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"
70 /* Prototypes for local functions */
72 static void signals_info (char *, int);
74 static void handle_command (char *, int);
76 static void sig_print_info (enum gdb_signal);
78 static void sig_print_header (void);
80 static void resume_cleanups (void *);
82 static int hook_stop_stub (void *);
84 static int restore_selected_frame (void *);
86 static int follow_fork (void);
88 static int follow_fork_inferior (int follow_child, int detach_fork);
90 static void follow_inferior_reset_breakpoints (void);
92 static void set_schedlock_func (char *args, int from_tty,
93 struct cmd_list_element *c);
95 static int currently_stepping (struct thread_info *tp);
97 void _initialize_infrun (void);
99 void nullify_last_target_wait_ptid (void);
101 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info *);
103 static void insert_step_resume_breakpoint_at_caller (struct frame_info *);
105 static void insert_longjmp_resume_breakpoint (struct gdbarch *, CORE_ADDR);
107 static int maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc);
109 /* Asynchronous signal handler registered as event loop source for
110 when we have pending events ready to be passed to the core. */
111 static struct async_event_handler *infrun_async_inferior_event_token;
113 /* Stores whether infrun_async was previously enabled or disabled.
114 Starts off as -1, indicating "never enabled/disabled". */
115 static int infrun_is_async = -1;
120 infrun_async (int enable)
122 if (infrun_is_async != enable)
124 infrun_is_async = enable;
127 fprintf_unfiltered (gdb_stdlog,
128 "infrun: infrun_async(%d)\n",
132 mark_async_event_handler (infrun_async_inferior_event_token);
134 clear_async_event_handler (infrun_async_inferior_event_token);
141 mark_infrun_async_event_handler (void)
143 mark_async_event_handler (infrun_async_inferior_event_token);
146 /* When set, stop the 'step' command if we enter a function which has
147 no line number information. The normal behavior is that we step
148 over such function. */
149 int step_stop_if_no_debug = 0;
151 show_step_stop_if_no_debug (struct ui_file *file, int from_tty,
152 struct cmd_list_element *c, const char *value)
154 fprintf_filtered (file, _("Mode of the step operation is %s.\n"), value);
157 /* proceed and normal_stop use this to notify the user when the
158 inferior stopped in a different thread than it had been running
161 static ptid_t previous_inferior_ptid;
163 /* If set (default for legacy reasons), when following a fork, GDB
164 will detach from one of the fork branches, child or parent.
165 Exactly which branch is detached depends on 'set follow-fork-mode'
168 static int detach_fork = 1;
170 int debug_displaced = 0;
172 show_debug_displaced (struct ui_file *file, int from_tty,
173 struct cmd_list_element *c, const char *value)
175 fprintf_filtered (file, _("Displace stepping debugging is %s.\n"), value);
178 unsigned int debug_infrun = 0;
180 show_debug_infrun (struct ui_file *file, int from_tty,
181 struct cmd_list_element *c, const char *value)
183 fprintf_filtered (file, _("Inferior debugging is %s.\n"), value);
187 /* Support for disabling address space randomization. */
189 int disable_randomization = 1;
192 show_disable_randomization (struct ui_file *file, int from_tty,
193 struct cmd_list_element *c, const char *value)
195 if (target_supports_disable_randomization ())
196 fprintf_filtered (file,
197 _("Disabling randomization of debuggee's "
198 "virtual address space is %s.\n"),
201 fputs_filtered (_("Disabling randomization of debuggee's "
202 "virtual address space is unsupported on\n"
203 "this platform.\n"), file);
207 set_disable_randomization (char *args, int from_tty,
208 struct cmd_list_element *c)
210 if (!target_supports_disable_randomization ())
211 error (_("Disabling randomization of debuggee's "
212 "virtual address space is unsupported on\n"
216 /* User interface for non-stop mode. */
219 static int non_stop_1 = 0;
222 set_non_stop (char *args, int from_tty,
223 struct cmd_list_element *c)
225 if (target_has_execution)
227 non_stop_1 = non_stop;
228 error (_("Cannot change this setting while the inferior is running."));
231 non_stop = non_stop_1;
235 show_non_stop (struct ui_file *file, int from_tty,
236 struct cmd_list_element *c, const char *value)
238 fprintf_filtered (file,
239 _("Controlling the inferior in non-stop mode is %s.\n"),
243 /* "Observer mode" is somewhat like a more extreme version of
244 non-stop, in which all GDB operations that might affect the
245 target's execution have been disabled. */
247 int observer_mode = 0;
248 static int observer_mode_1 = 0;
251 set_observer_mode (char *args, int from_tty,
252 struct cmd_list_element *c)
254 if (target_has_execution)
256 observer_mode_1 = observer_mode;
257 error (_("Cannot change this setting while the inferior is running."));
260 observer_mode = observer_mode_1;
262 may_write_registers = !observer_mode;
263 may_write_memory = !observer_mode;
264 may_insert_breakpoints = !observer_mode;
265 may_insert_tracepoints = !observer_mode;
266 /* We can insert fast tracepoints in or out of observer mode,
267 but enable them if we're going into this mode. */
269 may_insert_fast_tracepoints = 1;
270 may_stop = !observer_mode;
271 update_target_permissions ();
273 /* Going *into* observer mode we must force non-stop, then
274 going out we leave it that way. */
277 pagination_enabled = 0;
278 non_stop = non_stop_1 = 1;
282 printf_filtered (_("Observer mode is now %s.\n"),
283 (observer_mode ? "on" : "off"));
287 show_observer_mode (struct ui_file *file, int from_tty,
288 struct cmd_list_element *c, const char *value)
290 fprintf_filtered (file, _("Observer mode is %s.\n"), value);
293 /* This updates the value of observer mode based on changes in
294 permissions. Note that we are deliberately ignoring the values of
295 may-write-registers and may-write-memory, since the user may have
296 reason to enable these during a session, for instance to turn on a
297 debugging-related global. */
300 update_observer_mode (void)
304 newval = (!may_insert_breakpoints
305 && !may_insert_tracepoints
306 && may_insert_fast_tracepoints
310 /* Let the user know if things change. */
311 if (newval != observer_mode)
312 printf_filtered (_("Observer mode is now %s.\n"),
313 (newval ? "on" : "off"));
315 observer_mode = observer_mode_1 = newval;
318 /* Tables of how to react to signals; the user sets them. */
320 static unsigned char *signal_stop;
321 static unsigned char *signal_print;
322 static unsigned char *signal_program;
324 /* Table of signals that are registered with "catch signal". A
325 non-zero entry indicates that the signal is caught by some "catch
326 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
328 static unsigned char *signal_catch;
330 /* Table of signals that the target may silently handle.
331 This is automatically determined from the flags above,
332 and simply cached here. */
333 static unsigned char *signal_pass;
335 #define SET_SIGS(nsigs,sigs,flags) \
337 int signum = (nsigs); \
338 while (signum-- > 0) \
339 if ((sigs)[signum]) \
340 (flags)[signum] = 1; \
343 #define UNSET_SIGS(nsigs,sigs,flags) \
345 int signum = (nsigs); \
346 while (signum-- > 0) \
347 if ((sigs)[signum]) \
348 (flags)[signum] = 0; \
351 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
352 this function is to avoid exporting `signal_program'. */
355 update_signals_program_target (void)
357 target_program_signals ((int) GDB_SIGNAL_LAST, signal_program);
360 /* Value to pass to target_resume() to cause all threads to resume. */
362 #define RESUME_ALL minus_one_ptid
364 /* Command list pointer for the "stop" placeholder. */
366 static struct cmd_list_element *stop_command;
368 /* Nonzero if we want to give control to the user when we're notified
369 of shared library events by the dynamic linker. */
370 int stop_on_solib_events;
372 /* Enable or disable optional shared library event breakpoints
373 as appropriate when the above flag is changed. */
376 set_stop_on_solib_events (char *args, int from_tty, struct cmd_list_element *c)
378 update_solib_breakpoints ();
382 show_stop_on_solib_events (struct ui_file *file, int from_tty,
383 struct cmd_list_element *c, const char *value)
385 fprintf_filtered (file, _("Stopping for shared library events is %s.\n"),
389 /* Nonzero after stop if current stack frame should be printed. */
391 static int stop_print_frame;
393 /* This is a cached copy of the pid/waitstatus of the last event
394 returned by target_wait()/deprecated_target_wait_hook(). This
395 information is returned by get_last_target_status(). */
396 static ptid_t target_last_wait_ptid;
397 static struct target_waitstatus target_last_waitstatus;
399 static void context_switch (ptid_t ptid);
401 void init_thread_stepping_state (struct thread_info *tss);
403 static const char follow_fork_mode_child[] = "child";
404 static const char follow_fork_mode_parent[] = "parent";
406 static const char *const follow_fork_mode_kind_names[] = {
407 follow_fork_mode_child,
408 follow_fork_mode_parent,
412 static const char *follow_fork_mode_string = follow_fork_mode_parent;
414 show_follow_fork_mode_string (struct ui_file *file, int from_tty,
415 struct cmd_list_element *c, const char *value)
417 fprintf_filtered (file,
418 _("Debugger response to a program "
419 "call of fork or vfork is \"%s\".\n"),
424 /* Handle changes to the inferior list based on the type of fork,
425 which process is being followed, and whether the other process
426 should be detached. On entry inferior_ptid must be the ptid of
427 the fork parent. At return inferior_ptid is the ptid of the
428 followed inferior. */
431 follow_fork_inferior (int follow_child, int detach_fork)
434 ptid_t parent_ptid, child_ptid;
436 has_vforked = (inferior_thread ()->pending_follow.kind
437 == TARGET_WAITKIND_VFORKED);
438 parent_ptid = inferior_ptid;
439 child_ptid = inferior_thread ()->pending_follow.value.related_pid;
442 && !non_stop /* Non-stop always resumes both branches. */
443 && current_ui->prompt_state == PROMPT_BLOCKED
444 && !(follow_child || detach_fork || sched_multi))
446 /* The parent stays blocked inside the vfork syscall until the
447 child execs or exits. If we don't let the child run, then
448 the parent stays blocked. If we're telling the parent to run
449 in the foreground, the user will not be able to ctrl-c to get
450 back the terminal, effectively hanging the debug session. */
451 fprintf_filtered (gdb_stderr, _("\
452 Can not resume the parent process over vfork in the foreground while\n\
453 holding the child stopped. Try \"set detach-on-fork\" or \
454 \"set schedule-multiple\".\n"));
455 /* FIXME output string > 80 columns. */
461 /* Detach new forked process? */
464 /* Before detaching from the child, remove all breakpoints
465 from it. If we forked, then this has already been taken
466 care of by infrun.c. If we vforked however, any
467 breakpoint inserted in the parent is visible in the
468 child, even those added while stopped in a vfork
469 catchpoint. This will remove the breakpoints from the
470 parent also, but they'll be reinserted below. */
473 /* Keep breakpoints list in sync. */
474 remove_breakpoints_pid (ptid_get_pid (inferior_ptid));
477 if (info_verbose || debug_infrun)
479 /* Ensure that we have a process ptid. */
480 ptid_t process_ptid = pid_to_ptid (ptid_get_pid (child_ptid));
482 target_terminal_ours_for_output ();
483 fprintf_filtered (gdb_stdlog,
484 _("Detaching after %s from child %s.\n"),
485 has_vforked ? "vfork" : "fork",
486 target_pid_to_str (process_ptid));
491 struct inferior *parent_inf, *child_inf;
493 /* Add process to GDB's tables. */
494 child_inf = add_inferior (ptid_get_pid (child_ptid));
496 parent_inf = current_inferior ();
497 child_inf->attach_flag = parent_inf->attach_flag;
498 copy_terminal_info (child_inf, parent_inf);
499 child_inf->gdbarch = parent_inf->gdbarch;
500 copy_inferior_target_desc_info (child_inf, parent_inf);
502 scoped_restore_current_pspace_and_thread restore_pspace_thread;
504 inferior_ptid = child_ptid;
505 add_thread (inferior_ptid);
506 set_current_inferior (child_inf);
507 child_inf->symfile_flags = SYMFILE_NO_READ;
509 /* If this is a vfork child, then the address-space is
510 shared with the parent. */
513 child_inf->pspace = parent_inf->pspace;
514 child_inf->aspace = parent_inf->aspace;
516 /* The parent will be frozen until the child is done
517 with the shared region. Keep track of the
519 child_inf->vfork_parent = parent_inf;
520 child_inf->pending_detach = 0;
521 parent_inf->vfork_child = child_inf;
522 parent_inf->pending_detach = 0;
526 child_inf->aspace = new_address_space ();
527 child_inf->pspace = add_program_space (child_inf->aspace);
528 child_inf->removable = 1;
529 set_current_program_space (child_inf->pspace);
530 clone_program_space (child_inf->pspace, parent_inf->pspace);
532 /* Let the shared library layer (e.g., solib-svr4) learn
533 about this new process, relocate the cloned exec, pull
534 in shared libraries, and install the solib event
535 breakpoint. If a "cloned-VM" event was propagated
536 better throughout the core, this wouldn't be
538 solib_create_inferior_hook (0);
544 struct inferior *parent_inf;
546 parent_inf = current_inferior ();
548 /* If we detached from the child, then we have to be careful
549 to not insert breakpoints in the parent until the child
550 is done with the shared memory region. However, if we're
551 staying attached to the child, then we can and should
552 insert breakpoints, so that we can debug it. A
553 subsequent child exec or exit is enough to know when does
554 the child stops using the parent's address space. */
555 parent_inf->waiting_for_vfork_done = detach_fork;
556 parent_inf->pspace->breakpoints_not_allowed = detach_fork;
561 /* Follow the child. */
562 struct inferior *parent_inf, *child_inf;
563 struct program_space *parent_pspace;
565 if (info_verbose || debug_infrun)
567 target_terminal_ours_for_output ();
568 fprintf_filtered (gdb_stdlog,
569 _("Attaching after %s %s to child %s.\n"),
570 target_pid_to_str (parent_ptid),
571 has_vforked ? "vfork" : "fork",
572 target_pid_to_str (child_ptid));
575 /* Add the new inferior first, so that the target_detach below
576 doesn't unpush the target. */
578 child_inf = add_inferior (ptid_get_pid (child_ptid));
580 parent_inf = current_inferior ();
581 child_inf->attach_flag = parent_inf->attach_flag;
582 copy_terminal_info (child_inf, parent_inf);
583 child_inf->gdbarch = parent_inf->gdbarch;
584 copy_inferior_target_desc_info (child_inf, parent_inf);
586 parent_pspace = parent_inf->pspace;
588 /* If we're vforking, we want to hold on to the parent until the
589 child exits or execs. At child exec or exit time we can
590 remove the old breakpoints from the parent and detach or
591 resume debugging it. Otherwise, detach the parent now; we'll
592 want to reuse it's program/address spaces, but we can't set
593 them to the child before removing breakpoints from the
594 parent, otherwise, the breakpoints module could decide to
595 remove breakpoints from the wrong process (since they'd be
596 assigned to the same address space). */
600 gdb_assert (child_inf->vfork_parent == NULL);
601 gdb_assert (parent_inf->vfork_child == NULL);
602 child_inf->vfork_parent = parent_inf;
603 child_inf->pending_detach = 0;
604 parent_inf->vfork_child = child_inf;
605 parent_inf->pending_detach = detach_fork;
606 parent_inf->waiting_for_vfork_done = 0;
608 else if (detach_fork)
610 if (info_verbose || debug_infrun)
612 /* Ensure that we have a process ptid. */
613 ptid_t process_ptid = pid_to_ptid (ptid_get_pid (child_ptid));
615 target_terminal_ours_for_output ();
616 fprintf_filtered (gdb_stdlog,
617 _("Detaching after fork from "
619 target_pid_to_str (process_ptid));
622 target_detach (NULL, 0);
625 /* Note that the detach above makes PARENT_INF dangling. */
627 /* Add the child thread to the appropriate lists, and switch to
628 this new thread, before cloning the program space, and
629 informing the solib layer about this new process. */
631 inferior_ptid = child_ptid;
632 add_thread (inferior_ptid);
633 set_current_inferior (child_inf);
635 /* If this is a vfork child, then the address-space is shared
636 with the parent. If we detached from the parent, then we can
637 reuse the parent's program/address spaces. */
638 if (has_vforked || detach_fork)
640 child_inf->pspace = parent_pspace;
641 child_inf->aspace = child_inf->pspace->aspace;
645 child_inf->aspace = new_address_space ();
646 child_inf->pspace = add_program_space (child_inf->aspace);
647 child_inf->removable = 1;
648 child_inf->symfile_flags = SYMFILE_NO_READ;
649 set_current_program_space (child_inf->pspace);
650 clone_program_space (child_inf->pspace, parent_pspace);
652 /* Let the shared library layer (e.g., solib-svr4) learn
653 about this new process, relocate the cloned exec, pull in
654 shared libraries, and install the solib event breakpoint.
655 If a "cloned-VM" event was propagated better throughout
656 the core, this wouldn't be required. */
657 solib_create_inferior_hook (0);
661 return target_follow_fork (follow_child, detach_fork);
664 /* Tell the target to follow the fork we're stopped at. Returns true
665 if the inferior should be resumed; false, if the target for some
666 reason decided it's best not to resume. */
671 int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
672 int should_resume = 1;
673 struct thread_info *tp;
675 /* Copy user stepping state to the new inferior thread. FIXME: the
676 followed fork child thread should have a copy of most of the
677 parent thread structure's run control related fields, not just these.
678 Initialized to avoid "may be used uninitialized" warnings from gcc. */
679 struct breakpoint *step_resume_breakpoint = NULL;
680 struct breakpoint *exception_resume_breakpoint = NULL;
681 CORE_ADDR step_range_start = 0;
682 CORE_ADDR step_range_end = 0;
683 struct frame_id step_frame_id = { 0 };
684 struct thread_fsm *thread_fsm = NULL;
689 struct target_waitstatus wait_status;
691 /* Get the last target status returned by target_wait(). */
692 get_last_target_status (&wait_ptid, &wait_status);
694 /* If not stopped at a fork event, then there's nothing else to
696 if (wait_status.kind != TARGET_WAITKIND_FORKED
697 && wait_status.kind != TARGET_WAITKIND_VFORKED)
700 /* Check if we switched over from WAIT_PTID, since the event was
702 if (!ptid_equal (wait_ptid, minus_one_ptid)
703 && !ptid_equal (inferior_ptid, wait_ptid))
705 /* We did. Switch back to WAIT_PTID thread, to tell the
706 target to follow it (in either direction). We'll
707 afterwards refuse to resume, and inform the user what
709 switch_to_thread (wait_ptid);
714 tp = inferior_thread ();
716 /* If there were any forks/vforks that were caught and are now to be
717 followed, then do so now. */
718 switch (tp->pending_follow.kind)
720 case TARGET_WAITKIND_FORKED:
721 case TARGET_WAITKIND_VFORKED:
723 ptid_t parent, child;
725 /* If the user did a next/step, etc, over a fork call,
726 preserve the stepping state in the fork child. */
727 if (follow_child && should_resume)
729 step_resume_breakpoint = clone_momentary_breakpoint
730 (tp->control.step_resume_breakpoint);
731 step_range_start = tp->control.step_range_start;
732 step_range_end = tp->control.step_range_end;
733 step_frame_id = tp->control.step_frame_id;
734 exception_resume_breakpoint
735 = clone_momentary_breakpoint (tp->control.exception_resume_breakpoint);
736 thread_fsm = tp->thread_fsm;
738 /* For now, delete the parent's sr breakpoint, otherwise,
739 parent/child sr breakpoints are considered duplicates,
740 and the child version will not be installed. Remove
741 this when the breakpoints module becomes aware of
742 inferiors and address spaces. */
743 delete_step_resume_breakpoint (tp);
744 tp->control.step_range_start = 0;
745 tp->control.step_range_end = 0;
746 tp->control.step_frame_id = null_frame_id;
747 delete_exception_resume_breakpoint (tp);
748 tp->thread_fsm = NULL;
751 parent = inferior_ptid;
752 child = tp->pending_follow.value.related_pid;
754 /* Set up inferior(s) as specified by the caller, and tell the
755 target to do whatever is necessary to follow either parent
757 if (follow_fork_inferior (follow_child, detach_fork))
759 /* Target refused to follow, or there's some other reason
760 we shouldn't resume. */
765 /* This pending follow fork event is now handled, one way
766 or another. The previous selected thread may be gone
767 from the lists by now, but if it is still around, need
768 to clear the pending follow request. */
769 tp = find_thread_ptid (parent);
771 tp->pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
773 /* This makes sure we don't try to apply the "Switched
774 over from WAIT_PID" logic above. */
775 nullify_last_target_wait_ptid ();
777 /* If we followed the child, switch to it... */
780 switch_to_thread (child);
782 /* ... and preserve the stepping state, in case the
783 user was stepping over the fork call. */
786 tp = inferior_thread ();
787 tp->control.step_resume_breakpoint
788 = step_resume_breakpoint;
789 tp->control.step_range_start = step_range_start;
790 tp->control.step_range_end = step_range_end;
791 tp->control.step_frame_id = step_frame_id;
792 tp->control.exception_resume_breakpoint
793 = exception_resume_breakpoint;
794 tp->thread_fsm = thread_fsm;
798 /* If we get here, it was because we're trying to
799 resume from a fork catchpoint, but, the user
800 has switched threads away from the thread that
801 forked. In that case, the resume command
802 issued is most likely not applicable to the
803 child, so just warn, and refuse to resume. */
804 warning (_("Not resuming: switched threads "
805 "before following fork child."));
808 /* Reset breakpoints in the child as appropriate. */
809 follow_inferior_reset_breakpoints ();
812 switch_to_thread (parent);
816 case TARGET_WAITKIND_SPURIOUS:
817 /* Nothing to follow. */
820 internal_error (__FILE__, __LINE__,
821 "Unexpected pending_follow.kind %d\n",
822 tp->pending_follow.kind);
826 return should_resume;
830 follow_inferior_reset_breakpoints (void)
832 struct thread_info *tp = inferior_thread ();
834 /* Was there a step_resume breakpoint? (There was if the user
835 did a "next" at the fork() call.) If so, explicitly reset its
836 thread number. Cloned step_resume breakpoints are disabled on
837 creation, so enable it here now that it is associated with the
840 step_resumes are a form of bp that are made to be per-thread.
841 Since we created the step_resume bp when the parent process
842 was being debugged, and now are switching to the child process,
843 from the breakpoint package's viewpoint, that's a switch of
844 "threads". We must update the bp's notion of which thread
845 it is for, or it'll be ignored when it triggers. */
847 if (tp->control.step_resume_breakpoint)
849 breakpoint_re_set_thread (tp->control.step_resume_breakpoint);
850 tp->control.step_resume_breakpoint->loc->enabled = 1;
853 /* Treat exception_resume breakpoints like step_resume breakpoints. */
854 if (tp->control.exception_resume_breakpoint)
856 breakpoint_re_set_thread (tp->control.exception_resume_breakpoint);
857 tp->control.exception_resume_breakpoint->loc->enabled = 1;
860 /* Reinsert all breakpoints in the child. The user may have set
861 breakpoints after catching the fork, in which case those
862 were never set in the child, but only in the parent. This makes
863 sure the inserted breakpoints match the breakpoint list. */
865 breakpoint_re_set ();
866 insert_breakpoints ();
869 /* The child has exited or execed: resume threads of the parent the
870 user wanted to be executing. */
873 proceed_after_vfork_done (struct thread_info *thread,
876 int pid = * (int *) arg;
878 if (ptid_get_pid (thread->ptid) == pid
879 && is_running (thread->ptid)
880 && !is_executing (thread->ptid)
881 && !thread->stop_requested
882 && thread->suspend.stop_signal == GDB_SIGNAL_0)
885 fprintf_unfiltered (gdb_stdlog,
886 "infrun: resuming vfork parent thread %s\n",
887 target_pid_to_str (thread->ptid));
889 switch_to_thread (thread->ptid);
890 clear_proceed_status (0);
891 proceed ((CORE_ADDR) -1, GDB_SIGNAL_DEFAULT);
897 /* Save/restore inferior_ptid, current program space and current
898 inferior. Only use this if the current context points at an exited
899 inferior (and therefore there's no current thread to save). */
900 class scoped_restore_exited_inferior
903 scoped_restore_exited_inferior ()
904 : m_saved_ptid (&inferior_ptid)
908 scoped_restore_tmpl<ptid_t> m_saved_ptid;
909 scoped_restore_current_program_space m_pspace;
910 scoped_restore_current_inferior m_inferior;
913 /* Called whenever we notice an exec or exit event, to handle
914 detaching or resuming a vfork parent. */
917 handle_vfork_child_exec_or_exit (int exec)
919 struct inferior *inf = current_inferior ();
921 if (inf->vfork_parent)
923 int resume_parent = -1;
925 /* This exec or exit marks the end of the shared memory region
926 between the parent and the child. If the user wanted to
927 detach from the parent, now is the time. */
929 if (inf->vfork_parent->pending_detach)
931 struct thread_info *tp;
932 struct program_space *pspace;
933 struct address_space *aspace;
935 /* follow-fork child, detach-on-fork on. */
937 inf->vfork_parent->pending_detach = 0;
939 gdb::optional<scoped_restore_exited_inferior>
940 maybe_restore_inferior;
941 gdb::optional<scoped_restore_current_pspace_and_thread>
942 maybe_restore_thread;
944 /* If we're handling a child exit, then inferior_ptid points
945 at the inferior's pid, not to a thread. */
947 maybe_restore_inferior.emplace ();
949 maybe_restore_thread.emplace ();
951 /* We're letting loose of the parent. */
952 tp = any_live_thread_of_process (inf->vfork_parent->pid);
953 switch_to_thread (tp->ptid);
955 /* We're about to detach from the parent, which implicitly
956 removes breakpoints from its address space. There's a
957 catch here: we want to reuse the spaces for the child,
958 but, parent/child are still sharing the pspace at this
959 point, although the exec in reality makes the kernel give
960 the child a fresh set of new pages. The problem here is
961 that the breakpoints module being unaware of this, would
962 likely chose the child process to write to the parent
963 address space. Swapping the child temporarily away from
964 the spaces has the desired effect. Yes, this is "sort
967 pspace = inf->pspace;
968 aspace = inf->aspace;
972 if (debug_infrun || info_verbose)
974 target_terminal_ours_for_output ();
978 fprintf_filtered (gdb_stdlog,
979 _("Detaching vfork parent process "
980 "%d after child exec.\n"),
981 inf->vfork_parent->pid);
985 fprintf_filtered (gdb_stdlog,
986 _("Detaching vfork parent process "
987 "%d after child exit.\n"),
988 inf->vfork_parent->pid);
992 target_detach (NULL, 0);
995 inf->pspace = pspace;
996 inf->aspace = aspace;
1000 /* We're staying attached to the parent, so, really give the
1001 child a new address space. */
1002 inf->pspace = add_program_space (maybe_new_address_space ());
1003 inf->aspace = inf->pspace->aspace;
1005 set_current_program_space (inf->pspace);
1007 resume_parent = inf->vfork_parent->pid;
1009 /* Break the bonds. */
1010 inf->vfork_parent->vfork_child = NULL;
1014 struct program_space *pspace;
1016 /* If this is a vfork child exiting, then the pspace and
1017 aspaces were shared with the parent. Since we're
1018 reporting the process exit, we'll be mourning all that is
1019 found in the address space, and switching to null_ptid,
1020 preparing to start a new inferior. But, since we don't
1021 want to clobber the parent's address/program spaces, we
1022 go ahead and create a new one for this exiting
1025 /* Switch to null_ptid while running clone_program_space, so
1026 that clone_program_space doesn't want to read the
1027 selected frame of a dead process. */
1028 scoped_restore restore_ptid
1029 = make_scoped_restore (&inferior_ptid, null_ptid);
1031 /* This inferior is dead, so avoid giving the breakpoints
1032 module the option to write through to it (cloning a
1033 program space resets breakpoints). */
1036 pspace = add_program_space (maybe_new_address_space ());
1037 set_current_program_space (pspace);
1039 inf->symfile_flags = SYMFILE_NO_READ;
1040 clone_program_space (pspace, inf->vfork_parent->pspace);
1041 inf->pspace = pspace;
1042 inf->aspace = pspace->aspace;
1044 resume_parent = inf->vfork_parent->pid;
1045 /* Break the bonds. */
1046 inf->vfork_parent->vfork_child = NULL;
1049 inf->vfork_parent = NULL;
1051 gdb_assert (current_program_space == inf->pspace);
1053 if (non_stop && resume_parent != -1)
1055 /* If the user wanted the parent to be running, let it go
1057 scoped_restore_current_thread restore_thread;
1060 fprintf_unfiltered (gdb_stdlog,
1061 "infrun: resuming vfork parent process %d\n",
1064 iterate_over_threads (proceed_after_vfork_done, &resume_parent);
1069 /* Enum strings for "set|show follow-exec-mode". */
1071 static const char follow_exec_mode_new[] = "new";
1072 static const char follow_exec_mode_same[] = "same";
1073 static const char *const follow_exec_mode_names[] =
1075 follow_exec_mode_new,
1076 follow_exec_mode_same,
1080 static const char *follow_exec_mode_string = follow_exec_mode_same;
1082 show_follow_exec_mode_string (struct ui_file *file, int from_tty,
1083 struct cmd_list_element *c, const char *value)
1085 fprintf_filtered (file, _("Follow exec mode is \"%s\".\n"), value);
1088 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1091 follow_exec (ptid_t ptid, char *exec_file_target)
1093 struct thread_info *th, *tmp;
1094 struct inferior *inf = current_inferior ();
1095 int pid = ptid_get_pid (ptid);
1096 ptid_t process_ptid;
1097 char *exec_file_host;
1098 struct cleanup *old_chain;
1100 /* This is an exec event that we actually wish to pay attention to.
1101 Refresh our symbol table to the newly exec'd program, remove any
1102 momentary bp's, etc.
1104 If there are breakpoints, they aren't really inserted now,
1105 since the exec() transformed our inferior into a fresh set
1108 We want to preserve symbolic breakpoints on the list, since
1109 we have hopes that they can be reset after the new a.out's
1110 symbol table is read.
1112 However, any "raw" breakpoints must be removed from the list
1113 (e.g., the solib bp's), since their address is probably invalid
1116 And, we DON'T want to call delete_breakpoints() here, since
1117 that may write the bp's "shadow contents" (the instruction
1118 value that was overwritten witha TRAP instruction). Since
1119 we now have a new a.out, those shadow contents aren't valid. */
1121 mark_breakpoints_out ();
1123 /* The target reports the exec event to the main thread, even if
1124 some other thread does the exec, and even if the main thread was
1125 stopped or already gone. We may still have non-leader threads of
1126 the process on our list. E.g., on targets that don't have thread
1127 exit events (like remote); or on native Linux in non-stop mode if
1128 there were only two threads in the inferior and the non-leader
1129 one is the one that execs (and nothing forces an update of the
1130 thread list up to here). When debugging remotely, it's best to
1131 avoid extra traffic, when possible, so avoid syncing the thread
1132 list with the target, and instead go ahead and delete all threads
1133 of the process but one that reported the event. Note this must
1134 be done before calling update_breakpoints_after_exec, as
1135 otherwise clearing the threads' resources would reference stale
1136 thread breakpoints -- it may have been one of these threads that
1137 stepped across the exec. We could just clear their stepping
1138 states, but as long as we're iterating, might as well delete
1139 them. Deleting them now rather than at the next user-visible
1140 stop provides a nicer sequence of events for user and MI
1142 ALL_THREADS_SAFE (th, tmp)
1143 if (ptid_get_pid (th->ptid) == pid && !ptid_equal (th->ptid, ptid))
1144 delete_thread (th->ptid);
1146 /* We also need to clear any left over stale state for the
1147 leader/event thread. E.g., if there was any step-resume
1148 breakpoint or similar, it's gone now. We cannot truly
1149 step-to-next statement through an exec(). */
1150 th = inferior_thread ();
1151 th->control.step_resume_breakpoint = NULL;
1152 th->control.exception_resume_breakpoint = NULL;
1153 th->control.single_step_breakpoints = NULL;
1154 th->control.step_range_start = 0;
1155 th->control.step_range_end = 0;
1157 /* The user may have had the main thread held stopped in the
1158 previous image (e.g., schedlock on, or non-stop). Release
1160 th->stop_requested = 0;
1162 update_breakpoints_after_exec ();
1164 /* What is this a.out's name? */
1165 process_ptid = pid_to_ptid (pid);
1166 printf_unfiltered (_("%s is executing new program: %s\n"),
1167 target_pid_to_str (process_ptid),
1170 /* We've followed the inferior through an exec. Therefore, the
1171 inferior has essentially been killed & reborn. */
1173 gdb_flush (gdb_stdout);
1175 breakpoint_init_inferior (inf_execd);
1177 exec_file_host = exec_file_find (exec_file_target, NULL);
1178 old_chain = make_cleanup (xfree, exec_file_host);
1180 /* If we were unable to map the executable target pathname onto a host
1181 pathname, tell the user that. Otherwise GDB's subsequent behavior
1182 is confusing. Maybe it would even be better to stop at this point
1183 so that the user can specify a file manually before continuing. */
1184 if (exec_file_host == NULL)
1185 warning (_("Could not load symbols for executable %s.\n"
1186 "Do you need \"set sysroot\"?"),
1189 /* Reset the shared library package. This ensures that we get a
1190 shlib event when the child reaches "_start", at which point the
1191 dld will have had a chance to initialize the child. */
1192 /* Also, loading a symbol file below may trigger symbol lookups, and
1193 we don't want those to be satisfied by the libraries of the
1194 previous incarnation of this process. */
1195 no_shared_libraries (NULL, 0);
1197 if (follow_exec_mode_string == follow_exec_mode_new)
1199 /* The user wants to keep the old inferior and program spaces
1200 around. Create a new fresh one, and switch to it. */
1202 /* Do exit processing for the original inferior before adding
1203 the new inferior so we don't have two active inferiors with
1204 the same ptid, which can confuse find_inferior_ptid. */
1205 exit_inferior_num_silent (current_inferior ()->num);
1207 inf = add_inferior_with_spaces ();
1209 target_follow_exec (inf, exec_file_target);
1211 set_current_inferior (inf);
1212 set_current_program_space (inf->pspace);
1217 /* The old description may no longer be fit for the new image.
1218 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1219 old description; we'll read a new one below. No need to do
1220 this on "follow-exec-mode new", as the old inferior stays
1221 around (its description is later cleared/refetched on
1223 target_clear_description ();
1226 gdb_assert (current_program_space == inf->pspace);
1228 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1229 because the proper displacement for a PIE (Position Independent
1230 Executable) main symbol file will only be computed by
1231 solib_create_inferior_hook below. breakpoint_re_set would fail
1232 to insert the breakpoints with the zero displacement. */
1233 try_open_exec_file (exec_file_host, inf, SYMFILE_DEFER_BP_RESET);
1235 do_cleanups (old_chain);
1237 /* If the target can specify a description, read it. Must do this
1238 after flipping to the new executable (because the target supplied
1239 description must be compatible with the executable's
1240 architecture, and the old executable may e.g., be 32-bit, while
1241 the new one 64-bit), and before anything involving memory or
1243 target_find_description ();
1245 solib_create_inferior_hook (0);
1247 jit_inferior_created_hook ();
1249 breakpoint_re_set ();
1251 /* Reinsert all breakpoints. (Those which were symbolic have
1252 been reset to the proper address in the new a.out, thanks
1253 to symbol_file_command...). */
1254 insert_breakpoints ();
1256 /* The next resume of this inferior should bring it to the shlib
1257 startup breakpoints. (If the user had also set bp's on
1258 "main" from the old (parent) process, then they'll auto-
1259 matically get reset there in the new process.). */
1262 /* The queue of threads that need to do a step-over operation to get
1263 past e.g., a breakpoint. What technique is used to step over the
1264 breakpoint/watchpoint does not matter -- all threads end up in the
1265 same queue, to maintain rough temporal order of execution, in order
1266 to avoid starvation, otherwise, we could e.g., find ourselves
1267 constantly stepping the same couple threads past their breakpoints
1268 over and over, if the single-step finish fast enough. */
1269 struct thread_info *step_over_queue_head;
1271 /* Bit flags indicating what the thread needs to step over. */
1273 enum step_over_what_flag
1275 /* Step over a breakpoint. */
1276 STEP_OVER_BREAKPOINT = 1,
1278 /* Step past a non-continuable watchpoint, in order to let the
1279 instruction execute so we can evaluate the watchpoint
1281 STEP_OVER_WATCHPOINT = 2
1283 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag, step_over_what);
1285 /* Info about an instruction that is being stepped over. */
1287 struct step_over_info
1289 /* If we're stepping past a breakpoint, this is the address space
1290 and address of the instruction the breakpoint is set at. We'll
1291 skip inserting all breakpoints here. Valid iff ASPACE is
1293 struct address_space *aspace;
1296 /* The instruction being stepped over triggers a nonsteppable
1297 watchpoint. If true, we'll skip inserting watchpoints. */
1298 int nonsteppable_watchpoint_p;
1300 /* The thread's global number. */
1304 /* The step-over info of the location that is being stepped over.
1306 Note that with async/breakpoint always-inserted mode, a user might
1307 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1308 being stepped over. As setting a new breakpoint inserts all
1309 breakpoints, we need to make sure the breakpoint being stepped over
1310 isn't inserted then. We do that by only clearing the step-over
1311 info when the step-over is actually finished (or aborted).
1313 Presently GDB can only step over one breakpoint at any given time.
1314 Given threads that can't run code in the same address space as the
1315 breakpoint's can't really miss the breakpoint, GDB could be taught
1316 to step-over at most one breakpoint per address space (so this info
1317 could move to the address space object if/when GDB is extended).
1318 The set of breakpoints being stepped over will normally be much
1319 smaller than the set of all breakpoints, so a flag in the
1320 breakpoint location structure would be wasteful. A separate list
1321 also saves complexity and run-time, as otherwise we'd have to go
1322 through all breakpoint locations clearing their flag whenever we
1323 start a new sequence. Similar considerations weigh against storing
1324 this info in the thread object. Plus, not all step overs actually
1325 have breakpoint locations -- e.g., stepping past a single-step
1326 breakpoint, or stepping to complete a non-continuable
1328 static struct step_over_info step_over_info;
1330 /* Record the address of the breakpoint/instruction we're currently
1332 N.B. We record the aspace and address now, instead of say just the thread,
1333 because when we need the info later the thread may be running. */
1336 set_step_over_info (struct address_space *aspace, CORE_ADDR address,
1337 int nonsteppable_watchpoint_p,
1340 step_over_info.aspace = aspace;
1341 step_over_info.address = address;
1342 step_over_info.nonsteppable_watchpoint_p = nonsteppable_watchpoint_p;
1343 step_over_info.thread = thread;
1346 /* Called when we're not longer stepping over a breakpoint / an
1347 instruction, so all breakpoints are free to be (re)inserted. */
1350 clear_step_over_info (void)
1353 fprintf_unfiltered (gdb_stdlog,
1354 "infrun: clear_step_over_info\n");
1355 step_over_info.aspace = NULL;
1356 step_over_info.address = 0;
1357 step_over_info.nonsteppable_watchpoint_p = 0;
1358 step_over_info.thread = -1;
1364 stepping_past_instruction_at (struct address_space *aspace,
1367 return (step_over_info.aspace != NULL
1368 && breakpoint_address_match (aspace, address,
1369 step_over_info.aspace,
1370 step_over_info.address));
1376 thread_is_stepping_over_breakpoint (int thread)
1378 return (step_over_info.thread != -1
1379 && thread == step_over_info.thread);
1385 stepping_past_nonsteppable_watchpoint (void)
1387 return step_over_info.nonsteppable_watchpoint_p;
1390 /* Returns true if step-over info is valid. */
1393 step_over_info_valid_p (void)
1395 return (step_over_info.aspace != NULL
1396 || stepping_past_nonsteppable_watchpoint ());
1400 /* Displaced stepping. */
1402 /* In non-stop debugging mode, we must take special care to manage
1403 breakpoints properly; in particular, the traditional strategy for
1404 stepping a thread past a breakpoint it has hit is unsuitable.
1405 'Displaced stepping' is a tactic for stepping one thread past a
1406 breakpoint it has hit while ensuring that other threads running
1407 concurrently will hit the breakpoint as they should.
1409 The traditional way to step a thread T off a breakpoint in a
1410 multi-threaded program in all-stop mode is as follows:
1412 a0) Initially, all threads are stopped, and breakpoints are not
1414 a1) We single-step T, leaving breakpoints uninserted.
1415 a2) We insert breakpoints, and resume all threads.
1417 In non-stop debugging, however, this strategy is unsuitable: we
1418 don't want to have to stop all threads in the system in order to
1419 continue or step T past a breakpoint. Instead, we use displaced
1422 n0) Initially, T is stopped, other threads are running, and
1423 breakpoints are inserted.
1424 n1) We copy the instruction "under" the breakpoint to a separate
1425 location, outside the main code stream, making any adjustments
1426 to the instruction, register, and memory state as directed by
1428 n2) We single-step T over the instruction at its new location.
1429 n3) We adjust the resulting register and memory state as directed
1430 by T's architecture. This includes resetting T's PC to point
1431 back into the main instruction stream.
1434 This approach depends on the following gdbarch methods:
1436 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1437 indicate where to copy the instruction, and how much space must
1438 be reserved there. We use these in step n1.
1440 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1441 address, and makes any necessary adjustments to the instruction,
1442 register contents, and memory. We use this in step n1.
1444 - gdbarch_displaced_step_fixup adjusts registers and memory after
1445 we have successfuly single-stepped the instruction, to yield the
1446 same effect the instruction would have had if we had executed it
1447 at its original address. We use this in step n3.
1449 - gdbarch_displaced_step_free_closure provides cleanup.
1451 The gdbarch_displaced_step_copy_insn and
1452 gdbarch_displaced_step_fixup functions must be written so that
1453 copying an instruction with gdbarch_displaced_step_copy_insn,
1454 single-stepping across the copied instruction, and then applying
1455 gdbarch_displaced_insn_fixup should have the same effects on the
1456 thread's memory and registers as stepping the instruction in place
1457 would have. Exactly which responsibilities fall to the copy and
1458 which fall to the fixup is up to the author of those functions.
1460 See the comments in gdbarch.sh for details.
1462 Note that displaced stepping and software single-step cannot
1463 currently be used in combination, although with some care I think
1464 they could be made to. Software single-step works by placing
1465 breakpoints on all possible subsequent instructions; if the
1466 displaced instruction is a PC-relative jump, those breakpoints
1467 could fall in very strange places --- on pages that aren't
1468 executable, or at addresses that are not proper instruction
1469 boundaries. (We do generally let other threads run while we wait
1470 to hit the software single-step breakpoint, and they might
1471 encounter such a corrupted instruction.) One way to work around
1472 this would be to have gdbarch_displaced_step_copy_insn fully
1473 simulate the effect of PC-relative instructions (and return NULL)
1474 on architectures that use software single-stepping.
1476 In non-stop mode, we can have independent and simultaneous step
1477 requests, so more than one thread may need to simultaneously step
1478 over a breakpoint. The current implementation assumes there is
1479 only one scratch space per process. In this case, we have to
1480 serialize access to the scratch space. If thread A wants to step
1481 over a breakpoint, but we are currently waiting for some other
1482 thread to complete a displaced step, we leave thread A stopped and
1483 place it in the displaced_step_request_queue. Whenever a displaced
1484 step finishes, we pick the next thread in the queue and start a new
1485 displaced step operation on it. See displaced_step_prepare and
1486 displaced_step_fixup for details. */
1488 /* Per-inferior displaced stepping state. */
1489 struct displaced_step_inferior_state
1491 /* Pointer to next in linked list. */
1492 struct displaced_step_inferior_state *next;
1494 /* The process this displaced step state refers to. */
1497 /* True if preparing a displaced step ever failed. If so, we won't
1498 try displaced stepping for this inferior again. */
1501 /* If this is not null_ptid, this is the thread carrying out a
1502 displaced single-step in process PID. This thread's state will
1503 require fixing up once it has completed its step. */
1506 /* The architecture the thread had when we stepped it. */
1507 struct gdbarch *step_gdbarch;
1509 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1510 for post-step cleanup. */
1511 struct displaced_step_closure *step_closure;
1513 /* The address of the original instruction, and the copy we
1515 CORE_ADDR step_original, step_copy;
1517 /* Saved contents of copy area. */
1518 gdb_byte *step_saved_copy;
1521 /* The list of states of processes involved in displaced stepping
1523 static struct displaced_step_inferior_state *displaced_step_inferior_states;
1525 /* Get the displaced stepping state of process PID. */
1527 static struct displaced_step_inferior_state *
1528 get_displaced_stepping_state (int pid)
1530 struct displaced_step_inferior_state *state;
1532 for (state = displaced_step_inferior_states;
1534 state = state->next)
1535 if (state->pid == pid)
1541 /* Returns true if any inferior has a thread doing a displaced
1545 displaced_step_in_progress_any_inferior (void)
1547 struct displaced_step_inferior_state *state;
1549 for (state = displaced_step_inferior_states;
1551 state = state->next)
1552 if (!ptid_equal (state->step_ptid, null_ptid))
1558 /* Return true if thread represented by PTID is doing a displaced
1562 displaced_step_in_progress_thread (ptid_t ptid)
1564 struct displaced_step_inferior_state *displaced;
1566 gdb_assert (!ptid_equal (ptid, null_ptid));
1568 displaced = get_displaced_stepping_state (ptid_get_pid (ptid));
1570 return (displaced != NULL && ptid_equal (displaced->step_ptid, ptid));
1573 /* Return true if process PID has a thread doing a displaced step. */
1576 displaced_step_in_progress (int pid)
1578 struct displaced_step_inferior_state *displaced;
1580 displaced = get_displaced_stepping_state (pid);
1581 if (displaced != NULL && !ptid_equal (displaced->step_ptid, null_ptid))
1587 /* Add a new displaced stepping state for process PID to the displaced
1588 stepping state list, or return a pointer to an already existing
1589 entry, if it already exists. Never returns NULL. */
1591 static struct displaced_step_inferior_state *
1592 add_displaced_stepping_state (int pid)
1594 struct displaced_step_inferior_state *state;
1596 for (state = displaced_step_inferior_states;
1598 state = state->next)
1599 if (state->pid == pid)
1602 state = XCNEW (struct displaced_step_inferior_state);
1604 state->next = displaced_step_inferior_states;
1605 displaced_step_inferior_states = state;
1610 /* If inferior is in displaced stepping, and ADDR equals to starting address
1611 of copy area, return corresponding displaced_step_closure. Otherwise,
1614 struct displaced_step_closure*
1615 get_displaced_step_closure_by_addr (CORE_ADDR addr)
1617 struct displaced_step_inferior_state *displaced
1618 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
1620 /* If checking the mode of displaced instruction in copy area. */
1621 if (displaced && !ptid_equal (displaced->step_ptid, null_ptid)
1622 && (displaced->step_copy == addr))
1623 return displaced->step_closure;
1628 /* Remove the displaced stepping state of process PID. */
1631 remove_displaced_stepping_state (int pid)
1633 struct displaced_step_inferior_state *it, **prev_next_p;
1635 gdb_assert (pid != 0);
1637 it = displaced_step_inferior_states;
1638 prev_next_p = &displaced_step_inferior_states;
1643 *prev_next_p = it->next;
1648 prev_next_p = &it->next;
1654 infrun_inferior_exit (struct inferior *inf)
1656 remove_displaced_stepping_state (inf->pid);
1659 /* If ON, and the architecture supports it, GDB will use displaced
1660 stepping to step over breakpoints. If OFF, or if the architecture
1661 doesn't support it, GDB will instead use the traditional
1662 hold-and-step approach. If AUTO (which is the default), GDB will
1663 decide which technique to use to step over breakpoints depending on
1664 which of all-stop or non-stop mode is active --- displaced stepping
1665 in non-stop mode; hold-and-step in all-stop mode. */
1667 static enum auto_boolean can_use_displaced_stepping = AUTO_BOOLEAN_AUTO;
1670 show_can_use_displaced_stepping (struct ui_file *file, int from_tty,
1671 struct cmd_list_element *c,
1674 if (can_use_displaced_stepping == AUTO_BOOLEAN_AUTO)
1675 fprintf_filtered (file,
1676 _("Debugger's willingness to use displaced stepping "
1677 "to step over breakpoints is %s (currently %s).\n"),
1678 value, target_is_non_stop_p () ? "on" : "off");
1680 fprintf_filtered (file,
1681 _("Debugger's willingness to use displaced stepping "
1682 "to step over breakpoints is %s.\n"), value);
1685 /* Return non-zero if displaced stepping can/should be used to step
1686 over breakpoints of thread TP. */
1689 use_displaced_stepping (struct thread_info *tp)
1691 struct regcache *regcache = get_thread_regcache (tp->ptid);
1692 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1693 struct displaced_step_inferior_state *displaced_state;
1695 displaced_state = get_displaced_stepping_state (ptid_get_pid (tp->ptid));
1697 return (((can_use_displaced_stepping == AUTO_BOOLEAN_AUTO
1698 && target_is_non_stop_p ())
1699 || can_use_displaced_stepping == AUTO_BOOLEAN_TRUE)
1700 && gdbarch_displaced_step_copy_insn_p (gdbarch)
1701 && find_record_target () == NULL
1702 && (displaced_state == NULL
1703 || !displaced_state->failed_before));
1706 /* Clean out any stray displaced stepping state. */
1708 displaced_step_clear (struct displaced_step_inferior_state *displaced)
1710 /* Indicate that there is no cleanup pending. */
1711 displaced->step_ptid = null_ptid;
1713 if (displaced->step_closure)
1715 gdbarch_displaced_step_free_closure (displaced->step_gdbarch,
1716 displaced->step_closure);
1717 displaced->step_closure = NULL;
1722 displaced_step_clear_cleanup (void *arg)
1724 struct displaced_step_inferior_state *state
1725 = (struct displaced_step_inferior_state *) arg;
1727 displaced_step_clear (state);
1730 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1732 displaced_step_dump_bytes (struct ui_file *file,
1733 const gdb_byte *buf,
1738 for (i = 0; i < len; i++)
1739 fprintf_unfiltered (file, "%02x ", buf[i]);
1740 fputs_unfiltered ("\n", file);
1743 /* Prepare to single-step, using displaced stepping.
1745 Note that we cannot use displaced stepping when we have a signal to
1746 deliver. If we have a signal to deliver and an instruction to step
1747 over, then after the step, there will be no indication from the
1748 target whether the thread entered a signal handler or ignored the
1749 signal and stepped over the instruction successfully --- both cases
1750 result in a simple SIGTRAP. In the first case we mustn't do a
1751 fixup, and in the second case we must --- but we can't tell which.
1752 Comments in the code for 'random signals' in handle_inferior_event
1753 explain how we handle this case instead.
1755 Returns 1 if preparing was successful -- this thread is going to be
1756 stepped now; 0 if displaced stepping this thread got queued; or -1
1757 if this instruction can't be displaced stepped. */
1760 displaced_step_prepare_throw (ptid_t ptid)
1762 struct cleanup *old_cleanups, *ignore_cleanups;
1763 struct thread_info *tp = find_thread_ptid (ptid);
1764 struct regcache *regcache = get_thread_regcache (ptid);
1765 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1766 struct address_space *aspace = get_regcache_aspace (regcache);
1767 CORE_ADDR original, copy;
1769 struct displaced_step_closure *closure;
1770 struct displaced_step_inferior_state *displaced;
1773 /* We should never reach this function if the architecture does not
1774 support displaced stepping. */
1775 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch));
1777 /* Nor if the thread isn't meant to step over a breakpoint. */
1778 gdb_assert (tp->control.trap_expected);
1780 /* Disable range stepping while executing in the scratch pad. We
1781 want a single-step even if executing the displaced instruction in
1782 the scratch buffer lands within the stepping range (e.g., a
1784 tp->control.may_range_step = 0;
1786 /* We have to displaced step one thread at a time, as we only have
1787 access to a single scratch space per inferior. */
1789 displaced = add_displaced_stepping_state (ptid_get_pid (ptid));
1791 if (!ptid_equal (displaced->step_ptid, null_ptid))
1793 /* Already waiting for a displaced step to finish. Defer this
1794 request and place in queue. */
1796 if (debug_displaced)
1797 fprintf_unfiltered (gdb_stdlog,
1798 "displaced: deferring step of %s\n",
1799 target_pid_to_str (ptid));
1801 thread_step_over_chain_enqueue (tp);
1806 if (debug_displaced)
1807 fprintf_unfiltered (gdb_stdlog,
1808 "displaced: stepping %s now\n",
1809 target_pid_to_str (ptid));
1812 displaced_step_clear (displaced);
1814 old_cleanups = save_inferior_ptid ();
1815 inferior_ptid = ptid;
1817 original = regcache_read_pc (regcache);
1819 copy = gdbarch_displaced_step_location (gdbarch);
1820 len = gdbarch_max_insn_length (gdbarch);
1822 if (breakpoint_in_range_p (aspace, copy, len))
1824 /* There's a breakpoint set in the scratch pad location range
1825 (which is usually around the entry point). We'd either
1826 install it before resuming, which would overwrite/corrupt the
1827 scratch pad, or if it was already inserted, this displaced
1828 step would overwrite it. The latter is OK in the sense that
1829 we already assume that no thread is going to execute the code
1830 in the scratch pad range (after initial startup) anyway, but
1831 the former is unacceptable. Simply punt and fallback to
1832 stepping over this breakpoint in-line. */
1833 if (debug_displaced)
1835 fprintf_unfiltered (gdb_stdlog,
1836 "displaced: breakpoint set in scratch pad. "
1837 "Stepping over breakpoint in-line instead.\n");
1840 do_cleanups (old_cleanups);
1844 /* Save the original contents of the copy area. */
1845 displaced->step_saved_copy = (gdb_byte *) xmalloc (len);
1846 ignore_cleanups = make_cleanup (free_current_contents,
1847 &displaced->step_saved_copy);
1848 status = target_read_memory (copy, displaced->step_saved_copy, len);
1850 throw_error (MEMORY_ERROR,
1851 _("Error accessing memory address %s (%s) for "
1852 "displaced-stepping scratch space."),
1853 paddress (gdbarch, copy), safe_strerror (status));
1854 if (debug_displaced)
1856 fprintf_unfiltered (gdb_stdlog, "displaced: saved %s: ",
1857 paddress (gdbarch, copy));
1858 displaced_step_dump_bytes (gdb_stdlog,
1859 displaced->step_saved_copy,
1863 closure = gdbarch_displaced_step_copy_insn (gdbarch,
1864 original, copy, regcache);
1865 if (closure == NULL)
1867 /* The architecture doesn't know how or want to displaced step
1868 this instruction or instruction sequence. Fallback to
1869 stepping over the breakpoint in-line. */
1870 do_cleanups (old_cleanups);
1874 /* Save the information we need to fix things up if the step
1876 displaced->step_ptid = ptid;
1877 displaced->step_gdbarch = gdbarch;
1878 displaced->step_closure = closure;
1879 displaced->step_original = original;
1880 displaced->step_copy = copy;
1882 make_cleanup (displaced_step_clear_cleanup, displaced);
1884 /* Resume execution at the copy. */
1885 regcache_write_pc (regcache, copy);
1887 discard_cleanups (ignore_cleanups);
1889 do_cleanups (old_cleanups);
1891 if (debug_displaced)
1892 fprintf_unfiltered (gdb_stdlog, "displaced: displaced pc to %s\n",
1893 paddress (gdbarch, copy));
1898 /* Wrapper for displaced_step_prepare_throw that disabled further
1899 attempts at displaced stepping if we get a memory error. */
1902 displaced_step_prepare (ptid_t ptid)
1908 prepared = displaced_step_prepare_throw (ptid);
1910 CATCH (ex, RETURN_MASK_ERROR)
1912 struct displaced_step_inferior_state *displaced_state;
1914 if (ex.error != MEMORY_ERROR
1915 && ex.error != NOT_SUPPORTED_ERROR)
1916 throw_exception (ex);
1920 fprintf_unfiltered (gdb_stdlog,
1921 "infrun: disabling displaced stepping: %s\n",
1925 /* Be verbose if "set displaced-stepping" is "on", silent if
1927 if (can_use_displaced_stepping == AUTO_BOOLEAN_TRUE)
1929 warning (_("disabling displaced stepping: %s"),
1933 /* Disable further displaced stepping attempts. */
1935 = get_displaced_stepping_state (ptid_get_pid (ptid));
1936 displaced_state->failed_before = 1;
1944 write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr,
1945 const gdb_byte *myaddr, int len)
1947 struct cleanup *ptid_cleanup = save_inferior_ptid ();
1949 inferior_ptid = ptid;
1950 write_memory (memaddr, myaddr, len);
1951 do_cleanups (ptid_cleanup);
1954 /* Restore the contents of the copy area for thread PTID. */
1957 displaced_step_restore (struct displaced_step_inferior_state *displaced,
1960 ULONGEST len = gdbarch_max_insn_length (displaced->step_gdbarch);
1962 write_memory_ptid (ptid, displaced->step_copy,
1963 displaced->step_saved_copy, len);
1964 if (debug_displaced)
1965 fprintf_unfiltered (gdb_stdlog, "displaced: restored %s %s\n",
1966 target_pid_to_str (ptid),
1967 paddress (displaced->step_gdbarch,
1968 displaced->step_copy));
1971 /* If we displaced stepped an instruction successfully, adjust
1972 registers and memory to yield the same effect the instruction would
1973 have had if we had executed it at its original address, and return
1974 1. If the instruction didn't complete, relocate the PC and return
1975 -1. If the thread wasn't displaced stepping, return 0. */
1978 displaced_step_fixup (ptid_t event_ptid, enum gdb_signal signal)
1980 struct cleanup *old_cleanups;
1981 struct displaced_step_inferior_state *displaced
1982 = get_displaced_stepping_state (ptid_get_pid (event_ptid));
1985 /* Was any thread of this process doing a displaced step? */
1986 if (displaced == NULL)
1989 /* Was this event for the pid we displaced? */
1990 if (ptid_equal (displaced->step_ptid, null_ptid)
1991 || ! ptid_equal (displaced->step_ptid, event_ptid))
1994 old_cleanups = make_cleanup (displaced_step_clear_cleanup, displaced);
1996 displaced_step_restore (displaced, displaced->step_ptid);
1998 /* Fixup may need to read memory/registers. Switch to the thread
1999 that we're fixing up. Also, target_stopped_by_watchpoint checks
2000 the current thread. */
2001 switch_to_thread (event_ptid);
2003 /* Did the instruction complete successfully? */
2004 if (signal == GDB_SIGNAL_TRAP
2005 && !(target_stopped_by_watchpoint ()
2006 && (gdbarch_have_nonsteppable_watchpoint (displaced->step_gdbarch)
2007 || target_have_steppable_watchpoint)))
2009 /* Fix up the resulting state. */
2010 gdbarch_displaced_step_fixup (displaced->step_gdbarch,
2011 displaced->step_closure,
2012 displaced->step_original,
2013 displaced->step_copy,
2014 get_thread_regcache (displaced->step_ptid));
2019 /* Since the instruction didn't complete, all we can do is
2021 struct regcache *regcache = get_thread_regcache (event_ptid);
2022 CORE_ADDR pc = regcache_read_pc (regcache);
2024 pc = displaced->step_original + (pc - displaced->step_copy);
2025 regcache_write_pc (regcache, pc);
2029 do_cleanups (old_cleanups);
2031 displaced->step_ptid = null_ptid;
2036 /* Data to be passed around while handling an event. This data is
2037 discarded between events. */
2038 struct execution_control_state
2041 /* The thread that got the event, if this was a thread event; NULL
2043 struct thread_info *event_thread;
2045 struct target_waitstatus ws;
2046 int stop_func_filled_in;
2047 CORE_ADDR stop_func_start;
2048 CORE_ADDR stop_func_end;
2049 const char *stop_func_name;
2052 /* True if the event thread hit the single-step breakpoint of
2053 another thread. Thus the event doesn't cause a stop, the thread
2054 needs to be single-stepped past the single-step breakpoint before
2055 we can switch back to the original stepping thread. */
2056 int hit_singlestep_breakpoint;
2059 /* Clear ECS and set it to point at TP. */
2062 reset_ecs (struct execution_control_state *ecs, struct thread_info *tp)
2064 memset (ecs, 0, sizeof (*ecs));
2065 ecs->event_thread = tp;
2066 ecs->ptid = tp->ptid;
2069 static void keep_going_pass_signal (struct execution_control_state *ecs);
2070 static void prepare_to_wait (struct execution_control_state *ecs);
2071 static int keep_going_stepped_thread (struct thread_info *tp);
2072 static step_over_what thread_still_needs_step_over (struct thread_info *tp);
2074 /* Are there any pending step-over requests? If so, run all we can
2075 now and return true. Otherwise, return false. */
2078 start_step_over (void)
2080 struct thread_info *tp, *next;
2082 /* Don't start a new step-over if we already have an in-line
2083 step-over operation ongoing. */
2084 if (step_over_info_valid_p ())
2087 for (tp = step_over_queue_head; tp != NULL; tp = next)
2089 struct execution_control_state ecss;
2090 struct execution_control_state *ecs = &ecss;
2091 step_over_what step_what;
2092 int must_be_in_line;
2094 gdb_assert (!tp->stop_requested);
2096 next = thread_step_over_chain_next (tp);
2098 /* If this inferior already has a displaced step in process,
2099 don't start a new one. */
2100 if (displaced_step_in_progress (ptid_get_pid (tp->ptid)))
2103 step_what = thread_still_needs_step_over (tp);
2104 must_be_in_line = ((step_what & STEP_OVER_WATCHPOINT)
2105 || ((step_what & STEP_OVER_BREAKPOINT)
2106 && !use_displaced_stepping (tp)));
2108 /* We currently stop all threads of all processes to step-over
2109 in-line. If we need to start a new in-line step-over, let
2110 any pending displaced steps finish first. */
2111 if (must_be_in_line && displaced_step_in_progress_any_inferior ())
2114 thread_step_over_chain_remove (tp);
2116 if (step_over_queue_head == NULL)
2119 fprintf_unfiltered (gdb_stdlog,
2120 "infrun: step-over queue now empty\n");
2123 if (tp->control.trap_expected
2127 internal_error (__FILE__, __LINE__,
2128 "[%s] has inconsistent state: "
2129 "trap_expected=%d, resumed=%d, executing=%d\n",
2130 target_pid_to_str (tp->ptid),
2131 tp->control.trap_expected,
2137 fprintf_unfiltered (gdb_stdlog,
2138 "infrun: resuming [%s] for step-over\n",
2139 target_pid_to_str (tp->ptid));
2141 /* keep_going_pass_signal skips the step-over if the breakpoint
2142 is no longer inserted. In all-stop, we want to keep looking
2143 for a thread that needs a step-over instead of resuming TP,
2144 because we wouldn't be able to resume anything else until the
2145 target stops again. In non-stop, the resume always resumes
2146 only TP, so it's OK to let the thread resume freely. */
2147 if (!target_is_non_stop_p () && !step_what)
2150 switch_to_thread (tp->ptid);
2151 reset_ecs (ecs, tp);
2152 keep_going_pass_signal (ecs);
2154 if (!ecs->wait_some_more)
2155 error (_("Command aborted."));
2157 gdb_assert (tp->resumed);
2159 /* If we started a new in-line step-over, we're done. */
2160 if (step_over_info_valid_p ())
2162 gdb_assert (tp->control.trap_expected);
2166 if (!target_is_non_stop_p ())
2168 /* On all-stop, shouldn't have resumed unless we needed a
2170 gdb_assert (tp->control.trap_expected
2171 || tp->step_after_step_resume_breakpoint);
2173 /* With remote targets (at least), in all-stop, we can't
2174 issue any further remote commands until the program stops
2179 /* Either the thread no longer needed a step-over, or a new
2180 displaced stepping sequence started. Even in the latter
2181 case, continue looking. Maybe we can also start another
2182 displaced step on a thread of other process. */
2188 /* Update global variables holding ptids to hold NEW_PTID if they were
2189 holding OLD_PTID. */
2191 infrun_thread_ptid_changed (ptid_t old_ptid, ptid_t new_ptid)
2193 struct displaced_step_inferior_state *displaced;
2195 if (ptid_equal (inferior_ptid, old_ptid))
2196 inferior_ptid = new_ptid;
2198 for (displaced = displaced_step_inferior_states;
2200 displaced = displaced->next)
2202 if (ptid_equal (displaced->step_ptid, old_ptid))
2203 displaced->step_ptid = new_ptid;
2210 /* Things to clean up if we QUIT out of resume (). */
2212 resume_cleanups (void *ignore)
2214 if (!ptid_equal (inferior_ptid, null_ptid))
2215 delete_single_step_breakpoints (inferior_thread ());
2220 static const char schedlock_off[] = "off";
2221 static const char schedlock_on[] = "on";
2222 static const char schedlock_step[] = "step";
2223 static const char schedlock_replay[] = "replay";
2224 static const char *const scheduler_enums[] = {
2231 static const char *scheduler_mode = schedlock_replay;
2233 show_scheduler_mode (struct ui_file *file, int from_tty,
2234 struct cmd_list_element *c, const char *value)
2236 fprintf_filtered (file,
2237 _("Mode for locking scheduler "
2238 "during execution is \"%s\".\n"),
2243 set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
2245 if (!target_can_lock_scheduler)
2247 scheduler_mode = schedlock_off;
2248 error (_("Target '%s' cannot support this command."), target_shortname);
2252 /* True if execution commands resume all threads of all processes by
2253 default; otherwise, resume only threads of the current inferior
2255 int sched_multi = 0;
2257 /* Try to setup for software single stepping over the specified location.
2258 Return 1 if target_resume() should use hardware single step.
2260 GDBARCH the current gdbarch.
2261 PC the location to step over. */
2264 maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc)
2268 if (execution_direction == EXEC_FORWARD
2269 && gdbarch_software_single_step_p (gdbarch))
2270 hw_step = !insert_single_step_breakpoints (gdbarch);
2278 user_visible_resume_ptid (int step)
2284 /* With non-stop mode on, threads are always handled
2286 resume_ptid = inferior_ptid;
2288 else if ((scheduler_mode == schedlock_on)
2289 || (scheduler_mode == schedlock_step && step))
2291 /* User-settable 'scheduler' mode requires solo thread
2293 resume_ptid = inferior_ptid;
2295 else if ((scheduler_mode == schedlock_replay)
2296 && target_record_will_replay (minus_one_ptid, execution_direction))
2298 /* User-settable 'scheduler' mode requires solo thread resume in replay
2300 resume_ptid = inferior_ptid;
2302 else if (!sched_multi && target_supports_multi_process ())
2304 /* Resume all threads of the current process (and none of other
2306 resume_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
2310 /* Resume all threads of all processes. */
2311 resume_ptid = RESUME_ALL;
2317 /* Return a ptid representing the set of threads that we will resume,
2318 in the perspective of the target, assuming run control handling
2319 does not require leaving some threads stopped (e.g., stepping past
2320 breakpoint). USER_STEP indicates whether we're about to start the
2321 target for a stepping command. */
2324 internal_resume_ptid (int user_step)
2326 /* In non-stop, we always control threads individually. Note that
2327 the target may always work in non-stop mode even with "set
2328 non-stop off", in which case user_visible_resume_ptid could
2329 return a wildcard ptid. */
2330 if (target_is_non_stop_p ())
2331 return inferior_ptid;
2333 return user_visible_resume_ptid (user_step);
2336 /* Wrapper for target_resume, that handles infrun-specific
2340 do_target_resume (ptid_t resume_ptid, int step, enum gdb_signal sig)
2342 struct thread_info *tp = inferior_thread ();
2344 gdb_assert (!tp->stop_requested);
2346 /* Install inferior's terminal modes. */
2347 target_terminal_inferior ();
2349 /* Avoid confusing the next resume, if the next stop/resume
2350 happens to apply to another thread. */
2351 tp->suspend.stop_signal = GDB_SIGNAL_0;
2353 /* Advise target which signals may be handled silently.
2355 If we have removed breakpoints because we are stepping over one
2356 in-line (in any thread), we need to receive all signals to avoid
2357 accidentally skipping a breakpoint during execution of a signal
2360 Likewise if we're displaced stepping, otherwise a trap for a
2361 breakpoint in a signal handler might be confused with the
2362 displaced step finishing. We don't make the displaced_step_fixup
2363 step distinguish the cases instead, because:
2365 - a backtrace while stopped in the signal handler would show the
2366 scratch pad as frame older than the signal handler, instead of
2367 the real mainline code.
2369 - when the thread is later resumed, the signal handler would
2370 return to the scratch pad area, which would no longer be
2372 if (step_over_info_valid_p ()
2373 || displaced_step_in_progress (ptid_get_pid (tp->ptid)))
2374 target_pass_signals (0, NULL);
2376 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
2378 target_resume (resume_ptid, step, sig);
2380 target_commit_resume ();
2383 /* Resume the inferior, but allow a QUIT. This is useful if the user
2384 wants to interrupt some lengthy single-stepping operation
2385 (for child processes, the SIGINT goes to the inferior, and so
2386 we get a SIGINT random_signal, but for remote debugging and perhaps
2387 other targets, that's not true).
2389 SIG is the signal to give the inferior (zero for none). */
2391 resume (enum gdb_signal sig)
2393 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
2394 struct regcache *regcache = get_current_regcache ();
2395 struct gdbarch *gdbarch = get_regcache_arch (regcache);
2396 struct thread_info *tp = inferior_thread ();
2397 CORE_ADDR pc = regcache_read_pc (regcache);
2398 struct address_space *aspace = get_regcache_aspace (regcache);
2400 /* This represents the user's step vs continue request. When
2401 deciding whether "set scheduler-locking step" applies, it's the
2402 user's intention that counts. */
2403 const int user_step = tp->control.stepping_command;
2404 /* This represents what we'll actually request the target to do.
2405 This can decay from a step to a continue, if e.g., we need to
2406 implement single-stepping with breakpoints (software
2410 gdb_assert (!tp->stop_requested);
2411 gdb_assert (!thread_is_in_step_over_chain (tp));
2415 if (tp->suspend.waitstatus_pending_p)
2421 statstr = target_waitstatus_to_string (&tp->suspend.waitstatus);
2422 fprintf_unfiltered (gdb_stdlog,
2423 "infrun: resume: thread %s has pending wait status %s "
2424 "(currently_stepping=%d).\n",
2425 target_pid_to_str (tp->ptid), statstr,
2426 currently_stepping (tp));
2432 /* FIXME: What should we do if we are supposed to resume this
2433 thread with a signal? Maybe we should maintain a queue of
2434 pending signals to deliver. */
2435 if (sig != GDB_SIGNAL_0)
2437 warning (_("Couldn't deliver signal %s to %s."),
2438 gdb_signal_to_name (sig), target_pid_to_str (tp->ptid));
2441 tp->suspend.stop_signal = GDB_SIGNAL_0;
2442 discard_cleanups (old_cleanups);
2444 if (target_can_async_p ())
2449 tp->stepped_breakpoint = 0;
2451 /* Depends on stepped_breakpoint. */
2452 step = currently_stepping (tp);
2454 if (current_inferior ()->waiting_for_vfork_done)
2456 /* Don't try to single-step a vfork parent that is waiting for
2457 the child to get out of the shared memory region (by exec'ing
2458 or exiting). This is particularly important on software
2459 single-step archs, as the child process would trip on the
2460 software single step breakpoint inserted for the parent
2461 process. Since the parent will not actually execute any
2462 instruction until the child is out of the shared region (such
2463 are vfork's semantics), it is safe to simply continue it.
2464 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2465 the parent, and tell it to `keep_going', which automatically
2466 re-sets it stepping. */
2468 fprintf_unfiltered (gdb_stdlog,
2469 "infrun: resume : clear step\n");
2474 fprintf_unfiltered (gdb_stdlog,
2475 "infrun: resume (step=%d, signal=%s), "
2476 "trap_expected=%d, current thread [%s] at %s\n",
2477 step, gdb_signal_to_symbol_string (sig),
2478 tp->control.trap_expected,
2479 target_pid_to_str (inferior_ptid),
2480 paddress (gdbarch, pc));
2482 /* Normally, by the time we reach `resume', the breakpoints are either
2483 removed or inserted, as appropriate. The exception is if we're sitting
2484 at a permanent breakpoint; we need to step over it, but permanent
2485 breakpoints can't be removed. So we have to test for it here. */
2486 if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here)
2488 if (sig != GDB_SIGNAL_0)
2490 /* We have a signal to pass to the inferior. The resume
2491 may, or may not take us to the signal handler. If this
2492 is a step, we'll need to stop in the signal handler, if
2493 there's one, (if the target supports stepping into
2494 handlers), or in the next mainline instruction, if
2495 there's no handler. If this is a continue, we need to be
2496 sure to run the handler with all breakpoints inserted.
2497 In all cases, set a breakpoint at the current address
2498 (where the handler returns to), and once that breakpoint
2499 is hit, resume skipping the permanent breakpoint. If
2500 that breakpoint isn't hit, then we've stepped into the
2501 signal handler (or hit some other event). We'll delete
2502 the step-resume breakpoint then. */
2505 fprintf_unfiltered (gdb_stdlog,
2506 "infrun: resume: skipping permanent breakpoint, "
2507 "deliver signal first\n");
2509 clear_step_over_info ();
2510 tp->control.trap_expected = 0;
2512 if (tp->control.step_resume_breakpoint == NULL)
2514 /* Set a "high-priority" step-resume, as we don't want
2515 user breakpoints at PC to trigger (again) when this
2517 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2518 gdb_assert (tp->control.step_resume_breakpoint->loc->permanent);
2520 tp->step_after_step_resume_breakpoint = step;
2523 insert_breakpoints ();
2527 /* There's no signal to pass, we can go ahead and skip the
2528 permanent breakpoint manually. */
2530 fprintf_unfiltered (gdb_stdlog,
2531 "infrun: resume: skipping permanent breakpoint\n");
2532 gdbarch_skip_permanent_breakpoint (gdbarch, regcache);
2533 /* Update pc to reflect the new address from which we will
2534 execute instructions. */
2535 pc = regcache_read_pc (regcache);
2539 /* We've already advanced the PC, so the stepping part
2540 is done. Now we need to arrange for a trap to be
2541 reported to handle_inferior_event. Set a breakpoint
2542 at the current PC, and run to it. Don't update
2543 prev_pc, because if we end in
2544 switch_back_to_stepped_thread, we want the "expected
2545 thread advanced also" branch to be taken. IOW, we
2546 don't want this thread to step further from PC
2548 gdb_assert (!step_over_info_valid_p ());
2549 insert_single_step_breakpoint (gdbarch, aspace, pc);
2550 insert_breakpoints ();
2552 resume_ptid = internal_resume_ptid (user_step);
2553 do_target_resume (resume_ptid, 0, GDB_SIGNAL_0);
2554 discard_cleanups (old_cleanups);
2561 /* If we have a breakpoint to step over, make sure to do a single
2562 step only. Same if we have software watchpoints. */
2563 if (tp->control.trap_expected || bpstat_should_step ())
2564 tp->control.may_range_step = 0;
2566 /* If enabled, step over breakpoints by executing a copy of the
2567 instruction at a different address.
2569 We can't use displaced stepping when we have a signal to deliver;
2570 the comments for displaced_step_prepare explain why. The
2571 comments in the handle_inferior event for dealing with 'random
2572 signals' explain what we do instead.
2574 We can't use displaced stepping when we are waiting for vfork_done
2575 event, displaced stepping breaks the vfork child similarly as single
2576 step software breakpoint. */
2577 if (tp->control.trap_expected
2578 && use_displaced_stepping (tp)
2579 && !step_over_info_valid_p ()
2580 && sig == GDB_SIGNAL_0
2581 && !current_inferior ()->waiting_for_vfork_done)
2583 int prepared = displaced_step_prepare (inferior_ptid);
2588 fprintf_unfiltered (gdb_stdlog,
2589 "Got placed in step-over queue\n");
2591 tp->control.trap_expected = 0;
2592 discard_cleanups (old_cleanups);
2595 else if (prepared < 0)
2597 /* Fallback to stepping over the breakpoint in-line. */
2599 if (target_is_non_stop_p ())
2600 stop_all_threads ();
2602 set_step_over_info (get_regcache_aspace (regcache),
2603 regcache_read_pc (regcache), 0, tp->global_num);
2605 step = maybe_software_singlestep (gdbarch, pc);
2607 insert_breakpoints ();
2609 else if (prepared > 0)
2611 struct displaced_step_inferior_state *displaced;
2613 /* Update pc to reflect the new address from which we will
2614 execute instructions due to displaced stepping. */
2615 pc = regcache_read_pc (get_thread_regcache (inferior_ptid));
2617 displaced = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
2618 step = gdbarch_displaced_step_hw_singlestep (gdbarch,
2619 displaced->step_closure);
2623 /* Do we need to do it the hard way, w/temp breakpoints? */
2625 step = maybe_software_singlestep (gdbarch, pc);
2627 /* Currently, our software single-step implementation leads to different
2628 results than hardware single-stepping in one situation: when stepping
2629 into delivering a signal which has an associated signal handler,
2630 hardware single-step will stop at the first instruction of the handler,
2631 while software single-step will simply skip execution of the handler.
2633 For now, this difference in behavior is accepted since there is no
2634 easy way to actually implement single-stepping into a signal handler
2635 without kernel support.
2637 However, there is one scenario where this difference leads to follow-on
2638 problems: if we're stepping off a breakpoint by removing all breakpoints
2639 and then single-stepping. In this case, the software single-step
2640 behavior means that even if there is a *breakpoint* in the signal
2641 handler, GDB still would not stop.
2643 Fortunately, we can at least fix this particular issue. We detect
2644 here the case where we are about to deliver a signal while software
2645 single-stepping with breakpoints removed. In this situation, we
2646 revert the decisions to remove all breakpoints and insert single-
2647 step breakpoints, and instead we install a step-resume breakpoint
2648 at the current address, deliver the signal without stepping, and
2649 once we arrive back at the step-resume breakpoint, actually step
2650 over the breakpoint we originally wanted to step over. */
2651 if (thread_has_single_step_breakpoints_set (tp)
2652 && sig != GDB_SIGNAL_0
2653 && step_over_info_valid_p ())
2655 /* If we have nested signals or a pending signal is delivered
2656 immediately after a handler returns, might might already have
2657 a step-resume breakpoint set on the earlier handler. We cannot
2658 set another step-resume breakpoint; just continue on until the
2659 original breakpoint is hit. */
2660 if (tp->control.step_resume_breakpoint == NULL)
2662 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2663 tp->step_after_step_resume_breakpoint = 1;
2666 delete_single_step_breakpoints (tp);
2668 clear_step_over_info ();
2669 tp->control.trap_expected = 0;
2671 insert_breakpoints ();
2674 /* If STEP is set, it's a request to use hardware stepping
2675 facilities. But in that case, we should never
2676 use singlestep breakpoint. */
2677 gdb_assert (!(thread_has_single_step_breakpoints_set (tp) && step));
2679 /* Decide the set of threads to ask the target to resume. */
2680 if (tp->control.trap_expected)
2682 /* We're allowing a thread to run past a breakpoint it has
2683 hit, either by single-stepping the thread with the breakpoint
2684 removed, or by displaced stepping, with the breakpoint inserted.
2685 In the former case, we need to single-step only this thread,
2686 and keep others stopped, as they can miss this breakpoint if
2687 allowed to run. That's not really a problem for displaced
2688 stepping, but, we still keep other threads stopped, in case
2689 another thread is also stopped for a breakpoint waiting for
2690 its turn in the displaced stepping queue. */
2691 resume_ptid = inferior_ptid;
2694 resume_ptid = internal_resume_ptid (user_step);
2696 if (execution_direction != EXEC_REVERSE
2697 && step && breakpoint_inserted_here_p (aspace, pc))
2699 /* There are two cases where we currently need to step a
2700 breakpoint instruction when we have a signal to deliver:
2702 - See handle_signal_stop where we handle random signals that
2703 could take out us out of the stepping range. Normally, in
2704 that case we end up continuing (instead of stepping) over the
2705 signal handler with a breakpoint at PC, but there are cases
2706 where we should _always_ single-step, even if we have a
2707 step-resume breakpoint, like when a software watchpoint is
2708 set. Assuming single-stepping and delivering a signal at the
2709 same time would takes us to the signal handler, then we could
2710 have removed the breakpoint at PC to step over it. However,
2711 some hardware step targets (like e.g., Mac OS) can't step
2712 into signal handlers, and for those, we need to leave the
2713 breakpoint at PC inserted, as otherwise if the handler
2714 recurses and executes PC again, it'll miss the breakpoint.
2715 So we leave the breakpoint inserted anyway, but we need to
2716 record that we tried to step a breakpoint instruction, so
2717 that adjust_pc_after_break doesn't end up confused.
2719 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2720 in one thread after another thread that was stepping had been
2721 momentarily paused for a step-over. When we re-resume the
2722 stepping thread, it may be resumed from that address with a
2723 breakpoint that hasn't trapped yet. Seen with
2724 gdb.threads/non-stop-fair-events.exp, on targets that don't
2725 do displaced stepping. */
2728 fprintf_unfiltered (gdb_stdlog,
2729 "infrun: resume: [%s] stepped breakpoint\n",
2730 target_pid_to_str (tp->ptid));
2732 tp->stepped_breakpoint = 1;
2734 /* Most targets can step a breakpoint instruction, thus
2735 executing it normally. But if this one cannot, just
2736 continue and we will hit it anyway. */
2737 if (gdbarch_cannot_step_breakpoint (gdbarch))
2742 && tp->control.trap_expected
2743 && use_displaced_stepping (tp)
2744 && !step_over_info_valid_p ())
2746 struct regcache *resume_regcache = get_thread_regcache (tp->ptid);
2747 struct gdbarch *resume_gdbarch = get_regcache_arch (resume_regcache);
2748 CORE_ADDR actual_pc = regcache_read_pc (resume_regcache);
2751 fprintf_unfiltered (gdb_stdlog, "displaced: run %s: ",
2752 paddress (resume_gdbarch, actual_pc));
2753 read_memory (actual_pc, buf, sizeof (buf));
2754 displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
2757 if (tp->control.may_range_step)
2759 /* If we're resuming a thread with the PC out of the step
2760 range, then we're doing some nested/finer run control
2761 operation, like stepping the thread out of the dynamic
2762 linker or the displaced stepping scratch pad. We
2763 shouldn't have allowed a range step then. */
2764 gdb_assert (pc_in_thread_step_range (pc, tp));
2767 do_target_resume (resume_ptid, step, sig);
2769 discard_cleanups (old_cleanups);
2776 /* Counter that tracks number of user visible stops. This can be used
2777 to tell whether a command has proceeded the inferior past the
2778 current location. This allows e.g., inferior function calls in
2779 breakpoint commands to not interrupt the command list. When the
2780 call finishes successfully, the inferior is standing at the same
2781 breakpoint as if nothing happened (and so we don't call
2783 static ULONGEST current_stop_id;
2790 return current_stop_id;
2793 /* Called when we report a user visible stop. */
2801 /* Clear out all variables saying what to do when inferior is continued.
2802 First do this, then set the ones you want, then call `proceed'. */
2805 clear_proceed_status_thread (struct thread_info *tp)
2808 fprintf_unfiltered (gdb_stdlog,
2809 "infrun: clear_proceed_status_thread (%s)\n",
2810 target_pid_to_str (tp->ptid));
2812 /* If we're starting a new sequence, then the previous finished
2813 single-step is no longer relevant. */
2814 if (tp->suspend.waitstatus_pending_p)
2816 if (tp->suspend.stop_reason == TARGET_STOPPED_BY_SINGLE_STEP)
2819 fprintf_unfiltered (gdb_stdlog,
2820 "infrun: clear_proceed_status: pending "
2821 "event of %s was a finished step. "
2823 target_pid_to_str (tp->ptid));
2825 tp->suspend.waitstatus_pending_p = 0;
2826 tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON;
2828 else if (debug_infrun)
2832 statstr = target_waitstatus_to_string (&tp->suspend.waitstatus);
2833 fprintf_unfiltered (gdb_stdlog,
2834 "infrun: clear_proceed_status_thread: thread %s "
2835 "has pending wait status %s "
2836 "(currently_stepping=%d).\n",
2837 target_pid_to_str (tp->ptid), statstr,
2838 currently_stepping (tp));
2843 /* If this signal should not be seen by program, give it zero.
2844 Used for debugging signals. */
2845 if (!signal_pass_state (tp->suspend.stop_signal))
2846 tp->suspend.stop_signal = GDB_SIGNAL_0;
2848 thread_fsm_delete (tp->thread_fsm);
2849 tp->thread_fsm = NULL;
2851 tp->control.trap_expected = 0;
2852 tp->control.step_range_start = 0;
2853 tp->control.step_range_end = 0;
2854 tp->control.may_range_step = 0;
2855 tp->control.step_frame_id = null_frame_id;
2856 tp->control.step_stack_frame_id = null_frame_id;
2857 tp->control.step_over_calls = STEP_OVER_UNDEBUGGABLE;
2858 tp->control.step_start_function = NULL;
2859 tp->stop_requested = 0;
2861 tp->control.stop_step = 0;
2863 tp->control.proceed_to_finish = 0;
2865 tp->control.stepping_command = 0;
2867 /* Discard any remaining commands or status from previous stop. */
2868 bpstat_clear (&tp->control.stop_bpstat);
2872 clear_proceed_status (int step)
2874 /* With scheduler-locking replay, stop replaying other threads if we're
2875 not replaying the user-visible resume ptid.
2877 This is a convenience feature to not require the user to explicitly
2878 stop replaying the other threads. We're assuming that the user's
2879 intent is to resume tracing the recorded process. */
2880 if (!non_stop && scheduler_mode == schedlock_replay
2881 && target_record_is_replaying (minus_one_ptid)
2882 && !target_record_will_replay (user_visible_resume_ptid (step),
2883 execution_direction))
2884 target_record_stop_replaying ();
2888 struct thread_info *tp;
2891 resume_ptid = user_visible_resume_ptid (step);
2893 /* In all-stop mode, delete the per-thread status of all threads
2894 we're about to resume, implicitly and explicitly. */
2895 ALL_NON_EXITED_THREADS (tp)
2897 if (!ptid_match (tp->ptid, resume_ptid))
2899 clear_proceed_status_thread (tp);
2903 if (!ptid_equal (inferior_ptid, null_ptid))
2905 struct inferior *inferior;
2909 /* If in non-stop mode, only delete the per-thread status of
2910 the current thread. */
2911 clear_proceed_status_thread (inferior_thread ());
2914 inferior = current_inferior ();
2915 inferior->control.stop_soon = NO_STOP_QUIETLY;
2918 observer_notify_about_to_proceed ();
2921 /* Returns true if TP is still stopped at a breakpoint that needs
2922 stepping-over in order to make progress. If the breakpoint is gone
2923 meanwhile, we can skip the whole step-over dance. */
2926 thread_still_needs_step_over_bp (struct thread_info *tp)
2928 if (tp->stepping_over_breakpoint)
2930 struct regcache *regcache = get_thread_regcache (tp->ptid);
2932 if (breakpoint_here_p (get_regcache_aspace (regcache),
2933 regcache_read_pc (regcache))
2934 == ordinary_breakpoint_here)
2937 tp->stepping_over_breakpoint = 0;
2943 /* Check whether thread TP still needs to start a step-over in order
2944 to make progress when resumed. Returns an bitwise or of enum
2945 step_over_what bits, indicating what needs to be stepped over. */
2947 static step_over_what
2948 thread_still_needs_step_over (struct thread_info *tp)
2950 step_over_what what = 0;
2952 if (thread_still_needs_step_over_bp (tp))
2953 what |= STEP_OVER_BREAKPOINT;
2955 if (tp->stepping_over_watchpoint
2956 && !target_have_steppable_watchpoint)
2957 what |= STEP_OVER_WATCHPOINT;
2962 /* Returns true if scheduler locking applies. STEP indicates whether
2963 we're about to do a step/next-like command to a thread. */
2966 schedlock_applies (struct thread_info *tp)
2968 return (scheduler_mode == schedlock_on
2969 || (scheduler_mode == schedlock_step
2970 && tp->control.stepping_command)
2971 || (scheduler_mode == schedlock_replay
2972 && target_record_will_replay (minus_one_ptid,
2973 execution_direction)));
2976 /* Basic routine for continuing the program in various fashions.
2978 ADDR is the address to resume at, or -1 for resume where stopped.
2979 SIGGNAL is the signal to give it, or 0 for none,
2980 or -1 for act according to how it stopped.
2981 STEP is nonzero if should trap after one instruction.
2982 -1 means return after that and print nothing.
2983 You should probably set various step_... variables
2984 before calling here, if you are stepping.
2986 You should call clear_proceed_status before calling proceed. */
2989 proceed (CORE_ADDR addr, enum gdb_signal siggnal)
2991 struct regcache *regcache;
2992 struct gdbarch *gdbarch;
2993 struct thread_info *tp;
2995 struct address_space *aspace;
2997 struct execution_control_state ecss;
2998 struct execution_control_state *ecs = &ecss;
2999 struct cleanup *old_chain;
3000 struct cleanup *defer_resume_cleanup;
3003 /* If we're stopped at a fork/vfork, follow the branch set by the
3004 "set follow-fork-mode" command; otherwise, we'll just proceed
3005 resuming the current thread. */
3006 if (!follow_fork ())
3008 /* The target for some reason decided not to resume. */
3010 if (target_can_async_p ())
3011 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
3015 /* We'll update this if & when we switch to a new thread. */
3016 previous_inferior_ptid = inferior_ptid;
3018 regcache = get_current_regcache ();
3019 gdbarch = get_regcache_arch (regcache);
3020 aspace = get_regcache_aspace (regcache);
3021 pc = regcache_read_pc (regcache);
3022 tp = inferior_thread ();
3024 /* Fill in with reasonable starting values. */
3025 init_thread_stepping_state (tp);
3027 gdb_assert (!thread_is_in_step_over_chain (tp));
3029 if (addr == (CORE_ADDR) -1)
3032 && breakpoint_here_p (aspace, pc) == ordinary_breakpoint_here
3033 && execution_direction != EXEC_REVERSE)
3034 /* There is a breakpoint at the address we will resume at,
3035 step one instruction before inserting breakpoints so that
3036 we do not stop right away (and report a second hit at this
3039 Note, we don't do this in reverse, because we won't
3040 actually be executing the breakpoint insn anyway.
3041 We'll be (un-)executing the previous instruction. */
3042 tp->stepping_over_breakpoint = 1;
3043 else if (gdbarch_single_step_through_delay_p (gdbarch)
3044 && gdbarch_single_step_through_delay (gdbarch,
3045 get_current_frame ()))
3046 /* We stepped onto an instruction that needs to be stepped
3047 again before re-inserting the breakpoint, do so. */
3048 tp->stepping_over_breakpoint = 1;
3052 regcache_write_pc (regcache, addr);
3055 if (siggnal != GDB_SIGNAL_DEFAULT)
3056 tp->suspend.stop_signal = siggnal;
3058 resume_ptid = user_visible_resume_ptid (tp->control.stepping_command);
3060 /* If an exception is thrown from this point on, make sure to
3061 propagate GDB's knowledge of the executing state to the
3062 frontend/user running state. */
3063 old_chain = make_cleanup (finish_thread_state_cleanup, &resume_ptid);
3065 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3066 threads (e.g., we might need to set threads stepping over
3067 breakpoints first), from the user/frontend's point of view, all
3068 threads in RESUME_PTID are now running. Unless we're calling an
3069 inferior function, as in that case we pretend the inferior
3070 doesn't run at all. */
3071 if (!tp->control.in_infcall)
3072 set_running (resume_ptid, 1);
3075 fprintf_unfiltered (gdb_stdlog,
3076 "infrun: proceed (addr=%s, signal=%s)\n",
3077 paddress (gdbarch, addr),
3078 gdb_signal_to_symbol_string (siggnal));
3080 annotate_starting ();
3082 /* Make sure that output from GDB appears before output from the
3084 gdb_flush (gdb_stdout);
3086 /* In a multi-threaded task we may select another thread and
3087 then continue or step.
3089 But if a thread that we're resuming had stopped at a breakpoint,
3090 it will immediately cause another breakpoint stop without any
3091 execution (i.e. it will report a breakpoint hit incorrectly). So
3092 we must step over it first.
3094 Look for threads other than the current (TP) that reported a
3095 breakpoint hit and haven't been resumed yet since. */
3097 /* If scheduler locking applies, we can avoid iterating over all
3099 if (!non_stop && !schedlock_applies (tp))
3101 struct thread_info *current = tp;
3103 ALL_NON_EXITED_THREADS (tp)
3105 /* Ignore the current thread here. It's handled
3110 /* Ignore threads of processes we're not resuming. */
3111 if (!ptid_match (tp->ptid, resume_ptid))
3114 if (!thread_still_needs_step_over (tp))
3117 gdb_assert (!thread_is_in_step_over_chain (tp));
3120 fprintf_unfiltered (gdb_stdlog,
3121 "infrun: need to step-over [%s] first\n",
3122 target_pid_to_str (tp->ptid));
3124 thread_step_over_chain_enqueue (tp);
3130 /* Enqueue the current thread last, so that we move all other
3131 threads over their breakpoints first. */
3132 if (tp->stepping_over_breakpoint)
3133 thread_step_over_chain_enqueue (tp);
3135 /* If the thread isn't started, we'll still need to set its prev_pc,
3136 so that switch_back_to_stepped_thread knows the thread hasn't
3137 advanced. Must do this before resuming any thread, as in
3138 all-stop/remote, once we resume we can't send any other packet
3139 until the target stops again. */
3140 tp->prev_pc = regcache_read_pc (regcache);
3142 defer_resume_cleanup = make_cleanup_defer_target_commit_resume ();
3144 started = start_step_over ();
3146 if (step_over_info_valid_p ())
3148 /* Either this thread started a new in-line step over, or some
3149 other thread was already doing one. In either case, don't
3150 resume anything else until the step-over is finished. */
3152 else if (started && !target_is_non_stop_p ())
3154 /* A new displaced stepping sequence was started. In all-stop,
3155 we can't talk to the target anymore until it next stops. */
3157 else if (!non_stop && target_is_non_stop_p ())
3159 /* In all-stop, but the target is always in non-stop mode.
3160 Start all other threads that are implicitly resumed too. */
3161 ALL_NON_EXITED_THREADS (tp)
3163 /* Ignore threads of processes we're not resuming. */
3164 if (!ptid_match (tp->ptid, resume_ptid))
3170 fprintf_unfiltered (gdb_stdlog,
3171 "infrun: proceed: [%s] resumed\n",
3172 target_pid_to_str (tp->ptid));
3173 gdb_assert (tp->executing || tp->suspend.waitstatus_pending_p);
3177 if (thread_is_in_step_over_chain (tp))
3180 fprintf_unfiltered (gdb_stdlog,
3181 "infrun: proceed: [%s] needs step-over\n",
3182 target_pid_to_str (tp->ptid));
3187 fprintf_unfiltered (gdb_stdlog,
3188 "infrun: proceed: resuming %s\n",
3189 target_pid_to_str (tp->ptid));
3191 reset_ecs (ecs, tp);
3192 switch_to_thread (tp->ptid);
3193 keep_going_pass_signal (ecs);
3194 if (!ecs->wait_some_more)
3195 error (_("Command aborted."));
3198 else if (!tp->resumed && !thread_is_in_step_over_chain (tp))
3200 /* The thread wasn't started, and isn't queued, run it now. */
3201 reset_ecs (ecs, tp);
3202 switch_to_thread (tp->ptid);
3203 keep_going_pass_signal (ecs);
3204 if (!ecs->wait_some_more)
3205 error (_("Command aborted."));
3208 do_cleanups (defer_resume_cleanup);
3209 target_commit_resume ();
3211 discard_cleanups (old_chain);
3213 /* Tell the event loop to wait for it to stop. If the target
3214 supports asynchronous execution, it'll do this from within
3216 if (!target_can_async_p ())
3217 mark_async_event_handler (infrun_async_inferior_event_token);
3221 /* Start remote-debugging of a machine over a serial link. */
3224 start_remote (int from_tty)
3226 struct inferior *inferior;
3228 inferior = current_inferior ();
3229 inferior->control.stop_soon = STOP_QUIETLY_REMOTE;
3231 /* Always go on waiting for the target, regardless of the mode. */
3232 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3233 indicate to wait_for_inferior that a target should timeout if
3234 nothing is returned (instead of just blocking). Because of this,
3235 targets expecting an immediate response need to, internally, set
3236 things up so that the target_wait() is forced to eventually
3238 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3239 differentiate to its caller what the state of the target is after
3240 the initial open has been performed. Here we're assuming that
3241 the target has stopped. It should be possible to eventually have
3242 target_open() return to the caller an indication that the target
3243 is currently running and GDB state should be set to the same as
3244 for an async run. */
3245 wait_for_inferior ();
3247 /* Now that the inferior has stopped, do any bookkeeping like
3248 loading shared libraries. We want to do this before normal_stop,
3249 so that the displayed frame is up to date. */
3250 post_create_inferior (¤t_target, from_tty);
3255 /* Initialize static vars when a new inferior begins. */
3258 init_wait_for_inferior (void)
3260 /* These are meaningless until the first time through wait_for_inferior. */
3262 breakpoint_init_inferior (inf_starting);
3264 clear_proceed_status (0);
3266 target_last_wait_ptid = minus_one_ptid;
3268 previous_inferior_ptid = inferior_ptid;
3270 /* Discard any skipped inlined frames. */
3271 clear_inline_frame_state (minus_one_ptid);
3276 static void handle_inferior_event (struct execution_control_state *ecs);
3278 static void handle_step_into_function (struct gdbarch *gdbarch,
3279 struct execution_control_state *ecs);
3280 static void handle_step_into_function_backward (struct gdbarch *gdbarch,
3281 struct execution_control_state *ecs);
3282 static void handle_signal_stop (struct execution_control_state *ecs);
3283 static void check_exception_resume (struct execution_control_state *,
3284 struct frame_info *);
3286 static void end_stepping_range (struct execution_control_state *ecs);
3287 static void stop_waiting (struct execution_control_state *ecs);
3288 static void keep_going (struct execution_control_state *ecs);
3289 static void process_event_stop_test (struct execution_control_state *ecs);
3290 static int switch_back_to_stepped_thread (struct execution_control_state *ecs);
3292 /* This function is attached as a "thread_stop_requested" observer.
3293 Cleanup local state that assumed the PTID was to be resumed, and
3294 report the stop to the frontend. */
3297 infrun_thread_stop_requested (ptid_t ptid)
3299 struct thread_info *tp;
3301 /* PTID was requested to stop. If the thread was already stopped,
3302 but the user/frontend doesn't know about that yet (e.g., the
3303 thread had been temporarily paused for some step-over), set up
3304 for reporting the stop now. */
3305 ALL_NON_EXITED_THREADS (tp)
3306 if (ptid_match (tp->ptid, ptid))
3308 if (tp->state != THREAD_RUNNING)
3313 /* Remove matching threads from the step-over queue, so
3314 start_step_over doesn't try to resume them
3316 if (thread_is_in_step_over_chain (tp))
3317 thread_step_over_chain_remove (tp);
3319 /* If the thread is stopped, but the user/frontend doesn't
3320 know about that yet, queue a pending event, as if the
3321 thread had just stopped now. Unless the thread already had
3323 if (!tp->suspend.waitstatus_pending_p)
3325 tp->suspend.waitstatus_pending_p = 1;
3326 tp->suspend.waitstatus.kind = TARGET_WAITKIND_STOPPED;
3327 tp->suspend.waitstatus.value.sig = GDB_SIGNAL_0;
3330 /* Clear the inline-frame state, since we're re-processing the
3332 clear_inline_frame_state (tp->ptid);
3334 /* If this thread was paused because some other thread was
3335 doing an inline-step over, let that finish first. Once
3336 that happens, we'll restart all threads and consume pending
3337 stop events then. */
3338 if (step_over_info_valid_p ())
3341 /* Otherwise we can process the (new) pending event now. Set
3342 it so this pending event is considered by
3349 infrun_thread_thread_exit (struct thread_info *tp, int silent)
3351 if (ptid_equal (target_last_wait_ptid, tp->ptid))
3352 nullify_last_target_wait_ptid ();
3355 /* Delete the step resume, single-step and longjmp/exception resume
3356 breakpoints of TP. */
3359 delete_thread_infrun_breakpoints (struct thread_info *tp)
3361 delete_step_resume_breakpoint (tp);
3362 delete_exception_resume_breakpoint (tp);
3363 delete_single_step_breakpoints (tp);
3366 /* If the target still has execution, call FUNC for each thread that
3367 just stopped. In all-stop, that's all the non-exited threads; in
3368 non-stop, that's the current thread, only. */
3370 typedef void (*for_each_just_stopped_thread_callback_func)
3371 (struct thread_info *tp);
3374 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func)
3376 if (!target_has_execution || ptid_equal (inferior_ptid, null_ptid))
3379 if (target_is_non_stop_p ())
3381 /* If in non-stop mode, only the current thread stopped. */
3382 func (inferior_thread ());
3386 struct thread_info *tp;
3388 /* In all-stop mode, all threads have stopped. */
3389 ALL_NON_EXITED_THREADS (tp)
3396 /* Delete the step resume and longjmp/exception resume breakpoints of
3397 the threads that just stopped. */
3400 delete_just_stopped_threads_infrun_breakpoints (void)
3402 for_each_just_stopped_thread (delete_thread_infrun_breakpoints);
3405 /* Delete the single-step breakpoints of the threads that just
3409 delete_just_stopped_threads_single_step_breakpoints (void)
3411 for_each_just_stopped_thread (delete_single_step_breakpoints);
3414 /* A cleanup wrapper. */
3417 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg)
3419 delete_just_stopped_threads_infrun_breakpoints ();
3425 print_target_wait_results (ptid_t waiton_ptid, ptid_t result_ptid,
3426 const struct target_waitstatus *ws)
3428 char *status_string = target_waitstatus_to_string (ws);
3431 /* The text is split over several lines because it was getting too long.
3432 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3433 output as a unit; we want only one timestamp printed if debug_timestamp
3436 stb.printf ("infrun: target_wait (%d.%ld.%ld",
3437 ptid_get_pid (waiton_ptid),
3438 ptid_get_lwp (waiton_ptid),
3439 ptid_get_tid (waiton_ptid));
3440 if (ptid_get_pid (waiton_ptid) != -1)
3441 stb.printf (" [%s]", target_pid_to_str (waiton_ptid));
3442 stb.printf (", status) =\n");
3443 stb.printf ("infrun: %d.%ld.%ld [%s],\n",
3444 ptid_get_pid (result_ptid),
3445 ptid_get_lwp (result_ptid),
3446 ptid_get_tid (result_ptid),
3447 target_pid_to_str (result_ptid));
3448 stb.printf ("infrun: %s\n", status_string);
3450 /* This uses %s in part to handle %'s in the text, but also to avoid
3451 a gcc error: the format attribute requires a string literal. */
3452 fprintf_unfiltered (gdb_stdlog, "%s", stb.c_str ());
3454 xfree (status_string);
3457 /* Select a thread at random, out of those which are resumed and have
3460 static struct thread_info *
3461 random_pending_event_thread (ptid_t waiton_ptid)
3463 struct thread_info *event_tp;
3465 int random_selector;
3467 /* First see how many events we have. Count only resumed threads
3468 that have an event pending. */
3469 ALL_NON_EXITED_THREADS (event_tp)
3470 if (ptid_match (event_tp->ptid, waiton_ptid)
3471 && event_tp->resumed
3472 && event_tp->suspend.waitstatus_pending_p)
3475 if (num_events == 0)
3478 /* Now randomly pick a thread out of those that have had events. */
3479 random_selector = (int)
3480 ((num_events * (double) rand ()) / (RAND_MAX + 1.0));
3482 if (debug_infrun && num_events > 1)
3483 fprintf_unfiltered (gdb_stdlog,
3484 "infrun: Found %d events, selecting #%d\n",
3485 num_events, random_selector);
3487 /* Select the Nth thread that has had an event. */
3488 ALL_NON_EXITED_THREADS (event_tp)
3489 if (ptid_match (event_tp->ptid, waiton_ptid)
3490 && event_tp->resumed
3491 && event_tp->suspend.waitstatus_pending_p)
3492 if (random_selector-- == 0)
3498 /* Wrapper for target_wait that first checks whether threads have
3499 pending statuses to report before actually asking the target for
3503 do_target_wait (ptid_t ptid, struct target_waitstatus *status, int options)
3506 struct thread_info *tp;
3508 /* First check if there is a resumed thread with a wait status
3510 if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid))
3512 tp = random_pending_event_thread (ptid);
3517 fprintf_unfiltered (gdb_stdlog,
3518 "infrun: Waiting for specific thread %s.\n",
3519 target_pid_to_str (ptid));
3521 /* We have a specific thread to check. */
3522 tp = find_thread_ptid (ptid);
3523 gdb_assert (tp != NULL);
3524 if (!tp->suspend.waitstatus_pending_p)
3529 && (tp->suspend.stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3530 || tp->suspend.stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT))
3532 struct regcache *regcache = get_thread_regcache (tp->ptid);
3533 struct gdbarch *gdbarch = get_regcache_arch (regcache);
3537 pc = regcache_read_pc (regcache);
3539 if (pc != tp->suspend.stop_pc)
3542 fprintf_unfiltered (gdb_stdlog,
3543 "infrun: PC of %s changed. was=%s, now=%s\n",
3544 target_pid_to_str (tp->ptid),
3545 paddress (gdbarch, tp->prev_pc),
3546 paddress (gdbarch, pc));
3549 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc))
3552 fprintf_unfiltered (gdb_stdlog,
3553 "infrun: previous breakpoint of %s, at %s gone\n",
3554 target_pid_to_str (tp->ptid),
3555 paddress (gdbarch, pc));
3563 fprintf_unfiltered (gdb_stdlog,
3564 "infrun: pending event of %s cancelled.\n",
3565 target_pid_to_str (tp->ptid));
3567 tp->suspend.waitstatus.kind = TARGET_WAITKIND_SPURIOUS;
3568 tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON;
3578 statstr = target_waitstatus_to_string (&tp->suspend.waitstatus);
3579 fprintf_unfiltered (gdb_stdlog,
3580 "infrun: Using pending wait status %s for %s.\n",
3582 target_pid_to_str (tp->ptid));
3586 /* Now that we've selected our final event LWP, un-adjust its PC
3587 if it was a software breakpoint (and the target doesn't
3588 always adjust the PC itself). */
3589 if (tp->suspend.stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3590 && !target_supports_stopped_by_sw_breakpoint ())
3592 struct regcache *regcache;
3593 struct gdbarch *gdbarch;
3596 regcache = get_thread_regcache (tp->ptid);
3597 gdbarch = get_regcache_arch (regcache);
3599 decr_pc = gdbarch_decr_pc_after_break (gdbarch);
3604 pc = regcache_read_pc (regcache);
3605 regcache_write_pc (regcache, pc + decr_pc);
3609 tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON;
3610 *status = tp->suspend.waitstatus;
3611 tp->suspend.waitstatus_pending_p = 0;
3613 /* Wake up the event loop again, until all pending events are
3615 if (target_is_async_p ())
3616 mark_async_event_handler (infrun_async_inferior_event_token);
3620 /* But if we don't find one, we'll have to wait. */
3622 if (deprecated_target_wait_hook)
3623 event_ptid = deprecated_target_wait_hook (ptid, status, options);
3625 event_ptid = target_wait (ptid, status, options);
3630 /* Prepare and stabilize the inferior for detaching it. E.g.,
3631 detaching while a thread is displaced stepping is a recipe for
3632 crashing it, as nothing would readjust the PC out of the scratch
3636 prepare_for_detach (void)
3638 struct inferior *inf = current_inferior ();
3639 ptid_t pid_ptid = pid_to_ptid (inf->pid);
3640 struct displaced_step_inferior_state *displaced;
3642 displaced = get_displaced_stepping_state (inf->pid);
3644 /* Is any thread of this process displaced stepping? If not,
3645 there's nothing else to do. */
3646 if (displaced == NULL || ptid_equal (displaced->step_ptid, null_ptid))
3650 fprintf_unfiltered (gdb_stdlog,
3651 "displaced-stepping in-process while detaching");
3653 scoped_restore restore_detaching = make_scoped_restore (&inf->detaching, true);
3655 while (!ptid_equal (displaced->step_ptid, null_ptid))
3657 struct cleanup *old_chain_2;
3658 struct execution_control_state ecss;
3659 struct execution_control_state *ecs;
3662 memset (ecs, 0, sizeof (*ecs));
3664 overlay_cache_invalid = 1;
3665 /* Flush target cache before starting to handle each event.
3666 Target was running and cache could be stale. This is just a
3667 heuristic. Running threads may modify target memory, but we
3668 don't get any event. */
3669 target_dcache_invalidate ();
3671 ecs->ptid = do_target_wait (pid_ptid, &ecs->ws, 0);
3674 print_target_wait_results (pid_ptid, ecs->ptid, &ecs->ws);
3676 /* If an error happens while handling the event, propagate GDB's
3677 knowledge of the executing state to the frontend/user running
3679 old_chain_2 = make_cleanup (finish_thread_state_cleanup,
3682 /* Now figure out what to do with the result of the result. */
3683 handle_inferior_event (ecs);
3685 /* No error, don't finish the state yet. */
3686 discard_cleanups (old_chain_2);
3688 /* Breakpoints and watchpoints are not installed on the target
3689 at this point, and signals are passed directly to the
3690 inferior, so this must mean the process is gone. */
3691 if (!ecs->wait_some_more)
3693 restore_detaching.release ();
3694 error (_("Program exited while detaching"));
3698 restore_detaching.release ();
3701 /* Wait for control to return from inferior to debugger.
3703 If inferior gets a signal, we may decide to start it up again
3704 instead of returning. That is why there is a loop in this function.
3705 When this function actually returns it means the inferior
3706 should be left stopped and GDB should read more commands. */
3709 wait_for_inferior (void)
3711 struct cleanup *old_cleanups;
3712 struct cleanup *thread_state_chain;
3716 (gdb_stdlog, "infrun: wait_for_inferior ()\n");
3719 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup,
3722 /* If an error happens while handling the event, propagate GDB's
3723 knowledge of the executing state to the frontend/user running
3725 thread_state_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
3729 struct execution_control_state ecss;
3730 struct execution_control_state *ecs = &ecss;
3731 ptid_t waiton_ptid = minus_one_ptid;
3733 memset (ecs, 0, sizeof (*ecs));
3735 overlay_cache_invalid = 1;
3737 /* Flush target cache before starting to handle each event.
3738 Target was running and cache could be stale. This is just a
3739 heuristic. Running threads may modify target memory, but we
3740 don't get any event. */
3741 target_dcache_invalidate ();
3743 ecs->ptid = do_target_wait (waiton_ptid, &ecs->ws, 0);
3746 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
3748 /* Now figure out what to do with the result of the result. */
3749 handle_inferior_event (ecs);
3751 if (!ecs->wait_some_more)
3755 /* No error, don't finish the state yet. */
3756 discard_cleanups (thread_state_chain);
3758 do_cleanups (old_cleanups);
3761 /* Cleanup that reinstalls the readline callback handler, if the
3762 target is running in the background. If while handling the target
3763 event something triggered a secondary prompt, like e.g., a
3764 pagination prompt, we'll have removed the callback handler (see
3765 gdb_readline_wrapper_line). Need to do this as we go back to the
3766 event loop, ready to process further input. Note this has no
3767 effect if the handler hasn't actually been removed, because calling
3768 rl_callback_handler_install resets the line buffer, thus losing
3772 reinstall_readline_callback_handler_cleanup (void *arg)
3774 struct ui *ui = current_ui;
3778 /* We're not going back to the top level event loop yet. Don't
3779 install the readline callback, as it'd prep the terminal,
3780 readline-style (raw, noecho) (e.g., --batch). We'll install
3781 it the next time the prompt is displayed, when we're ready
3786 if (ui->command_editing && ui->prompt_state != PROMPT_BLOCKED)
3787 gdb_rl_callback_handler_reinstall ();
3790 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3791 that's just the event thread. In all-stop, that's all threads. */
3794 clean_up_just_stopped_threads_fsms (struct execution_control_state *ecs)
3796 struct thread_info *thr = ecs->event_thread;
3798 if (thr != NULL && thr->thread_fsm != NULL)
3799 thread_fsm_clean_up (thr->thread_fsm, thr);
3803 ALL_NON_EXITED_THREADS (thr)
3805 if (thr->thread_fsm == NULL)
3807 if (thr == ecs->event_thread)
3810 switch_to_thread (thr->ptid);
3811 thread_fsm_clean_up (thr->thread_fsm, thr);
3814 if (ecs->event_thread != NULL)
3815 switch_to_thread (ecs->event_thread->ptid);
3819 /* Helper for all_uis_check_sync_execution_done that works on the
3823 check_curr_ui_sync_execution_done (void)
3825 struct ui *ui = current_ui;
3827 if (ui->prompt_state == PROMPT_NEEDED
3829 && !gdb_in_secondary_prompt_p (ui))
3831 target_terminal_ours ();
3832 observer_notify_sync_execution_done ();
3833 ui_register_input_event_handler (ui);
3840 all_uis_check_sync_execution_done (void)
3842 SWITCH_THRU_ALL_UIS ()
3844 check_curr_ui_sync_execution_done ();
3851 all_uis_on_sync_execution_starting (void)
3853 SWITCH_THRU_ALL_UIS ()
3855 if (current_ui->prompt_state == PROMPT_NEEDED)
3856 async_disable_stdin ();
3860 /* Asynchronous version of wait_for_inferior. It is called by the
3861 event loop whenever a change of state is detected on the file
3862 descriptor corresponding to the target. It can be called more than
3863 once to complete a single execution command. In such cases we need
3864 to keep the state in a global variable ECSS. If it is the last time
3865 that this function is called for a single execution command, then
3866 report to the user that the inferior has stopped, and do the
3867 necessary cleanups. */
3870 fetch_inferior_event (void *client_data)
3872 struct execution_control_state ecss;
3873 struct execution_control_state *ecs = &ecss;
3874 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
3875 struct cleanup *ts_old_chain;
3877 ptid_t waiton_ptid = minus_one_ptid;
3879 memset (ecs, 0, sizeof (*ecs));
3881 /* Events are always processed with the main UI as current UI. This
3882 way, warnings, debug output, etc. are always consistently sent to
3883 the main console. */
3884 scoped_restore save_ui = make_scoped_restore (¤t_ui, main_ui);
3886 /* End up with readline processing input, if necessary. */
3887 make_cleanup (reinstall_readline_callback_handler_cleanup, NULL);
3889 /* We're handling a live event, so make sure we're doing live
3890 debugging. If we're looking at traceframes while the target is
3891 running, we're going to need to get back to that mode after
3892 handling the event. */
3895 make_cleanup_restore_current_traceframe ();
3896 set_current_traceframe (-1);
3899 gdb::optional<scoped_restore_current_thread> maybe_restore_thread;
3902 /* In non-stop mode, the user/frontend should not notice a thread
3903 switch due to internal events. Make sure we reverse to the
3904 user selected thread and frame after handling the event and
3905 running any breakpoint commands. */
3906 maybe_restore_thread.emplace ();
3908 overlay_cache_invalid = 1;
3909 /* Flush target cache before starting to handle each event. Target
3910 was running and cache could be stale. This is just a heuristic.
3911 Running threads may modify target memory, but we don't get any
3913 target_dcache_invalidate ();
3915 scoped_restore save_exec_dir
3916 = make_scoped_restore (&execution_direction, target_execution_direction ());
3918 ecs->ptid = do_target_wait (waiton_ptid, &ecs->ws,
3919 target_can_async_p () ? TARGET_WNOHANG : 0);
3922 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
3924 /* If an error happens while handling the event, propagate GDB's
3925 knowledge of the executing state to the frontend/user running
3927 if (!target_is_non_stop_p ())
3928 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
3930 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &ecs->ptid);
3932 /* Get executed before make_cleanup_restore_current_thread above to apply
3933 still for the thread which has thrown the exception. */
3934 make_bpstat_clear_actions_cleanup ();
3936 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup, NULL);
3938 /* Now figure out what to do with the result of the result. */
3939 handle_inferior_event (ecs);
3941 if (!ecs->wait_some_more)
3943 struct inferior *inf = find_inferior_ptid (ecs->ptid);
3944 int should_stop = 1;
3945 struct thread_info *thr = ecs->event_thread;
3946 int should_notify_stop = 1;
3948 delete_just_stopped_threads_infrun_breakpoints ();
3952 struct thread_fsm *thread_fsm = thr->thread_fsm;
3954 if (thread_fsm != NULL)
3955 should_stop = thread_fsm_should_stop (thread_fsm, thr);
3964 clean_up_just_stopped_threads_fsms (ecs);
3966 if (thr != NULL && thr->thread_fsm != NULL)
3969 = thread_fsm_should_notify_stop (thr->thread_fsm);
3972 if (should_notify_stop)
3976 /* We may not find an inferior if this was a process exit. */
3977 if (inf == NULL || inf->control.stop_soon == NO_STOP_QUIETLY)
3978 proceeded = normal_stop ();
3982 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
3989 /* No error, don't finish the thread states yet. */
3990 discard_cleanups (ts_old_chain);
3992 /* Revert thread and frame. */
3993 do_cleanups (old_chain);
3995 /* If a UI was in sync execution mode, and now isn't, restore its
3996 prompt (a synchronous execution command has finished, and we're
3997 ready for input). */
3998 all_uis_check_sync_execution_done ();
4001 && exec_done_display_p
4002 && (ptid_equal (inferior_ptid, null_ptid)
4003 || !is_running (inferior_ptid)))
4004 printf_unfiltered (_("completed.\n"));
4007 /* Record the frame and location we're currently stepping through. */
4009 set_step_info (struct frame_info *frame, struct symtab_and_line sal)
4011 struct thread_info *tp = inferior_thread ();
4013 tp->control.step_frame_id = get_frame_id (frame);
4014 tp->control.step_stack_frame_id = get_stack_frame_id (frame);
4016 tp->current_symtab = sal.symtab;
4017 tp->current_line = sal.line;
4020 /* Clear context switchable stepping state. */
4023 init_thread_stepping_state (struct thread_info *tss)
4025 tss->stepped_breakpoint = 0;
4026 tss->stepping_over_breakpoint = 0;
4027 tss->stepping_over_watchpoint = 0;
4028 tss->step_after_step_resume_breakpoint = 0;
4031 /* Set the cached copy of the last ptid/waitstatus. */
4034 set_last_target_status (ptid_t ptid, struct target_waitstatus status)
4036 target_last_wait_ptid = ptid;
4037 target_last_waitstatus = status;
4040 /* Return the cached copy of the last pid/waitstatus returned by
4041 target_wait()/deprecated_target_wait_hook(). The data is actually
4042 cached by handle_inferior_event(), which gets called immediately
4043 after target_wait()/deprecated_target_wait_hook(). */
4046 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
4048 *ptidp = target_last_wait_ptid;
4049 *status = target_last_waitstatus;
4053 nullify_last_target_wait_ptid (void)
4055 target_last_wait_ptid = minus_one_ptid;
4058 /* Switch thread contexts. */
4061 context_switch (ptid_t ptid)
4063 if (debug_infrun && !ptid_equal (ptid, inferior_ptid))
4065 fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ",
4066 target_pid_to_str (inferior_ptid));
4067 fprintf_unfiltered (gdb_stdlog, "to %s\n",
4068 target_pid_to_str (ptid));
4071 switch_to_thread (ptid);
4074 /* If the target can't tell whether we've hit breakpoints
4075 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4076 check whether that could have been caused by a breakpoint. If so,
4077 adjust the PC, per gdbarch_decr_pc_after_break. */
4080 adjust_pc_after_break (struct thread_info *thread,
4081 struct target_waitstatus *ws)
4083 struct regcache *regcache;
4084 struct gdbarch *gdbarch;
4085 struct address_space *aspace;
4086 CORE_ADDR breakpoint_pc, decr_pc;
4088 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4089 we aren't, just return.
4091 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4092 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4093 implemented by software breakpoints should be handled through the normal
4096 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4097 different signals (SIGILL or SIGEMT for instance), but it is less
4098 clear where the PC is pointing afterwards. It may not match
4099 gdbarch_decr_pc_after_break. I don't know any specific target that
4100 generates these signals at breakpoints (the code has been in GDB since at
4101 least 1992) so I can not guess how to handle them here.
4103 In earlier versions of GDB, a target with
4104 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4105 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4106 target with both of these set in GDB history, and it seems unlikely to be
4107 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4109 if (ws->kind != TARGET_WAITKIND_STOPPED)
4112 if (ws->value.sig != GDB_SIGNAL_TRAP)
4115 /* In reverse execution, when a breakpoint is hit, the instruction
4116 under it has already been de-executed. The reported PC always
4117 points at the breakpoint address, so adjusting it further would
4118 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4121 B1 0x08000000 : INSN1
4122 B2 0x08000001 : INSN2
4124 PC -> 0x08000003 : INSN4
4126 Say you're stopped at 0x08000003 as above. Reverse continuing
4127 from that point should hit B2 as below. Reading the PC when the
4128 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4129 been de-executed already.
4131 B1 0x08000000 : INSN1
4132 B2 PC -> 0x08000001 : INSN2
4136 We can't apply the same logic as for forward execution, because
4137 we would wrongly adjust the PC to 0x08000000, since there's a
4138 breakpoint at PC - 1. We'd then report a hit on B1, although
4139 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4141 if (execution_direction == EXEC_REVERSE)
4144 /* If the target can tell whether the thread hit a SW breakpoint,
4145 trust it. Targets that can tell also adjust the PC
4147 if (target_supports_stopped_by_sw_breakpoint ())
4150 /* Note that relying on whether a breakpoint is planted in memory to
4151 determine this can fail. E.g,. the breakpoint could have been
4152 removed since. Or the thread could have been told to step an
4153 instruction the size of a breakpoint instruction, and only
4154 _after_ was a breakpoint inserted at its address. */
4156 /* If this target does not decrement the PC after breakpoints, then
4157 we have nothing to do. */
4158 regcache = get_thread_regcache (thread->ptid);
4159 gdbarch = get_regcache_arch (regcache);
4161 decr_pc = gdbarch_decr_pc_after_break (gdbarch);
4165 aspace = get_regcache_aspace (regcache);
4167 /* Find the location where (if we've hit a breakpoint) the
4168 breakpoint would be. */
4169 breakpoint_pc = regcache_read_pc (regcache) - decr_pc;
4171 /* If the target can't tell whether a software breakpoint triggered,
4172 fallback to figuring it out based on breakpoints we think were
4173 inserted in the target, and on whether the thread was stepped or
4176 /* Check whether there actually is a software breakpoint inserted at
4179 If in non-stop mode, a race condition is possible where we've
4180 removed a breakpoint, but stop events for that breakpoint were
4181 already queued and arrive later. To suppress those spurious
4182 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4183 and retire them after a number of stop events are reported. Note
4184 this is an heuristic and can thus get confused. The real fix is
4185 to get the "stopped by SW BP and needs adjustment" info out of
4186 the target/kernel (and thus never reach here; see above). */
4187 if (software_breakpoint_inserted_here_p (aspace, breakpoint_pc)
4188 || (target_is_non_stop_p ()
4189 && moribund_breakpoint_here_p (aspace, breakpoint_pc)))
4191 struct cleanup *old_cleanups = make_cleanup (null_cleanup, NULL);
4193 if (record_full_is_used ())
4194 record_full_gdb_operation_disable_set ();
4196 /* When using hardware single-step, a SIGTRAP is reported for both
4197 a completed single-step and a software breakpoint. Need to
4198 differentiate between the two, as the latter needs adjusting
4199 but the former does not.
4201 The SIGTRAP can be due to a completed hardware single-step only if
4202 - we didn't insert software single-step breakpoints
4203 - this thread is currently being stepped
4205 If any of these events did not occur, we must have stopped due
4206 to hitting a software breakpoint, and have to back up to the
4209 As a special case, we could have hardware single-stepped a
4210 software breakpoint. In this case (prev_pc == breakpoint_pc),
4211 we also need to back up to the breakpoint address. */
4213 if (thread_has_single_step_breakpoints_set (thread)
4214 || !currently_stepping (thread)
4215 || (thread->stepped_breakpoint
4216 && thread->prev_pc == breakpoint_pc))
4217 regcache_write_pc (regcache, breakpoint_pc);
4219 do_cleanups (old_cleanups);
4224 stepped_in_from (struct frame_info *frame, struct frame_id step_frame_id)
4226 for (frame = get_prev_frame (frame);
4228 frame = get_prev_frame (frame))
4230 if (frame_id_eq (get_frame_id (frame), step_frame_id))
4232 if (get_frame_type (frame) != INLINE_FRAME)
4239 /* If the event thread has the stop requested flag set, pretend it
4240 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4244 handle_stop_requested (struct execution_control_state *ecs)
4246 if (ecs->event_thread->stop_requested)
4248 ecs->ws.kind = TARGET_WAITKIND_STOPPED;
4249 ecs->ws.value.sig = GDB_SIGNAL_0;
4250 handle_signal_stop (ecs);
4256 /* Auxiliary function that handles syscall entry/return events.
4257 It returns 1 if the inferior should keep going (and GDB
4258 should ignore the event), or 0 if the event deserves to be
4262 handle_syscall_event (struct execution_control_state *ecs)
4264 struct regcache *regcache;
4267 if (!ptid_equal (ecs->ptid, inferior_ptid))
4268 context_switch (ecs->ptid);
4270 regcache = get_thread_regcache (ecs->ptid);
4271 syscall_number = ecs->ws.value.syscall_number;
4272 stop_pc = regcache_read_pc (regcache);
4274 if (catch_syscall_enabled () > 0
4275 && catching_syscall_number (syscall_number) > 0)
4278 fprintf_unfiltered (gdb_stdlog, "infrun: syscall number = '%d'\n",
4281 ecs->event_thread->control.stop_bpstat
4282 = bpstat_stop_status (get_regcache_aspace (regcache),
4283 stop_pc, ecs->ptid, &ecs->ws);
4285 if (handle_stop_requested (ecs))
4288 if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
4290 /* Catchpoint hit. */
4295 if (handle_stop_requested (ecs))
4298 /* If no catchpoint triggered for this, then keep going. */
4303 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4306 fill_in_stop_func (struct gdbarch *gdbarch,
4307 struct execution_control_state *ecs)
4309 if (!ecs->stop_func_filled_in)
4311 /* Don't care about return value; stop_func_start and stop_func_name
4312 will both be 0 if it doesn't work. */
4313 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
4314 &ecs->stop_func_start, &ecs->stop_func_end);
4315 ecs->stop_func_start
4316 += gdbarch_deprecated_function_start_offset (gdbarch);
4318 if (gdbarch_skip_entrypoint_p (gdbarch))
4319 ecs->stop_func_start = gdbarch_skip_entrypoint (gdbarch,
4320 ecs->stop_func_start);
4322 ecs->stop_func_filled_in = 1;
4327 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4329 static enum stop_kind
4330 get_inferior_stop_soon (ptid_t ptid)
4332 struct inferior *inf = find_inferior_ptid (ptid);
4334 gdb_assert (inf != NULL);
4335 return inf->control.stop_soon;
4338 /* Wait for one event. Store the resulting waitstatus in WS, and
4339 return the event ptid. */
4342 wait_one (struct target_waitstatus *ws)
4345 ptid_t wait_ptid = minus_one_ptid;
4347 overlay_cache_invalid = 1;
4349 /* Flush target cache before starting to handle each event.
4350 Target was running and cache could be stale. This is just a
4351 heuristic. Running threads may modify target memory, but we
4352 don't get any event. */
4353 target_dcache_invalidate ();
4355 if (deprecated_target_wait_hook)
4356 event_ptid = deprecated_target_wait_hook (wait_ptid, ws, 0);
4358 event_ptid = target_wait (wait_ptid, ws, 0);
4361 print_target_wait_results (wait_ptid, event_ptid, ws);
4366 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4367 instead of the current thread. */
4368 #define THREAD_STOPPED_BY(REASON) \
4370 thread_stopped_by_ ## REASON (ptid_t ptid) \
4372 struct cleanup *old_chain; \
4375 old_chain = save_inferior_ptid (); \
4376 inferior_ptid = ptid; \
4378 res = target_stopped_by_ ## REASON (); \
4380 do_cleanups (old_chain); \
4385 /* Generate thread_stopped_by_watchpoint. */
4386 THREAD_STOPPED_BY (watchpoint)
4387 /* Generate thread_stopped_by_sw_breakpoint. */
4388 THREAD_STOPPED_BY (sw_breakpoint)
4389 /* Generate thread_stopped_by_hw_breakpoint. */
4390 THREAD_STOPPED_BY (hw_breakpoint)
4392 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4395 switch_to_thread_cleanup (void *ptid_p)
4397 ptid_t ptid = *(ptid_t *) ptid_p;
4399 switch_to_thread (ptid);
4402 /* Save the thread's event and stop reason to process it later. */
4405 save_waitstatus (struct thread_info *tp, struct target_waitstatus *ws)
4407 struct regcache *regcache;
4408 struct address_space *aspace;
4414 statstr = target_waitstatus_to_string (ws);
4415 fprintf_unfiltered (gdb_stdlog,
4416 "infrun: saving status %s for %d.%ld.%ld\n",
4418 ptid_get_pid (tp->ptid),
4419 ptid_get_lwp (tp->ptid),
4420 ptid_get_tid (tp->ptid));
4424 /* Record for later. */
4425 tp->suspend.waitstatus = *ws;
4426 tp->suspend.waitstatus_pending_p = 1;
4428 regcache = get_thread_regcache (tp->ptid);
4429 aspace = get_regcache_aspace (regcache);
4431 if (ws->kind == TARGET_WAITKIND_STOPPED
4432 && ws->value.sig == GDB_SIGNAL_TRAP)
4434 CORE_ADDR pc = regcache_read_pc (regcache);
4436 adjust_pc_after_break (tp, &tp->suspend.waitstatus);
4438 if (thread_stopped_by_watchpoint (tp->ptid))
4440 tp->suspend.stop_reason
4441 = TARGET_STOPPED_BY_WATCHPOINT;
4443 else if (target_supports_stopped_by_sw_breakpoint ()
4444 && thread_stopped_by_sw_breakpoint (tp->ptid))
4446 tp->suspend.stop_reason
4447 = TARGET_STOPPED_BY_SW_BREAKPOINT;
4449 else if (target_supports_stopped_by_hw_breakpoint ()
4450 && thread_stopped_by_hw_breakpoint (tp->ptid))
4452 tp->suspend.stop_reason
4453 = TARGET_STOPPED_BY_HW_BREAKPOINT;
4455 else if (!target_supports_stopped_by_hw_breakpoint ()
4456 && hardware_breakpoint_inserted_here_p (aspace,
4459 tp->suspend.stop_reason
4460 = TARGET_STOPPED_BY_HW_BREAKPOINT;
4462 else if (!target_supports_stopped_by_sw_breakpoint ()
4463 && software_breakpoint_inserted_here_p (aspace,
4466 tp->suspend.stop_reason
4467 = TARGET_STOPPED_BY_SW_BREAKPOINT;
4469 else if (!thread_has_single_step_breakpoints_set (tp)
4470 && currently_stepping (tp))
4472 tp->suspend.stop_reason
4473 = TARGET_STOPPED_BY_SINGLE_STEP;
4478 /* A cleanup that disables thread create/exit events. */
4481 disable_thread_events (void *arg)
4483 target_thread_events (0);
4489 stop_all_threads (void)
4491 /* We may need multiple passes to discover all threads. */
4495 struct cleanup *old_chain;
4497 gdb_assert (target_is_non_stop_p ());
4500 fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads\n");
4502 entry_ptid = inferior_ptid;
4503 old_chain = make_cleanup (switch_to_thread_cleanup, &entry_ptid);
4505 target_thread_events (1);
4506 make_cleanup (disable_thread_events, NULL);
4508 /* Request threads to stop, and then wait for the stops. Because
4509 threads we already know about can spawn more threads while we're
4510 trying to stop them, and we only learn about new threads when we
4511 update the thread list, do this in a loop, and keep iterating
4512 until two passes find no threads that need to be stopped. */
4513 for (pass = 0; pass < 2; pass++, iterations++)
4516 fprintf_unfiltered (gdb_stdlog,
4517 "infrun: stop_all_threads, pass=%d, "
4518 "iterations=%d\n", pass, iterations);
4522 struct target_waitstatus ws;
4524 struct thread_info *t;
4526 update_thread_list ();
4528 /* Go through all threads looking for threads that we need
4529 to tell the target to stop. */
4530 ALL_NON_EXITED_THREADS (t)
4534 /* If already stopping, don't request a stop again.
4535 We just haven't seen the notification yet. */
4536 if (!t->stop_requested)
4539 fprintf_unfiltered (gdb_stdlog,
4540 "infrun: %s executing, "
4542 target_pid_to_str (t->ptid));
4543 target_stop (t->ptid);
4544 t->stop_requested = 1;
4549 fprintf_unfiltered (gdb_stdlog,
4550 "infrun: %s executing, "
4551 "already stopping\n",
4552 target_pid_to_str (t->ptid));
4555 if (t->stop_requested)
4561 fprintf_unfiltered (gdb_stdlog,
4562 "infrun: %s not executing\n",
4563 target_pid_to_str (t->ptid));
4565 /* The thread may be not executing, but still be
4566 resumed with a pending status to process. */
4574 /* If we find new threads on the second iteration, restart
4575 over. We want to see two iterations in a row with all
4580 event_ptid = wait_one (&ws);
4581 if (ws.kind == TARGET_WAITKIND_NO_RESUMED)
4583 /* All resumed threads exited. */
4585 else if (ws.kind == TARGET_WAITKIND_THREAD_EXITED
4586 || ws.kind == TARGET_WAITKIND_EXITED
4587 || ws.kind == TARGET_WAITKIND_SIGNALLED)
4591 ptid_t ptid = pid_to_ptid (ws.value.integer);
4593 fprintf_unfiltered (gdb_stdlog,
4594 "infrun: %s exited while "
4595 "stopping threads\n",
4596 target_pid_to_str (ptid));
4601 struct inferior *inf;
4603 t = find_thread_ptid (event_ptid);
4605 t = add_thread (event_ptid);
4607 t->stop_requested = 0;
4610 t->control.may_range_step = 0;
4612 /* This may be the first time we see the inferior report
4614 inf = find_inferior_ptid (event_ptid);
4615 if (inf->needs_setup)
4617 switch_to_thread_no_regs (t);
4621 if (ws.kind == TARGET_WAITKIND_STOPPED
4622 && ws.value.sig == GDB_SIGNAL_0)
4624 /* We caught the event that we intended to catch, so
4625 there's no event pending. */
4626 t->suspend.waitstatus.kind = TARGET_WAITKIND_IGNORE;
4627 t->suspend.waitstatus_pending_p = 0;
4629 if (displaced_step_fixup (t->ptid, GDB_SIGNAL_0) < 0)
4631 /* Add it back to the step-over queue. */
4634 fprintf_unfiltered (gdb_stdlog,
4635 "infrun: displaced-step of %s "
4636 "canceled: adding back to the "
4637 "step-over queue\n",
4638 target_pid_to_str (t->ptid));
4640 t->control.trap_expected = 0;
4641 thread_step_over_chain_enqueue (t);
4646 enum gdb_signal sig;
4647 struct regcache *regcache;
4653 statstr = target_waitstatus_to_string (&ws);
4654 fprintf_unfiltered (gdb_stdlog,
4655 "infrun: target_wait %s, saving "
4656 "status for %d.%ld.%ld\n",
4658 ptid_get_pid (t->ptid),
4659 ptid_get_lwp (t->ptid),
4660 ptid_get_tid (t->ptid));
4664 /* Record for later. */
4665 save_waitstatus (t, &ws);
4667 sig = (ws.kind == TARGET_WAITKIND_STOPPED
4668 ? ws.value.sig : GDB_SIGNAL_0);
4670 if (displaced_step_fixup (t->ptid, sig) < 0)
4672 /* Add it back to the step-over queue. */
4673 t->control.trap_expected = 0;
4674 thread_step_over_chain_enqueue (t);
4677 regcache = get_thread_regcache (t->ptid);
4678 t->suspend.stop_pc = regcache_read_pc (regcache);
4682 fprintf_unfiltered (gdb_stdlog,
4683 "infrun: saved stop_pc=%s for %s "
4684 "(currently_stepping=%d)\n",
4685 paddress (target_gdbarch (),
4686 t->suspend.stop_pc),
4687 target_pid_to_str (t->ptid),
4688 currently_stepping (t));
4695 do_cleanups (old_chain);
4698 fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads done\n");
4701 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4704 handle_no_resumed (struct execution_control_state *ecs)
4706 struct inferior *inf;
4707 struct thread_info *thread;
4709 if (target_can_async_p ())
4716 if (ui->prompt_state == PROMPT_BLOCKED)
4724 /* There were no unwaited-for children left in the target, but,
4725 we're not synchronously waiting for events either. Just
4729 fprintf_unfiltered (gdb_stdlog,
4730 "infrun: TARGET_WAITKIND_NO_RESUMED "
4731 "(ignoring: bg)\n");
4732 prepare_to_wait (ecs);
4737 /* Otherwise, if we were running a synchronous execution command, we
4738 may need to cancel it and give the user back the terminal.
4740 In non-stop mode, the target can't tell whether we've already
4741 consumed previous stop events, so it can end up sending us a
4742 no-resumed event like so:
4744 #0 - thread 1 is left stopped
4746 #1 - thread 2 is resumed and hits breakpoint
4747 -> TARGET_WAITKIND_STOPPED
4749 #2 - thread 3 is resumed and exits
4750 this is the last resumed thread, so
4751 -> TARGET_WAITKIND_NO_RESUMED
4753 #3 - gdb processes stop for thread 2 and decides to re-resume
4756 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4757 thread 2 is now resumed, so the event should be ignored.
4759 IOW, if the stop for thread 2 doesn't end a foreground command,
4760 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4761 event. But it could be that the event meant that thread 2 itself
4762 (or whatever other thread was the last resumed thread) exited.
4764 To address this we refresh the thread list and check whether we
4765 have resumed threads _now_. In the example above, this removes
4766 thread 3 from the thread list. If thread 2 was re-resumed, we
4767 ignore this event. If we find no thread resumed, then we cancel
4768 the synchronous command show "no unwaited-for " to the user. */
4769 update_thread_list ();
4771 ALL_NON_EXITED_THREADS (thread)
4773 if (thread->executing
4774 || thread->suspend.waitstatus_pending_p)
4776 /* There were no unwaited-for children left in the target at
4777 some point, but there are now. Just ignore. */
4779 fprintf_unfiltered (gdb_stdlog,
4780 "infrun: TARGET_WAITKIND_NO_RESUMED "
4781 "(ignoring: found resumed)\n");
4782 prepare_to_wait (ecs);
4787 /* Note however that we may find no resumed thread because the whole
4788 process exited meanwhile (thus updating the thread list results
4789 in an empty thread list). In this case we know we'll be getting
4790 a process exit event shortly. */
4796 thread = any_live_thread_of_process (inf->pid);
4800 fprintf_unfiltered (gdb_stdlog,
4801 "infrun: TARGET_WAITKIND_NO_RESUMED "
4802 "(expect process exit)\n");
4803 prepare_to_wait (ecs);
4808 /* Go ahead and report the event. */
4812 /* Given an execution control state that has been freshly filled in by
4813 an event from the inferior, figure out what it means and take
4816 The alternatives are:
4818 1) stop_waiting and return; to really stop and return to the
4821 2) keep_going and return; to wait for the next event (set
4822 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4826 handle_inferior_event_1 (struct execution_control_state *ecs)
4828 enum stop_kind stop_soon;
4830 if (ecs->ws.kind == TARGET_WAITKIND_IGNORE)
4832 /* We had an event in the inferior, but we are not interested in
4833 handling it at this level. The lower layers have already
4834 done what needs to be done, if anything.
4836 One of the possible circumstances for this is when the
4837 inferior produces output for the console. The inferior has
4838 not stopped, and we are ignoring the event. Another possible
4839 circumstance is any event which the lower level knows will be
4840 reported multiple times without an intervening resume. */
4842 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n");
4843 prepare_to_wait (ecs);
4847 if (ecs->ws.kind == TARGET_WAITKIND_THREAD_EXITED)
4850 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4851 prepare_to_wait (ecs);
4855 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED
4856 && handle_no_resumed (ecs))
4859 /* Cache the last pid/waitstatus. */
4860 set_last_target_status (ecs->ptid, ecs->ws);
4862 /* Always clear state belonging to the previous time we stopped. */
4863 stop_stack_dummy = STOP_NONE;
4865 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED)
4867 /* No unwaited-for children left. IOW, all resumed children
4870 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4872 stop_print_frame = 0;
4877 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
4878 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
4880 ecs->event_thread = find_thread_ptid (ecs->ptid);
4881 /* If it's a new thread, add it to the thread database. */
4882 if (ecs->event_thread == NULL)
4883 ecs->event_thread = add_thread (ecs->ptid);
4885 /* Disable range stepping. If the next step request could use a
4886 range, this will be end up re-enabled then. */
4887 ecs->event_thread->control.may_range_step = 0;
4890 /* Dependent on valid ECS->EVENT_THREAD. */
4891 adjust_pc_after_break (ecs->event_thread, &ecs->ws);
4893 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4894 reinit_frame_cache ();
4896 breakpoint_retire_moribund ();
4898 /* First, distinguish signals caused by the debugger from signals
4899 that have to do with the program's own actions. Note that
4900 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4901 on the operating system version. Here we detect when a SIGILL or
4902 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4903 something similar for SIGSEGV, since a SIGSEGV will be generated
4904 when we're trying to execute a breakpoint instruction on a
4905 non-executable stack. This happens for call dummy breakpoints
4906 for architectures like SPARC that place call dummies on the
4908 if (ecs->ws.kind == TARGET_WAITKIND_STOPPED
4909 && (ecs->ws.value.sig == GDB_SIGNAL_ILL
4910 || ecs->ws.value.sig == GDB_SIGNAL_SEGV
4911 || ecs->ws.value.sig == GDB_SIGNAL_EMT))
4913 struct regcache *regcache = get_thread_regcache (ecs->ptid);
4915 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache),
4916 regcache_read_pc (regcache)))
4919 fprintf_unfiltered (gdb_stdlog,
4920 "infrun: Treating signal as SIGTRAP\n");
4921 ecs->ws.value.sig = GDB_SIGNAL_TRAP;
4925 /* Mark the non-executing threads accordingly. In all-stop, all
4926 threads of all processes are stopped when we get any event
4927 reported. In non-stop mode, only the event thread stops. */
4931 if (!target_is_non_stop_p ())
4932 mark_ptid = minus_one_ptid;
4933 else if (ecs->ws.kind == TARGET_WAITKIND_SIGNALLED
4934 || ecs->ws.kind == TARGET_WAITKIND_EXITED)
4936 /* If we're handling a process exit in non-stop mode, even
4937 though threads haven't been deleted yet, one would think
4938 that there is nothing to do, as threads of the dead process
4939 will be soon deleted, and threads of any other process were
4940 left running. However, on some targets, threads survive a
4941 process exit event. E.g., for the "checkpoint" command,
4942 when the current checkpoint/fork exits, linux-fork.c
4943 automatically switches to another fork from within
4944 target_mourn_inferior, by associating the same
4945 inferior/thread to another fork. We haven't mourned yet at
4946 this point, but we must mark any threads left in the
4947 process as not-executing so that finish_thread_state marks
4948 them stopped (in the user's perspective) if/when we present
4949 the stop to the user. */
4950 mark_ptid = pid_to_ptid (ptid_get_pid (ecs->ptid));
4953 mark_ptid = ecs->ptid;
4955 set_executing (mark_ptid, 0);
4957 /* Likewise the resumed flag. */
4958 set_resumed (mark_ptid, 0);
4961 switch (ecs->ws.kind)
4963 case TARGET_WAITKIND_LOADED:
4965 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n");
4966 if (!ptid_equal (ecs->ptid, inferior_ptid))
4967 context_switch (ecs->ptid);
4968 /* Ignore gracefully during startup of the inferior, as it might
4969 be the shell which has just loaded some objects, otherwise
4970 add the symbols for the newly loaded objects. Also ignore at
4971 the beginning of an attach or remote session; we will query
4972 the full list of libraries once the connection is
4975 stop_soon = get_inferior_stop_soon (ecs->ptid);
4976 if (stop_soon == NO_STOP_QUIETLY)
4978 struct regcache *regcache;
4980 regcache = get_thread_regcache (ecs->ptid);
4982 handle_solib_event ();
4984 ecs->event_thread->control.stop_bpstat
4985 = bpstat_stop_status (get_regcache_aspace (regcache),
4986 stop_pc, ecs->ptid, &ecs->ws);
4988 if (handle_stop_requested (ecs))
4991 if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
4993 /* A catchpoint triggered. */
4994 process_event_stop_test (ecs);
4998 /* If requested, stop when the dynamic linker notifies
4999 gdb of events. This allows the user to get control
5000 and place breakpoints in initializer routines for
5001 dynamically loaded objects (among other things). */
5002 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5003 if (stop_on_solib_events)
5005 /* Make sure we print "Stopped due to solib-event" in
5007 stop_print_frame = 1;
5014 /* If we are skipping through a shell, or through shared library
5015 loading that we aren't interested in, resume the program. If
5016 we're running the program normally, also resume. */
5017 if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY)
5019 /* Loading of shared libraries might have changed breakpoint
5020 addresses. Make sure new breakpoints are inserted. */
5021 if (stop_soon == NO_STOP_QUIETLY)
5022 insert_breakpoints ();
5023 resume (GDB_SIGNAL_0);
5024 prepare_to_wait (ecs);
5028 /* But stop if we're attaching or setting up a remote
5030 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
5031 || stop_soon == STOP_QUIETLY_REMOTE)
5034 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
5039 internal_error (__FILE__, __LINE__,
5040 _("unhandled stop_soon: %d"), (int) stop_soon);
5042 case TARGET_WAITKIND_SPURIOUS:
5044 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
5045 if (handle_stop_requested (ecs))
5047 if (!ptid_equal (ecs->ptid, inferior_ptid))
5048 context_switch (ecs->ptid);
5049 resume (GDB_SIGNAL_0);
5050 prepare_to_wait (ecs);
5053 case TARGET_WAITKIND_THREAD_CREATED:
5055 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
5056 if (handle_stop_requested (ecs))
5058 if (!ptid_equal (ecs->ptid, inferior_ptid))
5059 context_switch (ecs->ptid);
5060 if (!switch_back_to_stepped_thread (ecs))
5064 case TARGET_WAITKIND_EXITED:
5065 case TARGET_WAITKIND_SIGNALLED:
5068 if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
5069 fprintf_unfiltered (gdb_stdlog,
5070 "infrun: TARGET_WAITKIND_EXITED\n");
5072 fprintf_unfiltered (gdb_stdlog,
5073 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5076 inferior_ptid = ecs->ptid;
5077 set_current_inferior (find_inferior_ptid (ecs->ptid));
5078 set_current_program_space (current_inferior ()->pspace);
5079 handle_vfork_child_exec_or_exit (0);
5080 target_terminal_ours (); /* Must do this before mourn anyway. */
5082 /* Clearing any previous state of convenience variables. */
5083 clear_exit_convenience_vars ();
5085 if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
5087 /* Record the exit code in the convenience variable $_exitcode, so
5088 that the user can inspect this again later. */
5089 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5090 (LONGEST) ecs->ws.value.integer);
5092 /* Also record this in the inferior itself. */
5093 current_inferior ()->has_exit_code = 1;
5094 current_inferior ()->exit_code = (LONGEST) ecs->ws.value.integer;
5096 /* Support the --return-child-result option. */
5097 return_child_result_value = ecs->ws.value.integer;
5099 observer_notify_exited (ecs->ws.value.integer);
5103 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5104 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5106 if (gdbarch_gdb_signal_to_target_p (gdbarch))
5108 /* Set the value of the internal variable $_exitsignal,
5109 which holds the signal uncaught by the inferior. */
5110 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5111 gdbarch_gdb_signal_to_target (gdbarch,
5112 ecs->ws.value.sig));
5116 /* We don't have access to the target's method used for
5117 converting between signal numbers (GDB's internal
5118 representation <-> target's representation).
5119 Therefore, we cannot do a good job at displaying this
5120 information to the user. It's better to just warn
5121 her about it (if infrun debugging is enabled), and
5124 fprintf_filtered (gdb_stdlog, _("\
5125 Cannot fill $_exitsignal with the correct signal number.\n"));
5128 observer_notify_signal_exited (ecs->ws.value.sig);
5131 gdb_flush (gdb_stdout);
5132 target_mourn_inferior (inferior_ptid);
5133 stop_print_frame = 0;
5137 /* The following are the only cases in which we keep going;
5138 the above cases end in a continue or goto. */
5139 case TARGET_WAITKIND_FORKED:
5140 case TARGET_WAITKIND_VFORKED:
5143 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
5144 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
5146 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_VFORKED\n");
5149 /* Check whether the inferior is displaced stepping. */
5151 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5152 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5154 /* If checking displaced stepping is supported, and thread
5155 ecs->ptid is displaced stepping. */
5156 if (displaced_step_in_progress_thread (ecs->ptid))
5158 struct inferior *parent_inf
5159 = find_inferior_ptid (ecs->ptid);
5160 struct regcache *child_regcache;
5161 CORE_ADDR parent_pc;
5163 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5164 indicating that the displaced stepping of syscall instruction
5165 has been done. Perform cleanup for parent process here. Note
5166 that this operation also cleans up the child process for vfork,
5167 because their pages are shared. */
5168 displaced_step_fixup (ecs->ptid, GDB_SIGNAL_TRAP);
5169 /* Start a new step-over in another thread if there's one
5173 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
5175 struct displaced_step_inferior_state *displaced
5176 = get_displaced_stepping_state (ptid_get_pid (ecs->ptid));
5178 /* Restore scratch pad for child process. */
5179 displaced_step_restore (displaced, ecs->ws.value.related_pid);
5182 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5183 the child's PC is also within the scratchpad. Set the child's PC
5184 to the parent's PC value, which has already been fixed up.
5185 FIXME: we use the parent's aspace here, although we're touching
5186 the child, because the child hasn't been added to the inferior
5187 list yet at this point. */
5190 = get_thread_arch_aspace_regcache (ecs->ws.value.related_pid,
5192 parent_inf->aspace);
5193 /* Read PC value of parent process. */
5194 parent_pc = regcache_read_pc (regcache);
5196 if (debug_displaced)
5197 fprintf_unfiltered (gdb_stdlog,
5198 "displaced: write child pc from %s to %s\n",
5200 regcache_read_pc (child_regcache)),
5201 paddress (gdbarch, parent_pc));
5203 regcache_write_pc (child_regcache, parent_pc);
5207 if (!ptid_equal (ecs->ptid, inferior_ptid))
5208 context_switch (ecs->ptid);
5210 /* Immediately detach breakpoints from the child before there's
5211 any chance of letting the user delete breakpoints from the
5212 breakpoint lists. If we don't do this early, it's easy to
5213 leave left over traps in the child, vis: "break foo; catch
5214 fork; c; <fork>; del; c; <child calls foo>". We only follow
5215 the fork on the last `continue', and by that time the
5216 breakpoint at "foo" is long gone from the breakpoint table.
5217 If we vforked, then we don't need to unpatch here, since both
5218 parent and child are sharing the same memory pages; we'll
5219 need to unpatch at follow/detach time instead to be certain
5220 that new breakpoints added between catchpoint hit time and
5221 vfork follow are detached. */
5222 if (ecs->ws.kind != TARGET_WAITKIND_VFORKED)
5224 /* This won't actually modify the breakpoint list, but will
5225 physically remove the breakpoints from the child. */
5226 detach_breakpoints (ecs->ws.value.related_pid);
5229 delete_just_stopped_threads_single_step_breakpoints ();
5231 /* In case the event is caught by a catchpoint, remember that
5232 the event is to be followed at the next resume of the thread,
5233 and not immediately. */
5234 ecs->event_thread->pending_follow = ecs->ws;
5236 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5238 ecs->event_thread->control.stop_bpstat
5239 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5240 stop_pc, ecs->ptid, &ecs->ws);
5242 if (handle_stop_requested (ecs))
5245 /* If no catchpoint triggered for this, then keep going. Note
5246 that we're interested in knowing the bpstat actually causes a
5247 stop, not just if it may explain the signal. Software
5248 watchpoints, for example, always appear in the bpstat. */
5249 if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
5255 = (follow_fork_mode_string == follow_fork_mode_child);
5257 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5259 should_resume = follow_fork ();
5262 child = ecs->ws.value.related_pid;
5264 /* At this point, the parent is marked running, and the
5265 child is marked stopped. */
5267 /* If not resuming the parent, mark it stopped. */
5268 if (follow_child && !detach_fork && !non_stop && !sched_multi)
5269 set_running (parent, 0);
5271 /* If resuming the child, mark it running. */
5272 if (follow_child || (!detach_fork && (non_stop || sched_multi)))
5273 set_running (child, 1);
5275 /* In non-stop mode, also resume the other branch. */
5276 if (!detach_fork && (non_stop
5277 || (sched_multi && target_is_non_stop_p ())))
5280 switch_to_thread (parent);
5282 switch_to_thread (child);
5284 ecs->event_thread = inferior_thread ();
5285 ecs->ptid = inferior_ptid;
5290 switch_to_thread (child);
5292 switch_to_thread (parent);
5294 ecs->event_thread = inferior_thread ();
5295 ecs->ptid = inferior_ptid;
5303 process_event_stop_test (ecs);
5306 case TARGET_WAITKIND_VFORK_DONE:
5307 /* Done with the shared memory region. Re-insert breakpoints in
5308 the parent, and keep going. */
5311 fprintf_unfiltered (gdb_stdlog,
5312 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5314 if (!ptid_equal (ecs->ptid, inferior_ptid))
5315 context_switch (ecs->ptid);
5317 current_inferior ()->waiting_for_vfork_done = 0;
5318 current_inferior ()->pspace->breakpoints_not_allowed = 0;
5320 if (handle_stop_requested (ecs))
5323 /* This also takes care of reinserting breakpoints in the
5324 previously locked inferior. */
5328 case TARGET_WAITKIND_EXECD:
5330 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n");
5332 if (!ptid_equal (ecs->ptid, inferior_ptid))
5333 context_switch (ecs->ptid);
5335 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5337 /* Do whatever is necessary to the parent branch of the vfork. */
5338 handle_vfork_child_exec_or_exit (1);
5340 /* This causes the eventpoints and symbol table to be reset.
5341 Must do this now, before trying to determine whether to
5343 follow_exec (inferior_ptid, ecs->ws.value.execd_pathname);
5345 /* In follow_exec we may have deleted the original thread and
5346 created a new one. Make sure that the event thread is the
5347 execd thread for that case (this is a nop otherwise). */
5348 ecs->event_thread = inferior_thread ();
5350 ecs->event_thread->control.stop_bpstat
5351 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5352 stop_pc, ecs->ptid, &ecs->ws);
5354 /* Note that this may be referenced from inside
5355 bpstat_stop_status above, through inferior_has_execd. */
5356 xfree (ecs->ws.value.execd_pathname);
5357 ecs->ws.value.execd_pathname = NULL;
5359 if (handle_stop_requested (ecs))
5362 /* If no catchpoint triggered for this, then keep going. */
5363 if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
5365 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5369 process_event_stop_test (ecs);
5372 /* Be careful not to try to gather much state about a thread
5373 that's in a syscall. It's frequently a losing proposition. */
5374 case TARGET_WAITKIND_SYSCALL_ENTRY:
5376 fprintf_unfiltered (gdb_stdlog,
5377 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5378 /* Getting the current syscall number. */
5379 if (handle_syscall_event (ecs) == 0)
5380 process_event_stop_test (ecs);
5383 /* Before examining the threads further, step this thread to
5384 get it entirely out of the syscall. (We get notice of the
5385 event when the thread is just on the verge of exiting a
5386 syscall. Stepping one instruction seems to get it back
5388 case TARGET_WAITKIND_SYSCALL_RETURN:
5390 fprintf_unfiltered (gdb_stdlog,
5391 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5392 if (handle_syscall_event (ecs) == 0)
5393 process_event_stop_test (ecs);
5396 case TARGET_WAITKIND_STOPPED:
5398 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n");
5399 handle_signal_stop (ecs);
5402 case TARGET_WAITKIND_NO_HISTORY:
5404 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5405 /* Reverse execution: target ran out of history info. */
5407 /* Switch to the stopped thread. */
5408 if (!ptid_equal (ecs->ptid, inferior_ptid))
5409 context_switch (ecs->ptid);
5411 fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n");
5413 delete_just_stopped_threads_single_step_breakpoints ();
5414 stop_pc = regcache_read_pc (get_thread_regcache (inferior_ptid));
5416 if (handle_stop_requested (ecs))
5419 observer_notify_no_history ();
5425 /* A wrapper around handle_inferior_event_1, which also makes sure
5426 that all temporary struct value objects that were created during
5427 the handling of the event get deleted at the end. */
5430 handle_inferior_event (struct execution_control_state *ecs)
5432 struct value *mark = value_mark ();
5434 handle_inferior_event_1 (ecs);
5435 /* Purge all temporary values created during the event handling,
5436 as it could be a long time before we return to the command level
5437 where such values would otherwise be purged. */
5438 value_free_to_mark (mark);
5441 /* Restart threads back to what they were trying to do back when we
5442 paused them for an in-line step-over. The EVENT_THREAD thread is
5446 restart_threads (struct thread_info *event_thread)
5448 struct thread_info *tp;
5450 /* In case the instruction just stepped spawned a new thread. */
5451 update_thread_list ();
5453 ALL_NON_EXITED_THREADS (tp)
5455 if (tp == event_thread)
5458 fprintf_unfiltered (gdb_stdlog,
5459 "infrun: restart threads: "
5460 "[%s] is event thread\n",
5461 target_pid_to_str (tp->ptid));
5465 if (!(tp->state == THREAD_RUNNING || tp->control.in_infcall))
5468 fprintf_unfiltered (gdb_stdlog,
5469 "infrun: restart threads: "
5470 "[%s] not meant to be running\n",
5471 target_pid_to_str (tp->ptid));
5478 fprintf_unfiltered (gdb_stdlog,
5479 "infrun: restart threads: [%s] resumed\n",
5480 target_pid_to_str (tp->ptid));
5481 gdb_assert (tp->executing || tp->suspend.waitstatus_pending_p);
5485 if (thread_is_in_step_over_chain (tp))
5488 fprintf_unfiltered (gdb_stdlog,
5489 "infrun: restart threads: "
5490 "[%s] needs step-over\n",
5491 target_pid_to_str (tp->ptid));
5492 gdb_assert (!tp->resumed);
5497 if (tp->suspend.waitstatus_pending_p)
5500 fprintf_unfiltered (gdb_stdlog,
5501 "infrun: restart threads: "
5502 "[%s] has pending status\n",
5503 target_pid_to_str (tp->ptid));
5508 gdb_assert (!tp->stop_requested);
5510 /* If some thread needs to start a step-over at this point, it
5511 should still be in the step-over queue, and thus skipped
5513 if (thread_still_needs_step_over (tp))
5515 internal_error (__FILE__, __LINE__,
5516 "thread [%s] needs a step-over, but not in "
5517 "step-over queue\n",
5518 target_pid_to_str (tp->ptid));
5521 if (currently_stepping (tp))
5524 fprintf_unfiltered (gdb_stdlog,
5525 "infrun: restart threads: [%s] was stepping\n",
5526 target_pid_to_str (tp->ptid));
5527 keep_going_stepped_thread (tp);
5531 struct execution_control_state ecss;
5532 struct execution_control_state *ecs = &ecss;
5535 fprintf_unfiltered (gdb_stdlog,
5536 "infrun: restart threads: [%s] continuing\n",
5537 target_pid_to_str (tp->ptid));
5538 reset_ecs (ecs, tp);
5539 switch_to_thread (tp->ptid);
5540 keep_going_pass_signal (ecs);
5545 /* Callback for iterate_over_threads. Find a resumed thread that has
5546 a pending waitstatus. */
5549 resumed_thread_with_pending_status (struct thread_info *tp,
5553 && tp->suspend.waitstatus_pending_p);
5556 /* Called when we get an event that may finish an in-line or
5557 out-of-line (displaced stepping) step-over started previously.
5558 Return true if the event is processed and we should go back to the
5559 event loop; false if the caller should continue processing the
5563 finish_step_over (struct execution_control_state *ecs)
5565 int had_step_over_info;
5567 displaced_step_fixup (ecs->ptid,
5568 ecs->event_thread->suspend.stop_signal);
5570 had_step_over_info = step_over_info_valid_p ();
5572 if (had_step_over_info)
5574 /* If we're stepping over a breakpoint with all threads locked,
5575 then only the thread that was stepped should be reporting
5577 gdb_assert (ecs->event_thread->control.trap_expected);
5579 clear_step_over_info ();
5582 if (!target_is_non_stop_p ())
5585 /* Start a new step-over in another thread if there's one that
5589 /* If we were stepping over a breakpoint before, and haven't started
5590 a new in-line step-over sequence, then restart all other threads
5591 (except the event thread). We can't do this in all-stop, as then
5592 e.g., we wouldn't be able to issue any other remote packet until
5593 these other threads stop. */
5594 if (had_step_over_info && !step_over_info_valid_p ())
5596 struct thread_info *pending;
5598 /* If we only have threads with pending statuses, the restart
5599 below won't restart any thread and so nothing re-inserts the
5600 breakpoint we just stepped over. But we need it inserted
5601 when we later process the pending events, otherwise if
5602 another thread has a pending event for this breakpoint too,
5603 we'd discard its event (because the breakpoint that
5604 originally caused the event was no longer inserted). */
5605 context_switch (ecs->ptid);
5606 insert_breakpoints ();
5608 restart_threads (ecs->event_thread);
5610 /* If we have events pending, go through handle_inferior_event
5611 again, picking up a pending event at random. This avoids
5612 thread starvation. */
5614 /* But not if we just stepped over a watchpoint in order to let
5615 the instruction execute so we can evaluate its expression.
5616 The set of watchpoints that triggered is recorded in the
5617 breakpoint objects themselves (see bp->watchpoint_triggered).
5618 If we processed another event first, that other event could
5619 clobber this info. */
5620 if (ecs->event_thread->stepping_over_watchpoint)
5623 pending = iterate_over_threads (resumed_thread_with_pending_status,
5625 if (pending != NULL)
5627 struct thread_info *tp = ecs->event_thread;
5628 struct regcache *regcache;
5632 fprintf_unfiltered (gdb_stdlog,
5633 "infrun: found resumed threads with "
5634 "pending events, saving status\n");
5637 gdb_assert (pending != tp);
5639 /* Record the event thread's event for later. */
5640 save_waitstatus (tp, &ecs->ws);
5641 /* This was cleared early, by handle_inferior_event. Set it
5642 so this pending event is considered by
5646 gdb_assert (!tp->executing);
5648 regcache = get_thread_regcache (tp->ptid);
5649 tp->suspend.stop_pc = regcache_read_pc (regcache);
5653 fprintf_unfiltered (gdb_stdlog,
5654 "infrun: saved stop_pc=%s for %s "
5655 "(currently_stepping=%d)\n",
5656 paddress (target_gdbarch (),
5657 tp->suspend.stop_pc),
5658 target_pid_to_str (tp->ptid),
5659 currently_stepping (tp));
5662 /* This in-line step-over finished; clear this so we won't
5663 start a new one. This is what handle_signal_stop would
5664 do, if we returned false. */
5665 tp->stepping_over_breakpoint = 0;
5667 /* Wake up the event loop again. */
5668 mark_async_event_handler (infrun_async_inferior_event_token);
5670 prepare_to_wait (ecs);
5678 /* Come here when the program has stopped with a signal. */
5681 handle_signal_stop (struct execution_control_state *ecs)
5683 struct frame_info *frame;
5684 struct gdbarch *gdbarch;
5685 int stopped_by_watchpoint;
5686 enum stop_kind stop_soon;
5689 gdb_assert (ecs->ws.kind == TARGET_WAITKIND_STOPPED);
5691 ecs->event_thread->suspend.stop_signal = ecs->ws.value.sig;
5693 /* Do we need to clean up the state of a thread that has
5694 completed a displaced single-step? (Doing so usually affects
5695 the PC, so do it here, before we set stop_pc.) */
5696 if (finish_step_over (ecs))
5699 /* If we either finished a single-step or hit a breakpoint, but
5700 the user wanted this thread to be stopped, pretend we got a
5701 SIG0 (generic unsignaled stop). */
5702 if (ecs->event_thread->stop_requested
5703 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
5704 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5706 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5710 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5711 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5712 struct cleanup *old_chain = save_inferior_ptid ();
5714 inferior_ptid = ecs->ptid;
5716 fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = %s\n",
5717 paddress (gdbarch, stop_pc));
5718 if (target_stopped_by_watchpoint ())
5722 fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n");
5724 if (target_stopped_data_address (¤t_target, &addr))
5725 fprintf_unfiltered (gdb_stdlog,
5726 "infrun: stopped data address = %s\n",
5727 paddress (gdbarch, addr));
5729 fprintf_unfiltered (gdb_stdlog,
5730 "infrun: (no data address available)\n");
5733 do_cleanups (old_chain);
5736 /* This is originated from start_remote(), start_inferior() and
5737 shared libraries hook functions. */
5738 stop_soon = get_inferior_stop_soon (ecs->ptid);
5739 if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE)
5741 if (!ptid_equal (ecs->ptid, inferior_ptid))
5742 context_switch (ecs->ptid);
5744 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
5745 stop_print_frame = 1;
5750 /* This originates from attach_command(). We need to overwrite
5751 the stop_signal here, because some kernels don't ignore a
5752 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5753 See more comments in inferior.h. On the other hand, if we
5754 get a non-SIGSTOP, report it to the user - assume the backend
5755 will handle the SIGSTOP if it should show up later.
5757 Also consider that the attach is complete when we see a
5758 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5759 target extended-remote report it instead of a SIGSTOP
5760 (e.g. gdbserver). We already rely on SIGTRAP being our
5761 signal, so this is no exception.
5763 Also consider that the attach is complete when we see a
5764 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5765 the target to stop all threads of the inferior, in case the
5766 low level attach operation doesn't stop them implicitly. If
5767 they weren't stopped implicitly, then the stub will report a
5768 GDB_SIGNAL_0, meaning: stopped for no particular reason
5769 other than GDB's request. */
5770 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
5771 && (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_STOP
5772 || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5773 || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_0))
5775 stop_print_frame = 1;
5777 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5781 /* See if something interesting happened to the non-current thread. If
5782 so, then switch to that thread. */
5783 if (!ptid_equal (ecs->ptid, inferior_ptid))
5786 fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n");
5788 context_switch (ecs->ptid);
5790 if (deprecated_context_hook)
5791 deprecated_context_hook (ptid_to_global_thread_id (ecs->ptid));
5794 /* At this point, get hold of the now-current thread's frame. */
5795 frame = get_current_frame ();
5796 gdbarch = get_frame_arch (frame);
5798 /* Pull the single step breakpoints out of the target. */
5799 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
5801 struct regcache *regcache;
5802 struct address_space *aspace;
5805 regcache = get_thread_regcache (ecs->ptid);
5806 aspace = get_regcache_aspace (regcache);
5807 pc = regcache_read_pc (regcache);
5809 /* However, before doing so, if this single-step breakpoint was
5810 actually for another thread, set this thread up for moving
5812 if (!thread_has_single_step_breakpoint_here (ecs->event_thread,
5815 if (single_step_breakpoint_inserted_here_p (aspace, pc))
5819 fprintf_unfiltered (gdb_stdlog,
5820 "infrun: [%s] hit another thread's "
5821 "single-step breakpoint\n",
5822 target_pid_to_str (ecs->ptid));
5824 ecs->hit_singlestep_breakpoint = 1;
5831 fprintf_unfiltered (gdb_stdlog,
5832 "infrun: [%s] hit its "
5833 "single-step breakpoint\n",
5834 target_pid_to_str (ecs->ptid));
5838 delete_just_stopped_threads_single_step_breakpoints ();
5840 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5841 && ecs->event_thread->control.trap_expected
5842 && ecs->event_thread->stepping_over_watchpoint)
5843 stopped_by_watchpoint = 0;
5845 stopped_by_watchpoint = watchpoints_triggered (&ecs->ws);
5847 /* If necessary, step over this watchpoint. We'll be back to display
5849 if (stopped_by_watchpoint
5850 && (target_have_steppable_watchpoint
5851 || gdbarch_have_nonsteppable_watchpoint (gdbarch)))
5853 /* At this point, we are stopped at an instruction which has
5854 attempted to write to a piece of memory under control of
5855 a watchpoint. The instruction hasn't actually executed
5856 yet. If we were to evaluate the watchpoint expression
5857 now, we would get the old value, and therefore no change
5858 would seem to have occurred.
5860 In order to make watchpoints work `right', we really need
5861 to complete the memory write, and then evaluate the
5862 watchpoint expression. We do this by single-stepping the
5865 It may not be necessary to disable the watchpoint to step over
5866 it. For example, the PA can (with some kernel cooperation)
5867 single step over a watchpoint without disabling the watchpoint.
5869 It is far more common to need to disable a watchpoint to step
5870 the inferior over it. If we have non-steppable watchpoints,
5871 we must disable the current watchpoint; it's simplest to
5872 disable all watchpoints.
5874 Any breakpoint at PC must also be stepped over -- if there's
5875 one, it will have already triggered before the watchpoint
5876 triggered, and we either already reported it to the user, or
5877 it didn't cause a stop and we called keep_going. In either
5878 case, if there was a breakpoint at PC, we must be trying to
5880 ecs->event_thread->stepping_over_watchpoint = 1;
5885 ecs->event_thread->stepping_over_breakpoint = 0;
5886 ecs->event_thread->stepping_over_watchpoint = 0;
5887 bpstat_clear (&ecs->event_thread->control.stop_bpstat);
5888 ecs->event_thread->control.stop_step = 0;
5889 stop_print_frame = 1;
5890 stopped_by_random_signal = 0;
5892 /* Hide inlined functions starting here, unless we just performed stepi or
5893 nexti. After stepi and nexti, always show the innermost frame (not any
5894 inline function call sites). */
5895 if (ecs->event_thread->control.step_range_end != 1)
5897 struct address_space *aspace =
5898 get_regcache_aspace (get_thread_regcache (ecs->ptid));
5900 /* skip_inline_frames is expensive, so we avoid it if we can
5901 determine that the address is one where functions cannot have
5902 been inlined. This improves performance with inferiors that
5903 load a lot of shared libraries, because the solib event
5904 breakpoint is defined as the address of a function (i.e. not
5905 inline). Note that we have to check the previous PC as well
5906 as the current one to catch cases when we have just
5907 single-stepped off a breakpoint prior to reinstating it.
5908 Note that we're assuming that the code we single-step to is
5909 not inline, but that's not definitive: there's nothing
5910 preventing the event breakpoint function from containing
5911 inlined code, and the single-step ending up there. If the
5912 user had set a breakpoint on that inlined code, the missing
5913 skip_inline_frames call would break things. Fortunately
5914 that's an extremely unlikely scenario. */
5915 if (!pc_at_non_inline_function (aspace, stop_pc, &ecs->ws)
5916 && !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5917 && ecs->event_thread->control.trap_expected
5918 && pc_at_non_inline_function (aspace,
5919 ecs->event_thread->prev_pc,
5922 skip_inline_frames (ecs->ptid);
5924 /* Re-fetch current thread's frame in case that invalidated
5926 frame = get_current_frame ();
5927 gdbarch = get_frame_arch (frame);
5931 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5932 && ecs->event_thread->control.trap_expected
5933 && gdbarch_single_step_through_delay_p (gdbarch)
5934 && currently_stepping (ecs->event_thread))
5936 /* We're trying to step off a breakpoint. Turns out that we're
5937 also on an instruction that needs to be stepped multiple
5938 times before it's been fully executing. E.g., architectures
5939 with a delay slot. It needs to be stepped twice, once for
5940 the instruction and once for the delay slot. */
5941 int step_through_delay
5942 = gdbarch_single_step_through_delay (gdbarch, frame);
5944 if (debug_infrun && step_through_delay)
5945 fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n");
5946 if (ecs->event_thread->control.step_range_end == 0
5947 && step_through_delay)
5949 /* The user issued a continue when stopped at a breakpoint.
5950 Set up for another trap and get out of here. */
5951 ecs->event_thread->stepping_over_breakpoint = 1;
5955 else if (step_through_delay)
5957 /* The user issued a step when stopped at a breakpoint.
5958 Maybe we should stop, maybe we should not - the delay
5959 slot *might* correspond to a line of source. In any
5960 case, don't decide that here, just set
5961 ecs->stepping_over_breakpoint, making sure we
5962 single-step again before breakpoints are re-inserted. */
5963 ecs->event_thread->stepping_over_breakpoint = 1;
5967 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5968 handles this event. */
5969 ecs->event_thread->control.stop_bpstat
5970 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5971 stop_pc, ecs->ptid, &ecs->ws);
5973 /* Following in case break condition called a
5975 stop_print_frame = 1;
5977 /* This is where we handle "moribund" watchpoints. Unlike
5978 software breakpoints traps, hardware watchpoint traps are
5979 always distinguishable from random traps. If no high-level
5980 watchpoint is associated with the reported stop data address
5981 anymore, then the bpstat does not explain the signal ---
5982 simply make sure to ignore it if `stopped_by_watchpoint' is
5986 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5987 && !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
5989 && stopped_by_watchpoint)
5990 fprintf_unfiltered (gdb_stdlog,
5991 "infrun: no user watchpoint explains "
5992 "watchpoint SIGTRAP, ignoring\n");
5994 /* NOTE: cagney/2003-03-29: These checks for a random signal
5995 at one stage in the past included checks for an inferior
5996 function call's call dummy's return breakpoint. The original
5997 comment, that went with the test, read:
5999 ``End of a stack dummy. Some systems (e.g. Sony news) give
6000 another signal besides SIGTRAP, so check here as well as
6003 If someone ever tries to get call dummys on a
6004 non-executable stack to work (where the target would stop
6005 with something like a SIGSEGV), then those tests might need
6006 to be re-instated. Given, however, that the tests were only
6007 enabled when momentary breakpoints were not being used, I
6008 suspect that it won't be the case.
6010 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
6011 be necessary for call dummies on a non-executable stack on
6014 /* See if the breakpoints module can explain the signal. */
6016 = !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
6017 ecs->event_thread->suspend.stop_signal);
6019 /* Maybe this was a trap for a software breakpoint that has since
6021 if (random_signal && target_stopped_by_sw_breakpoint ())
6023 if (program_breakpoint_here_p (gdbarch, stop_pc))
6025 struct regcache *regcache;
6028 /* Re-adjust PC to what the program would see if GDB was not
6030 regcache = get_thread_regcache (ecs->event_thread->ptid);
6031 decr_pc = gdbarch_decr_pc_after_break (gdbarch);
6034 struct cleanup *old_cleanups = make_cleanup (null_cleanup, NULL);
6036 if (record_full_is_used ())
6037 record_full_gdb_operation_disable_set ();
6039 regcache_write_pc (regcache, stop_pc + decr_pc);
6041 do_cleanups (old_cleanups);
6046 /* A delayed software breakpoint event. Ignore the trap. */
6048 fprintf_unfiltered (gdb_stdlog,
6049 "infrun: delayed software breakpoint "
6050 "trap, ignoring\n");
6055 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6056 has since been removed. */
6057 if (random_signal && target_stopped_by_hw_breakpoint ())
6059 /* A delayed hardware breakpoint event. Ignore the trap. */
6061 fprintf_unfiltered (gdb_stdlog,
6062 "infrun: delayed hardware breakpoint/watchpoint "
6063 "trap, ignoring\n");
6067 /* If not, perhaps stepping/nexting can. */
6069 random_signal = !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
6070 && currently_stepping (ecs->event_thread));
6072 /* Perhaps the thread hit a single-step breakpoint of _another_
6073 thread. Single-step breakpoints are transparent to the
6074 breakpoints module. */
6076 random_signal = !ecs->hit_singlestep_breakpoint;
6078 /* No? Perhaps we got a moribund watchpoint. */
6080 random_signal = !stopped_by_watchpoint;
6082 /* Always stop if the user explicitly requested this thread to
6084 if (ecs->event_thread->stop_requested)
6088 fprintf_unfiltered (gdb_stdlog, "infrun: user-requested stop\n");
6091 /* For the program's own signals, act according to
6092 the signal handling tables. */
6096 /* Signal not for debugging purposes. */
6097 struct inferior *inf = find_inferior_ptid (ecs->ptid);
6098 enum gdb_signal stop_signal = ecs->event_thread->suspend.stop_signal;
6101 fprintf_unfiltered (gdb_stdlog, "infrun: random signal (%s)\n",
6102 gdb_signal_to_symbol_string (stop_signal));
6104 stopped_by_random_signal = 1;
6106 /* Always stop on signals if we're either just gaining control
6107 of the program, or the user explicitly requested this thread
6108 to remain stopped. */
6109 if (stop_soon != NO_STOP_QUIETLY
6110 || ecs->event_thread->stop_requested
6112 && signal_stop_state (ecs->event_thread->suspend.stop_signal)))
6118 /* Notify observers the signal has "handle print" set. Note we
6119 returned early above if stopping; normal_stop handles the
6120 printing in that case. */
6121 if (signal_print[ecs->event_thread->suspend.stop_signal])
6123 /* The signal table tells us to print about this signal. */
6124 target_terminal_ours_for_output ();
6125 observer_notify_signal_received (ecs->event_thread->suspend.stop_signal);
6126 target_terminal_inferior ();
6129 /* Clear the signal if it should not be passed. */
6130 if (signal_program[ecs->event_thread->suspend.stop_signal] == 0)
6131 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
6133 if (ecs->event_thread->prev_pc == stop_pc
6134 && ecs->event_thread->control.trap_expected
6135 && ecs->event_thread->control.step_resume_breakpoint == NULL)
6137 /* We were just starting a new sequence, attempting to
6138 single-step off of a breakpoint and expecting a SIGTRAP.
6139 Instead this signal arrives. This signal will take us out
6140 of the stepping range so GDB needs to remember to, when
6141 the signal handler returns, resume stepping off that
6143 /* To simplify things, "continue" is forced to use the same
6144 code paths as single-step - set a breakpoint at the
6145 signal return address and then, once hit, step off that
6148 fprintf_unfiltered (gdb_stdlog,
6149 "infrun: signal arrived while stepping over "
6152 insert_hp_step_resume_breakpoint_at_frame (frame);
6153 ecs->event_thread->step_after_step_resume_breakpoint = 1;
6154 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6155 ecs->event_thread->control.trap_expected = 0;
6157 /* If we were nexting/stepping some other thread, switch to
6158 it, so that we don't continue it, losing control. */
6159 if (!switch_back_to_stepped_thread (ecs))
6164 if (ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_0
6165 && (pc_in_thread_step_range (stop_pc, ecs->event_thread)
6166 || ecs->event_thread->control.step_range_end == 1)
6167 && frame_id_eq (get_stack_frame_id (frame),
6168 ecs->event_thread->control.step_stack_frame_id)
6169 && ecs->event_thread->control.step_resume_breakpoint == NULL)
6171 /* The inferior is about to take a signal that will take it
6172 out of the single step range. Set a breakpoint at the
6173 current PC (which is presumably where the signal handler
6174 will eventually return) and then allow the inferior to
6177 Note that this is only needed for a signal delivered
6178 while in the single-step range. Nested signals aren't a
6179 problem as they eventually all return. */
6181 fprintf_unfiltered (gdb_stdlog,
6182 "infrun: signal may take us out of "
6183 "single-step range\n");
6185 clear_step_over_info ();
6186 insert_hp_step_resume_breakpoint_at_frame (frame);
6187 ecs->event_thread->step_after_step_resume_breakpoint = 1;
6188 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6189 ecs->event_thread->control.trap_expected = 0;
6194 /* Note: step_resume_breakpoint may be non-NULL. This occures
6195 when either there's a nested signal, or when there's a
6196 pending signal enabled just as the signal handler returns
6197 (leaving the inferior at the step-resume-breakpoint without
6198 actually executing it). Either way continue until the
6199 breakpoint is really hit. */
6201 if (!switch_back_to_stepped_thread (ecs))
6204 fprintf_unfiltered (gdb_stdlog,
6205 "infrun: random signal, keep going\n");
6212 process_event_stop_test (ecs);
6215 /* Come here when we've got some debug event / signal we can explain
6216 (IOW, not a random signal), and test whether it should cause a
6217 stop, or whether we should resume the inferior (transparently).
6218 E.g., could be a breakpoint whose condition evaluates false; we
6219 could be still stepping within the line; etc. */
6222 process_event_stop_test (struct execution_control_state *ecs)
6224 struct symtab_and_line stop_pc_sal;
6225 struct frame_info *frame;
6226 struct gdbarch *gdbarch;
6227 CORE_ADDR jmp_buf_pc;
6228 struct bpstat_what what;
6230 /* Handle cases caused by hitting a breakpoint. */
6232 frame = get_current_frame ();
6233 gdbarch = get_frame_arch (frame);
6235 what = bpstat_what (ecs->event_thread->control.stop_bpstat);
6237 if (what.call_dummy)
6239 stop_stack_dummy = what.call_dummy;
6242 /* A few breakpoint types have callbacks associated (e.g.,
6243 bp_jit_event). Run them now. */
6244 bpstat_run_callbacks (ecs->event_thread->control.stop_bpstat);
6246 /* If we hit an internal event that triggers symbol changes, the
6247 current frame will be invalidated within bpstat_what (e.g., if we
6248 hit an internal solib event). Re-fetch it. */
6249 frame = get_current_frame ();
6250 gdbarch = get_frame_arch (frame);
6252 switch (what.main_action)
6254 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
6255 /* If we hit the breakpoint at longjmp while stepping, we
6256 install a momentary breakpoint at the target of the
6260 fprintf_unfiltered (gdb_stdlog,
6261 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6263 ecs->event_thread->stepping_over_breakpoint = 1;
6265 if (what.is_longjmp)
6267 struct value *arg_value;
6269 /* If we set the longjmp breakpoint via a SystemTap probe,
6270 then use it to extract the arguments. The destination PC
6271 is the third argument to the probe. */
6272 arg_value = probe_safe_evaluate_at_pc (frame, 2);
6275 jmp_buf_pc = value_as_address (arg_value);
6276 jmp_buf_pc = gdbarch_addr_bits_remove (gdbarch, jmp_buf_pc);
6278 else if (!gdbarch_get_longjmp_target_p (gdbarch)
6279 || !gdbarch_get_longjmp_target (gdbarch,
6280 frame, &jmp_buf_pc))
6283 fprintf_unfiltered (gdb_stdlog,
6284 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6285 "(!gdbarch_get_longjmp_target)\n");
6290 /* Insert a breakpoint at resume address. */
6291 insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc);
6294 check_exception_resume (ecs, frame);
6298 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
6300 struct frame_info *init_frame;
6302 /* There are several cases to consider.
6304 1. The initiating frame no longer exists. In this case we
6305 must stop, because the exception or longjmp has gone too
6308 2. The initiating frame exists, and is the same as the
6309 current frame. We stop, because the exception or longjmp
6312 3. The initiating frame exists and is different from the
6313 current frame. This means the exception or longjmp has
6314 been caught beneath the initiating frame, so keep going.
6316 4. longjmp breakpoint has been placed just to protect
6317 against stale dummy frames and user is not interested in
6318 stopping around longjmps. */
6321 fprintf_unfiltered (gdb_stdlog,
6322 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6324 gdb_assert (ecs->event_thread->control.exception_resume_breakpoint
6326 delete_exception_resume_breakpoint (ecs->event_thread);
6328 if (what.is_longjmp)
6330 check_longjmp_breakpoint_for_call_dummy (ecs->event_thread);
6332 if (!frame_id_p (ecs->event_thread->initiating_frame))
6340 init_frame = frame_find_by_id (ecs->event_thread->initiating_frame);
6344 struct frame_id current_id
6345 = get_frame_id (get_current_frame ());
6346 if (frame_id_eq (current_id,
6347 ecs->event_thread->initiating_frame))
6349 /* Case 2. Fall through. */
6359 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6361 delete_step_resume_breakpoint (ecs->event_thread);
6363 end_stepping_range (ecs);
6367 case BPSTAT_WHAT_SINGLE:
6369 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
6370 ecs->event_thread->stepping_over_breakpoint = 1;
6371 /* Still need to check other stuff, at least the case where we
6372 are stepping and step out of the right range. */
6375 case BPSTAT_WHAT_STEP_RESUME:
6377 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6379 delete_step_resume_breakpoint (ecs->event_thread);
6380 if (ecs->event_thread->control.proceed_to_finish
6381 && execution_direction == EXEC_REVERSE)
6383 struct thread_info *tp = ecs->event_thread;
6385 /* We are finishing a function in reverse, and just hit the
6386 step-resume breakpoint at the start address of the
6387 function, and we're almost there -- just need to back up
6388 by one more single-step, which should take us back to the
6390 tp->control.step_range_start = tp->control.step_range_end = 1;
6394 fill_in_stop_func (gdbarch, ecs);
6395 if (stop_pc == ecs->stop_func_start
6396 && execution_direction == EXEC_REVERSE)
6398 /* We are stepping over a function call in reverse, and just
6399 hit the step-resume breakpoint at the start address of
6400 the function. Go back to single-stepping, which should
6401 take us back to the function call. */
6402 ecs->event_thread->stepping_over_breakpoint = 1;
6408 case BPSTAT_WHAT_STOP_NOISY:
6410 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6411 stop_print_frame = 1;
6413 /* Assume the thread stopped for a breapoint. We'll still check
6414 whether a/the breakpoint is there when the thread is next
6416 ecs->event_thread->stepping_over_breakpoint = 1;
6421 case BPSTAT_WHAT_STOP_SILENT:
6423 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6424 stop_print_frame = 0;
6426 /* Assume the thread stopped for a breapoint. We'll still check
6427 whether a/the breakpoint is there when the thread is next
6429 ecs->event_thread->stepping_over_breakpoint = 1;
6433 case BPSTAT_WHAT_HP_STEP_RESUME:
6435 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6437 delete_step_resume_breakpoint (ecs->event_thread);
6438 if (ecs->event_thread->step_after_step_resume_breakpoint)
6440 /* Back when the step-resume breakpoint was inserted, we
6441 were trying to single-step off a breakpoint. Go back to
6443 ecs->event_thread->step_after_step_resume_breakpoint = 0;
6444 ecs->event_thread->stepping_over_breakpoint = 1;
6450 case BPSTAT_WHAT_KEEP_CHECKING:
6454 /* If we stepped a permanent breakpoint and we had a high priority
6455 step-resume breakpoint for the address we stepped, but we didn't
6456 hit it, then we must have stepped into the signal handler. The
6457 step-resume was only necessary to catch the case of _not_
6458 stepping into the handler, so delete it, and fall through to
6459 checking whether the step finished. */
6460 if (ecs->event_thread->stepped_breakpoint)
6462 struct breakpoint *sr_bp
6463 = ecs->event_thread->control.step_resume_breakpoint;
6466 && sr_bp->loc->permanent
6467 && sr_bp->type == bp_hp_step_resume
6468 && sr_bp->loc->address == ecs->event_thread->prev_pc)
6471 fprintf_unfiltered (gdb_stdlog,
6472 "infrun: stepped permanent breakpoint, stopped in "
6474 delete_step_resume_breakpoint (ecs->event_thread);
6475 ecs->event_thread->step_after_step_resume_breakpoint = 0;
6479 /* We come here if we hit a breakpoint but should not stop for it.
6480 Possibly we also were stepping and should stop for that. So fall
6481 through and test for stepping. But, if not stepping, do not
6484 /* In all-stop mode, if we're currently stepping but have stopped in
6485 some other thread, we need to switch back to the stepped thread. */
6486 if (switch_back_to_stepped_thread (ecs))
6489 if (ecs->event_thread->control.step_resume_breakpoint)
6492 fprintf_unfiltered (gdb_stdlog,
6493 "infrun: step-resume breakpoint is inserted\n");
6495 /* Having a step-resume breakpoint overrides anything
6496 else having to do with stepping commands until
6497 that breakpoint is reached. */
6502 if (ecs->event_thread->control.step_range_end == 0)
6505 fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n");
6506 /* Likewise if we aren't even stepping. */
6511 /* Re-fetch current thread's frame in case the code above caused
6512 the frame cache to be re-initialized, making our FRAME variable
6513 a dangling pointer. */
6514 frame = get_current_frame ();
6515 gdbarch = get_frame_arch (frame);
6516 fill_in_stop_func (gdbarch, ecs);
6518 /* If stepping through a line, keep going if still within it.
6520 Note that step_range_end is the address of the first instruction
6521 beyond the step range, and NOT the address of the last instruction
6524 Note also that during reverse execution, we may be stepping
6525 through a function epilogue and therefore must detect when
6526 the current-frame changes in the middle of a line. */
6528 if (pc_in_thread_step_range (stop_pc, ecs->event_thread)
6529 && (execution_direction != EXEC_REVERSE
6530 || frame_id_eq (get_frame_id (frame),
6531 ecs->event_thread->control.step_frame_id)))
6535 (gdb_stdlog, "infrun: stepping inside range [%s-%s]\n",
6536 paddress (gdbarch, ecs->event_thread->control.step_range_start),
6537 paddress (gdbarch, ecs->event_thread->control.step_range_end));
6539 /* Tentatively re-enable range stepping; `resume' disables it if
6540 necessary (e.g., if we're stepping over a breakpoint or we
6541 have software watchpoints). */
6542 ecs->event_thread->control.may_range_step = 1;
6544 /* When stepping backward, stop at beginning of line range
6545 (unless it's the function entry point, in which case
6546 keep going back to the call point). */
6547 if (stop_pc == ecs->event_thread->control.step_range_start
6548 && stop_pc != ecs->stop_func_start
6549 && execution_direction == EXEC_REVERSE)
6550 end_stepping_range (ecs);
6557 /* We stepped out of the stepping range. */
6559 /* If we are stepping at the source level and entered the runtime
6560 loader dynamic symbol resolution code...
6562 EXEC_FORWARD: we keep on single stepping until we exit the run
6563 time loader code and reach the callee's address.
6565 EXEC_REVERSE: we've already executed the callee (backward), and
6566 the runtime loader code is handled just like any other
6567 undebuggable function call. Now we need only keep stepping
6568 backward through the trampoline code, and that's handled further
6569 down, so there is nothing for us to do here. */
6571 if (execution_direction != EXEC_REVERSE
6572 && ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6573 && in_solib_dynsym_resolve_code (stop_pc))
6575 CORE_ADDR pc_after_resolver =
6576 gdbarch_skip_solib_resolver (gdbarch, stop_pc);
6579 fprintf_unfiltered (gdb_stdlog,
6580 "infrun: stepped into dynsym resolve code\n");
6582 if (pc_after_resolver)
6584 /* Set up a step-resume breakpoint at the address
6585 indicated by SKIP_SOLIB_RESOLVER. */
6586 struct symtab_and_line sr_sal;
6589 sr_sal.pc = pc_after_resolver;
6590 sr_sal.pspace = get_frame_program_space (frame);
6592 insert_step_resume_breakpoint_at_sal (gdbarch,
6593 sr_sal, null_frame_id);
6600 if (ecs->event_thread->control.step_range_end != 1
6601 && (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6602 || ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
6603 && get_frame_type (frame) == SIGTRAMP_FRAME)
6606 fprintf_unfiltered (gdb_stdlog,
6607 "infrun: stepped into signal trampoline\n");
6608 /* The inferior, while doing a "step" or "next", has ended up in
6609 a signal trampoline (either by a signal being delivered or by
6610 the signal handler returning). Just single-step until the
6611 inferior leaves the trampoline (either by calling the handler
6617 /* If we're in the return path from a shared library trampoline,
6618 we want to proceed through the trampoline when stepping. */
6619 /* macro/2012-04-25: This needs to come before the subroutine
6620 call check below as on some targets return trampolines look
6621 like subroutine calls (MIPS16 return thunks). */
6622 if (gdbarch_in_solib_return_trampoline (gdbarch,
6623 stop_pc, ecs->stop_func_name)
6624 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
6626 /* Determine where this trampoline returns. */
6627 CORE_ADDR real_stop_pc;
6629 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
6632 fprintf_unfiltered (gdb_stdlog,
6633 "infrun: stepped into solib return tramp\n");
6635 /* Only proceed through if we know where it's going. */
6638 /* And put the step-breakpoint there and go until there. */
6639 struct symtab_and_line sr_sal;
6641 init_sal (&sr_sal); /* initialize to zeroes */
6642 sr_sal.pc = real_stop_pc;
6643 sr_sal.section = find_pc_overlay (sr_sal.pc);
6644 sr_sal.pspace = get_frame_program_space (frame);
6646 /* Do not specify what the fp should be when we stop since
6647 on some machines the prologue is where the new fp value
6649 insert_step_resume_breakpoint_at_sal (gdbarch,
6650 sr_sal, null_frame_id);
6652 /* Restart without fiddling with the step ranges or
6659 /* Check for subroutine calls. The check for the current frame
6660 equalling the step ID is not necessary - the check of the
6661 previous frame's ID is sufficient - but it is a common case and
6662 cheaper than checking the previous frame's ID.
6664 NOTE: frame_id_eq will never report two invalid frame IDs as
6665 being equal, so to get into this block, both the current and
6666 previous frame must have valid frame IDs. */
6667 /* The outer_frame_id check is a heuristic to detect stepping
6668 through startup code. If we step over an instruction which
6669 sets the stack pointer from an invalid value to a valid value,
6670 we may detect that as a subroutine call from the mythical
6671 "outermost" function. This could be fixed by marking
6672 outermost frames as !stack_p,code_p,special_p. Then the
6673 initial outermost frame, before sp was valid, would
6674 have code_addr == &_start. See the comment in frame_id_eq
6676 if (!frame_id_eq (get_stack_frame_id (frame),
6677 ecs->event_thread->control.step_stack_frame_id)
6678 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6679 ecs->event_thread->control.step_stack_frame_id)
6680 && (!frame_id_eq (ecs->event_thread->control.step_stack_frame_id,
6682 || (ecs->event_thread->control.step_start_function
6683 != find_pc_function (stop_pc)))))
6685 CORE_ADDR real_stop_pc;
6688 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n");
6690 if (ecs->event_thread->control.step_over_calls == STEP_OVER_NONE)
6692 /* I presume that step_over_calls is only 0 when we're
6693 supposed to be stepping at the assembly language level
6694 ("stepi"). Just stop. */
6695 /* And this works the same backward as frontward. MVS */
6696 end_stepping_range (ecs);
6700 /* Reverse stepping through solib trampolines. */
6702 if (execution_direction == EXEC_REVERSE
6703 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE
6704 && (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
6705 || (ecs->stop_func_start == 0
6706 && in_solib_dynsym_resolve_code (stop_pc))))
6708 /* Any solib trampoline code can be handled in reverse
6709 by simply continuing to single-step. We have already
6710 executed the solib function (backwards), and a few
6711 steps will take us back through the trampoline to the
6717 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
6719 /* We're doing a "next".
6721 Normal (forward) execution: set a breakpoint at the
6722 callee's return address (the address at which the caller
6725 Reverse (backward) execution. set the step-resume
6726 breakpoint at the start of the function that we just
6727 stepped into (backwards), and continue to there. When we
6728 get there, we'll need to single-step back to the caller. */
6730 if (execution_direction == EXEC_REVERSE)
6732 /* If we're already at the start of the function, we've either
6733 just stepped backward into a single instruction function,
6734 or stepped back out of a signal handler to the first instruction
6735 of the function. Just keep going, which will single-step back
6737 if (ecs->stop_func_start != stop_pc && ecs->stop_func_start != 0)
6739 struct symtab_and_line sr_sal;
6741 /* Normal function call return (static or dynamic). */
6743 sr_sal.pc = ecs->stop_func_start;
6744 sr_sal.pspace = get_frame_program_space (frame);
6745 insert_step_resume_breakpoint_at_sal (gdbarch,
6746 sr_sal, null_frame_id);
6750 insert_step_resume_breakpoint_at_caller (frame);
6756 /* If we are in a function call trampoline (a stub between the
6757 calling routine and the real function), locate the real
6758 function. That's what tells us (a) whether we want to step
6759 into it at all, and (b) what prologue we want to run to the
6760 end of, if we do step into it. */
6761 real_stop_pc = skip_language_trampoline (frame, stop_pc);
6762 if (real_stop_pc == 0)
6763 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
6764 if (real_stop_pc != 0)
6765 ecs->stop_func_start = real_stop_pc;
6767 if (real_stop_pc != 0 && in_solib_dynsym_resolve_code (real_stop_pc))
6769 struct symtab_and_line sr_sal;
6772 sr_sal.pc = ecs->stop_func_start;
6773 sr_sal.pspace = get_frame_program_space (frame);
6775 insert_step_resume_breakpoint_at_sal (gdbarch,
6776 sr_sal, null_frame_id);
6781 /* If we have line number information for the function we are
6782 thinking of stepping into and the function isn't on the skip
6785 If there are several symtabs at that PC (e.g. with include
6786 files), just want to know whether *any* of them have line
6787 numbers. find_pc_line handles this. */
6789 struct symtab_and_line tmp_sal;
6791 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
6792 if (tmp_sal.line != 0
6793 && !function_name_is_marked_for_skip (ecs->stop_func_name,
6796 if (execution_direction == EXEC_REVERSE)
6797 handle_step_into_function_backward (gdbarch, ecs);
6799 handle_step_into_function (gdbarch, ecs);
6804 /* If we have no line number and the step-stop-if-no-debug is
6805 set, we stop the step so that the user has a chance to switch
6806 in assembly mode. */
6807 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6808 && step_stop_if_no_debug)
6810 end_stepping_range (ecs);
6814 if (execution_direction == EXEC_REVERSE)
6816 /* If we're already at the start of the function, we've either just
6817 stepped backward into a single instruction function without line
6818 number info, or stepped back out of a signal handler to the first
6819 instruction of the function without line number info. Just keep
6820 going, which will single-step back to the caller. */
6821 if (ecs->stop_func_start != stop_pc)
6823 /* Set a breakpoint at callee's start address.
6824 From there we can step once and be back in the caller. */
6825 struct symtab_and_line sr_sal;
6828 sr_sal.pc = ecs->stop_func_start;
6829 sr_sal.pspace = get_frame_program_space (frame);
6830 insert_step_resume_breakpoint_at_sal (gdbarch,
6831 sr_sal, null_frame_id);
6835 /* Set a breakpoint at callee's return address (the address
6836 at which the caller will resume). */
6837 insert_step_resume_breakpoint_at_caller (frame);
6843 /* Reverse stepping through solib trampolines. */
6845 if (execution_direction == EXEC_REVERSE
6846 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
6848 if (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
6849 || (ecs->stop_func_start == 0
6850 && in_solib_dynsym_resolve_code (stop_pc)))
6852 /* Any solib trampoline code can be handled in reverse
6853 by simply continuing to single-step. We have already
6854 executed the solib function (backwards), and a few
6855 steps will take us back through the trampoline to the
6860 else if (in_solib_dynsym_resolve_code (stop_pc))
6862 /* Stepped backward into the solib dynsym resolver.
6863 Set a breakpoint at its start and continue, then
6864 one more step will take us out. */
6865 struct symtab_and_line sr_sal;
6868 sr_sal.pc = ecs->stop_func_start;
6869 sr_sal.pspace = get_frame_program_space (frame);
6870 insert_step_resume_breakpoint_at_sal (gdbarch,
6871 sr_sal, null_frame_id);
6877 stop_pc_sal = find_pc_line (stop_pc, 0);
6879 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6880 the trampoline processing logic, however, there are some trampolines
6881 that have no names, so we should do trampoline handling first. */
6882 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6883 && ecs->stop_func_name == NULL
6884 && stop_pc_sal.line == 0)
6887 fprintf_unfiltered (gdb_stdlog,
6888 "infrun: stepped into undebuggable function\n");
6890 /* The inferior just stepped into, or returned to, an
6891 undebuggable function (where there is no debugging information
6892 and no line number corresponding to the address where the
6893 inferior stopped). Since we want to skip this kind of code,
6894 we keep going until the inferior returns from this
6895 function - unless the user has asked us not to (via
6896 set step-mode) or we no longer know how to get back
6897 to the call site. */
6898 if (step_stop_if_no_debug
6899 || !frame_id_p (frame_unwind_caller_id (frame)))
6901 /* If we have no line number and the step-stop-if-no-debug
6902 is set, we stop the step so that the user has a chance to
6903 switch in assembly mode. */
6904 end_stepping_range (ecs);
6909 /* Set a breakpoint at callee's return address (the address
6910 at which the caller will resume). */
6911 insert_step_resume_breakpoint_at_caller (frame);
6917 if (ecs->event_thread->control.step_range_end == 1)
6919 /* It is stepi or nexti. We always want to stop stepping after
6922 fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
6923 end_stepping_range (ecs);
6927 if (stop_pc_sal.line == 0)
6929 /* We have no line number information. That means to stop
6930 stepping (does this always happen right after one instruction,
6931 when we do "s" in a function with no line numbers,
6932 or can this happen as a result of a return or longjmp?). */
6934 fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n");
6935 end_stepping_range (ecs);
6939 /* Look for "calls" to inlined functions, part one. If the inline
6940 frame machinery detected some skipped call sites, we have entered
6941 a new inline function. */
6943 if (frame_id_eq (get_frame_id (get_current_frame ()),
6944 ecs->event_thread->control.step_frame_id)
6945 && inline_skipped_frames (ecs->ptid))
6947 struct symtab_and_line call_sal;
6950 fprintf_unfiltered (gdb_stdlog,
6951 "infrun: stepped into inlined function\n");
6953 find_frame_sal (get_current_frame (), &call_sal);
6955 if (ecs->event_thread->control.step_over_calls != STEP_OVER_ALL)
6957 /* For "step", we're going to stop. But if the call site
6958 for this inlined function is on the same source line as
6959 we were previously stepping, go down into the function
6960 first. Otherwise stop at the call site. */
6962 if (call_sal.line == ecs->event_thread->current_line
6963 && call_sal.symtab == ecs->event_thread->current_symtab)
6964 step_into_inline_frame (ecs->ptid);
6966 end_stepping_range (ecs);
6971 /* For "next", we should stop at the call site if it is on a
6972 different source line. Otherwise continue through the
6973 inlined function. */
6974 if (call_sal.line == ecs->event_thread->current_line
6975 && call_sal.symtab == ecs->event_thread->current_symtab)
6978 end_stepping_range (ecs);
6983 /* Look for "calls" to inlined functions, part two. If we are still
6984 in the same real function we were stepping through, but we have
6985 to go further up to find the exact frame ID, we are stepping
6986 through a more inlined call beyond its call site. */
6988 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6989 && !frame_id_eq (get_frame_id (get_current_frame ()),
6990 ecs->event_thread->control.step_frame_id)
6991 && stepped_in_from (get_current_frame (),
6992 ecs->event_thread->control.step_frame_id))
6995 fprintf_unfiltered (gdb_stdlog,
6996 "infrun: stepping through inlined function\n");
6998 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
7001 end_stepping_range (ecs);
7005 if ((stop_pc == stop_pc_sal.pc)
7006 && (ecs->event_thread->current_line != stop_pc_sal.line
7007 || ecs->event_thread->current_symtab != stop_pc_sal.symtab))
7009 /* We are at the start of a different line. So stop. Note that
7010 we don't stop if we step into the middle of a different line.
7011 That is said to make things like for (;;) statements work
7014 fprintf_unfiltered (gdb_stdlog,
7015 "infrun: stepped to a different line\n");
7016 end_stepping_range (ecs);
7020 /* We aren't done stepping.
7022 Optimize by setting the stepping range to the line.
7023 (We might not be in the original line, but if we entered a
7024 new line in mid-statement, we continue stepping. This makes
7025 things like for(;;) statements work better.) */
7027 ecs->event_thread->control.step_range_start = stop_pc_sal.pc;
7028 ecs->event_thread->control.step_range_end = stop_pc_sal.end;
7029 ecs->event_thread->control.may_range_step = 1;
7030 set_step_info (frame, stop_pc_sal);
7033 fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n");
7037 /* In all-stop mode, if we're currently stepping but have stopped in
7038 some other thread, we may need to switch back to the stepped
7039 thread. Returns true we set the inferior running, false if we left
7040 it stopped (and the event needs further processing). */
7043 switch_back_to_stepped_thread (struct execution_control_state *ecs)
7045 if (!target_is_non_stop_p ())
7047 struct thread_info *tp;
7048 struct thread_info *stepping_thread;
7050 /* If any thread is blocked on some internal breakpoint, and we
7051 simply need to step over that breakpoint to get it going
7052 again, do that first. */
7054 /* However, if we see an event for the stepping thread, then we
7055 know all other threads have been moved past their breakpoints
7056 already. Let the caller check whether the step is finished,
7057 etc., before deciding to move it past a breakpoint. */
7058 if (ecs->event_thread->control.step_range_end != 0)
7061 /* Check if the current thread is blocked on an incomplete
7062 step-over, interrupted by a random signal. */
7063 if (ecs->event_thread->control.trap_expected
7064 && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_TRAP)
7068 fprintf_unfiltered (gdb_stdlog,
7069 "infrun: need to finish step-over of [%s]\n",
7070 target_pid_to_str (ecs->event_thread->ptid));
7076 /* Check if the current thread is blocked by a single-step
7077 breakpoint of another thread. */
7078 if (ecs->hit_singlestep_breakpoint)
7082 fprintf_unfiltered (gdb_stdlog,
7083 "infrun: need to step [%s] over single-step "
7085 target_pid_to_str (ecs->ptid));
7091 /* If this thread needs yet another step-over (e.g., stepping
7092 through a delay slot), do it first before moving on to
7094 if (thread_still_needs_step_over (ecs->event_thread))
7098 fprintf_unfiltered (gdb_stdlog,
7099 "infrun: thread [%s] still needs step-over\n",
7100 target_pid_to_str (ecs->event_thread->ptid));
7106 /* If scheduler locking applies even if not stepping, there's no
7107 need to walk over threads. Above we've checked whether the
7108 current thread is stepping. If some other thread not the
7109 event thread is stepping, then it must be that scheduler
7110 locking is not in effect. */
7111 if (schedlock_applies (ecs->event_thread))
7114 /* Otherwise, we no longer expect a trap in the current thread.
7115 Clear the trap_expected flag before switching back -- this is
7116 what keep_going does as well, if we call it. */
7117 ecs->event_thread->control.trap_expected = 0;
7119 /* Likewise, clear the signal if it should not be passed. */
7120 if (!signal_program[ecs->event_thread->suspend.stop_signal])
7121 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
7123 /* Do all pending step-overs before actually proceeding with
7125 if (start_step_over ())
7127 prepare_to_wait (ecs);
7131 /* Look for the stepping/nexting thread. */
7132 stepping_thread = NULL;
7134 ALL_NON_EXITED_THREADS (tp)
7136 /* Ignore threads of processes the caller is not
7139 && ptid_get_pid (tp->ptid) != ptid_get_pid (ecs->ptid))
7142 /* When stepping over a breakpoint, we lock all threads
7143 except the one that needs to move past the breakpoint.
7144 If a non-event thread has this set, the "incomplete
7145 step-over" check above should have caught it earlier. */
7146 if (tp->control.trap_expected)
7148 internal_error (__FILE__, __LINE__,
7149 "[%s] has inconsistent state: "
7150 "trap_expected=%d\n",
7151 target_pid_to_str (tp->ptid),
7152 tp->control.trap_expected);
7155 /* Did we find the stepping thread? */
7156 if (tp->control.step_range_end)
7158 /* Yep. There should only one though. */
7159 gdb_assert (stepping_thread == NULL);
7161 /* The event thread is handled at the top, before we
7163 gdb_assert (tp != ecs->event_thread);
7165 /* If some thread other than the event thread is
7166 stepping, then scheduler locking can't be in effect,
7167 otherwise we wouldn't have resumed the current event
7168 thread in the first place. */
7169 gdb_assert (!schedlock_applies (tp));
7171 stepping_thread = tp;
7175 if (stepping_thread != NULL)
7178 fprintf_unfiltered (gdb_stdlog,
7179 "infrun: switching back to stepped thread\n");
7181 if (keep_going_stepped_thread (stepping_thread))
7183 prepare_to_wait (ecs);
7192 /* Set a previously stepped thread back to stepping. Returns true on
7193 success, false if the resume is not possible (e.g., the thread
7197 keep_going_stepped_thread (struct thread_info *tp)
7199 struct frame_info *frame;
7200 struct execution_control_state ecss;
7201 struct execution_control_state *ecs = &ecss;
7203 /* If the stepping thread exited, then don't try to switch back and
7204 resume it, which could fail in several different ways depending
7205 on the target. Instead, just keep going.
7207 We can find a stepping dead thread in the thread list in two
7210 - The target supports thread exit events, and when the target
7211 tries to delete the thread from the thread list, inferior_ptid
7212 pointed at the exiting thread. In such case, calling
7213 delete_thread does not really remove the thread from the list;
7214 instead, the thread is left listed, with 'exited' state.
7216 - The target's debug interface does not support thread exit
7217 events, and so we have no idea whatsoever if the previously
7218 stepping thread is still alive. For that reason, we need to
7219 synchronously query the target now. */
7221 if (is_exited (tp->ptid)
7222 || !target_thread_alive (tp->ptid))
7225 fprintf_unfiltered (gdb_stdlog,
7226 "infrun: not resuming previously "
7227 "stepped thread, it has vanished\n");
7229 delete_thread (tp->ptid);
7234 fprintf_unfiltered (gdb_stdlog,
7235 "infrun: resuming previously stepped thread\n");
7237 reset_ecs (ecs, tp);
7238 switch_to_thread (tp->ptid);
7240 stop_pc = regcache_read_pc (get_thread_regcache (tp->ptid));
7241 frame = get_current_frame ();
7243 /* If the PC of the thread we were trying to single-step has
7244 changed, then that thread has trapped or been signaled, but the
7245 event has not been reported to GDB yet. Re-poll the target
7246 looking for this particular thread's event (i.e. temporarily
7247 enable schedlock) by:
7249 - setting a break at the current PC
7250 - resuming that particular thread, only (by setting trap
7253 This prevents us continuously moving the single-step breakpoint
7254 forward, one instruction at a time, overstepping. */
7256 if (stop_pc != tp->prev_pc)
7261 fprintf_unfiltered (gdb_stdlog,
7262 "infrun: expected thread advanced also (%s -> %s)\n",
7263 paddress (target_gdbarch (), tp->prev_pc),
7264 paddress (target_gdbarch (), stop_pc));
7266 /* Clear the info of the previous step-over, as it's no longer
7267 valid (if the thread was trying to step over a breakpoint, it
7268 has already succeeded). It's what keep_going would do too,
7269 if we called it. Do this before trying to insert the sss
7270 breakpoint, otherwise if we were previously trying to step
7271 over this exact address in another thread, the breakpoint is
7273 clear_step_over_info ();
7274 tp->control.trap_expected = 0;
7276 insert_single_step_breakpoint (get_frame_arch (frame),
7277 get_frame_address_space (frame),
7281 resume_ptid = internal_resume_ptid (tp->control.stepping_command);
7282 do_target_resume (resume_ptid, 0, GDB_SIGNAL_0);
7287 fprintf_unfiltered (gdb_stdlog,
7288 "infrun: expected thread still hasn't advanced\n");
7290 keep_going_pass_signal (ecs);
7295 /* Is thread TP in the middle of (software or hardware)
7296 single-stepping? (Note the result of this function must never be
7297 passed directly as target_resume's STEP parameter.) */
7300 currently_stepping (struct thread_info *tp)
7302 return ((tp->control.step_range_end
7303 && tp->control.step_resume_breakpoint == NULL)
7304 || tp->control.trap_expected
7305 || tp->stepped_breakpoint
7306 || bpstat_should_step ());
7309 /* Inferior has stepped into a subroutine call with source code that
7310 we should not step over. Do step to the first line of code in
7314 handle_step_into_function (struct gdbarch *gdbarch,
7315 struct execution_control_state *ecs)
7317 struct compunit_symtab *cust;
7318 struct symtab_and_line stop_func_sal, sr_sal;
7320 fill_in_stop_func (gdbarch, ecs);
7322 cust = find_pc_compunit_symtab (stop_pc);
7323 if (cust != NULL && compunit_language (cust) != language_asm)
7324 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
7325 ecs->stop_func_start);
7327 stop_func_sal = find_pc_line (ecs->stop_func_start, 0);
7328 /* Use the step_resume_break to step until the end of the prologue,
7329 even if that involves jumps (as it seems to on the vax under
7331 /* If the prologue ends in the middle of a source line, continue to
7332 the end of that source line (if it is still within the function).
7333 Otherwise, just go to end of prologue. */
7334 if (stop_func_sal.end
7335 && stop_func_sal.pc != ecs->stop_func_start
7336 && stop_func_sal.end < ecs->stop_func_end)
7337 ecs->stop_func_start = stop_func_sal.end;
7339 /* Architectures which require breakpoint adjustment might not be able
7340 to place a breakpoint at the computed address. If so, the test
7341 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7342 ecs->stop_func_start to an address at which a breakpoint may be
7343 legitimately placed.
7345 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7346 made, GDB will enter an infinite loop when stepping through
7347 optimized code consisting of VLIW instructions which contain
7348 subinstructions corresponding to different source lines. On
7349 FR-V, it's not permitted to place a breakpoint on any but the
7350 first subinstruction of a VLIW instruction. When a breakpoint is
7351 set, GDB will adjust the breakpoint address to the beginning of
7352 the VLIW instruction. Thus, we need to make the corresponding
7353 adjustment here when computing the stop address. */
7355 if (gdbarch_adjust_breakpoint_address_p (gdbarch))
7357 ecs->stop_func_start
7358 = gdbarch_adjust_breakpoint_address (gdbarch,
7359 ecs->stop_func_start);
7362 if (ecs->stop_func_start == stop_pc)
7364 /* We are already there: stop now. */
7365 end_stepping_range (ecs);
7370 /* Put the step-breakpoint there and go until there. */
7371 init_sal (&sr_sal); /* initialize to zeroes */
7372 sr_sal.pc = ecs->stop_func_start;
7373 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
7374 sr_sal.pspace = get_frame_program_space (get_current_frame ());
7376 /* Do not specify what the fp should be when we stop since on
7377 some machines the prologue is where the new fp value is
7379 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal, null_frame_id);
7381 /* And make sure stepping stops right away then. */
7382 ecs->event_thread->control.step_range_end
7383 = ecs->event_thread->control.step_range_start;
7388 /* Inferior has stepped backward into a subroutine call with source
7389 code that we should not step over. Do step to the beginning of the
7390 last line of code in it. */
7393 handle_step_into_function_backward (struct gdbarch *gdbarch,
7394 struct execution_control_state *ecs)
7396 struct compunit_symtab *cust;
7397 struct symtab_and_line stop_func_sal;
7399 fill_in_stop_func (gdbarch, ecs);
7401 cust = find_pc_compunit_symtab (stop_pc);
7402 if (cust != NULL && compunit_language (cust) != language_asm)
7403 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
7404 ecs->stop_func_start);
7406 stop_func_sal = find_pc_line (stop_pc, 0);
7408 /* OK, we're just going to keep stepping here. */
7409 if (stop_func_sal.pc == stop_pc)
7411 /* We're there already. Just stop stepping now. */
7412 end_stepping_range (ecs);
7416 /* Else just reset the step range and keep going.
7417 No step-resume breakpoint, they don't work for
7418 epilogues, which can have multiple entry paths. */
7419 ecs->event_thread->control.step_range_start = stop_func_sal.pc;
7420 ecs->event_thread->control.step_range_end = stop_func_sal.end;
7426 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7427 This is used to both functions and to skip over code. */
7430 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch *gdbarch,
7431 struct symtab_and_line sr_sal,
7432 struct frame_id sr_id,
7433 enum bptype sr_type)
7435 /* There should never be more than one step-resume or longjmp-resume
7436 breakpoint per thread, so we should never be setting a new
7437 step_resume_breakpoint when one is already active. */
7438 gdb_assert (inferior_thread ()->control.step_resume_breakpoint == NULL);
7439 gdb_assert (sr_type == bp_step_resume || sr_type == bp_hp_step_resume);
7442 fprintf_unfiltered (gdb_stdlog,
7443 "infrun: inserting step-resume breakpoint at %s\n",
7444 paddress (gdbarch, sr_sal.pc));
7446 inferior_thread ()->control.step_resume_breakpoint
7447 = set_momentary_breakpoint (gdbarch, sr_sal, sr_id, sr_type);
7451 insert_step_resume_breakpoint_at_sal (struct gdbarch *gdbarch,
7452 struct symtab_and_line sr_sal,
7453 struct frame_id sr_id)
7455 insert_step_resume_breakpoint_at_sal_1 (gdbarch,
7460 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7461 This is used to skip a potential signal handler.
7463 This is called with the interrupted function's frame. The signal
7464 handler, when it returns, will resume the interrupted function at
7468 insert_hp_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
7470 struct symtab_and_line sr_sal;
7471 struct gdbarch *gdbarch;
7473 gdb_assert (return_frame != NULL);
7474 init_sal (&sr_sal); /* initialize to zeros */
7476 gdbarch = get_frame_arch (return_frame);
7477 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch, get_frame_pc (return_frame));
7478 sr_sal.section = find_pc_overlay (sr_sal.pc);
7479 sr_sal.pspace = get_frame_program_space (return_frame);
7481 insert_step_resume_breakpoint_at_sal_1 (gdbarch, sr_sal,
7482 get_stack_frame_id (return_frame),
7486 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7487 is used to skip a function after stepping into it (for "next" or if
7488 the called function has no debugging information).
7490 The current function has almost always been reached by single
7491 stepping a call or return instruction. NEXT_FRAME belongs to the
7492 current function, and the breakpoint will be set at the caller's
7495 This is a separate function rather than reusing
7496 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7497 get_prev_frame, which may stop prematurely (see the implementation
7498 of frame_unwind_caller_id for an example). */
7501 insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame)
7503 struct symtab_and_line sr_sal;
7504 struct gdbarch *gdbarch;
7506 /* We shouldn't have gotten here if we don't know where the call site
7508 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame)));
7510 init_sal (&sr_sal); /* initialize to zeros */
7512 gdbarch = frame_unwind_caller_arch (next_frame);
7513 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch,
7514 frame_unwind_caller_pc (next_frame));
7515 sr_sal.section = find_pc_overlay (sr_sal.pc);
7516 sr_sal.pspace = frame_unwind_program_space (next_frame);
7518 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal,
7519 frame_unwind_caller_id (next_frame));
7522 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7523 new breakpoint at the target of a jmp_buf. The handling of
7524 longjmp-resume uses the same mechanisms used for handling
7525 "step-resume" breakpoints. */
7528 insert_longjmp_resume_breakpoint (struct gdbarch *gdbarch, CORE_ADDR pc)
7530 /* There should never be more than one longjmp-resume breakpoint per
7531 thread, so we should never be setting a new
7532 longjmp_resume_breakpoint when one is already active. */
7533 gdb_assert (inferior_thread ()->control.exception_resume_breakpoint == NULL);
7536 fprintf_unfiltered (gdb_stdlog,
7537 "infrun: inserting longjmp-resume breakpoint at %s\n",
7538 paddress (gdbarch, pc));
7540 inferior_thread ()->control.exception_resume_breakpoint =
7541 set_momentary_breakpoint_at_pc (gdbarch, pc, bp_longjmp_resume);
7544 /* Insert an exception resume breakpoint. TP is the thread throwing
7545 the exception. The block B is the block of the unwinder debug hook
7546 function. FRAME is the frame corresponding to the call to this
7547 function. SYM is the symbol of the function argument holding the
7548 target PC of the exception. */
7551 insert_exception_resume_breakpoint (struct thread_info *tp,
7552 const struct block *b,
7553 struct frame_info *frame,
7558 struct block_symbol vsym;
7559 struct value *value;
7561 struct breakpoint *bp;
7563 vsym = lookup_symbol (SYMBOL_LINKAGE_NAME (sym), b, VAR_DOMAIN, NULL);
7564 value = read_var_value (vsym.symbol, vsym.block, frame);
7565 /* If the value was optimized out, revert to the old behavior. */
7566 if (! value_optimized_out (value))
7568 handler = value_as_address (value);
7571 fprintf_unfiltered (gdb_stdlog,
7572 "infrun: exception resume at %lx\n",
7573 (unsigned long) handler);
7575 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
7576 handler, bp_exception_resume);
7578 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7581 bp->thread = tp->global_num;
7582 inferior_thread ()->control.exception_resume_breakpoint = bp;
7585 CATCH (e, RETURN_MASK_ERROR)
7587 /* We want to ignore errors here. */
7592 /* A helper for check_exception_resume that sets an
7593 exception-breakpoint based on a SystemTap probe. */
7596 insert_exception_resume_from_probe (struct thread_info *tp,
7597 const struct bound_probe *probe,
7598 struct frame_info *frame)
7600 struct value *arg_value;
7602 struct breakpoint *bp;
7604 arg_value = probe_safe_evaluate_at_pc (frame, 1);
7608 handler = value_as_address (arg_value);
7611 fprintf_unfiltered (gdb_stdlog,
7612 "infrun: exception resume at %s\n",
7613 paddress (get_objfile_arch (probe->objfile),
7616 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
7617 handler, bp_exception_resume);
7618 bp->thread = tp->global_num;
7619 inferior_thread ()->control.exception_resume_breakpoint = bp;
7622 /* This is called when an exception has been intercepted. Check to
7623 see whether the exception's destination is of interest, and if so,
7624 set an exception resume breakpoint there. */
7627 check_exception_resume (struct execution_control_state *ecs,
7628 struct frame_info *frame)
7630 struct bound_probe probe;
7631 struct symbol *func;
7633 /* First see if this exception unwinding breakpoint was set via a
7634 SystemTap probe point. If so, the probe has two arguments: the
7635 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7636 set a breakpoint there. */
7637 probe = find_probe_by_pc (get_frame_pc (frame));
7640 insert_exception_resume_from_probe (ecs->event_thread, &probe, frame);
7644 func = get_frame_function (frame);
7650 const struct block *b;
7651 struct block_iterator iter;
7655 /* The exception breakpoint is a thread-specific breakpoint on
7656 the unwinder's debug hook, declared as:
7658 void _Unwind_DebugHook (void *cfa, void *handler);
7660 The CFA argument indicates the frame to which control is
7661 about to be transferred. HANDLER is the destination PC.
7663 We ignore the CFA and set a temporary breakpoint at HANDLER.
7664 This is not extremely efficient but it avoids issues in gdb
7665 with computing the DWARF CFA, and it also works even in weird
7666 cases such as throwing an exception from inside a signal
7669 b = SYMBOL_BLOCK_VALUE (func);
7670 ALL_BLOCK_SYMBOLS (b, iter, sym)
7672 if (!SYMBOL_IS_ARGUMENT (sym))
7679 insert_exception_resume_breakpoint (ecs->event_thread,
7685 CATCH (e, RETURN_MASK_ERROR)
7692 stop_waiting (struct execution_control_state *ecs)
7695 fprintf_unfiltered (gdb_stdlog, "infrun: stop_waiting\n");
7697 /* Let callers know we don't want to wait for the inferior anymore. */
7698 ecs->wait_some_more = 0;
7700 /* If all-stop, but the target is always in non-stop mode, stop all
7701 threads now that we're presenting the stop to the user. */
7702 if (!non_stop && target_is_non_stop_p ())
7703 stop_all_threads ();
7706 /* Like keep_going, but passes the signal to the inferior, even if the
7707 signal is set to nopass. */
7710 keep_going_pass_signal (struct execution_control_state *ecs)
7712 /* Make sure normal_stop is called if we get a QUIT handled before
7714 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
7716 gdb_assert (ptid_equal (ecs->event_thread->ptid, inferior_ptid));
7717 gdb_assert (!ecs->event_thread->resumed);
7719 /* Save the pc before execution, to compare with pc after stop. */
7720 ecs->event_thread->prev_pc
7721 = regcache_read_pc (get_thread_regcache (ecs->ptid));
7723 if (ecs->event_thread->control.trap_expected)
7725 struct thread_info *tp = ecs->event_thread;
7728 fprintf_unfiltered (gdb_stdlog,
7729 "infrun: %s has trap_expected set, "
7730 "resuming to collect trap\n",
7731 target_pid_to_str (tp->ptid));
7733 /* We haven't yet gotten our trap, and either: intercepted a
7734 non-signal event (e.g., a fork); or took a signal which we
7735 are supposed to pass through to the inferior. Simply
7737 discard_cleanups (old_cleanups);
7738 resume (ecs->event_thread->suspend.stop_signal);
7740 else if (step_over_info_valid_p ())
7742 /* Another thread is stepping over a breakpoint in-line. If
7743 this thread needs a step-over too, queue the request. In
7744 either case, this resume must be deferred for later. */
7745 struct thread_info *tp = ecs->event_thread;
7747 if (ecs->hit_singlestep_breakpoint
7748 || thread_still_needs_step_over (tp))
7751 fprintf_unfiltered (gdb_stdlog,
7752 "infrun: step-over already in progress: "
7753 "step-over for %s deferred\n",
7754 target_pid_to_str (tp->ptid));
7755 thread_step_over_chain_enqueue (tp);
7760 fprintf_unfiltered (gdb_stdlog,
7761 "infrun: step-over in progress: "
7762 "resume of %s deferred\n",
7763 target_pid_to_str (tp->ptid));
7766 discard_cleanups (old_cleanups);
7770 struct regcache *regcache = get_current_regcache ();
7773 step_over_what step_what;
7775 /* Either the trap was not expected, but we are continuing
7776 anyway (if we got a signal, the user asked it be passed to
7779 We got our expected trap, but decided we should resume from
7782 We're going to run this baby now!
7784 Note that insert_breakpoints won't try to re-insert
7785 already inserted breakpoints. Therefore, we don't
7786 care if breakpoints were already inserted, or not. */
7788 /* If we need to step over a breakpoint, and we're not using
7789 displaced stepping to do so, insert all breakpoints
7790 (watchpoints, etc.) but the one we're stepping over, step one
7791 instruction, and then re-insert the breakpoint when that step
7794 step_what = thread_still_needs_step_over (ecs->event_thread);
7796 remove_bp = (ecs->hit_singlestep_breakpoint
7797 || (step_what & STEP_OVER_BREAKPOINT));
7798 remove_wps = (step_what & STEP_OVER_WATCHPOINT);
7800 /* We can't use displaced stepping if we need to step past a
7801 watchpoint. The instruction copied to the scratch pad would
7802 still trigger the watchpoint. */
7804 && (remove_wps || !use_displaced_stepping (ecs->event_thread)))
7806 set_step_over_info (get_regcache_aspace (regcache),
7807 regcache_read_pc (regcache), remove_wps,
7808 ecs->event_thread->global_num);
7810 else if (remove_wps)
7811 set_step_over_info (NULL, 0, remove_wps, -1);
7813 /* If we now need to do an in-line step-over, we need to stop
7814 all other threads. Note this must be done before
7815 insert_breakpoints below, because that removes the breakpoint
7816 we're about to step over, otherwise other threads could miss
7818 if (step_over_info_valid_p () && target_is_non_stop_p ())
7819 stop_all_threads ();
7821 /* Stop stepping if inserting breakpoints fails. */
7824 insert_breakpoints ();
7826 CATCH (e, RETURN_MASK_ERROR)
7828 exception_print (gdb_stderr, e);
7830 discard_cleanups (old_cleanups);
7835 ecs->event_thread->control.trap_expected = (remove_bp || remove_wps);
7837 discard_cleanups (old_cleanups);
7838 resume (ecs->event_thread->suspend.stop_signal);
7841 prepare_to_wait (ecs);
7844 /* Called when we should continue running the inferior, because the
7845 current event doesn't cause a user visible stop. This does the
7846 resuming part; waiting for the next event is done elsewhere. */
7849 keep_going (struct execution_control_state *ecs)
7851 if (ecs->event_thread->control.trap_expected
7852 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
7853 ecs->event_thread->control.trap_expected = 0;
7855 if (!signal_program[ecs->event_thread->suspend.stop_signal])
7856 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
7857 keep_going_pass_signal (ecs);
7860 /* This function normally comes after a resume, before
7861 handle_inferior_event exits. It takes care of any last bits of
7862 housekeeping, and sets the all-important wait_some_more flag. */
7865 prepare_to_wait (struct execution_control_state *ecs)
7868 fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n");
7870 ecs->wait_some_more = 1;
7872 if (!target_is_async_p ())
7873 mark_infrun_async_event_handler ();
7876 /* We are done with the step range of a step/next/si/ni command.
7877 Called once for each n of a "step n" operation. */
7880 end_stepping_range (struct execution_control_state *ecs)
7882 ecs->event_thread->control.stop_step = 1;
7886 /* Several print_*_reason functions to print why the inferior has stopped.
7887 We always print something when the inferior exits, or receives a signal.
7888 The rest of the cases are dealt with later on in normal_stop and
7889 print_it_typical. Ideally there should be a call to one of these
7890 print_*_reason functions functions from handle_inferior_event each time
7891 stop_waiting is called.
7893 Note that we don't call these directly, instead we delegate that to
7894 the interpreters, through observers. Interpreters then call these
7895 with whatever uiout is right. */
7898 print_end_stepping_range_reason (struct ui_out *uiout)
7900 /* For CLI-like interpreters, print nothing. */
7902 if (uiout->is_mi_like_p ())
7904 uiout->field_string ("reason",
7905 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE));
7910 print_signal_exited_reason (struct ui_out *uiout, enum gdb_signal siggnal)
7912 annotate_signalled ();
7913 if (uiout->is_mi_like_p ())
7915 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED));
7916 uiout->text ("\nProgram terminated with signal ");
7917 annotate_signal_name ();
7918 uiout->field_string ("signal-name",
7919 gdb_signal_to_name (siggnal));
7920 annotate_signal_name_end ();
7922 annotate_signal_string ();
7923 uiout->field_string ("signal-meaning",
7924 gdb_signal_to_string (siggnal));
7925 annotate_signal_string_end ();
7926 uiout->text (".\n");
7927 uiout->text ("The program no longer exists.\n");
7931 print_exited_reason (struct ui_out *uiout, int exitstatus)
7933 struct inferior *inf = current_inferior ();
7934 const char *pidstr = target_pid_to_str (pid_to_ptid (inf->pid));
7936 annotate_exited (exitstatus);
7939 if (uiout->is_mi_like_p ())
7940 uiout->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED));
7941 uiout->text ("[Inferior ");
7942 uiout->text (plongest (inf->num));
7944 uiout->text (pidstr);
7945 uiout->text (") exited with code ");
7946 uiout->field_fmt ("exit-code", "0%o", (unsigned int) exitstatus);
7947 uiout->text ("]\n");
7951 if (uiout->is_mi_like_p ())
7953 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY));
7954 uiout->text ("[Inferior ");
7955 uiout->text (plongest (inf->num));
7957 uiout->text (pidstr);
7958 uiout->text (") exited normally]\n");
7962 /* Some targets/architectures can do extra processing/display of
7963 segmentation faults. E.g., Intel MPX boundary faults.
7964 Call the architecture dependent function to handle the fault. */
7967 handle_segmentation_fault (struct ui_out *uiout)
7969 struct regcache *regcache = get_current_regcache ();
7970 struct gdbarch *gdbarch = get_regcache_arch (regcache);
7972 if (gdbarch_handle_segmentation_fault_p (gdbarch))
7973 gdbarch_handle_segmentation_fault (gdbarch, uiout);
7977 print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal)
7979 struct thread_info *thr = inferior_thread ();
7983 if (uiout->is_mi_like_p ())
7985 else if (show_thread_that_caused_stop ())
7989 uiout->text ("\nThread ");
7990 uiout->field_fmt ("thread-id", "%s", print_thread_id (thr));
7992 name = thr->name != NULL ? thr->name : target_thread_name (thr);
7995 uiout->text (" \"");
7996 uiout->field_fmt ("name", "%s", name);
8001 uiout->text ("\nProgram");
8003 if (siggnal == GDB_SIGNAL_0 && !uiout->is_mi_like_p ())
8004 uiout->text (" stopped");
8007 uiout->text (" received signal ");
8008 annotate_signal_name ();
8009 if (uiout->is_mi_like_p ())
8011 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
8012 uiout->field_string ("signal-name", gdb_signal_to_name (siggnal));
8013 annotate_signal_name_end ();
8015 annotate_signal_string ();
8016 uiout->field_string ("signal-meaning", gdb_signal_to_string (siggnal));
8018 if (siggnal == GDB_SIGNAL_SEGV)
8019 handle_segmentation_fault (uiout);
8021 annotate_signal_string_end ();
8023 uiout->text (".\n");
8027 print_no_history_reason (struct ui_out *uiout)
8029 uiout->text ("\nNo more reverse-execution history.\n");
8032 /* Print current location without a level number, if we have changed
8033 functions or hit a breakpoint. Print source line if we have one.
8034 bpstat_print contains the logic deciding in detail what to print,
8035 based on the event(s) that just occurred. */
8038 print_stop_location (struct target_waitstatus *ws)
8041 enum print_what source_flag;
8042 int do_frame_printing = 1;
8043 struct thread_info *tp = inferior_thread ();
8045 bpstat_ret = bpstat_print (tp->control.stop_bpstat, ws->kind);
8049 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8050 should) carry around the function and does (or should) use
8051 that when doing a frame comparison. */
8052 if (tp->control.stop_step
8053 && frame_id_eq (tp->control.step_frame_id,
8054 get_frame_id (get_current_frame ()))
8055 && tp->control.step_start_function == find_pc_function (stop_pc))
8057 /* Finished step, just print source line. */
8058 source_flag = SRC_LINE;
8062 /* Print location and source line. */
8063 source_flag = SRC_AND_LOC;
8066 case PRINT_SRC_AND_LOC:
8067 /* Print location and source line. */
8068 source_flag = SRC_AND_LOC;
8070 case PRINT_SRC_ONLY:
8071 source_flag = SRC_LINE;
8074 /* Something bogus. */
8075 source_flag = SRC_LINE;
8076 do_frame_printing = 0;
8079 internal_error (__FILE__, __LINE__, _("Unknown value."));
8082 /* The behavior of this routine with respect to the source
8084 SRC_LINE: Print only source line
8085 LOCATION: Print only location
8086 SRC_AND_LOC: Print location and source line. */
8087 if (do_frame_printing)
8088 print_stack_frame (get_selected_frame (NULL), 0, source_flag, 1);
8094 print_stop_event (struct ui_out *uiout)
8096 struct target_waitstatus last;
8098 struct thread_info *tp;
8100 get_last_target_status (&last_ptid, &last);
8103 scoped_restore save_uiout = make_scoped_restore (¤t_uiout, uiout);
8105 print_stop_location (&last);
8107 /* Display the auto-display expressions. */
8111 tp = inferior_thread ();
8112 if (tp->thread_fsm != NULL
8113 && thread_fsm_finished_p (tp->thread_fsm))
8115 struct return_value_info *rv;
8117 rv = thread_fsm_return_value (tp->thread_fsm);
8119 print_return_value (uiout, rv);
8126 maybe_remove_breakpoints (void)
8128 if (!breakpoints_should_be_inserted_now () && target_has_execution)
8130 if (remove_breakpoints ())
8132 target_terminal_ours_for_output ();
8133 printf_filtered (_("Cannot remove breakpoints because "
8134 "program is no longer writable.\nFurther "
8135 "execution is probably impossible.\n"));
8140 /* The execution context that just caused a normal stop. */
8147 /* The event PTID. */
8151 /* If stopp for a thread event, this is the thread that caused the
8153 struct thread_info *thread;
8155 /* The inferior that caused the stop. */
8159 /* Returns a new stop context. If stopped for a thread event, this
8160 takes a strong reference to the thread. */
8162 static struct stop_context *
8163 save_stop_context (void)
8165 struct stop_context *sc = XNEW (struct stop_context);
8167 sc->stop_id = get_stop_id ();
8168 sc->ptid = inferior_ptid;
8169 sc->inf_num = current_inferior ()->num;
8171 if (!ptid_equal (inferior_ptid, null_ptid))
8173 /* Take a strong reference so that the thread can't be deleted
8175 sc->thread = inferior_thread ();
8176 sc->thread->incref ();
8184 /* Release a stop context previously created with save_stop_context.
8185 Releases the strong reference to the thread as well. */
8188 release_stop_context_cleanup (void *arg)
8190 struct stop_context *sc = (struct stop_context *) arg;
8192 if (sc->thread != NULL)
8193 sc->thread->decref ();
8197 /* Return true if the current context no longer matches the saved stop
8201 stop_context_changed (struct stop_context *prev)
8203 if (!ptid_equal (prev->ptid, inferior_ptid))
8205 if (prev->inf_num != current_inferior ()->num)
8207 if (prev->thread != NULL && prev->thread->state != THREAD_STOPPED)
8209 if (get_stop_id () != prev->stop_id)
8219 struct target_waitstatus last;
8221 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
8224 get_last_target_status (&last_ptid, &last);
8228 /* If an exception is thrown from this point on, make sure to
8229 propagate GDB's knowledge of the executing state to the
8230 frontend/user running state. A QUIT is an easy exception to see
8231 here, so do this before any filtered output. */
8233 make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
8234 else if (last.kind == TARGET_WAITKIND_SIGNALLED
8235 || last.kind == TARGET_WAITKIND_EXITED)
8237 /* On some targets, we may still have live threads in the
8238 inferior when we get a process exit event. E.g., for
8239 "checkpoint", when the current checkpoint/fork exits,
8240 linux-fork.c automatically switches to another fork from
8241 within target_mourn_inferior. */
8242 if (!ptid_equal (inferior_ptid, null_ptid))
8244 pid_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
8245 make_cleanup (finish_thread_state_cleanup, &pid_ptid);
8248 else if (last.kind != TARGET_WAITKIND_NO_RESUMED)
8249 make_cleanup (finish_thread_state_cleanup, &inferior_ptid);
8251 /* As we're presenting a stop, and potentially removing breakpoints,
8252 update the thread list so we can tell whether there are threads
8253 running on the target. With target remote, for example, we can
8254 only learn about new threads when we explicitly update the thread
8255 list. Do this before notifying the interpreters about signal
8256 stops, end of stepping ranges, etc., so that the "new thread"
8257 output is emitted before e.g., "Program received signal FOO",
8258 instead of after. */
8259 update_thread_list ();
8261 if (last.kind == TARGET_WAITKIND_STOPPED && stopped_by_random_signal)
8262 observer_notify_signal_received (inferior_thread ()->suspend.stop_signal);
8264 /* As with the notification of thread events, we want to delay
8265 notifying the user that we've switched thread context until
8266 the inferior actually stops.
8268 There's no point in saying anything if the inferior has exited.
8269 Note that SIGNALLED here means "exited with a signal", not
8270 "received a signal".
8272 Also skip saying anything in non-stop mode. In that mode, as we
8273 don't want GDB to switch threads behind the user's back, to avoid
8274 races where the user is typing a command to apply to thread x,
8275 but GDB switches to thread y before the user finishes entering
8276 the command, fetch_inferior_event installs a cleanup to restore
8277 the current thread back to the thread the user had selected right
8278 after this event is handled, so we're not really switching, only
8279 informing of a stop. */
8281 && !ptid_equal (previous_inferior_ptid, inferior_ptid)
8282 && target_has_execution
8283 && last.kind != TARGET_WAITKIND_SIGNALLED
8284 && last.kind != TARGET_WAITKIND_EXITED
8285 && last.kind != TARGET_WAITKIND_NO_RESUMED)
8287 SWITCH_THRU_ALL_UIS ()
8289 target_terminal_ours_for_output ();
8290 printf_filtered (_("[Switching to %s]\n"),
8291 target_pid_to_str (inferior_ptid));
8292 annotate_thread_changed ();
8294 previous_inferior_ptid = inferior_ptid;
8297 if (last.kind == TARGET_WAITKIND_NO_RESUMED)
8299 SWITCH_THRU_ALL_UIS ()
8300 if (current_ui->prompt_state == PROMPT_BLOCKED)
8302 target_terminal_ours_for_output ();
8303 printf_filtered (_("No unwaited-for children left.\n"));
8307 /* Note: this depends on the update_thread_list call above. */
8308 maybe_remove_breakpoints ();
8310 /* If an auto-display called a function and that got a signal,
8311 delete that auto-display to avoid an infinite recursion. */
8313 if (stopped_by_random_signal)
8314 disable_current_display ();
8316 SWITCH_THRU_ALL_UIS ()
8318 async_enable_stdin ();
8321 /* Let the user/frontend see the threads as stopped. */
8322 do_cleanups (old_chain);
8324 /* Select innermost stack frame - i.e., current frame is frame 0,
8325 and current location is based on that. Handle the case where the
8326 dummy call is returning after being stopped. E.g. the dummy call
8327 previously hit a breakpoint. (If the dummy call returns
8328 normally, we won't reach here.) Do this before the stop hook is
8329 run, so that it doesn't get to see the temporary dummy frame,
8330 which is not where we'll present the stop. */
8331 if (has_stack_frames ())
8333 if (stop_stack_dummy == STOP_STACK_DUMMY)
8335 /* Pop the empty frame that contains the stack dummy. This
8336 also restores inferior state prior to the call (struct
8337 infcall_suspend_state). */
8338 struct frame_info *frame = get_current_frame ();
8340 gdb_assert (get_frame_type (frame) == DUMMY_FRAME);
8342 /* frame_pop calls reinit_frame_cache as the last thing it
8343 does which means there's now no selected frame. */
8346 select_frame (get_current_frame ());
8348 /* Set the current source location. */
8349 set_current_sal_from_frame (get_current_frame ());
8352 /* Look up the hook_stop and run it (CLI internally handles problem
8353 of stop_command's pre-hook not existing). */
8354 if (stop_command != NULL)
8356 struct stop_context *saved_context = save_stop_context ();
8357 struct cleanup *old_chain
8358 = make_cleanup (release_stop_context_cleanup, saved_context);
8360 catch_errors (hook_stop_stub, stop_command,
8361 "Error while running hook_stop:\n", RETURN_MASK_ALL);
8363 /* If the stop hook resumes the target, then there's no point in
8364 trying to notify about the previous stop; its context is
8365 gone. Likewise if the command switches thread or inferior --
8366 the observers would print a stop for the wrong
8368 if (stop_context_changed (saved_context))
8370 do_cleanups (old_chain);
8373 do_cleanups (old_chain);
8376 /* Notify observers about the stop. This is where the interpreters
8377 print the stop event. */
8378 if (!ptid_equal (inferior_ptid, null_ptid))
8379 observer_notify_normal_stop (inferior_thread ()->control.stop_bpstat,
8382 observer_notify_normal_stop (NULL, stop_print_frame);
8384 annotate_stopped ();
8386 if (target_has_execution)
8388 if (last.kind != TARGET_WAITKIND_SIGNALLED
8389 && last.kind != TARGET_WAITKIND_EXITED)
8390 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8391 Delete any breakpoint that is to be deleted at the next stop. */
8392 breakpoint_auto_delete (inferior_thread ()->control.stop_bpstat);
8395 /* Try to get rid of automatically added inferiors that are no
8396 longer needed. Keeping those around slows down things linearly.
8397 Note that this never removes the current inferior. */
8404 hook_stop_stub (void *cmd)
8406 execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
8411 signal_stop_state (int signo)
8413 return signal_stop[signo];
8417 signal_print_state (int signo)
8419 return signal_print[signo];
8423 signal_pass_state (int signo)
8425 return signal_program[signo];
8429 signal_cache_update (int signo)
8433 for (signo = 0; signo < (int) GDB_SIGNAL_LAST; signo++)
8434 signal_cache_update (signo);
8439 signal_pass[signo] = (signal_stop[signo] == 0
8440 && signal_print[signo] == 0
8441 && signal_program[signo] == 1
8442 && signal_catch[signo] == 0);
8446 signal_stop_update (int signo, int state)
8448 int ret = signal_stop[signo];
8450 signal_stop[signo] = state;
8451 signal_cache_update (signo);
8456 signal_print_update (int signo, int state)
8458 int ret = signal_print[signo];
8460 signal_print[signo] = state;
8461 signal_cache_update (signo);
8466 signal_pass_update (int signo, int state)
8468 int ret = signal_program[signo];
8470 signal_program[signo] = state;
8471 signal_cache_update (signo);
8475 /* Update the global 'signal_catch' from INFO and notify the
8479 signal_catch_update (const unsigned int *info)
8483 for (i = 0; i < GDB_SIGNAL_LAST; ++i)
8484 signal_catch[i] = info[i] > 0;
8485 signal_cache_update (-1);
8486 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
8490 sig_print_header (void)
8492 printf_filtered (_("Signal Stop\tPrint\tPass "
8493 "to program\tDescription\n"));
8497 sig_print_info (enum gdb_signal oursig)
8499 const char *name = gdb_signal_to_name (oursig);
8500 int name_padding = 13 - strlen (name);
8502 if (name_padding <= 0)
8505 printf_filtered ("%s", name);
8506 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
8507 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
8508 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
8509 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
8510 printf_filtered ("%s\n", gdb_signal_to_string (oursig));
8513 /* Specify how various signals in the inferior should be handled. */
8516 handle_command (char *args, int from_tty)
8519 int digits, wordlen;
8520 int sigfirst, signum, siglast;
8521 enum gdb_signal oursig;
8524 unsigned char *sigs;
8525 struct cleanup *old_chain;
8529 error_no_arg (_("signal to handle"));
8532 /* Allocate and zero an array of flags for which signals to handle. */
8534 nsigs = (int) GDB_SIGNAL_LAST;
8535 sigs = (unsigned char *) alloca (nsigs);
8536 memset (sigs, 0, nsigs);
8538 /* Break the command line up into args. */
8540 argv = gdb_buildargv (args);
8541 old_chain = make_cleanup_freeargv (argv);
8543 /* Walk through the args, looking for signal oursigs, signal names, and
8544 actions. Signal numbers and signal names may be interspersed with
8545 actions, with the actions being performed for all signals cumulatively
8546 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8548 while (*argv != NULL)
8550 wordlen = strlen (*argv);
8551 for (digits = 0; isdigit ((*argv)[digits]); digits++)
8555 sigfirst = siglast = -1;
8557 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
8559 /* Apply action to all signals except those used by the
8560 debugger. Silently skip those. */
8563 siglast = nsigs - 1;
8565 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
8567 SET_SIGS (nsigs, sigs, signal_stop);
8568 SET_SIGS (nsigs, sigs, signal_print);
8570 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
8572 UNSET_SIGS (nsigs, sigs, signal_program);
8574 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
8576 SET_SIGS (nsigs, sigs, signal_print);
8578 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
8580 SET_SIGS (nsigs, sigs, signal_program);
8582 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
8584 UNSET_SIGS (nsigs, sigs, signal_stop);
8586 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
8588 SET_SIGS (nsigs, sigs, signal_program);
8590 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
8592 UNSET_SIGS (nsigs, sigs, signal_print);
8593 UNSET_SIGS (nsigs, sigs, signal_stop);
8595 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
8597 UNSET_SIGS (nsigs, sigs, signal_program);
8599 else if (digits > 0)
8601 /* It is numeric. The numeric signal refers to our own
8602 internal signal numbering from target.h, not to host/target
8603 signal number. This is a feature; users really should be
8604 using symbolic names anyway, and the common ones like
8605 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8607 sigfirst = siglast = (int)
8608 gdb_signal_from_command (atoi (*argv));
8609 if ((*argv)[digits] == '-')
8612 gdb_signal_from_command (atoi ((*argv) + digits + 1));
8614 if (sigfirst > siglast)
8616 /* Bet he didn't figure we'd think of this case... */
8624 oursig = gdb_signal_from_name (*argv);
8625 if (oursig != GDB_SIGNAL_UNKNOWN)
8627 sigfirst = siglast = (int) oursig;
8631 /* Not a number and not a recognized flag word => complain. */
8632 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv);
8636 /* If any signal numbers or symbol names were found, set flags for
8637 which signals to apply actions to. */
8639 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
8641 switch ((enum gdb_signal) signum)
8643 case GDB_SIGNAL_TRAP:
8644 case GDB_SIGNAL_INT:
8645 if (!allsigs && !sigs[signum])
8647 if (query (_("%s is used by the debugger.\n\
8648 Are you sure you want to change it? "),
8649 gdb_signal_to_name ((enum gdb_signal) signum)))
8655 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8656 gdb_flush (gdb_stdout);
8661 case GDB_SIGNAL_DEFAULT:
8662 case GDB_SIGNAL_UNKNOWN:
8663 /* Make sure that "all" doesn't print these. */
8674 for (signum = 0; signum < nsigs; signum++)
8677 signal_cache_update (-1);
8678 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
8679 target_program_signals ((int) GDB_SIGNAL_LAST, signal_program);
8683 /* Show the results. */
8684 sig_print_header ();
8685 for (; signum < nsigs; signum++)
8687 sig_print_info ((enum gdb_signal) signum);
8693 do_cleanups (old_chain);
8696 /* Complete the "handle" command. */
8698 static VEC (char_ptr) *
8699 handle_completer (struct cmd_list_element *ignore,
8700 const char *text, const char *word)
8702 VEC (char_ptr) *vec_signals, *vec_keywords, *return_val;
8703 static const char * const keywords[] =
8717 vec_signals = signal_completer (ignore, text, word);
8718 vec_keywords = complete_on_enum (keywords, word, word);
8720 return_val = VEC_merge (char_ptr, vec_signals, vec_keywords);
8721 VEC_free (char_ptr, vec_signals);
8722 VEC_free (char_ptr, vec_keywords);
8727 gdb_signal_from_command (int num)
8729 if (num >= 1 && num <= 15)
8730 return (enum gdb_signal) num;
8731 error (_("Only signals 1-15 are valid as numeric signals.\n\
8732 Use \"info signals\" for a list of symbolic signals."));
8735 /* Print current contents of the tables set by the handle command.
8736 It is possible we should just be printing signals actually used
8737 by the current target (but for things to work right when switching
8738 targets, all signals should be in the signal tables). */
8741 signals_info (char *signum_exp, int from_tty)
8743 enum gdb_signal oursig;
8745 sig_print_header ();
8749 /* First see if this is a symbol name. */
8750 oursig = gdb_signal_from_name (signum_exp);
8751 if (oursig == GDB_SIGNAL_UNKNOWN)
8753 /* No, try numeric. */
8755 gdb_signal_from_command (parse_and_eval_long (signum_exp));
8757 sig_print_info (oursig);
8761 printf_filtered ("\n");
8762 /* These ugly casts brought to you by the native VAX compiler. */
8763 for (oursig = GDB_SIGNAL_FIRST;
8764 (int) oursig < (int) GDB_SIGNAL_LAST;
8765 oursig = (enum gdb_signal) ((int) oursig + 1))
8769 if (oursig != GDB_SIGNAL_UNKNOWN
8770 && oursig != GDB_SIGNAL_DEFAULT && oursig != GDB_SIGNAL_0)
8771 sig_print_info (oursig);
8774 printf_filtered (_("\nUse the \"handle\" command "
8775 "to change these tables.\n"));
8778 /* The $_siginfo convenience variable is a bit special. We don't know
8779 for sure the type of the value until we actually have a chance to
8780 fetch the data. The type can change depending on gdbarch, so it is
8781 also dependent on which thread you have selected.
8783 1. making $_siginfo be an internalvar that creates a new value on
8786 2. making the value of $_siginfo be an lval_computed value. */
8788 /* This function implements the lval_computed support for reading a
8792 siginfo_value_read (struct value *v)
8794 LONGEST transferred;
8796 /* If we can access registers, so can we access $_siginfo. Likewise
8798 validate_registers_access ();
8801 target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO,
8803 value_contents_all_raw (v),
8805 TYPE_LENGTH (value_type (v)));
8807 if (transferred != TYPE_LENGTH (value_type (v)))
8808 error (_("Unable to read siginfo"));
8811 /* This function implements the lval_computed support for writing a
8815 siginfo_value_write (struct value *v, struct value *fromval)
8817 LONGEST transferred;
8819 /* If we can access registers, so can we access $_siginfo. Likewise
8821 validate_registers_access ();
8823 transferred = target_write (¤t_target,
8824 TARGET_OBJECT_SIGNAL_INFO,
8826 value_contents_all_raw (fromval),
8828 TYPE_LENGTH (value_type (fromval)));
8830 if (transferred != TYPE_LENGTH (value_type (fromval)))
8831 error (_("Unable to write siginfo"));
8834 static const struct lval_funcs siginfo_value_funcs =
8840 /* Return a new value with the correct type for the siginfo object of
8841 the current thread using architecture GDBARCH. Return a void value
8842 if there's no object available. */
8844 static struct value *
8845 siginfo_make_value (struct gdbarch *gdbarch, struct internalvar *var,
8848 if (target_has_stack
8849 && !ptid_equal (inferior_ptid, null_ptid)
8850 && gdbarch_get_siginfo_type_p (gdbarch))
8852 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8854 return allocate_computed_value (type, &siginfo_value_funcs, NULL);
8857 return allocate_value (builtin_type (gdbarch)->builtin_void);
8861 /* infcall_suspend_state contains state about the program itself like its
8862 registers and any signal it received when it last stopped.
8863 This state must be restored regardless of how the inferior function call
8864 ends (either successfully, or after it hits a breakpoint or signal)
8865 if the program is to properly continue where it left off. */
8867 struct infcall_suspend_state
8869 struct thread_suspend_state thread_suspend;
8873 struct regcache *registers;
8875 /* Format of SIGINFO_DATA or NULL if it is not present. */
8876 struct gdbarch *siginfo_gdbarch;
8878 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8879 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8880 content would be invalid. */
8881 gdb_byte *siginfo_data;
8884 struct infcall_suspend_state *
8885 save_infcall_suspend_state (void)
8887 struct infcall_suspend_state *inf_state;
8888 struct thread_info *tp = inferior_thread ();
8889 struct regcache *regcache = get_current_regcache ();
8890 struct gdbarch *gdbarch = get_regcache_arch (regcache);
8891 gdb_byte *siginfo_data = NULL;
8893 if (gdbarch_get_siginfo_type_p (gdbarch))
8895 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8896 size_t len = TYPE_LENGTH (type);
8897 struct cleanup *back_to;
8899 siginfo_data = (gdb_byte *) xmalloc (len);
8900 back_to = make_cleanup (xfree, siginfo_data);
8902 if (target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
8903 siginfo_data, 0, len) == len)
8904 discard_cleanups (back_to);
8907 /* Errors ignored. */
8908 do_cleanups (back_to);
8909 siginfo_data = NULL;
8913 inf_state = XCNEW (struct infcall_suspend_state);
8917 inf_state->siginfo_gdbarch = gdbarch;
8918 inf_state->siginfo_data = siginfo_data;
8921 inf_state->thread_suspend = tp->suspend;
8923 /* run_inferior_call will not use the signal due to its `proceed' call with
8924 GDB_SIGNAL_0 anyway. */
8925 tp->suspend.stop_signal = GDB_SIGNAL_0;
8927 inf_state->stop_pc = stop_pc;
8929 inf_state->registers = regcache_dup (regcache);
8934 /* Restore inferior session state to INF_STATE. */
8937 restore_infcall_suspend_state (struct infcall_suspend_state *inf_state)
8939 struct thread_info *tp = inferior_thread ();
8940 struct regcache *regcache = get_current_regcache ();
8941 struct gdbarch *gdbarch = get_regcache_arch (regcache);
8943 tp->suspend = inf_state->thread_suspend;
8945 stop_pc = inf_state->stop_pc;
8947 if (inf_state->siginfo_gdbarch == gdbarch)
8949 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8951 /* Errors ignored. */
8952 target_write (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
8953 inf_state->siginfo_data, 0, TYPE_LENGTH (type));
8956 /* The inferior can be gone if the user types "print exit(0)"
8957 (and perhaps other times). */
8958 if (target_has_execution)
8959 /* NB: The register write goes through to the target. */
8960 regcache_cpy (regcache, inf_state->registers);
8962 discard_infcall_suspend_state (inf_state);
8966 do_restore_infcall_suspend_state_cleanup (void *state)
8968 restore_infcall_suspend_state ((struct infcall_suspend_state *) state);
8972 make_cleanup_restore_infcall_suspend_state
8973 (struct infcall_suspend_state *inf_state)
8975 return make_cleanup (do_restore_infcall_suspend_state_cleanup, inf_state);
8979 discard_infcall_suspend_state (struct infcall_suspend_state *inf_state)
8981 regcache_xfree (inf_state->registers);
8982 xfree (inf_state->siginfo_data);
8987 get_infcall_suspend_state_regcache (struct infcall_suspend_state *inf_state)
8989 return inf_state->registers;
8992 /* infcall_control_state contains state regarding gdb's control of the
8993 inferior itself like stepping control. It also contains session state like
8994 the user's currently selected frame. */
8996 struct infcall_control_state
8998 struct thread_control_state thread_control;
8999 struct inferior_control_state inferior_control;
9002 enum stop_stack_kind stop_stack_dummy;
9003 int stopped_by_random_signal;
9005 /* ID if the selected frame when the inferior function call was made. */
9006 struct frame_id selected_frame_id;
9009 /* Save all of the information associated with the inferior<==>gdb
9012 struct infcall_control_state *
9013 save_infcall_control_state (void)
9015 struct infcall_control_state *inf_status =
9016 XNEW (struct infcall_control_state);
9017 struct thread_info *tp = inferior_thread ();
9018 struct inferior *inf = current_inferior ();
9020 inf_status->thread_control = tp->control;
9021 inf_status->inferior_control = inf->control;
9023 tp->control.step_resume_breakpoint = NULL;
9024 tp->control.exception_resume_breakpoint = NULL;
9026 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9027 chain. If caller's caller is walking the chain, they'll be happier if we
9028 hand them back the original chain when restore_infcall_control_state is
9030 tp->control.stop_bpstat = bpstat_copy (tp->control.stop_bpstat);
9033 inf_status->stop_stack_dummy = stop_stack_dummy;
9034 inf_status->stopped_by_random_signal = stopped_by_random_signal;
9036 inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL));
9042 restore_selected_frame (void *args)
9044 struct frame_id *fid = (struct frame_id *) args;
9045 struct frame_info *frame;
9047 frame = frame_find_by_id (*fid);
9049 /* If inf_status->selected_frame_id is NULL, there was no previously
9053 warning (_("Unable to restore previously selected frame."));
9057 select_frame (frame);
9062 /* Restore inferior session state to INF_STATUS. */
9065 restore_infcall_control_state (struct infcall_control_state *inf_status)
9067 struct thread_info *tp = inferior_thread ();
9068 struct inferior *inf = current_inferior ();
9070 if (tp->control.step_resume_breakpoint)
9071 tp->control.step_resume_breakpoint->disposition = disp_del_at_next_stop;
9073 if (tp->control.exception_resume_breakpoint)
9074 tp->control.exception_resume_breakpoint->disposition
9075 = disp_del_at_next_stop;
9077 /* Handle the bpstat_copy of the chain. */
9078 bpstat_clear (&tp->control.stop_bpstat);
9080 tp->control = inf_status->thread_control;
9081 inf->control = inf_status->inferior_control;
9084 stop_stack_dummy = inf_status->stop_stack_dummy;
9085 stopped_by_random_signal = inf_status->stopped_by_random_signal;
9087 if (target_has_stack)
9089 /* The point of catch_errors is that if the stack is clobbered,
9090 walking the stack might encounter a garbage pointer and
9091 error() trying to dereference it. */
9093 (restore_selected_frame, &inf_status->selected_frame_id,
9094 "Unable to restore previously selected frame:\n",
9095 RETURN_MASK_ERROR) == 0)
9096 /* Error in restoring the selected frame. Select the innermost
9098 select_frame (get_current_frame ());
9105 do_restore_infcall_control_state_cleanup (void *sts)
9107 restore_infcall_control_state ((struct infcall_control_state *) sts);
9111 make_cleanup_restore_infcall_control_state
9112 (struct infcall_control_state *inf_status)
9114 return make_cleanup (do_restore_infcall_control_state_cleanup, inf_status);
9118 discard_infcall_control_state (struct infcall_control_state *inf_status)
9120 if (inf_status->thread_control.step_resume_breakpoint)
9121 inf_status->thread_control.step_resume_breakpoint->disposition
9122 = disp_del_at_next_stop;
9124 if (inf_status->thread_control.exception_resume_breakpoint)
9125 inf_status->thread_control.exception_resume_breakpoint->disposition
9126 = disp_del_at_next_stop;
9128 /* See save_infcall_control_state for info on stop_bpstat. */
9129 bpstat_clear (&inf_status->thread_control.stop_bpstat);
9134 /* restore_inferior_ptid() will be used by the cleanup machinery
9135 to restore the inferior_ptid value saved in a call to
9136 save_inferior_ptid(). */
9139 restore_inferior_ptid (void *arg)
9141 ptid_t *saved_ptid_ptr = (ptid_t *) arg;
9143 inferior_ptid = *saved_ptid_ptr;
9147 /* Save the value of inferior_ptid so that it may be restored by a
9148 later call to do_cleanups(). Returns the struct cleanup pointer
9149 needed for later doing the cleanup. */
9152 save_inferior_ptid (void)
9154 ptid_t *saved_ptid_ptr = XNEW (ptid_t);
9156 *saved_ptid_ptr = inferior_ptid;
9157 return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
9163 clear_exit_convenience_vars (void)
9165 clear_internalvar (lookup_internalvar ("_exitsignal"));
9166 clear_internalvar (lookup_internalvar ("_exitcode"));
9170 /* User interface for reverse debugging:
9171 Set exec-direction / show exec-direction commands
9172 (returns error unless target implements to_set_exec_direction method). */
9174 enum exec_direction_kind execution_direction = EXEC_FORWARD;
9175 static const char exec_forward[] = "forward";
9176 static const char exec_reverse[] = "reverse";
9177 static const char *exec_direction = exec_forward;
9178 static const char *const exec_direction_names[] = {
9185 set_exec_direction_func (char *args, int from_tty,
9186 struct cmd_list_element *cmd)
9188 if (target_can_execute_reverse)
9190 if (!strcmp (exec_direction, exec_forward))
9191 execution_direction = EXEC_FORWARD;
9192 else if (!strcmp (exec_direction, exec_reverse))
9193 execution_direction = EXEC_REVERSE;
9197 exec_direction = exec_forward;
9198 error (_("Target does not support this operation."));
9203 show_exec_direction_func (struct ui_file *out, int from_tty,
9204 struct cmd_list_element *cmd, const char *value)
9206 switch (execution_direction) {
9208 fprintf_filtered (out, _("Forward.\n"));
9211 fprintf_filtered (out, _("Reverse.\n"));
9214 internal_error (__FILE__, __LINE__,
9215 _("bogus execution_direction value: %d"),
9216 (int) execution_direction);
9221 show_schedule_multiple (struct ui_file *file, int from_tty,
9222 struct cmd_list_element *c, const char *value)
9224 fprintf_filtered (file, _("Resuming the execution of threads "
9225 "of all processes is %s.\n"), value);
9228 /* Implementation of `siginfo' variable. */
9230 static const struct internalvar_funcs siginfo_funcs =
9237 /* Callback for infrun's target events source. This is marked when a
9238 thread has a pending status to process. */
9241 infrun_async_inferior_event_handler (gdb_client_data data)
9243 inferior_event_handler (INF_REG_EVENT, NULL);
9247 _initialize_infrun (void)
9251 struct cmd_list_element *c;
9253 /* Register extra event sources in the event loop. */
9254 infrun_async_inferior_event_token
9255 = create_async_event_handler (infrun_async_inferior_event_handler, NULL);
9257 add_info ("signals", signals_info, _("\
9258 What debugger does when program gets various signals.\n\
9259 Specify a signal as argument to print info on that signal only."));
9260 add_info_alias ("handle", "signals", 0);
9262 c = add_com ("handle", class_run, handle_command, _("\
9263 Specify how to handle signals.\n\
9264 Usage: handle SIGNAL [ACTIONS]\n\
9265 Args are signals and actions to apply to those signals.\n\
9266 If no actions are specified, the current settings for the specified signals\n\
9267 will be displayed instead.\n\
9269 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9270 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9271 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9272 The special arg \"all\" is recognized to mean all signals except those\n\
9273 used by the debugger, typically SIGTRAP and SIGINT.\n\
9275 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9276 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9277 Stop means reenter debugger if this signal happens (implies print).\n\
9278 Print means print a message if this signal happens.\n\
9279 Pass means let program see this signal; otherwise program doesn't know.\n\
9280 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9281 Pass and Stop may be combined.\n\
9283 Multiple signals may be specified. Signal numbers and signal names\n\
9284 may be interspersed with actions, with the actions being performed for\n\
9285 all signals cumulatively specified."));
9286 set_cmd_completer (c, handle_completer);
9289 stop_command = add_cmd ("stop", class_obscure,
9290 not_just_help_class_command, _("\
9291 There is no `stop' command, but you can set a hook on `stop'.\n\
9292 This allows you to set a list of commands to be run each time execution\n\
9293 of the program stops."), &cmdlist);
9295 add_setshow_zuinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\
9296 Set inferior debugging."), _("\
9297 Show inferior debugging."), _("\
9298 When non-zero, inferior specific debugging is enabled."),
9301 &setdebuglist, &showdebuglist);
9303 add_setshow_boolean_cmd ("displaced", class_maintenance,
9304 &debug_displaced, _("\
9305 Set displaced stepping debugging."), _("\
9306 Show displaced stepping debugging."), _("\
9307 When non-zero, displaced stepping specific debugging is enabled."),
9309 show_debug_displaced,
9310 &setdebuglist, &showdebuglist);
9312 add_setshow_boolean_cmd ("non-stop", no_class,
9314 Set whether gdb controls the inferior in non-stop mode."), _("\
9315 Show whether gdb controls the inferior in non-stop mode."), _("\
9316 When debugging a multi-threaded program and this setting is\n\
9317 off (the default, also called all-stop mode), when one thread stops\n\
9318 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9319 all other threads in the program while you interact with the thread of\n\
9320 interest. When you continue or step a thread, you can allow the other\n\
9321 threads to run, or have them remain stopped, but while you inspect any\n\
9322 thread's state, all threads stop.\n\
9324 In non-stop mode, when one thread stops, other threads can continue\n\
9325 to run freely. You'll be able to step each thread independently,\n\
9326 leave it stopped or free to run as needed."),
9332 numsigs = (int) GDB_SIGNAL_LAST;
9333 signal_stop = XNEWVEC (unsigned char, numsigs);
9334 signal_print = XNEWVEC (unsigned char, numsigs);
9335 signal_program = XNEWVEC (unsigned char, numsigs);
9336 signal_catch = XNEWVEC (unsigned char, numsigs);
9337 signal_pass = XNEWVEC (unsigned char, numsigs);
9338 for (i = 0; i < numsigs; i++)
9341 signal_print[i] = 1;
9342 signal_program[i] = 1;
9343 signal_catch[i] = 0;
9346 /* Signals caused by debugger's own actions should not be given to
9347 the program afterwards.
9349 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9350 explicitly specifies that it should be delivered to the target
9351 program. Typically, that would occur when a user is debugging a
9352 target monitor on a simulator: the target monitor sets a
9353 breakpoint; the simulator encounters this breakpoint and halts
9354 the simulation handing control to GDB; GDB, noting that the stop
9355 address doesn't map to any known breakpoint, returns control back
9356 to the simulator; the simulator then delivers the hardware
9357 equivalent of a GDB_SIGNAL_TRAP to the program being
9359 signal_program[GDB_SIGNAL_TRAP] = 0;
9360 signal_program[GDB_SIGNAL_INT] = 0;
9362 /* Signals that are not errors should not normally enter the debugger. */
9363 signal_stop[GDB_SIGNAL_ALRM] = 0;
9364 signal_print[GDB_SIGNAL_ALRM] = 0;
9365 signal_stop[GDB_SIGNAL_VTALRM] = 0;
9366 signal_print[GDB_SIGNAL_VTALRM] = 0;
9367 signal_stop[GDB_SIGNAL_PROF] = 0;
9368 signal_print[GDB_SIGNAL_PROF] = 0;
9369 signal_stop[GDB_SIGNAL_CHLD] = 0;
9370 signal_print[GDB_SIGNAL_CHLD] = 0;
9371 signal_stop[GDB_SIGNAL_IO] = 0;
9372 signal_print[GDB_SIGNAL_IO] = 0;
9373 signal_stop[GDB_SIGNAL_POLL] = 0;
9374 signal_print[GDB_SIGNAL_POLL] = 0;
9375 signal_stop[GDB_SIGNAL_URG] = 0;
9376 signal_print[GDB_SIGNAL_URG] = 0;
9377 signal_stop[GDB_SIGNAL_WINCH] = 0;
9378 signal_print[GDB_SIGNAL_WINCH] = 0;
9379 signal_stop[GDB_SIGNAL_PRIO] = 0;
9380 signal_print[GDB_SIGNAL_PRIO] = 0;
9382 /* These signals are used internally by user-level thread
9383 implementations. (See signal(5) on Solaris.) Like the above
9384 signals, a healthy program receives and handles them as part of
9385 its normal operation. */
9386 signal_stop[GDB_SIGNAL_LWP] = 0;
9387 signal_print[GDB_SIGNAL_LWP] = 0;
9388 signal_stop[GDB_SIGNAL_WAITING] = 0;
9389 signal_print[GDB_SIGNAL_WAITING] = 0;
9390 signal_stop[GDB_SIGNAL_CANCEL] = 0;
9391 signal_print[GDB_SIGNAL_CANCEL] = 0;
9392 signal_stop[GDB_SIGNAL_LIBRT] = 0;
9393 signal_print[GDB_SIGNAL_LIBRT] = 0;
9395 /* Update cached state. */
9396 signal_cache_update (-1);
9398 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support,
9399 &stop_on_solib_events, _("\
9400 Set stopping for shared library events."), _("\
9401 Show stopping for shared library events."), _("\
9402 If nonzero, gdb will give control to the user when the dynamic linker\n\
9403 notifies gdb of shared library events. The most common event of interest\n\
9404 to the user would be loading/unloading of a new library."),
9405 set_stop_on_solib_events,
9406 show_stop_on_solib_events,
9407 &setlist, &showlist);
9409 add_setshow_enum_cmd ("follow-fork-mode", class_run,
9410 follow_fork_mode_kind_names,
9411 &follow_fork_mode_string, _("\
9412 Set debugger response to a program call of fork or vfork."), _("\
9413 Show debugger response to a program call of fork or vfork."), _("\
9414 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9415 parent - the original process is debugged after a fork\n\
9416 child - the new process is debugged after a fork\n\
9417 The unfollowed process will continue to run.\n\
9418 By default, the debugger will follow the parent process."),
9420 show_follow_fork_mode_string,
9421 &setlist, &showlist);
9423 add_setshow_enum_cmd ("follow-exec-mode", class_run,
9424 follow_exec_mode_names,
9425 &follow_exec_mode_string, _("\
9426 Set debugger response to a program call of exec."), _("\
9427 Show debugger response to a program call of exec."), _("\
9428 An exec call replaces the program image of a process.\n\
9430 follow-exec-mode can be:\n\
9432 new - the debugger creates a new inferior and rebinds the process\n\
9433 to this new inferior. The program the process was running before\n\
9434 the exec call can be restarted afterwards by restarting the original\n\
9437 same - the debugger keeps the process bound to the same inferior.\n\
9438 The new executable image replaces the previous executable loaded in\n\
9439 the inferior. Restarting the inferior after the exec call restarts\n\
9440 the executable the process was running after the exec call.\n\
9442 By default, the debugger will use the same inferior."),
9444 show_follow_exec_mode_string,
9445 &setlist, &showlist);
9447 add_setshow_enum_cmd ("scheduler-locking", class_run,
9448 scheduler_enums, &scheduler_mode, _("\
9449 Set mode for locking scheduler during execution."), _("\
9450 Show mode for locking scheduler during execution."), _("\
9451 off == no locking (threads may preempt at any time)\n\
9452 on == full locking (no thread except the current thread may run)\n\
9453 This applies to both normal execution and replay mode.\n\
9454 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9455 In this mode, other threads may run during other commands.\n\
9456 This applies to both normal execution and replay mode.\n\
9457 replay == scheduler locked in replay mode and unlocked during normal execution."),
9458 set_schedlock_func, /* traps on target vector */
9459 show_scheduler_mode,
9460 &setlist, &showlist);
9462 add_setshow_boolean_cmd ("schedule-multiple", class_run, &sched_multi, _("\
9463 Set mode for resuming threads of all processes."), _("\
9464 Show mode for resuming threads of all processes."), _("\
9465 When on, execution commands (such as 'continue' or 'next') resume all\n\
9466 threads of all processes. When off (which is the default), execution\n\
9467 commands only resume the threads of the current process. The set of\n\
9468 threads that are resumed is further refined by the scheduler-locking\n\
9469 mode (see help set scheduler-locking)."),
9471 show_schedule_multiple,
9472 &setlist, &showlist);
9474 add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\
9475 Set mode of the step operation."), _("\
9476 Show mode of the step operation."), _("\
9477 When set, doing a step over a function without debug line information\n\
9478 will stop at the first instruction of that function. Otherwise, the\n\
9479 function is skipped and the step command stops at a different source line."),
9481 show_step_stop_if_no_debug,
9482 &setlist, &showlist);
9484 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run,
9485 &can_use_displaced_stepping, _("\
9486 Set debugger's willingness to use displaced stepping."), _("\
9487 Show debugger's willingness to use displaced stepping."), _("\
9488 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9489 supported by the target architecture. If off, gdb will not use displaced\n\
9490 stepping to step over breakpoints, even if such is supported by the target\n\
9491 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9492 if the target architecture supports it and non-stop mode is active, but will not\n\
9493 use it in all-stop mode (see help set non-stop)."),
9495 show_can_use_displaced_stepping,
9496 &setlist, &showlist);
9498 add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names,
9499 &exec_direction, _("Set direction of execution.\n\
9500 Options are 'forward' or 'reverse'."),
9501 _("Show direction of execution (forward/reverse)."),
9502 _("Tells gdb whether to execute forward or backward."),
9503 set_exec_direction_func, show_exec_direction_func,
9504 &setlist, &showlist);
9506 /* Set/show detach-on-fork: user-settable mode. */
9508 add_setshow_boolean_cmd ("detach-on-fork", class_run, &detach_fork, _("\
9509 Set whether gdb will detach the child of a fork."), _("\
9510 Show whether gdb will detach the child of a fork."), _("\
9511 Tells gdb whether to detach the child of a fork."),
9512 NULL, NULL, &setlist, &showlist);
9514 /* Set/show disable address space randomization mode. */
9516 add_setshow_boolean_cmd ("disable-randomization", class_support,
9517 &disable_randomization, _("\
9518 Set disabling of debuggee's virtual address space randomization."), _("\
9519 Show disabling of debuggee's virtual address space randomization."), _("\
9520 When this mode is on (which is the default), randomization of the virtual\n\
9521 address space is disabled. Standalone programs run with the randomization\n\
9522 enabled by default on some platforms."),
9523 &set_disable_randomization,
9524 &show_disable_randomization,
9525 &setlist, &showlist);
9527 /* ptid initializations */
9528 inferior_ptid = null_ptid;
9529 target_last_wait_ptid = minus_one_ptid;
9531 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed);
9532 observer_attach_thread_stop_requested (infrun_thread_stop_requested);
9533 observer_attach_thread_exit (infrun_thread_thread_exit);
9534 observer_attach_inferior_exit (infrun_inferior_exit);
9536 /* Explicitly create without lookup, since that tries to create a
9537 value with a void typed value, and when we get here, gdbarch
9538 isn't initialized yet. At this point, we're quite sure there
9539 isn't another convenience variable of the same name. */
9540 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs, NULL);
9542 add_setshow_boolean_cmd ("observer", no_class,
9543 &observer_mode_1, _("\
9544 Set whether gdb controls the inferior in observer mode."), _("\
9545 Show whether gdb controls the inferior in observer mode."), _("\
9546 In observer mode, GDB can get data from the inferior, but not\n\
9547 affect its execution. Registers and memory may not be changed,\n\
9548 breakpoints may not be set, and the program cannot be interrupted\n\