1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2016 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 #include "event-loop.h"
65 #include "thread-fsm.h"
66 #include "common/enum-flags.h"
68 /* Prototypes for local functions */
70 static void signals_info (char *, int);
72 static void handle_command (char *, int);
74 static void sig_print_info (enum gdb_signal);
76 static void sig_print_header (void);
78 static void resume_cleanups (void *);
80 static int hook_stop_stub (void *);
82 static int restore_selected_frame (void *);
84 static int follow_fork (void);
86 static int follow_fork_inferior (int follow_child, int detach_fork);
88 static void follow_inferior_reset_breakpoints (void);
90 static void set_schedlock_func (char *args, int from_tty,
91 struct cmd_list_element *c);
93 static int currently_stepping (struct thread_info *tp);
95 void _initialize_infrun (void);
97 void nullify_last_target_wait_ptid (void);
99 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info *);
101 static void insert_step_resume_breakpoint_at_caller (struct frame_info *);
103 static void insert_longjmp_resume_breakpoint (struct gdbarch *, CORE_ADDR);
105 static int maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc);
107 /* Asynchronous signal handler registered as event loop source for
108 when we have pending events ready to be passed to the core. */
109 static struct async_event_handler *infrun_async_inferior_event_token;
111 /* Stores whether infrun_async was previously enabled or disabled.
112 Starts off as -1, indicating "never enabled/disabled". */
113 static int infrun_is_async = -1;
118 infrun_async (int enable)
120 if (infrun_is_async != enable)
122 infrun_is_async = enable;
125 fprintf_unfiltered (gdb_stdlog,
126 "infrun: infrun_async(%d)\n",
130 mark_async_event_handler (infrun_async_inferior_event_token);
132 clear_async_event_handler (infrun_async_inferior_event_token);
139 mark_infrun_async_event_handler (void)
141 mark_async_event_handler (infrun_async_inferior_event_token);
144 /* When set, stop the 'step' command if we enter a function which has
145 no line number information. The normal behavior is that we step
146 over such function. */
147 int step_stop_if_no_debug = 0;
149 show_step_stop_if_no_debug (struct ui_file *file, int from_tty,
150 struct cmd_list_element *c, const char *value)
152 fprintf_filtered (file, _("Mode of the step operation is %s.\n"), value);
155 /* proceed and normal_stop use this to notify the user when the
156 inferior stopped in a different thread than it had been running
159 static ptid_t previous_inferior_ptid;
161 /* If set (default for legacy reasons), when following a fork, GDB
162 will detach from one of the fork branches, child or parent.
163 Exactly which branch is detached depends on 'set follow-fork-mode'
166 static int detach_fork = 1;
168 int debug_displaced = 0;
170 show_debug_displaced (struct ui_file *file, int from_tty,
171 struct cmd_list_element *c, const char *value)
173 fprintf_filtered (file, _("Displace stepping debugging is %s.\n"), value);
176 unsigned int debug_infrun = 0;
178 show_debug_infrun (struct ui_file *file, int from_tty,
179 struct cmd_list_element *c, const char *value)
181 fprintf_filtered (file, _("Inferior debugging is %s.\n"), value);
185 /* Support for disabling address space randomization. */
187 int disable_randomization = 1;
190 show_disable_randomization (struct ui_file *file, int from_tty,
191 struct cmd_list_element *c, const char *value)
193 if (target_supports_disable_randomization ())
194 fprintf_filtered (file,
195 _("Disabling randomization of debuggee's "
196 "virtual address space is %s.\n"),
199 fputs_filtered (_("Disabling randomization of debuggee's "
200 "virtual address space is unsupported on\n"
201 "this platform.\n"), file);
205 set_disable_randomization (char *args, int from_tty,
206 struct cmd_list_element *c)
208 if (!target_supports_disable_randomization ())
209 error (_("Disabling randomization of debuggee's "
210 "virtual address space is unsupported on\n"
214 /* User interface for non-stop mode. */
217 static int non_stop_1 = 0;
220 set_non_stop (char *args, int from_tty,
221 struct cmd_list_element *c)
223 if (target_has_execution)
225 non_stop_1 = non_stop;
226 error (_("Cannot change this setting while the inferior is running."));
229 non_stop = non_stop_1;
233 show_non_stop (struct ui_file *file, int from_tty,
234 struct cmd_list_element *c, const char *value)
236 fprintf_filtered (file,
237 _("Controlling the inferior in non-stop mode is %s.\n"),
241 /* "Observer mode" is somewhat like a more extreme version of
242 non-stop, in which all GDB operations that might affect the
243 target's execution have been disabled. */
245 int observer_mode = 0;
246 static int observer_mode_1 = 0;
249 set_observer_mode (char *args, int from_tty,
250 struct cmd_list_element *c)
252 if (target_has_execution)
254 observer_mode_1 = observer_mode;
255 error (_("Cannot change this setting while the inferior is running."));
258 observer_mode = observer_mode_1;
260 may_write_registers = !observer_mode;
261 may_write_memory = !observer_mode;
262 may_insert_breakpoints = !observer_mode;
263 may_insert_tracepoints = !observer_mode;
264 /* We can insert fast tracepoints in or out of observer mode,
265 but enable them if we're going into this mode. */
267 may_insert_fast_tracepoints = 1;
268 may_stop = !observer_mode;
269 update_target_permissions ();
271 /* Going *into* observer mode we must force non-stop, then
272 going out we leave it that way. */
275 pagination_enabled = 0;
276 non_stop = non_stop_1 = 1;
280 printf_filtered (_("Observer mode is now %s.\n"),
281 (observer_mode ? "on" : "off"));
285 show_observer_mode (struct ui_file *file, int from_tty,
286 struct cmd_list_element *c, const char *value)
288 fprintf_filtered (file, _("Observer mode is %s.\n"), value);
291 /* This updates the value of observer mode based on changes in
292 permissions. Note that we are deliberately ignoring the values of
293 may-write-registers and may-write-memory, since the user may have
294 reason to enable these during a session, for instance to turn on a
295 debugging-related global. */
298 update_observer_mode (void)
302 newval = (!may_insert_breakpoints
303 && !may_insert_tracepoints
304 && may_insert_fast_tracepoints
308 /* Let the user know if things change. */
309 if (newval != observer_mode)
310 printf_filtered (_("Observer mode is now %s.\n"),
311 (newval ? "on" : "off"));
313 observer_mode = observer_mode_1 = newval;
316 /* Tables of how to react to signals; the user sets them. */
318 static unsigned char *signal_stop;
319 static unsigned char *signal_print;
320 static unsigned char *signal_program;
322 /* Table of signals that are registered with "catch signal". A
323 non-zero entry indicates that the signal is caught by some "catch
324 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
326 static unsigned char *signal_catch;
328 /* Table of signals that the target may silently handle.
329 This is automatically determined from the flags above,
330 and simply cached here. */
331 static unsigned char *signal_pass;
333 #define SET_SIGS(nsigs,sigs,flags) \
335 int signum = (nsigs); \
336 while (signum-- > 0) \
337 if ((sigs)[signum]) \
338 (flags)[signum] = 1; \
341 #define UNSET_SIGS(nsigs,sigs,flags) \
343 int signum = (nsigs); \
344 while (signum-- > 0) \
345 if ((sigs)[signum]) \
346 (flags)[signum] = 0; \
349 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
350 this function is to avoid exporting `signal_program'. */
353 update_signals_program_target (void)
355 target_program_signals ((int) GDB_SIGNAL_LAST, signal_program);
358 /* Value to pass to target_resume() to cause all threads to resume. */
360 #define RESUME_ALL minus_one_ptid
362 /* Command list pointer for the "stop" placeholder. */
364 static struct cmd_list_element *stop_command;
366 /* Nonzero if we want to give control to the user when we're notified
367 of shared library events by the dynamic linker. */
368 int stop_on_solib_events;
370 /* Enable or disable optional shared library event breakpoints
371 as appropriate when the above flag is changed. */
374 set_stop_on_solib_events (char *args, int from_tty, struct cmd_list_element *c)
376 update_solib_breakpoints ();
380 show_stop_on_solib_events (struct ui_file *file, int from_tty,
381 struct cmd_list_element *c, const char *value)
383 fprintf_filtered (file, _("Stopping for shared library events is %s.\n"),
387 /* Nonzero after stop if current stack frame should be printed. */
389 static int stop_print_frame;
391 /* This is a cached copy of the pid/waitstatus of the last event
392 returned by target_wait()/deprecated_target_wait_hook(). This
393 information is returned by get_last_target_status(). */
394 static ptid_t target_last_wait_ptid;
395 static struct target_waitstatus target_last_waitstatus;
397 static void context_switch (ptid_t ptid);
399 void init_thread_stepping_state (struct thread_info *tss);
401 static const char follow_fork_mode_child[] = "child";
402 static const char follow_fork_mode_parent[] = "parent";
404 static const char *const follow_fork_mode_kind_names[] = {
405 follow_fork_mode_child,
406 follow_fork_mode_parent,
410 static const char *follow_fork_mode_string = follow_fork_mode_parent;
412 show_follow_fork_mode_string (struct ui_file *file, int from_tty,
413 struct cmd_list_element *c, const char *value)
415 fprintf_filtered (file,
416 _("Debugger response to a program "
417 "call of fork or vfork is \"%s\".\n"),
422 /* Handle changes to the inferior list based on the type of fork,
423 which process is being followed, and whether the other process
424 should be detached. On entry inferior_ptid must be the ptid of
425 the fork parent. At return inferior_ptid is the ptid of the
426 followed inferior. */
429 follow_fork_inferior (int follow_child, int detach_fork)
432 ptid_t parent_ptid, child_ptid;
434 has_vforked = (inferior_thread ()->pending_follow.kind
435 == TARGET_WAITKIND_VFORKED);
436 parent_ptid = inferior_ptid;
437 child_ptid = inferior_thread ()->pending_follow.value.related_pid;
440 && !non_stop /* Non-stop always resumes both branches. */
441 && current_ui->prompt_state == PROMPT_BLOCKED
442 && !(follow_child || detach_fork || sched_multi))
444 /* The parent stays blocked inside the vfork syscall until the
445 child execs or exits. If we don't let the child run, then
446 the parent stays blocked. If we're telling the parent to run
447 in the foreground, the user will not be able to ctrl-c to get
448 back the terminal, effectively hanging the debug session. */
449 fprintf_filtered (gdb_stderr, _("\
450 Can not resume the parent process over vfork in the foreground while\n\
451 holding the child stopped. Try \"set detach-on-fork\" or \
452 \"set schedule-multiple\".\n"));
453 /* FIXME output string > 80 columns. */
459 /* Detach new forked process? */
462 /* Before detaching from the child, remove all breakpoints
463 from it. If we forked, then this has already been taken
464 care of by infrun.c. If we vforked however, any
465 breakpoint inserted in the parent is visible in the
466 child, even those added while stopped in a vfork
467 catchpoint. This will remove the breakpoints from the
468 parent also, but they'll be reinserted below. */
471 /* Keep breakpoints list in sync. */
472 remove_breakpoints_pid (ptid_get_pid (inferior_ptid));
475 if (info_verbose || debug_infrun)
477 /* Ensure that we have a process ptid. */
478 ptid_t process_ptid = pid_to_ptid (ptid_get_pid (child_ptid));
480 target_terminal_ours_for_output ();
481 fprintf_filtered (gdb_stdlog,
482 _("Detaching after %s from child %s.\n"),
483 has_vforked ? "vfork" : "fork",
484 target_pid_to_str (process_ptid));
489 struct inferior *parent_inf, *child_inf;
490 struct cleanup *old_chain;
492 /* Add process to GDB's tables. */
493 child_inf = add_inferior (ptid_get_pid (child_ptid));
495 parent_inf = current_inferior ();
496 child_inf->attach_flag = parent_inf->attach_flag;
497 copy_terminal_info (child_inf, parent_inf);
498 child_inf->gdbarch = parent_inf->gdbarch;
499 copy_inferior_target_desc_info (child_inf, parent_inf);
501 old_chain = save_inferior_ptid ();
502 save_current_program_space ();
504 inferior_ptid = child_ptid;
505 add_thread (inferior_ptid);
506 child_inf->symfile_flags = SYMFILE_NO_READ;
508 /* If this is a vfork child, then the address-space is
509 shared with the parent. */
512 child_inf->pspace = parent_inf->pspace;
513 child_inf->aspace = parent_inf->aspace;
515 /* The parent will be frozen until the child is done
516 with the shared region. Keep track of the
518 child_inf->vfork_parent = parent_inf;
519 child_inf->pending_detach = 0;
520 parent_inf->vfork_child = child_inf;
521 parent_inf->pending_detach = 0;
525 child_inf->aspace = new_address_space ();
526 child_inf->pspace = add_program_space (child_inf->aspace);
527 child_inf->removable = 1;
528 set_current_program_space (child_inf->pspace);
529 clone_program_space (child_inf->pspace, parent_inf->pspace);
531 /* Let the shared library layer (e.g., solib-svr4) learn
532 about this new process, relocate the cloned exec, pull
533 in shared libraries, and install the solib event
534 breakpoint. If a "cloned-VM" event was propagated
535 better throughout the core, this wouldn't be
537 solib_create_inferior_hook (0);
540 do_cleanups (old_chain);
545 struct inferior *parent_inf;
547 parent_inf = current_inferior ();
549 /* If we detached from the child, then we have to be careful
550 to not insert breakpoints in the parent until the child
551 is done with the shared memory region. However, if we're
552 staying attached to the child, then we can and should
553 insert breakpoints, so that we can debug it. A
554 subsequent child exec or exit is enough to know when does
555 the child stops using the parent's address space. */
556 parent_inf->waiting_for_vfork_done = detach_fork;
557 parent_inf->pspace->breakpoints_not_allowed = detach_fork;
562 /* Follow the child. */
563 struct inferior *parent_inf, *child_inf;
564 struct program_space *parent_pspace;
566 if (info_verbose || debug_infrun)
568 target_terminal_ours_for_output ();
569 fprintf_filtered (gdb_stdlog,
570 _("Attaching after %s %s to child %s.\n"),
571 target_pid_to_str (parent_ptid),
572 has_vforked ? "vfork" : "fork",
573 target_pid_to_str (child_ptid));
576 /* Add the new inferior first, so that the target_detach below
577 doesn't unpush the target. */
579 child_inf = add_inferior (ptid_get_pid (child_ptid));
581 parent_inf = current_inferior ();
582 child_inf->attach_flag = parent_inf->attach_flag;
583 copy_terminal_info (child_inf, parent_inf);
584 child_inf->gdbarch = parent_inf->gdbarch;
585 copy_inferior_target_desc_info (child_inf, parent_inf);
587 parent_pspace = parent_inf->pspace;
589 /* If we're vforking, we want to hold on to the parent until the
590 child exits or execs. At child exec or exit time we can
591 remove the old breakpoints from the parent and detach or
592 resume debugging it. Otherwise, detach the parent now; we'll
593 want to reuse it's program/address spaces, but we can't set
594 them to the child before removing breakpoints from the
595 parent, otherwise, the breakpoints module could decide to
596 remove breakpoints from the wrong process (since they'd be
597 assigned to the same address space). */
601 gdb_assert (child_inf->vfork_parent == NULL);
602 gdb_assert (parent_inf->vfork_child == NULL);
603 child_inf->vfork_parent = parent_inf;
604 child_inf->pending_detach = 0;
605 parent_inf->vfork_child = child_inf;
606 parent_inf->pending_detach = detach_fork;
607 parent_inf->waiting_for_vfork_done = 0;
609 else if (detach_fork)
611 if (info_verbose || debug_infrun)
613 /* Ensure that we have a process ptid. */
614 ptid_t process_ptid = pid_to_ptid (ptid_get_pid (child_ptid));
616 target_terminal_ours_for_output ();
617 fprintf_filtered (gdb_stdlog,
618 _("Detaching after fork from "
620 target_pid_to_str (process_ptid));
623 target_detach (NULL, 0);
626 /* Note that the detach above makes PARENT_INF dangling. */
628 /* Add the child thread to the appropriate lists, and switch to
629 this new thread, before cloning the program space, and
630 informing the solib layer about this new process. */
632 inferior_ptid = child_ptid;
633 add_thread (inferior_ptid);
635 /* If this is a vfork child, then the address-space is shared
636 with the parent. If we detached from the parent, then we can
637 reuse the parent's program/address spaces. */
638 if (has_vforked || detach_fork)
640 child_inf->pspace = parent_pspace;
641 child_inf->aspace = child_inf->pspace->aspace;
645 child_inf->aspace = new_address_space ();
646 child_inf->pspace = add_program_space (child_inf->aspace);
647 child_inf->removable = 1;
648 child_inf->symfile_flags = SYMFILE_NO_READ;
649 set_current_program_space (child_inf->pspace);
650 clone_program_space (child_inf->pspace, parent_pspace);
652 /* Let the shared library layer (e.g., solib-svr4) learn
653 about this new process, relocate the cloned exec, pull in
654 shared libraries, and install the solib event breakpoint.
655 If a "cloned-VM" event was propagated better throughout
656 the core, this wouldn't be required. */
657 solib_create_inferior_hook (0);
661 return target_follow_fork (follow_child, detach_fork);
664 /* Tell the target to follow the fork we're stopped at. Returns true
665 if the inferior should be resumed; false, if the target for some
666 reason decided it's best not to resume. */
671 int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
672 int should_resume = 1;
673 struct thread_info *tp;
675 /* Copy user stepping state to the new inferior thread. FIXME: the
676 followed fork child thread should have a copy of most of the
677 parent thread structure's run control related fields, not just these.
678 Initialized to avoid "may be used uninitialized" warnings from gcc. */
679 struct breakpoint *step_resume_breakpoint = NULL;
680 struct breakpoint *exception_resume_breakpoint = NULL;
681 CORE_ADDR step_range_start = 0;
682 CORE_ADDR step_range_end = 0;
683 struct frame_id step_frame_id = { 0 };
684 struct 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 /* Called whenever we notice an exec or exit event, to handle
898 detaching or resuming a vfork parent. */
901 handle_vfork_child_exec_or_exit (int exec)
903 struct inferior *inf = current_inferior ();
905 if (inf->vfork_parent)
907 int resume_parent = -1;
909 /* This exec or exit marks the end of the shared memory region
910 between the parent and the child. If the user wanted to
911 detach from the parent, now is the time. */
913 if (inf->vfork_parent->pending_detach)
915 struct thread_info *tp;
916 struct cleanup *old_chain;
917 struct program_space *pspace;
918 struct address_space *aspace;
920 /* follow-fork child, detach-on-fork on. */
922 inf->vfork_parent->pending_detach = 0;
926 /* If we're handling a child exit, then inferior_ptid
927 points at the inferior's pid, not to a thread. */
928 old_chain = save_inferior_ptid ();
929 save_current_program_space ();
930 save_current_inferior ();
933 old_chain = save_current_space_and_thread ();
935 /* We're letting loose of the parent. */
936 tp = any_live_thread_of_process (inf->vfork_parent->pid);
937 switch_to_thread (tp->ptid);
939 /* We're about to detach from the parent, which implicitly
940 removes breakpoints from its address space. There's a
941 catch here: we want to reuse the spaces for the child,
942 but, parent/child are still sharing the pspace at this
943 point, although the exec in reality makes the kernel give
944 the child a fresh set of new pages. The problem here is
945 that the breakpoints module being unaware of this, would
946 likely chose the child process to write to the parent
947 address space. Swapping the child temporarily away from
948 the spaces has the desired effect. Yes, this is "sort
951 pspace = inf->pspace;
952 aspace = inf->aspace;
956 if (debug_infrun || info_verbose)
958 target_terminal_ours_for_output ();
962 fprintf_filtered (gdb_stdlog,
963 _("Detaching vfork parent process "
964 "%d after child exec.\n"),
965 inf->vfork_parent->pid);
969 fprintf_filtered (gdb_stdlog,
970 _("Detaching vfork parent process "
971 "%d after child exit.\n"),
972 inf->vfork_parent->pid);
976 target_detach (NULL, 0);
979 inf->pspace = pspace;
980 inf->aspace = aspace;
982 do_cleanups (old_chain);
986 /* We're staying attached to the parent, so, really give the
987 child a new address space. */
988 inf->pspace = add_program_space (maybe_new_address_space ());
989 inf->aspace = inf->pspace->aspace;
991 set_current_program_space (inf->pspace);
993 resume_parent = inf->vfork_parent->pid;
995 /* Break the bonds. */
996 inf->vfork_parent->vfork_child = NULL;
1000 struct cleanup *old_chain;
1001 struct program_space *pspace;
1003 /* If this is a vfork child exiting, then the pspace and
1004 aspaces were shared with the parent. Since we're
1005 reporting the process exit, we'll be mourning all that is
1006 found in the address space, and switching to null_ptid,
1007 preparing to start a new inferior. But, since we don't
1008 want to clobber the parent's address/program spaces, we
1009 go ahead and create a new one for this exiting
1012 /* Switch to null_ptid, so that clone_program_space doesn't want
1013 to read the selected frame of a dead process. */
1014 old_chain = save_inferior_ptid ();
1015 inferior_ptid = null_ptid;
1017 /* This inferior is dead, so avoid giving the breakpoints
1018 module the option to write through to it (cloning a
1019 program space resets breakpoints). */
1022 pspace = add_program_space (maybe_new_address_space ());
1023 set_current_program_space (pspace);
1025 inf->symfile_flags = SYMFILE_NO_READ;
1026 clone_program_space (pspace, inf->vfork_parent->pspace);
1027 inf->pspace = pspace;
1028 inf->aspace = pspace->aspace;
1030 /* Put back inferior_ptid. We'll continue mourning this
1032 do_cleanups (old_chain);
1034 resume_parent = inf->vfork_parent->pid;
1035 /* Break the bonds. */
1036 inf->vfork_parent->vfork_child = NULL;
1039 inf->vfork_parent = NULL;
1041 gdb_assert (current_program_space == inf->pspace);
1043 if (non_stop && resume_parent != -1)
1045 /* If the user wanted the parent to be running, let it go
1047 struct cleanup *old_chain = make_cleanup_restore_current_thread ();
1050 fprintf_unfiltered (gdb_stdlog,
1051 "infrun: resuming vfork parent process %d\n",
1054 iterate_over_threads (proceed_after_vfork_done, &resume_parent);
1056 do_cleanups (old_chain);
1061 /* Enum strings for "set|show follow-exec-mode". */
1063 static const char follow_exec_mode_new[] = "new";
1064 static const char follow_exec_mode_same[] = "same";
1065 static const char *const follow_exec_mode_names[] =
1067 follow_exec_mode_new,
1068 follow_exec_mode_same,
1072 static const char *follow_exec_mode_string = follow_exec_mode_same;
1074 show_follow_exec_mode_string (struct ui_file *file, int from_tty,
1075 struct cmd_list_element *c, const char *value)
1077 fprintf_filtered (file, _("Follow exec mode is \"%s\".\n"), value);
1080 /* EXECD_PATHNAME is assumed to be non-NULL. */
1083 follow_exec (ptid_t ptid, char *execd_pathname)
1085 struct thread_info *th, *tmp;
1086 struct inferior *inf = current_inferior ();
1087 int pid = ptid_get_pid (ptid);
1088 ptid_t process_ptid;
1090 /* This is an exec event that we actually wish to pay attention to.
1091 Refresh our symbol table to the newly exec'd program, remove any
1092 momentary bp's, etc.
1094 If there are breakpoints, they aren't really inserted now,
1095 since the exec() transformed our inferior into a fresh set
1098 We want to preserve symbolic breakpoints on the list, since
1099 we have hopes that they can be reset after the new a.out's
1100 symbol table is read.
1102 However, any "raw" breakpoints must be removed from the list
1103 (e.g., the solib bp's), since their address is probably invalid
1106 And, we DON'T want to call delete_breakpoints() here, since
1107 that may write the bp's "shadow contents" (the instruction
1108 value that was overwritten witha TRAP instruction). Since
1109 we now have a new a.out, those shadow contents aren't valid. */
1111 mark_breakpoints_out ();
1113 /* The target reports the exec event to the main thread, even if
1114 some other thread does the exec, and even if the main thread was
1115 stopped or already gone. We may still have non-leader threads of
1116 the process on our list. E.g., on targets that don't have thread
1117 exit events (like remote); or on native Linux in non-stop mode if
1118 there were only two threads in the inferior and the non-leader
1119 one is the one that execs (and nothing forces an update of the
1120 thread list up to here). When debugging remotely, it's best to
1121 avoid extra traffic, when possible, so avoid syncing the thread
1122 list with the target, and instead go ahead and delete all threads
1123 of the process but one that reported the event. Note this must
1124 be done before calling update_breakpoints_after_exec, as
1125 otherwise clearing the threads' resources would reference stale
1126 thread breakpoints -- it may have been one of these threads that
1127 stepped across the exec. We could just clear their stepping
1128 states, but as long as we're iterating, might as well delete
1129 them. Deleting them now rather than at the next user-visible
1130 stop provides a nicer sequence of events for user and MI
1132 ALL_THREADS_SAFE (th, tmp)
1133 if (ptid_get_pid (th->ptid) == pid && !ptid_equal (th->ptid, ptid))
1134 delete_thread (th->ptid);
1136 /* We also need to clear any left over stale state for the
1137 leader/event thread. E.g., if there was any step-resume
1138 breakpoint or similar, it's gone now. We cannot truly
1139 step-to-next statement through an exec(). */
1140 th = inferior_thread ();
1141 th->control.step_resume_breakpoint = NULL;
1142 th->control.exception_resume_breakpoint = NULL;
1143 th->control.single_step_breakpoints = NULL;
1144 th->control.step_range_start = 0;
1145 th->control.step_range_end = 0;
1147 /* The user may have had the main thread held stopped in the
1148 previous image (e.g., schedlock on, or non-stop). Release
1150 th->stop_requested = 0;
1152 update_breakpoints_after_exec ();
1154 /* What is this a.out's name? */
1155 process_ptid = pid_to_ptid (pid);
1156 printf_unfiltered (_("%s is executing new program: %s\n"),
1157 target_pid_to_str (process_ptid),
1160 /* We've followed the inferior through an exec. Therefore, the
1161 inferior has essentially been killed & reborn. */
1163 gdb_flush (gdb_stdout);
1165 breakpoint_init_inferior (inf_execd);
1167 if (*gdb_sysroot != '\0')
1169 char *name = exec_file_find (execd_pathname, NULL);
1171 execd_pathname = (char *) alloca (strlen (name) + 1);
1172 strcpy (execd_pathname, name);
1176 /* Reset the shared library package. This ensures that we get a
1177 shlib event when the child reaches "_start", at which point the
1178 dld will have had a chance to initialize the child. */
1179 /* Also, loading a symbol file below may trigger symbol lookups, and
1180 we don't want those to be satisfied by the libraries of the
1181 previous incarnation of this process. */
1182 no_shared_libraries (NULL, 0);
1184 if (follow_exec_mode_string == follow_exec_mode_new)
1186 /* The user wants to keep the old inferior and program spaces
1187 around. Create a new fresh one, and switch to it. */
1189 /* Do exit processing for the original inferior before adding
1190 the new inferior so we don't have two active inferiors with
1191 the same ptid, which can confuse find_inferior_ptid. */
1192 exit_inferior_num_silent (current_inferior ()->num);
1194 inf = add_inferior_with_spaces ();
1196 target_follow_exec (inf, execd_pathname);
1198 set_current_inferior (inf);
1199 set_current_program_space (inf->pspace);
1204 /* The old description may no longer be fit for the new image.
1205 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1206 old description; we'll read a new one below. No need to do
1207 this on "follow-exec-mode new", as the old inferior stays
1208 around (its description is later cleared/refetched on
1210 target_clear_description ();
1213 gdb_assert (current_program_space == inf->pspace);
1215 /* That a.out is now the one to use. */
1216 exec_file_attach (execd_pathname, 0);
1218 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1219 (Position Independent Executable) main symbol file will get applied by
1220 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1221 the breakpoints with the zero displacement. */
1223 symbol_file_add (execd_pathname,
1225 | SYMFILE_MAINLINE | SYMFILE_DEFER_BP_RESET),
1228 if ((inf->symfile_flags & SYMFILE_NO_READ) == 0)
1229 set_initial_language ();
1231 /* If the target can specify a description, read it. Must do this
1232 after flipping to the new executable (because the target supplied
1233 description must be compatible with the executable's
1234 architecture, and the old executable may e.g., be 32-bit, while
1235 the new one 64-bit), and before anything involving memory or
1237 target_find_description ();
1239 solib_create_inferior_hook (0);
1241 jit_inferior_created_hook ();
1243 breakpoint_re_set ();
1245 /* Reinsert all breakpoints. (Those which were symbolic have
1246 been reset to the proper address in the new a.out, thanks
1247 to symbol_file_command...). */
1248 insert_breakpoints ();
1250 /* The next resume of this inferior should bring it to the shlib
1251 startup breakpoints. (If the user had also set bp's on
1252 "main" from the old (parent) process, then they'll auto-
1253 matically get reset there in the new process.). */
1256 /* The queue of threads that need to do a step-over operation to get
1257 past e.g., a breakpoint. What technique is used to step over the
1258 breakpoint/watchpoint does not matter -- all threads end up in the
1259 same queue, to maintain rough temporal order of execution, in order
1260 to avoid starvation, otherwise, we could e.g., find ourselves
1261 constantly stepping the same couple threads past their breakpoints
1262 over and over, if the single-step finish fast enough. */
1263 struct thread_info *step_over_queue_head;
1265 /* Bit flags indicating what the thread needs to step over. */
1267 enum step_over_what_flag
1269 /* Step over a breakpoint. */
1270 STEP_OVER_BREAKPOINT = 1,
1272 /* Step past a non-continuable watchpoint, in order to let the
1273 instruction execute so we can evaluate the watchpoint
1275 STEP_OVER_WATCHPOINT = 2
1277 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag, step_over_what);
1279 /* Info about an instruction that is being stepped over. */
1281 struct step_over_info
1283 /* If we're stepping past a breakpoint, this is the address space
1284 and address of the instruction the breakpoint is set at. We'll
1285 skip inserting all breakpoints here. Valid iff ASPACE is
1287 struct address_space *aspace;
1290 /* The instruction being stepped over triggers a nonsteppable
1291 watchpoint. If true, we'll skip inserting watchpoints. */
1292 int nonsteppable_watchpoint_p;
1294 /* The thread's global number. */
1298 /* The step-over info of the location that is being stepped over.
1300 Note that with async/breakpoint always-inserted mode, a user might
1301 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1302 being stepped over. As setting a new breakpoint inserts all
1303 breakpoints, we need to make sure the breakpoint being stepped over
1304 isn't inserted then. We do that by only clearing the step-over
1305 info when the step-over is actually finished (or aborted).
1307 Presently GDB can only step over one breakpoint at any given time.
1308 Given threads that can't run code in the same address space as the
1309 breakpoint's can't really miss the breakpoint, GDB could be taught
1310 to step-over at most one breakpoint per address space (so this info
1311 could move to the address space object if/when GDB is extended).
1312 The set of breakpoints being stepped over will normally be much
1313 smaller than the set of all breakpoints, so a flag in the
1314 breakpoint location structure would be wasteful. A separate list
1315 also saves complexity and run-time, as otherwise we'd have to go
1316 through all breakpoint locations clearing their flag whenever we
1317 start a new sequence. Similar considerations weigh against storing
1318 this info in the thread object. Plus, not all step overs actually
1319 have breakpoint locations -- e.g., stepping past a single-step
1320 breakpoint, or stepping to complete a non-continuable
1322 static struct step_over_info step_over_info;
1324 /* Record the address of the breakpoint/instruction we're currently
1328 set_step_over_info (struct address_space *aspace, CORE_ADDR address,
1329 int nonsteppable_watchpoint_p,
1332 step_over_info.aspace = aspace;
1333 step_over_info.address = address;
1334 step_over_info.nonsteppable_watchpoint_p = nonsteppable_watchpoint_p;
1335 step_over_info.thread = thread;
1338 /* Called when we're not longer stepping over a breakpoint / an
1339 instruction, so all breakpoints are free to be (re)inserted. */
1342 clear_step_over_info (void)
1345 fprintf_unfiltered (gdb_stdlog,
1346 "infrun: clear_step_over_info\n");
1347 step_over_info.aspace = NULL;
1348 step_over_info.address = 0;
1349 step_over_info.nonsteppable_watchpoint_p = 0;
1350 step_over_info.thread = -1;
1356 stepping_past_instruction_at (struct address_space *aspace,
1359 return (step_over_info.aspace != NULL
1360 && breakpoint_address_match (aspace, address,
1361 step_over_info.aspace,
1362 step_over_info.address));
1368 thread_is_stepping_over_breakpoint (int thread)
1370 return (step_over_info.thread != -1
1371 && thread == step_over_info.thread);
1377 stepping_past_nonsteppable_watchpoint (void)
1379 return step_over_info.nonsteppable_watchpoint_p;
1382 /* Returns true if step-over info is valid. */
1385 step_over_info_valid_p (void)
1387 return (step_over_info.aspace != NULL
1388 || stepping_past_nonsteppable_watchpoint ());
1392 /* Displaced stepping. */
1394 /* In non-stop debugging mode, we must take special care to manage
1395 breakpoints properly; in particular, the traditional strategy for
1396 stepping a thread past a breakpoint it has hit is unsuitable.
1397 'Displaced stepping' is a tactic for stepping one thread past a
1398 breakpoint it has hit while ensuring that other threads running
1399 concurrently will hit the breakpoint as they should.
1401 The traditional way to step a thread T off a breakpoint in a
1402 multi-threaded program in all-stop mode is as follows:
1404 a0) Initially, all threads are stopped, and breakpoints are not
1406 a1) We single-step T, leaving breakpoints uninserted.
1407 a2) We insert breakpoints, and resume all threads.
1409 In non-stop debugging, however, this strategy is unsuitable: we
1410 don't want to have to stop all threads in the system in order to
1411 continue or step T past a breakpoint. Instead, we use displaced
1414 n0) Initially, T is stopped, other threads are running, and
1415 breakpoints are inserted.
1416 n1) We copy the instruction "under" the breakpoint to a separate
1417 location, outside the main code stream, making any adjustments
1418 to the instruction, register, and memory state as directed by
1420 n2) We single-step T over the instruction at its new location.
1421 n3) We adjust the resulting register and memory state as directed
1422 by T's architecture. This includes resetting T's PC to point
1423 back into the main instruction stream.
1426 This approach depends on the following gdbarch methods:
1428 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1429 indicate where to copy the instruction, and how much space must
1430 be reserved there. We use these in step n1.
1432 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1433 address, and makes any necessary adjustments to the instruction,
1434 register contents, and memory. We use this in step n1.
1436 - gdbarch_displaced_step_fixup adjusts registers and memory after
1437 we have successfuly single-stepped the instruction, to yield the
1438 same effect the instruction would have had if we had executed it
1439 at its original address. We use this in step n3.
1441 - gdbarch_displaced_step_free_closure provides cleanup.
1443 The gdbarch_displaced_step_copy_insn and
1444 gdbarch_displaced_step_fixup functions must be written so that
1445 copying an instruction with gdbarch_displaced_step_copy_insn,
1446 single-stepping across the copied instruction, and then applying
1447 gdbarch_displaced_insn_fixup should have the same effects on the
1448 thread's memory and registers as stepping the instruction in place
1449 would have. Exactly which responsibilities fall to the copy and
1450 which fall to the fixup is up to the author of those functions.
1452 See the comments in gdbarch.sh for details.
1454 Note that displaced stepping and software single-step cannot
1455 currently be used in combination, although with some care I think
1456 they could be made to. Software single-step works by placing
1457 breakpoints on all possible subsequent instructions; if the
1458 displaced instruction is a PC-relative jump, those breakpoints
1459 could fall in very strange places --- on pages that aren't
1460 executable, or at addresses that are not proper instruction
1461 boundaries. (We do generally let other threads run while we wait
1462 to hit the software single-step breakpoint, and they might
1463 encounter such a corrupted instruction.) One way to work around
1464 this would be to have gdbarch_displaced_step_copy_insn fully
1465 simulate the effect of PC-relative instructions (and return NULL)
1466 on architectures that use software single-stepping.
1468 In non-stop mode, we can have independent and simultaneous step
1469 requests, so more than one thread may need to simultaneously step
1470 over a breakpoint. The current implementation assumes there is
1471 only one scratch space per process. In this case, we have to
1472 serialize access to the scratch space. If thread A wants to step
1473 over a breakpoint, but we are currently waiting for some other
1474 thread to complete a displaced step, we leave thread A stopped and
1475 place it in the displaced_step_request_queue. Whenever a displaced
1476 step finishes, we pick the next thread in the queue and start a new
1477 displaced step operation on it. See displaced_step_prepare and
1478 displaced_step_fixup for details. */
1480 /* Per-inferior displaced stepping state. */
1481 struct displaced_step_inferior_state
1483 /* Pointer to next in linked list. */
1484 struct displaced_step_inferior_state *next;
1486 /* The process this displaced step state refers to. */
1489 /* True if preparing a displaced step ever failed. If so, we won't
1490 try displaced stepping for this inferior again. */
1493 /* If this is not null_ptid, this is the thread carrying out a
1494 displaced single-step in process PID. This thread's state will
1495 require fixing up once it has completed its step. */
1498 /* The architecture the thread had when we stepped it. */
1499 struct gdbarch *step_gdbarch;
1501 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1502 for post-step cleanup. */
1503 struct displaced_step_closure *step_closure;
1505 /* The address of the original instruction, and the copy we
1507 CORE_ADDR step_original, step_copy;
1509 /* Saved contents of copy area. */
1510 gdb_byte *step_saved_copy;
1513 /* The list of states of processes involved in displaced stepping
1515 static struct displaced_step_inferior_state *displaced_step_inferior_states;
1517 /* Get the displaced stepping state of process PID. */
1519 static struct displaced_step_inferior_state *
1520 get_displaced_stepping_state (int pid)
1522 struct displaced_step_inferior_state *state;
1524 for (state = displaced_step_inferior_states;
1526 state = state->next)
1527 if (state->pid == pid)
1533 /* Returns true if any inferior has a thread doing a displaced
1537 displaced_step_in_progress_any_inferior (void)
1539 struct displaced_step_inferior_state *state;
1541 for (state = displaced_step_inferior_states;
1543 state = state->next)
1544 if (!ptid_equal (state->step_ptid, null_ptid))
1550 /* Return true if thread represented by PTID is doing a displaced
1554 displaced_step_in_progress_thread (ptid_t ptid)
1556 struct displaced_step_inferior_state *displaced;
1558 gdb_assert (!ptid_equal (ptid, null_ptid));
1560 displaced = get_displaced_stepping_state (ptid_get_pid (ptid));
1562 return (displaced != NULL && ptid_equal (displaced->step_ptid, ptid));
1565 /* Return true if process PID has a thread doing a displaced step. */
1568 displaced_step_in_progress (int pid)
1570 struct displaced_step_inferior_state *displaced;
1572 displaced = get_displaced_stepping_state (pid);
1573 if (displaced != NULL && !ptid_equal (displaced->step_ptid, null_ptid))
1579 /* Add a new displaced stepping state for process PID to the displaced
1580 stepping state list, or return a pointer to an already existing
1581 entry, if it already exists. Never returns NULL. */
1583 static struct displaced_step_inferior_state *
1584 add_displaced_stepping_state (int pid)
1586 struct displaced_step_inferior_state *state;
1588 for (state = displaced_step_inferior_states;
1590 state = state->next)
1591 if (state->pid == pid)
1594 state = XCNEW (struct displaced_step_inferior_state);
1596 state->next = displaced_step_inferior_states;
1597 displaced_step_inferior_states = state;
1602 /* If inferior is in displaced stepping, and ADDR equals to starting address
1603 of copy area, return corresponding displaced_step_closure. Otherwise,
1606 struct displaced_step_closure*
1607 get_displaced_step_closure_by_addr (CORE_ADDR addr)
1609 struct displaced_step_inferior_state *displaced
1610 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
1612 /* If checking the mode of displaced instruction in copy area. */
1613 if (displaced && !ptid_equal (displaced->step_ptid, null_ptid)
1614 && (displaced->step_copy == addr))
1615 return displaced->step_closure;
1620 /* Remove the displaced stepping state of process PID. */
1623 remove_displaced_stepping_state (int pid)
1625 struct displaced_step_inferior_state *it, **prev_next_p;
1627 gdb_assert (pid != 0);
1629 it = displaced_step_inferior_states;
1630 prev_next_p = &displaced_step_inferior_states;
1635 *prev_next_p = it->next;
1640 prev_next_p = &it->next;
1646 infrun_inferior_exit (struct inferior *inf)
1648 remove_displaced_stepping_state (inf->pid);
1651 /* If ON, and the architecture supports it, GDB will use displaced
1652 stepping to step over breakpoints. If OFF, or if the architecture
1653 doesn't support it, GDB will instead use the traditional
1654 hold-and-step approach. If AUTO (which is the default), GDB will
1655 decide which technique to use to step over breakpoints depending on
1656 which of all-stop or non-stop mode is active --- displaced stepping
1657 in non-stop mode; hold-and-step in all-stop mode. */
1659 static enum auto_boolean can_use_displaced_stepping = AUTO_BOOLEAN_AUTO;
1662 show_can_use_displaced_stepping (struct ui_file *file, int from_tty,
1663 struct cmd_list_element *c,
1666 if (can_use_displaced_stepping == AUTO_BOOLEAN_AUTO)
1667 fprintf_filtered (file,
1668 _("Debugger's willingness to use displaced stepping "
1669 "to step over breakpoints is %s (currently %s).\n"),
1670 value, target_is_non_stop_p () ? "on" : "off");
1672 fprintf_filtered (file,
1673 _("Debugger's willingness to use displaced stepping "
1674 "to step over breakpoints is %s.\n"), value);
1677 /* Return non-zero if displaced stepping can/should be used to step
1678 over breakpoints of thread TP. */
1681 use_displaced_stepping (struct thread_info *tp)
1683 struct regcache *regcache = get_thread_regcache (tp->ptid);
1684 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1685 struct displaced_step_inferior_state *displaced_state;
1687 displaced_state = get_displaced_stepping_state (ptid_get_pid (tp->ptid));
1689 return (((can_use_displaced_stepping == AUTO_BOOLEAN_AUTO
1690 && target_is_non_stop_p ())
1691 || can_use_displaced_stepping == AUTO_BOOLEAN_TRUE)
1692 && gdbarch_displaced_step_copy_insn_p (gdbarch)
1693 && find_record_target () == NULL
1694 && (displaced_state == NULL
1695 || !displaced_state->failed_before));
1698 /* Clean out any stray displaced stepping state. */
1700 displaced_step_clear (struct displaced_step_inferior_state *displaced)
1702 /* Indicate that there is no cleanup pending. */
1703 displaced->step_ptid = null_ptid;
1705 if (displaced->step_closure)
1707 gdbarch_displaced_step_free_closure (displaced->step_gdbarch,
1708 displaced->step_closure);
1709 displaced->step_closure = NULL;
1714 displaced_step_clear_cleanup (void *arg)
1716 struct displaced_step_inferior_state *state
1717 = (struct displaced_step_inferior_state *) arg;
1719 displaced_step_clear (state);
1722 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1724 displaced_step_dump_bytes (struct ui_file *file,
1725 const gdb_byte *buf,
1730 for (i = 0; i < len; i++)
1731 fprintf_unfiltered (file, "%02x ", buf[i]);
1732 fputs_unfiltered ("\n", file);
1735 /* Prepare to single-step, using displaced stepping.
1737 Note that we cannot use displaced stepping when we have a signal to
1738 deliver. If we have a signal to deliver and an instruction to step
1739 over, then after the step, there will be no indication from the
1740 target whether the thread entered a signal handler or ignored the
1741 signal and stepped over the instruction successfully --- both cases
1742 result in a simple SIGTRAP. In the first case we mustn't do a
1743 fixup, and in the second case we must --- but we can't tell which.
1744 Comments in the code for 'random signals' in handle_inferior_event
1745 explain how we handle this case instead.
1747 Returns 1 if preparing was successful -- this thread is going to be
1748 stepped now; 0 if displaced stepping this thread got queued; or -1
1749 if this instruction can't be displaced stepped. */
1752 displaced_step_prepare_throw (ptid_t ptid)
1754 struct cleanup *old_cleanups, *ignore_cleanups;
1755 struct thread_info *tp = find_thread_ptid (ptid);
1756 struct regcache *regcache = get_thread_regcache (ptid);
1757 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1758 struct address_space *aspace = get_regcache_aspace (regcache);
1759 CORE_ADDR original, copy;
1761 struct displaced_step_closure *closure;
1762 struct displaced_step_inferior_state *displaced;
1765 /* We should never reach this function if the architecture does not
1766 support displaced stepping. */
1767 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch));
1769 /* Nor if the thread isn't meant to step over a breakpoint. */
1770 gdb_assert (tp->control.trap_expected);
1772 /* Disable range stepping while executing in the scratch pad. We
1773 want a single-step even if executing the displaced instruction in
1774 the scratch buffer lands within the stepping range (e.g., a
1776 tp->control.may_range_step = 0;
1778 /* We have to displaced step one thread at a time, as we only have
1779 access to a single scratch space per inferior. */
1781 displaced = add_displaced_stepping_state (ptid_get_pid (ptid));
1783 if (!ptid_equal (displaced->step_ptid, null_ptid))
1785 /* Already waiting for a displaced step to finish. Defer this
1786 request and place in queue. */
1788 if (debug_displaced)
1789 fprintf_unfiltered (gdb_stdlog,
1790 "displaced: deferring step of %s\n",
1791 target_pid_to_str (ptid));
1793 thread_step_over_chain_enqueue (tp);
1798 if (debug_displaced)
1799 fprintf_unfiltered (gdb_stdlog,
1800 "displaced: stepping %s now\n",
1801 target_pid_to_str (ptid));
1804 displaced_step_clear (displaced);
1806 old_cleanups = save_inferior_ptid ();
1807 inferior_ptid = ptid;
1809 original = regcache_read_pc (regcache);
1811 copy = gdbarch_displaced_step_location (gdbarch);
1812 len = gdbarch_max_insn_length (gdbarch);
1814 if (breakpoint_in_range_p (aspace, copy, len))
1816 /* There's a breakpoint set in the scratch pad location range
1817 (which is usually around the entry point). We'd either
1818 install it before resuming, which would overwrite/corrupt the
1819 scratch pad, or if it was already inserted, this displaced
1820 step would overwrite it. The latter is OK in the sense that
1821 we already assume that no thread is going to execute the code
1822 in the scratch pad range (after initial startup) anyway, but
1823 the former is unacceptable. Simply punt and fallback to
1824 stepping over this breakpoint in-line. */
1825 if (debug_displaced)
1827 fprintf_unfiltered (gdb_stdlog,
1828 "displaced: breakpoint set in scratch pad. "
1829 "Stepping over breakpoint in-line instead.\n");
1832 do_cleanups (old_cleanups);
1836 /* Save the original contents of the copy area. */
1837 displaced->step_saved_copy = (gdb_byte *) xmalloc (len);
1838 ignore_cleanups = make_cleanup (free_current_contents,
1839 &displaced->step_saved_copy);
1840 status = target_read_memory (copy, displaced->step_saved_copy, len);
1842 throw_error (MEMORY_ERROR,
1843 _("Error accessing memory address %s (%s) for "
1844 "displaced-stepping scratch space."),
1845 paddress (gdbarch, copy), safe_strerror (status));
1846 if (debug_displaced)
1848 fprintf_unfiltered (gdb_stdlog, "displaced: saved %s: ",
1849 paddress (gdbarch, copy));
1850 displaced_step_dump_bytes (gdb_stdlog,
1851 displaced->step_saved_copy,
1855 closure = gdbarch_displaced_step_copy_insn (gdbarch,
1856 original, copy, regcache);
1857 if (closure == NULL)
1859 /* The architecture doesn't know how or want to displaced step
1860 this instruction or instruction sequence. Fallback to
1861 stepping over the breakpoint in-line. */
1862 do_cleanups (old_cleanups);
1866 /* Save the information we need to fix things up if the step
1868 displaced->step_ptid = ptid;
1869 displaced->step_gdbarch = gdbarch;
1870 displaced->step_closure = closure;
1871 displaced->step_original = original;
1872 displaced->step_copy = copy;
1874 make_cleanup (displaced_step_clear_cleanup, displaced);
1876 /* Resume execution at the copy. */
1877 regcache_write_pc (regcache, copy);
1879 discard_cleanups (ignore_cleanups);
1881 do_cleanups (old_cleanups);
1883 if (debug_displaced)
1884 fprintf_unfiltered (gdb_stdlog, "displaced: displaced pc to %s\n",
1885 paddress (gdbarch, copy));
1890 /* Wrapper for displaced_step_prepare_throw that disabled further
1891 attempts at displaced stepping if we get a memory error. */
1894 displaced_step_prepare (ptid_t ptid)
1900 prepared = displaced_step_prepare_throw (ptid);
1902 CATCH (ex, RETURN_MASK_ERROR)
1904 struct displaced_step_inferior_state *displaced_state;
1906 if (ex.error != MEMORY_ERROR
1907 && ex.error != NOT_SUPPORTED_ERROR)
1908 throw_exception (ex);
1912 fprintf_unfiltered (gdb_stdlog,
1913 "infrun: disabling displaced stepping: %s\n",
1917 /* Be verbose if "set displaced-stepping" is "on", silent if
1919 if (can_use_displaced_stepping == AUTO_BOOLEAN_TRUE)
1921 warning (_("disabling displaced stepping: %s"),
1925 /* Disable further displaced stepping attempts. */
1927 = get_displaced_stepping_state (ptid_get_pid (ptid));
1928 displaced_state->failed_before = 1;
1936 write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr,
1937 const gdb_byte *myaddr, int len)
1939 struct cleanup *ptid_cleanup = save_inferior_ptid ();
1941 inferior_ptid = ptid;
1942 write_memory (memaddr, myaddr, len);
1943 do_cleanups (ptid_cleanup);
1946 /* Restore the contents of the copy area for thread PTID. */
1949 displaced_step_restore (struct displaced_step_inferior_state *displaced,
1952 ULONGEST len = gdbarch_max_insn_length (displaced->step_gdbarch);
1954 write_memory_ptid (ptid, displaced->step_copy,
1955 displaced->step_saved_copy, len);
1956 if (debug_displaced)
1957 fprintf_unfiltered (gdb_stdlog, "displaced: restored %s %s\n",
1958 target_pid_to_str (ptid),
1959 paddress (displaced->step_gdbarch,
1960 displaced->step_copy));
1963 /* If we displaced stepped an instruction successfully, adjust
1964 registers and memory to yield the same effect the instruction would
1965 have had if we had executed it at its original address, and return
1966 1. If the instruction didn't complete, relocate the PC and return
1967 -1. If the thread wasn't displaced stepping, return 0. */
1970 displaced_step_fixup (ptid_t event_ptid, enum gdb_signal signal)
1972 struct cleanup *old_cleanups;
1973 struct displaced_step_inferior_state *displaced
1974 = get_displaced_stepping_state (ptid_get_pid (event_ptid));
1977 /* Was any thread of this process doing a displaced step? */
1978 if (displaced == NULL)
1981 /* Was this event for the pid we displaced? */
1982 if (ptid_equal (displaced->step_ptid, null_ptid)
1983 || ! ptid_equal (displaced->step_ptid, event_ptid))
1986 old_cleanups = make_cleanup (displaced_step_clear_cleanup, displaced);
1988 displaced_step_restore (displaced, displaced->step_ptid);
1990 /* Fixup may need to read memory/registers. Switch to the thread
1991 that we're fixing up. Also, target_stopped_by_watchpoint checks
1992 the current thread. */
1993 switch_to_thread (event_ptid);
1995 /* Did the instruction complete successfully? */
1996 if (signal == GDB_SIGNAL_TRAP
1997 && !(target_stopped_by_watchpoint ()
1998 && (gdbarch_have_nonsteppable_watchpoint (displaced->step_gdbarch)
1999 || target_have_steppable_watchpoint)))
2001 /* Fix up the resulting state. */
2002 gdbarch_displaced_step_fixup (displaced->step_gdbarch,
2003 displaced->step_closure,
2004 displaced->step_original,
2005 displaced->step_copy,
2006 get_thread_regcache (displaced->step_ptid));
2011 /* Since the instruction didn't complete, all we can do is
2013 struct regcache *regcache = get_thread_regcache (event_ptid);
2014 CORE_ADDR pc = regcache_read_pc (regcache);
2016 pc = displaced->step_original + (pc - displaced->step_copy);
2017 regcache_write_pc (regcache, pc);
2021 do_cleanups (old_cleanups);
2023 displaced->step_ptid = null_ptid;
2028 /* Data to be passed around while handling an event. This data is
2029 discarded between events. */
2030 struct execution_control_state
2033 /* The thread that got the event, if this was a thread event; NULL
2035 struct thread_info *event_thread;
2037 struct target_waitstatus ws;
2038 int stop_func_filled_in;
2039 CORE_ADDR stop_func_start;
2040 CORE_ADDR stop_func_end;
2041 const char *stop_func_name;
2044 /* True if the event thread hit the single-step breakpoint of
2045 another thread. Thus the event doesn't cause a stop, the thread
2046 needs to be single-stepped past the single-step breakpoint before
2047 we can switch back to the original stepping thread. */
2048 int hit_singlestep_breakpoint;
2051 /* Clear ECS and set it to point at TP. */
2054 reset_ecs (struct execution_control_state *ecs, struct thread_info *tp)
2056 memset (ecs, 0, sizeof (*ecs));
2057 ecs->event_thread = tp;
2058 ecs->ptid = tp->ptid;
2061 static void keep_going_pass_signal (struct execution_control_state *ecs);
2062 static void prepare_to_wait (struct execution_control_state *ecs);
2063 static int keep_going_stepped_thread (struct thread_info *tp);
2064 static step_over_what thread_still_needs_step_over (struct thread_info *tp);
2066 /* Are there any pending step-over requests? If so, run all we can
2067 now and return true. Otherwise, return false. */
2070 start_step_over (void)
2072 struct thread_info *tp, *next;
2074 /* Don't start a new step-over if we already have an in-line
2075 step-over operation ongoing. */
2076 if (step_over_info_valid_p ())
2079 for (tp = step_over_queue_head; tp != NULL; tp = next)
2081 struct execution_control_state ecss;
2082 struct execution_control_state *ecs = &ecss;
2083 step_over_what step_what;
2084 int must_be_in_line;
2086 next = thread_step_over_chain_next (tp);
2088 /* If this inferior already has a displaced step in process,
2089 don't start a new one. */
2090 if (displaced_step_in_progress (ptid_get_pid (tp->ptid)))
2093 step_what = thread_still_needs_step_over (tp);
2094 must_be_in_line = ((step_what & STEP_OVER_WATCHPOINT)
2095 || ((step_what & STEP_OVER_BREAKPOINT)
2096 && !use_displaced_stepping (tp)));
2098 /* We currently stop all threads of all processes to step-over
2099 in-line. If we need to start a new in-line step-over, let
2100 any pending displaced steps finish first. */
2101 if (must_be_in_line && displaced_step_in_progress_any_inferior ())
2104 thread_step_over_chain_remove (tp);
2106 if (step_over_queue_head == NULL)
2109 fprintf_unfiltered (gdb_stdlog,
2110 "infrun: step-over queue now empty\n");
2113 if (tp->control.trap_expected
2117 internal_error (__FILE__, __LINE__,
2118 "[%s] has inconsistent state: "
2119 "trap_expected=%d, resumed=%d, executing=%d\n",
2120 target_pid_to_str (tp->ptid),
2121 tp->control.trap_expected,
2127 fprintf_unfiltered (gdb_stdlog,
2128 "infrun: resuming [%s] for step-over\n",
2129 target_pid_to_str (tp->ptid));
2131 /* keep_going_pass_signal skips the step-over if the breakpoint
2132 is no longer inserted. In all-stop, we want to keep looking
2133 for a thread that needs a step-over instead of resuming TP,
2134 because we wouldn't be able to resume anything else until the
2135 target stops again. In non-stop, the resume always resumes
2136 only TP, so it's OK to let the thread resume freely. */
2137 if (!target_is_non_stop_p () && !step_what)
2140 switch_to_thread (tp->ptid);
2141 reset_ecs (ecs, tp);
2142 keep_going_pass_signal (ecs);
2144 if (!ecs->wait_some_more)
2145 error (_("Command aborted."));
2147 gdb_assert (tp->resumed);
2149 /* If we started a new in-line step-over, we're done. */
2150 if (step_over_info_valid_p ())
2152 gdb_assert (tp->control.trap_expected);
2156 if (!target_is_non_stop_p ())
2158 /* On all-stop, shouldn't have resumed unless we needed a
2160 gdb_assert (tp->control.trap_expected
2161 || tp->step_after_step_resume_breakpoint);
2163 /* With remote targets (at least), in all-stop, we can't
2164 issue any further remote commands until the program stops
2169 /* Either the thread no longer needed a step-over, or a new
2170 displaced stepping sequence started. Even in the latter
2171 case, continue looking. Maybe we can also start another
2172 displaced step on a thread of other process. */
2178 /* Update global variables holding ptids to hold NEW_PTID if they were
2179 holding OLD_PTID. */
2181 infrun_thread_ptid_changed (ptid_t old_ptid, ptid_t new_ptid)
2183 struct displaced_step_inferior_state *displaced;
2185 if (ptid_equal (inferior_ptid, old_ptid))
2186 inferior_ptid = new_ptid;
2188 for (displaced = displaced_step_inferior_states;
2190 displaced = displaced->next)
2192 if (ptid_equal (displaced->step_ptid, old_ptid))
2193 displaced->step_ptid = new_ptid;
2200 /* Things to clean up if we QUIT out of resume (). */
2202 resume_cleanups (void *ignore)
2204 if (!ptid_equal (inferior_ptid, null_ptid))
2205 delete_single_step_breakpoints (inferior_thread ());
2210 static const char schedlock_off[] = "off";
2211 static const char schedlock_on[] = "on";
2212 static const char schedlock_step[] = "step";
2213 static const char schedlock_replay[] = "replay";
2214 static const char *const scheduler_enums[] = {
2221 static const char *scheduler_mode = schedlock_replay;
2223 show_scheduler_mode (struct ui_file *file, int from_tty,
2224 struct cmd_list_element *c, const char *value)
2226 fprintf_filtered (file,
2227 _("Mode for locking scheduler "
2228 "during execution is \"%s\".\n"),
2233 set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
2235 if (!target_can_lock_scheduler)
2237 scheduler_mode = schedlock_off;
2238 error (_("Target '%s' cannot support this command."), target_shortname);
2242 /* True if execution commands resume all threads of all processes by
2243 default; otherwise, resume only threads of the current inferior
2245 int sched_multi = 0;
2247 /* Try to setup for software single stepping over the specified location.
2248 Return 1 if target_resume() should use hardware single step.
2250 GDBARCH the current gdbarch.
2251 PC the location to step over. */
2254 maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc)
2258 if (execution_direction == EXEC_FORWARD
2259 && gdbarch_software_single_step_p (gdbarch)
2260 && gdbarch_software_single_step (gdbarch, get_current_frame ()))
2270 user_visible_resume_ptid (int step)
2276 /* With non-stop mode on, threads are always handled
2278 resume_ptid = inferior_ptid;
2280 else if ((scheduler_mode == schedlock_on)
2281 || (scheduler_mode == schedlock_step && step))
2283 /* User-settable 'scheduler' mode requires solo thread
2285 resume_ptid = inferior_ptid;
2287 else if ((scheduler_mode == schedlock_replay)
2288 && target_record_will_replay (minus_one_ptid, execution_direction))
2290 /* User-settable 'scheduler' mode requires solo thread resume in replay
2292 resume_ptid = inferior_ptid;
2294 else if (!sched_multi && target_supports_multi_process ())
2296 /* Resume all threads of the current process (and none of other
2298 resume_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
2302 /* Resume all threads of all processes. */
2303 resume_ptid = RESUME_ALL;
2309 /* Return a ptid representing the set of threads that we will resume,
2310 in the perspective of the target, assuming run control handling
2311 does not require leaving some threads stopped (e.g., stepping past
2312 breakpoint). USER_STEP indicates whether we're about to start the
2313 target for a stepping command. */
2316 internal_resume_ptid (int user_step)
2318 /* In non-stop, we always control threads individually. Note that
2319 the target may always work in non-stop mode even with "set
2320 non-stop off", in which case user_visible_resume_ptid could
2321 return a wildcard ptid. */
2322 if (target_is_non_stop_p ())
2323 return inferior_ptid;
2325 return user_visible_resume_ptid (user_step);
2328 /* Wrapper for target_resume, that handles infrun-specific
2332 do_target_resume (ptid_t resume_ptid, int step, enum gdb_signal sig)
2334 struct thread_info *tp = inferior_thread ();
2336 /* Install inferior's terminal modes. */
2337 target_terminal_inferior ();
2339 /* Avoid confusing the next resume, if the next stop/resume
2340 happens to apply to another thread. */
2341 tp->suspend.stop_signal = GDB_SIGNAL_0;
2343 /* Advise target which signals may be handled silently.
2345 If we have removed breakpoints because we are stepping over one
2346 in-line (in any thread), we need to receive all signals to avoid
2347 accidentally skipping a breakpoint during execution of a signal
2350 Likewise if we're displaced stepping, otherwise a trap for a
2351 breakpoint in a signal handler might be confused with the
2352 displaced step finishing. We don't make the displaced_step_fixup
2353 step distinguish the cases instead, because:
2355 - a backtrace while stopped in the signal handler would show the
2356 scratch pad as frame older than the signal handler, instead of
2357 the real mainline code.
2359 - when the thread is later resumed, the signal handler would
2360 return to the scratch pad area, which would no longer be
2362 if (step_over_info_valid_p ()
2363 || displaced_step_in_progress (ptid_get_pid (tp->ptid)))
2364 target_pass_signals (0, NULL);
2366 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
2368 target_resume (resume_ptid, step, sig);
2371 /* Resume the inferior, but allow a QUIT. This is useful if the user
2372 wants to interrupt some lengthy single-stepping operation
2373 (for child processes, the SIGINT goes to the inferior, and so
2374 we get a SIGINT random_signal, but for remote debugging and perhaps
2375 other targets, that's not true).
2377 SIG is the signal to give the inferior (zero for none). */
2379 resume (enum gdb_signal sig)
2381 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
2382 struct regcache *regcache = get_current_regcache ();
2383 struct gdbarch *gdbarch = get_regcache_arch (regcache);
2384 struct thread_info *tp = inferior_thread ();
2385 CORE_ADDR pc = regcache_read_pc (regcache);
2386 struct address_space *aspace = get_regcache_aspace (regcache);
2388 /* This represents the user's step vs continue request. When
2389 deciding whether "set scheduler-locking step" applies, it's the
2390 user's intention that counts. */
2391 const int user_step = tp->control.stepping_command;
2392 /* This represents what we'll actually request the target to do.
2393 This can decay from a step to a continue, if e.g., we need to
2394 implement single-stepping with breakpoints (software
2398 gdb_assert (!thread_is_in_step_over_chain (tp));
2402 if (tp->suspend.waitstatus_pending_p)
2408 statstr = target_waitstatus_to_string (&tp->suspend.waitstatus);
2409 fprintf_unfiltered (gdb_stdlog,
2410 "infrun: resume: thread %s has pending wait status %s "
2411 "(currently_stepping=%d).\n",
2412 target_pid_to_str (tp->ptid), statstr,
2413 currently_stepping (tp));
2419 /* FIXME: What should we do if we are supposed to resume this
2420 thread with a signal? Maybe we should maintain a queue of
2421 pending signals to deliver. */
2422 if (sig != GDB_SIGNAL_0)
2424 warning (_("Couldn't deliver signal %s to %s."),
2425 gdb_signal_to_name (sig), target_pid_to_str (tp->ptid));
2428 tp->suspend.stop_signal = GDB_SIGNAL_0;
2429 discard_cleanups (old_cleanups);
2431 if (target_can_async_p ())
2436 tp->stepped_breakpoint = 0;
2438 /* Depends on stepped_breakpoint. */
2439 step = currently_stepping (tp);
2441 if (current_inferior ()->waiting_for_vfork_done)
2443 /* Don't try to single-step a vfork parent that is waiting for
2444 the child to get out of the shared memory region (by exec'ing
2445 or exiting). This is particularly important on software
2446 single-step archs, as the child process would trip on the
2447 software single step breakpoint inserted for the parent
2448 process. Since the parent will not actually execute any
2449 instruction until the child is out of the shared region (such
2450 are vfork's semantics), it is safe to simply continue it.
2451 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2452 the parent, and tell it to `keep_going', which automatically
2453 re-sets it stepping. */
2455 fprintf_unfiltered (gdb_stdlog,
2456 "infrun: resume : clear step\n");
2461 fprintf_unfiltered (gdb_stdlog,
2462 "infrun: resume (step=%d, signal=%s), "
2463 "trap_expected=%d, current thread [%s] at %s\n",
2464 step, gdb_signal_to_symbol_string (sig),
2465 tp->control.trap_expected,
2466 target_pid_to_str (inferior_ptid),
2467 paddress (gdbarch, pc));
2469 /* Normally, by the time we reach `resume', the breakpoints are either
2470 removed or inserted, as appropriate. The exception is if we're sitting
2471 at a permanent breakpoint; we need to step over it, but permanent
2472 breakpoints can't be removed. So we have to test for it here. */
2473 if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here)
2475 if (sig != GDB_SIGNAL_0)
2477 /* We have a signal to pass to the inferior. The resume
2478 may, or may not take us to the signal handler. If this
2479 is a step, we'll need to stop in the signal handler, if
2480 there's one, (if the target supports stepping into
2481 handlers), or in the next mainline instruction, if
2482 there's no handler. If this is a continue, we need to be
2483 sure to run the handler with all breakpoints inserted.
2484 In all cases, set a breakpoint at the current address
2485 (where the handler returns to), and once that breakpoint
2486 is hit, resume skipping the permanent breakpoint. If
2487 that breakpoint isn't hit, then we've stepped into the
2488 signal handler (or hit some other event). We'll delete
2489 the step-resume breakpoint then. */
2492 fprintf_unfiltered (gdb_stdlog,
2493 "infrun: resume: skipping permanent breakpoint, "
2494 "deliver signal first\n");
2496 clear_step_over_info ();
2497 tp->control.trap_expected = 0;
2499 if (tp->control.step_resume_breakpoint == NULL)
2501 /* Set a "high-priority" step-resume, as we don't want
2502 user breakpoints at PC to trigger (again) when this
2504 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2505 gdb_assert (tp->control.step_resume_breakpoint->loc->permanent);
2507 tp->step_after_step_resume_breakpoint = step;
2510 insert_breakpoints ();
2514 /* There's no signal to pass, we can go ahead and skip the
2515 permanent breakpoint manually. */
2517 fprintf_unfiltered (gdb_stdlog,
2518 "infrun: resume: skipping permanent breakpoint\n");
2519 gdbarch_skip_permanent_breakpoint (gdbarch, regcache);
2520 /* Update pc to reflect the new address from which we will
2521 execute instructions. */
2522 pc = regcache_read_pc (regcache);
2526 /* We've already advanced the PC, so the stepping part
2527 is done. Now we need to arrange for a trap to be
2528 reported to handle_inferior_event. Set a breakpoint
2529 at the current PC, and run to it. Don't update
2530 prev_pc, because if we end in
2531 switch_back_to_stepped_thread, we want the "expected
2532 thread advanced also" branch to be taken. IOW, we
2533 don't want this thread to step further from PC
2535 gdb_assert (!step_over_info_valid_p ());
2536 insert_single_step_breakpoint (gdbarch, aspace, pc);
2537 insert_breakpoints ();
2539 resume_ptid = internal_resume_ptid (user_step);
2540 do_target_resume (resume_ptid, 0, GDB_SIGNAL_0);
2541 discard_cleanups (old_cleanups);
2548 /* If we have a breakpoint to step over, make sure to do a single
2549 step only. Same if we have software watchpoints. */
2550 if (tp->control.trap_expected || bpstat_should_step ())
2551 tp->control.may_range_step = 0;
2553 /* If enabled, step over breakpoints by executing a copy of the
2554 instruction at a different address.
2556 We can't use displaced stepping when we have a signal to deliver;
2557 the comments for displaced_step_prepare explain why. The
2558 comments in the handle_inferior event for dealing with 'random
2559 signals' explain what we do instead.
2561 We can't use displaced stepping when we are waiting for vfork_done
2562 event, displaced stepping breaks the vfork child similarly as single
2563 step software breakpoint. */
2564 if (tp->control.trap_expected
2565 && use_displaced_stepping (tp)
2566 && !step_over_info_valid_p ()
2567 && sig == GDB_SIGNAL_0
2568 && !current_inferior ()->waiting_for_vfork_done)
2570 int prepared = displaced_step_prepare (inferior_ptid);
2575 fprintf_unfiltered (gdb_stdlog,
2576 "Got placed in step-over queue\n");
2578 tp->control.trap_expected = 0;
2579 discard_cleanups (old_cleanups);
2582 else if (prepared < 0)
2584 /* Fallback to stepping over the breakpoint in-line. */
2586 if (target_is_non_stop_p ())
2587 stop_all_threads ();
2589 set_step_over_info (get_regcache_aspace (regcache),
2590 regcache_read_pc (regcache), 0, tp->global_num);
2592 step = maybe_software_singlestep (gdbarch, pc);
2594 insert_breakpoints ();
2596 else if (prepared > 0)
2598 struct displaced_step_inferior_state *displaced;
2600 /* Update pc to reflect the new address from which we will
2601 execute instructions due to displaced stepping. */
2602 pc = regcache_read_pc (get_thread_regcache (inferior_ptid));
2604 displaced = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
2605 step = gdbarch_displaced_step_hw_singlestep (gdbarch,
2606 displaced->step_closure);
2610 /* Do we need to do it the hard way, w/temp breakpoints? */
2612 step = maybe_software_singlestep (gdbarch, pc);
2614 /* Currently, our software single-step implementation leads to different
2615 results than hardware single-stepping in one situation: when stepping
2616 into delivering a signal which has an associated signal handler,
2617 hardware single-step will stop at the first instruction of the handler,
2618 while software single-step will simply skip execution of the handler.
2620 For now, this difference in behavior is accepted since there is no
2621 easy way to actually implement single-stepping into a signal handler
2622 without kernel support.
2624 However, there is one scenario where this difference leads to follow-on
2625 problems: if we're stepping off a breakpoint by removing all breakpoints
2626 and then single-stepping. In this case, the software single-step
2627 behavior means that even if there is a *breakpoint* in the signal
2628 handler, GDB still would not stop.
2630 Fortunately, we can at least fix this particular issue. We detect
2631 here the case where we are about to deliver a signal while software
2632 single-stepping with breakpoints removed. In this situation, we
2633 revert the decisions to remove all breakpoints and insert single-
2634 step breakpoints, and instead we install a step-resume breakpoint
2635 at the current address, deliver the signal without stepping, and
2636 once we arrive back at the step-resume breakpoint, actually step
2637 over the breakpoint we originally wanted to step over. */
2638 if (thread_has_single_step_breakpoints_set (tp)
2639 && sig != GDB_SIGNAL_0
2640 && step_over_info_valid_p ())
2642 /* If we have nested signals or a pending signal is delivered
2643 immediately after a handler returns, might might already have
2644 a step-resume breakpoint set on the earlier handler. We cannot
2645 set another step-resume breakpoint; just continue on until the
2646 original breakpoint is hit. */
2647 if (tp->control.step_resume_breakpoint == NULL)
2649 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2650 tp->step_after_step_resume_breakpoint = 1;
2653 delete_single_step_breakpoints (tp);
2655 clear_step_over_info ();
2656 tp->control.trap_expected = 0;
2658 insert_breakpoints ();
2661 /* If STEP is set, it's a request to use hardware stepping
2662 facilities. But in that case, we should never
2663 use singlestep breakpoint. */
2664 gdb_assert (!(thread_has_single_step_breakpoints_set (tp) && step));
2666 /* Decide the set of threads to ask the target to resume. */
2667 if (tp->control.trap_expected)
2669 /* We're allowing a thread to run past a breakpoint it has
2670 hit, either by single-stepping the thread with the breakpoint
2671 removed, or by displaced stepping, with the breakpoint inserted.
2672 In the former case, we need to single-step only this thread,
2673 and keep others stopped, as they can miss this breakpoint if
2674 allowed to run. That's not really a problem for displaced
2675 stepping, but, we still keep other threads stopped, in case
2676 another thread is also stopped for a breakpoint waiting for
2677 its turn in the displaced stepping queue. */
2678 resume_ptid = inferior_ptid;
2681 resume_ptid = internal_resume_ptid (user_step);
2683 if (execution_direction != EXEC_REVERSE
2684 && step && breakpoint_inserted_here_p (aspace, pc))
2686 /* There are two cases where we currently need to step a
2687 breakpoint instruction when we have a signal to deliver:
2689 - See handle_signal_stop where we handle random signals that
2690 could take out us out of the stepping range. Normally, in
2691 that case we end up continuing (instead of stepping) over the
2692 signal handler with a breakpoint at PC, but there are cases
2693 where we should _always_ single-step, even if we have a
2694 step-resume breakpoint, like when a software watchpoint is
2695 set. Assuming single-stepping and delivering a signal at the
2696 same time would takes us to the signal handler, then we could
2697 have removed the breakpoint at PC to step over it. However,
2698 some hardware step targets (like e.g., Mac OS) can't step
2699 into signal handlers, and for those, we need to leave the
2700 breakpoint at PC inserted, as otherwise if the handler
2701 recurses and executes PC again, it'll miss the breakpoint.
2702 So we leave the breakpoint inserted anyway, but we need to
2703 record that we tried to step a breakpoint instruction, so
2704 that adjust_pc_after_break doesn't end up confused.
2706 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2707 in one thread after another thread that was stepping had been
2708 momentarily paused for a step-over. When we re-resume the
2709 stepping thread, it may be resumed from that address with a
2710 breakpoint that hasn't trapped yet. Seen with
2711 gdb.threads/non-stop-fair-events.exp, on targets that don't
2712 do displaced stepping. */
2715 fprintf_unfiltered (gdb_stdlog,
2716 "infrun: resume: [%s] stepped breakpoint\n",
2717 target_pid_to_str (tp->ptid));
2719 tp->stepped_breakpoint = 1;
2721 /* Most targets can step a breakpoint instruction, thus
2722 executing it normally. But if this one cannot, just
2723 continue and we will hit it anyway. */
2724 if (gdbarch_cannot_step_breakpoint (gdbarch))
2729 && tp->control.trap_expected
2730 && use_displaced_stepping (tp)
2731 && !step_over_info_valid_p ())
2733 struct regcache *resume_regcache = get_thread_regcache (tp->ptid);
2734 struct gdbarch *resume_gdbarch = get_regcache_arch (resume_regcache);
2735 CORE_ADDR actual_pc = regcache_read_pc (resume_regcache);
2738 fprintf_unfiltered (gdb_stdlog, "displaced: run %s: ",
2739 paddress (resume_gdbarch, actual_pc));
2740 read_memory (actual_pc, buf, sizeof (buf));
2741 displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
2744 if (tp->control.may_range_step)
2746 /* If we're resuming a thread with the PC out of the step
2747 range, then we're doing some nested/finer run control
2748 operation, like stepping the thread out of the dynamic
2749 linker or the displaced stepping scratch pad. We
2750 shouldn't have allowed a range step then. */
2751 gdb_assert (pc_in_thread_step_range (pc, tp));
2754 do_target_resume (resume_ptid, step, sig);
2756 discard_cleanups (old_cleanups);
2763 /* Counter that tracks number of user visible stops. This can be used
2764 to tell whether a command has proceeded the inferior past the
2765 current location. This allows e.g., inferior function calls in
2766 breakpoint commands to not interrupt the command list. When the
2767 call finishes successfully, the inferior is standing at the same
2768 breakpoint as if nothing happened (and so we don't call
2770 static ULONGEST current_stop_id;
2777 return current_stop_id;
2780 /* Called when we report a user visible stop. */
2788 /* Clear out all variables saying what to do when inferior is continued.
2789 First do this, then set the ones you want, then call `proceed'. */
2792 clear_proceed_status_thread (struct thread_info *tp)
2795 fprintf_unfiltered (gdb_stdlog,
2796 "infrun: clear_proceed_status_thread (%s)\n",
2797 target_pid_to_str (tp->ptid));
2799 /* If we're starting a new sequence, then the previous finished
2800 single-step is no longer relevant. */
2801 if (tp->suspend.waitstatus_pending_p)
2803 if (tp->suspend.stop_reason == TARGET_STOPPED_BY_SINGLE_STEP)
2806 fprintf_unfiltered (gdb_stdlog,
2807 "infrun: clear_proceed_status: pending "
2808 "event of %s was a finished step. "
2810 target_pid_to_str (tp->ptid));
2812 tp->suspend.waitstatus_pending_p = 0;
2813 tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON;
2815 else if (debug_infrun)
2819 statstr = target_waitstatus_to_string (&tp->suspend.waitstatus);
2820 fprintf_unfiltered (gdb_stdlog,
2821 "infrun: clear_proceed_status_thread: thread %s "
2822 "has pending wait status %s "
2823 "(currently_stepping=%d).\n",
2824 target_pid_to_str (tp->ptid), statstr,
2825 currently_stepping (tp));
2830 /* If this signal should not be seen by program, give it zero.
2831 Used for debugging signals. */
2832 if (!signal_pass_state (tp->suspend.stop_signal))
2833 tp->suspend.stop_signal = GDB_SIGNAL_0;
2835 thread_fsm_delete (tp->thread_fsm);
2836 tp->thread_fsm = NULL;
2838 tp->control.trap_expected = 0;
2839 tp->control.step_range_start = 0;
2840 tp->control.step_range_end = 0;
2841 tp->control.may_range_step = 0;
2842 tp->control.step_frame_id = null_frame_id;
2843 tp->control.step_stack_frame_id = null_frame_id;
2844 tp->control.step_over_calls = STEP_OVER_UNDEBUGGABLE;
2845 tp->control.step_start_function = NULL;
2846 tp->stop_requested = 0;
2848 tp->control.stop_step = 0;
2850 tp->control.proceed_to_finish = 0;
2852 tp->control.stepping_command = 0;
2854 /* Discard any remaining commands or status from previous stop. */
2855 bpstat_clear (&tp->control.stop_bpstat);
2859 clear_proceed_status (int step)
2861 /* With scheduler-locking replay, stop replaying other threads if we're
2862 not replaying the user-visible resume ptid.
2864 This is a convenience feature to not require the user to explicitly
2865 stop replaying the other threads. We're assuming that the user's
2866 intent is to resume tracing the recorded process. */
2867 if (!non_stop && scheduler_mode == schedlock_replay
2868 && target_record_is_replaying (minus_one_ptid)
2869 && !target_record_will_replay (user_visible_resume_ptid (step),
2870 execution_direction))
2871 target_record_stop_replaying ();
2875 struct thread_info *tp;
2878 resume_ptid = user_visible_resume_ptid (step);
2880 /* In all-stop mode, delete the per-thread status of all threads
2881 we're about to resume, implicitly and explicitly. */
2882 ALL_NON_EXITED_THREADS (tp)
2884 if (!ptid_match (tp->ptid, resume_ptid))
2886 clear_proceed_status_thread (tp);
2890 if (!ptid_equal (inferior_ptid, null_ptid))
2892 struct inferior *inferior;
2896 /* If in non-stop mode, only delete the per-thread status of
2897 the current thread. */
2898 clear_proceed_status_thread (inferior_thread ());
2901 inferior = current_inferior ();
2902 inferior->control.stop_soon = NO_STOP_QUIETLY;
2905 observer_notify_about_to_proceed ();
2908 /* Returns true if TP is still stopped at a breakpoint that needs
2909 stepping-over in order to make progress. If the breakpoint is gone
2910 meanwhile, we can skip the whole step-over dance. */
2913 thread_still_needs_step_over_bp (struct thread_info *tp)
2915 if (tp->stepping_over_breakpoint)
2917 struct regcache *regcache = get_thread_regcache (tp->ptid);
2919 if (breakpoint_here_p (get_regcache_aspace (regcache),
2920 regcache_read_pc (regcache))
2921 == ordinary_breakpoint_here)
2924 tp->stepping_over_breakpoint = 0;
2930 /* Check whether thread TP still needs to start a step-over in order
2931 to make progress when resumed. Returns an bitwise or of enum
2932 step_over_what bits, indicating what needs to be stepped over. */
2934 static step_over_what
2935 thread_still_needs_step_over (struct thread_info *tp)
2937 step_over_what what = 0;
2939 if (thread_still_needs_step_over_bp (tp))
2940 what |= STEP_OVER_BREAKPOINT;
2942 if (tp->stepping_over_watchpoint
2943 && !target_have_steppable_watchpoint)
2944 what |= STEP_OVER_WATCHPOINT;
2949 /* Returns true if scheduler locking applies. STEP indicates whether
2950 we're about to do a step/next-like command to a thread. */
2953 schedlock_applies (struct thread_info *tp)
2955 return (scheduler_mode == schedlock_on
2956 || (scheduler_mode == schedlock_step
2957 && tp->control.stepping_command)
2958 || (scheduler_mode == schedlock_replay
2959 && target_record_will_replay (minus_one_ptid,
2960 execution_direction)));
2963 /* Basic routine for continuing the program in various fashions.
2965 ADDR is the address to resume at, or -1 for resume where stopped.
2966 SIGGNAL is the signal to give it, or 0 for none,
2967 or -1 for act according to how it stopped.
2968 STEP is nonzero if should trap after one instruction.
2969 -1 means return after that and print nothing.
2970 You should probably set various step_... variables
2971 before calling here, if you are stepping.
2973 You should call clear_proceed_status before calling proceed. */
2976 proceed (CORE_ADDR addr, enum gdb_signal siggnal)
2978 struct regcache *regcache;
2979 struct gdbarch *gdbarch;
2980 struct thread_info *tp;
2982 struct address_space *aspace;
2984 struct execution_control_state ecss;
2985 struct execution_control_state *ecs = &ecss;
2986 struct cleanup *old_chain;
2989 /* If we're stopped at a fork/vfork, follow the branch set by the
2990 "set follow-fork-mode" command; otherwise, we'll just proceed
2991 resuming the current thread. */
2992 if (!follow_fork ())
2994 /* The target for some reason decided not to resume. */
2996 if (target_can_async_p ())
2997 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
3001 /* We'll update this if & when we switch to a new thread. */
3002 previous_inferior_ptid = inferior_ptid;
3004 regcache = get_current_regcache ();
3005 gdbarch = get_regcache_arch (regcache);
3006 aspace = get_regcache_aspace (regcache);
3007 pc = regcache_read_pc (regcache);
3008 tp = inferior_thread ();
3010 /* Fill in with reasonable starting values. */
3011 init_thread_stepping_state (tp);
3013 gdb_assert (!thread_is_in_step_over_chain (tp));
3015 if (addr == (CORE_ADDR) -1)
3018 && breakpoint_here_p (aspace, pc) == ordinary_breakpoint_here
3019 && execution_direction != EXEC_REVERSE)
3020 /* There is a breakpoint at the address we will resume at,
3021 step one instruction before inserting breakpoints so that
3022 we do not stop right away (and report a second hit at this
3025 Note, we don't do this in reverse, because we won't
3026 actually be executing the breakpoint insn anyway.
3027 We'll be (un-)executing the previous instruction. */
3028 tp->stepping_over_breakpoint = 1;
3029 else if (gdbarch_single_step_through_delay_p (gdbarch)
3030 && gdbarch_single_step_through_delay (gdbarch,
3031 get_current_frame ()))
3032 /* We stepped onto an instruction that needs to be stepped
3033 again before re-inserting the breakpoint, do so. */
3034 tp->stepping_over_breakpoint = 1;
3038 regcache_write_pc (regcache, addr);
3041 if (siggnal != GDB_SIGNAL_DEFAULT)
3042 tp->suspend.stop_signal = siggnal;
3044 resume_ptid = user_visible_resume_ptid (tp->control.stepping_command);
3046 /* If an exception is thrown from this point on, make sure to
3047 propagate GDB's knowledge of the executing state to the
3048 frontend/user running state. */
3049 old_chain = make_cleanup (finish_thread_state_cleanup, &resume_ptid);
3051 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3052 threads (e.g., we might need to set threads stepping over
3053 breakpoints first), from the user/frontend's point of view, all
3054 threads in RESUME_PTID are now running. Unless we're calling an
3055 inferior function, as in that case we pretend the inferior
3056 doesn't run at all. */
3057 if (!tp->control.in_infcall)
3058 set_running (resume_ptid, 1);
3061 fprintf_unfiltered (gdb_stdlog,
3062 "infrun: proceed (addr=%s, signal=%s)\n",
3063 paddress (gdbarch, addr),
3064 gdb_signal_to_symbol_string (siggnal));
3066 annotate_starting ();
3068 /* Make sure that output from GDB appears before output from the
3070 gdb_flush (gdb_stdout);
3072 /* In a multi-threaded task we may select another thread and
3073 then continue or step.
3075 But if a thread that we're resuming had stopped at a breakpoint,
3076 it will immediately cause another breakpoint stop without any
3077 execution (i.e. it will report a breakpoint hit incorrectly). So
3078 we must step over it first.
3080 Look for threads other than the current (TP) that reported a
3081 breakpoint hit and haven't been resumed yet since. */
3083 /* If scheduler locking applies, we can avoid iterating over all
3085 if (!non_stop && !schedlock_applies (tp))
3087 struct thread_info *current = tp;
3089 ALL_NON_EXITED_THREADS (tp)
3091 /* Ignore the current thread here. It's handled
3096 /* Ignore threads of processes we're not resuming. */
3097 if (!ptid_match (tp->ptid, resume_ptid))
3100 if (!thread_still_needs_step_over (tp))
3103 gdb_assert (!thread_is_in_step_over_chain (tp));
3106 fprintf_unfiltered (gdb_stdlog,
3107 "infrun: need to step-over [%s] first\n",
3108 target_pid_to_str (tp->ptid));
3110 thread_step_over_chain_enqueue (tp);
3116 /* Enqueue the current thread last, so that we move all other
3117 threads over their breakpoints first. */
3118 if (tp->stepping_over_breakpoint)
3119 thread_step_over_chain_enqueue (tp);
3121 /* If the thread isn't started, we'll still need to set its prev_pc,
3122 so that switch_back_to_stepped_thread knows the thread hasn't
3123 advanced. Must do this before resuming any thread, as in
3124 all-stop/remote, once we resume we can't send any other packet
3125 until the target stops again. */
3126 tp->prev_pc = regcache_read_pc (regcache);
3128 started = start_step_over ();
3130 if (step_over_info_valid_p ())
3132 /* Either this thread started a new in-line step over, or some
3133 other thread was already doing one. In either case, don't
3134 resume anything else until the step-over is finished. */
3136 else if (started && !target_is_non_stop_p ())
3138 /* A new displaced stepping sequence was started. In all-stop,
3139 we can't talk to the target anymore until it next stops. */
3141 else if (!non_stop && target_is_non_stop_p ())
3143 /* In all-stop, but the target is always in non-stop mode.
3144 Start all other threads that are implicitly resumed too. */
3145 ALL_NON_EXITED_THREADS (tp)
3147 /* Ignore threads of processes we're not resuming. */
3148 if (!ptid_match (tp->ptid, resume_ptid))
3154 fprintf_unfiltered (gdb_stdlog,
3155 "infrun: proceed: [%s] resumed\n",
3156 target_pid_to_str (tp->ptid));
3157 gdb_assert (tp->executing || tp->suspend.waitstatus_pending_p);
3161 if (thread_is_in_step_over_chain (tp))
3164 fprintf_unfiltered (gdb_stdlog,
3165 "infrun: proceed: [%s] needs step-over\n",
3166 target_pid_to_str (tp->ptid));
3171 fprintf_unfiltered (gdb_stdlog,
3172 "infrun: proceed: resuming %s\n",
3173 target_pid_to_str (tp->ptid));
3175 reset_ecs (ecs, tp);
3176 switch_to_thread (tp->ptid);
3177 keep_going_pass_signal (ecs);
3178 if (!ecs->wait_some_more)
3179 error (_("Command aborted."));
3182 else if (!tp->resumed && !thread_is_in_step_over_chain (tp))
3184 /* The thread wasn't started, and isn't queued, run it now. */
3185 reset_ecs (ecs, tp);
3186 switch_to_thread (tp->ptid);
3187 keep_going_pass_signal (ecs);
3188 if (!ecs->wait_some_more)
3189 error (_("Command aborted."));
3192 discard_cleanups (old_chain);
3194 /* Tell the event loop to wait for it to stop. If the target
3195 supports asynchronous execution, it'll do this from within
3197 if (!target_can_async_p ())
3198 mark_async_event_handler (infrun_async_inferior_event_token);
3202 /* Start remote-debugging of a machine over a serial link. */
3205 start_remote (int from_tty)
3207 struct inferior *inferior;
3209 inferior = current_inferior ();
3210 inferior->control.stop_soon = STOP_QUIETLY_REMOTE;
3212 /* Always go on waiting for the target, regardless of the mode. */
3213 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3214 indicate to wait_for_inferior that a target should timeout if
3215 nothing is returned (instead of just blocking). Because of this,
3216 targets expecting an immediate response need to, internally, set
3217 things up so that the target_wait() is forced to eventually
3219 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3220 differentiate to its caller what the state of the target is after
3221 the initial open has been performed. Here we're assuming that
3222 the target has stopped. It should be possible to eventually have
3223 target_open() return to the caller an indication that the target
3224 is currently running and GDB state should be set to the same as
3225 for an async run. */
3226 wait_for_inferior ();
3228 /* Now that the inferior has stopped, do any bookkeeping like
3229 loading shared libraries. We want to do this before normal_stop,
3230 so that the displayed frame is up to date. */
3231 post_create_inferior (¤t_target, from_tty);
3236 /* Initialize static vars when a new inferior begins. */
3239 init_wait_for_inferior (void)
3241 /* These are meaningless until the first time through wait_for_inferior. */
3243 breakpoint_init_inferior (inf_starting);
3245 clear_proceed_status (0);
3247 target_last_wait_ptid = minus_one_ptid;
3249 previous_inferior_ptid = inferior_ptid;
3251 /* Discard any skipped inlined frames. */
3252 clear_inline_frame_state (minus_one_ptid);
3257 static void handle_inferior_event (struct execution_control_state *ecs);
3259 static void handle_step_into_function (struct gdbarch *gdbarch,
3260 struct execution_control_state *ecs);
3261 static void handle_step_into_function_backward (struct gdbarch *gdbarch,
3262 struct execution_control_state *ecs);
3263 static void handle_signal_stop (struct execution_control_state *ecs);
3264 static void check_exception_resume (struct execution_control_state *,
3265 struct frame_info *);
3267 static void end_stepping_range (struct execution_control_state *ecs);
3268 static void stop_waiting (struct execution_control_state *ecs);
3269 static void keep_going (struct execution_control_state *ecs);
3270 static void process_event_stop_test (struct execution_control_state *ecs);
3271 static int switch_back_to_stepped_thread (struct execution_control_state *ecs);
3273 /* Callback for iterate over threads. If the thread is stopped, but
3274 the user/frontend doesn't know about that yet, go through
3275 normal_stop, as if the thread had just stopped now. ARG points at
3276 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
3277 ptid_is_pid(PTID) is true, applies to all threads of the process
3278 pointed at by PTID. Otherwise, apply only to the thread pointed by
3282 infrun_thread_stop_requested_callback (struct thread_info *info, void *arg)
3284 ptid_t ptid = * (ptid_t *) arg;
3286 if ((ptid_equal (info->ptid, ptid)
3287 || ptid_equal (minus_one_ptid, ptid)
3288 || (ptid_is_pid (ptid)
3289 && ptid_get_pid (ptid) == ptid_get_pid (info->ptid)))
3290 && is_running (info->ptid)
3291 && !is_executing (info->ptid))
3293 struct cleanup *old_chain;
3294 struct execution_control_state ecss;
3295 struct execution_control_state *ecs = &ecss;
3297 memset (ecs, 0, sizeof (*ecs));
3299 old_chain = make_cleanup_restore_current_thread ();
3301 overlay_cache_invalid = 1;
3302 /* Flush target cache before starting to handle each event.
3303 Target was running and cache could be stale. This is just a
3304 heuristic. Running threads may modify target memory, but we
3305 don't get any event. */
3306 target_dcache_invalidate ();
3308 /* Go through handle_inferior_event/normal_stop, so we always
3309 have consistent output as if the stop event had been
3311 ecs->ptid = info->ptid;
3312 ecs->event_thread = info;
3313 ecs->ws.kind = TARGET_WAITKIND_STOPPED;
3314 ecs->ws.value.sig = GDB_SIGNAL_0;
3316 handle_inferior_event (ecs);
3318 if (!ecs->wait_some_more)
3320 /* Cancel any running execution command. */
3321 thread_cancel_execution_command (info);
3326 do_cleanups (old_chain);
3332 /* This function is attached as a "thread_stop_requested" observer.
3333 Cleanup local state that assumed the PTID was to be resumed, and
3334 report the stop to the frontend. */
3337 infrun_thread_stop_requested (ptid_t ptid)
3339 struct thread_info *tp;
3341 /* PTID was requested to stop. Remove matching threads from the
3342 step-over queue, so we don't try to resume them
3344 ALL_NON_EXITED_THREADS (tp)
3345 if (ptid_match (tp->ptid, ptid))
3347 if (thread_is_in_step_over_chain (tp))
3348 thread_step_over_chain_remove (tp);
3351 iterate_over_threads (infrun_thread_stop_requested_callback, &ptid);
3355 infrun_thread_thread_exit (struct thread_info *tp, int silent)
3357 if (ptid_equal (target_last_wait_ptid, tp->ptid))
3358 nullify_last_target_wait_ptid ();
3361 /* Delete the step resume, single-step and longjmp/exception resume
3362 breakpoints of TP. */
3365 delete_thread_infrun_breakpoints (struct thread_info *tp)
3367 delete_step_resume_breakpoint (tp);
3368 delete_exception_resume_breakpoint (tp);
3369 delete_single_step_breakpoints (tp);
3372 /* If the target still has execution, call FUNC for each thread that
3373 just stopped. In all-stop, that's all the non-exited threads; in
3374 non-stop, that's the current thread, only. */
3376 typedef void (*for_each_just_stopped_thread_callback_func)
3377 (struct thread_info *tp);
3380 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func)
3382 if (!target_has_execution || ptid_equal (inferior_ptid, null_ptid))
3385 if (target_is_non_stop_p ())
3387 /* If in non-stop mode, only the current thread stopped. */
3388 func (inferior_thread ());
3392 struct thread_info *tp;
3394 /* In all-stop mode, all threads have stopped. */
3395 ALL_NON_EXITED_THREADS (tp)
3402 /* Delete the step resume and longjmp/exception resume breakpoints of
3403 the threads that just stopped. */
3406 delete_just_stopped_threads_infrun_breakpoints (void)
3408 for_each_just_stopped_thread (delete_thread_infrun_breakpoints);
3411 /* Delete the single-step breakpoints of the threads that just
3415 delete_just_stopped_threads_single_step_breakpoints (void)
3417 for_each_just_stopped_thread (delete_single_step_breakpoints);
3420 /* A cleanup wrapper. */
3423 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg)
3425 delete_just_stopped_threads_infrun_breakpoints ();
3431 print_target_wait_results (ptid_t waiton_ptid, ptid_t result_ptid,
3432 const struct target_waitstatus *ws)
3434 char *status_string = target_waitstatus_to_string (ws);
3435 struct ui_file *tmp_stream = mem_fileopen ();
3438 /* The text is split over several lines because it was getting too long.
3439 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3440 output as a unit; we want only one timestamp printed if debug_timestamp
3443 fprintf_unfiltered (tmp_stream,
3444 "infrun: target_wait (%d.%ld.%ld",
3445 ptid_get_pid (waiton_ptid),
3446 ptid_get_lwp (waiton_ptid),
3447 ptid_get_tid (waiton_ptid));
3448 if (ptid_get_pid (waiton_ptid) != -1)
3449 fprintf_unfiltered (tmp_stream,
3450 " [%s]", target_pid_to_str (waiton_ptid));
3451 fprintf_unfiltered (tmp_stream, ", status) =\n");
3452 fprintf_unfiltered (tmp_stream,
3453 "infrun: %d.%ld.%ld [%s],\n",
3454 ptid_get_pid (result_ptid),
3455 ptid_get_lwp (result_ptid),
3456 ptid_get_tid (result_ptid),
3457 target_pid_to_str (result_ptid));
3458 fprintf_unfiltered (tmp_stream,
3462 text = ui_file_xstrdup (tmp_stream, NULL);
3464 /* This uses %s in part to handle %'s in the text, but also to avoid
3465 a gcc error: the format attribute requires a string literal. */
3466 fprintf_unfiltered (gdb_stdlog, "%s", text);
3468 xfree (status_string);
3470 ui_file_delete (tmp_stream);
3473 /* Select a thread at random, out of those which are resumed and have
3476 static struct thread_info *
3477 random_pending_event_thread (ptid_t waiton_ptid)
3479 struct thread_info *event_tp;
3481 int random_selector;
3483 /* First see how many events we have. Count only resumed threads
3484 that have an event pending. */
3485 ALL_NON_EXITED_THREADS (event_tp)
3486 if (ptid_match (event_tp->ptid, waiton_ptid)
3487 && event_tp->resumed
3488 && event_tp->suspend.waitstatus_pending_p)
3491 if (num_events == 0)
3494 /* Now randomly pick a thread out of those that have had events. */
3495 random_selector = (int)
3496 ((num_events * (double) rand ()) / (RAND_MAX + 1.0));
3498 if (debug_infrun && num_events > 1)
3499 fprintf_unfiltered (gdb_stdlog,
3500 "infrun: Found %d events, selecting #%d\n",
3501 num_events, random_selector);
3503 /* Select the Nth thread that has had an event. */
3504 ALL_NON_EXITED_THREADS (event_tp)
3505 if (ptid_match (event_tp->ptid, waiton_ptid)
3506 && event_tp->resumed
3507 && event_tp->suspend.waitstatus_pending_p)
3508 if (random_selector-- == 0)
3514 /* Wrapper for target_wait that first checks whether threads have
3515 pending statuses to report before actually asking the target for
3519 do_target_wait (ptid_t ptid, struct target_waitstatus *status, int options)
3522 struct thread_info *tp;
3524 /* First check if there is a resumed thread with a wait status
3526 if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid))
3528 tp = random_pending_event_thread (ptid);
3533 fprintf_unfiltered (gdb_stdlog,
3534 "infrun: Waiting for specific thread %s.\n",
3535 target_pid_to_str (ptid));
3537 /* We have a specific thread to check. */
3538 tp = find_thread_ptid (ptid);
3539 gdb_assert (tp != NULL);
3540 if (!tp->suspend.waitstatus_pending_p)
3545 && (tp->suspend.stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3546 || tp->suspend.stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT))
3548 struct regcache *regcache = get_thread_regcache (tp->ptid);
3549 struct gdbarch *gdbarch = get_regcache_arch (regcache);
3553 pc = regcache_read_pc (regcache);
3555 if (pc != tp->suspend.stop_pc)
3558 fprintf_unfiltered (gdb_stdlog,
3559 "infrun: PC of %s changed. was=%s, now=%s\n",
3560 target_pid_to_str (tp->ptid),
3561 paddress (gdbarch, tp->prev_pc),
3562 paddress (gdbarch, pc));
3565 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc))
3568 fprintf_unfiltered (gdb_stdlog,
3569 "infrun: previous breakpoint of %s, at %s gone\n",
3570 target_pid_to_str (tp->ptid),
3571 paddress (gdbarch, pc));
3579 fprintf_unfiltered (gdb_stdlog,
3580 "infrun: pending event of %s cancelled.\n",
3581 target_pid_to_str (tp->ptid));
3583 tp->suspend.waitstatus.kind = TARGET_WAITKIND_SPURIOUS;
3584 tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON;
3594 statstr = target_waitstatus_to_string (&tp->suspend.waitstatus);
3595 fprintf_unfiltered (gdb_stdlog,
3596 "infrun: Using pending wait status %s for %s.\n",
3598 target_pid_to_str (tp->ptid));
3602 /* Now that we've selected our final event LWP, un-adjust its PC
3603 if it was a software breakpoint (and the target doesn't
3604 always adjust the PC itself). */
3605 if (tp->suspend.stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3606 && !target_supports_stopped_by_sw_breakpoint ())
3608 struct regcache *regcache;
3609 struct gdbarch *gdbarch;
3612 regcache = get_thread_regcache (tp->ptid);
3613 gdbarch = get_regcache_arch (regcache);
3615 decr_pc = gdbarch_decr_pc_after_break (gdbarch);
3620 pc = regcache_read_pc (regcache);
3621 regcache_write_pc (regcache, pc + decr_pc);
3625 tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON;
3626 *status = tp->suspend.waitstatus;
3627 tp->suspend.waitstatus_pending_p = 0;
3629 /* Wake up the event loop again, until all pending events are
3631 if (target_is_async_p ())
3632 mark_async_event_handler (infrun_async_inferior_event_token);
3636 /* But if we don't find one, we'll have to wait. */
3638 if (deprecated_target_wait_hook)
3639 event_ptid = deprecated_target_wait_hook (ptid, status, options);
3641 event_ptid = target_wait (ptid, status, options);
3646 /* Prepare and stabilize the inferior for detaching it. E.g.,
3647 detaching while a thread is displaced stepping is a recipe for
3648 crashing it, as nothing would readjust the PC out of the scratch
3652 prepare_for_detach (void)
3654 struct inferior *inf = current_inferior ();
3655 ptid_t pid_ptid = pid_to_ptid (inf->pid);
3656 struct cleanup *old_chain_1;
3657 struct displaced_step_inferior_state *displaced;
3659 displaced = get_displaced_stepping_state (inf->pid);
3661 /* Is any thread of this process displaced stepping? If not,
3662 there's nothing else to do. */
3663 if (displaced == NULL || ptid_equal (displaced->step_ptid, null_ptid))
3667 fprintf_unfiltered (gdb_stdlog,
3668 "displaced-stepping in-process while detaching");
3670 old_chain_1 = make_cleanup_restore_integer (&inf->detaching);
3673 while (!ptid_equal (displaced->step_ptid, null_ptid))
3675 struct cleanup *old_chain_2;
3676 struct execution_control_state ecss;
3677 struct execution_control_state *ecs;
3680 memset (ecs, 0, sizeof (*ecs));
3682 overlay_cache_invalid = 1;
3683 /* Flush target cache before starting to handle each event.
3684 Target was running and cache could be stale. This is just a
3685 heuristic. Running threads may modify target memory, but we
3686 don't get any event. */
3687 target_dcache_invalidate ();
3689 ecs->ptid = do_target_wait (pid_ptid, &ecs->ws, 0);
3692 print_target_wait_results (pid_ptid, ecs->ptid, &ecs->ws);
3694 /* If an error happens while handling the event, propagate GDB's
3695 knowledge of the executing state to the frontend/user running
3697 old_chain_2 = make_cleanup (finish_thread_state_cleanup,
3700 /* Now figure out what to do with the result of the result. */
3701 handle_inferior_event (ecs);
3703 /* No error, don't finish the state yet. */
3704 discard_cleanups (old_chain_2);
3706 /* Breakpoints and watchpoints are not installed on the target
3707 at this point, and signals are passed directly to the
3708 inferior, so this must mean the process is gone. */
3709 if (!ecs->wait_some_more)
3711 discard_cleanups (old_chain_1);
3712 error (_("Program exited while detaching"));
3716 discard_cleanups (old_chain_1);
3719 /* Wait for control to return from inferior to debugger.
3721 If inferior gets a signal, we may decide to start it up again
3722 instead of returning. That is why there is a loop in this function.
3723 When this function actually returns it means the inferior
3724 should be left stopped and GDB should read more commands. */
3727 wait_for_inferior (void)
3729 struct cleanup *old_cleanups;
3730 struct cleanup *thread_state_chain;
3734 (gdb_stdlog, "infrun: wait_for_inferior ()\n");
3737 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup,
3740 /* If an error happens while handling the event, propagate GDB's
3741 knowledge of the executing state to the frontend/user running
3743 thread_state_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
3747 struct execution_control_state ecss;
3748 struct execution_control_state *ecs = &ecss;
3749 ptid_t waiton_ptid = minus_one_ptid;
3751 memset (ecs, 0, sizeof (*ecs));
3753 overlay_cache_invalid = 1;
3755 /* Flush target cache before starting to handle each event.
3756 Target was running and cache could be stale. This is just a
3757 heuristic. Running threads may modify target memory, but we
3758 don't get any event. */
3759 target_dcache_invalidate ();
3761 ecs->ptid = do_target_wait (waiton_ptid, &ecs->ws, 0);
3764 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
3766 /* Now figure out what to do with the result of the result. */
3767 handle_inferior_event (ecs);
3769 if (!ecs->wait_some_more)
3773 /* No error, don't finish the state yet. */
3774 discard_cleanups (thread_state_chain);
3776 do_cleanups (old_cleanups);
3779 /* Cleanup that reinstalls the readline callback handler, if the
3780 target is running in the background. If while handling the target
3781 event something triggered a secondary prompt, like e.g., a
3782 pagination prompt, we'll have removed the callback handler (see
3783 gdb_readline_wrapper_line). Need to do this as we go back to the
3784 event loop, ready to process further input. Note this has no
3785 effect if the handler hasn't actually been removed, because calling
3786 rl_callback_handler_install resets the line buffer, thus losing
3790 reinstall_readline_callback_handler_cleanup (void *arg)
3792 struct ui *ui = current_ui;
3796 /* We're not going back to the top level event loop yet. Don't
3797 install the readline callback, as it'd prep the terminal,
3798 readline-style (raw, noecho) (e.g., --batch). We'll install
3799 it the next time the prompt is displayed, when we're ready
3804 if (ui->command_editing && ui->prompt_state != PROMPT_BLOCKED)
3805 gdb_rl_callback_handler_reinstall ();
3808 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3809 that's just the event thread. In all-stop, that's all threads. */
3812 clean_up_just_stopped_threads_fsms (struct execution_control_state *ecs)
3814 struct thread_info *thr = ecs->event_thread;
3816 if (thr != NULL && thr->thread_fsm != NULL)
3817 thread_fsm_clean_up (thr->thread_fsm, thr);
3821 ALL_NON_EXITED_THREADS (thr)
3823 if (thr->thread_fsm == NULL)
3825 if (thr == ecs->event_thread)
3828 switch_to_thread (thr->ptid);
3829 thread_fsm_clean_up (thr->thread_fsm, thr);
3832 if (ecs->event_thread != NULL)
3833 switch_to_thread (ecs->event_thread->ptid);
3837 /* Helper for all_uis_check_sync_execution_done that works on the
3841 check_curr_ui_sync_execution_done (void)
3843 struct ui *ui = current_ui;
3845 if (ui->prompt_state == PROMPT_NEEDED
3847 && !gdb_in_secondary_prompt_p (ui))
3849 target_terminal_ours ();
3850 observer_notify_sync_execution_done ();
3851 ui_register_input_event_handler (ui);
3858 all_uis_check_sync_execution_done (void)
3860 struct switch_thru_all_uis state;
3862 SWITCH_THRU_ALL_UIS (state)
3864 check_curr_ui_sync_execution_done ();
3871 all_uis_on_sync_execution_starting (void)
3873 struct switch_thru_all_uis state;
3875 SWITCH_THRU_ALL_UIS (state)
3877 if (current_ui->prompt_state == PROMPT_NEEDED)
3878 async_disable_stdin ();
3882 /* A cleanup that restores the execution direction to the value saved
3886 restore_execution_direction (void *arg)
3888 enum exec_direction_kind *save_exec_dir = (enum exec_direction_kind *) arg;
3890 execution_direction = *save_exec_dir;
3893 /* Asynchronous version of wait_for_inferior. It is called by the
3894 event loop whenever a change of state is detected on the file
3895 descriptor corresponding to the target. It can be called more than
3896 once to complete a single execution command. In such cases we need
3897 to keep the state in a global variable ECSS. If it is the last time
3898 that this function is called for a single execution command, then
3899 report to the user that the inferior has stopped, and do the
3900 necessary cleanups. */
3903 fetch_inferior_event (void *client_data)
3905 struct execution_control_state ecss;
3906 struct execution_control_state *ecs = &ecss;
3907 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
3908 struct cleanup *ts_old_chain;
3909 enum exec_direction_kind save_exec_dir = execution_direction;
3911 ptid_t waiton_ptid = minus_one_ptid;
3913 memset (ecs, 0, sizeof (*ecs));
3915 /* Events are always processed with the main UI as current UI. This
3916 way, warnings, debug output, etc. are always consistently sent to
3917 the main console. */
3918 make_cleanup (restore_ui_cleanup, current_ui);
3919 current_ui = main_ui;
3921 /* End up with readline processing input, if necessary. */
3922 make_cleanup (reinstall_readline_callback_handler_cleanup, NULL);
3924 /* We're handling a live event, so make sure we're doing live
3925 debugging. If we're looking at traceframes while the target is
3926 running, we're going to need to get back to that mode after
3927 handling the event. */
3930 make_cleanup_restore_current_traceframe ();
3931 set_current_traceframe (-1);
3935 /* In non-stop mode, the user/frontend should not notice a thread
3936 switch due to internal events. Make sure we reverse to the
3937 user selected thread and frame after handling the event and
3938 running any breakpoint commands. */
3939 make_cleanup_restore_current_thread ();
3941 overlay_cache_invalid = 1;
3942 /* Flush target cache before starting to handle each event. Target
3943 was running and cache could be stale. This is just a heuristic.
3944 Running threads may modify target memory, but we don't get any
3946 target_dcache_invalidate ();
3948 make_cleanup (restore_execution_direction, &save_exec_dir);
3949 execution_direction = target_execution_direction ();
3951 ecs->ptid = do_target_wait (waiton_ptid, &ecs->ws,
3952 target_can_async_p () ? TARGET_WNOHANG : 0);
3955 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
3957 /* If an error happens while handling the event, propagate GDB's
3958 knowledge of the executing state to the frontend/user running
3960 if (!target_is_non_stop_p ())
3961 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
3963 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &ecs->ptid);
3965 /* Get executed before make_cleanup_restore_current_thread above to apply
3966 still for the thread which has thrown the exception. */
3967 make_bpstat_clear_actions_cleanup ();
3969 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup, NULL);
3971 /* Now figure out what to do with the result of the result. */
3972 handle_inferior_event (ecs);
3974 if (!ecs->wait_some_more)
3976 struct inferior *inf = find_inferior_ptid (ecs->ptid);
3977 int should_stop = 1;
3978 struct thread_info *thr = ecs->event_thread;
3979 int should_notify_stop = 1;
3981 delete_just_stopped_threads_infrun_breakpoints ();
3985 struct thread_fsm *thread_fsm = thr->thread_fsm;
3987 if (thread_fsm != NULL)
3988 should_stop = thread_fsm_should_stop (thread_fsm, thr);
3997 clean_up_just_stopped_threads_fsms (ecs);
3999 if (thr != NULL && thr->thread_fsm != NULL)
4002 = thread_fsm_should_notify_stop (thr->thread_fsm);
4005 if (should_notify_stop)
4009 /* We may not find an inferior if this was a process exit. */
4010 if (inf == NULL || inf->control.stop_soon == NO_STOP_QUIETLY)
4011 proceeded = normal_stop ();
4015 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
4022 /* No error, don't finish the thread states yet. */
4023 discard_cleanups (ts_old_chain);
4025 /* Revert thread and frame. */
4026 do_cleanups (old_chain);
4028 /* If a UI was in sync execution mode, and now isn't, restore its
4029 prompt (a synchronous execution command has finished, and we're
4030 ready for input). */
4031 all_uis_check_sync_execution_done ();
4034 && exec_done_display_p
4035 && (ptid_equal (inferior_ptid, null_ptid)
4036 || !is_running (inferior_ptid)))
4037 printf_unfiltered (_("completed.\n"));
4040 /* Record the frame and location we're currently stepping through. */
4042 set_step_info (struct frame_info *frame, struct symtab_and_line sal)
4044 struct thread_info *tp = inferior_thread ();
4046 tp->control.step_frame_id = get_frame_id (frame);
4047 tp->control.step_stack_frame_id = get_stack_frame_id (frame);
4049 tp->current_symtab = sal.symtab;
4050 tp->current_line = sal.line;
4053 /* Clear context switchable stepping state. */
4056 init_thread_stepping_state (struct thread_info *tss)
4058 tss->stepped_breakpoint = 0;
4059 tss->stepping_over_breakpoint = 0;
4060 tss->stepping_over_watchpoint = 0;
4061 tss->step_after_step_resume_breakpoint = 0;
4064 /* Set the cached copy of the last ptid/waitstatus. */
4067 set_last_target_status (ptid_t ptid, struct target_waitstatus status)
4069 target_last_wait_ptid = ptid;
4070 target_last_waitstatus = status;
4073 /* Return the cached copy of the last pid/waitstatus returned by
4074 target_wait()/deprecated_target_wait_hook(). The data is actually
4075 cached by handle_inferior_event(), which gets called immediately
4076 after target_wait()/deprecated_target_wait_hook(). */
4079 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
4081 *ptidp = target_last_wait_ptid;
4082 *status = target_last_waitstatus;
4086 nullify_last_target_wait_ptid (void)
4088 target_last_wait_ptid = minus_one_ptid;
4091 /* Switch thread contexts. */
4094 context_switch (ptid_t ptid)
4096 if (debug_infrun && !ptid_equal (ptid, inferior_ptid))
4098 fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ",
4099 target_pid_to_str (inferior_ptid));
4100 fprintf_unfiltered (gdb_stdlog, "to %s\n",
4101 target_pid_to_str (ptid));
4104 switch_to_thread (ptid);
4107 /* If the target can't tell whether we've hit breakpoints
4108 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4109 check whether that could have been caused by a breakpoint. If so,
4110 adjust the PC, per gdbarch_decr_pc_after_break. */
4113 adjust_pc_after_break (struct thread_info *thread,
4114 struct target_waitstatus *ws)
4116 struct regcache *regcache;
4117 struct gdbarch *gdbarch;
4118 struct address_space *aspace;
4119 CORE_ADDR breakpoint_pc, decr_pc;
4121 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4122 we aren't, just return.
4124 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4125 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4126 implemented by software breakpoints should be handled through the normal
4129 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4130 different signals (SIGILL or SIGEMT for instance), but it is less
4131 clear where the PC is pointing afterwards. It may not match
4132 gdbarch_decr_pc_after_break. I don't know any specific target that
4133 generates these signals at breakpoints (the code has been in GDB since at
4134 least 1992) so I can not guess how to handle them here.
4136 In earlier versions of GDB, a target with
4137 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4138 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4139 target with both of these set in GDB history, and it seems unlikely to be
4140 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4142 if (ws->kind != TARGET_WAITKIND_STOPPED)
4145 if (ws->value.sig != GDB_SIGNAL_TRAP)
4148 /* In reverse execution, when a breakpoint is hit, the instruction
4149 under it has already been de-executed. The reported PC always
4150 points at the breakpoint address, so adjusting it further would
4151 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4154 B1 0x08000000 : INSN1
4155 B2 0x08000001 : INSN2
4157 PC -> 0x08000003 : INSN4
4159 Say you're stopped at 0x08000003 as above. Reverse continuing
4160 from that point should hit B2 as below. Reading the PC when the
4161 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4162 been de-executed already.
4164 B1 0x08000000 : INSN1
4165 B2 PC -> 0x08000001 : INSN2
4169 We can't apply the same logic as for forward execution, because
4170 we would wrongly adjust the PC to 0x08000000, since there's a
4171 breakpoint at PC - 1. We'd then report a hit on B1, although
4172 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4174 if (execution_direction == EXEC_REVERSE)
4177 /* If the target can tell whether the thread hit a SW breakpoint,
4178 trust it. Targets that can tell also adjust the PC
4180 if (target_supports_stopped_by_sw_breakpoint ())
4183 /* Note that relying on whether a breakpoint is planted in memory to
4184 determine this can fail. E.g,. the breakpoint could have been
4185 removed since. Or the thread could have been told to step an
4186 instruction the size of a breakpoint instruction, and only
4187 _after_ was a breakpoint inserted at its address. */
4189 /* If this target does not decrement the PC after breakpoints, then
4190 we have nothing to do. */
4191 regcache = get_thread_regcache (thread->ptid);
4192 gdbarch = get_regcache_arch (regcache);
4194 decr_pc = gdbarch_decr_pc_after_break (gdbarch);
4198 aspace = get_regcache_aspace (regcache);
4200 /* Find the location where (if we've hit a breakpoint) the
4201 breakpoint would be. */
4202 breakpoint_pc = regcache_read_pc (regcache) - decr_pc;
4204 /* If the target can't tell whether a software breakpoint triggered,
4205 fallback to figuring it out based on breakpoints we think were
4206 inserted in the target, and on whether the thread was stepped or
4209 /* Check whether there actually is a software breakpoint inserted at
4212 If in non-stop mode, a race condition is possible where we've
4213 removed a breakpoint, but stop events for that breakpoint were
4214 already queued and arrive later. To suppress those spurious
4215 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4216 and retire them after a number of stop events are reported. Note
4217 this is an heuristic and can thus get confused. The real fix is
4218 to get the "stopped by SW BP and needs adjustment" info out of
4219 the target/kernel (and thus never reach here; see above). */
4220 if (software_breakpoint_inserted_here_p (aspace, breakpoint_pc)
4221 || (target_is_non_stop_p ()
4222 && moribund_breakpoint_here_p (aspace, breakpoint_pc)))
4224 struct cleanup *old_cleanups = make_cleanup (null_cleanup, NULL);
4226 if (record_full_is_used ())
4227 record_full_gdb_operation_disable_set ();
4229 /* When using hardware single-step, a SIGTRAP is reported for both
4230 a completed single-step and a software breakpoint. Need to
4231 differentiate between the two, as the latter needs adjusting
4232 but the former does not.
4234 The SIGTRAP can be due to a completed hardware single-step only if
4235 - we didn't insert software single-step breakpoints
4236 - this thread is currently being stepped
4238 If any of these events did not occur, we must have stopped due
4239 to hitting a software breakpoint, and have to back up to the
4242 As a special case, we could have hardware single-stepped a
4243 software breakpoint. In this case (prev_pc == breakpoint_pc),
4244 we also need to back up to the breakpoint address. */
4246 if (thread_has_single_step_breakpoints_set (thread)
4247 || !currently_stepping (thread)
4248 || (thread->stepped_breakpoint
4249 && thread->prev_pc == breakpoint_pc))
4250 regcache_write_pc (regcache, breakpoint_pc);
4252 do_cleanups (old_cleanups);
4257 stepped_in_from (struct frame_info *frame, struct frame_id step_frame_id)
4259 for (frame = get_prev_frame (frame);
4261 frame = get_prev_frame (frame))
4263 if (frame_id_eq (get_frame_id (frame), step_frame_id))
4265 if (get_frame_type (frame) != INLINE_FRAME)
4272 /* Auxiliary function that handles syscall entry/return events.
4273 It returns 1 if the inferior should keep going (and GDB
4274 should ignore the event), or 0 if the event deserves to be
4278 handle_syscall_event (struct execution_control_state *ecs)
4280 struct regcache *regcache;
4283 if (!ptid_equal (ecs->ptid, inferior_ptid))
4284 context_switch (ecs->ptid);
4286 regcache = get_thread_regcache (ecs->ptid);
4287 syscall_number = ecs->ws.value.syscall_number;
4288 stop_pc = regcache_read_pc (regcache);
4290 if (catch_syscall_enabled () > 0
4291 && catching_syscall_number (syscall_number) > 0)
4294 fprintf_unfiltered (gdb_stdlog, "infrun: syscall number = '%d'\n",
4297 ecs->event_thread->control.stop_bpstat
4298 = bpstat_stop_status (get_regcache_aspace (regcache),
4299 stop_pc, ecs->ptid, &ecs->ws);
4301 if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
4303 /* Catchpoint hit. */
4308 /* If no catchpoint triggered for this, then keep going. */
4313 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4316 fill_in_stop_func (struct gdbarch *gdbarch,
4317 struct execution_control_state *ecs)
4319 if (!ecs->stop_func_filled_in)
4321 /* Don't care about return value; stop_func_start and stop_func_name
4322 will both be 0 if it doesn't work. */
4323 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
4324 &ecs->stop_func_start, &ecs->stop_func_end);
4325 ecs->stop_func_start
4326 += gdbarch_deprecated_function_start_offset (gdbarch);
4328 if (gdbarch_skip_entrypoint_p (gdbarch))
4329 ecs->stop_func_start = gdbarch_skip_entrypoint (gdbarch,
4330 ecs->stop_func_start);
4332 ecs->stop_func_filled_in = 1;
4337 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4339 static enum stop_kind
4340 get_inferior_stop_soon (ptid_t ptid)
4342 struct inferior *inf = find_inferior_ptid (ptid);
4344 gdb_assert (inf != NULL);
4345 return inf->control.stop_soon;
4348 /* Wait for one event. Store the resulting waitstatus in WS, and
4349 return the event ptid. */
4352 wait_one (struct target_waitstatus *ws)
4355 ptid_t wait_ptid = minus_one_ptid;
4357 overlay_cache_invalid = 1;
4359 /* Flush target cache before starting to handle each event.
4360 Target was running and cache could be stale. This is just a
4361 heuristic. Running threads may modify target memory, but we
4362 don't get any event. */
4363 target_dcache_invalidate ();
4365 if (deprecated_target_wait_hook)
4366 event_ptid = deprecated_target_wait_hook (wait_ptid, ws, 0);
4368 event_ptid = target_wait (wait_ptid, ws, 0);
4371 print_target_wait_results (wait_ptid, event_ptid, ws);
4376 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4377 instead of the current thread. */
4378 #define THREAD_STOPPED_BY(REASON) \
4380 thread_stopped_by_ ## REASON (ptid_t ptid) \
4382 struct cleanup *old_chain; \
4385 old_chain = save_inferior_ptid (); \
4386 inferior_ptid = ptid; \
4388 res = target_stopped_by_ ## REASON (); \
4390 do_cleanups (old_chain); \
4395 /* Generate thread_stopped_by_watchpoint. */
4396 THREAD_STOPPED_BY (watchpoint)
4397 /* Generate thread_stopped_by_sw_breakpoint. */
4398 THREAD_STOPPED_BY (sw_breakpoint)
4399 /* Generate thread_stopped_by_hw_breakpoint. */
4400 THREAD_STOPPED_BY (hw_breakpoint)
4402 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4405 switch_to_thread_cleanup (void *ptid_p)
4407 ptid_t ptid = *(ptid_t *) ptid_p;
4409 switch_to_thread (ptid);
4412 /* Save the thread's event and stop reason to process it later. */
4415 save_waitstatus (struct thread_info *tp, struct target_waitstatus *ws)
4417 struct regcache *regcache;
4418 struct address_space *aspace;
4424 statstr = target_waitstatus_to_string (ws);
4425 fprintf_unfiltered (gdb_stdlog,
4426 "infrun: saving status %s for %d.%ld.%ld\n",
4428 ptid_get_pid (tp->ptid),
4429 ptid_get_lwp (tp->ptid),
4430 ptid_get_tid (tp->ptid));
4434 /* Record for later. */
4435 tp->suspend.waitstatus = *ws;
4436 tp->suspend.waitstatus_pending_p = 1;
4438 regcache = get_thread_regcache (tp->ptid);
4439 aspace = get_regcache_aspace (regcache);
4441 if (ws->kind == TARGET_WAITKIND_STOPPED
4442 && ws->value.sig == GDB_SIGNAL_TRAP)
4444 CORE_ADDR pc = regcache_read_pc (regcache);
4446 adjust_pc_after_break (tp, &tp->suspend.waitstatus);
4448 if (thread_stopped_by_watchpoint (tp->ptid))
4450 tp->suspend.stop_reason
4451 = TARGET_STOPPED_BY_WATCHPOINT;
4453 else if (target_supports_stopped_by_sw_breakpoint ()
4454 && thread_stopped_by_sw_breakpoint (tp->ptid))
4456 tp->suspend.stop_reason
4457 = TARGET_STOPPED_BY_SW_BREAKPOINT;
4459 else if (target_supports_stopped_by_hw_breakpoint ()
4460 && thread_stopped_by_hw_breakpoint (tp->ptid))
4462 tp->suspend.stop_reason
4463 = TARGET_STOPPED_BY_HW_BREAKPOINT;
4465 else if (!target_supports_stopped_by_hw_breakpoint ()
4466 && hardware_breakpoint_inserted_here_p (aspace,
4469 tp->suspend.stop_reason
4470 = TARGET_STOPPED_BY_HW_BREAKPOINT;
4472 else if (!target_supports_stopped_by_sw_breakpoint ()
4473 && software_breakpoint_inserted_here_p (aspace,
4476 tp->suspend.stop_reason
4477 = TARGET_STOPPED_BY_SW_BREAKPOINT;
4479 else if (!thread_has_single_step_breakpoints_set (tp)
4480 && currently_stepping (tp))
4482 tp->suspend.stop_reason
4483 = TARGET_STOPPED_BY_SINGLE_STEP;
4488 /* A cleanup that disables thread create/exit events. */
4491 disable_thread_events (void *arg)
4493 target_thread_events (0);
4499 stop_all_threads (void)
4501 /* We may need multiple passes to discover all threads. */
4505 struct cleanup *old_chain;
4507 gdb_assert (target_is_non_stop_p ());
4510 fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads\n");
4512 entry_ptid = inferior_ptid;
4513 old_chain = make_cleanup (switch_to_thread_cleanup, &entry_ptid);
4515 target_thread_events (1);
4516 make_cleanup (disable_thread_events, NULL);
4518 /* Request threads to stop, and then wait for the stops. Because
4519 threads we already know about can spawn more threads while we're
4520 trying to stop them, and we only learn about new threads when we
4521 update the thread list, do this in a loop, and keep iterating
4522 until two passes find no threads that need to be stopped. */
4523 for (pass = 0; pass < 2; pass++, iterations++)
4526 fprintf_unfiltered (gdb_stdlog,
4527 "infrun: stop_all_threads, pass=%d, "
4528 "iterations=%d\n", pass, iterations);
4532 struct target_waitstatus ws;
4534 struct thread_info *t;
4536 update_thread_list ();
4538 /* Go through all threads looking for threads that we need
4539 to tell the target to stop. */
4540 ALL_NON_EXITED_THREADS (t)
4544 /* If already stopping, don't request a stop again.
4545 We just haven't seen the notification yet. */
4546 if (!t->stop_requested)
4549 fprintf_unfiltered (gdb_stdlog,
4550 "infrun: %s executing, "
4552 target_pid_to_str (t->ptid));
4553 target_stop (t->ptid);
4554 t->stop_requested = 1;
4559 fprintf_unfiltered (gdb_stdlog,
4560 "infrun: %s executing, "
4561 "already stopping\n",
4562 target_pid_to_str (t->ptid));
4565 if (t->stop_requested)
4571 fprintf_unfiltered (gdb_stdlog,
4572 "infrun: %s not executing\n",
4573 target_pid_to_str (t->ptid));
4575 /* The thread may be not executing, but still be
4576 resumed with a pending status to process. */
4584 /* If we find new threads on the second iteration, restart
4585 over. We want to see two iterations in a row with all
4590 event_ptid = wait_one (&ws);
4591 if (ws.kind == TARGET_WAITKIND_NO_RESUMED)
4593 /* All resumed threads exited. */
4595 else if (ws.kind == TARGET_WAITKIND_THREAD_EXITED
4596 || ws.kind == TARGET_WAITKIND_EXITED
4597 || ws.kind == TARGET_WAITKIND_SIGNALLED)
4601 ptid_t ptid = pid_to_ptid (ws.value.integer);
4603 fprintf_unfiltered (gdb_stdlog,
4604 "infrun: %s exited while "
4605 "stopping threads\n",
4606 target_pid_to_str (ptid));
4611 struct inferior *inf;
4613 t = find_thread_ptid (event_ptid);
4615 t = add_thread (event_ptid);
4617 t->stop_requested = 0;
4620 t->control.may_range_step = 0;
4622 /* This may be the first time we see the inferior report
4624 inf = find_inferior_ptid (event_ptid);
4625 if (inf->needs_setup)
4627 switch_to_thread_no_regs (t);
4631 if (ws.kind == TARGET_WAITKIND_STOPPED
4632 && ws.value.sig == GDB_SIGNAL_0)
4634 /* We caught the event that we intended to catch, so
4635 there's no event pending. */
4636 t->suspend.waitstatus.kind = TARGET_WAITKIND_IGNORE;
4637 t->suspend.waitstatus_pending_p = 0;
4639 if (displaced_step_fixup (t->ptid, GDB_SIGNAL_0) < 0)
4641 /* Add it back to the step-over queue. */
4644 fprintf_unfiltered (gdb_stdlog,
4645 "infrun: displaced-step of %s "
4646 "canceled: adding back to the "
4647 "step-over queue\n",
4648 target_pid_to_str (t->ptid));
4650 t->control.trap_expected = 0;
4651 thread_step_over_chain_enqueue (t);
4656 enum gdb_signal sig;
4657 struct regcache *regcache;
4663 statstr = target_waitstatus_to_string (&ws);
4664 fprintf_unfiltered (gdb_stdlog,
4665 "infrun: target_wait %s, saving "
4666 "status for %d.%ld.%ld\n",
4668 ptid_get_pid (t->ptid),
4669 ptid_get_lwp (t->ptid),
4670 ptid_get_tid (t->ptid));
4674 /* Record for later. */
4675 save_waitstatus (t, &ws);
4677 sig = (ws.kind == TARGET_WAITKIND_STOPPED
4678 ? ws.value.sig : GDB_SIGNAL_0);
4680 if (displaced_step_fixup (t->ptid, sig) < 0)
4682 /* Add it back to the step-over queue. */
4683 t->control.trap_expected = 0;
4684 thread_step_over_chain_enqueue (t);
4687 regcache = get_thread_regcache (t->ptid);
4688 t->suspend.stop_pc = regcache_read_pc (regcache);
4692 fprintf_unfiltered (gdb_stdlog,
4693 "infrun: saved stop_pc=%s for %s "
4694 "(currently_stepping=%d)\n",
4695 paddress (target_gdbarch (),
4696 t->suspend.stop_pc),
4697 target_pid_to_str (t->ptid),
4698 currently_stepping (t));
4705 do_cleanups (old_chain);
4708 fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads done\n");
4711 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4714 handle_no_resumed (struct execution_control_state *ecs)
4716 struct inferior *inf;
4717 struct thread_info *thread;
4719 if (target_can_async_p ())
4726 if (ui->prompt_state == PROMPT_BLOCKED)
4734 /* There were no unwaited-for children left in the target, but,
4735 we're not synchronously waiting for events either. Just
4739 fprintf_unfiltered (gdb_stdlog,
4740 "infrun: TARGET_WAITKIND_NO_RESUMED "
4741 "(ignoring: bg)\n");
4742 prepare_to_wait (ecs);
4747 /* Otherwise, if we were running a synchronous execution command, we
4748 may need to cancel it and give the user back the terminal.
4750 In non-stop mode, the target can't tell whether we've already
4751 consumed previous stop events, so it can end up sending us a
4752 no-resumed event like so:
4754 #0 - thread 1 is left stopped
4756 #1 - thread 2 is resumed and hits breakpoint
4757 -> TARGET_WAITKIND_STOPPED
4759 #2 - thread 3 is resumed and exits
4760 this is the last resumed thread, so
4761 -> TARGET_WAITKIND_NO_RESUMED
4763 #3 - gdb processes stop for thread 2 and decides to re-resume
4766 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4767 thread 2 is now resumed, so the event should be ignored.
4769 IOW, if the stop for thread 2 doesn't end a foreground command,
4770 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4771 event. But it could be that the event meant that thread 2 itself
4772 (or whatever other thread was the last resumed thread) exited.
4774 To address this we refresh the thread list and check whether we
4775 have resumed threads _now_. In the example above, this removes
4776 thread 3 from the thread list. If thread 2 was re-resumed, we
4777 ignore this event. If we find no thread resumed, then we cancel
4778 the synchronous command show "no unwaited-for " to the user. */
4779 update_thread_list ();
4781 ALL_NON_EXITED_THREADS (thread)
4783 if (thread->executing
4784 || thread->suspend.waitstatus_pending_p)
4786 /* There were no unwaited-for children left in the target at
4787 some point, but there are now. Just ignore. */
4789 fprintf_unfiltered (gdb_stdlog,
4790 "infrun: TARGET_WAITKIND_NO_RESUMED "
4791 "(ignoring: found resumed)\n");
4792 prepare_to_wait (ecs);
4797 /* Note however that we may find no resumed thread because the whole
4798 process exited meanwhile (thus updating the thread list results
4799 in an empty thread list). In this case we know we'll be getting
4800 a process exit event shortly. */
4806 thread = any_live_thread_of_process (inf->pid);
4810 fprintf_unfiltered (gdb_stdlog,
4811 "infrun: TARGET_WAITKIND_NO_RESUMED "
4812 "(expect process exit)\n");
4813 prepare_to_wait (ecs);
4818 /* Go ahead and report the event. */
4822 /* Given an execution control state that has been freshly filled in by
4823 an event from the inferior, figure out what it means and take
4826 The alternatives are:
4828 1) stop_waiting and return; to really stop and return to the
4831 2) keep_going and return; to wait for the next event (set
4832 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4836 handle_inferior_event_1 (struct execution_control_state *ecs)
4838 enum stop_kind stop_soon;
4840 if (ecs->ws.kind == TARGET_WAITKIND_IGNORE)
4842 /* We had an event in the inferior, but we are not interested in
4843 handling it at this level. The lower layers have already
4844 done what needs to be done, if anything.
4846 One of the possible circumstances for this is when the
4847 inferior produces output for the console. The inferior has
4848 not stopped, and we are ignoring the event. Another possible
4849 circumstance is any event which the lower level knows will be
4850 reported multiple times without an intervening resume. */
4852 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n");
4853 prepare_to_wait (ecs);
4857 if (ecs->ws.kind == TARGET_WAITKIND_THREAD_EXITED)
4860 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4861 prepare_to_wait (ecs);
4865 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED
4866 && handle_no_resumed (ecs))
4869 /* Cache the last pid/waitstatus. */
4870 set_last_target_status (ecs->ptid, ecs->ws);
4872 /* Always clear state belonging to the previous time we stopped. */
4873 stop_stack_dummy = STOP_NONE;
4875 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED)
4877 /* No unwaited-for children left. IOW, all resumed children
4880 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4882 stop_print_frame = 0;
4887 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
4888 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
4890 ecs->event_thread = find_thread_ptid (ecs->ptid);
4891 /* If it's a new thread, add it to the thread database. */
4892 if (ecs->event_thread == NULL)
4893 ecs->event_thread = add_thread (ecs->ptid);
4895 /* Disable range stepping. If the next step request could use a
4896 range, this will be end up re-enabled then. */
4897 ecs->event_thread->control.may_range_step = 0;
4900 /* Dependent on valid ECS->EVENT_THREAD. */
4901 adjust_pc_after_break (ecs->event_thread, &ecs->ws);
4903 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4904 reinit_frame_cache ();
4906 breakpoint_retire_moribund ();
4908 /* First, distinguish signals caused by the debugger from signals
4909 that have to do with the program's own actions. Note that
4910 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4911 on the operating system version. Here we detect when a SIGILL or
4912 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4913 something similar for SIGSEGV, since a SIGSEGV will be generated
4914 when we're trying to execute a breakpoint instruction on a
4915 non-executable stack. This happens for call dummy breakpoints
4916 for architectures like SPARC that place call dummies on the
4918 if (ecs->ws.kind == TARGET_WAITKIND_STOPPED
4919 && (ecs->ws.value.sig == GDB_SIGNAL_ILL
4920 || ecs->ws.value.sig == GDB_SIGNAL_SEGV
4921 || ecs->ws.value.sig == GDB_SIGNAL_EMT))
4923 struct regcache *regcache = get_thread_regcache (ecs->ptid);
4925 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache),
4926 regcache_read_pc (regcache)))
4929 fprintf_unfiltered (gdb_stdlog,
4930 "infrun: Treating signal as SIGTRAP\n");
4931 ecs->ws.value.sig = GDB_SIGNAL_TRAP;
4935 /* Mark the non-executing threads accordingly. In all-stop, all
4936 threads of all processes are stopped when we get any event
4937 reported. In non-stop mode, only the event thread stops. */
4941 if (!target_is_non_stop_p ())
4942 mark_ptid = minus_one_ptid;
4943 else if (ecs->ws.kind == TARGET_WAITKIND_SIGNALLED
4944 || ecs->ws.kind == TARGET_WAITKIND_EXITED)
4946 /* If we're handling a process exit in non-stop mode, even
4947 though threads haven't been deleted yet, one would think
4948 that there is nothing to do, as threads of the dead process
4949 will be soon deleted, and threads of any other process were
4950 left running. However, on some targets, threads survive a
4951 process exit event. E.g., for the "checkpoint" command,
4952 when the current checkpoint/fork exits, linux-fork.c
4953 automatically switches to another fork from within
4954 target_mourn_inferior, by associating the same
4955 inferior/thread to another fork. We haven't mourned yet at
4956 this point, but we must mark any threads left in the
4957 process as not-executing so that finish_thread_state marks
4958 them stopped (in the user's perspective) if/when we present
4959 the stop to the user. */
4960 mark_ptid = pid_to_ptid (ptid_get_pid (ecs->ptid));
4963 mark_ptid = ecs->ptid;
4965 set_executing (mark_ptid, 0);
4967 /* Likewise the resumed flag. */
4968 set_resumed (mark_ptid, 0);
4971 switch (ecs->ws.kind)
4973 case TARGET_WAITKIND_LOADED:
4975 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n");
4976 if (!ptid_equal (ecs->ptid, inferior_ptid))
4977 context_switch (ecs->ptid);
4978 /* Ignore gracefully during startup of the inferior, as it might
4979 be the shell which has just loaded some objects, otherwise
4980 add the symbols for the newly loaded objects. Also ignore at
4981 the beginning of an attach or remote session; we will query
4982 the full list of libraries once the connection is
4985 stop_soon = get_inferior_stop_soon (ecs->ptid);
4986 if (stop_soon == NO_STOP_QUIETLY)
4988 struct regcache *regcache;
4990 regcache = get_thread_regcache (ecs->ptid);
4992 handle_solib_event ();
4994 ecs->event_thread->control.stop_bpstat
4995 = bpstat_stop_status (get_regcache_aspace (regcache),
4996 stop_pc, ecs->ptid, &ecs->ws);
4998 if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
5000 /* A catchpoint triggered. */
5001 process_event_stop_test (ecs);
5005 /* If requested, stop when the dynamic linker notifies
5006 gdb of events. This allows the user to get control
5007 and place breakpoints in initializer routines for
5008 dynamically loaded objects (among other things). */
5009 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5010 if (stop_on_solib_events)
5012 /* Make sure we print "Stopped due to solib-event" in
5014 stop_print_frame = 1;
5021 /* If we are skipping through a shell, or through shared library
5022 loading that we aren't interested in, resume the program. If
5023 we're running the program normally, also resume. */
5024 if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY)
5026 /* Loading of shared libraries might have changed breakpoint
5027 addresses. Make sure new breakpoints are inserted. */
5028 if (stop_soon == NO_STOP_QUIETLY)
5029 insert_breakpoints ();
5030 resume (GDB_SIGNAL_0);
5031 prepare_to_wait (ecs);
5035 /* But stop if we're attaching or setting up a remote
5037 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
5038 || stop_soon == STOP_QUIETLY_REMOTE)
5041 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
5046 internal_error (__FILE__, __LINE__,
5047 _("unhandled stop_soon: %d"), (int) stop_soon);
5049 case TARGET_WAITKIND_SPURIOUS:
5051 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
5052 if (!ptid_equal (ecs->ptid, inferior_ptid))
5053 context_switch (ecs->ptid);
5054 resume (GDB_SIGNAL_0);
5055 prepare_to_wait (ecs);
5058 case TARGET_WAITKIND_THREAD_CREATED:
5060 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
5061 if (!ptid_equal (ecs->ptid, inferior_ptid))
5062 context_switch (ecs->ptid);
5063 if (!switch_back_to_stepped_thread (ecs))
5067 case TARGET_WAITKIND_EXITED:
5068 case TARGET_WAITKIND_SIGNALLED:
5071 if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
5072 fprintf_unfiltered (gdb_stdlog,
5073 "infrun: TARGET_WAITKIND_EXITED\n");
5075 fprintf_unfiltered (gdb_stdlog,
5076 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5079 inferior_ptid = ecs->ptid;
5080 set_current_inferior (find_inferior_ptid (ecs->ptid));
5081 set_current_program_space (current_inferior ()->pspace);
5082 handle_vfork_child_exec_or_exit (0);
5083 target_terminal_ours (); /* Must do this before mourn anyway. */
5085 /* Clearing any previous state of convenience variables. */
5086 clear_exit_convenience_vars ();
5088 if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
5090 /* Record the exit code in the convenience variable $_exitcode, so
5091 that the user can inspect this again later. */
5092 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5093 (LONGEST) ecs->ws.value.integer);
5095 /* Also record this in the inferior itself. */
5096 current_inferior ()->has_exit_code = 1;
5097 current_inferior ()->exit_code = (LONGEST) ecs->ws.value.integer;
5099 /* Support the --return-child-result option. */
5100 return_child_result_value = ecs->ws.value.integer;
5102 observer_notify_exited (ecs->ws.value.integer);
5106 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5107 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5109 if (gdbarch_gdb_signal_to_target_p (gdbarch))
5111 /* Set the value of the internal variable $_exitsignal,
5112 which holds the signal uncaught by the inferior. */
5113 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5114 gdbarch_gdb_signal_to_target (gdbarch,
5115 ecs->ws.value.sig));
5119 /* We don't have access to the target's method used for
5120 converting between signal numbers (GDB's internal
5121 representation <-> target's representation).
5122 Therefore, we cannot do a good job at displaying this
5123 information to the user. It's better to just warn
5124 her about it (if infrun debugging is enabled), and
5127 fprintf_filtered (gdb_stdlog, _("\
5128 Cannot fill $_exitsignal with the correct signal number.\n"));
5131 observer_notify_signal_exited (ecs->ws.value.sig);
5134 gdb_flush (gdb_stdout);
5135 target_mourn_inferior ();
5136 stop_print_frame = 0;
5140 /* The following are the only cases in which we keep going;
5141 the above cases end in a continue or goto. */
5142 case TARGET_WAITKIND_FORKED:
5143 case TARGET_WAITKIND_VFORKED:
5146 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
5147 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
5149 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_VFORKED\n");
5152 /* Check whether the inferior is displaced stepping. */
5154 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5155 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5157 /* If checking displaced stepping is supported, and thread
5158 ecs->ptid is displaced stepping. */
5159 if (displaced_step_in_progress_thread (ecs->ptid))
5161 struct inferior *parent_inf
5162 = find_inferior_ptid (ecs->ptid);
5163 struct regcache *child_regcache;
5164 CORE_ADDR parent_pc;
5166 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5167 indicating that the displaced stepping of syscall instruction
5168 has been done. Perform cleanup for parent process here. Note
5169 that this operation also cleans up the child process for vfork,
5170 because their pages are shared. */
5171 displaced_step_fixup (ecs->ptid, GDB_SIGNAL_TRAP);
5172 /* Start a new step-over in another thread if there's one
5176 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
5178 struct displaced_step_inferior_state *displaced
5179 = get_displaced_stepping_state (ptid_get_pid (ecs->ptid));
5181 /* Restore scratch pad for child process. */
5182 displaced_step_restore (displaced, ecs->ws.value.related_pid);
5185 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5186 the child's PC is also within the scratchpad. Set the child's PC
5187 to the parent's PC value, which has already been fixed up.
5188 FIXME: we use the parent's aspace here, although we're touching
5189 the child, because the child hasn't been added to the inferior
5190 list yet at this point. */
5193 = get_thread_arch_aspace_regcache (ecs->ws.value.related_pid,
5195 parent_inf->aspace);
5196 /* Read PC value of parent process. */
5197 parent_pc = regcache_read_pc (regcache);
5199 if (debug_displaced)
5200 fprintf_unfiltered (gdb_stdlog,
5201 "displaced: write child pc from %s to %s\n",
5203 regcache_read_pc (child_regcache)),
5204 paddress (gdbarch, parent_pc));
5206 regcache_write_pc (child_regcache, parent_pc);
5210 if (!ptid_equal (ecs->ptid, inferior_ptid))
5211 context_switch (ecs->ptid);
5213 /* Immediately detach breakpoints from the child before there's
5214 any chance of letting the user delete breakpoints from the
5215 breakpoint lists. If we don't do this early, it's easy to
5216 leave left over traps in the child, vis: "break foo; catch
5217 fork; c; <fork>; del; c; <child calls foo>". We only follow
5218 the fork on the last `continue', and by that time the
5219 breakpoint at "foo" is long gone from the breakpoint table.
5220 If we vforked, then we don't need to unpatch here, since both
5221 parent and child are sharing the same memory pages; we'll
5222 need to unpatch at follow/detach time instead to be certain
5223 that new breakpoints added between catchpoint hit time and
5224 vfork follow are detached. */
5225 if (ecs->ws.kind != TARGET_WAITKIND_VFORKED)
5227 /* This won't actually modify the breakpoint list, but will
5228 physically remove the breakpoints from the child. */
5229 detach_breakpoints (ecs->ws.value.related_pid);
5232 delete_just_stopped_threads_single_step_breakpoints ();
5234 /* In case the event is caught by a catchpoint, remember that
5235 the event is to be followed at the next resume of the thread,
5236 and not immediately. */
5237 ecs->event_thread->pending_follow = ecs->ws;
5239 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5241 ecs->event_thread->control.stop_bpstat
5242 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5243 stop_pc, ecs->ptid, &ecs->ws);
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;
5319 /* This also takes care of reinserting breakpoints in the
5320 previously locked inferior. */
5324 case TARGET_WAITKIND_EXECD:
5326 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n");
5328 if (!ptid_equal (ecs->ptid, inferior_ptid))
5329 context_switch (ecs->ptid);
5331 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5333 /* Do whatever is necessary to the parent branch of the vfork. */
5334 handle_vfork_child_exec_or_exit (1);
5336 /* This causes the eventpoints and symbol table to be reset.
5337 Must do this now, before trying to determine whether to
5339 follow_exec (inferior_ptid, ecs->ws.value.execd_pathname);
5341 /* In follow_exec we may have deleted the original thread and
5342 created a new one. Make sure that the event thread is the
5343 execd thread for that case (this is a nop otherwise). */
5344 ecs->event_thread = inferior_thread ();
5346 ecs->event_thread->control.stop_bpstat
5347 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5348 stop_pc, ecs->ptid, &ecs->ws);
5350 /* Note that this may be referenced from inside
5351 bpstat_stop_status above, through inferior_has_execd. */
5352 xfree (ecs->ws.value.execd_pathname);
5353 ecs->ws.value.execd_pathname = NULL;
5355 /* If no catchpoint triggered for this, then keep going. */
5356 if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
5358 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5362 process_event_stop_test (ecs);
5365 /* Be careful not to try to gather much state about a thread
5366 that's in a syscall. It's frequently a losing proposition. */
5367 case TARGET_WAITKIND_SYSCALL_ENTRY:
5369 fprintf_unfiltered (gdb_stdlog,
5370 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5371 /* Getting the current syscall number. */
5372 if (handle_syscall_event (ecs) == 0)
5373 process_event_stop_test (ecs);
5376 /* Before examining the threads further, step this thread to
5377 get it entirely out of the syscall. (We get notice of the
5378 event when the thread is just on the verge of exiting a
5379 syscall. Stepping one instruction seems to get it back
5381 case TARGET_WAITKIND_SYSCALL_RETURN:
5383 fprintf_unfiltered (gdb_stdlog,
5384 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5385 if (handle_syscall_event (ecs) == 0)
5386 process_event_stop_test (ecs);
5389 case TARGET_WAITKIND_STOPPED:
5391 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n");
5392 ecs->event_thread->suspend.stop_signal = ecs->ws.value.sig;
5393 handle_signal_stop (ecs);
5396 case TARGET_WAITKIND_NO_HISTORY:
5398 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5399 /* Reverse execution: target ran out of history info. */
5401 /* Switch to the stopped thread. */
5402 if (!ptid_equal (ecs->ptid, inferior_ptid))
5403 context_switch (ecs->ptid);
5405 fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n");
5407 delete_just_stopped_threads_single_step_breakpoints ();
5408 stop_pc = regcache_read_pc (get_thread_regcache (inferior_ptid));
5409 observer_notify_no_history ();
5415 /* A wrapper around handle_inferior_event_1, which also makes sure
5416 that all temporary struct value objects that were created during
5417 the handling of the event get deleted at the end. */
5420 handle_inferior_event (struct execution_control_state *ecs)
5422 struct value *mark = value_mark ();
5424 handle_inferior_event_1 (ecs);
5425 /* Purge all temporary values created during the event handling,
5426 as it could be a long time before we return to the command level
5427 where such values would otherwise be purged. */
5428 value_free_to_mark (mark);
5431 /* Restart threads back to what they were trying to do back when we
5432 paused them for an in-line step-over. The EVENT_THREAD thread is
5436 restart_threads (struct thread_info *event_thread)
5438 struct thread_info *tp;
5440 /* In case the instruction just stepped spawned a new thread. */
5441 update_thread_list ();
5443 ALL_NON_EXITED_THREADS (tp)
5445 if (tp == event_thread)
5448 fprintf_unfiltered (gdb_stdlog,
5449 "infrun: restart threads: "
5450 "[%s] is event thread\n",
5451 target_pid_to_str (tp->ptid));
5455 if (!(tp->state == THREAD_RUNNING || tp->control.in_infcall))
5458 fprintf_unfiltered (gdb_stdlog,
5459 "infrun: restart threads: "
5460 "[%s] not meant to be running\n",
5461 target_pid_to_str (tp->ptid));
5468 fprintf_unfiltered (gdb_stdlog,
5469 "infrun: restart threads: [%s] resumed\n",
5470 target_pid_to_str (tp->ptid));
5471 gdb_assert (tp->executing || tp->suspend.waitstatus_pending_p);
5475 if (thread_is_in_step_over_chain (tp))
5478 fprintf_unfiltered (gdb_stdlog,
5479 "infrun: restart threads: "
5480 "[%s] needs step-over\n",
5481 target_pid_to_str (tp->ptid));
5482 gdb_assert (!tp->resumed);
5487 if (tp->suspend.waitstatus_pending_p)
5490 fprintf_unfiltered (gdb_stdlog,
5491 "infrun: restart threads: "
5492 "[%s] has pending status\n",
5493 target_pid_to_str (tp->ptid));
5498 /* If some thread needs to start a step-over at this point, it
5499 should still be in the step-over queue, and thus skipped
5501 if (thread_still_needs_step_over (tp))
5503 internal_error (__FILE__, __LINE__,
5504 "thread [%s] needs a step-over, but not in "
5505 "step-over queue\n",
5506 target_pid_to_str (tp->ptid));
5509 if (currently_stepping (tp))
5512 fprintf_unfiltered (gdb_stdlog,
5513 "infrun: restart threads: [%s] was stepping\n",
5514 target_pid_to_str (tp->ptid));
5515 keep_going_stepped_thread (tp);
5519 struct execution_control_state ecss;
5520 struct execution_control_state *ecs = &ecss;
5523 fprintf_unfiltered (gdb_stdlog,
5524 "infrun: restart threads: [%s] continuing\n",
5525 target_pid_to_str (tp->ptid));
5526 reset_ecs (ecs, tp);
5527 switch_to_thread (tp->ptid);
5528 keep_going_pass_signal (ecs);
5533 /* Callback for iterate_over_threads. Find a resumed thread that has
5534 a pending waitstatus. */
5537 resumed_thread_with_pending_status (struct thread_info *tp,
5541 && tp->suspend.waitstatus_pending_p);
5544 /* Called when we get an event that may finish an in-line or
5545 out-of-line (displaced stepping) step-over started previously.
5546 Return true if the event is processed and we should go back to the
5547 event loop; false if the caller should continue processing the
5551 finish_step_over (struct execution_control_state *ecs)
5553 int had_step_over_info;
5555 displaced_step_fixup (ecs->ptid,
5556 ecs->event_thread->suspend.stop_signal);
5558 had_step_over_info = step_over_info_valid_p ();
5560 if (had_step_over_info)
5562 /* If we're stepping over a breakpoint with all threads locked,
5563 then only the thread that was stepped should be reporting
5565 gdb_assert (ecs->event_thread->control.trap_expected);
5567 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
5568 clear_step_over_info ();
5571 if (!target_is_non_stop_p ())
5574 /* Start a new step-over in another thread if there's one that
5578 /* If we were stepping over a breakpoint before, and haven't started
5579 a new in-line step-over sequence, then restart all other threads
5580 (except the event thread). We can't do this in all-stop, as then
5581 e.g., we wouldn't be able to issue any other remote packet until
5582 these other threads stop. */
5583 if (had_step_over_info && !step_over_info_valid_p ())
5585 struct thread_info *pending;
5587 /* If we only have threads with pending statuses, the restart
5588 below won't restart any thread and so nothing re-inserts the
5589 breakpoint we just stepped over. But we need it inserted
5590 when we later process the pending events, otherwise if
5591 another thread has a pending event for this breakpoint too,
5592 we'd discard its event (because the breakpoint that
5593 originally caused the event was no longer inserted). */
5594 context_switch (ecs->ptid);
5595 insert_breakpoints ();
5597 restart_threads (ecs->event_thread);
5599 /* If we have events pending, go through handle_inferior_event
5600 again, picking up a pending event at random. This avoids
5601 thread starvation. */
5603 /* But not if we just stepped over a watchpoint in order to let
5604 the instruction execute so we can evaluate its expression.
5605 The set of watchpoints that triggered is recorded in the
5606 breakpoint objects themselves (see bp->watchpoint_triggered).
5607 If we processed another event first, that other event could
5608 clobber this info. */
5609 if (ecs->event_thread->stepping_over_watchpoint)
5612 pending = iterate_over_threads (resumed_thread_with_pending_status,
5614 if (pending != NULL)
5616 struct thread_info *tp = ecs->event_thread;
5617 struct regcache *regcache;
5621 fprintf_unfiltered (gdb_stdlog,
5622 "infrun: found resumed threads with "
5623 "pending events, saving status\n");
5626 gdb_assert (pending != tp);
5628 /* Record the event thread's event for later. */
5629 save_waitstatus (tp, &ecs->ws);
5630 /* This was cleared early, by handle_inferior_event. Set it
5631 so this pending event is considered by
5635 gdb_assert (!tp->executing);
5637 regcache = get_thread_regcache (tp->ptid);
5638 tp->suspend.stop_pc = regcache_read_pc (regcache);
5642 fprintf_unfiltered (gdb_stdlog,
5643 "infrun: saved stop_pc=%s for %s "
5644 "(currently_stepping=%d)\n",
5645 paddress (target_gdbarch (),
5646 tp->suspend.stop_pc),
5647 target_pid_to_str (tp->ptid),
5648 currently_stepping (tp));
5651 /* This in-line step-over finished; clear this so we won't
5652 start a new one. This is what handle_signal_stop would
5653 do, if we returned false. */
5654 tp->stepping_over_breakpoint = 0;
5656 /* Wake up the event loop again. */
5657 mark_async_event_handler (infrun_async_inferior_event_token);
5659 prepare_to_wait (ecs);
5667 /* Come here when the program has stopped with a signal. */
5670 handle_signal_stop (struct execution_control_state *ecs)
5672 struct frame_info *frame;
5673 struct gdbarch *gdbarch;
5674 int stopped_by_watchpoint;
5675 enum stop_kind stop_soon;
5678 gdb_assert (ecs->ws.kind == TARGET_WAITKIND_STOPPED);
5680 /* Do we need to clean up the state of a thread that has
5681 completed a displaced single-step? (Doing so usually affects
5682 the PC, so do it here, before we set stop_pc.) */
5683 if (finish_step_over (ecs))
5686 /* If we either finished a single-step or hit a breakpoint, but
5687 the user wanted this thread to be stopped, pretend we got a
5688 SIG0 (generic unsignaled stop). */
5689 if (ecs->event_thread->stop_requested
5690 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
5691 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5693 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5697 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5698 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5699 struct cleanup *old_chain = save_inferior_ptid ();
5701 inferior_ptid = ecs->ptid;
5703 fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = %s\n",
5704 paddress (gdbarch, stop_pc));
5705 if (target_stopped_by_watchpoint ())
5709 fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n");
5711 if (target_stopped_data_address (¤t_target, &addr))
5712 fprintf_unfiltered (gdb_stdlog,
5713 "infrun: stopped data address = %s\n",
5714 paddress (gdbarch, addr));
5716 fprintf_unfiltered (gdb_stdlog,
5717 "infrun: (no data address available)\n");
5720 do_cleanups (old_chain);
5723 /* This is originated from start_remote(), start_inferior() and
5724 shared libraries hook functions. */
5725 stop_soon = get_inferior_stop_soon (ecs->ptid);
5726 if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE)
5728 if (!ptid_equal (ecs->ptid, inferior_ptid))
5729 context_switch (ecs->ptid);
5731 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
5732 stop_print_frame = 1;
5737 /* This originates from attach_command(). We need to overwrite
5738 the stop_signal here, because some kernels don't ignore a
5739 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5740 See more comments in inferior.h. On the other hand, if we
5741 get a non-SIGSTOP, report it to the user - assume the backend
5742 will handle the SIGSTOP if it should show up later.
5744 Also consider that the attach is complete when we see a
5745 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5746 target extended-remote report it instead of a SIGSTOP
5747 (e.g. gdbserver). We already rely on SIGTRAP being our
5748 signal, so this is no exception.
5750 Also consider that the attach is complete when we see a
5751 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5752 the target to stop all threads of the inferior, in case the
5753 low level attach operation doesn't stop them implicitly. If
5754 they weren't stopped implicitly, then the stub will report a
5755 GDB_SIGNAL_0, meaning: stopped for no particular reason
5756 other than GDB's request. */
5757 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
5758 && (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_STOP
5759 || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5760 || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_0))
5762 stop_print_frame = 1;
5764 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5768 /* See if something interesting happened to the non-current thread. If
5769 so, then switch to that thread. */
5770 if (!ptid_equal (ecs->ptid, inferior_ptid))
5773 fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n");
5775 context_switch (ecs->ptid);
5777 if (deprecated_context_hook)
5778 deprecated_context_hook (ptid_to_global_thread_id (ecs->ptid));
5781 /* At this point, get hold of the now-current thread's frame. */
5782 frame = get_current_frame ();
5783 gdbarch = get_frame_arch (frame);
5785 /* Pull the single step breakpoints out of the target. */
5786 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
5788 struct regcache *regcache;
5789 struct address_space *aspace;
5792 regcache = get_thread_regcache (ecs->ptid);
5793 aspace = get_regcache_aspace (regcache);
5794 pc = regcache_read_pc (regcache);
5796 /* However, before doing so, if this single-step breakpoint was
5797 actually for another thread, set this thread up for moving
5799 if (!thread_has_single_step_breakpoint_here (ecs->event_thread,
5802 if (single_step_breakpoint_inserted_here_p (aspace, pc))
5806 fprintf_unfiltered (gdb_stdlog,
5807 "infrun: [%s] hit another thread's "
5808 "single-step breakpoint\n",
5809 target_pid_to_str (ecs->ptid));
5811 ecs->hit_singlestep_breakpoint = 1;
5818 fprintf_unfiltered (gdb_stdlog,
5819 "infrun: [%s] hit its "
5820 "single-step breakpoint\n",
5821 target_pid_to_str (ecs->ptid));
5825 delete_just_stopped_threads_single_step_breakpoints ();
5827 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5828 && ecs->event_thread->control.trap_expected
5829 && ecs->event_thread->stepping_over_watchpoint)
5830 stopped_by_watchpoint = 0;
5832 stopped_by_watchpoint = watchpoints_triggered (&ecs->ws);
5834 /* If necessary, step over this watchpoint. We'll be back to display
5836 if (stopped_by_watchpoint
5837 && (target_have_steppable_watchpoint
5838 || gdbarch_have_nonsteppable_watchpoint (gdbarch)))
5840 /* At this point, we are stopped at an instruction which has
5841 attempted to write to a piece of memory under control of
5842 a watchpoint. The instruction hasn't actually executed
5843 yet. If we were to evaluate the watchpoint expression
5844 now, we would get the old value, and therefore no change
5845 would seem to have occurred.
5847 In order to make watchpoints work `right', we really need
5848 to complete the memory write, and then evaluate the
5849 watchpoint expression. We do this by single-stepping the
5852 It may not be necessary to disable the watchpoint to step over
5853 it. For example, the PA can (with some kernel cooperation)
5854 single step over a watchpoint without disabling the watchpoint.
5856 It is far more common to need to disable a watchpoint to step
5857 the inferior over it. If we have non-steppable watchpoints,
5858 we must disable the current watchpoint; it's simplest to
5859 disable all watchpoints.
5861 Any breakpoint at PC must also be stepped over -- if there's
5862 one, it will have already triggered before the watchpoint
5863 triggered, and we either already reported it to the user, or
5864 it didn't cause a stop and we called keep_going. In either
5865 case, if there was a breakpoint at PC, we must be trying to
5867 ecs->event_thread->stepping_over_watchpoint = 1;
5872 ecs->event_thread->stepping_over_breakpoint = 0;
5873 ecs->event_thread->stepping_over_watchpoint = 0;
5874 bpstat_clear (&ecs->event_thread->control.stop_bpstat);
5875 ecs->event_thread->control.stop_step = 0;
5876 stop_print_frame = 1;
5877 stopped_by_random_signal = 0;
5879 /* Hide inlined functions starting here, unless we just performed stepi or
5880 nexti. After stepi and nexti, always show the innermost frame (not any
5881 inline function call sites). */
5882 if (ecs->event_thread->control.step_range_end != 1)
5884 struct address_space *aspace =
5885 get_regcache_aspace (get_thread_regcache (ecs->ptid));
5887 /* skip_inline_frames is expensive, so we avoid it if we can
5888 determine that the address is one where functions cannot have
5889 been inlined. This improves performance with inferiors that
5890 load a lot of shared libraries, because the solib event
5891 breakpoint is defined as the address of a function (i.e. not
5892 inline). Note that we have to check the previous PC as well
5893 as the current one to catch cases when we have just
5894 single-stepped off a breakpoint prior to reinstating it.
5895 Note that we're assuming that the code we single-step to is
5896 not inline, but that's not definitive: there's nothing
5897 preventing the event breakpoint function from containing
5898 inlined code, and the single-step ending up there. If the
5899 user had set a breakpoint on that inlined code, the missing
5900 skip_inline_frames call would break things. Fortunately
5901 that's an extremely unlikely scenario. */
5902 if (!pc_at_non_inline_function (aspace, stop_pc, &ecs->ws)
5903 && !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5904 && ecs->event_thread->control.trap_expected
5905 && pc_at_non_inline_function (aspace,
5906 ecs->event_thread->prev_pc,
5909 skip_inline_frames (ecs->ptid);
5911 /* Re-fetch current thread's frame in case that invalidated
5913 frame = get_current_frame ();
5914 gdbarch = get_frame_arch (frame);
5918 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5919 && ecs->event_thread->control.trap_expected
5920 && gdbarch_single_step_through_delay_p (gdbarch)
5921 && currently_stepping (ecs->event_thread))
5923 /* We're trying to step off a breakpoint. Turns out that we're
5924 also on an instruction that needs to be stepped multiple
5925 times before it's been fully executing. E.g., architectures
5926 with a delay slot. It needs to be stepped twice, once for
5927 the instruction and once for the delay slot. */
5928 int step_through_delay
5929 = gdbarch_single_step_through_delay (gdbarch, frame);
5931 if (debug_infrun && step_through_delay)
5932 fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n");
5933 if (ecs->event_thread->control.step_range_end == 0
5934 && step_through_delay)
5936 /* The user issued a continue when stopped at a breakpoint.
5937 Set up for another trap and get out of here. */
5938 ecs->event_thread->stepping_over_breakpoint = 1;
5942 else if (step_through_delay)
5944 /* The user issued a step when stopped at a breakpoint.
5945 Maybe we should stop, maybe we should not - the delay
5946 slot *might* correspond to a line of source. In any
5947 case, don't decide that here, just set
5948 ecs->stepping_over_breakpoint, making sure we
5949 single-step again before breakpoints are re-inserted. */
5950 ecs->event_thread->stepping_over_breakpoint = 1;
5954 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5955 handles this event. */
5956 ecs->event_thread->control.stop_bpstat
5957 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5958 stop_pc, ecs->ptid, &ecs->ws);
5960 /* Following in case break condition called a
5962 stop_print_frame = 1;
5964 /* This is where we handle "moribund" watchpoints. Unlike
5965 software breakpoints traps, hardware watchpoint traps are
5966 always distinguishable from random traps. If no high-level
5967 watchpoint is associated with the reported stop data address
5968 anymore, then the bpstat does not explain the signal ---
5969 simply make sure to ignore it if `stopped_by_watchpoint' is
5973 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5974 && !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
5976 && stopped_by_watchpoint)
5977 fprintf_unfiltered (gdb_stdlog,
5978 "infrun: no user watchpoint explains "
5979 "watchpoint SIGTRAP, ignoring\n");
5981 /* NOTE: cagney/2003-03-29: These checks for a random signal
5982 at one stage in the past included checks for an inferior
5983 function call's call dummy's return breakpoint. The original
5984 comment, that went with the test, read:
5986 ``End of a stack dummy. Some systems (e.g. Sony news) give
5987 another signal besides SIGTRAP, so check here as well as
5990 If someone ever tries to get call dummys on a
5991 non-executable stack to work (where the target would stop
5992 with something like a SIGSEGV), then those tests might need
5993 to be re-instated. Given, however, that the tests were only
5994 enabled when momentary breakpoints were not being used, I
5995 suspect that it won't be the case.
5997 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5998 be necessary for call dummies on a non-executable stack on
6001 /* See if the breakpoints module can explain the signal. */
6003 = !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
6004 ecs->event_thread->suspend.stop_signal);
6006 /* Maybe this was a trap for a software breakpoint that has since
6008 if (random_signal && target_stopped_by_sw_breakpoint ())
6010 if (program_breakpoint_here_p (gdbarch, stop_pc))
6012 struct regcache *regcache;
6015 /* Re-adjust PC to what the program would see if GDB was not
6017 regcache = get_thread_regcache (ecs->event_thread->ptid);
6018 decr_pc = gdbarch_decr_pc_after_break (gdbarch);
6021 struct cleanup *old_cleanups = make_cleanup (null_cleanup, NULL);
6023 if (record_full_is_used ())
6024 record_full_gdb_operation_disable_set ();
6026 regcache_write_pc (regcache, stop_pc + decr_pc);
6028 do_cleanups (old_cleanups);
6033 /* A delayed software breakpoint event. Ignore the trap. */
6035 fprintf_unfiltered (gdb_stdlog,
6036 "infrun: delayed software breakpoint "
6037 "trap, ignoring\n");
6042 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6043 has since been removed. */
6044 if (random_signal && target_stopped_by_hw_breakpoint ())
6046 /* A delayed hardware breakpoint event. Ignore the trap. */
6048 fprintf_unfiltered (gdb_stdlog,
6049 "infrun: delayed hardware breakpoint/watchpoint "
6050 "trap, ignoring\n");
6054 /* If not, perhaps stepping/nexting can. */
6056 random_signal = !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
6057 && currently_stepping (ecs->event_thread));
6059 /* Perhaps the thread hit a single-step breakpoint of _another_
6060 thread. Single-step breakpoints are transparent to the
6061 breakpoints module. */
6063 random_signal = !ecs->hit_singlestep_breakpoint;
6065 /* No? Perhaps we got a moribund watchpoint. */
6067 random_signal = !stopped_by_watchpoint;
6069 /* For the program's own signals, act according to
6070 the signal handling tables. */
6074 /* Signal not for debugging purposes. */
6075 struct inferior *inf = find_inferior_ptid (ecs->ptid);
6076 enum gdb_signal stop_signal = ecs->event_thread->suspend.stop_signal;
6079 fprintf_unfiltered (gdb_stdlog, "infrun: random signal (%s)\n",
6080 gdb_signal_to_symbol_string (stop_signal));
6082 stopped_by_random_signal = 1;
6084 /* Always stop on signals if we're either just gaining control
6085 of the program, or the user explicitly requested this thread
6086 to remain stopped. */
6087 if (stop_soon != NO_STOP_QUIETLY
6088 || ecs->event_thread->stop_requested
6090 && signal_stop_state (ecs->event_thread->suspend.stop_signal)))
6096 /* Notify observers the signal has "handle print" set. Note we
6097 returned early above if stopping; normal_stop handles the
6098 printing in that case. */
6099 if (signal_print[ecs->event_thread->suspend.stop_signal])
6101 /* The signal table tells us to print about this signal. */
6102 target_terminal_ours_for_output ();
6103 observer_notify_signal_received (ecs->event_thread->suspend.stop_signal);
6104 target_terminal_inferior ();
6107 /* Clear the signal if it should not be passed. */
6108 if (signal_program[ecs->event_thread->suspend.stop_signal] == 0)
6109 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
6111 if (ecs->event_thread->prev_pc == stop_pc
6112 && ecs->event_thread->control.trap_expected
6113 && ecs->event_thread->control.step_resume_breakpoint == NULL)
6117 /* We were just starting a new sequence, attempting to
6118 single-step off of a breakpoint and expecting a SIGTRAP.
6119 Instead this signal arrives. This signal will take us out
6120 of the stepping range so GDB needs to remember to, when
6121 the signal handler returns, resume stepping off that
6123 /* To simplify things, "continue" is forced to use the same
6124 code paths as single-step - set a breakpoint at the
6125 signal return address and then, once hit, step off that
6128 fprintf_unfiltered (gdb_stdlog,
6129 "infrun: signal arrived while stepping over "
6132 was_in_line = step_over_info_valid_p ();
6133 clear_step_over_info ();
6134 insert_hp_step_resume_breakpoint_at_frame (frame);
6135 ecs->event_thread->step_after_step_resume_breakpoint = 1;
6136 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6137 ecs->event_thread->control.trap_expected = 0;
6139 if (target_is_non_stop_p ())
6141 /* Either "set non-stop" is "on", or the target is
6142 always in non-stop mode. In this case, we have a bit
6143 more work to do. Resume the current thread, and if
6144 we had paused all threads, restart them while the
6145 signal handler runs. */
6150 restart_threads (ecs->event_thread);
6152 else if (debug_infrun)
6154 fprintf_unfiltered (gdb_stdlog,
6155 "infrun: no need to restart threads\n");
6160 /* If we were nexting/stepping some other thread, switch to
6161 it, so that we don't continue it, losing control. */
6162 if (!switch_back_to_stepped_thread (ecs))
6167 if (ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_0
6168 && (pc_in_thread_step_range (stop_pc, ecs->event_thread)
6169 || ecs->event_thread->control.step_range_end == 1)
6170 && frame_id_eq (get_stack_frame_id (frame),
6171 ecs->event_thread->control.step_stack_frame_id)
6172 && ecs->event_thread->control.step_resume_breakpoint == NULL)
6174 /* The inferior is about to take a signal that will take it
6175 out of the single step range. Set a breakpoint at the
6176 current PC (which is presumably where the signal handler
6177 will eventually return) and then allow the inferior to
6180 Note that this is only needed for a signal delivered
6181 while in the single-step range. Nested signals aren't a
6182 problem as they eventually all return. */
6184 fprintf_unfiltered (gdb_stdlog,
6185 "infrun: signal may take us out of "
6186 "single-step range\n");
6188 clear_step_over_info ();
6189 insert_hp_step_resume_breakpoint_at_frame (frame);
6190 ecs->event_thread->step_after_step_resume_breakpoint = 1;
6191 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6192 ecs->event_thread->control.trap_expected = 0;
6197 /* Note: step_resume_breakpoint may be non-NULL. This occures
6198 when either there's a nested signal, or when there's a
6199 pending signal enabled just as the signal handler returns
6200 (leaving the inferior at the step-resume-breakpoint without
6201 actually executing it). Either way continue until the
6202 breakpoint is really hit. */
6204 if (!switch_back_to_stepped_thread (ecs))
6207 fprintf_unfiltered (gdb_stdlog,
6208 "infrun: random signal, keep going\n");
6215 process_event_stop_test (ecs);
6218 /* Come here when we've got some debug event / signal we can explain
6219 (IOW, not a random signal), and test whether it should cause a
6220 stop, or whether we should resume the inferior (transparently).
6221 E.g., could be a breakpoint whose condition evaluates false; we
6222 could be still stepping within the line; etc. */
6225 process_event_stop_test (struct execution_control_state *ecs)
6227 struct symtab_and_line stop_pc_sal;
6228 struct frame_info *frame;
6229 struct gdbarch *gdbarch;
6230 CORE_ADDR jmp_buf_pc;
6231 struct bpstat_what what;
6233 /* Handle cases caused by hitting a breakpoint. */
6235 frame = get_current_frame ();
6236 gdbarch = get_frame_arch (frame);
6238 what = bpstat_what (ecs->event_thread->control.stop_bpstat);
6240 if (what.call_dummy)
6242 stop_stack_dummy = what.call_dummy;
6245 /* A few breakpoint types have callbacks associated (e.g.,
6246 bp_jit_event). Run them now. */
6247 bpstat_run_callbacks (ecs->event_thread->control.stop_bpstat);
6249 /* If we hit an internal event that triggers symbol changes, the
6250 current frame will be invalidated within bpstat_what (e.g., if we
6251 hit an internal solib event). Re-fetch it. */
6252 frame = get_current_frame ();
6253 gdbarch = get_frame_arch (frame);
6255 switch (what.main_action)
6257 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
6258 /* If we hit the breakpoint at longjmp while stepping, we
6259 install a momentary breakpoint at the target of the
6263 fprintf_unfiltered (gdb_stdlog,
6264 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6266 ecs->event_thread->stepping_over_breakpoint = 1;
6268 if (what.is_longjmp)
6270 struct value *arg_value;
6272 /* If we set the longjmp breakpoint via a SystemTap probe,
6273 then use it to extract the arguments. The destination PC
6274 is the third argument to the probe. */
6275 arg_value = probe_safe_evaluate_at_pc (frame, 2);
6278 jmp_buf_pc = value_as_address (arg_value);
6279 jmp_buf_pc = gdbarch_addr_bits_remove (gdbarch, jmp_buf_pc);
6281 else if (!gdbarch_get_longjmp_target_p (gdbarch)
6282 || !gdbarch_get_longjmp_target (gdbarch,
6283 frame, &jmp_buf_pc))
6286 fprintf_unfiltered (gdb_stdlog,
6287 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6288 "(!gdbarch_get_longjmp_target)\n");
6293 /* Insert a breakpoint at resume address. */
6294 insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc);
6297 check_exception_resume (ecs, frame);
6301 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
6303 struct frame_info *init_frame;
6305 /* There are several cases to consider.
6307 1. The initiating frame no longer exists. In this case we
6308 must stop, because the exception or longjmp has gone too
6311 2. The initiating frame exists, and is the same as the
6312 current frame. We stop, because the exception or longjmp
6315 3. The initiating frame exists and is different from the
6316 current frame. This means the exception or longjmp has
6317 been caught beneath the initiating frame, so keep going.
6319 4. longjmp breakpoint has been placed just to protect
6320 against stale dummy frames and user is not interested in
6321 stopping around longjmps. */
6324 fprintf_unfiltered (gdb_stdlog,
6325 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6327 gdb_assert (ecs->event_thread->control.exception_resume_breakpoint
6329 delete_exception_resume_breakpoint (ecs->event_thread);
6331 if (what.is_longjmp)
6333 check_longjmp_breakpoint_for_call_dummy (ecs->event_thread);
6335 if (!frame_id_p (ecs->event_thread->initiating_frame))
6343 init_frame = frame_find_by_id (ecs->event_thread->initiating_frame);
6347 struct frame_id current_id
6348 = get_frame_id (get_current_frame ());
6349 if (frame_id_eq (current_id,
6350 ecs->event_thread->initiating_frame))
6352 /* Case 2. Fall through. */
6362 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6364 delete_step_resume_breakpoint (ecs->event_thread);
6366 end_stepping_range (ecs);
6370 case BPSTAT_WHAT_SINGLE:
6372 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
6373 ecs->event_thread->stepping_over_breakpoint = 1;
6374 /* Still need to check other stuff, at least the case where we
6375 are stepping and step out of the right range. */
6378 case BPSTAT_WHAT_STEP_RESUME:
6380 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6382 delete_step_resume_breakpoint (ecs->event_thread);
6383 if (ecs->event_thread->control.proceed_to_finish
6384 && execution_direction == EXEC_REVERSE)
6386 struct thread_info *tp = ecs->event_thread;
6388 /* We are finishing a function in reverse, and just hit the
6389 step-resume breakpoint at the start address of the
6390 function, and we're almost there -- just need to back up
6391 by one more single-step, which should take us back to the
6393 tp->control.step_range_start = tp->control.step_range_end = 1;
6397 fill_in_stop_func (gdbarch, ecs);
6398 if (stop_pc == ecs->stop_func_start
6399 && execution_direction == EXEC_REVERSE)
6401 /* We are stepping over a function call in reverse, and just
6402 hit the step-resume breakpoint at the start address of
6403 the function. Go back to single-stepping, which should
6404 take us back to the function call. */
6405 ecs->event_thread->stepping_over_breakpoint = 1;
6411 case BPSTAT_WHAT_STOP_NOISY:
6413 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6414 stop_print_frame = 1;
6416 /* Assume the thread stopped for a breapoint. We'll still check
6417 whether a/the breakpoint is there when the thread is next
6419 ecs->event_thread->stepping_over_breakpoint = 1;
6424 case BPSTAT_WHAT_STOP_SILENT:
6426 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6427 stop_print_frame = 0;
6429 /* Assume the thread stopped for a breapoint. We'll still check
6430 whether a/the breakpoint is there when the thread is next
6432 ecs->event_thread->stepping_over_breakpoint = 1;
6436 case BPSTAT_WHAT_HP_STEP_RESUME:
6438 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6440 delete_step_resume_breakpoint (ecs->event_thread);
6441 if (ecs->event_thread->step_after_step_resume_breakpoint)
6443 /* Back when the step-resume breakpoint was inserted, we
6444 were trying to single-step off a breakpoint. Go back to
6446 ecs->event_thread->step_after_step_resume_breakpoint = 0;
6447 ecs->event_thread->stepping_over_breakpoint = 1;
6453 case BPSTAT_WHAT_KEEP_CHECKING:
6457 /* If we stepped a permanent breakpoint and we had a high priority
6458 step-resume breakpoint for the address we stepped, but we didn't
6459 hit it, then we must have stepped into the signal handler. The
6460 step-resume was only necessary to catch the case of _not_
6461 stepping into the handler, so delete it, and fall through to
6462 checking whether the step finished. */
6463 if (ecs->event_thread->stepped_breakpoint)
6465 struct breakpoint *sr_bp
6466 = ecs->event_thread->control.step_resume_breakpoint;
6469 && sr_bp->loc->permanent
6470 && sr_bp->type == bp_hp_step_resume
6471 && sr_bp->loc->address == ecs->event_thread->prev_pc)
6474 fprintf_unfiltered (gdb_stdlog,
6475 "infrun: stepped permanent breakpoint, stopped in "
6477 delete_step_resume_breakpoint (ecs->event_thread);
6478 ecs->event_thread->step_after_step_resume_breakpoint = 0;
6482 /* We come here if we hit a breakpoint but should not stop for it.
6483 Possibly we also were stepping and should stop for that. So fall
6484 through and test for stepping. But, if not stepping, do not
6487 /* In all-stop mode, if we're currently stepping but have stopped in
6488 some other thread, we need to switch back to the stepped thread. */
6489 if (switch_back_to_stepped_thread (ecs))
6492 if (ecs->event_thread->control.step_resume_breakpoint)
6495 fprintf_unfiltered (gdb_stdlog,
6496 "infrun: step-resume breakpoint is inserted\n");
6498 /* Having a step-resume breakpoint overrides anything
6499 else having to do with stepping commands until
6500 that breakpoint is reached. */
6505 if (ecs->event_thread->control.step_range_end == 0)
6508 fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n");
6509 /* Likewise if we aren't even stepping. */
6514 /* Re-fetch current thread's frame in case the code above caused
6515 the frame cache to be re-initialized, making our FRAME variable
6516 a dangling pointer. */
6517 frame = get_current_frame ();
6518 gdbarch = get_frame_arch (frame);
6519 fill_in_stop_func (gdbarch, ecs);
6521 /* If stepping through a line, keep going if still within it.
6523 Note that step_range_end is the address of the first instruction
6524 beyond the step range, and NOT the address of the last instruction
6527 Note also that during reverse execution, we may be stepping
6528 through a function epilogue and therefore must detect when
6529 the current-frame changes in the middle of a line. */
6531 if (pc_in_thread_step_range (stop_pc, ecs->event_thread)
6532 && (execution_direction != EXEC_REVERSE
6533 || frame_id_eq (get_frame_id (frame),
6534 ecs->event_thread->control.step_frame_id)))
6538 (gdb_stdlog, "infrun: stepping inside range [%s-%s]\n",
6539 paddress (gdbarch, ecs->event_thread->control.step_range_start),
6540 paddress (gdbarch, ecs->event_thread->control.step_range_end));
6542 /* Tentatively re-enable range stepping; `resume' disables it if
6543 necessary (e.g., if we're stepping over a breakpoint or we
6544 have software watchpoints). */
6545 ecs->event_thread->control.may_range_step = 1;
6547 /* When stepping backward, stop at beginning of line range
6548 (unless it's the function entry point, in which case
6549 keep going back to the call point). */
6550 if (stop_pc == ecs->event_thread->control.step_range_start
6551 && stop_pc != ecs->stop_func_start
6552 && execution_direction == EXEC_REVERSE)
6553 end_stepping_range (ecs);
6560 /* We stepped out of the stepping range. */
6562 /* If we are stepping at the source level and entered the runtime
6563 loader dynamic symbol resolution code...
6565 EXEC_FORWARD: we keep on single stepping until we exit the run
6566 time loader code and reach the callee's address.
6568 EXEC_REVERSE: we've already executed the callee (backward), and
6569 the runtime loader code is handled just like any other
6570 undebuggable function call. Now we need only keep stepping
6571 backward through the trampoline code, and that's handled further
6572 down, so there is nothing for us to do here. */
6574 if (execution_direction != EXEC_REVERSE
6575 && ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6576 && in_solib_dynsym_resolve_code (stop_pc))
6578 CORE_ADDR pc_after_resolver =
6579 gdbarch_skip_solib_resolver (gdbarch, stop_pc);
6582 fprintf_unfiltered (gdb_stdlog,
6583 "infrun: stepped into dynsym resolve code\n");
6585 if (pc_after_resolver)
6587 /* Set up a step-resume breakpoint at the address
6588 indicated by SKIP_SOLIB_RESOLVER. */
6589 struct symtab_and_line sr_sal;
6592 sr_sal.pc = pc_after_resolver;
6593 sr_sal.pspace = get_frame_program_space (frame);
6595 insert_step_resume_breakpoint_at_sal (gdbarch,
6596 sr_sal, null_frame_id);
6603 if (ecs->event_thread->control.step_range_end != 1
6604 && (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6605 || ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
6606 && get_frame_type (frame) == SIGTRAMP_FRAME)
6609 fprintf_unfiltered (gdb_stdlog,
6610 "infrun: stepped into signal trampoline\n");
6611 /* The inferior, while doing a "step" or "next", has ended up in
6612 a signal trampoline (either by a signal being delivered or by
6613 the signal handler returning). Just single-step until the
6614 inferior leaves the trampoline (either by calling the handler
6620 /* If we're in the return path from a shared library trampoline,
6621 we want to proceed through the trampoline when stepping. */
6622 /* macro/2012-04-25: This needs to come before the subroutine
6623 call check below as on some targets return trampolines look
6624 like subroutine calls (MIPS16 return thunks). */
6625 if (gdbarch_in_solib_return_trampoline (gdbarch,
6626 stop_pc, ecs->stop_func_name)
6627 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
6629 /* Determine where this trampoline returns. */
6630 CORE_ADDR real_stop_pc;
6632 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
6635 fprintf_unfiltered (gdb_stdlog,
6636 "infrun: stepped into solib return tramp\n");
6638 /* Only proceed through if we know where it's going. */
6641 /* And put the step-breakpoint there and go until there. */
6642 struct symtab_and_line sr_sal;
6644 init_sal (&sr_sal); /* initialize to zeroes */
6645 sr_sal.pc = real_stop_pc;
6646 sr_sal.section = find_pc_overlay (sr_sal.pc);
6647 sr_sal.pspace = get_frame_program_space (frame);
6649 /* Do not specify what the fp should be when we stop since
6650 on some machines the prologue is where the new fp value
6652 insert_step_resume_breakpoint_at_sal (gdbarch,
6653 sr_sal, null_frame_id);
6655 /* Restart without fiddling with the step ranges or
6662 /* Check for subroutine calls. The check for the current frame
6663 equalling the step ID is not necessary - the check of the
6664 previous frame's ID is sufficient - but it is a common case and
6665 cheaper than checking the previous frame's ID.
6667 NOTE: frame_id_eq will never report two invalid frame IDs as
6668 being equal, so to get into this block, both the current and
6669 previous frame must have valid frame IDs. */
6670 /* The outer_frame_id check is a heuristic to detect stepping
6671 through startup code. If we step over an instruction which
6672 sets the stack pointer from an invalid value to a valid value,
6673 we may detect that as a subroutine call from the mythical
6674 "outermost" function. This could be fixed by marking
6675 outermost frames as !stack_p,code_p,special_p. Then the
6676 initial outermost frame, before sp was valid, would
6677 have code_addr == &_start. See the comment in frame_id_eq
6679 if (!frame_id_eq (get_stack_frame_id (frame),
6680 ecs->event_thread->control.step_stack_frame_id)
6681 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6682 ecs->event_thread->control.step_stack_frame_id)
6683 && (!frame_id_eq (ecs->event_thread->control.step_stack_frame_id,
6685 || (ecs->event_thread->control.step_start_function
6686 != find_pc_function (stop_pc)))))
6688 CORE_ADDR real_stop_pc;
6691 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n");
6693 if (ecs->event_thread->control.step_over_calls == STEP_OVER_NONE)
6695 /* I presume that step_over_calls is only 0 when we're
6696 supposed to be stepping at the assembly language level
6697 ("stepi"). Just stop. */
6698 /* And this works the same backward as frontward. MVS */
6699 end_stepping_range (ecs);
6703 /* Reverse stepping through solib trampolines. */
6705 if (execution_direction == EXEC_REVERSE
6706 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE
6707 && (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
6708 || (ecs->stop_func_start == 0
6709 && in_solib_dynsym_resolve_code (stop_pc))))
6711 /* Any solib trampoline code can be handled in reverse
6712 by simply continuing to single-step. We have already
6713 executed the solib function (backwards), and a few
6714 steps will take us back through the trampoline to the
6720 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
6722 /* We're doing a "next".
6724 Normal (forward) execution: set a breakpoint at the
6725 callee's return address (the address at which the caller
6728 Reverse (backward) execution. set the step-resume
6729 breakpoint at the start of the function that we just
6730 stepped into (backwards), and continue to there. When we
6731 get there, we'll need to single-step back to the caller. */
6733 if (execution_direction == EXEC_REVERSE)
6735 /* If we're already at the start of the function, we've either
6736 just stepped backward into a single instruction function,
6737 or stepped back out of a signal handler to the first instruction
6738 of the function. Just keep going, which will single-step back
6740 if (ecs->stop_func_start != stop_pc && ecs->stop_func_start != 0)
6742 struct symtab_and_line sr_sal;
6744 /* Normal function call return (static or dynamic). */
6746 sr_sal.pc = ecs->stop_func_start;
6747 sr_sal.pspace = get_frame_program_space (frame);
6748 insert_step_resume_breakpoint_at_sal (gdbarch,
6749 sr_sal, null_frame_id);
6753 insert_step_resume_breakpoint_at_caller (frame);
6759 /* If we are in a function call trampoline (a stub between the
6760 calling routine and the real function), locate the real
6761 function. That's what tells us (a) whether we want to step
6762 into it at all, and (b) what prologue we want to run to the
6763 end of, if we do step into it. */
6764 real_stop_pc = skip_language_trampoline (frame, stop_pc);
6765 if (real_stop_pc == 0)
6766 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
6767 if (real_stop_pc != 0)
6768 ecs->stop_func_start = real_stop_pc;
6770 if (real_stop_pc != 0 && in_solib_dynsym_resolve_code (real_stop_pc))
6772 struct symtab_and_line sr_sal;
6775 sr_sal.pc = ecs->stop_func_start;
6776 sr_sal.pspace = get_frame_program_space (frame);
6778 insert_step_resume_breakpoint_at_sal (gdbarch,
6779 sr_sal, null_frame_id);
6784 /* If we have line number information for the function we are
6785 thinking of stepping into and the function isn't on the skip
6788 If there are several symtabs at that PC (e.g. with include
6789 files), just want to know whether *any* of them have line
6790 numbers. find_pc_line handles this. */
6792 struct symtab_and_line tmp_sal;
6794 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
6795 if (tmp_sal.line != 0
6796 && !function_name_is_marked_for_skip (ecs->stop_func_name,
6799 if (execution_direction == EXEC_REVERSE)
6800 handle_step_into_function_backward (gdbarch, ecs);
6802 handle_step_into_function (gdbarch, ecs);
6807 /* If we have no line number and the step-stop-if-no-debug is
6808 set, we stop the step so that the user has a chance to switch
6809 in assembly mode. */
6810 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6811 && step_stop_if_no_debug)
6813 end_stepping_range (ecs);
6817 if (execution_direction == EXEC_REVERSE)
6819 /* If we're already at the start of the function, we've either just
6820 stepped backward into a single instruction function without line
6821 number info, or stepped back out of a signal handler to the first
6822 instruction of the function without line number info. Just keep
6823 going, which will single-step back to the caller. */
6824 if (ecs->stop_func_start != stop_pc)
6826 /* Set a breakpoint at callee's start address.
6827 From there we can step once and be back in the caller. */
6828 struct symtab_and_line sr_sal;
6831 sr_sal.pc = ecs->stop_func_start;
6832 sr_sal.pspace = get_frame_program_space (frame);
6833 insert_step_resume_breakpoint_at_sal (gdbarch,
6834 sr_sal, null_frame_id);
6838 /* Set a breakpoint at callee's return address (the address
6839 at which the caller will resume). */
6840 insert_step_resume_breakpoint_at_caller (frame);
6846 /* Reverse stepping through solib trampolines. */
6848 if (execution_direction == EXEC_REVERSE
6849 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
6851 if (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
6852 || (ecs->stop_func_start == 0
6853 && in_solib_dynsym_resolve_code (stop_pc)))
6855 /* Any solib trampoline code can be handled in reverse
6856 by simply continuing to single-step. We have already
6857 executed the solib function (backwards), and a few
6858 steps will take us back through the trampoline to the
6863 else if (in_solib_dynsym_resolve_code (stop_pc))
6865 /* Stepped backward into the solib dynsym resolver.
6866 Set a breakpoint at its start and continue, then
6867 one more step will take us out. */
6868 struct symtab_and_line sr_sal;
6871 sr_sal.pc = ecs->stop_func_start;
6872 sr_sal.pspace = get_frame_program_space (frame);
6873 insert_step_resume_breakpoint_at_sal (gdbarch,
6874 sr_sal, null_frame_id);
6880 stop_pc_sal = find_pc_line (stop_pc, 0);
6882 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6883 the trampoline processing logic, however, there are some trampolines
6884 that have no names, so we should do trampoline handling first. */
6885 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6886 && ecs->stop_func_name == NULL
6887 && stop_pc_sal.line == 0)
6890 fprintf_unfiltered (gdb_stdlog,
6891 "infrun: stepped into undebuggable function\n");
6893 /* The inferior just stepped into, or returned to, an
6894 undebuggable function (where there is no debugging information
6895 and no line number corresponding to the address where the
6896 inferior stopped). Since we want to skip this kind of code,
6897 we keep going until the inferior returns from this
6898 function - unless the user has asked us not to (via
6899 set step-mode) or we no longer know how to get back
6900 to the call site. */
6901 if (step_stop_if_no_debug
6902 || !frame_id_p (frame_unwind_caller_id (frame)))
6904 /* If we have no line number and the step-stop-if-no-debug
6905 is set, we stop the step so that the user has a chance to
6906 switch in assembly mode. */
6907 end_stepping_range (ecs);
6912 /* Set a breakpoint at callee's return address (the address
6913 at which the caller will resume). */
6914 insert_step_resume_breakpoint_at_caller (frame);
6920 if (ecs->event_thread->control.step_range_end == 1)
6922 /* It is stepi or nexti. We always want to stop stepping after
6925 fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
6926 end_stepping_range (ecs);
6930 if (stop_pc_sal.line == 0)
6932 /* We have no line number information. That means to stop
6933 stepping (does this always happen right after one instruction,
6934 when we do "s" in a function with no line numbers,
6935 or can this happen as a result of a return or longjmp?). */
6937 fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n");
6938 end_stepping_range (ecs);
6942 /* Look for "calls" to inlined functions, part one. If the inline
6943 frame machinery detected some skipped call sites, we have entered
6944 a new inline function. */
6946 if (frame_id_eq (get_frame_id (get_current_frame ()),
6947 ecs->event_thread->control.step_frame_id)
6948 && inline_skipped_frames (ecs->ptid))
6950 struct symtab_and_line call_sal;
6953 fprintf_unfiltered (gdb_stdlog,
6954 "infrun: stepped into inlined function\n");
6956 find_frame_sal (get_current_frame (), &call_sal);
6958 if (ecs->event_thread->control.step_over_calls != STEP_OVER_ALL)
6960 /* For "step", we're going to stop. But if the call site
6961 for this inlined function is on the same source line as
6962 we were previously stepping, go down into the function
6963 first. Otherwise stop at the call site. */
6965 if (call_sal.line == ecs->event_thread->current_line
6966 && call_sal.symtab == ecs->event_thread->current_symtab)
6967 step_into_inline_frame (ecs->ptid);
6969 end_stepping_range (ecs);
6974 /* For "next", we should stop at the call site if it is on a
6975 different source line. Otherwise continue through the
6976 inlined function. */
6977 if (call_sal.line == ecs->event_thread->current_line
6978 && call_sal.symtab == ecs->event_thread->current_symtab)
6981 end_stepping_range (ecs);
6986 /* Look for "calls" to inlined functions, part two. If we are still
6987 in the same real function we were stepping through, but we have
6988 to go further up to find the exact frame ID, we are stepping
6989 through a more inlined call beyond its call site. */
6991 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6992 && !frame_id_eq (get_frame_id (get_current_frame ()),
6993 ecs->event_thread->control.step_frame_id)
6994 && stepped_in_from (get_current_frame (),
6995 ecs->event_thread->control.step_frame_id))
6998 fprintf_unfiltered (gdb_stdlog,
6999 "infrun: stepping through inlined function\n");
7001 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
7004 end_stepping_range (ecs);
7008 if ((stop_pc == stop_pc_sal.pc)
7009 && (ecs->event_thread->current_line != stop_pc_sal.line
7010 || ecs->event_thread->current_symtab != stop_pc_sal.symtab))
7012 /* We are at the start of a different line. So stop. Note that
7013 we don't stop if we step into the middle of a different line.
7014 That is said to make things like for (;;) statements work
7017 fprintf_unfiltered (gdb_stdlog,
7018 "infrun: stepped to a different line\n");
7019 end_stepping_range (ecs);
7023 /* We aren't done stepping.
7025 Optimize by setting the stepping range to the line.
7026 (We might not be in the original line, but if we entered a
7027 new line in mid-statement, we continue stepping. This makes
7028 things like for(;;) statements work better.) */
7030 ecs->event_thread->control.step_range_start = stop_pc_sal.pc;
7031 ecs->event_thread->control.step_range_end = stop_pc_sal.end;
7032 ecs->event_thread->control.may_range_step = 1;
7033 set_step_info (frame, stop_pc_sal);
7036 fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n");
7040 /* In all-stop mode, if we're currently stepping but have stopped in
7041 some other thread, we may need to switch back to the stepped
7042 thread. Returns true we set the inferior running, false if we left
7043 it stopped (and the event needs further processing). */
7046 switch_back_to_stepped_thread (struct execution_control_state *ecs)
7048 if (!target_is_non_stop_p ())
7050 struct thread_info *tp;
7051 struct thread_info *stepping_thread;
7053 /* If any thread is blocked on some internal breakpoint, and we
7054 simply need to step over that breakpoint to get it going
7055 again, do that first. */
7057 /* However, if we see an event for the stepping thread, then we
7058 know all other threads have been moved past their breakpoints
7059 already. Let the caller check whether the step is finished,
7060 etc., before deciding to move it past a breakpoint. */
7061 if (ecs->event_thread->control.step_range_end != 0)
7064 /* Check if the current thread is blocked on an incomplete
7065 step-over, interrupted by a random signal. */
7066 if (ecs->event_thread->control.trap_expected
7067 && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_TRAP)
7071 fprintf_unfiltered (gdb_stdlog,
7072 "infrun: need to finish step-over of [%s]\n",
7073 target_pid_to_str (ecs->event_thread->ptid));
7079 /* Check if the current thread is blocked by a single-step
7080 breakpoint of another thread. */
7081 if (ecs->hit_singlestep_breakpoint)
7085 fprintf_unfiltered (gdb_stdlog,
7086 "infrun: need to step [%s] over single-step "
7088 target_pid_to_str (ecs->ptid));
7094 /* If this thread needs yet another step-over (e.g., stepping
7095 through a delay slot), do it first before moving on to
7097 if (thread_still_needs_step_over (ecs->event_thread))
7101 fprintf_unfiltered (gdb_stdlog,
7102 "infrun: thread [%s] still needs step-over\n",
7103 target_pid_to_str (ecs->event_thread->ptid));
7109 /* If scheduler locking applies even if not stepping, there's no
7110 need to walk over threads. Above we've checked whether the
7111 current thread is stepping. If some other thread not the
7112 event thread is stepping, then it must be that scheduler
7113 locking is not in effect. */
7114 if (schedlock_applies (ecs->event_thread))
7117 /* Otherwise, we no longer expect a trap in the current thread.
7118 Clear the trap_expected flag before switching back -- this is
7119 what keep_going does as well, if we call it. */
7120 ecs->event_thread->control.trap_expected = 0;
7122 /* Likewise, clear the signal if it should not be passed. */
7123 if (!signal_program[ecs->event_thread->suspend.stop_signal])
7124 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
7126 /* Do all pending step-overs before actually proceeding with
7128 if (start_step_over ())
7130 prepare_to_wait (ecs);
7134 /* Look for the stepping/nexting thread. */
7135 stepping_thread = NULL;
7137 ALL_NON_EXITED_THREADS (tp)
7139 /* Ignore threads of processes the caller is not
7142 && ptid_get_pid (tp->ptid) != ptid_get_pid (ecs->ptid))
7145 /* When stepping over a breakpoint, we lock all threads
7146 except the one that needs to move past the breakpoint.
7147 If a non-event thread has this set, the "incomplete
7148 step-over" check above should have caught it earlier. */
7149 if (tp->control.trap_expected)
7151 internal_error (__FILE__, __LINE__,
7152 "[%s] has inconsistent state: "
7153 "trap_expected=%d\n",
7154 target_pid_to_str (tp->ptid),
7155 tp->control.trap_expected);
7158 /* Did we find the stepping thread? */
7159 if (tp->control.step_range_end)
7161 /* Yep. There should only one though. */
7162 gdb_assert (stepping_thread == NULL);
7164 /* The event thread is handled at the top, before we
7166 gdb_assert (tp != ecs->event_thread);
7168 /* If some thread other than the event thread is
7169 stepping, then scheduler locking can't be in effect,
7170 otherwise we wouldn't have resumed the current event
7171 thread in the first place. */
7172 gdb_assert (!schedlock_applies (tp));
7174 stepping_thread = tp;
7178 if (stepping_thread != NULL)
7181 fprintf_unfiltered (gdb_stdlog,
7182 "infrun: switching back to stepped thread\n");
7184 if (keep_going_stepped_thread (stepping_thread))
7186 prepare_to_wait (ecs);
7195 /* Set a previously stepped thread back to stepping. Returns true on
7196 success, false if the resume is not possible (e.g., the thread
7200 keep_going_stepped_thread (struct thread_info *tp)
7202 struct frame_info *frame;
7203 struct execution_control_state ecss;
7204 struct execution_control_state *ecs = &ecss;
7206 /* If the stepping thread exited, then don't try to switch back and
7207 resume it, which could fail in several different ways depending
7208 on the target. Instead, just keep going.
7210 We can find a stepping dead thread in the thread list in two
7213 - The target supports thread exit events, and when the target
7214 tries to delete the thread from the thread list, inferior_ptid
7215 pointed at the exiting thread. In such case, calling
7216 delete_thread does not really remove the thread from the list;
7217 instead, the thread is left listed, with 'exited' state.
7219 - The target's debug interface does not support thread exit
7220 events, and so we have no idea whatsoever if the previously
7221 stepping thread is still alive. For that reason, we need to
7222 synchronously query the target now. */
7224 if (is_exited (tp->ptid)
7225 || !target_thread_alive (tp->ptid))
7228 fprintf_unfiltered (gdb_stdlog,
7229 "infrun: not resuming previously "
7230 "stepped thread, it has vanished\n");
7232 delete_thread (tp->ptid);
7237 fprintf_unfiltered (gdb_stdlog,
7238 "infrun: resuming previously stepped thread\n");
7240 reset_ecs (ecs, tp);
7241 switch_to_thread (tp->ptid);
7243 stop_pc = regcache_read_pc (get_thread_regcache (tp->ptid));
7244 frame = get_current_frame ();
7246 /* If the PC of the thread we were trying to single-step has
7247 changed, then that thread has trapped or been signaled, but the
7248 event has not been reported to GDB yet. Re-poll the target
7249 looking for this particular thread's event (i.e. temporarily
7250 enable schedlock) by:
7252 - setting a break at the current PC
7253 - resuming that particular thread, only (by setting trap
7256 This prevents us continuously moving the single-step breakpoint
7257 forward, one instruction at a time, overstepping. */
7259 if (stop_pc != tp->prev_pc)
7264 fprintf_unfiltered (gdb_stdlog,
7265 "infrun: expected thread advanced also (%s -> %s)\n",
7266 paddress (target_gdbarch (), tp->prev_pc),
7267 paddress (target_gdbarch (), stop_pc));
7269 /* Clear the info of the previous step-over, as it's no longer
7270 valid (if the thread was trying to step over a breakpoint, it
7271 has already succeeded). It's what keep_going would do too,
7272 if we called it. Do this before trying to insert the sss
7273 breakpoint, otherwise if we were previously trying to step
7274 over this exact address in another thread, the breakpoint is
7276 clear_step_over_info ();
7277 tp->control.trap_expected = 0;
7279 insert_single_step_breakpoint (get_frame_arch (frame),
7280 get_frame_address_space (frame),
7284 resume_ptid = internal_resume_ptid (tp->control.stepping_command);
7285 do_target_resume (resume_ptid, 0, GDB_SIGNAL_0);
7290 fprintf_unfiltered (gdb_stdlog,
7291 "infrun: expected thread still hasn't advanced\n");
7293 keep_going_pass_signal (ecs);
7298 /* Is thread TP in the middle of (software or hardware)
7299 single-stepping? (Note the result of this function must never be
7300 passed directly as target_resume's STEP parameter.) */
7303 currently_stepping (struct thread_info *tp)
7305 return ((tp->control.step_range_end
7306 && tp->control.step_resume_breakpoint == NULL)
7307 || tp->control.trap_expected
7308 || tp->stepped_breakpoint
7309 || bpstat_should_step ());
7312 /* Inferior has stepped into a subroutine call with source code that
7313 we should not step over. Do step to the first line of code in
7317 handle_step_into_function (struct gdbarch *gdbarch,
7318 struct execution_control_state *ecs)
7320 struct compunit_symtab *cust;
7321 struct symtab_and_line stop_func_sal, sr_sal;
7323 fill_in_stop_func (gdbarch, ecs);
7325 cust = find_pc_compunit_symtab (stop_pc);
7326 if (cust != NULL && compunit_language (cust) != language_asm)
7327 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
7328 ecs->stop_func_start);
7330 stop_func_sal = find_pc_line (ecs->stop_func_start, 0);
7331 /* Use the step_resume_break to step until the end of the prologue,
7332 even if that involves jumps (as it seems to on the vax under
7334 /* If the prologue ends in the middle of a source line, continue to
7335 the end of that source line (if it is still within the function).
7336 Otherwise, just go to end of prologue. */
7337 if (stop_func_sal.end
7338 && stop_func_sal.pc != ecs->stop_func_start
7339 && stop_func_sal.end < ecs->stop_func_end)
7340 ecs->stop_func_start = stop_func_sal.end;
7342 /* Architectures which require breakpoint adjustment might not be able
7343 to place a breakpoint at the computed address. If so, the test
7344 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7345 ecs->stop_func_start to an address at which a breakpoint may be
7346 legitimately placed.
7348 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7349 made, GDB will enter an infinite loop when stepping through
7350 optimized code consisting of VLIW instructions which contain
7351 subinstructions corresponding to different source lines. On
7352 FR-V, it's not permitted to place a breakpoint on any but the
7353 first subinstruction of a VLIW instruction. When a breakpoint is
7354 set, GDB will adjust the breakpoint address to the beginning of
7355 the VLIW instruction. Thus, we need to make the corresponding
7356 adjustment here when computing the stop address. */
7358 if (gdbarch_adjust_breakpoint_address_p (gdbarch))
7360 ecs->stop_func_start
7361 = gdbarch_adjust_breakpoint_address (gdbarch,
7362 ecs->stop_func_start);
7365 if (ecs->stop_func_start == stop_pc)
7367 /* We are already there: stop now. */
7368 end_stepping_range (ecs);
7373 /* Put the step-breakpoint there and go until there. */
7374 init_sal (&sr_sal); /* initialize to zeroes */
7375 sr_sal.pc = ecs->stop_func_start;
7376 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
7377 sr_sal.pspace = get_frame_program_space (get_current_frame ());
7379 /* Do not specify what the fp should be when we stop since on
7380 some machines the prologue is where the new fp value is
7382 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal, null_frame_id);
7384 /* And make sure stepping stops right away then. */
7385 ecs->event_thread->control.step_range_end
7386 = ecs->event_thread->control.step_range_start;
7391 /* Inferior has stepped backward into a subroutine call with source
7392 code that we should not step over. Do step to the beginning of the
7393 last line of code in it. */
7396 handle_step_into_function_backward (struct gdbarch *gdbarch,
7397 struct execution_control_state *ecs)
7399 struct compunit_symtab *cust;
7400 struct symtab_and_line stop_func_sal;
7402 fill_in_stop_func (gdbarch, ecs);
7404 cust = find_pc_compunit_symtab (stop_pc);
7405 if (cust != NULL && compunit_language (cust) != language_asm)
7406 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
7407 ecs->stop_func_start);
7409 stop_func_sal = find_pc_line (stop_pc, 0);
7411 /* OK, we're just going to keep stepping here. */
7412 if (stop_func_sal.pc == stop_pc)
7414 /* We're there already. Just stop stepping now. */
7415 end_stepping_range (ecs);
7419 /* Else just reset the step range and keep going.
7420 No step-resume breakpoint, they don't work for
7421 epilogues, which can have multiple entry paths. */
7422 ecs->event_thread->control.step_range_start = stop_func_sal.pc;
7423 ecs->event_thread->control.step_range_end = stop_func_sal.end;
7429 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7430 This is used to both functions and to skip over code. */
7433 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch *gdbarch,
7434 struct symtab_and_line sr_sal,
7435 struct frame_id sr_id,
7436 enum bptype sr_type)
7438 /* There should never be more than one step-resume or longjmp-resume
7439 breakpoint per thread, so we should never be setting a new
7440 step_resume_breakpoint when one is already active. */
7441 gdb_assert (inferior_thread ()->control.step_resume_breakpoint == NULL);
7442 gdb_assert (sr_type == bp_step_resume || sr_type == bp_hp_step_resume);
7445 fprintf_unfiltered (gdb_stdlog,
7446 "infrun: inserting step-resume breakpoint at %s\n",
7447 paddress (gdbarch, sr_sal.pc));
7449 inferior_thread ()->control.step_resume_breakpoint
7450 = set_momentary_breakpoint (gdbarch, sr_sal, sr_id, sr_type);
7454 insert_step_resume_breakpoint_at_sal (struct gdbarch *gdbarch,
7455 struct symtab_and_line sr_sal,
7456 struct frame_id sr_id)
7458 insert_step_resume_breakpoint_at_sal_1 (gdbarch,
7463 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7464 This is used to skip a potential signal handler.
7466 This is called with the interrupted function's frame. The signal
7467 handler, when it returns, will resume the interrupted function at
7471 insert_hp_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
7473 struct symtab_and_line sr_sal;
7474 struct gdbarch *gdbarch;
7476 gdb_assert (return_frame != NULL);
7477 init_sal (&sr_sal); /* initialize to zeros */
7479 gdbarch = get_frame_arch (return_frame);
7480 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch, get_frame_pc (return_frame));
7481 sr_sal.section = find_pc_overlay (sr_sal.pc);
7482 sr_sal.pspace = get_frame_program_space (return_frame);
7484 insert_step_resume_breakpoint_at_sal_1 (gdbarch, sr_sal,
7485 get_stack_frame_id (return_frame),
7489 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7490 is used to skip a function after stepping into it (for "next" or if
7491 the called function has no debugging information).
7493 The current function has almost always been reached by single
7494 stepping a call or return instruction. NEXT_FRAME belongs to the
7495 current function, and the breakpoint will be set at the caller's
7498 This is a separate function rather than reusing
7499 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7500 get_prev_frame, which may stop prematurely (see the implementation
7501 of frame_unwind_caller_id for an example). */
7504 insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame)
7506 struct symtab_and_line sr_sal;
7507 struct gdbarch *gdbarch;
7509 /* We shouldn't have gotten here if we don't know where the call site
7511 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame)));
7513 init_sal (&sr_sal); /* initialize to zeros */
7515 gdbarch = frame_unwind_caller_arch (next_frame);
7516 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch,
7517 frame_unwind_caller_pc (next_frame));
7518 sr_sal.section = find_pc_overlay (sr_sal.pc);
7519 sr_sal.pspace = frame_unwind_program_space (next_frame);
7521 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal,
7522 frame_unwind_caller_id (next_frame));
7525 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7526 new breakpoint at the target of a jmp_buf. The handling of
7527 longjmp-resume uses the same mechanisms used for handling
7528 "step-resume" breakpoints. */
7531 insert_longjmp_resume_breakpoint (struct gdbarch *gdbarch, CORE_ADDR pc)
7533 /* There should never be more than one longjmp-resume breakpoint per
7534 thread, so we should never be setting a new
7535 longjmp_resume_breakpoint when one is already active. */
7536 gdb_assert (inferior_thread ()->control.exception_resume_breakpoint == NULL);
7539 fprintf_unfiltered (gdb_stdlog,
7540 "infrun: inserting longjmp-resume breakpoint at %s\n",
7541 paddress (gdbarch, pc));
7543 inferior_thread ()->control.exception_resume_breakpoint =
7544 set_momentary_breakpoint_at_pc (gdbarch, pc, bp_longjmp_resume);
7547 /* Insert an exception resume breakpoint. TP is the thread throwing
7548 the exception. The block B is the block of the unwinder debug hook
7549 function. FRAME is the frame corresponding to the call to this
7550 function. SYM is the symbol of the function argument holding the
7551 target PC of the exception. */
7554 insert_exception_resume_breakpoint (struct thread_info *tp,
7555 const struct block *b,
7556 struct frame_info *frame,
7561 struct block_symbol vsym;
7562 struct value *value;
7564 struct breakpoint *bp;
7566 vsym = lookup_symbol (SYMBOL_LINKAGE_NAME (sym), b, VAR_DOMAIN, NULL);
7567 value = read_var_value (vsym.symbol, vsym.block, frame);
7568 /* If the value was optimized out, revert to the old behavior. */
7569 if (! value_optimized_out (value))
7571 handler = value_as_address (value);
7574 fprintf_unfiltered (gdb_stdlog,
7575 "infrun: exception resume at %lx\n",
7576 (unsigned long) handler);
7578 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
7579 handler, bp_exception_resume);
7581 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7584 bp->thread = tp->global_num;
7585 inferior_thread ()->control.exception_resume_breakpoint = bp;
7588 CATCH (e, RETURN_MASK_ERROR)
7590 /* We want to ignore errors here. */
7595 /* A helper for check_exception_resume that sets an
7596 exception-breakpoint based on a SystemTap probe. */
7599 insert_exception_resume_from_probe (struct thread_info *tp,
7600 const struct bound_probe *probe,
7601 struct frame_info *frame)
7603 struct value *arg_value;
7605 struct breakpoint *bp;
7607 arg_value = probe_safe_evaluate_at_pc (frame, 1);
7611 handler = value_as_address (arg_value);
7614 fprintf_unfiltered (gdb_stdlog,
7615 "infrun: exception resume at %s\n",
7616 paddress (get_objfile_arch (probe->objfile),
7619 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
7620 handler, bp_exception_resume);
7621 bp->thread = tp->global_num;
7622 inferior_thread ()->control.exception_resume_breakpoint = bp;
7625 /* This is called when an exception has been intercepted. Check to
7626 see whether the exception's destination is of interest, and if so,
7627 set an exception resume breakpoint there. */
7630 check_exception_resume (struct execution_control_state *ecs,
7631 struct frame_info *frame)
7633 struct bound_probe probe;
7634 struct symbol *func;
7636 /* First see if this exception unwinding breakpoint was set via a
7637 SystemTap probe point. If so, the probe has two arguments: the
7638 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7639 set a breakpoint there. */
7640 probe = find_probe_by_pc (get_frame_pc (frame));
7643 insert_exception_resume_from_probe (ecs->event_thread, &probe, frame);
7647 func = get_frame_function (frame);
7653 const struct block *b;
7654 struct block_iterator iter;
7658 /* The exception breakpoint is a thread-specific breakpoint on
7659 the unwinder's debug hook, declared as:
7661 void _Unwind_DebugHook (void *cfa, void *handler);
7663 The CFA argument indicates the frame to which control is
7664 about to be transferred. HANDLER is the destination PC.
7666 We ignore the CFA and set a temporary breakpoint at HANDLER.
7667 This is not extremely efficient but it avoids issues in gdb
7668 with computing the DWARF CFA, and it also works even in weird
7669 cases such as throwing an exception from inside a signal
7672 b = SYMBOL_BLOCK_VALUE (func);
7673 ALL_BLOCK_SYMBOLS (b, iter, sym)
7675 if (!SYMBOL_IS_ARGUMENT (sym))
7682 insert_exception_resume_breakpoint (ecs->event_thread,
7688 CATCH (e, RETURN_MASK_ERROR)
7695 stop_waiting (struct execution_control_state *ecs)
7698 fprintf_unfiltered (gdb_stdlog, "infrun: stop_waiting\n");
7700 clear_step_over_info ();
7702 /* Let callers know we don't want to wait for the inferior anymore. */
7703 ecs->wait_some_more = 0;
7705 /* If all-stop, but the target is always in non-stop mode, stop all
7706 threads now that we're presenting the stop to the user. */
7707 if (!non_stop && target_is_non_stop_p ())
7708 stop_all_threads ();
7711 /* Like keep_going, but passes the signal to the inferior, even if the
7712 signal is set to nopass. */
7715 keep_going_pass_signal (struct execution_control_state *ecs)
7717 /* Make sure normal_stop is called if we get a QUIT handled before
7719 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
7721 gdb_assert (ptid_equal (ecs->event_thread->ptid, inferior_ptid));
7722 gdb_assert (!ecs->event_thread->resumed);
7724 /* Save the pc before execution, to compare with pc after stop. */
7725 ecs->event_thread->prev_pc
7726 = regcache_read_pc (get_thread_regcache (ecs->ptid));
7728 if (ecs->event_thread->control.trap_expected)
7730 struct thread_info *tp = ecs->event_thread;
7733 fprintf_unfiltered (gdb_stdlog,
7734 "infrun: %s has trap_expected set, "
7735 "resuming to collect trap\n",
7736 target_pid_to_str (tp->ptid));
7738 /* We haven't yet gotten our trap, and either: intercepted a
7739 non-signal event (e.g., a fork); or took a signal which we
7740 are supposed to pass through to the inferior. Simply
7742 discard_cleanups (old_cleanups);
7743 resume (ecs->event_thread->suspend.stop_signal);
7745 else if (step_over_info_valid_p ())
7747 /* Another thread is stepping over a breakpoint in-line. If
7748 this thread needs a step-over too, queue the request. In
7749 either case, this resume must be deferred for later. */
7750 struct thread_info *tp = ecs->event_thread;
7752 if (ecs->hit_singlestep_breakpoint
7753 || thread_still_needs_step_over (tp))
7756 fprintf_unfiltered (gdb_stdlog,
7757 "infrun: step-over already in progress: "
7758 "step-over for %s deferred\n",
7759 target_pid_to_str (tp->ptid));
7760 thread_step_over_chain_enqueue (tp);
7765 fprintf_unfiltered (gdb_stdlog,
7766 "infrun: step-over in progress: "
7767 "resume of %s deferred\n",
7768 target_pid_to_str (tp->ptid));
7771 discard_cleanups (old_cleanups);
7775 struct regcache *regcache = get_current_regcache ();
7778 step_over_what step_what;
7780 /* Either the trap was not expected, but we are continuing
7781 anyway (if we got a signal, the user asked it be passed to
7784 We got our expected trap, but decided we should resume from
7787 We're going to run this baby now!
7789 Note that insert_breakpoints won't try to re-insert
7790 already inserted breakpoints. Therefore, we don't
7791 care if breakpoints were already inserted, or not. */
7793 /* If we need to step over a breakpoint, and we're not using
7794 displaced stepping to do so, insert all breakpoints
7795 (watchpoints, etc.) but the one we're stepping over, step one
7796 instruction, and then re-insert the breakpoint when that step
7799 step_what = thread_still_needs_step_over (ecs->event_thread);
7801 remove_bp = (ecs->hit_singlestep_breakpoint
7802 || (step_what & STEP_OVER_BREAKPOINT));
7803 remove_wps = (step_what & STEP_OVER_WATCHPOINT);
7805 /* We can't use displaced stepping if we need to step past a
7806 watchpoint. The instruction copied to the scratch pad would
7807 still trigger the watchpoint. */
7809 && (remove_wps || !use_displaced_stepping (ecs->event_thread)))
7811 set_step_over_info (get_regcache_aspace (regcache),
7812 regcache_read_pc (regcache), remove_wps,
7813 ecs->event_thread->global_num);
7815 else if (remove_wps)
7816 set_step_over_info (NULL, 0, remove_wps, -1);
7818 /* If we now need to do an in-line step-over, we need to stop
7819 all other threads. Note this must be done before
7820 insert_breakpoints below, because that removes the breakpoint
7821 we're about to step over, otherwise other threads could miss
7823 if (step_over_info_valid_p () && target_is_non_stop_p ())
7824 stop_all_threads ();
7826 /* Stop stepping if inserting breakpoints fails. */
7829 insert_breakpoints ();
7831 CATCH (e, RETURN_MASK_ERROR)
7833 exception_print (gdb_stderr, e);
7835 discard_cleanups (old_cleanups);
7840 ecs->event_thread->control.trap_expected = (remove_bp || remove_wps);
7842 discard_cleanups (old_cleanups);
7843 resume (ecs->event_thread->suspend.stop_signal);
7846 prepare_to_wait (ecs);
7849 /* Called when we should continue running the inferior, because the
7850 current event doesn't cause a user visible stop. This does the
7851 resuming part; waiting for the next event is done elsewhere. */
7854 keep_going (struct execution_control_state *ecs)
7856 if (ecs->event_thread->control.trap_expected
7857 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
7858 ecs->event_thread->control.trap_expected = 0;
7860 if (!signal_program[ecs->event_thread->suspend.stop_signal])
7861 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
7862 keep_going_pass_signal (ecs);
7865 /* This function normally comes after a resume, before
7866 handle_inferior_event exits. It takes care of any last bits of
7867 housekeeping, and sets the all-important wait_some_more flag. */
7870 prepare_to_wait (struct execution_control_state *ecs)
7873 fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n");
7875 ecs->wait_some_more = 1;
7877 if (!target_is_async_p ())
7878 mark_infrun_async_event_handler ();
7881 /* We are done with the step range of a step/next/si/ni command.
7882 Called once for each n of a "step n" operation. */
7885 end_stepping_range (struct execution_control_state *ecs)
7887 ecs->event_thread->control.stop_step = 1;
7891 /* Several print_*_reason functions to print why the inferior has stopped.
7892 We always print something when the inferior exits, or receives a signal.
7893 The rest of the cases are dealt with later on in normal_stop and
7894 print_it_typical. Ideally there should be a call to one of these
7895 print_*_reason functions functions from handle_inferior_event each time
7896 stop_waiting is called.
7898 Note that we don't call these directly, instead we delegate that to
7899 the interpreters, through observers. Interpreters then call these
7900 with whatever uiout is right. */
7903 print_end_stepping_range_reason (struct ui_out *uiout)
7905 /* For CLI-like interpreters, print nothing. */
7907 if (ui_out_is_mi_like_p (uiout))
7909 ui_out_field_string (uiout, "reason",
7910 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE));
7915 print_signal_exited_reason (struct ui_out *uiout, enum gdb_signal siggnal)
7917 annotate_signalled ();
7918 if (ui_out_is_mi_like_p (uiout))
7920 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED));
7921 ui_out_text (uiout, "\nProgram terminated with signal ");
7922 annotate_signal_name ();
7923 ui_out_field_string (uiout, "signal-name",
7924 gdb_signal_to_name (siggnal));
7925 annotate_signal_name_end ();
7926 ui_out_text (uiout, ", ");
7927 annotate_signal_string ();
7928 ui_out_field_string (uiout, "signal-meaning",
7929 gdb_signal_to_string (siggnal));
7930 annotate_signal_string_end ();
7931 ui_out_text (uiout, ".\n");
7932 ui_out_text (uiout, "The program no longer exists.\n");
7936 print_exited_reason (struct ui_out *uiout, int exitstatus)
7938 struct inferior *inf = current_inferior ();
7939 const char *pidstr = target_pid_to_str (pid_to_ptid (inf->pid));
7941 annotate_exited (exitstatus);
7944 if (ui_out_is_mi_like_p (uiout))
7945 ui_out_field_string (uiout, "reason",
7946 async_reason_lookup (EXEC_ASYNC_EXITED));
7947 ui_out_text (uiout, "[Inferior ");
7948 ui_out_text (uiout, plongest (inf->num));
7949 ui_out_text (uiout, " (");
7950 ui_out_text (uiout, pidstr);
7951 ui_out_text (uiout, ") exited with code ");
7952 ui_out_field_fmt (uiout, "exit-code", "0%o", (unsigned int) exitstatus);
7953 ui_out_text (uiout, "]\n");
7957 if (ui_out_is_mi_like_p (uiout))
7959 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY));
7960 ui_out_text (uiout, "[Inferior ");
7961 ui_out_text (uiout, plongest (inf->num));
7962 ui_out_text (uiout, " (");
7963 ui_out_text (uiout, pidstr);
7964 ui_out_text (uiout, ") exited normally]\n");
7968 /* Some targets/architectures can do extra processing/display of
7969 segmentation faults. E.g., Intel MPX boundary faults.
7970 Call the architecture dependent function to handle the fault. */
7973 handle_segmentation_fault (struct ui_out *uiout)
7975 struct regcache *regcache = get_current_regcache ();
7976 struct gdbarch *gdbarch = get_regcache_arch (regcache);
7978 if (gdbarch_handle_segmentation_fault_p (gdbarch))
7979 gdbarch_handle_segmentation_fault (gdbarch, uiout);
7983 print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal)
7985 struct thread_info *thr = inferior_thread ();
7989 if (ui_out_is_mi_like_p (uiout))
7991 else if (show_thread_that_caused_stop ())
7995 ui_out_text (uiout, "\nThread ");
7996 ui_out_field_fmt (uiout, "thread-id", "%s", print_thread_id (thr));
7998 name = thr->name != NULL ? thr->name : target_thread_name (thr);
8001 ui_out_text (uiout, " \"");
8002 ui_out_field_fmt (uiout, "name", "%s", name);
8003 ui_out_text (uiout, "\"");
8007 ui_out_text (uiout, "\nProgram");
8009 if (siggnal == GDB_SIGNAL_0 && !ui_out_is_mi_like_p (uiout))
8010 ui_out_text (uiout, " stopped");
8013 ui_out_text (uiout, " received signal ");
8014 annotate_signal_name ();
8015 if (ui_out_is_mi_like_p (uiout))
8017 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
8018 ui_out_field_string (uiout, "signal-name",
8019 gdb_signal_to_name (siggnal));
8020 annotate_signal_name_end ();
8021 ui_out_text (uiout, ", ");
8022 annotate_signal_string ();
8023 ui_out_field_string (uiout, "signal-meaning",
8024 gdb_signal_to_string (siggnal));
8026 if (siggnal == GDB_SIGNAL_SEGV)
8027 handle_segmentation_fault (uiout);
8029 annotate_signal_string_end ();
8031 ui_out_text (uiout, ".\n");
8035 print_no_history_reason (struct ui_out *uiout)
8037 ui_out_text (uiout, "\nNo more reverse-execution history.\n");
8040 /* Print current location without a level number, if we have changed
8041 functions or hit a breakpoint. Print source line if we have one.
8042 bpstat_print contains the logic deciding in detail what to print,
8043 based on the event(s) that just occurred. */
8046 print_stop_location (struct target_waitstatus *ws)
8049 enum print_what source_flag;
8050 int do_frame_printing = 1;
8051 struct thread_info *tp = inferior_thread ();
8053 bpstat_ret = bpstat_print (tp->control.stop_bpstat, ws->kind);
8057 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8058 should) carry around the function and does (or should) use
8059 that when doing a frame comparison. */
8060 if (tp->control.stop_step
8061 && frame_id_eq (tp->control.step_frame_id,
8062 get_frame_id (get_current_frame ()))
8063 && tp->control.step_start_function == find_pc_function (stop_pc))
8065 /* Finished step, just print source line. */
8066 source_flag = SRC_LINE;
8070 /* Print location and source line. */
8071 source_flag = SRC_AND_LOC;
8074 case PRINT_SRC_AND_LOC:
8075 /* Print location and source line. */
8076 source_flag = SRC_AND_LOC;
8078 case PRINT_SRC_ONLY:
8079 source_flag = SRC_LINE;
8082 /* Something bogus. */
8083 source_flag = SRC_LINE;
8084 do_frame_printing = 0;
8087 internal_error (__FILE__, __LINE__, _("Unknown value."));
8090 /* The behavior of this routine with respect to the source
8092 SRC_LINE: Print only source line
8093 LOCATION: Print only location
8094 SRC_AND_LOC: Print location and source line. */
8095 if (do_frame_printing)
8096 print_stack_frame (get_selected_frame (NULL), 0, source_flag, 1);
8099 /* Cleanup that restores a previous current uiout. */
8102 restore_current_uiout_cleanup (void *arg)
8104 struct ui_out *saved_uiout = (struct ui_out *) arg;
8106 current_uiout = saved_uiout;
8112 print_stop_event (struct ui_out *uiout)
8114 struct cleanup *old_chain;
8115 struct target_waitstatus last;
8117 struct thread_info *tp;
8119 get_last_target_status (&last_ptid, &last);
8121 old_chain = make_cleanup (restore_current_uiout_cleanup, current_uiout);
8122 current_uiout = uiout;
8124 print_stop_location (&last);
8126 /* Display the auto-display expressions. */
8129 do_cleanups (old_chain);
8131 tp = inferior_thread ();
8132 if (tp->thread_fsm != NULL
8133 && thread_fsm_finished_p (tp->thread_fsm))
8135 struct return_value_info *rv;
8137 rv = thread_fsm_return_value (tp->thread_fsm);
8139 print_return_value (uiout, rv);
8146 maybe_remove_breakpoints (void)
8148 if (!breakpoints_should_be_inserted_now () && target_has_execution)
8150 if (remove_breakpoints ())
8152 target_terminal_ours_for_output ();
8153 printf_filtered (_("Cannot remove breakpoints because "
8154 "program is no longer writable.\nFurther "
8155 "execution is probably impossible.\n"));
8160 /* The execution context that just caused a normal stop. */
8167 /* The event PTID. */
8171 /* If stopp for a thread event, this is the thread that caused the
8173 struct thread_info *thread;
8175 /* The inferior that caused the stop. */
8179 /* Returns a new stop context. If stopped for a thread event, this
8180 takes a strong reference to the thread. */
8182 static struct stop_context *
8183 save_stop_context (void)
8185 struct stop_context *sc = XNEW (struct stop_context);
8187 sc->stop_id = get_stop_id ();
8188 sc->ptid = inferior_ptid;
8189 sc->inf_num = current_inferior ()->num;
8191 if (!ptid_equal (inferior_ptid, null_ptid))
8193 /* Take a strong reference so that the thread can't be deleted
8195 sc->thread = inferior_thread ();
8196 sc->thread->refcount++;
8204 /* Release a stop context previously created with save_stop_context.
8205 Releases the strong reference to the thread as well. */
8208 release_stop_context_cleanup (void *arg)
8210 struct stop_context *sc = (struct stop_context *) arg;
8212 if (sc->thread != NULL)
8213 sc->thread->refcount--;
8217 /* Return true if the current context no longer matches the saved stop
8221 stop_context_changed (struct stop_context *prev)
8223 if (!ptid_equal (prev->ptid, inferior_ptid))
8225 if (prev->inf_num != current_inferior ()->num)
8227 if (prev->thread != NULL && prev->thread->state != THREAD_STOPPED)
8229 if (get_stop_id () != prev->stop_id)
8239 struct target_waitstatus last;
8241 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
8243 struct switch_thru_all_uis state;
8245 get_last_target_status (&last_ptid, &last);
8249 /* If an exception is thrown from this point on, make sure to
8250 propagate GDB's knowledge of the executing state to the
8251 frontend/user running state. A QUIT is an easy exception to see
8252 here, so do this before any filtered output. */
8254 make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
8255 else if (last.kind == TARGET_WAITKIND_SIGNALLED
8256 || last.kind == TARGET_WAITKIND_EXITED)
8258 /* On some targets, we may still have live threads in the
8259 inferior when we get a process exit event. E.g., for
8260 "checkpoint", when the current checkpoint/fork exits,
8261 linux-fork.c automatically switches to another fork from
8262 within target_mourn_inferior. */
8263 if (!ptid_equal (inferior_ptid, null_ptid))
8265 pid_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
8266 make_cleanup (finish_thread_state_cleanup, &pid_ptid);
8269 else if (last.kind != TARGET_WAITKIND_NO_RESUMED)
8270 make_cleanup (finish_thread_state_cleanup, &inferior_ptid);
8272 /* As we're presenting a stop, and potentially removing breakpoints,
8273 update the thread list so we can tell whether there are threads
8274 running on the target. With target remote, for example, we can
8275 only learn about new threads when we explicitly update the thread
8276 list. Do this before notifying the interpreters about signal
8277 stops, end of stepping ranges, etc., so that the "new thread"
8278 output is emitted before e.g., "Program received signal FOO",
8279 instead of after. */
8280 update_thread_list ();
8282 if (last.kind == TARGET_WAITKIND_STOPPED && stopped_by_random_signal)
8283 observer_notify_signal_received (inferior_thread ()->suspend.stop_signal);
8285 /* As with the notification of thread events, we want to delay
8286 notifying the user that we've switched thread context until
8287 the inferior actually stops.
8289 There's no point in saying anything if the inferior has exited.
8290 Note that SIGNALLED here means "exited with a signal", not
8291 "received a signal".
8293 Also skip saying anything in non-stop mode. In that mode, as we
8294 don't want GDB to switch threads behind the user's back, to avoid
8295 races where the user is typing a command to apply to thread x,
8296 but GDB switches to thread y before the user finishes entering
8297 the command, fetch_inferior_event installs a cleanup to restore
8298 the current thread back to the thread the user had selected right
8299 after this event is handled, so we're not really switching, only
8300 informing of a stop. */
8302 && !ptid_equal (previous_inferior_ptid, inferior_ptid)
8303 && target_has_execution
8304 && last.kind != TARGET_WAITKIND_SIGNALLED
8305 && last.kind != TARGET_WAITKIND_EXITED
8306 && last.kind != TARGET_WAITKIND_NO_RESUMED)
8308 SWITCH_THRU_ALL_UIS (state)
8310 target_terminal_ours_for_output ();
8311 printf_filtered (_("[Switching to %s]\n"),
8312 target_pid_to_str (inferior_ptid));
8313 annotate_thread_changed ();
8315 previous_inferior_ptid = inferior_ptid;
8318 if (last.kind == TARGET_WAITKIND_NO_RESUMED)
8320 SWITCH_THRU_ALL_UIS (state)
8321 if (current_ui->prompt_state == PROMPT_BLOCKED)
8323 target_terminal_ours_for_output ();
8324 printf_filtered (_("No unwaited-for children left.\n"));
8328 /* Note: this depends on the update_thread_list call above. */
8329 maybe_remove_breakpoints ();
8331 /* If an auto-display called a function and that got a signal,
8332 delete that auto-display to avoid an infinite recursion. */
8334 if (stopped_by_random_signal)
8335 disable_current_display ();
8337 SWITCH_THRU_ALL_UIS (state)
8339 async_enable_stdin ();
8342 /* Let the user/frontend see the threads as stopped. */
8343 do_cleanups (old_chain);
8345 /* Select innermost stack frame - i.e., current frame is frame 0,
8346 and current location is based on that. Handle the case where the
8347 dummy call is returning after being stopped. E.g. the dummy call
8348 previously hit a breakpoint. (If the dummy call returns
8349 normally, we won't reach here.) Do this before the stop hook is
8350 run, so that it doesn't get to see the temporary dummy frame,
8351 which is not where we'll present the stop. */
8352 if (has_stack_frames ())
8354 if (stop_stack_dummy == STOP_STACK_DUMMY)
8356 /* Pop the empty frame that contains the stack dummy. This
8357 also restores inferior state prior to the call (struct
8358 infcall_suspend_state). */
8359 struct frame_info *frame = get_current_frame ();
8361 gdb_assert (get_frame_type (frame) == DUMMY_FRAME);
8363 /* frame_pop calls reinit_frame_cache as the last thing it
8364 does which means there's now no selected frame. */
8367 select_frame (get_current_frame ());
8369 /* Set the current source location. */
8370 set_current_sal_from_frame (get_current_frame ());
8373 /* Look up the hook_stop and run it (CLI internally handles problem
8374 of stop_command's pre-hook not existing). */
8375 if (stop_command != NULL)
8377 struct stop_context *saved_context = save_stop_context ();
8378 struct cleanup *old_chain
8379 = make_cleanup (release_stop_context_cleanup, saved_context);
8381 catch_errors (hook_stop_stub, stop_command,
8382 "Error while running hook_stop:\n", RETURN_MASK_ALL);
8384 /* If the stop hook resumes the target, then there's no point in
8385 trying to notify about the previous stop; its context is
8386 gone. Likewise if the command switches thread or inferior --
8387 the observers would print a stop for the wrong
8389 if (stop_context_changed (saved_context))
8391 do_cleanups (old_chain);
8394 do_cleanups (old_chain);
8397 /* Notify observers about the stop. This is where the interpreters
8398 print the stop event. */
8399 if (!ptid_equal (inferior_ptid, null_ptid))
8400 observer_notify_normal_stop (inferior_thread ()->control.stop_bpstat,
8403 observer_notify_normal_stop (NULL, stop_print_frame);
8405 annotate_stopped ();
8407 if (target_has_execution)
8409 if (last.kind != TARGET_WAITKIND_SIGNALLED
8410 && last.kind != TARGET_WAITKIND_EXITED)
8411 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8412 Delete any breakpoint that is to be deleted at the next stop. */
8413 breakpoint_auto_delete (inferior_thread ()->control.stop_bpstat);
8416 /* Try to get rid of automatically added inferiors that are no
8417 longer needed. Keeping those around slows down things linearly.
8418 Note that this never removes the current inferior. */
8425 hook_stop_stub (void *cmd)
8427 execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
8432 signal_stop_state (int signo)
8434 return signal_stop[signo];
8438 signal_print_state (int signo)
8440 return signal_print[signo];
8444 signal_pass_state (int signo)
8446 return signal_program[signo];
8450 signal_cache_update (int signo)
8454 for (signo = 0; signo < (int) GDB_SIGNAL_LAST; signo++)
8455 signal_cache_update (signo);
8460 signal_pass[signo] = (signal_stop[signo] == 0
8461 && signal_print[signo] == 0
8462 && signal_program[signo] == 1
8463 && signal_catch[signo] == 0);
8467 signal_stop_update (int signo, int state)
8469 int ret = signal_stop[signo];
8471 signal_stop[signo] = state;
8472 signal_cache_update (signo);
8477 signal_print_update (int signo, int state)
8479 int ret = signal_print[signo];
8481 signal_print[signo] = state;
8482 signal_cache_update (signo);
8487 signal_pass_update (int signo, int state)
8489 int ret = signal_program[signo];
8491 signal_program[signo] = state;
8492 signal_cache_update (signo);
8496 /* Update the global 'signal_catch' from INFO and notify the
8500 signal_catch_update (const unsigned int *info)
8504 for (i = 0; i < GDB_SIGNAL_LAST; ++i)
8505 signal_catch[i] = info[i] > 0;
8506 signal_cache_update (-1);
8507 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
8511 sig_print_header (void)
8513 printf_filtered (_("Signal Stop\tPrint\tPass "
8514 "to program\tDescription\n"));
8518 sig_print_info (enum gdb_signal oursig)
8520 const char *name = gdb_signal_to_name (oursig);
8521 int name_padding = 13 - strlen (name);
8523 if (name_padding <= 0)
8526 printf_filtered ("%s", name);
8527 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
8528 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
8529 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
8530 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
8531 printf_filtered ("%s\n", gdb_signal_to_string (oursig));
8534 /* Specify how various signals in the inferior should be handled. */
8537 handle_command (char *args, int from_tty)
8540 int digits, wordlen;
8541 int sigfirst, signum, siglast;
8542 enum gdb_signal oursig;
8545 unsigned char *sigs;
8546 struct cleanup *old_chain;
8550 error_no_arg (_("signal to handle"));
8553 /* Allocate and zero an array of flags for which signals to handle. */
8555 nsigs = (int) GDB_SIGNAL_LAST;
8556 sigs = (unsigned char *) alloca (nsigs);
8557 memset (sigs, 0, nsigs);
8559 /* Break the command line up into args. */
8561 argv = gdb_buildargv (args);
8562 old_chain = make_cleanup_freeargv (argv);
8564 /* Walk through the args, looking for signal oursigs, signal names, and
8565 actions. Signal numbers and signal names may be interspersed with
8566 actions, with the actions being performed for all signals cumulatively
8567 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8569 while (*argv != NULL)
8571 wordlen = strlen (*argv);
8572 for (digits = 0; isdigit ((*argv)[digits]); digits++)
8576 sigfirst = siglast = -1;
8578 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
8580 /* Apply action to all signals except those used by the
8581 debugger. Silently skip those. */
8584 siglast = nsigs - 1;
8586 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
8588 SET_SIGS (nsigs, sigs, signal_stop);
8589 SET_SIGS (nsigs, sigs, signal_print);
8591 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
8593 UNSET_SIGS (nsigs, sigs, signal_program);
8595 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
8597 SET_SIGS (nsigs, sigs, signal_print);
8599 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
8601 SET_SIGS (nsigs, sigs, signal_program);
8603 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
8605 UNSET_SIGS (nsigs, sigs, signal_stop);
8607 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
8609 SET_SIGS (nsigs, sigs, signal_program);
8611 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
8613 UNSET_SIGS (nsigs, sigs, signal_print);
8614 UNSET_SIGS (nsigs, sigs, signal_stop);
8616 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
8618 UNSET_SIGS (nsigs, sigs, signal_program);
8620 else if (digits > 0)
8622 /* It is numeric. The numeric signal refers to our own
8623 internal signal numbering from target.h, not to host/target
8624 signal number. This is a feature; users really should be
8625 using symbolic names anyway, and the common ones like
8626 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8628 sigfirst = siglast = (int)
8629 gdb_signal_from_command (atoi (*argv));
8630 if ((*argv)[digits] == '-')
8633 gdb_signal_from_command (atoi ((*argv) + digits + 1));
8635 if (sigfirst > siglast)
8637 /* Bet he didn't figure we'd think of this case... */
8645 oursig = gdb_signal_from_name (*argv);
8646 if (oursig != GDB_SIGNAL_UNKNOWN)
8648 sigfirst = siglast = (int) oursig;
8652 /* Not a number and not a recognized flag word => complain. */
8653 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv);
8657 /* If any signal numbers or symbol names were found, set flags for
8658 which signals to apply actions to. */
8660 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
8662 switch ((enum gdb_signal) signum)
8664 case GDB_SIGNAL_TRAP:
8665 case GDB_SIGNAL_INT:
8666 if (!allsigs && !sigs[signum])
8668 if (query (_("%s is used by the debugger.\n\
8669 Are you sure you want to change it? "),
8670 gdb_signal_to_name ((enum gdb_signal) signum)))
8676 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8677 gdb_flush (gdb_stdout);
8682 case GDB_SIGNAL_DEFAULT:
8683 case GDB_SIGNAL_UNKNOWN:
8684 /* Make sure that "all" doesn't print these. */
8695 for (signum = 0; signum < nsigs; signum++)
8698 signal_cache_update (-1);
8699 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
8700 target_program_signals ((int) GDB_SIGNAL_LAST, signal_program);
8704 /* Show the results. */
8705 sig_print_header ();
8706 for (; signum < nsigs; signum++)
8708 sig_print_info ((enum gdb_signal) signum);
8714 do_cleanups (old_chain);
8717 /* Complete the "handle" command. */
8719 static VEC (char_ptr) *
8720 handle_completer (struct cmd_list_element *ignore,
8721 const char *text, const char *word)
8723 VEC (char_ptr) *vec_signals, *vec_keywords, *return_val;
8724 static const char * const keywords[] =
8738 vec_signals = signal_completer (ignore, text, word);
8739 vec_keywords = complete_on_enum (keywords, word, word);
8741 return_val = VEC_merge (char_ptr, vec_signals, vec_keywords);
8742 VEC_free (char_ptr, vec_signals);
8743 VEC_free (char_ptr, vec_keywords);
8748 gdb_signal_from_command (int num)
8750 if (num >= 1 && num <= 15)
8751 return (enum gdb_signal) num;
8752 error (_("Only signals 1-15 are valid as numeric signals.\n\
8753 Use \"info signals\" for a list of symbolic signals."));
8756 /* Print current contents of the tables set by the handle command.
8757 It is possible we should just be printing signals actually used
8758 by the current target (but for things to work right when switching
8759 targets, all signals should be in the signal tables). */
8762 signals_info (char *signum_exp, int from_tty)
8764 enum gdb_signal oursig;
8766 sig_print_header ();
8770 /* First see if this is a symbol name. */
8771 oursig = gdb_signal_from_name (signum_exp);
8772 if (oursig == GDB_SIGNAL_UNKNOWN)
8774 /* No, try numeric. */
8776 gdb_signal_from_command (parse_and_eval_long (signum_exp));
8778 sig_print_info (oursig);
8782 printf_filtered ("\n");
8783 /* These ugly casts brought to you by the native VAX compiler. */
8784 for (oursig = GDB_SIGNAL_FIRST;
8785 (int) oursig < (int) GDB_SIGNAL_LAST;
8786 oursig = (enum gdb_signal) ((int) oursig + 1))
8790 if (oursig != GDB_SIGNAL_UNKNOWN
8791 && oursig != GDB_SIGNAL_DEFAULT && oursig != GDB_SIGNAL_0)
8792 sig_print_info (oursig);
8795 printf_filtered (_("\nUse the \"handle\" command "
8796 "to change these tables.\n"));
8799 /* The $_siginfo convenience variable is a bit special. We don't know
8800 for sure the type of the value until we actually have a chance to
8801 fetch the data. The type can change depending on gdbarch, so it is
8802 also dependent on which thread you have selected.
8804 1. making $_siginfo be an internalvar that creates a new value on
8807 2. making the value of $_siginfo be an lval_computed value. */
8809 /* This function implements the lval_computed support for reading a
8813 siginfo_value_read (struct value *v)
8815 LONGEST transferred;
8817 /* If we can access registers, so can we access $_siginfo. Likewise
8819 validate_registers_access ();
8822 target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO,
8824 value_contents_all_raw (v),
8826 TYPE_LENGTH (value_type (v)));
8828 if (transferred != TYPE_LENGTH (value_type (v)))
8829 error (_("Unable to read siginfo"));
8832 /* This function implements the lval_computed support for writing a
8836 siginfo_value_write (struct value *v, struct value *fromval)
8838 LONGEST transferred;
8840 /* If we can access registers, so can we access $_siginfo. Likewise
8842 validate_registers_access ();
8844 transferred = target_write (¤t_target,
8845 TARGET_OBJECT_SIGNAL_INFO,
8847 value_contents_all_raw (fromval),
8849 TYPE_LENGTH (value_type (fromval)));
8851 if (transferred != TYPE_LENGTH (value_type (fromval)))
8852 error (_("Unable to write siginfo"));
8855 static const struct lval_funcs siginfo_value_funcs =
8861 /* Return a new value with the correct type for the siginfo object of
8862 the current thread using architecture GDBARCH. Return a void value
8863 if there's no object available. */
8865 static struct value *
8866 siginfo_make_value (struct gdbarch *gdbarch, struct internalvar *var,
8869 if (target_has_stack
8870 && !ptid_equal (inferior_ptid, null_ptid)
8871 && gdbarch_get_siginfo_type_p (gdbarch))
8873 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8875 return allocate_computed_value (type, &siginfo_value_funcs, NULL);
8878 return allocate_value (builtin_type (gdbarch)->builtin_void);
8882 /* infcall_suspend_state contains state about the program itself like its
8883 registers and any signal it received when it last stopped.
8884 This state must be restored regardless of how the inferior function call
8885 ends (either successfully, or after it hits a breakpoint or signal)
8886 if the program is to properly continue where it left off. */
8888 struct infcall_suspend_state
8890 struct thread_suspend_state thread_suspend;
8894 struct regcache *registers;
8896 /* Format of SIGINFO_DATA or NULL if it is not present. */
8897 struct gdbarch *siginfo_gdbarch;
8899 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8900 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8901 content would be invalid. */
8902 gdb_byte *siginfo_data;
8905 struct infcall_suspend_state *
8906 save_infcall_suspend_state (void)
8908 struct infcall_suspend_state *inf_state;
8909 struct thread_info *tp = inferior_thread ();
8910 struct regcache *regcache = get_current_regcache ();
8911 struct gdbarch *gdbarch = get_regcache_arch (regcache);
8912 gdb_byte *siginfo_data = NULL;
8914 if (gdbarch_get_siginfo_type_p (gdbarch))
8916 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8917 size_t len = TYPE_LENGTH (type);
8918 struct cleanup *back_to;
8920 siginfo_data = (gdb_byte *) xmalloc (len);
8921 back_to = make_cleanup (xfree, siginfo_data);
8923 if (target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
8924 siginfo_data, 0, len) == len)
8925 discard_cleanups (back_to);
8928 /* Errors ignored. */
8929 do_cleanups (back_to);
8930 siginfo_data = NULL;
8934 inf_state = XCNEW (struct infcall_suspend_state);
8938 inf_state->siginfo_gdbarch = gdbarch;
8939 inf_state->siginfo_data = siginfo_data;
8942 inf_state->thread_suspend = tp->suspend;
8944 /* run_inferior_call will not use the signal due to its `proceed' call with
8945 GDB_SIGNAL_0 anyway. */
8946 tp->suspend.stop_signal = GDB_SIGNAL_0;
8948 inf_state->stop_pc = stop_pc;
8950 inf_state->registers = regcache_dup (regcache);
8955 /* Restore inferior session state to INF_STATE. */
8958 restore_infcall_suspend_state (struct infcall_suspend_state *inf_state)
8960 struct thread_info *tp = inferior_thread ();
8961 struct regcache *regcache = get_current_regcache ();
8962 struct gdbarch *gdbarch = get_regcache_arch (regcache);
8964 tp->suspend = inf_state->thread_suspend;
8966 stop_pc = inf_state->stop_pc;
8968 if (inf_state->siginfo_gdbarch == gdbarch)
8970 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8972 /* Errors ignored. */
8973 target_write (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
8974 inf_state->siginfo_data, 0, TYPE_LENGTH (type));
8977 /* The inferior can be gone if the user types "print exit(0)"
8978 (and perhaps other times). */
8979 if (target_has_execution)
8980 /* NB: The register write goes through to the target. */
8981 regcache_cpy (regcache, inf_state->registers);
8983 discard_infcall_suspend_state (inf_state);
8987 do_restore_infcall_suspend_state_cleanup (void *state)
8989 restore_infcall_suspend_state ((struct infcall_suspend_state *) state);
8993 make_cleanup_restore_infcall_suspend_state
8994 (struct infcall_suspend_state *inf_state)
8996 return make_cleanup (do_restore_infcall_suspend_state_cleanup, inf_state);
9000 discard_infcall_suspend_state (struct infcall_suspend_state *inf_state)
9002 regcache_xfree (inf_state->registers);
9003 xfree (inf_state->siginfo_data);
9008 get_infcall_suspend_state_regcache (struct infcall_suspend_state *inf_state)
9010 return inf_state->registers;
9013 /* infcall_control_state contains state regarding gdb's control of the
9014 inferior itself like stepping control. It also contains session state like
9015 the user's currently selected frame. */
9017 struct infcall_control_state
9019 struct thread_control_state thread_control;
9020 struct inferior_control_state inferior_control;
9023 enum stop_stack_kind stop_stack_dummy;
9024 int stopped_by_random_signal;
9026 /* ID if the selected frame when the inferior function call was made. */
9027 struct frame_id selected_frame_id;
9030 /* Save all of the information associated with the inferior<==>gdb
9033 struct infcall_control_state *
9034 save_infcall_control_state (void)
9036 struct infcall_control_state *inf_status =
9037 XNEW (struct infcall_control_state);
9038 struct thread_info *tp = inferior_thread ();
9039 struct inferior *inf = current_inferior ();
9041 inf_status->thread_control = tp->control;
9042 inf_status->inferior_control = inf->control;
9044 tp->control.step_resume_breakpoint = NULL;
9045 tp->control.exception_resume_breakpoint = NULL;
9047 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9048 chain. If caller's caller is walking the chain, they'll be happier if we
9049 hand them back the original chain when restore_infcall_control_state is
9051 tp->control.stop_bpstat = bpstat_copy (tp->control.stop_bpstat);
9054 inf_status->stop_stack_dummy = stop_stack_dummy;
9055 inf_status->stopped_by_random_signal = stopped_by_random_signal;
9057 inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL));
9063 restore_selected_frame (void *args)
9065 struct frame_id *fid = (struct frame_id *) args;
9066 struct frame_info *frame;
9068 frame = frame_find_by_id (*fid);
9070 /* If inf_status->selected_frame_id is NULL, there was no previously
9074 warning (_("Unable to restore previously selected frame."));
9078 select_frame (frame);
9083 /* Restore inferior session state to INF_STATUS. */
9086 restore_infcall_control_state (struct infcall_control_state *inf_status)
9088 struct thread_info *tp = inferior_thread ();
9089 struct inferior *inf = current_inferior ();
9091 if (tp->control.step_resume_breakpoint)
9092 tp->control.step_resume_breakpoint->disposition = disp_del_at_next_stop;
9094 if (tp->control.exception_resume_breakpoint)
9095 tp->control.exception_resume_breakpoint->disposition
9096 = disp_del_at_next_stop;
9098 /* Handle the bpstat_copy of the chain. */
9099 bpstat_clear (&tp->control.stop_bpstat);
9101 tp->control = inf_status->thread_control;
9102 inf->control = inf_status->inferior_control;
9105 stop_stack_dummy = inf_status->stop_stack_dummy;
9106 stopped_by_random_signal = inf_status->stopped_by_random_signal;
9108 if (target_has_stack)
9110 /* The point of catch_errors is that if the stack is clobbered,
9111 walking the stack might encounter a garbage pointer and
9112 error() trying to dereference it. */
9114 (restore_selected_frame, &inf_status->selected_frame_id,
9115 "Unable to restore previously selected frame:\n",
9116 RETURN_MASK_ERROR) == 0)
9117 /* Error in restoring the selected frame. Select the innermost
9119 select_frame (get_current_frame ());
9126 do_restore_infcall_control_state_cleanup (void *sts)
9128 restore_infcall_control_state ((struct infcall_control_state *) sts);
9132 make_cleanup_restore_infcall_control_state
9133 (struct infcall_control_state *inf_status)
9135 return make_cleanup (do_restore_infcall_control_state_cleanup, inf_status);
9139 discard_infcall_control_state (struct infcall_control_state *inf_status)
9141 if (inf_status->thread_control.step_resume_breakpoint)
9142 inf_status->thread_control.step_resume_breakpoint->disposition
9143 = disp_del_at_next_stop;
9145 if (inf_status->thread_control.exception_resume_breakpoint)
9146 inf_status->thread_control.exception_resume_breakpoint->disposition
9147 = disp_del_at_next_stop;
9149 /* See save_infcall_control_state for info on stop_bpstat. */
9150 bpstat_clear (&inf_status->thread_control.stop_bpstat);
9155 /* restore_inferior_ptid() will be used by the cleanup machinery
9156 to restore the inferior_ptid value saved in a call to
9157 save_inferior_ptid(). */
9160 restore_inferior_ptid (void *arg)
9162 ptid_t *saved_ptid_ptr = (ptid_t *) arg;
9164 inferior_ptid = *saved_ptid_ptr;
9168 /* Save the value of inferior_ptid so that it may be restored by a
9169 later call to do_cleanups(). Returns the struct cleanup pointer
9170 needed for later doing the cleanup. */
9173 save_inferior_ptid (void)
9175 ptid_t *saved_ptid_ptr = XNEW (ptid_t);
9177 *saved_ptid_ptr = inferior_ptid;
9178 return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
9184 clear_exit_convenience_vars (void)
9186 clear_internalvar (lookup_internalvar ("_exitsignal"));
9187 clear_internalvar (lookup_internalvar ("_exitcode"));
9191 /* User interface for reverse debugging:
9192 Set exec-direction / show exec-direction commands
9193 (returns error unless target implements to_set_exec_direction method). */
9195 enum exec_direction_kind execution_direction = EXEC_FORWARD;
9196 static const char exec_forward[] = "forward";
9197 static const char exec_reverse[] = "reverse";
9198 static const char *exec_direction = exec_forward;
9199 static const char *const exec_direction_names[] = {
9206 set_exec_direction_func (char *args, int from_tty,
9207 struct cmd_list_element *cmd)
9209 if (target_can_execute_reverse)
9211 if (!strcmp (exec_direction, exec_forward))
9212 execution_direction = EXEC_FORWARD;
9213 else if (!strcmp (exec_direction, exec_reverse))
9214 execution_direction = EXEC_REVERSE;
9218 exec_direction = exec_forward;
9219 error (_("Target does not support this operation."));
9224 show_exec_direction_func (struct ui_file *out, int from_tty,
9225 struct cmd_list_element *cmd, const char *value)
9227 switch (execution_direction) {
9229 fprintf_filtered (out, _("Forward.\n"));
9232 fprintf_filtered (out, _("Reverse.\n"));
9235 internal_error (__FILE__, __LINE__,
9236 _("bogus execution_direction value: %d"),
9237 (int) execution_direction);
9242 show_schedule_multiple (struct ui_file *file, int from_tty,
9243 struct cmd_list_element *c, const char *value)
9245 fprintf_filtered (file, _("Resuming the execution of threads "
9246 "of all processes is %s.\n"), value);
9249 /* Implementation of `siginfo' variable. */
9251 static const struct internalvar_funcs siginfo_funcs =
9258 /* Callback for infrun's target events source. This is marked when a
9259 thread has a pending status to process. */
9262 infrun_async_inferior_event_handler (gdb_client_data data)
9264 inferior_event_handler (INF_REG_EVENT, NULL);
9268 _initialize_infrun (void)
9272 struct cmd_list_element *c;
9274 /* Register extra event sources in the event loop. */
9275 infrun_async_inferior_event_token
9276 = create_async_event_handler (infrun_async_inferior_event_handler, NULL);
9278 add_info ("signals", signals_info, _("\
9279 What debugger does when program gets various signals.\n\
9280 Specify a signal as argument to print info on that signal only."));
9281 add_info_alias ("handle", "signals", 0);
9283 c = add_com ("handle", class_run, handle_command, _("\
9284 Specify how to handle signals.\n\
9285 Usage: handle SIGNAL [ACTIONS]\n\
9286 Args are signals and actions to apply to those signals.\n\
9287 If no actions are specified, the current settings for the specified signals\n\
9288 will be displayed instead.\n\
9290 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9291 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9292 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9293 The special arg \"all\" is recognized to mean all signals except those\n\
9294 used by the debugger, typically SIGTRAP and SIGINT.\n\
9296 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9297 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9298 Stop means reenter debugger if this signal happens (implies print).\n\
9299 Print means print a message if this signal happens.\n\
9300 Pass means let program see this signal; otherwise program doesn't know.\n\
9301 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9302 Pass and Stop may be combined.\n\
9304 Multiple signals may be specified. Signal numbers and signal names\n\
9305 may be interspersed with actions, with the actions being performed for\n\
9306 all signals cumulatively specified."));
9307 set_cmd_completer (c, handle_completer);
9310 stop_command = add_cmd ("stop", class_obscure,
9311 not_just_help_class_command, _("\
9312 There is no `stop' command, but you can set a hook on `stop'.\n\
9313 This allows you to set a list of commands to be run each time execution\n\
9314 of the program stops."), &cmdlist);
9316 add_setshow_zuinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\
9317 Set inferior debugging."), _("\
9318 Show inferior debugging."), _("\
9319 When non-zero, inferior specific debugging is enabled."),
9322 &setdebuglist, &showdebuglist);
9324 add_setshow_boolean_cmd ("displaced", class_maintenance,
9325 &debug_displaced, _("\
9326 Set displaced stepping debugging."), _("\
9327 Show displaced stepping debugging."), _("\
9328 When non-zero, displaced stepping specific debugging is enabled."),
9330 show_debug_displaced,
9331 &setdebuglist, &showdebuglist);
9333 add_setshow_boolean_cmd ("non-stop", no_class,
9335 Set whether gdb controls the inferior in non-stop mode."), _("\
9336 Show whether gdb controls the inferior in non-stop mode."), _("\
9337 When debugging a multi-threaded program and this setting is\n\
9338 off (the default, also called all-stop mode), when one thread stops\n\
9339 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9340 all other threads in the program while you interact with the thread of\n\
9341 interest. When you continue or step a thread, you can allow the other\n\
9342 threads to run, or have them remain stopped, but while you inspect any\n\
9343 thread's state, all threads stop.\n\
9345 In non-stop mode, when one thread stops, other threads can continue\n\
9346 to run freely. You'll be able to step each thread independently,\n\
9347 leave it stopped or free to run as needed."),
9353 numsigs = (int) GDB_SIGNAL_LAST;
9354 signal_stop = XNEWVEC (unsigned char, numsigs);
9355 signal_print = XNEWVEC (unsigned char, numsigs);
9356 signal_program = XNEWVEC (unsigned char, numsigs);
9357 signal_catch = XNEWVEC (unsigned char, numsigs);
9358 signal_pass = XNEWVEC (unsigned char, numsigs);
9359 for (i = 0; i < numsigs; i++)
9362 signal_print[i] = 1;
9363 signal_program[i] = 1;
9364 signal_catch[i] = 0;
9367 /* Signals caused by debugger's own actions should not be given to
9368 the program afterwards.
9370 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9371 explicitly specifies that it should be delivered to the target
9372 program. Typically, that would occur when a user is debugging a
9373 target monitor on a simulator: the target monitor sets a
9374 breakpoint; the simulator encounters this breakpoint and halts
9375 the simulation handing control to GDB; GDB, noting that the stop
9376 address doesn't map to any known breakpoint, returns control back
9377 to the simulator; the simulator then delivers the hardware
9378 equivalent of a GDB_SIGNAL_TRAP to the program being
9380 signal_program[GDB_SIGNAL_TRAP] = 0;
9381 signal_program[GDB_SIGNAL_INT] = 0;
9383 /* Signals that are not errors should not normally enter the debugger. */
9384 signal_stop[GDB_SIGNAL_ALRM] = 0;
9385 signal_print[GDB_SIGNAL_ALRM] = 0;
9386 signal_stop[GDB_SIGNAL_VTALRM] = 0;
9387 signal_print[GDB_SIGNAL_VTALRM] = 0;
9388 signal_stop[GDB_SIGNAL_PROF] = 0;
9389 signal_print[GDB_SIGNAL_PROF] = 0;
9390 signal_stop[GDB_SIGNAL_CHLD] = 0;
9391 signal_print[GDB_SIGNAL_CHLD] = 0;
9392 signal_stop[GDB_SIGNAL_IO] = 0;
9393 signal_print[GDB_SIGNAL_IO] = 0;
9394 signal_stop[GDB_SIGNAL_POLL] = 0;
9395 signal_print[GDB_SIGNAL_POLL] = 0;
9396 signal_stop[GDB_SIGNAL_URG] = 0;
9397 signal_print[GDB_SIGNAL_URG] = 0;
9398 signal_stop[GDB_SIGNAL_WINCH] = 0;
9399 signal_print[GDB_SIGNAL_WINCH] = 0;
9400 signal_stop[GDB_SIGNAL_PRIO] = 0;
9401 signal_print[GDB_SIGNAL_PRIO] = 0;
9403 /* These signals are used internally by user-level thread
9404 implementations. (See signal(5) on Solaris.) Like the above
9405 signals, a healthy program receives and handles them as part of
9406 its normal operation. */
9407 signal_stop[GDB_SIGNAL_LWP] = 0;
9408 signal_print[GDB_SIGNAL_LWP] = 0;
9409 signal_stop[GDB_SIGNAL_WAITING] = 0;
9410 signal_print[GDB_SIGNAL_WAITING] = 0;
9411 signal_stop[GDB_SIGNAL_CANCEL] = 0;
9412 signal_print[GDB_SIGNAL_CANCEL] = 0;
9413 signal_stop[GDB_SIGNAL_LIBRT] = 0;
9414 signal_print[GDB_SIGNAL_LIBRT] = 0;
9416 /* Update cached state. */
9417 signal_cache_update (-1);
9419 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support,
9420 &stop_on_solib_events, _("\
9421 Set stopping for shared library events."), _("\
9422 Show stopping for shared library events."), _("\
9423 If nonzero, gdb will give control to the user when the dynamic linker\n\
9424 notifies gdb of shared library events. The most common event of interest\n\
9425 to the user would be loading/unloading of a new library."),
9426 set_stop_on_solib_events,
9427 show_stop_on_solib_events,
9428 &setlist, &showlist);
9430 add_setshow_enum_cmd ("follow-fork-mode", class_run,
9431 follow_fork_mode_kind_names,
9432 &follow_fork_mode_string, _("\
9433 Set debugger response to a program call of fork or vfork."), _("\
9434 Show debugger response to a program call of fork or vfork."), _("\
9435 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9436 parent - the original process is debugged after a fork\n\
9437 child - the new process is debugged after a fork\n\
9438 The unfollowed process will continue to run.\n\
9439 By default, the debugger will follow the parent process."),
9441 show_follow_fork_mode_string,
9442 &setlist, &showlist);
9444 add_setshow_enum_cmd ("follow-exec-mode", class_run,
9445 follow_exec_mode_names,
9446 &follow_exec_mode_string, _("\
9447 Set debugger response to a program call of exec."), _("\
9448 Show debugger response to a program call of exec."), _("\
9449 An exec call replaces the program image of a process.\n\
9451 follow-exec-mode can be:\n\
9453 new - the debugger creates a new inferior and rebinds the process\n\
9454 to this new inferior. The program the process was running before\n\
9455 the exec call can be restarted afterwards by restarting the original\n\
9458 same - the debugger keeps the process bound to the same inferior.\n\
9459 The new executable image replaces the previous executable loaded in\n\
9460 the inferior. Restarting the inferior after the exec call restarts\n\
9461 the executable the process was running after the exec call.\n\
9463 By default, the debugger will use the same inferior."),
9465 show_follow_exec_mode_string,
9466 &setlist, &showlist);
9468 add_setshow_enum_cmd ("scheduler-locking", class_run,
9469 scheduler_enums, &scheduler_mode, _("\
9470 Set mode for locking scheduler during execution."), _("\
9471 Show mode for locking scheduler during execution."), _("\
9472 off == no locking (threads may preempt at any time)\n\
9473 on == full locking (no thread except the current thread may run)\n\
9474 This applies to both normal execution and replay mode.\n\
9475 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9476 In this mode, other threads may run during other commands.\n\
9477 This applies to both normal execution and replay mode.\n\
9478 replay == scheduler locked in replay mode and unlocked during normal execution."),
9479 set_schedlock_func, /* traps on target vector */
9480 show_scheduler_mode,
9481 &setlist, &showlist);
9483 add_setshow_boolean_cmd ("schedule-multiple", class_run, &sched_multi, _("\
9484 Set mode for resuming threads of all processes."), _("\
9485 Show mode for resuming threads of all processes."), _("\
9486 When on, execution commands (such as 'continue' or 'next') resume all\n\
9487 threads of all processes. When off (which is the default), execution\n\
9488 commands only resume the threads of the current process. The set of\n\
9489 threads that are resumed is further refined by the scheduler-locking\n\
9490 mode (see help set scheduler-locking)."),
9492 show_schedule_multiple,
9493 &setlist, &showlist);
9495 add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\
9496 Set mode of the step operation."), _("\
9497 Show mode of the step operation."), _("\
9498 When set, doing a step over a function without debug line information\n\
9499 will stop at the first instruction of that function. Otherwise, the\n\
9500 function is skipped and the step command stops at a different source line."),
9502 show_step_stop_if_no_debug,
9503 &setlist, &showlist);
9505 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run,
9506 &can_use_displaced_stepping, _("\
9507 Set debugger's willingness to use displaced stepping."), _("\
9508 Show debugger's willingness to use displaced stepping."), _("\
9509 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9510 supported by the target architecture. If off, gdb will not use displaced\n\
9511 stepping to step over breakpoints, even if such is supported by the target\n\
9512 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9513 if the target architecture supports it and non-stop mode is active, but will not\n\
9514 use it in all-stop mode (see help set non-stop)."),
9516 show_can_use_displaced_stepping,
9517 &setlist, &showlist);
9519 add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names,
9520 &exec_direction, _("Set direction of execution.\n\
9521 Options are 'forward' or 'reverse'."),
9522 _("Show direction of execution (forward/reverse)."),
9523 _("Tells gdb whether to execute forward or backward."),
9524 set_exec_direction_func, show_exec_direction_func,
9525 &setlist, &showlist);
9527 /* Set/show detach-on-fork: user-settable mode. */
9529 add_setshow_boolean_cmd ("detach-on-fork", class_run, &detach_fork, _("\
9530 Set whether gdb will detach the child of a fork."), _("\
9531 Show whether gdb will detach the child of a fork."), _("\
9532 Tells gdb whether to detach the child of a fork."),
9533 NULL, NULL, &setlist, &showlist);
9535 /* Set/show disable address space randomization mode. */
9537 add_setshow_boolean_cmd ("disable-randomization", class_support,
9538 &disable_randomization, _("\
9539 Set disabling of debuggee's virtual address space randomization."), _("\
9540 Show disabling of debuggee's virtual address space randomization."), _("\
9541 When this mode is on (which is the default), randomization of the virtual\n\
9542 address space is disabled. Standalone programs run with the randomization\n\
9543 enabled by default on some platforms."),
9544 &set_disable_randomization,
9545 &show_disable_randomization,
9546 &setlist, &showlist);
9548 /* ptid initializations */
9549 inferior_ptid = null_ptid;
9550 target_last_wait_ptid = minus_one_ptid;
9552 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed);
9553 observer_attach_thread_stop_requested (infrun_thread_stop_requested);
9554 observer_attach_thread_exit (infrun_thread_thread_exit);
9555 observer_attach_inferior_exit (infrun_inferior_exit);
9557 /* Explicitly create without lookup, since that tries to create a
9558 value with a void typed value, and when we get here, gdbarch
9559 isn't initialized yet. At this point, we're quite sure there
9560 isn't another convenience variable of the same name. */
9561 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs, NULL);
9563 add_setshow_boolean_cmd ("observer", no_class,
9564 &observer_mode_1, _("\
9565 Set whether gdb controls the inferior in observer mode."), _("\
9566 Show whether gdb controls the inferior in observer mode."), _("\
9567 In observer mode, GDB can get data from the inferior, but not\n\
9568 affect its execution. Registers and memory may not be changed,\n\
9569 breakpoints may not be set, and the program cannot be interrupted\n\