_str (tp->ptid), statstr.c_str (),
2828 currently_stepping (tp));
2832 /* If this signal should not be seen by program, give it zero.
2833 Used for debugging signals. */
2834 if (!signal_pass_state (tp->suspend.stop_signal))
2835 tp->suspend.stop_signal = GDB_SIGNAL_0;
2837 thread_fsm_delete (tp->thread_fsm);
2838 tp->thread_fsm = NULL;
2840 tp->control.trap_expected = 0;
2841 tp->control.step_range_start = 0;
2842 tp->control.step_range_end = 0;
2843 tp->control.may_range_step = 0;
2844 tp->control.step_frame_id = null_frame_id;
2845 tp->control.step_stack_frame_id = null_frame_id;
2846 tp->control.step_over_calls = STEP_OVER_UNDEBUGGABLE;
2847 tp->control.step_start_function = NULL;
2848 tp->stop_requested = 0;
2850 tp->control.stop_step = 0;
2852 tp->control.proceed_to_finish = 0;
2854 tp->control.stepping_command = 0;
2856 /* Discard any remaining commands or status from previous stop. */
2857 bpstat_clear (&tp->control.stop_bpstat);
2861 clear_proceed_status (int step)
2863 /* With scheduler-locking replay, stop replaying other threads if we're
2864 not replaying the user-visible resume ptid.
2866 This is a convenience feature to not require the user to explicitly
2867 stop replaying the other threads. We're assuming that the user's
2868 intent is to resume tracing the recorded process. */
2869 if (!non_stop && scheduler_mode == schedlock_replay
2870 && target_record_is_replaying (minus_one_ptid)
2871 && !target_record_will_replay (user_visible_resume_ptid (step),
2872 execution_direction))
2873 target_record_stop_replaying ();
2877 struct thread_info *tp;
2880 resume_ptid = user_visible_resume_ptid (step);
2882 /* In all-stop mode, delete the per-thread status of all threads
2883 we're about to resume, implicitly and explicitly. */
2884 ALL_NON_EXITED_THREADS (tp)
2886 if (!ptid_match (tp->ptid, resume_ptid))
2888 clear_proceed_status_thread (tp);
2892 if (!ptid_equal (inferior_ptid, null_ptid))
2894 struct inferior *inferior;
2898 /* If in non-stop mode, only delete the per-thread status of
2899 the current thread. */
2900 clear_proceed_status_thread (inferior_thread ());
2903 inferior = current_inferior ();
2904 inferior->control.stop_soon = NO_STOP_QUIETLY;
2907 observer_notify_about_to_proceed ();
2910 /* Returns true if TP is still stopped at a breakpoint that needs
2911 stepping-over in order to make progress. If the breakpoint is gone
2912 meanwhile, we can skip the whole step-over dance. */
2915 thread_still_needs_step_over_bp (struct thread_info *tp)
2917 if (tp->stepping_over_breakpoint)
2919 struct regcache *regcache = get_thread_regcache (tp->ptid);
2921 if (breakpoint_here_p (get_regcache_aspace (regcache),
2922 regcache_read_pc (regcache))
2923 == ordinary_breakpoint_here)
2926 tp->stepping_over_breakpoint = 0;
2932 /* Check whether thread TP still needs to start a step-over in order
2933 to make progress when resumed. Returns an bitwise or of enum
2934 step_over_what bits, indicating what needs to be stepped over. */
2936 static step_over_what
2937 thread_still_needs_step_over (struct thread_info *tp)
2939 step_over_what what = 0;
2941 if (thread_still_needs_step_over_bp (tp))
2942 what |= STEP_OVER_BREAKPOINT;
2944 if (tp->stepping_over_watchpoint
2945 && !target_have_steppable_watchpoint)
2946 what |= STEP_OVER_WATCHPOINT;
2951 /* Returns true if scheduler locking applies. STEP indicates whether
2952 we're about to do a step/next-like command to a thread. */
2955 schedlock_applies (struct thread_info *tp)
2957 return (scheduler_mode == schedlock_on
2958 || (scheduler_mode == schedlock_step
2959 && tp->control.stepping_command)
2960 || (scheduler_mode == schedlock_replay
2961 && target_record_will_replay (minus_one_ptid,
2962 execution_direction)));
2965 /* Basic routine for continuing the program in various fashions.
2967 ADDR is the address to resume at, or -1 for resume where stopped.
2968 SIGGNAL is the signal to give it, or 0 for none,
2969 or -1 for act according to how it stopped.
2970 STEP is nonzero if should trap after one instruction.
2971 -1 means return after that and print nothing.
2972 You should probably set various step_... variables
2973 before calling here, if you are stepping.
2975 You should call clear_proceed_status before calling proceed. */
2978 proceed (CORE_ADDR addr, enum gdb_signal siggnal)
2980 struct regcache *regcache;
2981 struct gdbarch *gdbarch;
2982 struct thread_info *tp;
2984 struct address_space *aspace;
2986 struct execution_control_state ecss;
2987 struct execution_control_state *ecs = &ecss;
2988 struct cleanup *old_chain;
2991 /* If we're stopped at a fork/vfork, follow the branch set by the
2992 "set follow-fork-mode" command; otherwise, we'll just proceed
2993 resuming the current thread. */
2994 if (!follow_fork ())
2996 /* The target for some reason decided not to resume. */
2998 if (target_can_async_p ())
2999 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
3003 /* We'll update this if & when we switch to a new thread. */
3004 previous_inferior_ptid = inferior_ptid;
3006 regcache = get_current_regcache ();
3007 gdbarch = get_regcache_arch (regcache);
3008 aspace = get_regcache_aspace (regcache);
3009 pc = regcache_read_pc (regcache);
3010 tp = inferior_thread ();
3012 /* Fill in with reasonable starting values. */
3013 init_thread_stepping_state (tp);
3015 gdb_assert (!thread_is_in_step_over_chain (tp));
3017 if (addr == (CORE_ADDR) -1)
3020 && breakpoint_here_p (aspace, pc) == ordinary_breakpoint_here
3021 && execution_direction != EXEC_REVERSE)
3022 /* There is a breakpoint at the address we will resume at,
3023 step one instruction before inserting breakpoints so that
3024 we do not stop right away (and report a second hit at this
3027 Note, we don't do this in reverse, because we won't
3028 actually be executing the breakpoint insn anyway.
3029 We'll be (un-)executing the previous instruction. */
3030 tp->stepping_over_breakpoint = 1;
3031 else if (gdbarch_single_step_through_delay_p (gdbarch)
3032 && gdbarch_single_step_through_delay (gdbarch,
3033 get_current_frame ()))
3034 /* We stepped onto an instruction that needs to be stepped
3035 again before re-inserting the breakpoint, do so. */
3036 tp->stepping_over_breakpoint = 1;
3040 regcache_write_pc (regcache, addr);
3043 if (siggnal != GDB_SIGNAL_DEFAULT)
3044 tp->suspend.stop_signal = siggnal;
3046 resume_ptid = user_visible_resume_ptid (tp->control.stepping_command);
3048 /* If an exception is thrown from this point on, make sure to
3049 propagate GDB's knowledge of the executing state to the
3050 frontend/user running state. */
3051 old_chain = make_cleanup (finish_thread_state_cleanup, &resume_ptid);
3053 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3054 threads (e.g., we might need to set threads stepping over
3055 breakpoints first), from the user/frontend's point of view, all
3056 threads in RESUME_PTID are now running. Unless we're calling an
3057 inferior function, as in that case we pretend the inferior
3058 doesn't run at all. */
3059 if (!tp->control.in_infcall)
3060 set_running (resume_ptid, 1);
3063 fprintf_unfiltered (gdb_stdlog,
3064 "infrun: proceed (addr=%s, signal=%s)\n",
3065 paddress (gdbarch, addr),
3066 gdb_signal_to_symbol_string (siggnal));
3068 annotate_starting ();
3070 /* Make sure that output from GDB appears before output from the
3072 gdb_flush (gdb_stdout);
3074 /* In a multi-threaded task we may select another thread and
3075 then continue or step.
3077 But if a thread that we're resuming had stopped at a breakpoint,
3078 it will immediately cause another breakpoint stop without any
3079 execution (i.e. it will report a breakpoint hit incorrectly). So
3080 we must step over it first.
3082 Look for threads other than the current (TP) that reported a
3083 breakpoint hit and haven't been resumed yet since. */
3085 /* If scheduler locking applies, we can avoid iterating over all
3087 if (!non_stop && !schedlock_applies (tp))
3089 struct thread_info *current = tp;
3091 ALL_NON_EXITED_THREADS (tp)
3093 /* Ignore the current thread here. It's handled
3098 /* Ignore threads of processes we're not resuming. */
3099 if (!ptid_match (tp->ptid, resume_ptid))
3102 if (!thread_still_needs_step_over (tp))
3105 gdb_assert (!thread_is_in_step_over_chain (tp));
3108 fprintf_unfiltered (gdb_stdlog,
3109 "infrun: need to step-over [%s] first\n",
3110 target_pid_to_str (tp->ptid));
3112 thread_step_over_chain_enqueue (tp);
3118 /* Enqueue the current thread last, so that we move all other
3119 threads over their breakpoints first. */
3120 if (tp->stepping_over_breakpoint)
3121 thread_step_over_chain_enqueue (tp);
3123 /* If the thread isn't started, we'll still need to set its prev_pc,
3124 so that switch_back_to_stepped_thread knows the thread hasn't
3125 advanced. Must do this before resuming any thread, as in
3126 all-stop/remote, once we resume we can't send any other packet
3127 until the target stops again. */
3128 tp->prev_pc = regcache_read_pc (regcache);
3131 scoped_restore save_defer_tc = make_scoped_defer_target_commit_resume ();
3133 started = start_step_over ();
3135 if (step_over_info_valid_p ())
3137 /* Either this thread started a new in-line step over, or some
3138 other thread was already doing one. In either case, don't
3139 resume anything else until the step-over is finished. */
3141 else if (started && !target_is_non_stop_p ())
3143 /* A new displaced stepping sequence was started. In all-stop,
3144 we can't talk to the target anymore until it next stops. */
3146 else if (!non_stop && target_is_non_stop_p ())
3148 /* In all-stop, but the target is always in non-stop mode.
3149 Start all other threads that are implicitly resumed too. */
3150 ALL_NON_EXITED_THREADS (tp)
3152 /* Ignore threads of processes we're not resuming. */
3153 if (!ptid_match (tp->ptid, resume_ptid))
3159 fprintf_unfiltered (gdb_stdlog,
3160 "infrun: proceed: [%s] resumed\n",
3161 target_pid_to_str (tp->ptid));
3162 gdb_assert (tp->executing || tp->suspend.waitstatus_pending_p);
3166 if (thread_is_in_step_over_chain (tp))
3169 fprintf_unfiltered (gdb_stdlog,
3170 "infrun: proceed: [%s] needs step-over\n",
3171 target_pid_to_str (tp->ptid));
3176 fprintf_unfiltered (gdb_stdlog,
3177 "infrun: proceed: resuming %s\n",
3178 target_pid_to_str (tp->ptid));
3180 reset_ecs (ecs, tp);
3181 switch_to_thread (tp->ptid);
3182 keep_going_pass_signal (ecs);
3183 if (!ecs->wait_some_more)
3184 error (_("Command aborted."));
3187 else if (!tp->resumed && !thread_is_in_step_over_chain (tp))
3189 /* The thread wasn't started, and isn't queued, run it now. */
3190 reset_ecs (ecs, tp);
3191 switch_to_thread (tp->ptid);
3192 keep_going_pass_signal (ecs);
3193 if (!ecs->wait_some_more)
3194 error (_("Command aborted."));
3198 target_commit_resume ();
3200 discard_cleanups (old_chain);
3202 /* Tell the event loop to wait for it to stop. If the target
3203 supports asynchronous execution, it'll do this from within
3205 if (!target_can_async_p ())
3206 mark_async_event_handler (infrun_async_inferior_event_token);
3210 /* Start remote-debugging of a machine over a serial link. */
3213 start_remote (int from_tty)
3215 struct inferior *inferior;
3217 inferior = current_inferior ();
3218 inferior->control.stop_soon = STOP_QUIETLY_REMOTE;
3220 /* Always go on waiting for the target, regardless of the mode. */
3221 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3222 indicate to wait_for_inferior that a target should timeout if
3223 nothing is returned (instead of just blocking). Because of this,
3224 targets expecting an immediate response need to, internally, set
3225 things up so that the target_wait() is forced to eventually
3227 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3228 differentiate to its caller what the state of the target is after
3229 the initial open has been performed. Here we're assuming that
3230 the target has stopped. It should be possible to eventually have
3231 target_open() return to the caller an indication that the target
3232 is currently running and GDB state should be set to the same as
3233 for an async run. */
3234 wait_for_inferior ();
3236 /* Now that the inferior has stopped, do any bookkeeping like
3237 loading shared libraries. We want to do this before normal_stop,
3238 so that the displayed frame is up to date. */
3239 post_create_inferior (¤t_target, from_tty);
3244 /* Initialize static vars when a new inferior begins. */
3247 init_wait_for_inferior (void)
3249 /* These are meaningless until the first time through wait_for_inferior. */
3251 breakpoint_init_inferior (inf_starting);
3253 clear_proceed_status (0);
3255 target_last_wait_ptid = minus_one_ptid;
3257 previous_inferior_ptid = inferior_ptid;
3259 /* Discard any skipped inlined frames. */
3260 clear_inline_frame_state (minus_one_ptid);
3265 static void handle_inferior_event (struct execution_control_state *ecs);
3267 static void handle_step_into_function (struct gdbarch *gdbarch,
3268 struct execution_control_state *ecs);
3269 static void handle_step_into_function_backward (struct gdbarch *gdbarch,
3270 struct execution_control_state *ecs);
3271 static void handle_signal_stop (struct execution_control_state *ecs);
3272 static void check_exception_resume (struct execution_control_state *,
3273 struct frame_info *);
3275 static void end_stepping_range (struct execution_control_state *ecs);
3276 static void stop_waiting (struct execution_control_state *ecs);
3277 static void keep_going (struct execution_control_state *ecs);
3278 static void process_event_stop_test (struct execution_control_state *ecs);
3279 static int switch_back_to_stepped_thread (struct execution_control_state *ecs);
3281 /* This function is attached as a "thread_stop_requested" observer.
3282 Cleanup local state that assumed the PTID was to be resumed, and
3283 report the stop to the frontend. */
3286 infrun_thread_stop_requested (ptid_t ptid)
3288 struct thread_info *tp;
3290 /* PTID was requested to stop. If the thread was already stopped,
3291 but the user/frontend doesn't know about that yet (e.g., the
3292 thread had been temporarily paused for some step-over), set up
3293 for reporting the stop now. */
3294 ALL_NON_EXITED_THREADS (tp)
3295 if (ptid_match (tp->ptid, ptid))
3297 if (tp->state != THREAD_RUNNING)
3302 /* Remove matching threads from the step-over queue, so
3303 start_step_over doesn't try to resume them
3305 if (thread_is_in_step_over_chain (tp))
3306 thread_step_over_chain_remove (tp);
3308 /* If the thread is stopped, but the user/frontend doesn't
3309 know about that yet, queue a pending event, as if the
3310 thread had just stopped now. Unless the thread already had
3312 if (!tp->suspend.waitstatus_pending_p)
3314 tp->suspend.waitstatus_pending_p = 1;
3315 tp->suspend.waitstatus.kind = TARGET_WAITKIND_STOPPED;
3316 tp->suspend.waitstatus.value.sig = GDB_SIGNAL_0;
3319 /* Clear the inline-frame state, since we're re-processing the
3321 clear_inline_frame_state (tp->ptid);
3323 /* If this thread was paused because some other thread was
3324 doing an inline-step over, let that finish first. Once
3325 that happens, we'll restart all threads and consume pending
3326 stop events then. */
3327 if (step_over_info_valid_p ())
3330 /* Otherwise we can process the (new) pending event now. Set
3331 it so this pending event is considered by
3338 infrun_thread_thread_exit (struct thread_info *tp, int silent)
3340 if (ptid_equal (target_last_wait_ptid, tp->ptid))
3341 nullify_last_target_wait_ptid ();
3344 /* Delete the step resume, single-step and longjmp/exception resume
3345 breakpoints of TP. */
3348 delete_thread_infrun_breakpoints (struct thread_info *tp)
3350 delete_step_resume_breakpoint (tp);
3351 delete_exception_resume_breakpoint (tp);
3352 delete_single_step_breakpoints (tp);
3355 /* If the target still has execution, call FUNC for each thread that
3356 just stopped. In all-stop, that's all the non-exited threads; in
3357 non-stop, that's the current thread, only. */
3359 typedef void (*for_each_just_stopped_thread_callback_func)
3360 (struct thread_info *tp);
3363 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func)
3365 if (!target_has_execution || ptid_equal (inferior_ptid, null_ptid))
3368 if (target_is_non_stop_p ())
3370 /* If in non-stop mode, only the current thread stopped. */
3371 func (inferior_thread ());
3375 struct thread_info *tp;
3377 /* In all-stop mode, all threads have stopped. */
3378 ALL_NON_EXITED_THREADS (tp)
3385 /* Delete the step resume and longjmp/exception resume breakpoints of
3386 the threads that just stopped. */
3389 delete_just_stopped_threads_infrun_breakpoints (void)
3391 for_each_just_stopped_thread (delete_thread_infrun_breakpoints);
3394 /* Delete the single-step breakpoints of the threads that just
3398 delete_just_stopped_threads_single_step_breakpoints (void)
3400 for_each_just_stopped_thread (delete_single_step_breakpoints);
3403 /* A cleanup wrapper. */
3406 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg)
3408 delete_just_stopped_threads_infrun_breakpoints ();
3414 print_target_wait_results (ptid_t waiton_ptid, ptid_t result_ptid,
3415 const struct target_waitstatus *ws)
3417 std::string status_string = target_waitstatus_to_string (ws);
3420 /* The text is split over several lines because it was getting too long.
3421 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3422 output as a unit; we want only one timestamp printed if debug_timestamp
3425 stb.printf ("infrun: target_wait (%d.%ld.%ld",
3426 ptid_get_pid (waiton_ptid),
3427 ptid_get_lwp (waiton_ptid),
3428 ptid_get_tid (waiton_ptid));
3429 if (ptid_get_pid (waiton_ptid) != -1)
3430 stb.printf (" [%s]", target_pid_to_str (waiton_ptid));
3431 stb.printf (", status) =\n");
3432 stb.printf ("infrun: %d.%ld.%ld [%s],\n",
3433 ptid_get_pid (result_ptid),
3434 ptid_get_lwp (result_ptid),
3435 ptid_get_tid (result_ptid),
3436 target_pid_to_str (result_ptid));
3437 stb.printf ("infrun: %s\n", status_string.c_str ());
3439 /* This uses %s in part to handle %'s in the text, but also to avoid
3440 a gcc error: the format attribute requires a string literal. */
3441 fprintf_unfiltered (gdb_stdlog, "%s", stb.c_str ());
3444 /* Select a thread at random, out of those which are resumed and have
3447 static struct thread_info *
3448 random_pending_event_thread (ptid_t waiton_ptid)
3450 struct thread_info *event_tp;
3452 int random_selector;
3454 /* First see how many events we have. Count only resumed threads
3455 that have an event pending. */
3456 ALL_NON_EXITED_THREADS (event_tp)
3457 if (ptid_match (event_tp->ptid, waiton_ptid)
3458 && event_tp->resumed
3459 && event_tp->suspend.waitstatus_pending_p)
3462 if (num_events == 0)
3465 /* Now randomly pick a thread out of those that have had events. */
3466 random_selector = (int)
3467 ((num_events * (double) rand ()) / (RAND_MAX + 1.0));
3469 if (debug_infrun && num_events > 1)
3470 fprintf_unfiltered (gdb_stdlog,
3471 "infrun: Found %d events, selecting #%d\n",
3472 num_events, random_selector);
3474 /* Select the Nth thread that has had an event. */
3475 ALL_NON_EXITED_THREADS (event_tp)
3476 if (ptid_match (event_tp->ptid, waiton_ptid)
3477 && event_tp->resumed
3478 && event_tp->suspend.waitstatus_pending_p)
3479 if (random_selector-- == 0)
3485 /* Wrapper for target_wait that first checks whether threads have
3486 pending statuses to report before actually asking the target for
3490 do_target_wait (ptid_t ptid, struct target_waitstatus *status, int options)
3493 struct thread_info *tp;
3495 /* First check if there is a resumed thread with a wait status
3497 if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid))
3499 tp = random_pending_event_thread (ptid);
3504 fprintf_unfiltered (gdb_stdlog,
3505 "infrun: Waiting for specific thread %s.\n",
3506 target_pid_to_str (ptid));
3508 /* We have a specific thread to check. */
3509 tp = find_thread_ptid (ptid);
3510 gdb_assert (tp != NULL);
3511 if (!tp->suspend.waitstatus_pending_p)
3516 && (tp->suspend.stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3517 || tp->suspend.stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT))
3519 struct regcache *regcache = get_thread_regcache (tp->ptid);
3520 struct gdbarch *gdbarch = get_regcache_arch (regcache);
3524 pc = regcache_read_pc (regcache);
3526 if (pc != tp->suspend.stop_pc)
3529 fprintf_unfiltered (gdb_stdlog,
3530 "infrun: PC of %s changed. was=%s, now=%s\n",
3531 target_pid_to_str (tp->ptid),
3532 paddress (gdbarch, tp->prev_pc),
3533 paddress (gdbarch, pc));
3536 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc))
3539 fprintf_unfiltered (gdb_stdlog,
3540 "infrun: previous breakpoint of %s, at %s gone\n",
3541 target_pid_to_str (tp->ptid),
3542 paddress (gdbarch, pc));
3550 fprintf_unfiltered (gdb_stdlog,
3551 "infrun: pending event of %s cancelled.\n",
3552 target_pid_to_str (tp->ptid));
3554 tp->suspend.waitstatus.kind = TARGET_WAITKIND_SPURIOUS;
3555 tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON;
3564 = target_waitstatus_to_string (&tp->suspend.waitstatus);
3566 fprintf_unfiltered (gdb_stdlog,
3567 "infrun: Using pending wait status %s for %s.\n",
3569 target_pid_to_str (tp->ptid));
3572 /* Now that we've selected our final event LWP, un-adjust its PC
3573 if it was a software breakpoint (and the target doesn't
3574 always adjust the PC itself). */
3575 if (tp->suspend.stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3576 && !target_supports_stopped_by_sw_breakpoint ())
3578 struct regcache *regcache;
3579 struct gdbarch *gdbarch;
3582 regcache = get_thread_regcache (tp->ptid);
3583 gdbarch = get_regcache_arch (regcache);
3585 decr_pc = gdbarch_decr_pc_after_break (gdbarch);
3590 pc = regcache_read_pc (regcache);
3591 regcache_write_pc (regcache, pc + decr_pc);
3595 tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON;
3596 *status = tp->suspend.waitstatus;
3597 tp->suspend.waitstatus_pending_p = 0;
3599 /* Wake up the event loop again, until all pending events are
3601 if (target_is_async_p ())
3602 mark_async_event_handler (infrun_async_inferior_event_token);
3606 /* But if we don't find one, we'll have to wait. */
3608 if (deprecated_target_wait_hook)
3609 event_ptid = deprecated_target_wait_hook (ptid, status, options);
3611 event_ptid = target_wait (ptid, status, options);
3616 /* Prepare and stabilize the inferior for detaching it. E.g.,
3617 detaching while a thread is displaced stepping is a recipe for
3618 crashing it, as nothing would readjust the PC out of the scratch
3622 prepare_for_detach (void)
3624 struct inferior *inf = current_inferior ();
3625 ptid_t pid_ptid = pid_to_ptid (inf->pid);
3626 struct displaced_step_inferior_state *displaced;
3628 displaced = get_displaced_stepping_state (inf->pid);
3630 /* Is any thread of this process displaced stepping? If not,
3631 there's nothing else to do. */
3632 if (displaced == NULL || ptid_equal (displaced->step_ptid, null_ptid))
3636 fprintf_unfiltered (gdb_stdlog,
3637 "displaced-stepping in-process while detaching");
3639 scoped_restore restore_detaching = make_scoped_restore (&inf->detaching, true);
3641 while (!ptid_equal (displaced->step_ptid, null_ptid))
3643 struct cleanup *old_chain_2;
3644 struct execution_control_state ecss;
3645 struct execution_control_state *ecs;
3648 memset (ecs, 0, sizeof (*ecs));
3650 overlay_cache_invalid = 1;
3651 /* Flush target cache before starting to handle each event.
3652 Target was running and cache could be stale. This is just a
3653 heuristic. Running threads may modify target memory, but we
3654 don't get any event. */
3655 target_dcache_invalidate ();
3657 ecs->ptid = do_target_wait (pid_ptid, &ecs->ws, 0);
3660 print_target_wait_results (pid_ptid, ecs->ptid, &ecs->ws);
3662 /* If an error happens while handling the event, propagate GDB's
3663 knowledge of the executing state to the frontend/user running
3665 old_chain_2 = make_cleanup (finish_thread_state_cleanup,
3668 /* Now figure out what to do with the result of the result. */
3669 handle_inferior_event (ecs);
3671 /* No error, don't finish the state yet. */
3672 discard_cleanups (old_chain_2);
3674 /* Breakpoints and watchpoints are not installed on the target
3675 at this point, and signals are passed directly to the
3676 inferior, so this must mean the process is gone. */
3677 if (!ecs->wait_some_more)
3679 restore_detaching.release ();
3680 error (_("Program exited while detaching"));
3684 restore_detaching.release ();
3687 /* Wait for control to return from inferior to debugger.
3689 If inferior gets a signal, we may decide to start it up again
3690 instead of returning. That is why there is a loop in this function.
3691 When this function actually returns it means the inferior
3692 should be left stopped and GDB should read more commands. */
3695 wait_for_inferior (void)
3697 struct cleanup *old_cleanups;
3698 struct cleanup *thread_state_chain;
3702 (gdb_stdlog, "infrun: wait_for_inferior ()\n");
3705 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup,
3708 /* If an error happens while handling the event, propagate GDB's
3709 knowledge of the executing state to the frontend/user running
3711 thread_state_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
3715 struct execution_control_state ecss;
3716 struct execution_control_state *ecs = &ecss;
3717 ptid_t waiton_ptid = minus_one_ptid;
3719 memset (ecs, 0, sizeof (*ecs));
3721 overlay_cache_invalid = 1;
3723 /* Flush target cache before starting to handle each event.
3724 Target was running and cache could be stale. This is just a
3725 heuristic. Running threads may modify target memory, but we
3726 don't get any event. */
3727 target_dcache_invalidate ();
3729 ecs->ptid = do_target_wait (waiton_ptid, &ecs->ws, 0);
3732 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
3734 /* Now figure out what to do with the result of the result. */
3735 handle_inferior_event (ecs);
3737 if (!ecs->wait_some_more)
3741 /* No error, don't finish the state yet. */
3742 discard_cleanups (thread_state_chain);
3744 do_cleanups (old_cleanups);
3747 /* Cleanup that reinstalls the readline callback handler, if the
3748 target is running in the background. If while handling the target
3749 event something triggered a secondary prompt, like e.g., a
3750 pagination prompt, we'll have removed the callback handler (see
3751 gdb_readline_wrapper_line). Need to do this as we go back to the
3752 event loop, ready to process further input. Note this has no
3753 effect if the handler hasn't actually been removed, because calling
3754 rl_callback_handler_install resets the line buffer, thus losing
3758 reinstall_readline_callback_handler_cleanup (void *arg)
3760 struct ui *ui = current_ui;
3764 /* We're not going back to the top level event loop yet. Don't
3765 install the readline callback, as it'd prep the terminal,
3766 readline-style (raw, noecho) (e.g., --batch). We'll install
3767 it the next time the prompt is displayed, when we're ready
3772 if (ui->command_editing && ui->prompt_state != PROMPT_BLOCKED)
3773 gdb_rl_callback_handler_reinstall ();
3776 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3777 that's just the event thread. In all-stop, that's all threads. */
3780 clean_up_just_stopped_threads_fsms (struct execution_control_state *ecs)
3782 struct thread_info *thr = ecs->event_thread;
3784 if (thr != NULL && thr->thread_fsm != NULL)
3785 thread_fsm_clean_up (thr->thread_fsm, thr);
3789 ALL_NON_EXITED_THREADS (thr)
3791 if (thr->thread_fsm == NULL)
3793 if (thr == ecs->event_thread)
3796 switch_to_thread (thr->ptid);
3797 thread_fsm_clean_up (thr->thread_fsm, thr);
3800 if (ecs->event_thread != NULL)
3801 switch_to_thread (ecs->event_thread->ptid);
3805 /* Helper for all_uis_check_sync_execution_done that works on the
3809 check_curr_ui_sync_execution_done (void)
3811 struct ui *ui = current_ui;
3813 if (ui->prompt_state == PROMPT_NEEDED
3815 && !gdb_in_secondary_prompt_p (ui))
3817 target_terminal::ours ();
3818 observer_notify_sync_execution_done ();
3819 ui_register_input_event_handler (ui);
3826 all_uis_check_sync_execution_done (void)
3828 SWITCH_THRU_ALL_UIS ()
3830 check_curr_ui_sync_execution_done ();
3837 all_uis_on_sync_execution_starting (void)
3839 SWITCH_THRU_ALL_UIS ()
3841 if (current_ui->prompt_state == PROMPT_NEEDED)
3842 async_disable_stdin ();
3846 /* Asynchronous version of wait_for_inferior. It is called by the
3847 event loop whenever a change of state is detected on the file
3848 descriptor corresponding to the target. It can be called more than
3849 once to complete a single execution command. In such cases we need
3850 to keep the state in a global variable ECSS. If it is the last time
3851 that this function is called for a single execution command, then
3852 report to the user that the inferior has stopped, and do the
3853 necessary cleanups. */
3856 fetch_inferior_event (void *client_data)
3858 struct execution_control_state ecss;
3859 struct execution_control_state *ecs = &ecss;
3860 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
3861 struct cleanup *ts_old_chain;
3863 ptid_t waiton_ptid = minus_one_ptid;
3865 memset (ecs, 0, sizeof (*ecs));
3867 /* Events are always processed with the main UI as current UI. This
3868 way, warnings, debug output, etc. are always consistently sent to
3869 the main console. */
3870 scoped_restore save_ui = make_scoped_restore (¤t_ui, main_ui);
3872 /* End up with readline processing input, if necessary. */
3873 make_cleanup (reinstall_readline_callback_handler_cleanup, NULL);
3875 /* We're handling a live event, so make sure we're doing live
3876 debugging. If we're looking at traceframes while the target is
3877 running, we're going to need to get back to that mode after
3878 handling the event. */
3881 make_cleanup_restore_current_traceframe ();
3882 set_current_traceframe (-1);
3885 gdb::optional<scoped_restore_current_thread> maybe_restore_thread;
3888 /* In non-stop mode, the user/frontend should not notice a thread
3889 switch due to internal events. Make sure we reverse to the
3890 user selected thread and frame after handling the event and
3891 running any breakpoint commands. */
3892 maybe_restore_thread.emplace ();
3894 overlay_cache_invalid = 1;
3895 /* Flush target cache before starting to handle each event. Target
3896 was running and cache could be stale. This is just a heuristic.
3897 Running threads may modify target memory, but we don't get any
3899 target_dcache_invalidate ();
3901 scoped_restore save_exec_dir
3902 = make_scoped_restore (&execution_direction, target_execution_direction ());
3904 ecs->ptid = do_target_wait (waiton_ptid, &ecs->ws,
3905 target_can_async_p () ? TARGET_WNOHANG : 0);
3908 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
3910 /* If an error happens while handling the event, propagate GDB's
3911 knowledge of the executing state to the frontend/user running
3913 if (!target_is_non_stop_p ())
3914 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
3916 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &ecs->ptid);
3918 /* Get executed before make_cleanup_restore_current_thread above to apply
3919 still for the thread which has thrown the exception. */
3920 make_bpstat_clear_actions_cleanup ();
3922 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup, NULL);
3924 /* Now figure out what to do with the result of the result. */
3925 handle_inferior_event (ecs);
3927 if (!ecs->wait_some_more)
3929 struct inferior *inf = find_inferior_ptid (ecs->ptid);
3930 int should_stop = 1;
3931 struct thread_info *thr = ecs->event_thread;
3932 int should_notify_stop = 1;
3934 delete_just_stopped_threads_infrun_breakpoints ();
3938 struct thread_fsm *thread_fsm = thr->thread_fsm;
3940 if (thread_fsm != NULL)
3941 should_stop = thread_fsm_should_stop (thread_fsm, thr);
3950 clean_up_just_stopped_threads_fsms (ecs);
3952 if (thr != NULL && thr->thread_fsm != NULL)
3955 = thread_fsm_should_notify_stop (thr->thread_fsm);
3958 if (should_notify_stop)
3962 /* We may not find an inferior if this was a process exit. */
3963 if (inf == NULL || inf->control.stop_soon == NO_STOP_QUIETLY)
3964 proceeded = normal_stop ();
3968 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
3975 /* No error, don't finish the thread states yet. */
3976 discard_cleanups (ts_old_chain);
3978 /* Revert thread and frame. */
3979 do_cleanups (old_chain);
3981 /* If a UI was in sync execution mode, and now isn't, restore its
3982 prompt (a synchronous execution command has finished, and we're
3983 ready for input). */
3984 all_uis_check_sync_execution_done ();
3987 && exec_done_display_p
3988 && (ptid_equal (inferior_ptid, null_ptid)
3989 || !is_running (inferior_ptid)))
3990 printf_unfiltered (_("completed.\n"));
3993 /* Record the frame and location we're currently stepping through. */
3995 set_step_info (struct frame_info *frame, struct symtab_and_line sal)
3997 struct thread_info *tp = inferior_thread ();
3999 tp->control.step_frame_id = get_frame_id (frame);
4000 tp->control.step_stack_frame_id = get_stack_frame_id (frame);
4002 tp->current_symtab = sal.symtab;
4003 tp->current_line = sal.line;
4006 /* Clear context switchable stepping state. */
4009 init_thread_stepping_state (struct thread_info *tss)
4011 tss->stepped_breakpoint = 0;
4012 tss->stepping_over_breakpoint = 0;
4013 tss->stepping_over_watchpoint = 0;
4014 tss->step_after_step_resume_breakpoint = 0;
4017 /* Set the cached copy of the last ptid/waitstatus. */
4020 set_last_target_status (ptid_t ptid, struct target_waitstatus status)
4022 target_last_wait_ptid = ptid;
4023 target_last_waitstatus = status;
4026 /* Return the cached copy of the last pid/waitstatus returned by
4027 target_wait()/deprecated_target_wait_hook(). The data is actually
4028 cached by handle_inferior_event(), which gets called immediately
4029 after target_wait()/deprecated_target_wait_hook(). */
4032 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
4034 *ptidp = target_last_wait_ptid;
4035 *status = target_last_waitstatus;
4039 nullify_last_target_wait_ptid (void)
4041 target_last_wait_ptid = minus_one_ptid;
4044 /* Switch thread contexts. */
4047 context_switch (ptid_t ptid)
4049 if (debug_infrun && !ptid_equal (ptid, inferior_ptid))
4051 fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ",
4052 target_pid_to_str (inferior_ptid));
4053 fprintf_unfiltered (gdb_stdlog, "to %s\n",
4054 target_pid_to_str (ptid));
4057 switch_to_thread (ptid);
4060 /* If the target can't tell whether we've hit breakpoints
4061 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4062 check whether that could have been caused by a breakpoint. If so,
4063 adjust the PC, per gdbarch_decr_pc_after_break. */
4066 adjust_pc_after_break (struct thread_info *thread,
4067 struct target_waitstatus *ws)
4069 struct regcache *regcache;
4070 struct gdbarch *gdbarch;
4071 struct address_space *aspace;
4072 CORE_ADDR breakpoint_pc, decr_pc;
4074 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4075 we aren't, just return.
4077 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4078 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4079 implemented by software breakpoints should be handled through the normal
4082 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4083 different signals (SIGILL or SIGEMT for instance), but it is less
4084 clear where the PC is pointing afterwards. It may not match
4085 gdbarch_decr_pc_after_break. I don't know any specific target that
4086 generates these signals at breakpoints (the code has been in GDB since at
4087 least 1992) so I can not guess how to handle them here.
4089 In earlier versions of GDB, a target with
4090 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4091 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4092 target with both of these set in GDB history, and it seems unlikely to be
4093 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4095 if (ws->kind != TARGET_WAITKIND_STOPPED)
4098 if (ws->value.sig != GDB_SIGNAL_TRAP)
4101 /* In reverse execution, when a breakpoint is hit, the instruction
4102 under it has already been de-executed. The reported PC always
4103 points at the breakpoint address, so adjusting it further would
4104 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4107 B1 0x08000000 : INSN1
4108 B2 0x08000001 : INSN2
4110 PC -> 0x08000003 : INSN4
4112 Say you're stopped at 0x08000003 as above. Reverse continuing
4113 from that point should hit B2 as below. Reading the PC when the
4114 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4115 been de-executed already.
4117 B1 0x08000000 : INSN1
4118 B2 PC -> 0x08000001 : INSN2
4122 We can't apply the same logic as for forward execution, because
4123 we would wrongly adjust the PC to 0x08000000, since there's a
4124 breakpoint at PC - 1. We'd then report a hit on B1, although
4125 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4127 if (execution_direction == EXEC_REVERSE)
4130 /* If the target can tell whether the thread hit a SW breakpoint,
4131 trust it. Targets that can tell also adjust the PC
4133 if (target_supports_stopped_by_sw_breakpoint ())
4136 /* Note that relying on whether a breakpoint is planted in memory to
4137 determine this can fail. E.g,. the breakpoint could have been
4138 removed since. Or the thread could have been told to step an
4139 instruction the size of a breakpoint instruction, and only
4140 _after_ was a breakpoint inserted at its address. */
4142 /* If this target does not decrement the PC after breakpoints, then
4143 we have nothing to do. */
4144 regcache = get_thread_regcache (thread->ptid);
4145 gdbarch = get_regcache_arch (regcache);
4147 decr_pc = gdbarch_decr_pc_after_break (gdbarch);
4151 aspace = get_regcache_aspace (regcache);
4153 /* Find the location where (if we've hit a breakpoint) the
4154 breakpoint would be. */
4155 breakpoint_pc = regcache_read_pc (regcache) - decr_pc;
4157 /* If the target can't tell whether a software breakpoint triggered,
4158 fallback to figuring it out based on breakpoints we think were
4159 inserted in the target, and on whether the thread was stepped or
4162 /* Check whether there actually is a software breakpoint inserted at
4165 If in non-stop mode, a race condition is possible where we've
4166 removed a breakpoint, but stop events for that breakpoint were
4167 already queued and arrive later. To suppress those spurious
4168 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4169 and retire them after a number of stop events are reported. Note
4170 this is an heuristic and can thus get confused. The real fix is
4171 to get the "stopped by SW BP and needs adjustment" info out of
4172 the target/kernel (and thus never reach here; see above). */
4173 if (software_breakpoint_inserted_here_p (aspace, breakpoint_pc)
4174 || (target_is_non_stop_p ()
4175 && moribund_breakpoint_here_p (aspace, breakpoint_pc)))
4177 gdb::optional<scoped_restore_tmpl<int>> restore_operation_disable;
4179 if (record_full_is_used ())
4180 restore_operation_disable.emplace
4181 (record_full_gdb_operation_disable_set ());
4183 /* When using hardware single-step, a SIGTRAP is reported for both
4184 a completed single-step and a software breakpoint. Need to
4185 differentiate between the two, as the latter needs adjusting
4186 but the former does not.
4188 The SIGTRAP can be due to a completed hardware single-step only if
4189 - we didn't insert software single-step breakpoints
4190 - this thread is currently being stepped
4192 If any of these events did not occur, we must have stopped due
4193 to hitting a software breakpoint, and have to back up to the
4196 As a special case, we could have hardware single-stepped a
4197 software breakpoint. In this case (prev_pc == breakpoint_pc),
4198 we also need to back up to the breakpoint address. */
4200 if (thread_has_single_step_breakpoints_set (thread)
4201 || !currently_stepping (thread)
4202 || (thread->stepped_breakpoint
4203 && thread->prev_pc == breakpoint_pc))
4204 regcache_write_pc (regcache, breakpoint_pc);
4209 stepped_in_from (struct frame_info *frame, struct frame_id step_frame_id)
4211 for (frame = get_prev_frame (frame);
4213 frame = get_prev_frame (frame))
4215 if (frame_id_eq (get_frame_id (frame), step_frame_id))
4217 if (get_frame_type (frame) != INLINE_FRAME)
4224 /* If the event thread has the stop requested flag set, pretend it
4225 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4229 handle_stop_requested (struct execution_control_state *ecs)
4231 if (ecs->event_thread->stop_requested)
4233 ecs->ws.kind = TARGET_WAITKIND_STOPPED;
4234 ecs->ws.value.sig = GDB_SIGNAL_0;
4235 handle_signal_stop (ecs);
4241 /* Auxiliary function that handles syscall entry/return events.
4242 It returns 1 if the inferior should keep going (and GDB
4243 should ignore the event), or 0 if the event deserves to be
4247 handle_syscall_event (struct execution_control_state *ecs)
4249 struct regcache *regcache;
4252 if (!ptid_equal (ecs->ptid, inferior_ptid))
4253 context_switch (ecs->ptid);
4255 regcache = get_thread_regcache (ecs->ptid);
4256 syscall_number = ecs->ws.value.syscall_number;
4257 stop_pc = regcache_read_pc (regcache);
4259 if (catch_syscall_enabled () > 0
4260 && catching_syscall_number (syscall_number) > 0)
4263 fprintf_unfiltered (gdb_stdlog, "infrun: syscall number = '%d'\n",
4266 ecs->event_thread->control.stop_bpstat
4267 = bpstat_stop_status (get_regcache_aspace (regcache),
4268 stop_pc, ecs->ptid, &ecs->ws);
4270 if (handle_stop_requested (ecs))
4273 if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
4275 /* Catchpoint hit. */
4280 if (handle_stop_requested (ecs))
4283 /* If no catchpoint triggered for this, then keep going. */
4288 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4291 fill_in_stop_func (struct gdbarch *gdbarch,
4292 struct execution_control_state *ecs)
4294 if (!ecs->stop_func_filled_in)
4296 /* Don't care about return value; stop_func_start and stop_func_name
4297 will both be 0 if it doesn't work. */
4298 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
4299 &ecs->stop_func_start, &ecs->stop_func_end);
4300 ecs->stop_func_start
4301 += gdbarch_deprecated_function_start_offset (gdbarch);
4303 if (gdbarch_skip_entrypoint_p (gdbarch))
4304 ecs->stop_func_start = gdbarch_skip_entrypoint (gdbarch,
4305 ecs->stop_func_start);
4307 ecs->stop_func_filled_in = 1;
4312 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4314 static enum stop_kind
4315 get_inferior_stop_soon (ptid_t ptid)
4317 struct inferior *inf = find_inferior_ptid (ptid);
4319 gdb_assert (inf != NULL);
4320 return inf->control.stop_soon;
4323 /* Wait for one event. Store the resulting waitstatus in WS, and
4324 return the event ptid. */
4327 wait_one (struct target_waitstatus *ws)
4330 ptid_t wait_ptid = minus_one_ptid;
4332 overlay_cache_invalid = 1;
4334 /* Flush target cache before starting to handle each event.
4335 Target was running and cache could be stale. This is just a
4336 heuristic. Running threads may modify target memory, but we
4337 don't get any event. */
4338 target_dcache_invalidate ();
4340 if (deprecated_target_wait_hook)
4341 event_ptid = deprecated_target_wait_hook (wait_ptid, ws, 0);
4343 event_ptid = target_wait (wait_ptid, ws, 0);
4346 print_target_wait_results (wait_ptid, event_ptid, ws);
4351 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4352 instead of the current thread. */
4353 #define THREAD_STOPPED_BY(REASON) \
4355 thread_stopped_by_ ## REASON (ptid_t ptid) \
4357 scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid); \
4358 inferior_ptid = ptid; \
4360 return target_stopped_by_ ## REASON (); \
4363 /* Generate thread_stopped_by_watchpoint. */
4364 THREAD_STOPPED_BY (watchpoint)
4365 /* Generate thread_stopped_by_sw_breakpoint. */
4366 THREAD_STOPPED_BY (sw_breakpoint)
4367 /* Generate thread_stopped_by_hw_breakpoint. */
4368 THREAD_STOPPED_BY (hw_breakpoint)
4370 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4373 switch_to_thread_cleanup (void *ptid_p)
4375 ptid_t ptid = *(ptid_t *) ptid_p;
4377 switch_to_thread (ptid);
4380 /* Save the thread's event and stop reason to process it later. */
4383 save_waitstatus (struct thread_info *tp, struct target_waitstatus *ws)
4385 struct regcache *regcache;
4386 struct address_space *aspace;
4390 std::string statstr = target_waitstatus_to_string (ws);
4392 fprintf_unfiltered (gdb_stdlog,
4393 "infrun: saving status %s for %d.%ld.%ld\n",
4395 ptid_get_pid (tp->ptid),
4396 ptid_get_lwp (tp->ptid),
4397 ptid_get_tid (tp->ptid));
4400 /* Record for later. */
4401 tp->suspend.waitstatus = *ws;
4402 tp->suspend.waitstatus_pending_p = 1;
4404 regcache = get_thread_regcache (tp->ptid);
4405 aspace = get_regcache_aspace (regcache);
4407 if (ws->kind == TARGET_WAITKIND_STOPPED
4408 && ws->value.sig == GDB_SIGNAL_TRAP)
4410 CORE_ADDR pc = regcache_read_pc (regcache);
4412 adjust_pc_after_break (tp, &tp->suspend.waitstatus);
4414 if (thread_stopped_by_watchpoint (tp->ptid))
4416 tp->suspend.stop_reason
4417 = TARGET_STOPPED_BY_WATCHPOINT;
4419 else if (target_supports_stopped_by_sw_breakpoint ()
4420 && thread_stopped_by_sw_breakpoint (tp->ptid))
4422 tp->suspend.stop_reason
4423 = TARGET_STOPPED_BY_SW_BREAKPOINT;
4425 else if (target_supports_stopped_by_hw_breakpoint ()
4426 && thread_stopped_by_hw_breakpoint (tp->ptid))
4428 tp->suspend.stop_reason
4429 = TARGET_STOPPED_BY_HW_BREAKPOINT;
4431 else if (!target_supports_stopped_by_hw_breakpoint ()
4432 && hardware_breakpoint_inserted_here_p (aspace,
4435 tp->suspend.stop_reason
4436 = TARGET_STOPPED_BY_HW_BREAKPOINT;
4438 else if (!target_supports_stopped_by_sw_breakpoint ()
4439 && software_breakpoint_inserted_here_p (aspace,
4442 tp->suspend.stop_reason
4443 = TARGET_STOPPED_BY_SW_BREAKPOINT;
4445 else if (!thread_has_single_step_breakpoints_set (tp)
4446 && currently_stepping (tp))
4448 tp->suspend.stop_reason
4449 = TARGET_STOPPED_BY_SINGLE_STEP;
4454 /* A cleanup that disables thread create/exit events. */
4457 disable_thread_events (void *arg)
4459 target_thread_events (0);
4465 stop_all_threads (void)
4467 /* We may need multiple passes to discover all threads. */
4471 struct cleanup *old_chain;
4473 gdb_assert (target_is_non_stop_p ());
4476 fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads\n");
4478 entry_ptid = inferior_ptid;
4479 old_chain = make_cleanup (switch_to_thread_cleanup, &entry_ptid);
4481 target_thread_events (1);
4482 make_cleanup (disable_thread_events, NULL);
4484 /* Request threads to stop, and then wait for the stops. Because
4485 threads we already know about can spawn more threads while we're
4486 trying to stop them, and we only learn about new threads when we
4487 update the thread list, do this in a loop, and keep iterating
4488 until two passes find no threads that need to be stopped. */
4489 for (pass = 0; pass < 2; pass++, iterations++)
4492 fprintf_unfiltered (gdb_stdlog,
4493 "infrun: stop_all_threads, pass=%d, "
4494 "iterations=%d\n", pass, iterations);
4498 struct target_waitstatus ws;
4500 struct thread_info *t;
4502 update_thread_list ();
4504 /* Go through all threads looking for threads that we need
4505 to tell the target to stop. */
4506 ALL_NON_EXITED_THREADS (t)
4510 /* If already stopping, don't request a stop again.
4511 We just haven't seen the notification yet. */
4512 if (!t->stop_requested)
4515 fprintf_unfiltered (gdb_stdlog,
4516 "infrun: %s executing, "
4518 target_pid_to_str (t->ptid));
4519 target_stop (t->ptid);
4520 t->stop_requested = 1;
4525 fprintf_unfiltered (gdb_stdlog,
4526 "infrun: %s executing, "
4527 "already stopping\n",
4528 target_pid_to_str (t->ptid));
4531 if (t->stop_requested)
4537 fprintf_unfiltered (gdb_stdlog,
4538 "infrun: %s not executing\n",
4539 target_pid_to_str (t->ptid));
4541 /* The thread may be not executing, but still be
4542 resumed with a pending status to process. */
4550 /* If we find new threads on the second iteration, restart
4551 over. We want to see two iterations in a row with all
4556 event_ptid = wait_one (&ws);
4557 if (ws.kind == TARGET_WAITKIND_NO_RESUMED)
4559 /* All resumed threads exited. */
4561 else if (ws.kind == TARGET_WAITKIND_THREAD_EXITED
4562 || ws.kind == TARGET_WAITKIND_EXITED
4563 || ws.kind == TARGET_WAITKIND_SIGNALLED)
4567 ptid_t ptid = pid_to_ptid (ws.value.integer);
4569 fprintf_unfiltered (gdb_stdlog,
4570 "infrun: %s exited while "
4571 "stopping threads\n",
4572 target_pid_to_str (ptid));
4577 struct inferior *inf;
4579 t = find_thread_ptid (event_ptid);
4581 t = add_thread (event_ptid);
4583 t->stop_requested = 0;
4586 t->control.may_range_step = 0;
4588 /* This may be the first time we see the inferior report
4590 inf = find_inferior_ptid (event_ptid);
4591 if (inf->needs_setup)
4593 switch_to_thread_no_regs (t);
4597 if (ws.kind == TARGET_WAITKIND_STOPPED
4598 && ws.value.sig == GDB_SIGNAL_0)
4600 /* We caught the event that we intended to catch, so
4601 there's no event pending. */
4602 t->suspend.waitstatus.kind = TARGET_WAITKIND_IGNORE;
4603 t->suspend.waitstatus_pending_p = 0;
4605 if (displaced_step_fixup (t->ptid, GDB_SIGNAL_0) < 0)
4607 /* Add it back to the step-over queue. */
4610 fprintf_unfiltered (gdb_stdlog,
4611 "infrun: displaced-step of %s "
4612 "canceled: adding back to the "
4613 "step-over queue\n",
4614 target_pid_to_str (t->ptid));
4616 t->control.trap_expected = 0;
4617 thread_step_over_chain_enqueue (t);
4622 enum gdb_signal sig;
4623 struct regcache *regcache;
4627 std::string statstr = target_waitstatus_to_string (&ws);
4629 fprintf_unfiltered (gdb_stdlog,
4630 "infrun: target_wait %s, saving "
4631 "status for %d.%ld.%ld\n",
4633 ptid_get_pid (t->ptid),
4634 ptid_get_lwp (t->ptid),
4635 ptid_get_tid (t->ptid));
4638 /* Record for later. */
4639 save_waitstatus (t, &ws);
4641 sig = (ws.kind == TARGET_WAITKIND_STOPPED
4642 ? ws.value.sig : GDB_SIGNAL_0);
4644 if (displaced_step_fixup (t->ptid, sig) < 0)
4646 /* Add it back to the step-over queue. */
4647 t->control.trap_expected = 0;
4648 thread_step_over_chain_enqueue (t);
4651 regcache = get_thread_regcache (t->ptid);
4652 t->suspend.stop_pc = regcache_read_pc (regcache);
4656 fprintf_unfiltered (gdb_stdlog,
4657 "infrun: saved stop_pc=%s for %s "
4658 "(currently_stepping=%d)\n",
4659 paddress (target_gdbarch (),
4660 t->suspend.stop_pc),
4661 target_pid_to_str (t->ptid),
4662 currently_stepping (t));
4669 do_cleanups (old_chain);
4672 fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads done\n");
4675 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4678 handle_no_resumed (struct execution_control_state *ecs)
4680 struct inferior *inf;
4681 struct thread_info *thread;
4683 if (target_can_async_p ())
4690 if (ui->prompt_state == PROMPT_BLOCKED)
4698 /* There were no unwaited-for children left in the target, but,
4699 we're not synchronously waiting for events either. Just
4703 fprintf_unfiltered (gdb_stdlog,
4704 "infrun: TARGET_WAITKIND_NO_RESUMED "
4705 "(ignoring: bg)\n");
4706 prepare_to_wait (ecs);
4711 /* Otherwise, if we were running a synchronous execution command, we
4712 may need to cancel it and give the user back the terminal.
4714 In non-stop mode, the target can't tell whether we've already
4715 consumed previous stop events, so it can end up sending us a
4716 no-resumed event like so:
4718 #0 - thread 1 is left stopped
4720 #1 - thread 2 is resumed and hits breakpoint
4721 -> TARGET_WAITKIND_STOPPED
4723 #2 - thread 3 is resumed and exits
4724 this is the last resumed thread, so
4725 -> TARGET_WAITKIND_NO_RESUMED
4727 #3 - gdb processes stop for thread 2 and decides to re-resume
4730 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4731 thread 2 is now resumed, so the event should be ignored.
4733 IOW, if the stop for thread 2 doesn't end a foreground command,
4734 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4735 event. But it could be that the event meant that thread 2 itself
4736 (or whatever other thread was the last resumed thread) exited.
4738 To address this we refresh the thread list and check whether we
4739 have resumed threads _now_. In the example above, this removes
4740 thread 3 from the thread list. If thread 2 was re-resumed, we
4741 ignore this event. If we find no thread resumed, then we cancel
4742 the synchronous command show "no unwaited-for " to the user. */
4743 update_thread_list ();
4745 ALL_NON_EXITED_THREADS (thread)
4747 if (thread->executing
4748 || thread->suspend.waitstatus_pending_p)
4750 /* There were no unwaited-for children left in the target at
4751 some point, but there are now. Just ignore. */
4753 fprintf_unfiltered (gdb_stdlog,
4754 "infrun: TARGET_WAITKIND_NO_RESUMED "
4755 "(ignoring: found resumed)\n");
4756 prepare_to_wait (ecs);
4761 /* Note however that we may find no resumed thread because the whole
4762 process exited meanwhile (thus updating the thread list results
4763 in an empty thread list). In this case we know we'll be getting
4764 a process exit event shortly. */
4770 thread = any_live_thread_of_process (inf->pid);
4774 fprintf_unfiltered (gdb_stdlog,
4775 "infrun: TARGET_WAITKIND_NO_RESUMED "
4776 "(expect process exit)\n");
4777 prepare_to_wait (ecs);
4782 /* Go ahead and report the event. */
4786 /* Given an execution control state that has been freshly filled in by
4787 an event from the inferior, figure out what it means and take
4790 The alternatives are:
4792 1) stop_waiting and return; to really stop and return to the
4795 2) keep_going and return; to wait for the next event (set
4796 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4800 handle_inferior_event_1 (struct execution_control_state *ecs)
4802 enum stop_kind stop_soon;
4804 if (ecs->ws.kind == TARGET_WAITKIND_IGNORE)
4806 /* We had an event in the inferior, but we are not interested in
4807 handling it at this level. The lower layers have already
4808 done what needs to be done, if anything.
4810 One of the possible circumstances for this is when the
4811 inferior produces output for the console. The inferior has
4812 not stopped, and we are ignoring the event. Another possible
4813 circumstance is any event which the lower level knows will be
4814 reported multiple times without an intervening resume. */
4816 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n");
4817 prepare_to_wait (ecs);
4821 if (ecs->ws.kind == TARGET_WAITKIND_THREAD_EXITED)
4824 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4825 prepare_to_wait (ecs);
4829 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED
4830 && handle_no_resumed (ecs))
4833 /* Cache the last pid/waitstatus. */
4834 set_last_target_status (ecs->ptid, ecs->ws);
4836 /* Always clear state belonging to the previous time we stopped. */
4837 stop_stack_dummy = STOP_NONE;
4839 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED)
4841 /* No unwaited-for children left. IOW, all resumed children
4844 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4846 stop_print_frame = 0;
4851 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
4852 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
4854 ecs->event_thread = find_thread_ptid (ecs->ptid);
4855 /* If it's a new thread, add it to the thread database. */
4856 if (ecs->event_thread == NULL)
4857 ecs->event_thread = add_thread (ecs->ptid);
4859 /* Disable range stepping. If the next step request could use a
4860 range, this will be end up re-enabled then. */
4861 ecs->event_thread->control.may_range_step = 0;
4864 /* Dependent on valid ECS->EVENT_THREAD. */
4865 adjust_pc_after_break (ecs->event_thread, &ecs->ws);
4867 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4868 reinit_frame_cache ();
4870 breakpoint_retire_moribund ();
4872 /* First, distinguish signals caused by the debugger from signals
4873 that have to do with the program's own actions. Note that
4874 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4875 on the operating system version. Here we detect when a SIGILL or
4876 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4877 something similar for SIGSEGV, since a SIGSEGV will be generated
4878 when we're trying to execute a breakpoint instruction on a
4879 non-executable stack. This happens for call dummy breakpoints
4880 for architectures like SPARC that place call dummies on the
4882 if (ecs->ws.kind == TARGET_WAITKIND_STOPPED
4883 && (ecs->ws.value.sig == GDB_SIGNAL_ILL
4884 || ecs->ws.value.sig == GDB_SIGNAL_SEGV
4885 || ecs->ws.value.sig == GDB_SIGNAL_EMT))
4887 struct regcache *regcache = get_thread_regcache (ecs->ptid);
4889 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache),
4890 regcache_read_pc (regcache)))
4893 fprintf_unfiltered (gdb_stdlog,
4894 "infrun: Treating signal as SIGTRAP\n");
4895 ecs->ws.value.sig = GDB_SIGNAL_TRAP;
4899 /* Mark the non-executing threads accordingly. In all-stop, all
4900 threads of all processes are stopped when we get any event
4901 reported. In non-stop mode, only the event thread stops. */
4905 if (!target_is_non_stop_p ())
4906 mark_ptid = minus_one_ptid;
4907 else if (ecs->ws.kind == TARGET_WAITKIND_SIGNALLED
4908 || ecs->ws.kind == TARGET_WAITKIND_EXITED)
4910 /* If we're handling a process exit in non-stop mode, even
4911 though threads haven't been deleted yet, one would think
4912 that there is nothing to do, as threads of the dead process
4913 will be soon deleted, and threads of any other process were
4914 left running. However, on some targets, threads survive a
4915 process exit event. E.g., for the "checkpoint" command,
4916 when the current checkpoint/fork exits, linux-fork.c
4917 automatically switches to another fork from within
4918 target_mourn_inferior, by associating the same
4919 inferior/thread to another fork. We haven't mourned yet at
4920 this point, but we must mark any threads left in the
4921 process as not-executing so that finish_thread_state marks
4922 them stopped (in the user's perspective) if/when we present
4923 the stop to the user. */
4924 mark_ptid = pid_to_ptid (ptid_get_pid (ecs->ptid));
4927 mark_ptid = ecs->ptid;
4929 set_executing (mark_ptid, 0);
4931 /* Likewise the resumed flag. */
4932 set_resumed (mark_ptid, 0);
4935 switch (ecs->ws.kind)
4937 case TARGET_WAITKIND_LOADED:
4939 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n");
4940 if (!ptid_equal (ecs->ptid, inferior_ptid))
4941 context_switch (ecs->ptid);
4942 /* Ignore gracefully during startup of the inferior, as it might
4943 be the shell which has just loaded some objects, otherwise
4944 add the symbols for the newly loaded objects. Also ignore at
4945 the beginning of an attach or remote session; we will query
4946 the full list of libraries once the connection is
4949 stop_soon = get_inferior_stop_soon (ecs->ptid);
4950 if (stop_soon == NO_STOP_QUIETLY)
4952 struct regcache *regcache;
4954 regcache = get_thread_regcache (ecs->ptid);
4956 handle_solib_event ();
4958 ecs->event_thread->control.stop_bpstat
4959 = bpstat_stop_status (get_regcache_aspace (regcache),
4960 stop_pc, ecs->ptid, &ecs->ws);
4962 if (handle_stop_requested (ecs))
4965 if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
4967 /* A catchpoint triggered. */
4968 process_event_stop_test (ecs);
4972 /* If requested, stop when the dynamic linker notifies
4973 gdb of events. This allows the user to get control
4974 and place breakpoints in initializer routines for
4975 dynamically loaded objects (among other things). */
4976 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
4977 if (stop_on_solib_events)
4979 /* Make sure we print "Stopped due to solib-event" in
4981 stop_print_frame = 1;
4988 /* If we are skipping through a shell, or through shared library
4989 loading that we aren't interested in, resume the program. If
4990 we're running the program normally, also resume. */
4991 if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY)
4993 /* Loading of shared libraries might have changed breakpoint
4994 addresses. Make sure new breakpoints are inserted. */
4995 if (stop_soon == NO_STOP_QUIETLY)
4996 insert_breakpoints ();
4997 resume (GDB_SIGNAL_0);
4998 prepare_to_wait (ecs);
5002 /* But stop if we're attaching or setting up a remote
5004 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
5005 || stop_soon == STOP_QUIETLY_REMOTE)
5008 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
5013 internal_error (__FILE__, __LINE__,
5014 _("unhandled stop_soon: %d"), (int) stop_soon);
5016 case TARGET_WAITKIND_SPURIOUS:
5018 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
5019 if (handle_stop_requested (ecs))
5021 if (!ptid_equal (ecs->ptid, inferior_ptid))
5022 context_switch (ecs->ptid);
5023 resume (GDB_SIGNAL_0);
5024 prepare_to_wait (ecs);
5027 case TARGET_WAITKIND_THREAD_CREATED:
5029 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
5030 if (handle_stop_requested (ecs))
5032 if (!ptid_equal (ecs->ptid, inferior_ptid))
5033 context_switch (ecs->ptid);
5034 if (!switch_back_to_stepped_thread (ecs))
5038 case TARGET_WAITKIND_EXITED:
5039 case TARGET_WAITKIND_SIGNALLED:
5042 if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
5043 fprintf_unfiltered (gdb_stdlog,
5044 "infrun: TARGET_WAITKIND_EXITED\n");
5046 fprintf_unfiltered (gdb_stdlog,
5047 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5050 inferior_ptid = ecs->ptid;
5051 set_current_inferior (find_inferior_ptid (ecs->ptid));
5052 set_current_program_space (current_inferior ()->pspace);
5053 handle_vfork_child_exec_or_exit (0);
5054 target_terminal::ours (); /* Must do this before mourn anyway. */
5056 /* Clearing any previous state of convenience variables. */
5057 clear_exit_convenience_vars ();
5059 if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
5061 /* Record the exit code in the convenience variable $_exitcode, so
5062 that the user can inspect this again later. */
5063 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5064 (LONGEST) ecs->ws.value.integer);
5066 /* Also record this in the inferior itself. */
5067 current_inferior ()->has_exit_code = 1;
5068 current_inferior ()->exit_code = (LONGEST) ecs->ws.value.integer;
5070 /* Support the --return-child-result option. */
5071 return_child_result_value = ecs->ws.value.integer;
5073 observer_notify_exited (ecs->ws.value.integer);
5077 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5078 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5080 if (gdbarch_gdb_signal_to_target_p (gdbarch))
5082 /* Set the value of the internal variable $_exitsignal,
5083 which holds the signal uncaught by the inferior. */
5084 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5085 gdbarch_gdb_signal_to_target (gdbarch,
5086 ecs->ws.value.sig));
5090 /* We don't have access to the target's method used for
5091 converting between signal numbers (GDB's internal
5092 representation <-> target's representation).
5093 Therefore, we cannot do a good job at displaying this
5094 information to the user. It's better to just warn
5095 her about it (if infrun debugging is enabled), and
5098 fprintf_filtered (gdb_stdlog, _("\
5099 Cannot fill $_exitsignal with the correct signal number.\n"));
5102 observer_notify_signal_exited (ecs->ws.value.sig);
5105 gdb_flush (gdb_stdout);
5106 target_mourn_inferior (inferior_ptid);
5107 stop_print_frame = 0;
5111 /* The following are the only cases in which we keep going;
5112 the above cases end in a continue or goto. */
5113 case TARGET_WAITKIND_FORKED:
5114 case TARGET_WAITKIND_VFORKED:
5117 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
5118 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
5120 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_VFORKED\n");
5123 /* Check whether the inferior is displaced stepping. */
5125 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5126 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5128 /* If checking displaced stepping is supported, and thread
5129 ecs->ptid is displaced stepping. */
5130 if (displaced_step_in_progress_thread (ecs->ptid))
5132 struct inferior *parent_inf
5133 = find_inferior_ptid (ecs->ptid);
5134 struct regcache *child_regcache;
5135 CORE_ADDR parent_pc;
5137 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5138 indicating that the displaced stepping of syscall instruction
5139 has been done. Perform cleanup for parent process here. Note
5140 that this operation also cleans up the child process for vfork,
5141 because their pages are shared. */
5142 displaced_step_fixup (ecs->ptid, GDB_SIGNAL_TRAP);
5143 /* Start a new step-over in another thread if there's one
5147 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
5149 struct displaced_step_inferior_state *displaced
5150 = get_displaced_stepping_state (ptid_get_pid (ecs->ptid));
5152 /* Restore scratch pad for child process. */
5153 displaced_step_restore (displaced, ecs->ws.value.related_pid);
5156 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5157 the child's PC is also within the scratchpad. Set the child's PC
5158 to the parent's PC value, which has already been fixed up.
5159 FIXME: we use the parent's aspace here, although we're touching
5160 the child, because the child hasn't been added to the inferior
5161 list yet at this point. */
5164 = get_thread_arch_aspace_regcache (ecs->ws.value.related_pid,
5166 parent_inf->aspace);
5167 /* Read PC value of parent process. */
5168 parent_pc = regcache_read_pc (regcache);
5170 if (debug_displaced)
5171 fprintf_unfiltered (gdb_stdlog,
5172 "displaced: write child pc from %s to %s\n",
5174 regcache_read_pc (child_regcache)),
5175 paddress (gdbarch, parent_pc));
5177 regcache_write_pc (child_regcache, parent_pc);
5181 if (!ptid_equal (ecs->ptid, inferior_ptid))
5182 context_switch (ecs->ptid);
5184 /* Immediately detach breakpoints from the child before there's
5185 any chance of letting the user delete breakpoints from the
5186 breakpoint lists. If we don't do this early, it's easy to
5187 leave left over traps in the child, vis: "break foo; catch
5188 fork; c; <fork>; del; c; <child calls foo>". We only follow
5189 the fork on the last `continue', and by that time the
5190 breakpoint at "foo" is long gone from the breakpoint table.
5191 If we vforked, then we don't need to unpatch here, since both
5192 parent and child are sharing the same memory pages; we'll
5193 need to unpatch at follow/detach time instead to be certain
5194 that new breakpoints added between catchpoint hit time and
5195 vfork follow are detached. */
5196 if (ecs->ws.kind != TARGET_WAITKIND_VFORKED)
5198 /* This won't actually modify the breakpoint list, but will
5199 physically remove the breakpoints from the child. */
5200 detach_breakpoints (ecs->ws.value.related_pid);
5203 delete_just_stopped_threads_single_step_breakpoints ();
5205 /* In case the event is caught by a catchpoint, remember that
5206 the event is to be followed at the next resume of the thread,
5207 and not immediately. */
5208 ecs->event_thread->pending_follow = ecs->ws;
5210 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5212 ecs->event_thread->control.stop_bpstat
5213 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5214 stop_pc, ecs->ptid, &ecs->ws);
5216 if (handle_stop_requested (ecs))
5219 /* If no catchpoint triggered for this, then keep going. Note
5220 that we're interested in knowing the bpstat actually causes a
5221 stop, not just if it may explain the signal. Software
5222 watchpoints, for example, always appear in the bpstat. */
5223 if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
5229 = (follow_fork_mode_string == follow_fork_mode_child);
5231 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5233 should_resume = follow_fork ();
5236 child = ecs->ws.value.related_pid;
5238 /* At this point, the parent is marked running, and the
5239 child is marked stopped. */
5241 /* If not resuming the parent, mark it stopped. */
5242 if (follow_child && !detach_fork && !non_stop && !sched_multi)
5243 set_running (parent, 0);
5245 /* If resuming the child, mark it running. */
5246 if (follow_child || (!detach_fork && (non_stop || sched_multi)))
5247 set_running (child, 1);
5249 /* In non-stop mode, also resume the other branch. */
5250 if (!detach_fork && (non_stop
5251 || (sched_multi && target_is_non_stop_p ())))
5254 switch_to_thread (parent);
5256 switch_to_thread (child);
5258 ecs->event_thread = inferior_thread ();
5259 ecs->ptid = inferior_ptid;
5264 switch_to_thread (child);
5266 switch_to_thread (parent);
5268 ecs->event_thread = inferior_thread ();
5269 ecs->ptid = inferior_ptid;
5277 process_event_stop_test (ecs);
5280 case TARGET_WAITKIND_VFORK_DONE:
5281 /* Done with the shared memory region. Re-insert breakpoints in
5282 the parent, and keep going. */
5285 fprintf_unfiltered (gdb_stdlog,
5286 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5288 if (!ptid_equal (ecs->ptid, inferior_ptid))
5289 context_switch (ecs->ptid);
5291 current_inferior ()->waiting_for_vfork_done = 0;
5292 current_inferior ()->pspace->breakpoints_not_allowed = 0;
5294 if (handle_stop_requested (ecs))
5297 /* This also takes care of reinserting breakpoints in the
5298 previously locked inferior. */
5302 case TARGET_WAITKIND_EXECD:
5304 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n");
5306 /* Note we can't read registers yet (the stop_pc), because we
5307 don't yet know the inferior's post-exec architecture.
5308 'stop_pc' is explicitly read below instead. */
5309 if (!ptid_equal (ecs->ptid, inferior_ptid))
5310 switch_to_thread_no_regs (ecs->event_thread);
5312 /* Do whatever is necessary to the parent branch of the vfork. */
5313 handle_vfork_child_exec_or_exit (1);
5315 /* This causes the eventpoints and symbol table to be reset.
5316 Must do this now, before trying to determine whether to
5318 follow_exec (inferior_ptid, ecs->ws.value.execd_pathname);
5320 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5322 /* In follow_exec we may have deleted the original thread and
5323 created a new one. Make sure that the event thread is the
5324 execd thread for that case (this is a nop otherwise). */
5325 ecs->event_thread = inferior_thread ();
5327 ecs->event_thread->control.stop_bpstat
5328 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5329 stop_pc, ecs->ptid, &ecs->ws);
5331 /* Note that this may be referenced from inside
5332 bpstat_stop_status above, through inferior_has_execd. */
5333 xfree (ecs->ws.value.execd_pathname);
5334 ecs->ws.value.execd_pathname = NULL;
5336 if (handle_stop_requested (ecs))
5339 /* If no catchpoint triggered for this, then keep going. */
5340 if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
5342 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5346 process_event_stop_test (ecs);
5349 /* Be careful not to try to gather much state about a thread
5350 that's in a syscall. It's frequently a losing proposition. */
5351 case TARGET_WAITKIND_SYSCALL_ENTRY:
5353 fprintf_unfiltered (gdb_stdlog,
5354 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5355 /* Getting the current syscall number. */
5356 if (handle_syscall_event (ecs) == 0)
5357 process_event_stop_test (ecs);
5360 /* Before examining the threads further, step this thread to
5361 get it entirely out of the syscall. (We get notice of the
5362 event when the thread is just on the verge of exiting a
5363 syscall. Stepping one instruction seems to get it back
5365 case TARGET_WAITKIND_SYSCALL_RETURN:
5367 fprintf_unfiltered (gdb_stdlog,
5368 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5369 if (handle_syscall_event (ecs) == 0)
5370 process_event_stop_test (ecs);
5373 case TARGET_WAITKIND_STOPPED:
5375 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n");
5376 handle_signal_stop (ecs);
5379 case TARGET_WAITKIND_NO_HISTORY:
5381 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5382 /* Reverse execution: target ran out of history info. */
5384 /* Switch to the stopped thread. */
5385 if (!ptid_equal (ecs->ptid, inferior_ptid))
5386 context_switch (ecs->ptid);
5388 fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n");
5390 delete_just_stopped_threads_single_step_breakpoints ();
5391 stop_pc = regcache_read_pc (get_thread_regcache (inferior_ptid));
5393 if (handle_stop_requested (ecs))
5396 observer_notify_no_history ();
5402 /* A wrapper around handle_inferior_event_1, which also makes sure
5403 that all temporary struct value objects that were created during
5404 the handling of the event get deleted at the end. */
5407 handle_inferior_event (struct execution_control_state *ecs)
5409 struct value *mark = value_mark ();
5411 handle_inferior_event_1 (ecs);
5412 /* Purge all temporary values created during the event handling,
5413 as it could be a long time before we return to the command level
5414 where such values would otherwise be purged. */
5415 value_free_to_mark (mark);
5418 /* Restart threads back to what they were trying to do back when we
5419 paused them for an in-line step-over. The EVENT_THREAD thread is
5423 restart_threads (struct thread_info *event_thread)
5425 struct thread_info *tp;
5427 /* In case the instruction just stepped spawned a new thread. */
5428 update_thread_list ();
5430 ALL_NON_EXITED_THREADS (tp)
5432 if (tp == event_thread)
5435 fprintf_unfiltered (gdb_stdlog,
5436 "infrun: restart threads: "
5437 "[%s] is event thread\n",
5438 target_pid_to_str (tp->ptid));
5442 if (!(tp->state == THREAD_RUNNING || tp->control.in_infcall))
5445 fprintf_unfiltered (gdb_stdlog,
5446 "infrun: restart threads: "
5447 "[%s] not meant to be running\n",
5448 target_pid_to_str (tp->ptid));
5455 fprintf_unfiltered (gdb_stdlog,
5456 "infrun: restart threads: [%s] resumed\n",
5457 target_pid_to_str (tp->ptid));
5458 gdb_assert (tp->executing || tp->suspend.waitstatus_pending_p);
5462 if (thread_is_in_step_over_chain (tp))
5465 fprintf_unfiltered (gdb_stdlog,
5466 "infrun: restart threads: "
5467 "[%s] needs step-over\n",
5468 target_pid_to_str (tp->ptid));
5469 gdb_assert (!tp->resumed);
5474 if (tp->suspend.waitstatus_pending_p)
5477 fprintf_unfiltered (gdb_stdlog,
5478 "infrun: restart threads: "
5479 "[%s] has pending status\n",
5480 target_pid_to_str (tp->ptid));
5485 gdb_assert (!tp->stop_requested);
5487 /* If some thread needs to start a step-over at this point, it
5488 should still be in the step-over queue, and thus skipped
5490 if (thread_still_needs_step_over (tp))
5492 internal_error (__FILE__, __LINE__,
5493 "thread [%s] needs a step-over, but not in "
5494 "step-over queue\n",
5495 target_pid_to_str (tp->ptid));
5498 if (currently_stepping (tp))
5501 fprintf_unfiltered (gdb_stdlog,
5502 "infrun: restart threads: [%s] was stepping\n",
5503 target_pid_to_str (tp->ptid));
5504 keep_going_stepped_thread (tp);
5508 struct execution_control_state ecss;
5509 struct execution_control_state *ecs = &ecss;
5512 fprintf_unfiltered (gdb_stdlog,
5513 "infrun: restart threads: [%s] continuing\n",
5514 target_pid_to_str (tp->ptid));
5515 reset_ecs (ecs, tp);
5516 switch_to_thread (tp->ptid);
5517 keep_going_pass_signal (ecs);
5522 /* Callback for iterate_over_threads. Find a resumed thread that has
5523 a pending waitstatus. */
5526 resumed_thread_with_pending_status (struct thread_info *tp,
5530 && tp->suspend.waitstatus_pending_p);
5533 /* Called when we get an event that may finish an in-line or
5534 out-of-line (displaced stepping) step-over started previously.
5535 Return true if the event is processed and we should go back to the
5536 event loop; false if the caller should continue processing the
5540 finish_step_over (struct execution_control_state *ecs)
5542 int had_step_over_info;
5544 displaced_step_fixup (ecs->ptid,
5545 ecs->event_thread->suspend.stop_signal);
5547 had_step_over_info = step_over_info_valid_p ();
5549 if (had_step_over_info)
5551 /* If we're stepping over a breakpoint with all threads locked,
5552 then only the thread that was stepped should be reporting
5554 gdb_assert (ecs->event_thread->control.trap_expected);
5556 clear_step_over_info ();
5559 if (!target_is_non_stop_p ())
5562 /* Start a new step-over in another thread if there's one that
5566 /* If we were stepping over a breakpoint before, and haven't started
5567 a new in-line step-over sequence, then restart all other threads
5568 (except the event thread). We can't do this in all-stop, as then
5569 e.g., we wouldn't be able to issue any other remote packet until
5570 these other threads stop. */
5571 if (had_step_over_info && !step_over_info_valid_p ())
5573 struct thread_info *pending;
5575 /* If we only have threads with pending statuses, the restart
5576 below won't restart any thread and so nothing re-inserts the
5577 breakpoint we just stepped over. But we need it inserted
5578 when we later process the pending events, otherwise if
5579 another thread has a pending event for this breakpoint too,
5580 we'd discard its event (because the breakpoint that
5581 originally caused the event was no longer inserted). */
5582 context_switch (ecs->ptid);
5583 insert_breakpoints ();
5585 restart_threads (ecs->event_thread);
5587 /* If we have events pending, go through handle_inferior_event
5588 again, picking up a pending event at random. This avoids
5589 thread starvation. */
5591 /* But not if we just stepped over a watchpoint in order to let
5592 the instruction execute so we can evaluate its expression.
5593 The set of watchpoints that triggered is recorded in the
5594 breakpoint objects themselves (see bp->watchpoint_triggered).
5595 If we processed another event first, that other event could
5596 clobber this info. */
5597 if (ecs->event_thread->stepping_over_watchpoint)
5600 pending = iterate_over_threads (resumed_thread_with_pending_status,
5602 if (pending != NULL)
5604 struct thread_info *tp = ecs->event_thread;
5605 struct regcache *regcache;
5609 fprintf_unfiltered (gdb_stdlog,
5610 "infrun: found resumed threads with "
5611 "pending events, saving status\n");
5614 gdb_assert (pending != tp);
5616 /* Record the event thread's event for later. */
5617 save_waitstatus (tp, &ecs->ws);
5618 /* This was cleared early, by handle_inferior_event. Set it
5619 so this pending event is considered by
5623 gdb_assert (!tp->executing);
5625 regcache = get_thread_regcache (tp->ptid);
5626 tp->suspend.stop_pc = regcache_read_pc (regcache);
5630 fprintf_unfiltered (gdb_stdlog,
5631 "infrun: saved stop_pc=%s for %s "
5632 "(currently_stepping=%d)\n",
5633 paddress (target_gdbarch (),
5634 tp->suspend.stop_pc),
5635 target_pid_to_str (tp->ptid),
5636 currently_stepping (tp));
5639 /* This in-line step-over finished; clear this so we won't
5640 start a new one. This is what handle_signal_stop would
5641 do, if we returned false. */
5642 tp->stepping_over_breakpoint = 0;
5644 /* Wake up the event loop again. */
5645 mark_async_event_handler (infrun_async_inferior_event_token);
5647 prepare_to_wait (ecs);
5655 /* Come here when the program has stopped with a signal. */
5658 handle_signal_stop (struct execution_control_state *ecs)
5660 struct frame_info *frame;
5661 struct gdbarch *gdbarch;
5662 int stopped_by_watchpoint;
5663 enum stop_kind stop_soon;
5666 gdb_assert (ecs->ws.kind == TARGET_WAITKIND_STOPPED);
5668 ecs->event_thread->suspend.stop_signal = ecs->ws.value.sig;
5670 /* Do we need to clean up the state of a thread that has
5671 completed a displaced single-step? (Doing so usually affects
5672 the PC, so do it here, before we set stop_pc.) */
5673 if (finish_step_over (ecs))
5676 /* If we either finished a single-step or hit a breakpoint, but
5677 the user wanted this thread to be stopped, pretend we got a
5678 SIG0 (generic unsignaled stop). */
5679 if (ecs->event_thread->stop_requested
5680 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
5681 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5683 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5687 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5688 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5689 scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
5691 inferior_ptid = ecs->ptid;
5693 fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = %s\n",
5694 paddress (gdbarch, stop_pc));
5695 if (target_stopped_by_watchpoint ())
5699 fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n");
5701 if (target_stopped_data_address (¤t_target, &addr))
5702 fprintf_unfiltered (gdb_stdlog,
5703 "infrun: stopped data address = %s\n",
5704 paddress (gdbarch, addr));
5706 fprintf_unfiltered (gdb_stdlog,
5707 "infrun: (no data address available)\n");
5711 /* This is originated from start_remote(), start_inferior() and
5712 shared libraries hook functions. */
5713 stop_soon = get_inferior_stop_soon (ecs->ptid);
5714 if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE)
5716 if (!ptid_equal (ecs->ptid, inferior_ptid))
5717 context_switch (ecs->ptid);
5719 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
5720 stop_print_frame = 1;
5725 /* This originates from attach_command(). We need to overwrite
5726 the stop_signal here, because some kernels don't ignore a
5727 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5728 See more comments in inferior.h. On the other hand, if we
5729 get a non-SIGSTOP, report it to the user - assume the backend
5730 will handle the SIGSTOP if it should show up later.
5732 Also consider that the attach is complete when we see a
5733 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5734 target extended-remote report it instead of a SIGSTOP
5735 (e.g. gdbserver). We already rely on SIGTRAP being our
5736 signal, so this is no exception.
5738 Also consider that the attach is complete when we see a
5739 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5740 the target to stop all threads of the inferior, in case the
5741 low level attach operation doesn't stop them implicitly. If
5742 they weren't stopped implicitly, then the stub will report a
5743 GDB_SIGNAL_0, meaning: stopped for no particular reason
5744 other than GDB's request. */
5745 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
5746 && (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_STOP
5747 || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5748 || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_0))
5750 stop_print_frame = 1;
5752 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5756 /* See if something interesting happened to the non-current thread. If
5757 so, then switch to that thread. */
5758 if (!ptid_equal (ecs->ptid, inferior_ptid))
5761 fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n");
5763 context_switch (ecs->ptid);
5765 if (deprecated_context_hook)
5766 deprecated_context_hook (ptid_to_global_thread_id (ecs->ptid));
5769 /* At this point, get hold of the now-current thread's frame. */
5770 frame = get_current_frame ();
5771 gdbarch = get_frame_arch (frame);
5773 /* Pull the single step breakpoints out of the target. */
5774 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
5776 struct regcache *regcache;
5777 struct address_space *aspace;
5780 regcache = get_thread_regcache (ecs->ptid);
5781 aspace = get_regcache_aspace (regcache);
5782 pc = regcache_read_pc (regcache);
5784 /* However, before doing so, if this single-step breakpoint was
5785 actually for another thread, set this thread up for moving
5787 if (!thread_has_single_step_breakpoint_here (ecs->event_thread,
5790 if (single_step_breakpoint_inserted_here_p (aspace, pc))
5794 fprintf_unfiltered (gdb_stdlog,
5795 "infrun: [%s] hit another thread's "
5796 "single-step breakpoint\n",
5797 target_pid_to_str (ecs->ptid));
5799 ecs->hit_singlestep_breakpoint = 1;
5806 fprintf_unfiltered (gdb_stdlog,
5807 "infrun: [%s] hit its "
5808 "single-step breakpoint\n",
5809 target_pid_to_str (ecs->ptid));
5813 delete_just_stopped_threads_single_step_breakpoints ();
5815 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5816 && ecs->event_thread->control.trap_expected
5817 && ecs->event_thread->stepping_over_watchpoint)
5818 stopped_by_watchpoint = 0;
5820 stopped_by_watchpoint = watchpoints_triggered (&ecs->ws);
5822 /* If necessary, step over this watchpoint. We'll be back to display
5824 if (stopped_by_watchpoint
5825 && (target_have_steppable_watchpoint
5826 || gdbarch_have_nonsteppable_watchpoint (gdbarch)))
5828 /* At this point, we are stopped at an instruction which has
5829 attempted to write to a piece of memory under control of
5830 a watchpoint. The instruction hasn't actually executed
5831 yet. If we were to evaluate the watchpoint expression
5832 now, we would get the old value, and therefore no change
5833 would seem to have occurred.
5835 In order to make watchpoints work `right', we really need
5836 to complete the memory write, and then evaluate the
5837 watchpoint expression. We do this by single-stepping the
5840 It may not be necessary to disable the watchpoint to step over
5841 it. For example, the PA can (with some kernel cooperation)
5842 single step over a watchpoint without disabling the watchpoint.
5844 It is far more common to need to disable a watchpoint to step
5845 the inferior over it. If we have non-steppable watchpoints,
5846 we must disable the current watchpoint; it's simplest to
5847 disable all watchpoints.
5849 Any breakpoint at PC must also be stepped over -- if there's
5850 one, it will have already triggered before the watchpoint
5851 triggered, and we either already reported it to the user, or
5852 it didn't cause a stop and we called keep_going. In either
5853 case, if there was a breakpoint at PC, we must be trying to
5855 ecs->event_thread->stepping_over_watchpoint = 1;
5860 ecs->event_thread->stepping_over_breakpoint = 0;
5861 ecs->event_thread->stepping_over_watchpoint = 0;
5862 bpstat_clear (&ecs->event_thread->control.stop_bpstat);
5863 ecs->event_thread->control.stop_step = 0;
5864 stop_print_frame = 1;
5865 stopped_by_random_signal = 0;
5867 /* Hide inlined functions starting here, unless we just performed stepi or
5868 nexti. After stepi and nexti, always show the innermost frame (not any
5869 inline function call sites). */
5870 if (ecs->event_thread->control.step_range_end != 1)
5872 struct address_space *aspace =
5873 get_regcache_aspace (get_thread_regcache (ecs->ptid));
5875 /* skip_inline_frames is expensive, so we avoid it if we can
5876 determine that the address is one where functions cannot have
5877 been inlined. This improves performance with inferiors that
5878 load a lot of shared libraries, because the solib event
5879 breakpoint is defined as the address of a function (i.e. not
5880 inline). Note that we have to check the previous PC as well
5881 as the current one to catch cases when we have just
5882 single-stepped off a breakpoint prior to reinstating it.
5883 Note that we're assuming that the code we single-step to is
5884 not inline, but that's not definitive: there's nothing
5885 preventing the event breakpoint function from containing
5886 inlined code, and the single-step ending up there. If the
5887 user had set a breakpoint on that inlined code, the missing
5888 skip_inline_frames call would break things. Fortunately
5889 that's an extremely unlikely scenario. */
5890 if (!pc_at_non_inline_function (aspace, stop_pc, &ecs->ws)
5891 && !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5892 && ecs->event_thread->control.trap_expected
5893 && pc_at_non_inline_function (aspace,
5894 ecs->event_thread->prev_pc,
5897 skip_inline_frames (ecs->ptid);
5899 /* Re-fetch current thread's frame in case that invalidated
5901 frame = get_current_frame ();
5902 gdbarch = get_frame_arch (frame);
5906 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5907 && ecs->event_thread->control.trap_expected
5908 && gdbarch_single_step_through_delay_p (gdbarch)
5909 && currently_stepping (ecs->event_thread))
5911 /* We're trying to step off a breakpoint. Turns out that we're
5912 also on an instruction that needs to be stepped multiple
5913 times before it's been fully executing. E.g., architectures
5914 with a delay slot. It needs to be stepped twice, once for
5915 the instruction and once for the delay slot. */
5916 int step_through_delay
5917 = gdbarch_single_step_through_delay (gdbarch, frame);
5919 if (debug_infrun && step_through_delay)
5920 fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n");
5921 if (ecs->event_thread->control.step_range_end == 0
5922 && step_through_delay)
5924 /* The user issued a continue when stopped at a breakpoint.
5925 Set up for another trap and get out of here. */
5926 ecs->event_thread->stepping_over_breakpoint = 1;
5930 else if (step_through_delay)
5932 /* The user issued a step when stopped at a breakpoint.
5933 Maybe we should stop, maybe we should not - the delay
5934 slot *might* correspond to a line of source. In any
5935 case, don't decide that here, just set
5936 ecs->stepping_over_breakpoint, making sure we
5937 single-step again before breakpoints are re-inserted. */
5938 ecs->event_thread->stepping_over_breakpoint = 1;
5942 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5943 handles this event. */
5944 ecs->event_thread->control.stop_bpstat
5945 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5946 stop_pc, ecs->ptid, &ecs->ws);
5948 /* Following in case break condition called a
5950 stop_print_frame = 1;
5952 /* This is where we handle "moribund" watchpoints. Unlike
5953 software breakpoints traps, hardware watchpoint traps are
5954 always distinguishable from random traps. If no high-level
5955 watchpoint is associated with the reported stop data address
5956 anymore, then the bpstat does not explain the signal ---
5957 simply make sure to ignore it if `stopped_by_watchpoint' is
5961 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5962 && !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
5964 && stopped_by_watchpoint)
5965 fprintf_unfiltered (gdb_stdlog,
5966 "infrun: no user watchpoint explains "
5967 "watchpoint SIGTRAP, ignoring\n");
5969 /* NOTE: cagney/2003-03-29: These checks for a random signal
5970 at one stage in the past included checks for an inferior
5971 function call's call dummy's return breakpoint. The original
5972 comment, that went with the test, read:
5974 ``End of a stack dummy. Some systems (e.g. Sony news) give
5975 another signal besides SIGTRAP, so check here as well as
5978 If someone ever tries to get call dummys on a
5979 non-executable stack to work (where the target would stop
5980 with something like a SIGSEGV), then those tests might need
5981 to be re-instated. Given, however, that the tests were only
5982 enabled when momentary breakpoints were not being used, I
5983 suspect that it won't be the case.
5985 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5986 be necessary for call dummies on a non-executable stack on
5989 /* See if the breakpoints module can explain the signal. */
5991 = !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
5992 ecs->event_thread->suspend.stop_signal);
5994 /* Maybe this was a trap for a software breakpoint that has since
5996 if (random_signal && target_stopped_by_sw_breakpoint ())
5998 if (program_breakpoint_here_p (gdbarch, stop_pc))
6000 struct regcache *regcache;
6003 /* Re-adjust PC to what the program would see if GDB was not
6005 regcache = get_thread_regcache (ecs->event_thread->ptid);
6006 decr_pc = gdbarch_decr_pc_after_break (gdbarch);
6009 gdb::optional<scoped_restore_tmpl<int>>
6010 restore_operation_disable;
6012 if (record_full_is_used ())
6013 restore_operation_disable.emplace
6014 (record_full_gdb_operation_disable_set ());
6016 regcache_write_pc (regcache, stop_pc + decr_pc);
6021 /* A delayed software breakpoint event. Ignore the trap. */
6023 fprintf_unfiltered (gdb_stdlog,
6024 "infrun: delayed software breakpoint "
6025 "trap, ignoring\n");
6030 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6031 has since been removed. */
6032 if (random_signal && target_stopped_by_hw_breakpoint ())
6034 /* A delayed hardware breakpoint event. Ignore the trap. */
6036 fprintf_unfiltered (gdb_stdlog,
6037 "infrun: delayed hardware breakpoint/watchpoint "
6038 "trap, ignoring\n");
6042 /* If not, perhaps stepping/nexting can. */
6044 random_signal = !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
6045 && currently_stepping (ecs->event_thread));
6047 /* Perhaps the thread hit a single-step breakpoint of _another_
6048 thread. Single-step breakpoints are transparent to the
6049 breakpoints module. */
6051 random_signal = !ecs->hit_singlestep_breakpoint;
6053 /* No? Perhaps we got a moribund watchpoint. */
6055 random_signal = !stopped_by_watchpoint;
6057 /* Always stop if the user explicitly requested this thread to
6059 if (ecs->event_thread->stop_requested)
6063 fprintf_unfiltered (gdb_stdlog, "infrun: user-requested stop\n");
6066 /* For the program's own signals, act according to
6067 the signal handling tables. */
6071 /* Signal not for debugging purposes. */
6072 struct inferior *inf = find_inferior_ptid (ecs->ptid);
6073 enum gdb_signal stop_signal = ecs->event_thread->suspend.stop_signal;
6076 fprintf_unfiltered (gdb_stdlog, "infrun: random signal (%s)\n",
6077 gdb_signal_to_symbol_string (stop_signal));
6079 stopped_by_random_signal = 1;
6081 /* Always stop on signals if we're either just gaining control
6082 of the program, or the user explicitly requested this thread
6083 to remain stopped. */
6084 if (stop_soon != NO_STOP_QUIETLY
6085 || ecs->event_thread->stop_requested
6087 && signal_stop_state (ecs->event_thread->suspend.stop_signal)))
6093 /* Notify observers the signal has "handle print" set. Note we
6094 returned early above if stopping; normal_stop handles the
6095 printing in that case. */
6096 if (signal_print[ecs->event_thread->suspend.stop_signal])
6098 /* The signal table tells us to print about this signal. */
6099 target_terminal::ours_for_output ();
6100 observer_notify_signal_received (ecs->event_thread->suspend.stop_signal);
6101 target_terminal::inferior ();
6104 /* Clear the signal if it should not be passed. */
6105 if (signal_program[ecs->event_thread->suspend.stop_signal] == 0)
6106 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
6108 if (ecs->event_thread->prev_pc == stop_pc
6109 && ecs->event_thread->control.trap_expected
6110 && ecs->event_thread->control.step_resume_breakpoint == NULL)
6112 /* We were just starting a new sequence, attempting to
6113 single-step off of a breakpoint and expecting a SIGTRAP.
6114 Instead this signal arrives. This signal will take us out
6115 of the stepping range so GDB needs to remember to, when
6116 the signal handler returns, resume stepping off that
6118 /* To simplify things, "continue" is forced to use the same
6119 code paths as single-step - set a breakpoint at the
6120 signal return address and then, once hit, step off that
6123 fprintf_unfiltered (gdb_stdlog,
6124 "infrun: signal arrived while stepping over "
6127 insert_hp_step_resume_breakpoint_at_frame (frame);
6128 ecs->event_thread->step_after_step_resume_breakpoint = 1;
6129 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6130 ecs->event_thread->control.trap_expected = 0;
6132 /* If we were nexting/stepping some other thread, switch to
6133 it, so that we don't continue it, losing control. */
6134 if (!switch_back_to_stepped_thread (ecs))
6139 if (ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_0
6140 && (pc_in_thread_step_range (stop_pc, ecs->event_thread)
6141 || ecs->event_thread->control.step_range_end == 1)
6142 && frame_id_eq (get_stack_frame_id (frame),
6143 ecs->event_thread->control.step_stack_frame_id)
6144 && ecs->event_thread->control.step_resume_breakpoint == NULL)
6146 /* The inferior is about to take a signal that will take it
6147 out of the single step range. Set a breakpoint at the
6148 current PC (which is presumably where the signal handler
6149 will eventually return) and then allow the inferior to
6152 Note that this is only needed for a signal delivered
6153 while in the single-step range. Nested signals aren't a
6154 problem as they eventually all return. */
6156 fprintf_unfiltered (gdb_stdlog,
6157 "infrun: signal may take us out of "
6158 "single-step range\n");
6160 clear_step_over_info ();
6161 insert_hp_step_resume_breakpoint_at_frame (frame);
6162 ecs->event_thread->step_after_step_resume_breakpoint = 1;
6163 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6164 ecs->event_thread->control.trap_expected = 0;
6169 /* Note: step_resume_breakpoint may be non-NULL. This occures
6170 when either there's a nested signal, or when there's a
6171 pending signal enabled just as the signal handler returns
6172 (leaving the inferior at the step-resume-breakpoint without
6173 actually executing it). Either way continue until the
6174 breakpoint is really hit. */
6176 if (!switch_back_to_stepped_thread (ecs))
6179 fprintf_unfiltered (gdb_stdlog,
6180 "infrun: random signal, keep going\n");
6187 process_event_stop_test (ecs);
6190 /* Come here when we've got some debug event / signal we can explain
6191 (IOW, not a random signal), and test whether it should cause a
6192 stop, or whether we should resume the inferior (transparently).
6193 E.g., could be a breakpoint whose condition evaluates false; we
6194 could be still stepping within the line; etc. */
6197 process_event_stop_test (struct execution_control_state *ecs)
6199 struct symtab_and_line stop_pc_sal;
6200 struct frame_info *frame;
6201 struct gdbarch *gdbarch;
6202 CORE_ADDR jmp_buf_pc;
6203 struct bpstat_what what;
6205 /* Handle cases caused by hitting a breakpoint. */
6207 frame = get_current_frame ();
6208 gdbarch = get_frame_arch (frame);
6210 what = bpstat_what (ecs->event_thread->control.stop_bpstat);
6212 if (what.call_dummy)
6214 stop_stack_dummy = what.call_dummy;
6217 /* A few breakpoint types have callbacks associated (e.g.,
6218 bp_jit_event). Run them now. */
6219 bpstat_run_callbacks (ecs->event_thread->control.stop_bpstat);
6221 /* If we hit an internal event that triggers symbol changes, the
6222 current frame will be invalidated within bpstat_what (e.g., if we
6223 hit an internal solib event). Re-fetch it. */
6224 frame = get_current_frame ();
6225 gdbarch = get_frame_arch (frame);
6227 switch (what.main_action)
6229 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
6230 /* If we hit the breakpoint at longjmp while stepping, we
6231 install a momentary breakpoint at the target of the
6235 fprintf_unfiltered (gdb_stdlog,
6236 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6238 ecs->event_thread->stepping_over_breakpoint = 1;
6240 if (what.is_longjmp)
6242 struct value *arg_value;
6244 /* If we set the longjmp breakpoint via a SystemTap probe,
6245 then use it to extract the arguments. The destination PC
6246 is the third argument to the probe. */
6247 arg_value = probe_safe_evaluate_at_pc (frame, 2);
6250 jmp_buf_pc = value_as_address (arg_value);
6251 jmp_buf_pc = gdbarch_addr_bits_remove (gdbarch, jmp_buf_pc);
6253 else if (!gdbarch_get_longjmp_target_p (gdbarch)
6254 || !gdbarch_get_longjmp_target (gdbarch,
6255 frame, &jmp_buf_pc))
6258 fprintf_unfiltered (gdb_stdlog,
6259 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6260 "(!gdbarch_get_longjmp_target)\n");
6265 /* Insert a breakpoint at resume address. */
6266 insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc);
6269 check_exception_resume (ecs, frame);
6273 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
6275 struct frame_info *init_frame;
6277 /* There are several cases to consider.
6279 1. The initiating frame no longer exists. In this case we
6280 must stop, because the exception or longjmp has gone too
6283 2. The initiating frame exists, and is the same as the
6284 current frame. We stop, because the exception or longjmp
6287 3. The initiating frame exists and is different from the
6288 current frame. This means the exception or longjmp has
6289 been caught beneath the initiating frame, so keep going.
6291 4. longjmp breakpoint has been placed just to protect
6292 against stale dummy frames and user is not interested in
6293 stopping around longjmps. */
6296 fprintf_unfiltered (gdb_stdlog,
6297 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6299 gdb_assert (ecs->event_thread->control.exception_resume_breakpoint
6301 delete_exception_resume_breakpoint (ecs->event_thread);
6303 if (what.is_longjmp)
6305 check_longjmp_breakpoint_for_call_dummy (ecs->event_thread);
6307 if (!frame_id_p (ecs->event_thread->initiating_frame))
6315 init_frame = frame_find_by_id (ecs->event_thread->initiating_frame);
6319 struct frame_id current_id
6320 = get_frame_id (get_current_frame ());
6321 if (frame_id_eq (current_id,
6322 ecs->event_thread->initiating_frame))
6324 /* Case 2. Fall through. */
6334 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6336 delete_step_resume_breakpoint (ecs->event_thread);
6338 end_stepping_range (ecs);
6342 case BPSTAT_WHAT_SINGLE:
6344 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
6345 ecs->event_thread->stepping_over_breakpoint = 1;
6346 /* Still need to check other stuff, at least the case where we
6347 are stepping and step out of the right range. */
6350 case BPSTAT_WHAT_STEP_RESUME:
6352 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6354 delete_step_resume_breakpoint (ecs->event_thread);
6355 if (ecs->event_thread->control.proceed_to_finish
6356 && execution_direction == EXEC_REVERSE)
6358 struct thread_info *tp = ecs->event_thread;
6360 /* We are finishing a function in reverse, and just hit the
6361 step-resume breakpoint at the start address of the
6362 function, and we're almost there -- just need to back up
6363 by one more single-step, which should take us back to the
6365 tp->control.step_range_start = tp->control.step_range_end = 1;
6369 fill_in_stop_func (gdbarch, ecs);
6370 if (stop_pc == ecs->stop_func_start
6371 && execution_direction == EXEC_REVERSE)
6373 /* We are stepping over a function call in reverse, and just
6374 hit the step-resume breakpoint at the start address of
6375 the function. Go back to single-stepping, which should
6376 take us back to the function call. */
6377 ecs->event_thread->stepping_over_breakpoint = 1;
6383 case BPSTAT_WHAT_STOP_NOISY:
6385 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6386 stop_print_frame = 1;
6388 /* Assume the thread stopped for a breapoint. We'll still check
6389 whether a/the breakpoint is there when the thread is next
6391 ecs->event_thread->stepping_over_breakpoint = 1;
6396 case BPSTAT_WHAT_STOP_SILENT:
6398 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6399 stop_print_frame = 0;
6401 /* Assume the thread stopped for a breapoint. We'll still check
6402 whether a/the breakpoint is there when the thread is next
6404 ecs->event_thread->stepping_over_breakpoint = 1;
6408 case BPSTAT_WHAT_HP_STEP_RESUME:
6410 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6412 delete_step_resume_breakpoint (ecs->event_thread);
6413 if (ecs->event_thread->step_after_step_resume_breakpoint)
6415 /* Back when the step-resume breakpoint was inserted, we
6416 were trying to single-step off a breakpoint. Go back to
6418 ecs->event_thread->step_after_step_resume_breakpoint = 0;
6419 ecs->event_thread->stepping_over_breakpoint = 1;
6425 case BPSTAT_WHAT_KEEP_CHECKING:
6429 /* If we stepped a permanent breakpoint and we had a high priority
6430 step-resume breakpoint for the address we stepped, but we didn't
6431 hit it, then we must have stepped into the signal handler. The
6432 step-resume was only necessary to catch the case of _not_
6433 stepping into the handler, so delete it, and fall through to
6434 checking whether the step finished. */
6435 if (ecs->event_thread->stepped_breakpoint)
6437 struct breakpoint *sr_bp
6438 = ecs->event_thread->control.step_resume_breakpoint;
6441 && sr_bp->loc->permanent
6442 && sr_bp->type == bp_hp_step_resume
6443 && sr_bp->loc->address == ecs->event_thread->prev_pc)
6446 fprintf_unfiltered (gdb_stdlog,
6447 "infrun: stepped permanent breakpoint, stopped in "
6449 delete_step_resume_breakpoint (ecs->event_thread);
6450 ecs->event_thread->step_after_step_resume_breakpoint = 0;
6454 /* We come here if we hit a breakpoint but should not stop for it.
6455 Possibly we also were stepping and should stop for that. So fall
6456 through and test for stepping. But, if not stepping, do not
6459 /* In all-stop mode, if we're currently stepping but have stopped in
6460 some other thread, we need to switch back to the stepped thread. */
6461 if (switch_back_to_stepped_thread (ecs))
6464 if (ecs->event_thread->control.step_resume_breakpoint)
6467 fprintf_unfiltered (gdb_stdlog,
6468 "infrun: step-resume breakpoint is inserted\n");
6470 /* Having a step-resume breakpoint overrides anything
6471 else having to do with stepping commands until
6472 that breakpoint is reached. */
6477 if (ecs->event_thread->control.step_range_end == 0)
6480 fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n");
6481 /* Likewise if we aren't even stepping. */
6486 /* Re-fetch current thread's frame in case the code above caused
6487 the frame cache to be re-initialized, making our FRAME variable
6488 a dangling pointer. */
6489 frame = get_current_frame ();
6490 gdbarch = get_frame_arch (frame);
6491 fill_in_stop_func (gdbarch, ecs);
6493 /* If stepping through a line, keep going if still within it.
6495 Note that step_range_end is the address of the first instruction
6496 beyond the step range, and NOT the address of the last instruction
6499 Note also that during reverse execution, we may be stepping
6500 through a function epilogue and therefore must detect when
6501 the current-frame changes in the middle of a line. */
6503 if (pc_in_thread_step_range (stop_pc, ecs->event_thread)
6504 && (execution_direction != EXEC_REVERSE
6505 || frame_id_eq (get_frame_id (frame),
6506 ecs->event_thread->control.step_frame_id)))
6510 (gdb_stdlog, "infrun: stepping inside range [%s-%s]\n",
6511 paddress (gdbarch, ecs->event_thread->control.step_range_start),
6512 paddress (gdbarch, ecs->event_thread->control.step_range_end));
6514 /* Tentatively re-enable range stepping; `resume' disables it if
6515 necessary (e.g., if we're stepping over a breakpoint or we
6516 have software watchpoints). */
6517 ecs->event_thread->control.may_range_step = 1;
6519 /* When stepping backward, stop at beginning of line range
6520 (unless it's the function entry point, in which case
6521 keep going back to the call point). */
6522 if (stop_pc == ecs->event_thread->control.step_range_start
6523 && stop_pc != ecs->stop_func_start
6524 && execution_direction == EXEC_REVERSE)
6525 end_stepping_range (ecs);
6532 /* We stepped out of the stepping range. */
6534 /* If we are stepping at the source level and entered the runtime
6535 loader dynamic symbol resolution code...
6537 EXEC_FORWARD: we keep on single stepping until we exit the run
6538 time loader code and reach the callee's address.
6540 EXEC_REVERSE: we've already executed the callee (backward), and
6541 the runtime loader code is handled just like any other
6542 undebuggable function call. Now we need only keep stepping
6543 backward through the trampoline code, and that's handled further
6544 down, so there is nothing for us to do here. */
6546 if (execution_direction != EXEC_REVERSE
6547 && ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6548 && in_solib_dynsym_resolve_code (stop_pc))
6550 CORE_ADDR pc_after_resolver =
6551 gdbarch_skip_solib_resolver (gdbarch, stop_pc);
6554 fprintf_unfiltered (gdb_stdlog,
6555 "infrun: stepped into dynsym resolve code\n");
6557 if (pc_after_resolver)
6559 /* Set up a step-resume breakpoint at the address
6560 indicated by SKIP_SOLIB_RESOLVER. */
6561 symtab_and_line sr_sal;
6562 sr_sal.pc = pc_after_resolver;
6563 sr_sal.pspace = get_frame_program_space (frame);
6565 insert_step_resume_breakpoint_at_sal (gdbarch,
6566 sr_sal, null_frame_id);
6573 if (ecs->event_thread->control.step_range_end != 1
6574 && (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6575 || ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
6576 && get_frame_type (frame) == SIGTRAMP_FRAME)
6579 fprintf_unfiltered (gdb_stdlog,
6580 "infrun: stepped into signal trampoline\n");
6581 /* The inferior, while doing a "step" or "next", has ended up in
6582 a signal trampoline (either by a signal being delivered or by
6583 the signal handler returning). Just single-step until the
6584 inferior leaves the trampoline (either by calling the handler
6590 /* If we're in the return path from a shared library trampoline,
6591 we want to proceed through the trampoline when stepping. */
6592 /* macro/2012-04-25: This needs to come before the subroutine
6593 call check below as on some targets return trampolines look
6594 like subroutine calls (MIPS16 return thunks). */
6595 if (gdbarch_in_solib_return_trampoline (gdbarch,
6596 stop_pc, ecs->stop_func_name)
6597 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
6599 /* Determine where this trampoline returns. */
6600 CORE_ADDR real_stop_pc;
6602 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
6605 fprintf_unfiltered (gdb_stdlog,
6606 "infrun: stepped into solib return tramp\n");
6608 /* Only proceed through if we know where it's going. */
6611 /* And put the step-breakpoint there and go until there. */
6612 symtab_and_line sr_sal;
6613 sr_sal.pc = real_stop_pc;
6614 sr_sal.section = find_pc_overlay (sr_sal.pc);
6615 sr_sal.pspace = get_frame_program_space (frame);
6617 /* Do not specify what the fp should be when we stop since
6618 on some machines the prologue is where the new fp value
6620 insert_step_resume_breakpoint_at_sal (gdbarch,
6621 sr_sal, null_frame_id);
6623 /* Restart without fiddling with the step ranges or
6630 /* Check for subroutine calls. The check for the current frame
6631 equalling the step ID is not necessary - the check of the
6632 previous frame's ID is sufficient - but it is a common case and
6633 cheaper than checking the previous frame's ID.
6635 NOTE: frame_id_eq will never report two invalid frame IDs as
6636 being equal, so to get into this block, both the current and
6637 previous frame must have valid frame IDs. */
6638 /* The outer_frame_id check is a heuristic to detect stepping
6639 through startup code. If we step over an instruction which
6640 sets the stack pointer from an invalid value to a valid value,
6641 we may detect that as a subroutine call from the mythical
6642 "outermost" function. This could be fixed by marking
6643 outermost frames as !stack_p,code_p,special_p. Then the
6644 initial outermost frame, before sp was valid, would
6645 have code_addr == &_start. See the comment in frame_id_eq
6647 if (!frame_id_eq (get_stack_frame_id (frame),
6648 ecs->event_thread->control.step_stack_frame_id)
6649 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6650 ecs->event_thread->control.step_stack_frame_id)
6651 && (!frame_id_eq (ecs->event_thread->control.step_stack_frame_id,
6653 || (ecs->event_thread->control.step_start_function
6654 != find_pc_function (stop_pc)))))
6656 CORE_ADDR real_stop_pc;
6659 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n");
6661 if (ecs->event_thread->control.step_over_calls == STEP_OVER_NONE)
6663 /* I presume that step_over_calls is only 0 when we're
6664 supposed to be stepping at the assembly language level
6665 ("stepi"). Just stop. */
6666 /* And this works the same backward as frontward. MVS */
6667 end_stepping_range (ecs);
6671 /* Reverse stepping through solib trampolines. */
6673 if (execution_direction == EXEC_REVERSE
6674 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE
6675 && (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
6676 || (ecs->stop_func_start == 0
6677 && in_solib_dynsym_resolve_code (stop_pc))))
6679 /* Any solib trampoline code can be handled in reverse
6680 by simply continuing to single-step. We have already
6681 executed the solib function (backwards), and a few
6682 steps will take us back through the trampoline to the
6688 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
6690 /* We're doing a "next".
6692 Normal (forward) execution: set a breakpoint at the
6693 callee's return address (the address at which the caller
6696 Reverse (backward) execution. set the step-resume
6697 breakpoint at the start of the function that we just
6698 stepped into (backwards), and continue to there. When we
6699 get there, we'll need to single-step back to the caller. */
6701 if (execution_direction == EXEC_REVERSE)
6703 /* If we're already at the start of the function, we've either
6704 just stepped backward into a single instruction function,
6705 or stepped back out of a signal handler to the first instruction
6706 of the function. Just keep going, which will single-step back
6708 if (ecs->stop_func_start != stop_pc && ecs->stop_func_start != 0)
6710 /* Normal function call return (static or dynamic). */
6711 symtab_and_line sr_sal;
6712 sr_sal.pc = ecs->stop_func_start;
6713 sr_sal.pspace = get_frame_program_space (frame);
6714 insert_step_resume_breakpoint_at_sal (gdbarch,
6715 sr_sal, null_frame_id);
6719 insert_step_resume_breakpoint_at_caller (frame);
6725 /* If we are in a function call trampoline (a stub between the
6726 calling routine and the real function), locate the real
6727 function. That's what tells us (a) whether we want to step
6728 into it at all, and (b) what prologue we want to run to the
6729 end of, if we do step into it. */
6730 real_stop_pc = skip_language_trampoline (frame, stop_pc);
6731 if (real_stop_pc == 0)
6732 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
6733 if (real_stop_pc != 0)
6734 ecs->stop_func_start = real_stop_pc;
6736 if (real_stop_pc != 0 && in_solib_dynsym_resolve_code (real_stop_pc))
6738 symtab_and_line sr_sal;
6739 sr_sal.pc = ecs->stop_func_start;
6740 sr_sal.pspace = get_frame_program_space (frame);
6742 insert_step_resume_breakpoint_at_sal (gdbarch,
6743 sr_sal, null_frame_id);
6748 /* If we have line number information for the function we are
6749 thinking of stepping into and the function isn't on the skip
6752 If there are several symtabs at that PC (e.g. with include
6753 files), just want to know whether *any* of them have line
6754 numbers. find_pc_line handles this. */
6756 struct symtab_and_line tmp_sal;
6758 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
6759 if (tmp_sal.line != 0
6760 && !function_name_is_marked_for_skip (ecs->stop_func_name,
6763 if (execution_direction == EXEC_REVERSE)
6764 handle_step_into_function_backward (gdbarch, ecs);
6766 handle_step_into_function (gdbarch, ecs);
6771 /* If we have no line number and the step-stop-if-no-debug is
6772 set, we stop the step so that the user has a chance to switch
6773 in assembly mode. */
6774 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6775 && step_stop_if_no_debug)
6777 end_stepping_range (ecs);
6781 if (execution_direction == EXEC_REVERSE)
6783 /* If we're already at the start of the function, we've either just
6784 stepped backward into a single instruction function without line
6785 number info, or stepped back out of a signal handler to the first
6786 instruction of the function without line number info. Just keep
6787 going, which will single-step back to the caller. */
6788 if (ecs->stop_func_start != stop_pc)
6790 /* Set a breakpoint at callee's start address.
6791 From there we can step once and be back in the caller. */
6792 symtab_and_line sr_sal;
6793 sr_sal.pc = ecs->stop_func_start;
6794 sr_sal.pspace = get_frame_program_space (frame);
6795 insert_step_resume_breakpoint_at_sal (gdbarch,
6796 sr_sal, null_frame_id);
6800 /* Set a breakpoint at callee's return address (the address
6801 at which the caller will resume). */
6802 insert_step_resume_breakpoint_at_caller (frame);
6808 /* Reverse stepping through solib trampolines. */
6810 if (execution_direction == EXEC_REVERSE
6811 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
6813 if (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
6814 || (ecs->stop_func_start == 0
6815 && in_solib_dynsym_resolve_code (stop_pc)))
6817 /* Any solib trampoline code can be handled in reverse
6818 by simply continuing to single-step. We have already
6819 executed the solib function (backwards), and a few
6820 steps will take us back through the trampoline to the
6825 else if (in_solib_dynsym_resolve_code (stop_pc))
6827 /* Stepped backward into the solib dynsym resolver.
6828 Set a breakpoint at its start and continue, then
6829 one more step will take us out. */
6830 symtab_and_line sr_sal;
6831 sr_sal.pc = ecs->stop_func_start;
6832 sr_sal.pspace = get_frame_program_space (frame);
6833 insert_step_resume_breakpoint_at_sal (gdbarch,
6834 sr_sal, null_frame_id);
6840 stop_pc_sal = find_pc_line (stop_pc, 0);
6842 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6843 the trampoline processing logic, however, there are some trampolines
6844 that have no names, so we should do trampoline handling first. */
6845 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6846 && ecs->stop_func_name == NULL
6847 && stop_pc_sal.line == 0)
6850 fprintf_unfiltered (gdb_stdlog,
6851 "infrun: stepped into undebuggable function\n");
6853 /* The inferior just stepped into, or returned to, an
6854 undebuggable function (where there is no debugging information
6855 and no line number corresponding to the address where the
6856 inferior stopped). Since we want to skip this kind of code,
6857 we keep going until the inferior returns from this
6858 function - unless the user has asked us not to (via
6859 set step-mode) or we no longer know how to get back
6860 to the call site. */
6861 if (step_stop_if_no_debug
6862 || !frame_id_p (frame_unwind_caller_id (frame)))
6864 /* If we have no line number and the step-stop-if-no-debug
6865 is set, we stop the step so that the user has a chance to
6866 switch in assembly mode. */
6867 end_stepping_range (ecs);
6872 /* Set a breakpoint at callee's return address (the address
6873 at which the caller will resume). */
6874 insert_step_resume_breakpoint_at_caller (frame);
6880 if (ecs->event_thread->control.step_range_end == 1)
6882 /* It is stepi or nexti. We always want to stop stepping after
6885 fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
6886 end_stepping_range (ecs);
6890 if (stop_pc_sal.line == 0)
6892 /* We have no line number information. That means to stop
6893 stepping (does this always happen right after one instruction,
6894 when we do "s" in a function with no line numbers,
6895 or can this happen as a result of a return or longjmp?). */
6897 fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n");
6898 end_stepping_range (ecs);
6902 /* Look for "calls" to inlined functions, part one. If the inline
6903 frame machinery detected some skipped call sites, we have entered
6904 a new inline function. */
6906 if (frame_id_eq (get_frame_id (get_current_frame ()),
6907 ecs->event_thread->control.step_frame_id)
6908 && inline_skipped_frames (ecs->ptid))
6911 fprintf_unfiltered (gdb_stdlog,
6912 "infrun: stepped into inlined function\n");
6914 symtab_and_line call_sal = find_frame_sal (get_current_frame ());
6916 if (ecs->event_thread->control.step_over_calls != STEP_OVER_ALL)
6918 /* For "step", we're going to stop. But if the call site
6919 for this inlined function is on the same source line as
6920 we were previously stepping, go down into the function
6921 first. Otherwise stop at the call site. */
6923 if (call_sal.line == ecs->event_thread->current_line
6924 && call_sal.symtab == ecs->event_thread->current_symtab)
6925 step_into_inline_frame (ecs->ptid);
6927 end_stepping_range (ecs);
6932 /* For "next", we should stop at the call site if it is on a
6933 different source line. Otherwise continue through the
6934 inlined function. */
6935 if (call_sal.line == ecs->event_thread->current_line
6936 && call_sal.symtab == ecs->event_thread->current_symtab)
6939 end_stepping_range (ecs);
6944 /* Look for "calls" to inlined functions, part two. If we are still
6945 in the same real function we were stepping through, but we have
6946 to go further up to find the exact frame ID, we are stepping
6947 through a more inlined call beyond its call site. */
6949 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6950 && !frame_id_eq (get_frame_id (get_current_frame ()),
6951 ecs->event_thread->control.step_frame_id)
6952 && stepped_in_from (get_current_frame (),
6953 ecs->event_thread->control.step_frame_id))
6956 fprintf_unfiltered (gdb_stdlog,
6957 "infrun: stepping through inlined function\n");
6959 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
6962 end_stepping_range (ecs);
6966 if ((stop_pc == stop_pc_sal.pc)
6967 && (ecs->event_thread->current_line != stop_pc_sal.line
6968 || ecs->event_thread->current_symtab != stop_pc_sal.symtab))
6970 /* We are at the start of a different line. So stop. Note that
6971 we don't stop if we step into the middle of a different line.
6972 That is said to make things like for (;;) statements work
6975 fprintf_unfiltered (gdb_stdlog,
6976 "infrun: stepped to a different line\n");
6977 end_stepping_range (ecs);
6981 /* We aren't done stepping.
6983 Optimize by setting the stepping range to the line.
6984 (We might not be in the original line, but if we entered a
6985 new line in mid-statement, we continue stepping. This makes
6986 things like for(;;) statements work better.) */
6988 ecs->event_thread->control.step_range_start = stop_pc_sal.pc;
6989 ecs->event_thread->control.step_range_end = stop_pc_sal.end;
6990 ecs->event_thread->control.may_range_step = 1;
6991 set_step_info (frame, stop_pc_sal);
6994 fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n");
6998 /* In all-stop mode, if we're currently stepping but have stopped in
6999 some other thread, we may need to switch back to the stepped
7000 thread. Returns true we set the inferior running, false if we left
7001 it stopped (and the event needs further processing). */
7004 switch_back_to_stepped_thread (struct execution_control_state *ecs)
7006 if (!target_is_non_stop_p ())
7008 struct thread_info *tp;
7009 struct thread_info *stepping_thread;
7011 /* If any thread is blocked on some internal breakpoint, and we
7012 simply need to step over that breakpoint to get it going
7013 again, do that first. */
7015 /* However, if we see an event for the stepping thread, then we
7016 know all other threads have been moved past their breakpoints
7017 already. Let the caller check whether the step is finished,
7018 etc., before deciding to move it past a breakpoint. */
7019 if (ecs->event_thread->control.step_range_end != 0)
7022 /* Check if the current thread is blocked on an incomplete
7023 step-over, interrupted by a random signal. */
7024 if (ecs->event_thread->control.trap_expected
7025 && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_TRAP)
7029 fprintf_unfiltered (gdb_stdlog,
7030 "infrun: need to finish step-over of [%s]\n",
7031 target_pid_to_str (ecs->event_thread->ptid));
7037 /* Check if the current thread is blocked by a single-step
7038 breakpoint of another thread. */
7039 if (ecs->hit_singlestep_breakpoint)
7043 fprintf_unfiltered (gdb_stdlog,
7044 "infrun: need to step [%s] over single-step "
7046 target_pid_to_str (ecs->ptid));
7052 /* If this thread needs yet another step-over (e.g., stepping
7053 through a delay slot), do it first before moving on to
7055 if (thread_still_needs_step_over (ecs->event_thread))
7059 fprintf_unfiltered (gdb_stdlog,
7060 "infrun: thread [%s] still needs step-over\n",
7061 target_pid_to_str (ecs->event_thread->ptid));
7067 /* If scheduler locking applies even if not stepping, there's no
7068 need to walk over threads. Above we've checked whether the
7069 current thread is stepping. If some other thread not the
7070 event thread is stepping, then it must be that scheduler
7071 locking is not in effect. */
7072 if (schedlock_applies (ecs->event_thread))
7075 /* Otherwise, we no longer expect a trap in the current thread.
7076 Clear the trap_expected flag before switching back -- this is
7077 what keep_going does as well, if we call it. */
7078 ecs->event_thread->control.trap_expected = 0;
7080 /* Likewise, clear the signal if it should not be passed. */
7081 if (!signal_program[ecs->event_thread->suspend.stop_signal])
7082 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
7084 /* Do all pending step-overs before actually proceeding with
7086 if (start_step_over ())
7088 prepare_to_wait (ecs);
7092 /* Look for the stepping/nexting thread. */
7093 stepping_thread = NULL;
7095 ALL_NON_EXITED_THREADS (tp)
7097 /* Ignore threads of processes the caller is not
7100 && ptid_get_pid (tp->ptid) != ptid_get_pid (ecs->ptid))
7103 /* When stepping over a breakpoint, we lock all threads
7104 except the one that needs to move past the breakpoint.
7105 If a non-event thread has this set, the "incomplete
7106 step-over" check above should have caught it earlier. */
7107 if (tp->control.trap_expected)
7109 internal_error (__FILE__, __LINE__,
7110 "[%s] has inconsistent state: "
7111 "trap_expected=%d\n",
7112 target_pid_to_str (tp->ptid),
7113 tp->control.trap_expected);
7116 /* Did we find the stepping thread? */
7117 if (tp->control.step_range_end)
7119 /* Yep. There should only one though. */
7120 gdb_assert (stepping_thread == NULL);
7122 /* The event thread is handled at the top, before we
7124 gdb_assert (tp != ecs->event_thread);
7126 /* If some thread other than the event thread is
7127 stepping, then scheduler locking can't be in effect,
7128 otherwise we wouldn't have resumed the current event
7129 thread in the first place. */
7130 gdb_assert (!schedlock_applies (tp));
7132 stepping_thread = tp;
7136 if (stepping_thread != NULL)
7139 fprintf_unfiltered (gdb_stdlog,
7140 "infrun: switching back to stepped thread\n");
7142 if (keep_going_stepped_thread (stepping_thread))
7144 prepare_to_wait (ecs);
7153 /* Set a previously stepped thread back to stepping. Returns true on
7154 success, false if the resume is not possible (e.g., the thread
7158 keep_going_stepped_thread (struct thread_info *tp)
7160 struct frame_info *frame;
7161 struct execution_control_state ecss;
7162 struct execution_control_state *ecs = &ecss;
7164 /* If the stepping thread exited, then don't try to switch back and
7165 resume it, which could fail in several different ways depending
7166 on the target. Instead, just keep going.
7168 We can find a stepping dead thread in the thread list in two
7171 - The target supports thread exit events, and when the target
7172 tries to delete the thread from the thread list, inferior_ptid
7173 pointed at the exiting thread. In such case, calling
7174 delete_thread does not really remove the thread from the list;
7175 instead, the thread is left listed, with 'exited' state.
7177 - The target's debug interface does not support thread exit
7178 events, and so we have no idea whatsoever if the previously
7179 stepping thread is still alive. For that reason, we need to
7180 synchronously query the target now. */
7182 if (is_exited (tp->ptid)
7183 || !target_thread_alive (tp->ptid))
7186 fprintf_unfiltered (gdb_stdlog,
7187 "infrun: not resuming previously "
7188 "stepped thread, it has vanished\n");
7190 delete_thread (tp->ptid);
7195 fprintf_unfiltered (gdb_stdlog,
7196 "infrun: resuming previously stepped thread\n");
7198 reset_ecs (ecs, tp);
7199 switch_to_thread (tp->ptid);
7201 stop_pc = regcache_read_pc (get_thread_regcache (tp->ptid));
7202 frame = get_current_frame ();
7204 /* If the PC of the thread we were trying to single-step has
7205 changed, then that thread has trapped or been signaled, but the
7206 event has not been reported to GDB yet. Re-poll the target
7207 looking for this particular thread's event (i.e. temporarily
7208 enable schedlock) by:
7210 - setting a break at the current PC
7211 - resuming that particular thread, only (by setting trap
7214 This prevents us continuously moving the single-step breakpoint
7215 forward, one instruction at a time, overstepping. */
7217 if (stop_pc != tp->prev_pc)
7222 fprintf_unfiltered (gdb_stdlog,
7223 "infrun: expected thread advanced also (%s -> %s)\n",
7224 paddress (target_gdbarch (), tp->prev_pc),
7225 paddress (target_gdbarch (), stop_pc));
7227 /* Clear the info of the previous step-over, as it's no longer
7228 valid (if the thread was trying to step over a breakpoint, it
7229 has already succeeded). It's what keep_going would do too,
7230 if we called it. Do this before trying to insert the sss
7231 breakpoint, otherwise if we were previously trying to step
7232 over this exact address in another thread, the breakpoint is
7234 clear_step_over_info ();
7235 tp->control.trap_expected = 0;
7237 insert_single_step_breakpoint (get_frame_arch (frame),
7238 get_frame_address_space (frame),
7242 resume_ptid = internal_resume_ptid (tp->control.stepping_command);
7243 do_target_resume (resume_ptid, 0, GDB_SIGNAL_0);
7248 fprintf_unfiltered (gdb_stdlog,
7249 "infrun: expected thread still hasn't advanced\n");
7251 keep_going_pass_signal (ecs);
7256 /* Is thread TP in the middle of (software or hardware)
7257 single-stepping? (Note the result of this function must never be
7258 passed directly as target_resume's STEP parameter.) */
7261 currently_stepping (struct thread_info *tp)
7263 return ((tp->control.step_range_end
7264 && tp->control.step_resume_breakpoint == NULL)
7265 || tp->control.trap_expected
7266 || tp->stepped_breakpoint
7267 || bpstat_should_step ());
7270 /* Inferior has stepped into a subroutine call with source code that
7271 we should not step over. Do step to the first line of code in
7275 handle_step_into_function (struct gdbarch *gdbarch,
7276 struct execution_control_state *ecs)
7278 fill_in_stop_func (gdbarch, ecs);
7280 compunit_symtab *cust = find_pc_compunit_symtab (stop_pc);
7281 if (cust != NULL && compunit_language (cust) != language_asm)
7282 ecs->stop_func_start
7283 = gdbarch_skip_prologue_noexcept (gdbarch, ecs->stop_func_start);
7285 symtab_and_line stop_func_sal = find_pc_line (ecs->stop_func_start, 0);
7286 /* Use the step_resume_break to step until the end of the prologue,
7287 even if that involves jumps (as it seems to on the vax under
7289 /* If the prologue ends in the middle of a source line, continue to
7290 the end of that source line (if it is still within the function).
7291 Otherwise, just go to end of prologue. */
7292 if (stop_func_sal.end
7293 && stop_func_sal.pc != ecs->stop_func_start
7294 && stop_func_sal.end < ecs->stop_func_end)
7295 ecs->stop_func_start = stop_func_sal.end;
7297 /* Architectures which require breakpoint adjustment might not be able
7298 to place a breakpoint at the computed address. If so, the test
7299 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7300 ecs->stop_func_start to an address at which a breakpoint may be
7301 legitimately placed.
7303 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7304 made, GDB will enter an infinite loop when stepping through
7305 optimized code consisting of VLIW instructions which contain
7306 subinstructions corresponding to different source lines. On
7307 FR-V, it's not permitted to place a breakpoint on any but the
7308 first subinstruction of a VLIW instruction. When a breakpoint is
7309 set, GDB will adjust the breakpoint address to the beginning of
7310 the VLIW instruction. Thus, we need to make the corresponding
7311 adjustment here when computing the stop address. */
7313 if (gdbarch_adjust_breakpoint_address_p (gdbarch))
7315 ecs->stop_func_start
7316 = gdbarch_adjust_breakpoint_address (gdbarch,
7317 ecs->stop_func_start);
7320 if (ecs->stop_func_start == stop_pc)
7322 /* We are already there: stop now. */
7323 end_stepping_range (ecs);
7328 /* Put the step-breakpoint there and go until there. */
7329 symtab_and_line sr_sal;
7330 sr_sal.pc = ecs->stop_func_start;
7331 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
7332 sr_sal.pspace = get_frame_program_space (get_current_frame ());
7334 /* Do not specify what the fp should be when we stop since on
7335 some machines the prologue is where the new fp value is
7337 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal, null_frame_id);
7339 /* And make sure stepping stops right away then. */
7340 ecs->event_thread->control.step_range_end
7341 = ecs->event_thread->control.step_range_start;
7346 /* Inferior has stepped backward into a subroutine call with source
7347 code that we should not step over. Do step to the beginning of the
7348 last line of code in it. */
7351 handle_step_into_function_backward (struct gdbarch *gdbarch,
7352 struct execution_control_state *ecs)
7354 struct compunit_symtab *cust;
7355 struct symtab_and_line stop_func_sal;
7357 fill_in_stop_func (gdbarch, ecs);
7359 cust = find_pc_compunit_symtab (stop_pc);
7360 if (cust != NULL && compunit_language (cust) != language_asm)
7361 ecs->stop_func_start
7362 = gdbarch_skip_prologue_noexcept (gdbarch, ecs->stop_func_start);
7364 stop_func_sal = find_pc_line (stop_pc, 0);
7366 /* OK, we're just going to keep stepping here. */
7367 if (stop_func_sal.pc == stop_pc)
7369 /* We're there already. Just stop stepping now. */
7370 end_stepping_range (ecs);
7374 /* Else just reset the step range and keep going.
7375 No step-resume breakpoint, they don't work for
7376 epilogues, which can have multiple entry paths. */
7377 ecs->event_thread->control.step_range_start = stop_func_sal.pc;
7378 ecs->event_thread->control.step_range_end = stop_func_sal.end;
7384 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7385 This is used to both functions and to skip over code. */
7388 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch *gdbarch,
7389 struct symtab_and_line sr_sal,
7390 struct frame_id sr_id,
7391 enum bptype sr_type)
7393 /* There should never be more than one step-resume or longjmp-resume
7394 breakpoint per thread, so we should never be setting a new
7395 step_resume_breakpoint when one is already active. */
7396 gdb_assert (inferior_thread ()->control.step_resume_breakpoint == NULL);
7397 gdb_assert (sr_type == bp_step_resume || sr_type == bp_hp_step_resume);
7400 fprintf_unfiltered (gdb_stdlog,
7401 "infrun: inserting step-resume breakpoint at %s\n",
7402 paddress (gdbarch, sr_sal.pc));
7404 inferior_thread ()->control.step_resume_breakpoint
7405 = set_momentary_breakpoint (gdbarch, sr_sal, sr_id, sr_type);
7409 insert_step_resume_breakpoint_at_sal (struct gdbarch *gdbarch,
7410 struct symtab_and_line sr_sal,
7411 struct frame_id sr_id)
7413 insert_step_resume_breakpoint_at_sal_1 (gdbarch,
7418 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7419 This is used to skip a potential signal handler.
7421 This is called with the interrupted function's frame. The signal
7422 handler, when it returns, will resume the interrupted function at
7426 insert_hp_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
7428 gdb_assert (return_frame != NULL);
7430 struct gdbarch *gdbarch = get_frame_arch (return_frame);
7432 symtab_and_line sr_sal;
7433 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch, get_frame_pc (return_frame));
7434 sr_sal.section = find_pc_overlay (sr_sal.pc);
7435 sr_sal.pspace = get_frame_program_space (return_frame);
7437 insert_step_resume_breakpoint_at_sal_1 (gdbarch, sr_sal,
7438 get_stack_frame_id (return_frame),
7442 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7443 is used to skip a function after stepping into it (for "next" or if
7444 the called function has no debugging information).
7446 The current function has almost always been reached by single
7447 stepping a call or return instruction. NEXT_FRAME belongs to the
7448 current function, and the breakpoint will be set at the caller's
7451 This is a separate function rather than reusing
7452 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7453 get_prev_frame, which may stop prematurely (see the implementation
7454 of frame_unwind_caller_id for an example). */
7457 insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame)
7459 /* We shouldn't have gotten here if we don't know where the call site
7461 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame)));
7463 struct gdbarch *gdbarch = frame_unwind_caller_arch (next_frame);
7465 symtab_and_line sr_sal;
7466 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch,
7467 frame_unwind_caller_pc (next_frame));
7468 sr_sal.section = find_pc_overlay (sr_sal.pc);
7469 sr_sal.pspace = frame_unwind_program_space (next_frame);
7471 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal,
7472 frame_unwind_caller_id (next_frame));
7475 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7476 new breakpoint at the target of a jmp_buf. The handling of
7477 longjmp-resume uses the same mechanisms used for handling
7478 "step-resume" breakpoints. */
7481 insert_longjmp_resume_breakpoint (struct gdbarch *gdbarch, CORE_ADDR pc)
7483 /* There should never be more than one longjmp-resume breakpoint per
7484 thread, so we should never be setting a new
7485 longjmp_resume_breakpoint when one is already active. */
7486 gdb_assert (inferior_thread ()->control.exception_resume_breakpoint == NULL);
7489 fprintf_unfiltered (gdb_stdlog,
7490 "infrun: inserting longjmp-resume breakpoint at %s\n",
7491 paddress (gdbarch, pc));
7493 inferior_thread ()->control.exception_resume_breakpoint =
7494 set_momentary_breakpoint_at_pc (gdbarch, pc, bp_longjmp_resume);
7497 /* Insert an exception resume breakpoint. TP is the thread throwing
7498 the exception. The block B is the block of the unwinder debug hook
7499 function. FRAME is the frame corresponding to the call to this
7500 function. SYM is the symbol of the function argument holding the
7501 target PC of the exception. */
7504 insert_exception_resume_breakpoint (struct thread_info *tp,
7505 const struct block *b,
7506 struct frame_info *frame,
7511 struct block_symbol vsym;
7512 struct value *value;
7514 struct breakpoint *bp;
7516 vsym = lookup_symbol (SYMBOL_LINKAGE_NAME (sym), b, VAR_DOMAIN, NULL);
7517 value = read_var_value (vsym.symbol, vsym.block, frame);
7518 /* If the value was optimized out, revert to the old behavior. */
7519 if (! value_optimized_out (value))
7521 handler = value_as_address (value);
7524 fprintf_unfiltered (gdb_stdlog,
7525 "infrun: exception resume at %lx\n",
7526 (unsigned long) handler);
7528 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
7529 handler, bp_exception_resume);
7531 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7534 bp->thread = tp->global_num;
7535 inferior_thread ()->control.exception_resume_breakpoint = bp;
7538 CATCH (e, RETURN_MASK_ERROR)
7540 /* We want to ignore errors here. */
7545 /* A helper for check_exception_resume that sets an
7546 exception-breakpoint based on a SystemTap probe. */
7549 insert_exception_resume_from_probe (struct thread_info *tp,
7550 const struct bound_probe *probe,
7551 struct frame_info *frame)
7553 struct value *arg_value;
7555 struct breakpoint *bp;
7557 arg_value = probe_safe_evaluate_at_pc (frame, 1);
7561 handler = value_as_address (arg_value);
7564 fprintf_unfiltered (gdb_stdlog,
7565 "infrun: exception resume at %s\n",
7566 paddress (get_objfile_arch (probe->objfile),
7569 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
7570 handler, bp_exception_resume);
7571 bp->thread = tp->global_num;
7572 inferior_thread ()->control.exception_resume_breakpoint = bp;
7575 /* This is called when an exception has been intercepted. Check to
7576 see whether the exception's destination is of interest, and if so,
7577 set an exception resume breakpoint there. */
7580 check_exception_resume (struct execution_control_state *ecs,
7581 struct frame_info *frame)
7583 struct bound_probe probe;
7584 struct symbol *func;
7586 /* First see if this exception unwinding breakpoint was set via a
7587 SystemTap probe point. If so, the probe has two arguments: the
7588 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7589 set a breakpoint there. */
7590 probe = find_probe_by_pc (get_frame_pc (frame));
7593 insert_exception_resume_from_probe (ecs->event_thread, &probe, frame);
7597 func = get_frame_function (frame);
7603 const struct block *b;
7604 struct block_iterator iter;
7608 /* The exception breakpoint is a thread-specific breakpoint on
7609 the unwinder's debug hook, declared as:
7611 void _Unwind_DebugHook (void *cfa, void *handler);
7613 The CFA argument indicates the frame to which control is
7614 about to be transferred. HANDLER is the destination PC.
7616 We ignore the CFA and set a temporary breakpoint at HANDLER.
7617 This is not extremely efficient but it avoids issues in gdb
7618 with computing the DWARF CFA, and it also works even in weird
7619 cases such as throwing an exception from inside a signal
7622 b = SYMBOL_BLOCK_VALUE (func);
7623 ALL_BLOCK_SYMBOLS (b, iter, sym)
7625 if (!SYMBOL_IS_ARGUMENT (sym))
7632 insert_exception_resume_breakpoint (ecs->event_thread,
7638 CATCH (e, RETURN_MASK_ERROR)
7645 stop_waiting (struct execution_control_state *ecs)
7648 fprintf_unfiltered (gdb_stdlog, "infrun: stop_waiting\n");
7650 /* Let callers know we don't want to wait for the inferior anymore. */
7651 ecs->wait_some_more = 0;
7653 /* If all-stop, but the target is always in non-stop mode, stop all
7654 threads now that we're presenting the stop to the user. */
7655 if (!non_stop && target_is_non_stop_p ())
7656 stop_all_threads ();
7659 /* Like keep_going, but passes the signal to the inferior, even if the
7660 signal is set to nopass. */
7663 keep_going_pass_signal (struct execution_control_state *ecs)
7665 /* Make sure normal_stop is called if we get a QUIT handled before
7667 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
7669 gdb_assert (ptid_equal (ecs->event_thread->ptid, inferior_ptid));
7670 gdb_assert (!ecs->event_thread->resumed);
7672 /* Save the pc before execution, to compare with pc after stop. */
7673 ecs->event_thread->prev_pc
7674 = regcache_read_pc (get_thread_regcache (ecs->ptid));
7676 if (ecs->event_thread->control.trap_expected)
7678 struct thread_info *tp = ecs->event_thread;
7681 fprintf_unfiltered (gdb_stdlog,
7682 "infrun: %s has trap_expected set, "
7683 "resuming to collect trap\n",
7684 target_pid_to_str (tp->ptid));
7686 /* We haven't yet gotten our trap, and either: intercepted a
7687 non-signal event (e.g., a fork); or took a signal which we
7688 are supposed to pass through to the inferior. Simply
7690 discard_cleanups (old_cleanups);
7691 resume (ecs->event_thread->suspend.stop_signal);
7693 else if (step_over_info_valid_p ())
7695 /* Another thread is stepping over a breakpoint in-line. If
7696 this thread needs a step-over too, queue the request. In
7697 either case, this resume must be deferred for later. */
7698 struct thread_info *tp = ecs->event_thread;
7700 if (ecs->hit_singlestep_breakpoint
7701 || thread_still_needs_step_over (tp))
7704 fprintf_unfiltered (gdb_stdlog,
7705 "infrun: step-over already in progress: "
7706 "step-over for %s deferred\n",
7707 target_pid_to_str (tp->ptid));
7708 thread_step_over_chain_enqueue (tp);
7713 fprintf_unfiltered (gdb_stdlog,
7714 "infrun: step-over in progress: "
7715 "resume of %s deferred\n",
7716 target_pid_to_str (tp->ptid));
7719 discard_cleanups (old_cleanups);
7723 struct regcache *regcache = get_current_regcache ();
7726 step_over_what step_what;
7728 /* Either the trap was not expected, but we are continuing
7729 anyway (if we got a signal, the user asked it be passed to
7732 We got our expected trap, but decided we should resume from
7735 We're going to run this baby now!
7737 Note that insert_breakpoints won't try to re-insert
7738 already inserted breakpoints. Therefore, we don't
7739 care if breakpoints were already inserted, or not. */
7741 /* If we need to step over a breakpoint, and we're not using
7742 displaced stepping to do so, insert all breakpoints
7743 (watchpoints, etc.) but the one we're stepping over, step one
7744 instruction, and then re-insert the breakpoint when that step
7747 step_what = thread_still_needs_step_over (ecs->event_thread);
7749 remove_bp = (ecs->hit_singlestep_breakpoint
7750 || (step_what & STEP_OVER_BREAKPOINT));
7751 remove_wps = (step_what & STEP_OVER_WATCHPOINT);
7753 /* We can't use displaced stepping if we need to step past a
7754 watchpoint. The instruction copied to the scratch pad would
7755 still trigger the watchpoint. */
7757 && (remove_wps || !use_displaced_stepping (ecs->event_thread)))
7759 set_step_over_info (get_regcache_aspace (regcache),
7760 regcache_read_pc (regcache), remove_wps,
7761 ecs->event_thread->global_num);
7763 else if (remove_wps)
7764 set_step_over_info (NULL, 0, remove_wps, -1);
7766 /* If we now need to do an in-line step-over, we need to stop
7767 all other threads. Note this must be done before
7768 insert_breakpoints below, because that removes the breakpoint
7769 we're about to step over, otherwise other threads could miss
7771 if (step_over_info_valid_p () && target_is_non_stop_p ())
7772 stop_all_threads ();
7774 /* Stop stepping if inserting breakpoints fails. */
7777 insert_breakpoints ();
7779 CATCH (e, RETURN_MASK_ERROR)
7781 exception_print (gdb_stderr, e);
7783 discard_cleanups (old_cleanups);
7788 ecs->event_thread->control.trap_expected = (remove_bp || remove_wps);
7790 discard_cleanups (old_cleanups);
7791 resume (ecs->event_thread->suspend.stop_signal);
7794 prepare_to_wait (ecs);
7797 /* Called when we should continue running the inferior, because the
7798 current event doesn't cause a user visible stop. This does the
7799 resuming part; waiting for the next event is done elsewhere. */
7802 keep_going (struct execution_control_state *ecs)
7804 if (ecs->event_thread->control.trap_expected
7805 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
7806 ecs->event_thread->control.trap_expected = 0;
7808 if (!signal_program[ecs->event_thread->suspend.stop_signal])
7809 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
7810 keep_going_pass_signal (ecs);
7813 /* This function normally comes after a resume, before
7814 handle_inferior_event exits. It takes care of any last bits of
7815 housekeeping, and sets the all-important wait_some_more flag. */
7818 prepare_to_wait (struct execution_control_state *ecs)
7821 fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n");
7823 ecs->wait_some_more = 1;
7825 if (!target_is_async_p ())
7826 mark_infrun_async_event_handler ();
7829 /* We are done with the step range of a step/next/si/ni command.
7830 Called once for each n of a "step n" operation. */
7833 end_stepping_range (struct execution_control_state *ecs)
7835 ecs->event_thread->control.stop_step = 1;
7839 /* Several print_*_reason functions to print why the inferior has stopped.
7840 We always print something when the inferior exits, or receives a signal.
7841 The rest of the cases are dealt with later on in normal_stop and
7842 print_it_typical. Ideally there should be a call to one of these
7843 print_*_reason functions functions from handle_inferior_event each time
7844 stop_waiting is called.
7846 Note that we don't call these directly, instead we delegate that to
7847 the interpreters, through observers. Interpreters then call these
7848 with whatever uiout is right. */
7851 print_end_stepping_range_reason (struct ui_out *uiout)
7853 /* For CLI-like interpreters, print nothing. */
7855 if (uiout->is_mi_like_p ())
7857 uiout->field_string ("reason",
7858 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE));
7863 print_signal_exited_reason (struct ui_out *uiout, enum gdb_signal siggnal)
7865 annotate_signalled ();
7866 if (uiout->is_mi_like_p ())
7868 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED));
7869 uiout->text ("\nProgram terminated with signal ");
7870 annotate_signal_name ();
7871 uiout->field_string ("signal-name",
7872 gdb_signal_to_name (siggnal));
7873 annotate_signal_name_end ();
7875 annotate_signal_string ();
7876 uiout->field_string ("signal-meaning",
7877 gdb_signal_to_string (siggnal));
7878 annotate_signal_string_end ();
7879 uiout->text (".\n");
7880 uiout->text ("The program no longer exists.\n");
7884 print_exited_reason (struct ui_out *uiout, int exitstatus)
7886 struct inferior *inf = current_inferior ();
7887 const char *pidstr = target_pid_to_str (pid_to_ptid (inf->pid));
7889 annotate_exited (exitstatus);
7892 if (uiout->is_mi_like_p ())
7893 uiout->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED));
7894 uiout->text ("[Inferior ");
7895 uiout->text (plongest (inf->num));
7897 uiout->text (pidstr);
7898 uiout->text (") exited with code ");
7899 uiout->field_fmt ("exit-code", "0%o", (unsigned int) exitstatus);
7900 uiout->text ("]\n");
7904 if (uiout->is_mi_like_p ())
7906 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY));
7907 uiout->text ("[Inferior ");
7908 uiout->text (plongest (inf->num));
7910 uiout->text (pidstr);
7911 uiout->text (") exited normally]\n");
7915 /* Some targets/architectures can do extra processing/display of
7916 segmentation faults. E.g., Intel MPX boundary faults.
7917 Call the architecture dependent function to handle the fault. */
7920 handle_segmentation_fault (struct ui_out *uiout)
7922 struct regcache *regcache = get_current_regcache ();
7923 struct gdbarch *gdbarch = get_regcache_arch (regcache);
7925 if (gdbarch_handle_segmentation_fault_p (gdbarch))
7926 gdbarch_handle_segmentation_fault (gdbarch, uiout);
7930 print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal)
7932 struct thread_info *thr = inferior_thread ();
7936 if (uiout->is_mi_like_p ())
7938 else if (show_thread_that_caused_stop ())
7942 uiout->text ("\nThread ");
7943 uiout->field_fmt ("thread-id", "%s", print_thread_id (thr));
7945 name = thr->name != NULL ? thr->name : target_thread_name (thr);
7948 uiout->text (" \"");
7949 uiout->field_fmt ("name", "%s", name);
7954 uiout->text ("\nProgram");
7956 if (siggnal == GDB_SIGNAL_0 && !uiout->is_mi_like_p ())
7957 uiout->text (" stopped");
7960 uiout->text (" received signal ");
7961 annotate_signal_name ();
7962 if (uiout->is_mi_like_p ())
7964 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
7965 uiout->field_string ("signal-name", gdb_signal_to_name (siggnal));
7966 annotate_signal_name_end ();
7968 annotate_signal_string ();
7969 uiout->field_string ("signal-meaning", gdb_signal_to_string (siggnal));
7971 if (siggnal == GDB_SIGNAL_SEGV)
7972 handle_segmentation_fault (uiout);
7974 annotate_signal_string_end ();
7976 uiout->text (".\n");
7980 print_no_history_reason (struct ui_out *uiout)
7982 uiout->text ("\nNo more reverse-execution history.\n");
7985 /* Print current location without a level number, if we have changed
7986 functions or hit a breakpoint. Print source line if we have one.
7987 bpstat_print contains the logic deciding in detail what to print,
7988 based on the event(s) that just occurred. */
7991 print_stop_location (struct target_waitstatus *ws)
7994 enum print_what source_flag;
7995 int do_frame_printing = 1;
7996 struct thread_info *tp = inferior_thread ();
7998 bpstat_ret = bpstat_print (tp->control.stop_bpstat, ws->kind);
8002 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8003 should) carry around the function and does (or should) use
8004 that when doing a frame comparison. */
8005 if (tp->control.stop_step
8006 && frame_id_eq (tp->control.step_frame_id,
8007 get_frame_id (get_current_frame ()))
8008 && tp->control.step_start_function == find_pc_function (stop_pc))
8010 /* Finished step, just print source line. */
8011 source_flag = SRC_LINE;
8015 /* Print location and source line. */
8016 source_flag = SRC_AND_LOC;
8019 case PRINT_SRC_AND_LOC:
8020 /* Print location and source line. */
8021 source_flag = SRC_AND_LOC;
8023 case PRINT_SRC_ONLY:
8024 source_flag = SRC_LINE;
8027 /* Something bogus. */
8028 source_flag = SRC_LINE;
8029 do_frame_printing = 0;
8032 internal_error (__FILE__, __LINE__, _("Unknown value."));
8035 /* The behavior of this routine with respect to the source
8037 SRC_LINE: Print only source line
8038 LOCATION: Print only location
8039 SRC_AND_LOC: Print location and source line. */
8040 if (do_frame_printing)
8041 print_stack_frame (get_selected_frame (NULL), 0, source_flag, 1);
8047 print_stop_event (struct ui_out *uiout)
8049 struct target_waitstatus last;
8051 struct thread_info *tp;
8053 get_last_target_status (&last_ptid, &last);
8056 scoped_restore save_uiout = make_scoped_restore (¤t_uiout, uiout);
8058 print_stop_location (&last);
8060 /* Display the auto-display expressions. */
8064 tp = inferior_thread ();
8065 if (tp->thread_fsm != NULL
8066 && thread_fsm_finished_p (tp->thread_fsm))
8068 struct return_value_info *rv;
8070 rv = thread_fsm_return_value (tp->thread_fsm);
8072 print_return_value (uiout, rv);
8079 maybe_remove_breakpoints (void)
8081 if (!breakpoints_should_be_inserted_now () && target_has_execution)
8083 if (remove_breakpoints ())
8085 target_terminal::ours_for_output ();
8086 printf_filtered (_("Cannot remove breakpoints because "
8087 "program is no longer writable.\nFurther "
8088 "execution is probably impossible.\n"));
8093 /* The execution context that just caused a normal stop. */
8100 /* The event PTID. */
8104 /* If stopp for a thread event, this is the thread that caused the
8106 struct thread_info *thread;
8108 /* The inferior that caused the stop. */
8112 /* Returns a new stop context. If stopped for a thread event, this
8113 takes a strong reference to the thread. */
8115 static struct stop_context *
8116 save_stop_context (void)
8118 struct stop_context *sc = XNEW (struct stop_context);
8120 sc->stop_id = get_stop_id ();
8121 sc->ptid = inferior_ptid;
8122 sc->inf_num = current_inferior ()->num;
8124 if (!ptid_equal (inferior_ptid, null_ptid))
8126 /* Take a strong reference so that the thread can't be deleted
8128 sc->thread = inferior_thread ();
8129 sc->thread->incref ();
8137 /* Release a stop context previously created with save_stop_context.
8138 Releases the strong reference to the thread as well. */
8141 release_stop_context_cleanup (void *arg)
8143 struct stop_context *sc = (struct stop_context *) arg;
8145 if (sc->thread != NULL)
8146 sc->thread->decref ();
8150 /* Return true if the current context no longer matches the saved stop
8154 stop_context_changed (struct stop_context *prev)
8156 if (!ptid_equal (prev->ptid, inferior_ptid))
8158 if (prev->inf_num != current_inferior ()->num)
8160 if (prev->thread != NULL && prev->thread->state != THREAD_STOPPED)
8162 if (get_stop_id () != prev->stop_id)
8172 struct target_waitstatus last;
8174 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
8177 get_last_target_status (&last_ptid, &last);
8181 /* If an exception is thrown from this point on, make sure to
8182 propagate GDB's knowledge of the executing state to the
8183 frontend/user running state. A QUIT is an easy exception to see
8184 here, so do this before any filtered output. */
8186 make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
8187 else if (last.kind == TARGET_WAITKIND_SIGNALLED
8188 || last.kind == TARGET_WAITKIND_EXITED)
8190 /* On some targets, we may still have live threads in the
8191 inferior when we get a process exit event. E.g., for
8192 "checkpoint", when the current checkpoint/fork exits,
8193 linux-fork.c automatically switches to another fork from
8194 within target_mourn_inferior. */
8195 if (!ptid_equal (inferior_ptid, null_ptid))
8197 pid_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
8198 make_cleanup (finish_thread_state_cleanup, &pid_ptid);
8201 else if (last.kind != TARGET_WAITKIND_NO_RESUMED)
8202 make_cleanup (finish_thread_state_cleanup, &inferior_ptid);
8204 /* As we're presenting a stop, and potentially removing breakpoints,
8205 update the thread list so we can tell whether there are threads
8206 running on the target. With target remote, for example, we can
8207 only learn about new threads when we explicitly update the thread
8208 list. Do this before notifying the interpreters about signal
8209 stops, end of stepping ranges, etc., so that the "new thread"
8210 output is emitted before e.g., "Program received signal FOO",
8211 instead of after. */
8212 update_thread_list ();
8214 if (last.kind == TARGET_WAITKIND_STOPPED && stopped_by_random_signal)
8215 observer_notify_signal_received (inferior_thread ()->suspend.stop_signal);
8217 /* As with the notification of thread events, we want to delay
8218 notifying the user that we've switched thread context until
8219 the inferior actually stops.
8221 There's no point in saying anything if the inferior has exited.
8222 Note that SIGNALLED here means "exited with a signal", not
8223 "received a signal".
8225 Also skip saying anything in non-stop mode. In that mode, as we
8226 don't want GDB to switch threads behind the user's back, to avoid
8227 races where the user is typing a command to apply to thread x,
8228 but GDB switches to thread y before the user finishes entering
8229 the command, fetch_inferior_event installs a cleanup to restore
8230 the current thread back to the thread the user had selected right
8231 after this event is handled, so we're not really switching, only
8232 informing of a stop. */
8234 && !ptid_equal (previous_inferior_ptid, inferior_ptid)
8235 && target_has_execution
8236 && last.kind != TARGET_WAITKIND_SIGNALLED
8237 && last.kind != TARGET_WAITKIND_EXITED
8238 && last.kind != TARGET_WAITKIND_NO_RESUMED)
8240 SWITCH_THRU_ALL_UIS ()
8242 target_terminal::ours_for_output ();
8243 printf_filtered (_("[Switching to %s]\n"),
8244 target_pid_to_str (inferior_ptid));
8245 annotate_thread_changed ();
8247 previous_inferior_ptid = inferior_ptid;
8250 if (last.kind == TARGET_WAITKIND_NO_RESUMED)
8252 SWITCH_THRU_ALL_UIS ()
8253 if (current_ui->prompt_state == PROMPT_BLOCKED)
8255 target_terminal::ours_for_output ();
8256 printf_filtered (_("No unwaited-for children left.\n"));
8260 /* Note: this depends on the update_thread_list call above. */
8261 maybe_remove_breakpoints ();
8263 /* If an auto-display called a function and that got a signal,
8264 delete that auto-display to avoid an infinite recursion. */
8266 if (stopped_by_random_signal)
8267 disable_current_display ();
8269 SWITCH_THRU_ALL_UIS ()
8271 async_enable_stdin ();
8274 /* Let the user/frontend see the threads as stopped. */
8275 do_cleanups (old_chain);
8277 /* Select innermost stack frame - i.e., current frame is frame 0,
8278 and current location is based on that. Handle the case where the
8279 dummy call is returning after being stopped. E.g. the dummy call
8280 previously hit a breakpoint. (If the dummy call returns
8281 normally, we won't reach here.) Do this before the stop hook is
8282 run, so that it doesn't get to see the temporary dummy frame,
8283 which is not where we'll present the stop. */
8284 if (has_stack_frames ())
8286 if (stop_stack_dummy == STOP_STACK_DUMMY)
8288 /* Pop the empty frame that contains the stack dummy. This
8289 also restores inferior state prior to the call (struct
8290 infcall_suspend_state). */
8291 struct frame_info *frame = get_current_frame ();
8293 gdb_assert (get_frame_type (frame) == DUMMY_FRAME);
8295 /* frame_pop calls reinit_frame_cache as the last thing it
8296 does which means there's now no selected frame. */
8299 select_frame (get_current_frame ());
8301 /* Set the current source location. */
8302 set_current_sal_from_frame (get_current_frame ());
8305 /* Look up the hook_stop and run it (CLI internally handles problem
8306 of stop_command's pre-hook not existing). */
8307 if (stop_command != NULL)
8309 struct stop_context *saved_context = save_stop_context ();
8310 struct cleanup *old_chain
8311 = make_cleanup (release_stop_context_cleanup, saved_context);
8315 execute_cmd_pre_hook (stop_command);
8317 CATCH (ex, RETURN_MASK_ALL)
8319 exception_fprintf (gdb_stderr, ex,
8320 "Error while running hook_stop:\n");
8324 /* If the stop hook resumes the target, then there's no point in
8325 trying to notify about the previous stop; its context is
8326 gone. Likewise if the command switches thread or inferior --
8327 the observers would print a stop for the wrong
8329 if (stop_context_changed (saved_context))
8331 do_cleanups (old_chain);
8334 do_cleanups (old_chain);
8337 /* Notify observers about the stop. This is where the interpreters
8338 print the stop event. */
8339 if (!ptid_equal (inferior_ptid, null_ptid))
8340 observer_notify_normal_stop (inferior_thread ()->control.stop_bpstat,
8343 observer_notify_normal_stop (NULL, stop_print_frame);
8345 annotate_stopped ();
8347 if (target_has_execution)
8349 if (last.kind != TARGET_WAITKIND_SIGNALLED
8350 && last.kind != TARGET_WAITKIND_EXITED)
8351 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8352 Delete any breakpoint that is to be deleted at the next stop. */
8353 breakpoint_auto_delete (inferior_thread ()->control.stop_bpstat);
8356 /* Try to get rid of automatically added inferiors that are no
8357 longer needed. Keeping those around slows down things linearly.
8358 Note that this never removes the current inferior. */
8365 signal_stop_state (int signo)
8367 return signal_stop[signo];
8371 signal_print_state (int signo)
8373 return signal_print[signo];
8377 signal_pass_state (int signo)
8379 return signal_program[signo];
8383 signal_cache_update (int signo)
8387 for (signo = 0; signo < (int) GDB_SIGNAL_LAST; signo++)
8388 signal_cache_update (signo);
8393 signal_pass[signo] = (signal_stop[signo] == 0
8394 && signal_print[signo] == 0
8395 && signal_program[signo] == 1
8396 && signal_catch[signo] == 0);
8400 signal_stop_update (int signo, int state)
8402 int ret = signal_stop[signo];
8404 signal_stop[signo] = state;
8405 signal_cache_update (signo);
8410 signal_print_update (int signo, int state)
8412 int ret = signal_print[signo];
8414 signal_print[signo] = state;
8415 signal_cache_update (signo);
8420 signal_pass_update (int signo, int state)
8422 int ret = signal_program[signo];
8424 signal_program[signo] = state;
8425 signal_cache_update (signo);
8429 /* Update the global 'signal_catch' from INFO and notify the
8433 signal_catch_update (const unsigned int *info)
8437 for (i = 0; i < GDB_SIGNAL_LAST; ++i)
8438 signal_catch[i] = info[i] > 0;
8439 signal_cache_update (-1);
8440 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
8444 sig_print_header (void)
8446 printf_filtered (_("Signal Stop\tPrint\tPass "
8447 "to program\tDescription\n"));
8451 sig_print_info (enum gdb_signal oursig)
8453 const char *name = gdb_signal_to_name (oursig);
8454 int name_padding = 13 - strlen (name);
8456 if (name_padding <= 0)
8459 printf_filtered ("%s", name);
8460 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
8461 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
8462 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
8463 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
8464 printf_filtered ("%s\n", gdb_signal_to_string (oursig));
8467 /* Specify how various signals in the inferior should be handled. */
8470 handle_command (char *args, int from_tty)
8472 int digits, wordlen;
8473 int sigfirst, signum, siglast;
8474 enum gdb_signal oursig;
8477 unsigned char *sigs;
8481 error_no_arg (_("signal to handle"));
8484 /* Allocate and zero an array of flags for which signals to handle. */
8486 nsigs = (int) GDB_SIGNAL_LAST;
8487 sigs = (unsigned char *) alloca (nsigs);
8488 memset (sigs, 0, nsigs);
8490 /* Break the command line up into args. */
8492 gdb_argv built_argv (args);
8494 /* Walk through the args, looking for signal oursigs, signal names, and
8495 actions. Signal numbers and signal names may be interspersed with
8496 actions, with the actions being performed for all signals cumulatively
8497 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8499 for (char *arg : built_argv)
8501 wordlen = strlen (arg);
8502 for (digits = 0; isdigit (arg[digits]); digits++)
8506 sigfirst = siglast = -1;
8508 if (wordlen >= 1 && !strncmp (arg, "all", wordlen))
8510 /* Apply action to all signals except those used by the
8511 debugger. Silently skip those. */
8514 siglast = nsigs - 1;
8516 else if (wordlen >= 1 && !strncmp (arg, "stop", wordlen))
8518 SET_SIGS (nsigs, sigs, signal_stop);
8519 SET_SIGS (nsigs, sigs, signal_print);
8521 else if (wordlen >= 1 && !strncmp (arg, "ignore", wordlen))
8523 UNSET_SIGS (nsigs, sigs, signal_program);
8525 else if (wordlen >= 2 && !strncmp (arg, "print", wordlen))
8527 SET_SIGS (nsigs, sigs, signal_print);
8529 else if (wordlen >= 2 && !strncmp (arg, "pass", wordlen))
8531 SET_SIGS (nsigs, sigs, signal_program);
8533 else if (wordlen >= 3 && !strncmp (arg, "nostop", wordlen))
8535 UNSET_SIGS (nsigs, sigs, signal_stop);
8537 else if (wordlen >= 3 && !strncmp (arg, "noignore", wordlen))
8539 SET_SIGS (nsigs, sigs, signal_program);
8541 else if (wordlen >= 4 && !strncmp (arg, "noprint", wordlen))
8543 UNSET_SIGS (nsigs, sigs, signal_print);
8544 UNSET_SIGS (nsigs, sigs, signal_stop);
8546 else if (wordlen >= 4 && !strncmp (arg, "nopass", wordlen))
8548 UNSET_SIGS (nsigs, sigs, signal_program);
8550 else if (digits > 0)
8552 /* It is numeric. The numeric signal refers to our own
8553 internal signal numbering from target.h, not to host/target
8554 signal number. This is a feature; users really should be
8555 using symbolic names anyway, and the common ones like
8556 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8558 sigfirst = siglast = (int)
8559 gdb_signal_from_command (atoi (arg));
8560 if (arg[digits] == '-')
8563 gdb_signal_from_command (atoi (arg + digits + 1));
8565 if (sigfirst > siglast)
8567 /* Bet he didn't figure we'd think of this case... */
8575 oursig = gdb_signal_from_name (arg);
8576 if (oursig != GDB_SIGNAL_UNKNOWN)
8578 sigfirst = siglast = (int) oursig;
8582 /* Not a number and not a recognized flag word => complain. */
8583 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg);
8587 /* If any signal numbers or symbol names were found, set flags for
8588 which signals to apply actions to. */
8590 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
8592 switch ((enum gdb_signal) signum)
8594 case GDB_SIGNAL_TRAP:
8595 case GDB_SIGNAL_INT:
8596 if (!allsigs && !sigs[signum])
8598 if (query (_("%s is used by the debugger.\n\
8599 Are you sure you want to change it? "),
8600 gdb_signal_to_name ((enum gdb_signal) signum)))
8606 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8607 gdb_flush (gdb_stdout);
8612 case GDB_SIGNAL_DEFAULT:
8613 case GDB_SIGNAL_UNKNOWN:
8614 /* Make sure that "all" doesn't print these. */
8623 for (signum = 0; signum < nsigs; signum++)
8626 signal_cache_update (-1);
8627 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
8628 target_program_signals ((int) GDB_SIGNAL_LAST, signal_program);
8632 /* Show the results. */
8633 sig_print_header ();
8634 for (; signum < nsigs; signum++)
8636 sig_print_info ((enum gdb_signal) signum);
8643 /* Complete the "handle" command. */
8646 handle_completer (struct cmd_list_element *ignore,
8647 completion_tracker &tracker,
8648 const char *text, const char *word)
8650 static const char * const keywords[] =
8664 signal_completer (ignore, tracker, text, word);
8665 complete_on_enum (tracker, keywords, word, word);
8669 gdb_signal_from_command (int num)
8671 if (num >= 1 && num <= 15)
8672 return (enum gdb_signal) num;
8673 error (_("Only signals 1-15 are valid as numeric signals.\n\
8674 Use \"info signals\" for a list of symbolic signals."));
8677 /* Print current contents of the tables set by the handle command.
8678 It is possible we should just be printing signals actually used
8679 by the current target (but for things to work right when switching
8680 targets, all signals should be in the signal tables). */
8683 info_signals_command (char *signum_exp, int from_tty)
8685 enum gdb_signal oursig;
8687 sig_print_header ();
8691 /* First see if this is a symbol name. */
8692 oursig = gdb_signal_from_name (signum_exp);
8693 if (oursig == GDB_SIGNAL_UNKNOWN)
8695 /* No, try numeric. */
8697 gdb_signal_from_command (parse_and_eval_long (signum_exp));
8699 sig_print_info (oursig);
8703 printf_filtered ("\n");
8704 /* These ugly casts brought to you by the native VAX compiler. */
8705 for (oursig = GDB_SIGNAL_FIRST;
8706 (int) oursig < (int) GDB_SIGNAL_LAST;
8707 oursig = (enum gdb_signal) ((int) oursig + 1))
8711 if (oursig != GDB_SIGNAL_UNKNOWN
8712 && oursig != GDB_SIGNAL_DEFAULT && oursig != GDB_SIGNAL_0)
8713 sig_print_info (oursig);
8716 printf_filtered (_("\nUse the \"handle\" command "
8717 "to change these tables.\n"));
8720 /* The $_siginfo convenience variable is a bit special. We don't know
8721 for sure the type of the value until we actually have a chance to
8722 fetch the data. The type can change depending on gdbarch, so it is
8723 also dependent on which thread you have selected.
8725 1. making $_siginfo be an internalvar that creates a new value on
8728 2. making the value of $_siginfo be an lval_computed value. */
8730 /* This function implements the lval_computed support for reading a
8734 siginfo_value_read (struct value *v)
8736 LONGEST transferred;
8738 /* If we can access registers, so can we access $_siginfo. Likewise
8740 validate_registers_access ();
8743 target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO,
8745 value_contents_all_raw (v),
8747 TYPE_LENGTH (value_type (v)));
8749 if (transferred != TYPE_LENGTH (value_type (v)))
8750 error (_("Unable to read siginfo"));
8753 /* This function implements the lval_computed support for writing a
8757 siginfo_value_write (struct value *v, struct value *fromval)
8759 LONGEST transferred;
8761 /* If we can access registers, so can we access $_siginfo. Likewise
8763 validate_registers_access ();
8765 transferred = target_write (¤t_target,
8766 TARGET_OBJECT_SIGNAL_INFO,
8768 value_contents_all_raw (fromval),
8770 TYPE_LENGTH (value_type (fromval)));
8772 if (transferred != TYPE_LENGTH (value_type (fromval)))
8773 error (_("Unable to write siginfo"));
8776 static const struct lval_funcs siginfo_value_funcs =
8782 /* Return a new value with the correct type for the siginfo object of
8783 the current thread using architecture GDBARCH. Return a void value
8784 if there's no object available. */
8786 static struct value *
8787 siginfo_make_value (struct gdbarch *gdbarch, struct internalvar *var,
8790 if (target_has_stack
8791 && !ptid_equal (inferior_ptid, null_ptid)
8792 && gdbarch_get_siginfo_type_p (gdbarch))
8794 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8796 return allocate_computed_value (type, &siginfo_value_funcs, NULL);
8799 return allocate_value (builtin_type (gdbarch)->builtin_void);
8803 /* infcall_suspend_state contains state about the program itself like its
8804 registers and any signal it received when it last stopped.
8805 This state must be restored regardless of how the inferior function call
8806 ends (either successfully, or after it hits a breakpoint or signal)
8807 if the program is to properly continue where it left off. */
8809 struct infcall_suspend_state
8811 struct thread_suspend_state thread_suspend;
8815 struct regcache *registers;
8817 /* Format of SIGINFO_DATA or NULL if it is not present. */
8818 struct gdbarch *siginfo_gdbarch;
8820 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8821 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8822 content would be invalid. */
8823 gdb_byte *siginfo_data;
8826 struct infcall_suspend_state *
8827 save_infcall_suspend_state (void)
8829 struct infcall_suspend_state *inf_state;
8830 struct thread_info *tp = inferior_thread ();
8831 struct regcache *regcache = get_current_regcache ();
8832 struct gdbarch *gdbarch = get_regcache_arch (regcache);
8833 gdb_byte *siginfo_data = NULL;
8835 if (gdbarch_get_siginfo_type_p (gdbarch))
8837 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8838 size_t len = TYPE_LENGTH (type);
8839 struct cleanup *back_to;
8841 siginfo_data = (gdb_byte *) xmalloc (len);
8842 back_to = make_cleanup (xfree, siginfo_data);
8844 if (target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
8845 siginfo_data, 0, len) == len)
8846 discard_cleanups (back_to);
8849 /* Errors ignored. */
8850 do_cleanups (back_to);
8851 siginfo_data = NULL;
8855 inf_state = XCNEW (struct infcall_suspend_state);
8859 inf_state->siginfo_gdbarch = gdbarch;
8860 inf_state->siginfo_data = siginfo_data;
8863 inf_state->thread_suspend = tp->suspend;
8865 /* run_inferior_call will not use the signal due to its `proceed' call with
8866 GDB_SIGNAL_0 anyway. */
8867 tp->suspend.stop_signal = GDB_SIGNAL_0;
8869 inf_state->stop_pc = stop_pc;
8871 inf_state->registers = regcache_dup (regcache);
8876 /* Restore inferior session state to INF_STATE. */
8879 restore_infcall_suspend_state (struct infcall_suspend_state *inf_state)
8881 struct thread_info *tp = inferior_thread ();
8882 struct regcache *regcache = get_current_regcache ();
8883 struct gdbarch *gdbarch = get_regcache_arch (regcache);
8885 tp->suspend = inf_state->thread_suspend;
8887 stop_pc = inf_state->stop_pc;
8889 if (inf_state->siginfo_gdbarch == gdbarch)
8891 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8893 /* Errors ignored. */
8894 target_write (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
8895 inf_state->siginfo_data, 0, TYPE_LENGTH (type));
8898 /* The inferior can be gone if the user types "print exit(0)"
8899 (and perhaps other times). */
8900 if (target_has_execution)
8901 /* NB: The register write goes through to the target. */
8902 regcache_cpy (regcache, inf_state->registers);
8904 discard_infcall_suspend_state (inf_state);
8908 do_restore_infcall_suspend_state_cleanup (void *state)
8910 restore_infcall_suspend_state ((struct infcall_suspend_state *) state);
8914 make_cleanup_restore_infcall_suspend_state
8915 (struct infcall_suspend_state *inf_state)
8917 return make_cleanup (do_restore_infcall_suspend_state_cleanup, inf_state);
8921 discard_infcall_suspend_state (struct infcall_suspend_state *inf_state)
8923 delete inf_state->registers;
8924 xfree (inf_state->siginfo_data);
8929 get_infcall_suspend_state_regcache (struct infcall_suspend_state *inf_state)
8931 return inf_state->registers;
8934 /* infcall_control_state contains state regarding gdb's control of the
8935 inferior itself like stepping control. It also contains session state like
8936 the user's currently selected frame. */
8938 struct infcall_control_state
8940 struct thread_control_state thread_control;
8941 struct inferior_control_state inferior_control;
8944 enum stop_stack_kind stop_stack_dummy;
8945 int stopped_by_random_signal;
8947 /* ID if the selected frame when the inferior function call was made. */
8948 struct frame_id selected_frame_id;
8951 /* Save all of the information associated with the inferior<==>gdb
8954 struct infcall_control_state *
8955 save_infcall_control_state (void)
8957 struct infcall_control_state *inf_status =
8958 XNEW (struct infcall_control_state);
8959 struct thread_info *tp = inferior_thread ();
8960 struct inferior *inf = current_inferior ();
8962 inf_status->thread_control = tp->control;
8963 inf_status->inferior_control = inf->control;
8965 tp->control.step_resume_breakpoint = NULL;
8966 tp->control.exception_resume_breakpoint = NULL;
8968 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
8969 chain. If caller's caller is walking the chain, they'll be happier if we
8970 hand them back the original chain when restore_infcall_control_state is
8972 tp->control.stop_bpstat = bpstat_copy (tp->control.stop_bpstat);
8975 inf_status->stop_stack_dummy = stop_stack_dummy;
8976 inf_status->stopped_by_random_signal = stopped_by_random_signal;
8978 inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL));
8984 restore_selected_frame (const frame_id &fid)
8986 frame_info *frame = frame_find_by_id (fid);
8988 /* If inf_status->selected_frame_id is NULL, there was no previously
8992 warning (_("Unable to restore previously selected frame."));
8996 select_frame (frame);
8999 /* Restore inferior session state to INF_STATUS. */
9002 restore_infcall_control_state (struct infcall_control_state *inf_status)
9004 struct thread_info *tp = inferior_thread ();
9005 struct inferior *inf = current_inferior ();
9007 if (tp->control.step_resume_breakpoint)
9008 tp->control.step_resume_breakpoint->disposition = disp_del_at_next_stop;
9010 if (tp->control.exception_resume_breakpoint)
9011 tp->control.exception_resume_breakpoint->disposition
9012 = disp_del_at_next_stop;
9014 /* Handle the bpstat_copy of the chain. */
9015 bpstat_clear (&tp->control.stop_bpstat);
9017 tp->control = inf_status->thread_control;
9018 inf->control = inf_status->inferior_control;
9021 stop_stack_dummy = inf_status->stop_stack_dummy;
9022 stopped_by_random_signal = inf_status->stopped_by_random_signal;
9024 if (target_has_stack)
9026 /* The point of the try/catch is that if the stack is clobbered,
9027 walking the stack might encounter a garbage pointer and
9028 error() trying to dereference it. */
9031 restore_selected_frame (inf_status->selected_frame_id);
9033 CATCH (ex, RETURN_MASK_ERROR)
9035 exception_fprintf (gdb_stderr, ex,
9036 "Unable to restore previously selected frame:\n");
9037 /* Error in restoring the selected frame. Select the
9039 select_frame (get_current_frame ());
9048 do_restore_infcall_control_state_cleanup (void *sts)
9050 restore_infcall_control_state ((struct infcall_control_state *) sts);
9054 make_cleanup_restore_infcall_control_state
9055 (struct infcall_control_state *inf_status)
9057 return make_cleanup (do_restore_infcall_control_state_cleanup, inf_status);
9061 discard_infcall_control_state (struct infcall_control_state *inf_status)
9063 if (inf_status->thread_control.step_resume_breakpoint)
9064 inf_status->thread_control.step_resume_breakpoint->disposition
9065 = disp_del_at_next_stop;
9067 if (inf_status->thread_control.exception_resume_breakpoint)
9068 inf_status->thread_control.exception_resume_breakpoint->disposition
9069 = disp_del_at_next_stop;
9071 /* See save_infcall_control_state for info on stop_bpstat. */
9072 bpstat_clear (&inf_status->thread_control.stop_bpstat);
9080 clear_exit_convenience_vars (void)
9082 clear_internalvar (lookup_internalvar ("_exitsignal"));
9083 clear_internalvar (lookup_internalvar ("_exitcode"));
9087 /* User interface for reverse debugging:
9088 Set exec-direction / show exec-direction commands
9089 (returns error unless target implements to_set_exec_direction method). */
9091 enum exec_direction_kind execution_direction = EXEC_FORWARD;
9092 static const char exec_forward[] = "forward";
9093 static const char exec_reverse[] = "reverse";
9094 static const char *exec_direction = exec_forward;
9095 static const char *const exec_direction_names[] = {
9102 set_exec_direction_func (char *args, int from_tty,
9103 struct cmd_list_element *cmd)
9105 if (target_can_execute_reverse)
9107 if (!strcmp (exec_direction, exec_forward))
9108 execution_direction = EXEC_FORWARD;
9109 else if (!strcmp (exec_direction, exec_reverse))
9110 execution_direction = EXEC_REVERSE;
9114 exec_direction = exec_forward;
9115 error (_("Target does not support this operation."));
9120 show_exec_direction_func (struct ui_file *out, int from_tty,
9121 struct cmd_list_element *cmd, const char *value)
9123 switch (execution_direction) {
9125 fprintf_filtered (out, _("Forward.\n"));
9128 fprintf_filtered (out, _("Reverse.\n"));
9131 internal_error (__FILE__, __LINE__,
9132 _("bogus execution_direction value: %d"),
9133 (int) execution_direction);
9138 show_schedule_multiple (struct ui_file *file, int from_tty,
9139 struct cmd_list_element *c, const char *value)
9141 fprintf_filtered (file, _("Resuming the execution of threads "
9142 "of all processes is %s.\n"), value);
9145 /* Implementation of `siginfo' variable. */
9147 static const struct internalvar_funcs siginfo_funcs =
9154 /* Callback for infrun's target events source. This is marked when a
9155 thread has a pending status to process. */
9158 infrun_async_inferior_event_handler (gdb_client_data data)
9160 inferior_event_handler (INF_REG_EVENT, NULL);
9164 _initialize_infrun (void)
9168 struct cmd_list_element *c;
9170 /* Register extra event sources in the event loop. */
9171 infrun_async_inferior_event_token
9172 = create_async_event_handler (infrun_async_inferior_event_handler, NULL);
9174 add_info ("signals", info_signals_command, _("\
9175 What debugger does when program gets various signals.\n\
9176 Specify a signal as argument to print info on that signal only."));
9177 add_info_alias ("handle", "signals", 0);
9179 c = add_com ("handle", class_run, handle_command, _("\
9180 Specify how to handle signals.\n\
9181 Usage: handle SIGNAL [ACTIONS]\n\
9182 Args are signals and actions to apply to those signals.\n\
9183 If no actions are specified, the current settings for the specified signals\n\
9184 will be displayed instead.\n\
9186 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9187 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9188 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9189 The special arg \"all\" is recognized to mean all signals except those\n\
9190 used by the debugger, typically SIGTRAP and SIGINT.\n\
9192 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9193 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9194 Stop means reenter debugger if this signal happens (implies print).\n\
9195 Print means print a message if this signal happens.\n\
9196 Pass means let program see this signal; otherwise program doesn't know.\n\
9197 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9198 Pass and Stop may be combined.\n\
9200 Multiple signals may be specified. Signal numbers and signal names\n\
9201 may be interspersed with actions, with the actions being performed for\n\
9202 all signals cumulatively specified."));
9203 set_cmd_completer (c, handle_completer);
9206 stop_command = add_cmd ("stop", class_obscure,
9207 not_just_help_class_command, _("\
9208 There is no `stop' command, but you can set a hook on `stop'.\n\
9209 This allows you to set a list of commands to be run each time execution\n\
9210 of the program stops."), &cmdlist);
9212 add_setshow_zuinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\
9213 Set inferior debugging."), _("\
9214 Show inferior debugging."), _("\
9215 When non-zero, inferior specific debugging is enabled."),
9218 &setdebuglist, &showdebuglist);
9220 add_setshow_boolean_cmd ("displaced", class_maintenance,
9221 &debug_displaced, _("\
9222 Set displaced stepping debugging."), _("\
9223 Show displaced stepping debugging."), _("\
9224 When non-zero, displaced stepping specific debugging is enabled."),
9226 show_debug_displaced,
9227 &setdebuglist, &showdebuglist);
9229 add_setshow_boolean_cmd ("non-stop", no_class,
9231 Set whether gdb controls the inferior in non-stop mode."), _("\
9232 Show whether gdb controls the inferior in non-stop mode."), _("\
9233 When debugging a multi-threaded program and this setting is\n\
9234 off (the default, also called all-stop mode), when one thread stops\n\
9235 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9236 all other threads in the program while you interact with the thread of\n\
9237 interest. When you continue or step a thread, you can allow the other\n\
9238 threads to run, or have them remain stopped, but while you inspect any\n\
9239 thread's state, all threads stop.\n\
9241 In non-stop mode, when one thread stops, other threads can continue\n\
9242 to run freely. You'll be able to step each thread independently,\n\
9243 leave it stopped or free to run as needed."),
9249 numsigs = (int) GDB_SIGNAL_LAST;
9250 signal_stop = XNEWVEC (unsigned char, numsigs);
9251 signal_print = XNEWVEC (unsigned char, numsigs);
9252 signal_program = XNEWVEC (unsigned char, numsigs);
9253 signal_catch = XNEWVEC (unsigned char, numsigs);
9254 signal_pass = XNEWVEC (unsigned char, numsigs);
9255 for (i = 0; i < numsigs; i++)
9258 signal_print[i] = 1;
9259 signal_program[i] = 1;
9260 signal_catch[i] = 0;
9263 /* Signals caused by debugger's own actions should not be given to
9264 the program afterwards.
9266 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9267 explicitly specifies that it should be delivered to the target
9268 program. Typically, that would occur when a user is debugging a
9269 target monitor on a simulator: the target monitor sets a
9270 breakpoint; the simulator encounters this breakpoint and halts
9271 the simulation handing control to GDB; GDB, noting that the stop
9272 address doesn't map to any known breakpoint, returns control back
9273 to the simulator; the simulator then delivers the hardware
9274 equivalent of a GDB_SIGNAL_TRAP to the program being
9276 signal_program[GDB_SIGNAL_TRAP] = 0;
9277 signal_program[GDB_SIGNAL_INT] = 0;
9279 /* Signals that are not errors should not normally enter the debugger. */
9280 signal_stop[GDB_SIGNAL_ALRM] = 0;
9281 signal_print[GDB_SIGNAL_ALRM] = 0;
9282 signal_stop[GDB_SIGNAL_VTALRM] = 0;
9283 signal_print[GDB_SIGNAL_VTALRM] = 0;
9284 signal_stop[GDB_SIGNAL_PROF] = 0;
9285 signal_print[GDB_SIGNAL_PROF] = 0;
9286 signal_stop[GDB_SIGNAL_CHLD] = 0;
9287 signal_print[GDB_SIGNAL_CHLD] = 0;
9288 signal_stop[GDB_SIGNAL_IO] = 0;
9289 signal_print[GDB_SIGNAL_IO] = 0;
9290 signal_stop[GDB_SIGNAL_POLL] = 0;
9291 signal_print[GDB_SIGNAL_POLL] = 0;
9292 signal_stop[GDB_SIGNAL_URG] = 0;
9293 signal_print[GDB_SIGNAL_URG] = 0;
9294 signal_stop[GDB_SIGNAL_WINCH] = 0;
9295 signal_print[GDB_SIGNAL_WINCH] = 0;
9296 signal_stop[GDB_SIGNAL_PRIO] = 0;
9297 signal_print[GDB_SIGNAL_PRIO] = 0;
9299 /* These signals are used internally by user-level thread
9300 implementations. (See signal(5) on Solaris.) Like the above
9301 signals, a healthy program receives and handles them as part of
9302 its normal operation. */
9303 signal_stop[GDB_SIGNAL_LWP] = 0;
9304 signal_print[GDB_SIGNAL_LWP] = 0;
9305 signal_stop[GDB_SIGNAL_WAITING] = 0;
9306 signal_print[GDB_SIGNAL_WAITING] = 0;
9307 signal_stop[GDB_SIGNAL_CANCEL] = 0;
9308 signal_print[GDB_SIGNAL_CANCEL] = 0;
9309 signal_stop[GDB_SIGNAL_LIBRT] = 0;
9310 signal_print[GDB_SIGNAL_LIBRT] = 0;
9312 /* Update cached state. */
9313 signal_cache_update (-1);
9315 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support,
9316 &stop_on_solib_events, _("\
9317 Set stopping for shared library events."), _("\
9318 Show stopping for shared library events."), _("\
9319 If nonzero, gdb will give control to the user when the dynamic linker\n\
9320 notifies gdb of shared library events. The most common event of interest\n\
9321 to the user would be loading/unloading of a new library."),
9322 set_stop_on_solib_events,
9323 show_stop_on_solib_events,
9324 &setlist, &showlist);
9326 add_setshow_enum_cmd ("follow-fork-mode", class_run,
9327 follow_fork_mode_kind_names,
9328 &follow_fork_mode_string, _("\
9329 Set debugger response to a program call of fork or vfork."), _("\
9330 Show debugger response to a program call of fork or vfork."), _("\
9331 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9332 parent - the original process is debugged after a fork\n\
9333 child - the new process is debugged after a fork\n\
9334 The unfollowed process will continue to run.\n\
9335 By default, the debugger will follow the parent process."),
9337 show_follow_fork_mode_string,
9338 &setlist, &showlist);
9340 add_setshow_enum_cmd ("follow-exec-mode", class_run,
9341 follow_exec_mode_names,
9342 &follow_exec_mode_string, _("\
9343 Set debugger response to a program call of exec."), _("\
9344 Show debugger response to a program call of exec."), _("\
9345 An exec call replaces the program image of a process.\n\
9347 follow-exec-mode can be:\n\
9349 new - the debugger creates a new inferior and rebinds the process\n\
9350 to this new inferior. The program the process was running before\n\
9351 the exec call can be restarted afterwards by restarting the original\n\
9354 same - the debugger keeps the process bound to the same inferior.\n\
9355 The new executable image replaces the previous executable loaded in\n\
9356 the inferior. Restarting the inferior after the exec call restarts\n\
9357 the executable the process was running after the exec call.\n\
9359 By default, the debugger will use the same inferior."),
9361 show_follow_exec_mode_string,
9362 &setlist, &showlist);
9364 add_setshow_enum_cmd ("scheduler-locking", class_run,
9365 scheduler_enums, &scheduler_mode, _("\
9366 Set mode for locking scheduler during execution."), _("\
9367 Show mode for locking scheduler during execution."), _("\
9368 off == no locking (threads may preempt at any time)\n\
9369 on == full locking (no thread except the current thread may run)\n\
9370 This applies to both normal execution and replay mode.\n\
9371 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9372 In this mode, other threads may run during other commands.\n\
9373 This applies to both normal execution and replay mode.\n\
9374 replay == scheduler locked in replay mode and unlocked during normal execution."),
9375 set_schedlock_func, /* traps on target vector */
9376 show_scheduler_mode,
9377 &setlist, &showlist);
9379 add_setshow_boolean_cmd ("schedule-multiple", class_run, &sched_multi, _("\
9380 Set mode for resuming threads of all processes."), _("\
9381 Show mode for resuming threads of all processes."), _("\
9382 When on, execution commands (such as 'continue' or 'next') resume all\n\
9383 threads of all processes. When off (which is the default), execution\n\
9384 commands only resume the threads of the current process. The set of\n\
9385 threads that are resumed is further refined by the scheduler-locking\n\
9386 mode (see help set scheduler-locking)."),
9388 show_schedule_multiple,
9389 &setlist, &showlist);
9391 add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\
9392 Set mode of the step operation."), _("\
9393 Show mode of the step operation."), _("\
9394 When set, doing a step over a function without debug line information\n\
9395 will stop at the first instruction of that function. Otherwise, the\n\
9396 function is skipped and the step command stops at a different source line."),
9398 show_step_stop_if_no_debug,
9399 &setlist, &showlist);
9401 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run,
9402 &can_use_displaced_stepping, _("\
9403 Set debugger's willingness to use displaced stepping."), _("\
9404 Show debugger's willingness to use displaced stepping."), _("\
9405 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9406 supported by the target architecture. If off, gdb will not use displaced\n\
9407 stepping to step over breakpoints, even if such is supported by the target\n\
9408 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9409 if the target architecture supports it and non-stop mode is active, but will not\n\
9410 use it in all-stop mode (see help set non-stop)."),
9412 show_can_use_displaced_stepping,
9413 &setlist, &showlist);
9415 add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names,
9416 &exec_direction, _("Set direction of execution.\n\
9417 Options are 'forward' or 'reverse'."),
9418 _("Show direction of execution (forward/reverse)."),
9419 _("Tells gdb whether to execute forward or backward."),
9420 set_exec_direction_func, show_exec_direction_func,
9421 &setlist, &showlist);
9423 /* Set/show detach-on-fork: user-settable mode. */
9425 add_setshow_boolean_cmd ("detach-on-fork", class_run, &detach_fork, _("\
9426 Set whether gdb will detach the child of a fork."), _("\
9427 Show whether gdb will detach the child of a fork."), _("\
9428 Tells gdb whether to detach the child of a fork."),
9429 NULL, NULL, &setlist, &showlist);
9431 /* Set/show disable address space randomization mode. */
9433 add_setshow_boolean_cmd ("disable-randomization", class_support,
9434 &disable_randomization, _("\
9435 Set disabling of debuggee's virtual address space randomization."), _("\
9436 Show disabling of debuggee's virtual address space randomization."), _("\
9437 When this mode is on (which is the default), randomization of the virtual\n\
9438 address space is disabled. Standalone programs run with the randomization\n\
9439 enabled by default on some platforms."),
9440 &set_disable_randomization,
9441 &show_disable_randomization,
9442 &setlist, &showlist);
9444 /* ptid initializations */
9445 inferior_ptid = null_ptid;
9446 target_last_wait_ptid = minus_one_ptid;
9448 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed);
9449 observer_attach_thread_stop_requested (infrun_thread_stop_requested);
9450 observer_attach_thread_exit (infrun_thread_thread_exit);
9451 observer_attach_inferior_exit (infrun_inferior_exit);
9453 /* Explicitly create without lookup, since that tries to create a
9454 value with a void typed value, and when we get here, gdbarch
9455 isn't initialized yet. At this point, we're quite sure there
9456 isn't another convenience variable of the same name. */
9457 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs, NULL);
9459 add_setshow_boolean_cmd ("observer", no_class,
9460 &observer_mode_1, _("\
9461 Set whether gdb controls the inferior in observer mode."), _("\
9462 Show whether gdb controls the inferior in observer mode."), _("\
9463 In observer mode, GDB can get data from the inferior, but not\n\
9464 affect its execution. Registers and memory may not be changed,\n\
9465 breakpoints may not be set, and the program cannot be interrupted\n\