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 SWITCH_THRU_ALL_UIS ()
3862 check_curr_ui_sync_execution_done ();
3869 all_uis_on_sync_execution_starting (void)
3871 SWITCH_THRU_ALL_UIS ()
3873 if (current_ui->prompt_state == PROMPT_NEEDED)
3874 async_disable_stdin ();
3878 /* Asynchronous version of wait_for_inferior. It is called by the
3879 event loop whenever a change of state is detected on the file
3880 descriptor corresponding to the target. It can be called more than
3881 once to complete a single execution command. In such cases we need
3882 to keep the state in a global variable ECSS. If it is the last time
3883 that this function is called for a single execution command, then
3884 report to the user that the inferior has stopped, and do the
3885 necessary cleanups. */
3888 fetch_inferior_event (void *client_data)
3890 struct execution_control_state ecss;
3891 struct execution_control_state *ecs = &ecss;
3892 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
3893 struct cleanup *ts_old_chain;
3895 ptid_t waiton_ptid = minus_one_ptid;
3897 memset (ecs, 0, sizeof (*ecs));
3899 /* Events are always processed with the main UI as current UI. This
3900 way, warnings, debug output, etc. are always consistently sent to
3901 the main console. */
3902 scoped_restore save_ui = make_scoped_restore (¤t_ui, main_ui);
3904 /* End up with readline processing input, if necessary. */
3905 make_cleanup (reinstall_readline_callback_handler_cleanup, NULL);
3907 /* We're handling a live event, so make sure we're doing live
3908 debugging. If we're looking at traceframes while the target is
3909 running, we're going to need to get back to that mode after
3910 handling the event. */
3913 make_cleanup_restore_current_traceframe ();
3914 set_current_traceframe (-1);
3918 /* In non-stop mode, the user/frontend should not notice a thread
3919 switch due to internal events. Make sure we reverse to the
3920 user selected thread and frame after handling the event and
3921 running any breakpoint commands. */
3922 make_cleanup_restore_current_thread ();
3924 overlay_cache_invalid = 1;
3925 /* Flush target cache before starting to handle each event. Target
3926 was running and cache could be stale. This is just a heuristic.
3927 Running threads may modify target memory, but we don't get any
3929 target_dcache_invalidate ();
3931 scoped_restore save_exec_dir
3932 = make_scoped_restore (&execution_direction, target_execution_direction ());
3934 ecs->ptid = do_target_wait (waiton_ptid, &ecs->ws,
3935 target_can_async_p () ? TARGET_WNOHANG : 0);
3938 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
3940 /* If an error happens while handling the event, propagate GDB's
3941 knowledge of the executing state to the frontend/user running
3943 if (!target_is_non_stop_p ())
3944 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
3946 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &ecs->ptid);
3948 /* Get executed before make_cleanup_restore_current_thread above to apply
3949 still for the thread which has thrown the exception. */
3950 make_bpstat_clear_actions_cleanup ();
3952 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup, NULL);
3954 /* Now figure out what to do with the result of the result. */
3955 handle_inferior_event (ecs);
3957 if (!ecs->wait_some_more)
3959 struct inferior *inf = find_inferior_ptid (ecs->ptid);
3960 int should_stop = 1;
3961 struct thread_info *thr = ecs->event_thread;
3962 int should_notify_stop = 1;
3964 delete_just_stopped_threads_infrun_breakpoints ();
3968 struct thread_fsm *thread_fsm = thr->thread_fsm;
3970 if (thread_fsm != NULL)
3971 should_stop = thread_fsm_should_stop (thread_fsm, thr);
3980 clean_up_just_stopped_threads_fsms (ecs);
3982 if (thr != NULL && thr->thread_fsm != NULL)
3985 = thread_fsm_should_notify_stop (thr->thread_fsm);
3988 if (should_notify_stop)
3992 /* We may not find an inferior if this was a process exit. */
3993 if (inf == NULL || inf->control.stop_soon == NO_STOP_QUIETLY)
3994 proceeded = normal_stop ();
3998 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
4005 /* No error, don't finish the thread states yet. */
4006 discard_cleanups (ts_old_chain);
4008 /* Revert thread and frame. */
4009 do_cleanups (old_chain);
4011 /* If a UI was in sync execution mode, and now isn't, restore its
4012 prompt (a synchronous execution command has finished, and we're
4013 ready for input). */
4014 all_uis_check_sync_execution_done ();
4017 && exec_done_display_p
4018 && (ptid_equal (inferior_ptid, null_ptid)
4019 || !is_running (inferior_ptid)))
4020 printf_unfiltered (_("completed.\n"));
4023 /* Record the frame and location we're currently stepping through. */
4025 set_step_info (struct frame_info *frame, struct symtab_and_line sal)
4027 struct thread_info *tp = inferior_thread ();
4029 tp->control.step_frame_id = get_frame_id (frame);
4030 tp->control.step_stack_frame_id = get_stack_frame_id (frame);
4032 tp->current_symtab = sal.symtab;
4033 tp->current_line = sal.line;
4036 /* Clear context switchable stepping state. */
4039 init_thread_stepping_state (struct thread_info *tss)
4041 tss->stepped_breakpoint = 0;
4042 tss->stepping_over_breakpoint = 0;
4043 tss->stepping_over_watchpoint = 0;
4044 tss->step_after_step_resume_breakpoint = 0;
4047 /* Set the cached copy of the last ptid/waitstatus. */
4050 set_last_target_status (ptid_t ptid, struct target_waitstatus status)
4052 target_last_wait_ptid = ptid;
4053 target_last_waitstatus = status;
4056 /* Return the cached copy of the last pid/waitstatus returned by
4057 target_wait()/deprecated_target_wait_hook(). The data is actually
4058 cached by handle_inferior_event(), which gets called immediately
4059 after target_wait()/deprecated_target_wait_hook(). */
4062 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
4064 *ptidp = target_last_wait_ptid;
4065 *status = target_last_waitstatus;
4069 nullify_last_target_wait_ptid (void)
4071 target_last_wait_ptid = minus_one_ptid;
4074 /* Switch thread contexts. */
4077 context_switch (ptid_t ptid)
4079 if (debug_infrun && !ptid_equal (ptid, inferior_ptid))
4081 fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ",
4082 target_pid_to_str (inferior_ptid));
4083 fprintf_unfiltered (gdb_stdlog, "to %s\n",
4084 target_pid_to_str (ptid));
4087 switch_to_thread (ptid);
4090 /* If the target can't tell whether we've hit breakpoints
4091 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4092 check whether that could have been caused by a breakpoint. If so,
4093 adjust the PC, per gdbarch_decr_pc_after_break. */
4096 adjust_pc_after_break (struct thread_info *thread,
4097 struct target_waitstatus *ws)
4099 struct regcache *regcache;
4100 struct gdbarch *gdbarch;
4101 struct address_space *aspace;
4102 CORE_ADDR breakpoint_pc, decr_pc;
4104 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4105 we aren't, just return.
4107 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4108 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4109 implemented by software breakpoints should be handled through the normal
4112 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4113 different signals (SIGILL or SIGEMT for instance), but it is less
4114 clear where the PC is pointing afterwards. It may not match
4115 gdbarch_decr_pc_after_break. I don't know any specific target that
4116 generates these signals at breakpoints (the code has been in GDB since at
4117 least 1992) so I can not guess how to handle them here.
4119 In earlier versions of GDB, a target with
4120 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4121 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4122 target with both of these set in GDB history, and it seems unlikely to be
4123 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4125 if (ws->kind != TARGET_WAITKIND_STOPPED)
4128 if (ws->value.sig != GDB_SIGNAL_TRAP)
4131 /* In reverse execution, when a breakpoint is hit, the instruction
4132 under it has already been de-executed. The reported PC always
4133 points at the breakpoint address, so adjusting it further would
4134 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4137 B1 0x08000000 : INSN1
4138 B2 0x08000001 : INSN2
4140 PC -> 0x08000003 : INSN4
4142 Say you're stopped at 0x08000003 as above. Reverse continuing
4143 from that point should hit B2 as below. Reading the PC when the
4144 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4145 been de-executed already.
4147 B1 0x08000000 : INSN1
4148 B2 PC -> 0x08000001 : INSN2
4152 We can't apply the same logic as for forward execution, because
4153 we would wrongly adjust the PC to 0x08000000, since there's a
4154 breakpoint at PC - 1. We'd then report a hit on B1, although
4155 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4157 if (execution_direction == EXEC_REVERSE)
4160 /* If the target can tell whether the thread hit a SW breakpoint,
4161 trust it. Targets that can tell also adjust the PC
4163 if (target_supports_stopped_by_sw_breakpoint ())
4166 /* Note that relying on whether a breakpoint is planted in memory to
4167 determine this can fail. E.g,. the breakpoint could have been
4168 removed since. Or the thread could have been told to step an
4169 instruction the size of a breakpoint instruction, and only
4170 _after_ was a breakpoint inserted at its address. */
4172 /* If this target does not decrement the PC after breakpoints, then
4173 we have nothing to do. */
4174 regcache = get_thread_regcache (thread->ptid);
4175 gdbarch = get_regcache_arch (regcache);
4177 decr_pc = gdbarch_decr_pc_after_break (gdbarch);
4181 aspace = get_regcache_aspace (regcache);
4183 /* Find the location where (if we've hit a breakpoint) the
4184 breakpoint would be. */
4185 breakpoint_pc = regcache_read_pc (regcache) - decr_pc;
4187 /* If the target can't tell whether a software breakpoint triggered,
4188 fallback to figuring it out based on breakpoints we think were
4189 inserted in the target, and on whether the thread was stepped or
4192 /* Check whether there actually is a software breakpoint inserted at
4195 If in non-stop mode, a race condition is possible where we've
4196 removed a breakpoint, but stop events for that breakpoint were
4197 already queued and arrive later. To suppress those spurious
4198 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4199 and retire them after a number of stop events are reported. Note
4200 this is an heuristic and can thus get confused. The real fix is
4201 to get the "stopped by SW BP and needs adjustment" info out of
4202 the target/kernel (and thus never reach here; see above). */
4203 if (software_breakpoint_inserted_here_p (aspace, breakpoint_pc)
4204 || (target_is_non_stop_p ()
4205 && moribund_breakpoint_here_p (aspace, breakpoint_pc)))
4207 struct cleanup *old_cleanups = make_cleanup (null_cleanup, NULL);
4209 if (record_full_is_used ())
4210 record_full_gdb_operation_disable_set ();
4212 /* When using hardware single-step, a SIGTRAP is reported for both
4213 a completed single-step and a software breakpoint. Need to
4214 differentiate between the two, as the latter needs adjusting
4215 but the former does not.
4217 The SIGTRAP can be due to a completed hardware single-step only if
4218 - we didn't insert software single-step breakpoints
4219 - this thread is currently being stepped
4221 If any of these events did not occur, we must have stopped due
4222 to hitting a software breakpoint, and have to back up to the
4225 As a special case, we could have hardware single-stepped a
4226 software breakpoint. In this case (prev_pc == breakpoint_pc),
4227 we also need to back up to the breakpoint address. */
4229 if (thread_has_single_step_breakpoints_set (thread)
4230 || !currently_stepping (thread)
4231 || (thread->stepped_breakpoint
4232 && thread->prev_pc == breakpoint_pc))
4233 regcache_write_pc (regcache, breakpoint_pc);
4235 do_cleanups (old_cleanups);
4240 stepped_in_from (struct frame_info *frame, struct frame_id step_frame_id)
4242 for (frame = get_prev_frame (frame);
4244 frame = get_prev_frame (frame))
4246 if (frame_id_eq (get_frame_id (frame), step_frame_id))
4248 if (get_frame_type (frame) != INLINE_FRAME)
4255 /* Auxiliary function that handles syscall entry/return events.
4256 It returns 1 if the inferior should keep going (and GDB
4257 should ignore the event), or 0 if the event deserves to be
4261 handle_syscall_event (struct execution_control_state *ecs)
4263 struct regcache *regcache;
4266 if (!ptid_equal (ecs->ptid, inferior_ptid))
4267 context_switch (ecs->ptid);
4269 regcache = get_thread_regcache (ecs->ptid);
4270 syscall_number = ecs->ws.value.syscall_number;
4271 stop_pc = regcache_read_pc (regcache);
4273 if (catch_syscall_enabled () > 0
4274 && catching_syscall_number (syscall_number) > 0)
4277 fprintf_unfiltered (gdb_stdlog, "infrun: syscall number = '%d'\n",
4280 ecs->event_thread->control.stop_bpstat
4281 = bpstat_stop_status (get_regcache_aspace (regcache),
4282 stop_pc, ecs->ptid, &ecs->ws);
4284 if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
4286 /* Catchpoint hit. */
4291 /* If no catchpoint triggered for this, then keep going. */
4296 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4299 fill_in_stop_func (struct gdbarch *gdbarch,
4300 struct execution_control_state *ecs)
4302 if (!ecs->stop_func_filled_in)
4304 /* Don't care about return value; stop_func_start and stop_func_name
4305 will both be 0 if it doesn't work. */
4306 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
4307 &ecs->stop_func_start, &ecs->stop_func_end);
4308 ecs->stop_func_start
4309 += gdbarch_deprecated_function_start_offset (gdbarch);
4311 if (gdbarch_skip_entrypoint_p (gdbarch))
4312 ecs->stop_func_start = gdbarch_skip_entrypoint (gdbarch,
4313 ecs->stop_func_start);
4315 ecs->stop_func_filled_in = 1;
4320 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4322 static enum stop_kind
4323 get_inferior_stop_soon (ptid_t ptid)
4325 struct inferior *inf = find_inferior_ptid (ptid);
4327 gdb_assert (inf != NULL);
4328 return inf->control.stop_soon;
4331 /* Wait for one event. Store the resulting waitstatus in WS, and
4332 return the event ptid. */
4335 wait_one (struct target_waitstatus *ws)
4338 ptid_t wait_ptid = minus_one_ptid;
4340 overlay_cache_invalid = 1;
4342 /* Flush target cache before starting to handle each event.
4343 Target was running and cache could be stale. This is just a
4344 heuristic. Running threads may modify target memory, but we
4345 don't get any event. */
4346 target_dcache_invalidate ();
4348 if (deprecated_target_wait_hook)
4349 event_ptid = deprecated_target_wait_hook (wait_ptid, ws, 0);
4351 event_ptid = target_wait (wait_ptid, ws, 0);
4354 print_target_wait_results (wait_ptid, event_ptid, ws);
4359 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4360 instead of the current thread. */
4361 #define THREAD_STOPPED_BY(REASON) \
4363 thread_stopped_by_ ## REASON (ptid_t ptid) \
4365 struct cleanup *old_chain; \
4368 old_chain = save_inferior_ptid (); \
4369 inferior_ptid = ptid; \
4371 res = target_stopped_by_ ## REASON (); \
4373 do_cleanups (old_chain); \
4378 /* Generate thread_stopped_by_watchpoint. */
4379 THREAD_STOPPED_BY (watchpoint)
4380 /* Generate thread_stopped_by_sw_breakpoint. */
4381 THREAD_STOPPED_BY (sw_breakpoint)
4382 /* Generate thread_stopped_by_hw_breakpoint. */
4383 THREAD_STOPPED_BY (hw_breakpoint)
4385 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4388 switch_to_thread_cleanup (void *ptid_p)
4390 ptid_t ptid = *(ptid_t *) ptid_p;
4392 switch_to_thread (ptid);
4395 /* Save the thread's event and stop reason to process it later. */
4398 save_waitstatus (struct thread_info *tp, struct target_waitstatus *ws)
4400 struct regcache *regcache;
4401 struct address_space *aspace;
4407 statstr = target_waitstatus_to_string (ws);
4408 fprintf_unfiltered (gdb_stdlog,
4409 "infrun: saving status %s for %d.%ld.%ld\n",
4411 ptid_get_pid (tp->ptid),
4412 ptid_get_lwp (tp->ptid),
4413 ptid_get_tid (tp->ptid));
4417 /* Record for later. */
4418 tp->suspend.waitstatus = *ws;
4419 tp->suspend.waitstatus_pending_p = 1;
4421 regcache = get_thread_regcache (tp->ptid);
4422 aspace = get_regcache_aspace (regcache);
4424 if (ws->kind == TARGET_WAITKIND_STOPPED
4425 && ws->value.sig == GDB_SIGNAL_TRAP)
4427 CORE_ADDR pc = regcache_read_pc (regcache);
4429 adjust_pc_after_break (tp, &tp->suspend.waitstatus);
4431 if (thread_stopped_by_watchpoint (tp->ptid))
4433 tp->suspend.stop_reason
4434 = TARGET_STOPPED_BY_WATCHPOINT;
4436 else if (target_supports_stopped_by_sw_breakpoint ()
4437 && thread_stopped_by_sw_breakpoint (tp->ptid))
4439 tp->suspend.stop_reason
4440 = TARGET_STOPPED_BY_SW_BREAKPOINT;
4442 else if (target_supports_stopped_by_hw_breakpoint ()
4443 && thread_stopped_by_hw_breakpoint (tp->ptid))
4445 tp->suspend.stop_reason
4446 = TARGET_STOPPED_BY_HW_BREAKPOINT;
4448 else if (!target_supports_stopped_by_hw_breakpoint ()
4449 && hardware_breakpoint_inserted_here_p (aspace,
4452 tp->suspend.stop_reason
4453 = TARGET_STOPPED_BY_HW_BREAKPOINT;
4455 else if (!target_supports_stopped_by_sw_breakpoint ()
4456 && software_breakpoint_inserted_here_p (aspace,
4459 tp->suspend.stop_reason
4460 = TARGET_STOPPED_BY_SW_BREAKPOINT;
4462 else if (!thread_has_single_step_breakpoints_set (tp)
4463 && currently_stepping (tp))
4465 tp->suspend.stop_reason
4466 = TARGET_STOPPED_BY_SINGLE_STEP;
4471 /* A cleanup that disables thread create/exit events. */
4474 disable_thread_events (void *arg)
4476 target_thread_events (0);
4482 stop_all_threads (void)
4484 /* We may need multiple passes to discover all threads. */
4488 struct cleanup *old_chain;
4490 gdb_assert (target_is_non_stop_p ());
4493 fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads\n");
4495 entry_ptid = inferior_ptid;
4496 old_chain = make_cleanup (switch_to_thread_cleanup, &entry_ptid);
4498 target_thread_events (1);
4499 make_cleanup (disable_thread_events, NULL);
4501 /* Request threads to stop, and then wait for the stops. Because
4502 threads we already know about can spawn more threads while we're
4503 trying to stop them, and we only learn about new threads when we
4504 update the thread list, do this in a loop, and keep iterating
4505 until two passes find no threads that need to be stopped. */
4506 for (pass = 0; pass < 2; pass++, iterations++)
4509 fprintf_unfiltered (gdb_stdlog,
4510 "infrun: stop_all_threads, pass=%d, "
4511 "iterations=%d\n", pass, iterations);
4515 struct target_waitstatus ws;
4517 struct thread_info *t;
4519 update_thread_list ();
4521 /* Go through all threads looking for threads that we need
4522 to tell the target to stop. */
4523 ALL_NON_EXITED_THREADS (t)
4527 /* If already stopping, don't request a stop again.
4528 We just haven't seen the notification yet. */
4529 if (!t->stop_requested)
4532 fprintf_unfiltered (gdb_stdlog,
4533 "infrun: %s executing, "
4535 target_pid_to_str (t->ptid));
4536 target_stop (t->ptid);
4537 t->stop_requested = 1;
4542 fprintf_unfiltered (gdb_stdlog,
4543 "infrun: %s executing, "
4544 "already stopping\n",
4545 target_pid_to_str (t->ptid));
4548 if (t->stop_requested)
4554 fprintf_unfiltered (gdb_stdlog,
4555 "infrun: %s not executing\n",
4556 target_pid_to_str (t->ptid));
4558 /* The thread may be not executing, but still be
4559 resumed with a pending status to process. */
4567 /* If we find new threads on the second iteration, restart
4568 over. We want to see two iterations in a row with all
4573 event_ptid = wait_one (&ws);
4574 if (ws.kind == TARGET_WAITKIND_NO_RESUMED)
4576 /* All resumed threads exited. */
4578 else if (ws.kind == TARGET_WAITKIND_THREAD_EXITED
4579 || ws.kind == TARGET_WAITKIND_EXITED
4580 || ws.kind == TARGET_WAITKIND_SIGNALLED)
4584 ptid_t ptid = pid_to_ptid (ws.value.integer);
4586 fprintf_unfiltered (gdb_stdlog,
4587 "infrun: %s exited while "
4588 "stopping threads\n",
4589 target_pid_to_str (ptid));
4594 struct inferior *inf;
4596 t = find_thread_ptid (event_ptid);
4598 t = add_thread (event_ptid);
4600 t->stop_requested = 0;
4603 t->control.may_range_step = 0;
4605 /* This may be the first time we see the inferior report
4607 inf = find_inferior_ptid (event_ptid);
4608 if (inf->needs_setup)
4610 switch_to_thread_no_regs (t);
4614 if (ws.kind == TARGET_WAITKIND_STOPPED
4615 && ws.value.sig == GDB_SIGNAL_0)
4617 /* We caught the event that we intended to catch, so
4618 there's no event pending. */
4619 t->suspend.waitstatus.kind = TARGET_WAITKIND_IGNORE;
4620 t->suspend.waitstatus_pending_p = 0;
4622 if (displaced_step_fixup (t->ptid, GDB_SIGNAL_0) < 0)
4624 /* Add it back to the step-over queue. */
4627 fprintf_unfiltered (gdb_stdlog,
4628 "infrun: displaced-step of %s "
4629 "canceled: adding back to the "
4630 "step-over queue\n",
4631 target_pid_to_str (t->ptid));
4633 t->control.trap_expected = 0;
4634 thread_step_over_chain_enqueue (t);
4639 enum gdb_signal sig;
4640 struct regcache *regcache;
4646 statstr = target_waitstatus_to_string (&ws);
4647 fprintf_unfiltered (gdb_stdlog,
4648 "infrun: target_wait %s, saving "
4649 "status for %d.%ld.%ld\n",
4651 ptid_get_pid (t->ptid),
4652 ptid_get_lwp (t->ptid),
4653 ptid_get_tid (t->ptid));
4657 /* Record for later. */
4658 save_waitstatus (t, &ws);
4660 sig = (ws.kind == TARGET_WAITKIND_STOPPED
4661 ? ws.value.sig : GDB_SIGNAL_0);
4663 if (displaced_step_fixup (t->ptid, sig) < 0)
4665 /* Add it back to the step-over queue. */
4666 t->control.trap_expected = 0;
4667 thread_step_over_chain_enqueue (t);
4670 regcache = get_thread_regcache (t->ptid);
4671 t->suspend.stop_pc = regcache_read_pc (regcache);
4675 fprintf_unfiltered (gdb_stdlog,
4676 "infrun: saved stop_pc=%s for %s "
4677 "(currently_stepping=%d)\n",
4678 paddress (target_gdbarch (),
4679 t->suspend.stop_pc),
4680 target_pid_to_str (t->ptid),
4681 currently_stepping (t));
4688 do_cleanups (old_chain);
4691 fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads done\n");
4694 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4697 handle_no_resumed (struct execution_control_state *ecs)
4699 struct inferior *inf;
4700 struct thread_info *thread;
4702 if (target_can_async_p ())
4709 if (ui->prompt_state == PROMPT_BLOCKED)
4717 /* There were no unwaited-for children left in the target, but,
4718 we're not synchronously waiting for events either. Just
4722 fprintf_unfiltered (gdb_stdlog,
4723 "infrun: TARGET_WAITKIND_NO_RESUMED "
4724 "(ignoring: bg)\n");
4725 prepare_to_wait (ecs);
4730 /* Otherwise, if we were running a synchronous execution command, we
4731 may need to cancel it and give the user back the terminal.
4733 In non-stop mode, the target can't tell whether we've already
4734 consumed previous stop events, so it can end up sending us a
4735 no-resumed event like so:
4737 #0 - thread 1 is left stopped
4739 #1 - thread 2 is resumed and hits breakpoint
4740 -> TARGET_WAITKIND_STOPPED
4742 #2 - thread 3 is resumed and exits
4743 this is the last resumed thread, so
4744 -> TARGET_WAITKIND_NO_RESUMED
4746 #3 - gdb processes stop for thread 2 and decides to re-resume
4749 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4750 thread 2 is now resumed, so the event should be ignored.
4752 IOW, if the stop for thread 2 doesn't end a foreground command,
4753 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4754 event. But it could be that the event meant that thread 2 itself
4755 (or whatever other thread was the last resumed thread) exited.
4757 To address this we refresh the thread list and check whether we
4758 have resumed threads _now_. In the example above, this removes
4759 thread 3 from the thread list. If thread 2 was re-resumed, we
4760 ignore this event. If we find no thread resumed, then we cancel
4761 the synchronous command show "no unwaited-for " to the user. */
4762 update_thread_list ();
4764 ALL_NON_EXITED_THREADS (thread)
4766 if (thread->executing
4767 || thread->suspend.waitstatus_pending_p)
4769 /* There were no unwaited-for children left in the target at
4770 some point, but there are now. Just ignore. */
4772 fprintf_unfiltered (gdb_stdlog,
4773 "infrun: TARGET_WAITKIND_NO_RESUMED "
4774 "(ignoring: found resumed)\n");
4775 prepare_to_wait (ecs);
4780 /* Note however that we may find no resumed thread because the whole
4781 process exited meanwhile (thus updating the thread list results
4782 in an empty thread list). In this case we know we'll be getting
4783 a process exit event shortly. */
4789 thread = any_live_thread_of_process (inf->pid);
4793 fprintf_unfiltered (gdb_stdlog,
4794 "infrun: TARGET_WAITKIND_NO_RESUMED "
4795 "(expect process exit)\n");
4796 prepare_to_wait (ecs);
4801 /* Go ahead and report the event. */
4805 /* Given an execution control state that has been freshly filled in by
4806 an event from the inferior, figure out what it means and take
4809 The alternatives are:
4811 1) stop_waiting and return; to really stop and return to the
4814 2) keep_going and return; to wait for the next event (set
4815 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4819 handle_inferior_event_1 (struct execution_control_state *ecs)
4821 enum stop_kind stop_soon;
4823 if (ecs->ws.kind == TARGET_WAITKIND_IGNORE)
4825 /* We had an event in the inferior, but we are not interested in
4826 handling it at this level. The lower layers have already
4827 done what needs to be done, if anything.
4829 One of the possible circumstances for this is when the
4830 inferior produces output for the console. The inferior has
4831 not stopped, and we are ignoring the event. Another possible
4832 circumstance is any event which the lower level knows will be
4833 reported multiple times without an intervening resume. */
4835 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n");
4836 prepare_to_wait (ecs);
4840 if (ecs->ws.kind == TARGET_WAITKIND_THREAD_EXITED)
4843 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4844 prepare_to_wait (ecs);
4848 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED
4849 && handle_no_resumed (ecs))
4852 /* Cache the last pid/waitstatus. */
4853 set_last_target_status (ecs->ptid, ecs->ws);
4855 /* Always clear state belonging to the previous time we stopped. */
4856 stop_stack_dummy = STOP_NONE;
4858 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED)
4860 /* No unwaited-for children left. IOW, all resumed children
4863 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4865 stop_print_frame = 0;
4870 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
4871 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
4873 ecs->event_thread = find_thread_ptid (ecs->ptid);
4874 /* If it's a new thread, add it to the thread database. */
4875 if (ecs->event_thread == NULL)
4876 ecs->event_thread = add_thread (ecs->ptid);
4878 /* Disable range stepping. If the next step request could use a
4879 range, this will be end up re-enabled then. */
4880 ecs->event_thread->control.may_range_step = 0;
4883 /* Dependent on valid ECS->EVENT_THREAD. */
4884 adjust_pc_after_break (ecs->event_thread, &ecs->ws);
4886 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4887 reinit_frame_cache ();
4889 breakpoint_retire_moribund ();
4891 /* First, distinguish signals caused by the debugger from signals
4892 that have to do with the program's own actions. Note that
4893 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4894 on the operating system version. Here we detect when a SIGILL or
4895 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4896 something similar for SIGSEGV, since a SIGSEGV will be generated
4897 when we're trying to execute a breakpoint instruction on a
4898 non-executable stack. This happens for call dummy breakpoints
4899 for architectures like SPARC that place call dummies on the
4901 if (ecs->ws.kind == TARGET_WAITKIND_STOPPED
4902 && (ecs->ws.value.sig == GDB_SIGNAL_ILL
4903 || ecs->ws.value.sig == GDB_SIGNAL_SEGV
4904 || ecs->ws.value.sig == GDB_SIGNAL_EMT))
4906 struct regcache *regcache = get_thread_regcache (ecs->ptid);
4908 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache),
4909 regcache_read_pc (regcache)))
4912 fprintf_unfiltered (gdb_stdlog,
4913 "infrun: Treating signal as SIGTRAP\n");
4914 ecs->ws.value.sig = GDB_SIGNAL_TRAP;
4918 /* Mark the non-executing threads accordingly. In all-stop, all
4919 threads of all processes are stopped when we get any event
4920 reported. In non-stop mode, only the event thread stops. */
4924 if (!target_is_non_stop_p ())
4925 mark_ptid = minus_one_ptid;
4926 else if (ecs->ws.kind == TARGET_WAITKIND_SIGNALLED
4927 || ecs->ws.kind == TARGET_WAITKIND_EXITED)
4929 /* If we're handling a process exit in non-stop mode, even
4930 though threads haven't been deleted yet, one would think
4931 that there is nothing to do, as threads of the dead process
4932 will be soon deleted, and threads of any other process were
4933 left running. However, on some targets, threads survive a
4934 process exit event. E.g., for the "checkpoint" command,
4935 when the current checkpoint/fork exits, linux-fork.c
4936 automatically switches to another fork from within
4937 target_mourn_inferior, by associating the same
4938 inferior/thread to another fork. We haven't mourned yet at
4939 this point, but we must mark any threads left in the
4940 process as not-executing so that finish_thread_state marks
4941 them stopped (in the user's perspective) if/when we present
4942 the stop to the user. */
4943 mark_ptid = pid_to_ptid (ptid_get_pid (ecs->ptid));
4946 mark_ptid = ecs->ptid;
4948 set_executing (mark_ptid, 0);
4950 /* Likewise the resumed flag. */
4951 set_resumed (mark_ptid, 0);
4954 switch (ecs->ws.kind)
4956 case TARGET_WAITKIND_LOADED:
4958 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n");
4959 if (!ptid_equal (ecs->ptid, inferior_ptid))
4960 context_switch (ecs->ptid);
4961 /* Ignore gracefully during startup of the inferior, as it might
4962 be the shell which has just loaded some objects, otherwise
4963 add the symbols for the newly loaded objects. Also ignore at
4964 the beginning of an attach or remote session; we will query
4965 the full list of libraries once the connection is
4968 stop_soon = get_inferior_stop_soon (ecs->ptid);
4969 if (stop_soon == NO_STOP_QUIETLY)
4971 struct regcache *regcache;
4973 regcache = get_thread_regcache (ecs->ptid);
4975 handle_solib_event ();
4977 ecs->event_thread->control.stop_bpstat
4978 = bpstat_stop_status (get_regcache_aspace (regcache),
4979 stop_pc, ecs->ptid, &ecs->ws);
4981 if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
4983 /* A catchpoint triggered. */
4984 process_event_stop_test (ecs);
4988 /* If requested, stop when the dynamic linker notifies
4989 gdb of events. This allows the user to get control
4990 and place breakpoints in initializer routines for
4991 dynamically loaded objects (among other things). */
4992 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
4993 if (stop_on_solib_events)
4995 /* Make sure we print "Stopped due to solib-event" in
4997 stop_print_frame = 1;
5004 /* If we are skipping through a shell, or through shared library
5005 loading that we aren't interested in, resume the program. If
5006 we're running the program normally, also resume. */
5007 if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY)
5009 /* Loading of shared libraries might have changed breakpoint
5010 addresses. Make sure new breakpoints are inserted. */
5011 if (stop_soon == NO_STOP_QUIETLY)
5012 insert_breakpoints ();
5013 resume (GDB_SIGNAL_0);
5014 prepare_to_wait (ecs);
5018 /* But stop if we're attaching or setting up a remote
5020 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
5021 || stop_soon == STOP_QUIETLY_REMOTE)
5024 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
5029 internal_error (__FILE__, __LINE__,
5030 _("unhandled stop_soon: %d"), (int) stop_soon);
5032 case TARGET_WAITKIND_SPURIOUS:
5034 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
5035 if (!ptid_equal (ecs->ptid, inferior_ptid))
5036 context_switch (ecs->ptid);
5037 resume (GDB_SIGNAL_0);
5038 prepare_to_wait (ecs);
5041 case TARGET_WAITKIND_THREAD_CREATED:
5043 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
5044 if (!ptid_equal (ecs->ptid, inferior_ptid))
5045 context_switch (ecs->ptid);
5046 if (!switch_back_to_stepped_thread (ecs))
5050 case TARGET_WAITKIND_EXITED:
5051 case TARGET_WAITKIND_SIGNALLED:
5054 if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
5055 fprintf_unfiltered (gdb_stdlog,
5056 "infrun: TARGET_WAITKIND_EXITED\n");
5058 fprintf_unfiltered (gdb_stdlog,
5059 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5062 inferior_ptid = ecs->ptid;
5063 set_current_inferior (find_inferior_ptid (ecs->ptid));
5064 set_current_program_space (current_inferior ()->pspace);
5065 handle_vfork_child_exec_or_exit (0);
5066 target_terminal_ours (); /* Must do this before mourn anyway. */
5068 /* Clearing any previous state of convenience variables. */
5069 clear_exit_convenience_vars ();
5071 if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
5073 /* Record the exit code in the convenience variable $_exitcode, so
5074 that the user can inspect this again later. */
5075 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5076 (LONGEST) ecs->ws.value.integer);
5078 /* Also record this in the inferior itself. */
5079 current_inferior ()->has_exit_code = 1;
5080 current_inferior ()->exit_code = (LONGEST) ecs->ws.value.integer;
5082 /* Support the --return-child-result option. */
5083 return_child_result_value = ecs->ws.value.integer;
5085 observer_notify_exited (ecs->ws.value.integer);
5089 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5090 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5092 if (gdbarch_gdb_signal_to_target_p (gdbarch))
5094 /* Set the value of the internal variable $_exitsignal,
5095 which holds the signal uncaught by the inferior. */
5096 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5097 gdbarch_gdb_signal_to_target (gdbarch,
5098 ecs->ws.value.sig));
5102 /* We don't have access to the target's method used for
5103 converting between signal numbers (GDB's internal
5104 representation <-> target's representation).
5105 Therefore, we cannot do a good job at displaying this
5106 information to the user. It's better to just warn
5107 her about it (if infrun debugging is enabled), and
5110 fprintf_filtered (gdb_stdlog, _("\
5111 Cannot fill $_exitsignal with the correct signal number.\n"));
5114 observer_notify_signal_exited (ecs->ws.value.sig);
5117 gdb_flush (gdb_stdout);
5118 target_mourn_inferior (inferior_ptid);
5119 stop_print_frame = 0;
5123 /* The following are the only cases in which we keep going;
5124 the above cases end in a continue or goto. */
5125 case TARGET_WAITKIND_FORKED:
5126 case TARGET_WAITKIND_VFORKED:
5129 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
5130 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
5132 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_VFORKED\n");
5135 /* Check whether the inferior is displaced stepping. */
5137 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5138 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5140 /* If checking displaced stepping is supported, and thread
5141 ecs->ptid is displaced stepping. */
5142 if (displaced_step_in_progress_thread (ecs->ptid))
5144 struct inferior *parent_inf
5145 = find_inferior_ptid (ecs->ptid);
5146 struct regcache *child_regcache;
5147 CORE_ADDR parent_pc;
5149 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5150 indicating that the displaced stepping of syscall instruction
5151 has been done. Perform cleanup for parent process here. Note
5152 that this operation also cleans up the child process for vfork,
5153 because their pages are shared. */
5154 displaced_step_fixup (ecs->ptid, GDB_SIGNAL_TRAP);
5155 /* Start a new step-over in another thread if there's one
5159 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
5161 struct displaced_step_inferior_state *displaced
5162 = get_displaced_stepping_state (ptid_get_pid (ecs->ptid));
5164 /* Restore scratch pad for child process. */
5165 displaced_step_restore (displaced, ecs->ws.value.related_pid);
5168 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5169 the child's PC is also within the scratchpad. Set the child's PC
5170 to the parent's PC value, which has already been fixed up.
5171 FIXME: we use the parent's aspace here, although we're touching
5172 the child, because the child hasn't been added to the inferior
5173 list yet at this point. */
5176 = get_thread_arch_aspace_regcache (ecs->ws.value.related_pid,
5178 parent_inf->aspace);
5179 /* Read PC value of parent process. */
5180 parent_pc = regcache_read_pc (regcache);
5182 if (debug_displaced)
5183 fprintf_unfiltered (gdb_stdlog,
5184 "displaced: write child pc from %s to %s\n",
5186 regcache_read_pc (child_regcache)),
5187 paddress (gdbarch, parent_pc));
5189 regcache_write_pc (child_regcache, parent_pc);
5193 if (!ptid_equal (ecs->ptid, inferior_ptid))
5194 context_switch (ecs->ptid);
5196 /* Immediately detach breakpoints from the child before there's
5197 any chance of letting the user delete breakpoints from the
5198 breakpoint lists. If we don't do this early, it's easy to
5199 leave left over traps in the child, vis: "break foo; catch
5200 fork; c; <fork>; del; c; <child calls foo>". We only follow
5201 the fork on the last `continue', and by that time the
5202 breakpoint at "foo" is long gone from the breakpoint table.
5203 If we vforked, then we don't need to unpatch here, since both
5204 parent and child are sharing the same memory pages; we'll
5205 need to unpatch at follow/detach time instead to be certain
5206 that new breakpoints added between catchpoint hit time and
5207 vfork follow are detached. */
5208 if (ecs->ws.kind != TARGET_WAITKIND_VFORKED)
5210 /* This won't actually modify the breakpoint list, but will
5211 physically remove the breakpoints from the child. */
5212 detach_breakpoints (ecs->ws.value.related_pid);
5215 delete_just_stopped_threads_single_step_breakpoints ();
5217 /* In case the event is caught by a catchpoint, remember that
5218 the event is to be followed at the next resume of the thread,
5219 and not immediately. */
5220 ecs->event_thread->pending_follow = ecs->ws;
5222 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5224 ecs->event_thread->control.stop_bpstat
5225 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5226 stop_pc, ecs->ptid, &ecs->ws);
5228 /* If no catchpoint triggered for this, then keep going. Note
5229 that we're interested in knowing the bpstat actually causes a
5230 stop, not just if it may explain the signal. Software
5231 watchpoints, for example, always appear in the bpstat. */
5232 if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
5238 = (follow_fork_mode_string == follow_fork_mode_child);
5240 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5242 should_resume = follow_fork ();
5245 child = ecs->ws.value.related_pid;
5247 /* At this point, the parent is marked running, and the
5248 child is marked stopped. */
5250 /* If not resuming the parent, mark it stopped. */
5251 if (follow_child && !detach_fork && !non_stop && !sched_multi)
5252 set_running (parent, 0);
5254 /* If resuming the child, mark it running. */
5255 if (follow_child || (!detach_fork && (non_stop || sched_multi)))
5256 set_running (child, 1);
5258 /* In non-stop mode, also resume the other branch. */
5259 if (!detach_fork && (non_stop
5260 || (sched_multi && target_is_non_stop_p ())))
5263 switch_to_thread (parent);
5265 switch_to_thread (child);
5267 ecs->event_thread = inferior_thread ();
5268 ecs->ptid = inferior_ptid;
5273 switch_to_thread (child);
5275 switch_to_thread (parent);
5277 ecs->event_thread = inferior_thread ();
5278 ecs->ptid = inferior_ptid;
5286 process_event_stop_test (ecs);
5289 case TARGET_WAITKIND_VFORK_DONE:
5290 /* Done with the shared memory region. Re-insert breakpoints in
5291 the parent, and keep going. */
5294 fprintf_unfiltered (gdb_stdlog,
5295 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5297 if (!ptid_equal (ecs->ptid, inferior_ptid))
5298 context_switch (ecs->ptid);
5300 current_inferior ()->waiting_for_vfork_done = 0;
5301 current_inferior ()->pspace->breakpoints_not_allowed = 0;
5302 /* This also takes care of reinserting breakpoints in the
5303 previously locked inferior. */
5307 case TARGET_WAITKIND_EXECD:
5309 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n");
5311 if (!ptid_equal (ecs->ptid, inferior_ptid))
5312 context_switch (ecs->ptid);
5314 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5316 /* Do whatever is necessary to the parent branch of the vfork. */
5317 handle_vfork_child_exec_or_exit (1);
5319 /* This causes the eventpoints and symbol table to be reset.
5320 Must do this now, before trying to determine whether to
5322 follow_exec (inferior_ptid, ecs->ws.value.execd_pathname);
5324 /* In follow_exec we may have deleted the original thread and
5325 created a new one. Make sure that the event thread is the
5326 execd thread for that case (this is a nop otherwise). */
5327 ecs->event_thread = inferior_thread ();
5329 ecs->event_thread->control.stop_bpstat
5330 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5331 stop_pc, ecs->ptid, &ecs->ws);
5333 /* Note that this may be referenced from inside
5334 bpstat_stop_status above, through inferior_has_execd. */
5335 xfree (ecs->ws.value.execd_pathname);
5336 ecs->ws.value.execd_pathname = NULL;
5338 /* If no catchpoint triggered for this, then keep going. */
5339 if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
5341 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5345 process_event_stop_test (ecs);
5348 /* Be careful not to try to gather much state about a thread
5349 that's in a syscall. It's frequently a losing proposition. */
5350 case TARGET_WAITKIND_SYSCALL_ENTRY:
5352 fprintf_unfiltered (gdb_stdlog,
5353 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5354 /* Getting the current syscall number. */
5355 if (handle_syscall_event (ecs) == 0)
5356 process_event_stop_test (ecs);
5359 /* Before examining the threads further, step this thread to
5360 get it entirely out of the syscall. (We get notice of the
5361 event when the thread is just on the verge of exiting a
5362 syscall. Stepping one instruction seems to get it back
5364 case TARGET_WAITKIND_SYSCALL_RETURN:
5366 fprintf_unfiltered (gdb_stdlog,
5367 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5368 if (handle_syscall_event (ecs) == 0)
5369 process_event_stop_test (ecs);
5372 case TARGET_WAITKIND_STOPPED:
5374 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n");
5375 ecs->event_thread->suspend.stop_signal = ecs->ws.value.sig;
5376 handle_signal_stop (ecs);
5379 case TARGET_WAITKIND_NO_HISTORY:
5381 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5382 /* Reverse execution: target ran out of history info. */
5384 /* Switch to the stopped thread. */
5385 if (!ptid_equal (ecs->ptid, inferior_ptid))
5386 context_switch (ecs->ptid);
5388 fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n");
5390 delete_just_stopped_threads_single_step_breakpoints ();
5391 stop_pc = regcache_read_pc (get_thread_regcache (inferior_ptid));
5392 observer_notify_no_history ();
5398 /* A wrapper around handle_inferior_event_1, which also makes sure
5399 that all temporary struct value objects that were created during
5400 the handling of the event get deleted at the end. */
5403 handle_inferior_event (struct execution_control_state *ecs)
5405 struct value *mark = value_mark ();
5407 handle_inferior_event_1 (ecs);
5408 /* Purge all temporary values created during the event handling,
5409 as it could be a long time before we return to the command level
5410 where such values would otherwise be purged. */
5411 value_free_to_mark (mark);
5414 /* Restart threads back to what they were trying to do back when we
5415 paused them for an in-line step-over. The EVENT_THREAD thread is
5419 restart_threads (struct thread_info *event_thread)
5421 struct thread_info *tp;
5423 /* In case the instruction just stepped spawned a new thread. */
5424 update_thread_list ();
5426 ALL_NON_EXITED_THREADS (tp)
5428 if (tp == event_thread)
5431 fprintf_unfiltered (gdb_stdlog,
5432 "infrun: restart threads: "
5433 "[%s] is event thread\n",
5434 target_pid_to_str (tp->ptid));
5438 if (!(tp->state == THREAD_RUNNING || tp->control.in_infcall))
5441 fprintf_unfiltered (gdb_stdlog,
5442 "infrun: restart threads: "
5443 "[%s] not meant to be running\n",
5444 target_pid_to_str (tp->ptid));
5451 fprintf_unfiltered (gdb_stdlog,
5452 "infrun: restart threads: [%s] resumed\n",
5453 target_pid_to_str (tp->ptid));
5454 gdb_assert (tp->executing || tp->suspend.waitstatus_pending_p);
5458 if (thread_is_in_step_over_chain (tp))
5461 fprintf_unfiltered (gdb_stdlog,
5462 "infrun: restart threads: "
5463 "[%s] needs step-over\n",
5464 target_pid_to_str (tp->ptid));
5465 gdb_assert (!tp->resumed);
5470 if (tp->suspend.waitstatus_pending_p)
5473 fprintf_unfiltered (gdb_stdlog,
5474 "infrun: restart threads: "
5475 "[%s] has pending status\n",
5476 target_pid_to_str (tp->ptid));
5481 /* If some thread needs to start a step-over at this point, it
5482 should still be in the step-over queue, and thus skipped
5484 if (thread_still_needs_step_over (tp))
5486 internal_error (__FILE__, __LINE__,
5487 "thread [%s] needs a step-over, but not in "
5488 "step-over queue\n",
5489 target_pid_to_str (tp->ptid));
5492 if (currently_stepping (tp))
5495 fprintf_unfiltered (gdb_stdlog,
5496 "infrun: restart threads: [%s] was stepping\n",
5497 target_pid_to_str (tp->ptid));
5498 keep_going_stepped_thread (tp);
5502 struct execution_control_state ecss;
5503 struct execution_control_state *ecs = &ecss;
5506 fprintf_unfiltered (gdb_stdlog,
5507 "infrun: restart threads: [%s] continuing\n",
5508 target_pid_to_str (tp->ptid));
5509 reset_ecs (ecs, tp);
5510 switch_to_thread (tp->ptid);
5511 keep_going_pass_signal (ecs);
5516 /* Callback for iterate_over_threads. Find a resumed thread that has
5517 a pending waitstatus. */
5520 resumed_thread_with_pending_status (struct thread_info *tp,
5524 && tp->suspend.waitstatus_pending_p);
5527 /* Called when we get an event that may finish an in-line or
5528 out-of-line (displaced stepping) step-over started previously.
5529 Return true if the event is processed and we should go back to the
5530 event loop; false if the caller should continue processing the
5534 finish_step_over (struct execution_control_state *ecs)
5536 int had_step_over_info;
5538 displaced_step_fixup (ecs->ptid,
5539 ecs->event_thread->suspend.stop_signal);
5541 had_step_over_info = step_over_info_valid_p ();
5543 if (had_step_over_info)
5545 /* If we're stepping over a breakpoint with all threads locked,
5546 then only the thread that was stepped should be reporting
5548 gdb_assert (ecs->event_thread->control.trap_expected);
5550 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
5551 clear_step_over_info ();
5554 if (!target_is_non_stop_p ())
5557 /* Start a new step-over in another thread if there's one that
5561 /* If we were stepping over a breakpoint before, and haven't started
5562 a new in-line step-over sequence, then restart all other threads
5563 (except the event thread). We can't do this in all-stop, as then
5564 e.g., we wouldn't be able to issue any other remote packet until
5565 these other threads stop. */
5566 if (had_step_over_info && !step_over_info_valid_p ())
5568 struct thread_info *pending;
5570 /* If we only have threads with pending statuses, the restart
5571 below won't restart any thread and so nothing re-inserts the
5572 breakpoint we just stepped over. But we need it inserted
5573 when we later process the pending events, otherwise if
5574 another thread has a pending event for this breakpoint too,
5575 we'd discard its event (because the breakpoint that
5576 originally caused the event was no longer inserted). */
5577 context_switch (ecs->ptid);
5578 insert_breakpoints ();
5580 restart_threads (ecs->event_thread);
5582 /* If we have events pending, go through handle_inferior_event
5583 again, picking up a pending event at random. This avoids
5584 thread starvation. */
5586 /* But not if we just stepped over a watchpoint in order to let
5587 the instruction execute so we can evaluate its expression.
5588 The set of watchpoints that triggered is recorded in the
5589 breakpoint objects themselves (see bp->watchpoint_triggered).
5590 If we processed another event first, that other event could
5591 clobber this info. */
5592 if (ecs->event_thread->stepping_over_watchpoint)
5595 pending = iterate_over_threads (resumed_thread_with_pending_status,
5597 if (pending != NULL)
5599 struct thread_info *tp = ecs->event_thread;
5600 struct regcache *regcache;
5604 fprintf_unfiltered (gdb_stdlog,
5605 "infrun: found resumed threads with "
5606 "pending events, saving status\n");
5609 gdb_assert (pending != tp);
5611 /* Record the event thread's event for later. */
5612 save_waitstatus (tp, &ecs->ws);
5613 /* This was cleared early, by handle_inferior_event. Set it
5614 so this pending event is considered by
5618 gdb_assert (!tp->executing);
5620 regcache = get_thread_regcache (tp->ptid);
5621 tp->suspend.stop_pc = regcache_read_pc (regcache);
5625 fprintf_unfiltered (gdb_stdlog,
5626 "infrun: saved stop_pc=%s for %s "
5627 "(currently_stepping=%d)\n",
5628 paddress (target_gdbarch (),
5629 tp->suspend.stop_pc),
5630 target_pid_to_str (tp->ptid),
5631 currently_stepping (tp));
5634 /* This in-line step-over finished; clear this so we won't
5635 start a new one. This is what handle_signal_stop would
5636 do, if we returned false. */
5637 tp->stepping_over_breakpoint = 0;
5639 /* Wake up the event loop again. */
5640 mark_async_event_handler (infrun_async_inferior_event_token);
5642 prepare_to_wait (ecs);
5650 /* Come here when the program has stopped with a signal. */
5653 handle_signal_stop (struct execution_control_state *ecs)
5655 struct frame_info *frame;
5656 struct gdbarch *gdbarch;
5657 int stopped_by_watchpoint;
5658 enum stop_kind stop_soon;
5661 gdb_assert (ecs->ws.kind == TARGET_WAITKIND_STOPPED);
5663 /* Do we need to clean up the state of a thread that has
5664 completed a displaced single-step? (Doing so usually affects
5665 the PC, so do it here, before we set stop_pc.) */
5666 if (finish_step_over (ecs))
5669 /* If we either finished a single-step or hit a breakpoint, but
5670 the user wanted this thread to be stopped, pretend we got a
5671 SIG0 (generic unsignaled stop). */
5672 if (ecs->event_thread->stop_requested
5673 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
5674 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5676 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5680 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5681 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5682 struct cleanup *old_chain = save_inferior_ptid ();
5684 inferior_ptid = ecs->ptid;
5686 fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = %s\n",
5687 paddress (gdbarch, stop_pc));
5688 if (target_stopped_by_watchpoint ())
5692 fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n");
5694 if (target_stopped_data_address (¤t_target, &addr))
5695 fprintf_unfiltered (gdb_stdlog,
5696 "infrun: stopped data address = %s\n",
5697 paddress (gdbarch, addr));
5699 fprintf_unfiltered (gdb_stdlog,
5700 "infrun: (no data address available)\n");
5703 do_cleanups (old_chain);
5706 /* This is originated from start_remote(), start_inferior() and
5707 shared libraries hook functions. */
5708 stop_soon = get_inferior_stop_soon (ecs->ptid);
5709 if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE)
5711 if (!ptid_equal (ecs->ptid, inferior_ptid))
5712 context_switch (ecs->ptid);
5714 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
5715 stop_print_frame = 1;
5720 /* This originates from attach_command(). We need to overwrite
5721 the stop_signal here, because some kernels don't ignore a
5722 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5723 See more comments in inferior.h. On the other hand, if we
5724 get a non-SIGSTOP, report it to the user - assume the backend
5725 will handle the SIGSTOP if it should show up later.
5727 Also consider that the attach is complete when we see a
5728 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5729 target extended-remote report it instead of a SIGSTOP
5730 (e.g. gdbserver). We already rely on SIGTRAP being our
5731 signal, so this is no exception.
5733 Also consider that the attach is complete when we see a
5734 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5735 the target to stop all threads of the inferior, in case the
5736 low level attach operation doesn't stop them implicitly. If
5737 they weren't stopped implicitly, then the stub will report a
5738 GDB_SIGNAL_0, meaning: stopped for no particular reason
5739 other than GDB's request. */
5740 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
5741 && (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_STOP
5742 || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5743 || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_0))
5745 stop_print_frame = 1;
5747 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5751 /* See if something interesting happened to the non-current thread. If
5752 so, then switch to that thread. */
5753 if (!ptid_equal (ecs->ptid, inferior_ptid))
5756 fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n");
5758 context_switch (ecs->ptid);
5760 if (deprecated_context_hook)
5761 deprecated_context_hook (ptid_to_global_thread_id (ecs->ptid));
5764 /* At this point, get hold of the now-current thread's frame. */
5765 frame = get_current_frame ();
5766 gdbarch = get_frame_arch (frame);
5768 /* Pull the single step breakpoints out of the target. */
5769 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
5771 struct regcache *regcache;
5772 struct address_space *aspace;
5775 regcache = get_thread_regcache (ecs->ptid);
5776 aspace = get_regcache_aspace (regcache);
5777 pc = regcache_read_pc (regcache);
5779 /* However, before doing so, if this single-step breakpoint was
5780 actually for another thread, set this thread up for moving
5782 if (!thread_has_single_step_breakpoint_here (ecs->event_thread,
5785 if (single_step_breakpoint_inserted_here_p (aspace, pc))
5789 fprintf_unfiltered (gdb_stdlog,
5790 "infrun: [%s] hit another thread's "
5791 "single-step breakpoint\n",
5792 target_pid_to_str (ecs->ptid));
5794 ecs->hit_singlestep_breakpoint = 1;
5801 fprintf_unfiltered (gdb_stdlog,
5802 "infrun: [%s] hit its "
5803 "single-step breakpoint\n",
5804 target_pid_to_str (ecs->ptid));
5808 delete_just_stopped_threads_single_step_breakpoints ();
5810 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5811 && ecs->event_thread->control.trap_expected
5812 && ecs->event_thread->stepping_over_watchpoint)
5813 stopped_by_watchpoint = 0;
5815 stopped_by_watchpoint = watchpoints_triggered (&ecs->ws);
5817 /* If necessary, step over this watchpoint. We'll be back to display
5819 if (stopped_by_watchpoint
5820 && (target_have_steppable_watchpoint
5821 || gdbarch_have_nonsteppable_watchpoint (gdbarch)))
5823 /* At this point, we are stopped at an instruction which has
5824 attempted to write to a piece of memory under control of
5825 a watchpoint. The instruction hasn't actually executed
5826 yet. If we were to evaluate the watchpoint expression
5827 now, we would get the old value, and therefore no change
5828 would seem to have occurred.
5830 In order to make watchpoints work `right', we really need
5831 to complete the memory write, and then evaluate the
5832 watchpoint expression. We do this by single-stepping the
5835 It may not be necessary to disable the watchpoint to step over
5836 it. For example, the PA can (with some kernel cooperation)
5837 single step over a watchpoint without disabling the watchpoint.
5839 It is far more common to need to disable a watchpoint to step
5840 the inferior over it. If we have non-steppable watchpoints,
5841 we must disable the current watchpoint; it's simplest to
5842 disable all watchpoints.
5844 Any breakpoint at PC must also be stepped over -- if there's
5845 one, it will have already triggered before the watchpoint
5846 triggered, and we either already reported it to the user, or
5847 it didn't cause a stop and we called keep_going. In either
5848 case, if there was a breakpoint at PC, we must be trying to
5850 ecs->event_thread->stepping_over_watchpoint = 1;
5855 ecs->event_thread->stepping_over_breakpoint = 0;
5856 ecs->event_thread->stepping_over_watchpoint = 0;
5857 bpstat_clear (&ecs->event_thread->control.stop_bpstat);
5858 ecs->event_thread->control.stop_step = 0;
5859 stop_print_frame = 1;
5860 stopped_by_random_signal = 0;
5862 /* Hide inlined functions starting here, unless we just performed stepi or
5863 nexti. After stepi and nexti, always show the innermost frame (not any
5864 inline function call sites). */
5865 if (ecs->event_thread->control.step_range_end != 1)
5867 struct address_space *aspace =
5868 get_regcache_aspace (get_thread_regcache (ecs->ptid));
5870 /* skip_inline_frames is expensive, so we avoid it if we can
5871 determine that the address is one where functions cannot have
5872 been inlined. This improves performance with inferiors that
5873 load a lot of shared libraries, because the solib event
5874 breakpoint is defined as the address of a function (i.e. not
5875 inline). Note that we have to check the previous PC as well
5876 as the current one to catch cases when we have just
5877 single-stepped off a breakpoint prior to reinstating it.
5878 Note that we're assuming that the code we single-step to is
5879 not inline, but that's not definitive: there's nothing
5880 preventing the event breakpoint function from containing
5881 inlined code, and the single-step ending up there. If the
5882 user had set a breakpoint on that inlined code, the missing
5883 skip_inline_frames call would break things. Fortunately
5884 that's an extremely unlikely scenario. */
5885 if (!pc_at_non_inline_function (aspace, stop_pc, &ecs->ws)
5886 && !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5887 && ecs->event_thread->control.trap_expected
5888 && pc_at_non_inline_function (aspace,
5889 ecs->event_thread->prev_pc,
5892 skip_inline_frames (ecs->ptid);
5894 /* Re-fetch current thread's frame in case that invalidated
5896 frame = get_current_frame ();
5897 gdbarch = get_frame_arch (frame);
5901 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5902 && ecs->event_thread->control.trap_expected
5903 && gdbarch_single_step_through_delay_p (gdbarch)
5904 && currently_stepping (ecs->event_thread))
5906 /* We're trying to step off a breakpoint. Turns out that we're
5907 also on an instruction that needs to be stepped multiple
5908 times before it's been fully executing. E.g., architectures
5909 with a delay slot. It needs to be stepped twice, once for
5910 the instruction and once for the delay slot. */
5911 int step_through_delay
5912 = gdbarch_single_step_through_delay (gdbarch, frame);
5914 if (debug_infrun && step_through_delay)
5915 fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n");
5916 if (ecs->event_thread->control.step_range_end == 0
5917 && step_through_delay)
5919 /* The user issued a continue when stopped at a breakpoint.
5920 Set up for another trap and get out of here. */
5921 ecs->event_thread->stepping_over_breakpoint = 1;
5925 else if (step_through_delay)
5927 /* The user issued a step when stopped at a breakpoint.
5928 Maybe we should stop, maybe we should not - the delay
5929 slot *might* correspond to a line of source. In any
5930 case, don't decide that here, just set
5931 ecs->stepping_over_breakpoint, making sure we
5932 single-step again before breakpoints are re-inserted. */
5933 ecs->event_thread->stepping_over_breakpoint = 1;
5937 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5938 handles this event. */
5939 ecs->event_thread->control.stop_bpstat
5940 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5941 stop_pc, ecs->ptid, &ecs->ws);
5943 /* Following in case break condition called a
5945 stop_print_frame = 1;
5947 /* This is where we handle "moribund" watchpoints. Unlike
5948 software breakpoints traps, hardware watchpoint traps are
5949 always distinguishable from random traps. If no high-level
5950 watchpoint is associated with the reported stop data address
5951 anymore, then the bpstat does not explain the signal ---
5952 simply make sure to ignore it if `stopped_by_watchpoint' is
5956 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5957 && !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
5959 && stopped_by_watchpoint)
5960 fprintf_unfiltered (gdb_stdlog,
5961 "infrun: no user watchpoint explains "
5962 "watchpoint SIGTRAP, ignoring\n");
5964 /* NOTE: cagney/2003-03-29: These checks for a random signal
5965 at one stage in the past included checks for an inferior
5966 function call's call dummy's return breakpoint. The original
5967 comment, that went with the test, read:
5969 ``End of a stack dummy. Some systems (e.g. Sony news) give
5970 another signal besides SIGTRAP, so check here as well as
5973 If someone ever tries to get call dummys on a
5974 non-executable stack to work (where the target would stop
5975 with something like a SIGSEGV), then those tests might need
5976 to be re-instated. Given, however, that the tests were only
5977 enabled when momentary breakpoints were not being used, I
5978 suspect that it won't be the case.
5980 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5981 be necessary for call dummies on a non-executable stack on
5984 /* See if the breakpoints module can explain the signal. */
5986 = !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
5987 ecs->event_thread->suspend.stop_signal);
5989 /* Maybe this was a trap for a software breakpoint that has since
5991 if (random_signal && target_stopped_by_sw_breakpoint ())
5993 if (program_breakpoint_here_p (gdbarch, stop_pc))
5995 struct regcache *regcache;
5998 /* Re-adjust PC to what the program would see if GDB was not
6000 regcache = get_thread_regcache (ecs->event_thread->ptid);
6001 decr_pc = gdbarch_decr_pc_after_break (gdbarch);
6004 struct cleanup *old_cleanups = make_cleanup (null_cleanup, NULL);
6006 if (record_full_is_used ())
6007 record_full_gdb_operation_disable_set ();
6009 regcache_write_pc (regcache, stop_pc + decr_pc);
6011 do_cleanups (old_cleanups);
6016 /* A delayed software breakpoint event. Ignore the trap. */
6018 fprintf_unfiltered (gdb_stdlog,
6019 "infrun: delayed software breakpoint "
6020 "trap, ignoring\n");
6025 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6026 has since been removed. */
6027 if (random_signal && target_stopped_by_hw_breakpoint ())
6029 /* A delayed hardware breakpoint event. Ignore the trap. */
6031 fprintf_unfiltered (gdb_stdlog,
6032 "infrun: delayed hardware breakpoint/watchpoint "
6033 "trap, ignoring\n");
6037 /* If not, perhaps stepping/nexting can. */
6039 random_signal = !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
6040 && currently_stepping (ecs->event_thread));
6042 /* Perhaps the thread hit a single-step breakpoint of _another_
6043 thread. Single-step breakpoints are transparent to the
6044 breakpoints module. */
6046 random_signal = !ecs->hit_singlestep_breakpoint;
6048 /* No? Perhaps we got a moribund watchpoint. */
6050 random_signal = !stopped_by_watchpoint;
6052 /* For the program's own signals, act according to
6053 the signal handling tables. */
6057 /* Signal not for debugging purposes. */
6058 struct inferior *inf = find_inferior_ptid (ecs->ptid);
6059 enum gdb_signal stop_signal = ecs->event_thread->suspend.stop_signal;
6062 fprintf_unfiltered (gdb_stdlog, "infrun: random signal (%s)\n",
6063 gdb_signal_to_symbol_string (stop_signal));
6065 stopped_by_random_signal = 1;
6067 /* Always stop on signals if we're either just gaining control
6068 of the program, or the user explicitly requested this thread
6069 to remain stopped. */
6070 if (stop_soon != NO_STOP_QUIETLY
6071 || ecs->event_thread->stop_requested
6073 && signal_stop_state (ecs->event_thread->suspend.stop_signal)))
6079 /* Notify observers the signal has "handle print" set. Note we
6080 returned early above if stopping; normal_stop handles the
6081 printing in that case. */
6082 if (signal_print[ecs->event_thread->suspend.stop_signal])
6084 /* The signal table tells us to print about this signal. */
6085 target_terminal_ours_for_output ();
6086 observer_notify_signal_received (ecs->event_thread->suspend.stop_signal);
6087 target_terminal_inferior ();
6090 /* Clear the signal if it should not be passed. */
6091 if (signal_program[ecs->event_thread->suspend.stop_signal] == 0)
6092 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
6094 if (ecs->event_thread->prev_pc == stop_pc
6095 && ecs->event_thread->control.trap_expected
6096 && ecs->event_thread->control.step_resume_breakpoint == NULL)
6100 /* We were just starting a new sequence, attempting to
6101 single-step off of a breakpoint and expecting a SIGTRAP.
6102 Instead this signal arrives. This signal will take us out
6103 of the stepping range so GDB needs to remember to, when
6104 the signal handler returns, resume stepping off that
6106 /* To simplify things, "continue" is forced to use the same
6107 code paths as single-step - set a breakpoint at the
6108 signal return address and then, once hit, step off that
6111 fprintf_unfiltered (gdb_stdlog,
6112 "infrun: signal arrived while stepping over "
6115 was_in_line = step_over_info_valid_p ();
6116 clear_step_over_info ();
6117 insert_hp_step_resume_breakpoint_at_frame (frame);
6118 ecs->event_thread->step_after_step_resume_breakpoint = 1;
6119 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6120 ecs->event_thread->control.trap_expected = 0;
6122 if (target_is_non_stop_p ())
6124 /* Either "set non-stop" is "on", or the target is
6125 always in non-stop mode. In this case, we have a bit
6126 more work to do. Resume the current thread, and if
6127 we had paused all threads, restart them while the
6128 signal handler runs. */
6133 restart_threads (ecs->event_thread);
6135 else if (debug_infrun)
6137 fprintf_unfiltered (gdb_stdlog,
6138 "infrun: no need to restart threads\n");
6143 /* If we were nexting/stepping some other thread, switch to
6144 it, so that we don't continue it, losing control. */
6145 if (!switch_back_to_stepped_thread (ecs))
6150 if (ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_0
6151 && (pc_in_thread_step_range (stop_pc, ecs->event_thread)
6152 || ecs->event_thread->control.step_range_end == 1)
6153 && frame_id_eq (get_stack_frame_id (frame),
6154 ecs->event_thread->control.step_stack_frame_id)
6155 && ecs->event_thread->control.step_resume_breakpoint == NULL)
6157 /* The inferior is about to take a signal that will take it
6158 out of the single step range. Set a breakpoint at the
6159 current PC (which is presumably where the signal handler
6160 will eventually return) and then allow the inferior to
6163 Note that this is only needed for a signal delivered
6164 while in the single-step range. Nested signals aren't a
6165 problem as they eventually all return. */
6167 fprintf_unfiltered (gdb_stdlog,
6168 "infrun: signal may take us out of "
6169 "single-step range\n");
6171 clear_step_over_info ();
6172 insert_hp_step_resume_breakpoint_at_frame (frame);
6173 ecs->event_thread->step_after_step_resume_breakpoint = 1;
6174 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6175 ecs->event_thread->control.trap_expected = 0;
6180 /* Note: step_resume_breakpoint may be non-NULL. This occures
6181 when either there's a nested signal, or when there's a
6182 pending signal enabled just as the signal handler returns
6183 (leaving the inferior at the step-resume-breakpoint without
6184 actually executing it). Either way continue until the
6185 breakpoint is really hit. */
6187 if (!switch_back_to_stepped_thread (ecs))
6190 fprintf_unfiltered (gdb_stdlog,
6191 "infrun: random signal, keep going\n");
6198 process_event_stop_test (ecs);
6201 /* Come here when we've got some debug event / signal we can explain
6202 (IOW, not a random signal), and test whether it should cause a
6203 stop, or whether we should resume the inferior (transparently).
6204 E.g., could be a breakpoint whose condition evaluates false; we
6205 could be still stepping within the line; etc. */
6208 process_event_stop_test (struct execution_control_state *ecs)
6210 struct symtab_and_line stop_pc_sal;
6211 struct frame_info *frame;
6212 struct gdbarch *gdbarch;
6213 CORE_ADDR jmp_buf_pc;
6214 struct bpstat_what what;
6216 /* Handle cases caused by hitting a breakpoint. */
6218 frame = get_current_frame ();
6219 gdbarch = get_frame_arch (frame);
6221 what = bpstat_what (ecs->event_thread->control.stop_bpstat);
6223 if (what.call_dummy)
6225 stop_stack_dummy = what.call_dummy;
6228 /* A few breakpoint types have callbacks associated (e.g.,
6229 bp_jit_event). Run them now. */
6230 bpstat_run_callbacks (ecs->event_thread->control.stop_bpstat);
6232 /* If we hit an internal event that triggers symbol changes, the
6233 current frame will be invalidated within bpstat_what (e.g., if we
6234 hit an internal solib event). Re-fetch it. */
6235 frame = get_current_frame ();
6236 gdbarch = get_frame_arch (frame);
6238 switch (what.main_action)
6240 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
6241 /* If we hit the breakpoint at longjmp while stepping, we
6242 install a momentary breakpoint at the target of the
6246 fprintf_unfiltered (gdb_stdlog,
6247 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6249 ecs->event_thread->stepping_over_breakpoint = 1;
6251 if (what.is_longjmp)
6253 struct value *arg_value;
6255 /* If we set the longjmp breakpoint via a SystemTap probe,
6256 then use it to extract the arguments. The destination PC
6257 is the third argument to the probe. */
6258 arg_value = probe_safe_evaluate_at_pc (frame, 2);
6261 jmp_buf_pc = value_as_address (arg_value);
6262 jmp_buf_pc = gdbarch_addr_bits_remove (gdbarch, jmp_buf_pc);
6264 else if (!gdbarch_get_longjmp_target_p (gdbarch)
6265 || !gdbarch_get_longjmp_target (gdbarch,
6266 frame, &jmp_buf_pc))
6269 fprintf_unfiltered (gdb_stdlog,
6270 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6271 "(!gdbarch_get_longjmp_target)\n");
6276 /* Insert a breakpoint at resume address. */
6277 insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc);
6280 check_exception_resume (ecs, frame);
6284 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
6286 struct frame_info *init_frame;
6288 /* There are several cases to consider.
6290 1. The initiating frame no longer exists. In this case we
6291 must stop, because the exception or longjmp has gone too
6294 2. The initiating frame exists, and is the same as the
6295 current frame. We stop, because the exception or longjmp
6298 3. The initiating frame exists and is different from the
6299 current frame. This means the exception or longjmp has
6300 been caught beneath the initiating frame, so keep going.
6302 4. longjmp breakpoint has been placed just to protect
6303 against stale dummy frames and user is not interested in
6304 stopping around longjmps. */
6307 fprintf_unfiltered (gdb_stdlog,
6308 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6310 gdb_assert (ecs->event_thread->control.exception_resume_breakpoint
6312 delete_exception_resume_breakpoint (ecs->event_thread);
6314 if (what.is_longjmp)
6316 check_longjmp_breakpoint_for_call_dummy (ecs->event_thread);
6318 if (!frame_id_p (ecs->event_thread->initiating_frame))
6326 init_frame = frame_find_by_id (ecs->event_thread->initiating_frame);
6330 struct frame_id current_id
6331 = get_frame_id (get_current_frame ());
6332 if (frame_id_eq (current_id,
6333 ecs->event_thread->initiating_frame))
6335 /* Case 2. Fall through. */
6345 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6347 delete_step_resume_breakpoint (ecs->event_thread);
6349 end_stepping_range (ecs);
6353 case BPSTAT_WHAT_SINGLE:
6355 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
6356 ecs->event_thread->stepping_over_breakpoint = 1;
6357 /* Still need to check other stuff, at least the case where we
6358 are stepping and step out of the right range. */
6361 case BPSTAT_WHAT_STEP_RESUME:
6363 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6365 delete_step_resume_breakpoint (ecs->event_thread);
6366 if (ecs->event_thread->control.proceed_to_finish
6367 && execution_direction == EXEC_REVERSE)
6369 struct thread_info *tp = ecs->event_thread;
6371 /* We are finishing a function in reverse, and just hit the
6372 step-resume breakpoint at the start address of the
6373 function, and we're almost there -- just need to back up
6374 by one more single-step, which should take us back to the
6376 tp->control.step_range_start = tp->control.step_range_end = 1;
6380 fill_in_stop_func (gdbarch, ecs);
6381 if (stop_pc == ecs->stop_func_start
6382 && execution_direction == EXEC_REVERSE)
6384 /* We are stepping over a function call in reverse, and just
6385 hit the step-resume breakpoint at the start address of
6386 the function. Go back to single-stepping, which should
6387 take us back to the function call. */
6388 ecs->event_thread->stepping_over_breakpoint = 1;
6394 case BPSTAT_WHAT_STOP_NOISY:
6396 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6397 stop_print_frame = 1;
6399 /* Assume the thread stopped for a breapoint. We'll still check
6400 whether a/the breakpoint is there when the thread is next
6402 ecs->event_thread->stepping_over_breakpoint = 1;
6407 case BPSTAT_WHAT_STOP_SILENT:
6409 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6410 stop_print_frame = 0;
6412 /* Assume the thread stopped for a breapoint. We'll still check
6413 whether a/the breakpoint is there when the thread is next
6415 ecs->event_thread->stepping_over_breakpoint = 1;
6419 case BPSTAT_WHAT_HP_STEP_RESUME:
6421 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6423 delete_step_resume_breakpoint (ecs->event_thread);
6424 if (ecs->event_thread->step_after_step_resume_breakpoint)
6426 /* Back when the step-resume breakpoint was inserted, we
6427 were trying to single-step off a breakpoint. Go back to
6429 ecs->event_thread->step_after_step_resume_breakpoint = 0;
6430 ecs->event_thread->stepping_over_breakpoint = 1;
6436 case BPSTAT_WHAT_KEEP_CHECKING:
6440 /* If we stepped a permanent breakpoint and we had a high priority
6441 step-resume breakpoint for the address we stepped, but we didn't
6442 hit it, then we must have stepped into the signal handler. The
6443 step-resume was only necessary to catch the case of _not_
6444 stepping into the handler, so delete it, and fall through to
6445 checking whether the step finished. */
6446 if (ecs->event_thread->stepped_breakpoint)
6448 struct breakpoint *sr_bp
6449 = ecs->event_thread->control.step_resume_breakpoint;
6452 && sr_bp->loc->permanent
6453 && sr_bp->type == bp_hp_step_resume
6454 && sr_bp->loc->address == ecs->event_thread->prev_pc)
6457 fprintf_unfiltered (gdb_stdlog,
6458 "infrun: stepped permanent breakpoint, stopped in "
6460 delete_step_resume_breakpoint (ecs->event_thread);
6461 ecs->event_thread->step_after_step_resume_breakpoint = 0;
6465 /* We come here if we hit a breakpoint but should not stop for it.
6466 Possibly we also were stepping and should stop for that. So fall
6467 through and test for stepping. But, if not stepping, do not
6470 /* In all-stop mode, if we're currently stepping but have stopped in
6471 some other thread, we need to switch back to the stepped thread. */
6472 if (switch_back_to_stepped_thread (ecs))
6475 if (ecs->event_thread->control.step_resume_breakpoint)
6478 fprintf_unfiltered (gdb_stdlog,
6479 "infrun: step-resume breakpoint is inserted\n");
6481 /* Having a step-resume breakpoint overrides anything
6482 else having to do with stepping commands until
6483 that breakpoint is reached. */
6488 if (ecs->event_thread->control.step_range_end == 0)
6491 fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n");
6492 /* Likewise if we aren't even stepping. */
6497 /* Re-fetch current thread's frame in case the code above caused
6498 the frame cache to be re-initialized, making our FRAME variable
6499 a dangling pointer. */
6500 frame = get_current_frame ();
6501 gdbarch = get_frame_arch (frame);
6502 fill_in_stop_func (gdbarch, ecs);
6504 /* If stepping through a line, keep going if still within it.
6506 Note that step_range_end is the address of the first instruction
6507 beyond the step range, and NOT the address of the last instruction
6510 Note also that during reverse execution, we may be stepping
6511 through a function epilogue and therefore must detect when
6512 the current-frame changes in the middle of a line. */
6514 if (pc_in_thread_step_range (stop_pc, ecs->event_thread)
6515 && (execution_direction != EXEC_REVERSE
6516 || frame_id_eq (get_frame_id (frame),
6517 ecs->event_thread->control.step_frame_id)))
6521 (gdb_stdlog, "infrun: stepping inside range [%s-%s]\n",
6522 paddress (gdbarch, ecs->event_thread->control.step_range_start),
6523 paddress (gdbarch, ecs->event_thread->control.step_range_end));
6525 /* Tentatively re-enable range stepping; `resume' disables it if
6526 necessary (e.g., if we're stepping over a breakpoint or we
6527 have software watchpoints). */
6528 ecs->event_thread->control.may_range_step = 1;
6530 /* When stepping backward, stop at beginning of line range
6531 (unless it's the function entry point, in which case
6532 keep going back to the call point). */
6533 if (stop_pc == ecs->event_thread->control.step_range_start
6534 && stop_pc != ecs->stop_func_start
6535 && execution_direction == EXEC_REVERSE)
6536 end_stepping_range (ecs);
6543 /* We stepped out of the stepping range. */
6545 /* If we are stepping at the source level and entered the runtime
6546 loader dynamic symbol resolution code...
6548 EXEC_FORWARD: we keep on single stepping until we exit the run
6549 time loader code and reach the callee's address.
6551 EXEC_REVERSE: we've already executed the callee (backward), and
6552 the runtime loader code is handled just like any other
6553 undebuggable function call. Now we need only keep stepping
6554 backward through the trampoline code, and that's handled further
6555 down, so there is nothing for us to do here. */
6557 if (execution_direction != EXEC_REVERSE
6558 && ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6559 && in_solib_dynsym_resolve_code (stop_pc))
6561 CORE_ADDR pc_after_resolver =
6562 gdbarch_skip_solib_resolver (gdbarch, stop_pc);
6565 fprintf_unfiltered (gdb_stdlog,
6566 "infrun: stepped into dynsym resolve code\n");
6568 if (pc_after_resolver)
6570 /* Set up a step-resume breakpoint at the address
6571 indicated by SKIP_SOLIB_RESOLVER. */
6572 struct symtab_and_line sr_sal;
6575 sr_sal.pc = pc_after_resolver;
6576 sr_sal.pspace = get_frame_program_space (frame);
6578 insert_step_resume_breakpoint_at_sal (gdbarch,
6579 sr_sal, null_frame_id);
6586 if (ecs->event_thread->control.step_range_end != 1
6587 && (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6588 || ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
6589 && get_frame_type (frame) == SIGTRAMP_FRAME)
6592 fprintf_unfiltered (gdb_stdlog,
6593 "infrun: stepped into signal trampoline\n");
6594 /* The inferior, while doing a "step" or "next", has ended up in
6595 a signal trampoline (either by a signal being delivered or by
6596 the signal handler returning). Just single-step until the
6597 inferior leaves the trampoline (either by calling the handler
6603 /* If we're in the return path from a shared library trampoline,
6604 we want to proceed through the trampoline when stepping. */
6605 /* macro/2012-04-25: This needs to come before the subroutine
6606 call check below as on some targets return trampolines look
6607 like subroutine calls (MIPS16 return thunks). */
6608 if (gdbarch_in_solib_return_trampoline (gdbarch,
6609 stop_pc, ecs->stop_func_name)
6610 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
6612 /* Determine where this trampoline returns. */
6613 CORE_ADDR real_stop_pc;
6615 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
6618 fprintf_unfiltered (gdb_stdlog,
6619 "infrun: stepped into solib return tramp\n");
6621 /* Only proceed through if we know where it's going. */
6624 /* And put the step-breakpoint there and go until there. */
6625 struct symtab_and_line sr_sal;
6627 init_sal (&sr_sal); /* initialize to zeroes */
6628 sr_sal.pc = real_stop_pc;
6629 sr_sal.section = find_pc_overlay (sr_sal.pc);
6630 sr_sal.pspace = get_frame_program_space (frame);
6632 /* Do not specify what the fp should be when we stop since
6633 on some machines the prologue is where the new fp value
6635 insert_step_resume_breakpoint_at_sal (gdbarch,
6636 sr_sal, null_frame_id);
6638 /* Restart without fiddling with the step ranges or
6645 /* Check for subroutine calls. The check for the current frame
6646 equalling the step ID is not necessary - the check of the
6647 previous frame's ID is sufficient - but it is a common case and
6648 cheaper than checking the previous frame's ID.
6650 NOTE: frame_id_eq will never report two invalid frame IDs as
6651 being equal, so to get into this block, both the current and
6652 previous frame must have valid frame IDs. */
6653 /* The outer_frame_id check is a heuristic to detect stepping
6654 through startup code. If we step over an instruction which
6655 sets the stack pointer from an invalid value to a valid value,
6656 we may detect that as a subroutine call from the mythical
6657 "outermost" function. This could be fixed by marking
6658 outermost frames as !stack_p,code_p,special_p. Then the
6659 initial outermost frame, before sp was valid, would
6660 have code_addr == &_start. See the comment in frame_id_eq
6662 if (!frame_id_eq (get_stack_frame_id (frame),
6663 ecs->event_thread->control.step_stack_frame_id)
6664 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6665 ecs->event_thread->control.step_stack_frame_id)
6666 && (!frame_id_eq (ecs->event_thread->control.step_stack_frame_id,
6668 || (ecs->event_thread->control.step_start_function
6669 != find_pc_function (stop_pc)))))
6671 CORE_ADDR real_stop_pc;
6674 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n");
6676 if (ecs->event_thread->control.step_over_calls == STEP_OVER_NONE)
6678 /* I presume that step_over_calls is only 0 when we're
6679 supposed to be stepping at the assembly language level
6680 ("stepi"). Just stop. */
6681 /* And this works the same backward as frontward. MVS */
6682 end_stepping_range (ecs);
6686 /* Reverse stepping through solib trampolines. */
6688 if (execution_direction == EXEC_REVERSE
6689 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE
6690 && (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
6691 || (ecs->stop_func_start == 0
6692 && in_solib_dynsym_resolve_code (stop_pc))))
6694 /* Any solib trampoline code can be handled in reverse
6695 by simply continuing to single-step. We have already
6696 executed the solib function (backwards), and a few
6697 steps will take us back through the trampoline to the
6703 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
6705 /* We're doing a "next".
6707 Normal (forward) execution: set a breakpoint at the
6708 callee's return address (the address at which the caller
6711 Reverse (backward) execution. set the step-resume
6712 breakpoint at the start of the function that we just
6713 stepped into (backwards), and continue to there. When we
6714 get there, we'll need to single-step back to the caller. */
6716 if (execution_direction == EXEC_REVERSE)
6718 /* If we're already at the start of the function, we've either
6719 just stepped backward into a single instruction function,
6720 or stepped back out of a signal handler to the first instruction
6721 of the function. Just keep going, which will single-step back
6723 if (ecs->stop_func_start != stop_pc && ecs->stop_func_start != 0)
6725 struct symtab_and_line sr_sal;
6727 /* Normal function call return (static or dynamic). */
6729 sr_sal.pc = ecs->stop_func_start;
6730 sr_sal.pspace = get_frame_program_space (frame);
6731 insert_step_resume_breakpoint_at_sal (gdbarch,
6732 sr_sal, null_frame_id);
6736 insert_step_resume_breakpoint_at_caller (frame);
6742 /* If we are in a function call trampoline (a stub between the
6743 calling routine and the real function), locate the real
6744 function. That's what tells us (a) whether we want to step
6745 into it at all, and (b) what prologue we want to run to the
6746 end of, if we do step into it. */
6747 real_stop_pc = skip_language_trampoline (frame, stop_pc);
6748 if (real_stop_pc == 0)
6749 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
6750 if (real_stop_pc != 0)
6751 ecs->stop_func_start = real_stop_pc;
6753 if (real_stop_pc != 0 && in_solib_dynsym_resolve_code (real_stop_pc))
6755 struct symtab_and_line sr_sal;
6758 sr_sal.pc = ecs->stop_func_start;
6759 sr_sal.pspace = get_frame_program_space (frame);
6761 insert_step_resume_breakpoint_at_sal (gdbarch,
6762 sr_sal, null_frame_id);
6767 /* If we have line number information for the function we are
6768 thinking of stepping into and the function isn't on the skip
6771 If there are several symtabs at that PC (e.g. with include
6772 files), just want to know whether *any* of them have line
6773 numbers. find_pc_line handles this. */
6775 struct symtab_and_line tmp_sal;
6777 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
6778 if (tmp_sal.line != 0
6779 && !function_name_is_marked_for_skip (ecs->stop_func_name,
6782 if (execution_direction == EXEC_REVERSE)
6783 handle_step_into_function_backward (gdbarch, ecs);
6785 handle_step_into_function (gdbarch, ecs);
6790 /* If we have no line number and the step-stop-if-no-debug is
6791 set, we stop the step so that the user has a chance to switch
6792 in assembly mode. */
6793 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6794 && step_stop_if_no_debug)
6796 end_stepping_range (ecs);
6800 if (execution_direction == EXEC_REVERSE)
6802 /* If we're already at the start of the function, we've either just
6803 stepped backward into a single instruction function without line
6804 number info, or stepped back out of a signal handler to the first
6805 instruction of the function without line number info. Just keep
6806 going, which will single-step back to the caller. */
6807 if (ecs->stop_func_start != stop_pc)
6809 /* Set a breakpoint at callee's start address.
6810 From there we can step once and be back in the caller. */
6811 struct symtab_and_line sr_sal;
6814 sr_sal.pc = ecs->stop_func_start;
6815 sr_sal.pspace = get_frame_program_space (frame);
6816 insert_step_resume_breakpoint_at_sal (gdbarch,
6817 sr_sal, null_frame_id);
6821 /* Set a breakpoint at callee's return address (the address
6822 at which the caller will resume). */
6823 insert_step_resume_breakpoint_at_caller (frame);
6829 /* Reverse stepping through solib trampolines. */
6831 if (execution_direction == EXEC_REVERSE
6832 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
6834 if (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
6835 || (ecs->stop_func_start == 0
6836 && in_solib_dynsym_resolve_code (stop_pc)))
6838 /* Any solib trampoline code can be handled in reverse
6839 by simply continuing to single-step. We have already
6840 executed the solib function (backwards), and a few
6841 steps will take us back through the trampoline to the
6846 else if (in_solib_dynsym_resolve_code (stop_pc))
6848 /* Stepped backward into the solib dynsym resolver.
6849 Set a breakpoint at its start and continue, then
6850 one more step will take us out. */
6851 struct symtab_and_line sr_sal;
6854 sr_sal.pc = ecs->stop_func_start;
6855 sr_sal.pspace = get_frame_program_space (frame);
6856 insert_step_resume_breakpoint_at_sal (gdbarch,
6857 sr_sal, null_frame_id);
6863 stop_pc_sal = find_pc_line (stop_pc, 0);
6865 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6866 the trampoline processing logic, however, there are some trampolines
6867 that have no names, so we should do trampoline handling first. */
6868 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6869 && ecs->stop_func_name == NULL
6870 && stop_pc_sal.line == 0)
6873 fprintf_unfiltered (gdb_stdlog,
6874 "infrun: stepped into undebuggable function\n");
6876 /* The inferior just stepped into, or returned to, an
6877 undebuggable function (where there is no debugging information
6878 and no line number corresponding to the address where the
6879 inferior stopped). Since we want to skip this kind of code,
6880 we keep going until the inferior returns from this
6881 function - unless the user has asked us not to (via
6882 set step-mode) or we no longer know how to get back
6883 to the call site. */
6884 if (step_stop_if_no_debug
6885 || !frame_id_p (frame_unwind_caller_id (frame)))
6887 /* If we have no line number and the step-stop-if-no-debug
6888 is set, we stop the step so that the user has a chance to
6889 switch in assembly mode. */
6890 end_stepping_range (ecs);
6895 /* Set a breakpoint at callee's return address (the address
6896 at which the caller will resume). */
6897 insert_step_resume_breakpoint_at_caller (frame);
6903 if (ecs->event_thread->control.step_range_end == 1)
6905 /* It is stepi or nexti. We always want to stop stepping after
6908 fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
6909 end_stepping_range (ecs);
6913 if (stop_pc_sal.line == 0)
6915 /* We have no line number information. That means to stop
6916 stepping (does this always happen right after one instruction,
6917 when we do "s" in a function with no line numbers,
6918 or can this happen as a result of a return or longjmp?). */
6920 fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n");
6921 end_stepping_range (ecs);
6925 /* Look for "calls" to inlined functions, part one. If the inline
6926 frame machinery detected some skipped call sites, we have entered
6927 a new inline function. */
6929 if (frame_id_eq (get_frame_id (get_current_frame ()),
6930 ecs->event_thread->control.step_frame_id)
6931 && inline_skipped_frames (ecs->ptid))
6933 struct symtab_and_line call_sal;
6936 fprintf_unfiltered (gdb_stdlog,
6937 "infrun: stepped into inlined function\n");
6939 find_frame_sal (get_current_frame (), &call_sal);
6941 if (ecs->event_thread->control.step_over_calls != STEP_OVER_ALL)
6943 /* For "step", we're going to stop. But if the call site
6944 for this inlined function is on the same source line as
6945 we were previously stepping, go down into the function
6946 first. Otherwise stop at the call site. */
6948 if (call_sal.line == ecs->event_thread->current_line
6949 && call_sal.symtab == ecs->event_thread->current_symtab)
6950 step_into_inline_frame (ecs->ptid);
6952 end_stepping_range (ecs);
6957 /* For "next", we should stop at the call site if it is on a
6958 different source line. Otherwise continue through the
6959 inlined function. */
6960 if (call_sal.line == ecs->event_thread->current_line
6961 && call_sal.symtab == ecs->event_thread->current_symtab)
6964 end_stepping_range (ecs);
6969 /* Look for "calls" to inlined functions, part two. If we are still
6970 in the same real function we were stepping through, but we have
6971 to go further up to find the exact frame ID, we are stepping
6972 through a more inlined call beyond its call site. */
6974 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6975 && !frame_id_eq (get_frame_id (get_current_frame ()),
6976 ecs->event_thread->control.step_frame_id)
6977 && stepped_in_from (get_current_frame (),
6978 ecs->event_thread->control.step_frame_id))
6981 fprintf_unfiltered (gdb_stdlog,
6982 "infrun: stepping through inlined function\n");
6984 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
6987 end_stepping_range (ecs);
6991 if ((stop_pc == stop_pc_sal.pc)
6992 && (ecs->event_thread->current_line != stop_pc_sal.line
6993 || ecs->event_thread->current_symtab != stop_pc_sal.symtab))
6995 /* We are at the start of a different line. So stop. Note that
6996 we don't stop if we step into the middle of a different line.
6997 That is said to make things like for (;;) statements work
7000 fprintf_unfiltered (gdb_stdlog,
7001 "infrun: stepped to a different line\n");
7002 end_stepping_range (ecs);
7006 /* We aren't done stepping.
7008 Optimize by setting the stepping range to the line.
7009 (We might not be in the original line, but if we entered a
7010 new line in mid-statement, we continue stepping. This makes
7011 things like for(;;) statements work better.) */
7013 ecs->event_thread->control.step_range_start = stop_pc_sal.pc;
7014 ecs->event_thread->control.step_range_end = stop_pc_sal.end;
7015 ecs->event_thread->control.may_range_step = 1;
7016 set_step_info (frame, stop_pc_sal);
7019 fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n");
7023 /* In all-stop mode, if we're currently stepping but have stopped in
7024 some other thread, we may need to switch back to the stepped
7025 thread. Returns true we set the inferior running, false if we left
7026 it stopped (and the event needs further processing). */
7029 switch_back_to_stepped_thread (struct execution_control_state *ecs)
7031 if (!target_is_non_stop_p ())
7033 struct thread_info *tp;
7034 struct thread_info *stepping_thread;
7036 /* If any thread is blocked on some internal breakpoint, and we
7037 simply need to step over that breakpoint to get it going
7038 again, do that first. */
7040 /* However, if we see an event for the stepping thread, then we
7041 know all other threads have been moved past their breakpoints
7042 already. Let the caller check whether the step is finished,
7043 etc., before deciding to move it past a breakpoint. */
7044 if (ecs->event_thread->control.step_range_end != 0)
7047 /* Check if the current thread is blocked on an incomplete
7048 step-over, interrupted by a random signal. */
7049 if (ecs->event_thread->control.trap_expected
7050 && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_TRAP)
7054 fprintf_unfiltered (gdb_stdlog,
7055 "infrun: need to finish step-over of [%s]\n",
7056 target_pid_to_str (ecs->event_thread->ptid));
7062 /* Check if the current thread is blocked by a single-step
7063 breakpoint of another thread. */
7064 if (ecs->hit_singlestep_breakpoint)
7068 fprintf_unfiltered (gdb_stdlog,
7069 "infrun: need to step [%s] over single-step "
7071 target_pid_to_str (ecs->ptid));
7077 /* If this thread needs yet another step-over (e.g., stepping
7078 through a delay slot), do it first before moving on to
7080 if (thread_still_needs_step_over (ecs->event_thread))
7084 fprintf_unfiltered (gdb_stdlog,
7085 "infrun: thread [%s] still needs step-over\n",
7086 target_pid_to_str (ecs->event_thread->ptid));
7092 /* If scheduler locking applies even if not stepping, there's no
7093 need to walk over threads. Above we've checked whether the
7094 current thread is stepping. If some other thread not the
7095 event thread is stepping, then it must be that scheduler
7096 locking is not in effect. */
7097 if (schedlock_applies (ecs->event_thread))
7100 /* Otherwise, we no longer expect a trap in the current thread.
7101 Clear the trap_expected flag before switching back -- this is
7102 what keep_going does as well, if we call it. */
7103 ecs->event_thread->control.trap_expected = 0;
7105 /* Likewise, clear the signal if it should not be passed. */
7106 if (!signal_program[ecs->event_thread->suspend.stop_signal])
7107 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
7109 /* Do all pending step-overs before actually proceeding with
7111 if (start_step_over ())
7113 prepare_to_wait (ecs);
7117 /* Look for the stepping/nexting thread. */
7118 stepping_thread = NULL;
7120 ALL_NON_EXITED_THREADS (tp)
7122 /* Ignore threads of processes the caller is not
7125 && ptid_get_pid (tp->ptid) != ptid_get_pid (ecs->ptid))
7128 /* When stepping over a breakpoint, we lock all threads
7129 except the one that needs to move past the breakpoint.
7130 If a non-event thread has this set, the "incomplete
7131 step-over" check above should have caught it earlier. */
7132 if (tp->control.trap_expected)
7134 internal_error (__FILE__, __LINE__,
7135 "[%s] has inconsistent state: "
7136 "trap_expected=%d\n",
7137 target_pid_to_str (tp->ptid),
7138 tp->control.trap_expected);
7141 /* Did we find the stepping thread? */
7142 if (tp->control.step_range_end)
7144 /* Yep. There should only one though. */
7145 gdb_assert (stepping_thread == NULL);
7147 /* The event thread is handled at the top, before we
7149 gdb_assert (tp != ecs->event_thread);
7151 /* If some thread other than the event thread is
7152 stepping, then scheduler locking can't be in effect,
7153 otherwise we wouldn't have resumed the current event
7154 thread in the first place. */
7155 gdb_assert (!schedlock_applies (tp));
7157 stepping_thread = tp;
7161 if (stepping_thread != NULL)
7164 fprintf_unfiltered (gdb_stdlog,
7165 "infrun: switching back to stepped thread\n");
7167 if (keep_going_stepped_thread (stepping_thread))
7169 prepare_to_wait (ecs);
7178 /* Set a previously stepped thread back to stepping. Returns true on
7179 success, false if the resume is not possible (e.g., the thread
7183 keep_going_stepped_thread (struct thread_info *tp)
7185 struct frame_info *frame;
7186 struct execution_control_state ecss;
7187 struct execution_control_state *ecs = &ecss;
7189 /* If the stepping thread exited, then don't try to switch back and
7190 resume it, which could fail in several different ways depending
7191 on the target. Instead, just keep going.
7193 We can find a stepping dead thread in the thread list in two
7196 - The target supports thread exit events, and when the target
7197 tries to delete the thread from the thread list, inferior_ptid
7198 pointed at the exiting thread. In such case, calling
7199 delete_thread does not really remove the thread from the list;
7200 instead, the thread is left listed, with 'exited' state.
7202 - The target's debug interface does not support thread exit
7203 events, and so we have no idea whatsoever if the previously
7204 stepping thread is still alive. For that reason, we need to
7205 synchronously query the target now. */
7207 if (is_exited (tp->ptid)
7208 || !target_thread_alive (tp->ptid))
7211 fprintf_unfiltered (gdb_stdlog,
7212 "infrun: not resuming previously "
7213 "stepped thread, it has vanished\n");
7215 delete_thread (tp->ptid);
7220 fprintf_unfiltered (gdb_stdlog,
7221 "infrun: resuming previously stepped thread\n");
7223 reset_ecs (ecs, tp);
7224 switch_to_thread (tp->ptid);
7226 stop_pc = regcache_read_pc (get_thread_regcache (tp->ptid));
7227 frame = get_current_frame ();
7229 /* If the PC of the thread we were trying to single-step has
7230 changed, then that thread has trapped or been signaled, but the
7231 event has not been reported to GDB yet. Re-poll the target
7232 looking for this particular thread's event (i.e. temporarily
7233 enable schedlock) by:
7235 - setting a break at the current PC
7236 - resuming that particular thread, only (by setting trap
7239 This prevents us continuously moving the single-step breakpoint
7240 forward, one instruction at a time, overstepping. */
7242 if (stop_pc != tp->prev_pc)
7247 fprintf_unfiltered (gdb_stdlog,
7248 "infrun: expected thread advanced also (%s -> %s)\n",
7249 paddress (target_gdbarch (), tp->prev_pc),
7250 paddress (target_gdbarch (), stop_pc));
7252 /* Clear the info of the previous step-over, as it's no longer
7253 valid (if the thread was trying to step over a breakpoint, it
7254 has already succeeded). It's what keep_going would do too,
7255 if we called it. Do this before trying to insert the sss
7256 breakpoint, otherwise if we were previously trying to step
7257 over this exact address in another thread, the breakpoint is
7259 clear_step_over_info ();
7260 tp->control.trap_expected = 0;
7262 insert_single_step_breakpoint (get_frame_arch (frame),
7263 get_frame_address_space (frame),
7267 resume_ptid = internal_resume_ptid (tp->control.stepping_command);
7268 do_target_resume (resume_ptid, 0, GDB_SIGNAL_0);
7273 fprintf_unfiltered (gdb_stdlog,
7274 "infrun: expected thread still hasn't advanced\n");
7276 keep_going_pass_signal (ecs);
7281 /* Is thread TP in the middle of (software or hardware)
7282 single-stepping? (Note the result of this function must never be
7283 passed directly as target_resume's STEP parameter.) */
7286 currently_stepping (struct thread_info *tp)
7288 return ((tp->control.step_range_end
7289 && tp->control.step_resume_breakpoint == NULL)
7290 || tp->control.trap_expected
7291 || tp->stepped_breakpoint
7292 || bpstat_should_step ());
7295 /* Inferior has stepped into a subroutine call with source code that
7296 we should not step over. Do step to the first line of code in
7300 handle_step_into_function (struct gdbarch *gdbarch,
7301 struct execution_control_state *ecs)
7303 struct compunit_symtab *cust;
7304 struct symtab_and_line stop_func_sal, sr_sal;
7306 fill_in_stop_func (gdbarch, ecs);
7308 cust = find_pc_compunit_symtab (stop_pc);
7309 if (cust != NULL && compunit_language (cust) != language_asm)
7310 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
7311 ecs->stop_func_start);
7313 stop_func_sal = find_pc_line (ecs->stop_func_start, 0);
7314 /* Use the step_resume_break to step until the end of the prologue,
7315 even if that involves jumps (as it seems to on the vax under
7317 /* If the prologue ends in the middle of a source line, continue to
7318 the end of that source line (if it is still within the function).
7319 Otherwise, just go to end of prologue. */
7320 if (stop_func_sal.end
7321 && stop_func_sal.pc != ecs->stop_func_start
7322 && stop_func_sal.end < ecs->stop_func_end)
7323 ecs->stop_func_start = stop_func_sal.end;
7325 /* Architectures which require breakpoint adjustment might not be able
7326 to place a breakpoint at the computed address. If so, the test
7327 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7328 ecs->stop_func_start to an address at which a breakpoint may be
7329 legitimately placed.
7331 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7332 made, GDB will enter an infinite loop when stepping through
7333 optimized code consisting of VLIW instructions which contain
7334 subinstructions corresponding to different source lines. On
7335 FR-V, it's not permitted to place a breakpoint on any but the
7336 first subinstruction of a VLIW instruction. When a breakpoint is
7337 set, GDB will adjust the breakpoint address to the beginning of
7338 the VLIW instruction. Thus, we need to make the corresponding
7339 adjustment here when computing the stop address. */
7341 if (gdbarch_adjust_breakpoint_address_p (gdbarch))
7343 ecs->stop_func_start
7344 = gdbarch_adjust_breakpoint_address (gdbarch,
7345 ecs->stop_func_start);
7348 if (ecs->stop_func_start == stop_pc)
7350 /* We are already there: stop now. */
7351 end_stepping_range (ecs);
7356 /* Put the step-breakpoint there and go until there. */
7357 init_sal (&sr_sal); /* initialize to zeroes */
7358 sr_sal.pc = ecs->stop_func_start;
7359 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
7360 sr_sal.pspace = get_frame_program_space (get_current_frame ());
7362 /* Do not specify what the fp should be when we stop since on
7363 some machines the prologue is where the new fp value is
7365 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal, null_frame_id);
7367 /* And make sure stepping stops right away then. */
7368 ecs->event_thread->control.step_range_end
7369 = ecs->event_thread->control.step_range_start;
7374 /* Inferior has stepped backward into a subroutine call with source
7375 code that we should not step over. Do step to the beginning of the
7376 last line of code in it. */
7379 handle_step_into_function_backward (struct gdbarch *gdbarch,
7380 struct execution_control_state *ecs)
7382 struct compunit_symtab *cust;
7383 struct symtab_and_line stop_func_sal;
7385 fill_in_stop_func (gdbarch, ecs);
7387 cust = find_pc_compunit_symtab (stop_pc);
7388 if (cust != NULL && compunit_language (cust) != language_asm)
7389 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
7390 ecs->stop_func_start);
7392 stop_func_sal = find_pc_line (stop_pc, 0);
7394 /* OK, we're just going to keep stepping here. */
7395 if (stop_func_sal.pc == stop_pc)
7397 /* We're there already. Just stop stepping now. */
7398 end_stepping_range (ecs);
7402 /* Else just reset the step range and keep going.
7403 No step-resume breakpoint, they don't work for
7404 epilogues, which can have multiple entry paths. */
7405 ecs->event_thread->control.step_range_start = stop_func_sal.pc;
7406 ecs->event_thread->control.step_range_end = stop_func_sal.end;
7412 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7413 This is used to both functions and to skip over code. */
7416 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch *gdbarch,
7417 struct symtab_and_line sr_sal,
7418 struct frame_id sr_id,
7419 enum bptype sr_type)
7421 /* There should never be more than one step-resume or longjmp-resume
7422 breakpoint per thread, so we should never be setting a new
7423 step_resume_breakpoint when one is already active. */
7424 gdb_assert (inferior_thread ()->control.step_resume_breakpoint == NULL);
7425 gdb_assert (sr_type == bp_step_resume || sr_type == bp_hp_step_resume);
7428 fprintf_unfiltered (gdb_stdlog,
7429 "infrun: inserting step-resume breakpoint at %s\n",
7430 paddress (gdbarch, sr_sal.pc));
7432 inferior_thread ()->control.step_resume_breakpoint
7433 = set_momentary_breakpoint (gdbarch, sr_sal, sr_id, sr_type);
7437 insert_step_resume_breakpoint_at_sal (struct gdbarch *gdbarch,
7438 struct symtab_and_line sr_sal,
7439 struct frame_id sr_id)
7441 insert_step_resume_breakpoint_at_sal_1 (gdbarch,
7446 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7447 This is used to skip a potential signal handler.
7449 This is called with the interrupted function's frame. The signal
7450 handler, when it returns, will resume the interrupted function at
7454 insert_hp_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
7456 struct symtab_and_line sr_sal;
7457 struct gdbarch *gdbarch;
7459 gdb_assert (return_frame != NULL);
7460 init_sal (&sr_sal); /* initialize to zeros */
7462 gdbarch = get_frame_arch (return_frame);
7463 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch, get_frame_pc (return_frame));
7464 sr_sal.section = find_pc_overlay (sr_sal.pc);
7465 sr_sal.pspace = get_frame_program_space (return_frame);
7467 insert_step_resume_breakpoint_at_sal_1 (gdbarch, sr_sal,
7468 get_stack_frame_id (return_frame),
7472 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7473 is used to skip a function after stepping into it (for "next" or if
7474 the called function has no debugging information).
7476 The current function has almost always been reached by single
7477 stepping a call or return instruction. NEXT_FRAME belongs to the
7478 current function, and the breakpoint will be set at the caller's
7481 This is a separate function rather than reusing
7482 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7483 get_prev_frame, which may stop prematurely (see the implementation
7484 of frame_unwind_caller_id for an example). */
7487 insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame)
7489 struct symtab_and_line sr_sal;
7490 struct gdbarch *gdbarch;
7492 /* We shouldn't have gotten here if we don't know where the call site
7494 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame)));
7496 init_sal (&sr_sal); /* initialize to zeros */
7498 gdbarch = frame_unwind_caller_arch (next_frame);
7499 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch,
7500 frame_unwind_caller_pc (next_frame));
7501 sr_sal.section = find_pc_overlay (sr_sal.pc);
7502 sr_sal.pspace = frame_unwind_program_space (next_frame);
7504 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal,
7505 frame_unwind_caller_id (next_frame));
7508 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7509 new breakpoint at the target of a jmp_buf. The handling of
7510 longjmp-resume uses the same mechanisms used for handling
7511 "step-resume" breakpoints. */
7514 insert_longjmp_resume_breakpoint (struct gdbarch *gdbarch, CORE_ADDR pc)
7516 /* There should never be more than one longjmp-resume breakpoint per
7517 thread, so we should never be setting a new
7518 longjmp_resume_breakpoint when one is already active. */
7519 gdb_assert (inferior_thread ()->control.exception_resume_breakpoint == NULL);
7522 fprintf_unfiltered (gdb_stdlog,
7523 "infrun: inserting longjmp-resume breakpoint at %s\n",
7524 paddress (gdbarch, pc));
7526 inferior_thread ()->control.exception_resume_breakpoint =
7527 set_momentary_breakpoint_at_pc (gdbarch, pc, bp_longjmp_resume);
7530 /* Insert an exception resume breakpoint. TP is the thread throwing
7531 the exception. The block B is the block of the unwinder debug hook
7532 function. FRAME is the frame corresponding to the call to this
7533 function. SYM is the symbol of the function argument holding the
7534 target PC of the exception. */
7537 insert_exception_resume_breakpoint (struct thread_info *tp,
7538 const struct block *b,
7539 struct frame_info *frame,
7544 struct block_symbol vsym;
7545 struct value *value;
7547 struct breakpoint *bp;
7549 vsym = lookup_symbol (SYMBOL_LINKAGE_NAME (sym), b, VAR_DOMAIN, NULL);
7550 value = read_var_value (vsym.symbol, vsym.block, frame);
7551 /* If the value was optimized out, revert to the old behavior. */
7552 if (! value_optimized_out (value))
7554 handler = value_as_address (value);
7557 fprintf_unfiltered (gdb_stdlog,
7558 "infrun: exception resume at %lx\n",
7559 (unsigned long) handler);
7561 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
7562 handler, bp_exception_resume);
7564 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7567 bp->thread = tp->global_num;
7568 inferior_thread ()->control.exception_resume_breakpoint = bp;
7571 CATCH (e, RETURN_MASK_ERROR)
7573 /* We want to ignore errors here. */
7578 /* A helper for check_exception_resume that sets an
7579 exception-breakpoint based on a SystemTap probe. */
7582 insert_exception_resume_from_probe (struct thread_info *tp,
7583 const struct bound_probe *probe,
7584 struct frame_info *frame)
7586 struct value *arg_value;
7588 struct breakpoint *bp;
7590 arg_value = probe_safe_evaluate_at_pc (frame, 1);
7594 handler = value_as_address (arg_value);
7597 fprintf_unfiltered (gdb_stdlog,
7598 "infrun: exception resume at %s\n",
7599 paddress (get_objfile_arch (probe->objfile),
7602 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
7603 handler, bp_exception_resume);
7604 bp->thread = tp->global_num;
7605 inferior_thread ()->control.exception_resume_breakpoint = bp;
7608 /* This is called when an exception has been intercepted. Check to
7609 see whether the exception's destination is of interest, and if so,
7610 set an exception resume breakpoint there. */
7613 check_exception_resume (struct execution_control_state *ecs,
7614 struct frame_info *frame)
7616 struct bound_probe probe;
7617 struct symbol *func;
7619 /* First see if this exception unwinding breakpoint was set via a
7620 SystemTap probe point. If so, the probe has two arguments: the
7621 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7622 set a breakpoint there. */
7623 probe = find_probe_by_pc (get_frame_pc (frame));
7626 insert_exception_resume_from_probe (ecs->event_thread, &probe, frame);
7630 func = get_frame_function (frame);
7636 const struct block *b;
7637 struct block_iterator iter;
7641 /* The exception breakpoint is a thread-specific breakpoint on
7642 the unwinder's debug hook, declared as:
7644 void _Unwind_DebugHook (void *cfa, void *handler);
7646 The CFA argument indicates the frame to which control is
7647 about to be transferred. HANDLER is the destination PC.
7649 We ignore the CFA and set a temporary breakpoint at HANDLER.
7650 This is not extremely efficient but it avoids issues in gdb
7651 with computing the DWARF CFA, and it also works even in weird
7652 cases such as throwing an exception from inside a signal
7655 b = SYMBOL_BLOCK_VALUE (func);
7656 ALL_BLOCK_SYMBOLS (b, iter, sym)
7658 if (!SYMBOL_IS_ARGUMENT (sym))
7665 insert_exception_resume_breakpoint (ecs->event_thread,
7671 CATCH (e, RETURN_MASK_ERROR)
7678 stop_waiting (struct execution_control_state *ecs)
7681 fprintf_unfiltered (gdb_stdlog, "infrun: stop_waiting\n");
7683 clear_step_over_info ();
7685 /* Let callers know we don't want to wait for the inferior anymore. */
7686 ecs->wait_some_more = 0;
7688 /* If all-stop, but the target is always in non-stop mode, stop all
7689 threads now that we're presenting the stop to the user. */
7690 if (!non_stop && target_is_non_stop_p ())
7691 stop_all_threads ();
7694 /* Like keep_going, but passes the signal to the inferior, even if the
7695 signal is set to nopass. */
7698 keep_going_pass_signal (struct execution_control_state *ecs)
7700 /* Make sure normal_stop is called if we get a QUIT handled before
7702 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
7704 gdb_assert (ptid_equal (ecs->event_thread->ptid, inferior_ptid));
7705 gdb_assert (!ecs->event_thread->resumed);
7707 /* Save the pc before execution, to compare with pc after stop. */
7708 ecs->event_thread->prev_pc
7709 = regcache_read_pc (get_thread_regcache (ecs->ptid));
7711 if (ecs->event_thread->control.trap_expected)
7713 struct thread_info *tp = ecs->event_thread;
7716 fprintf_unfiltered (gdb_stdlog,
7717 "infrun: %s has trap_expected set, "
7718 "resuming to collect trap\n",
7719 target_pid_to_str (tp->ptid));
7721 /* We haven't yet gotten our trap, and either: intercepted a
7722 non-signal event (e.g., a fork); or took a signal which we
7723 are supposed to pass through to the inferior. Simply
7725 discard_cleanups (old_cleanups);
7726 resume (ecs->event_thread->suspend.stop_signal);
7728 else if (step_over_info_valid_p ())
7730 /* Another thread is stepping over a breakpoint in-line. If
7731 this thread needs a step-over too, queue the request. In
7732 either case, this resume must be deferred for later. */
7733 struct thread_info *tp = ecs->event_thread;
7735 if (ecs->hit_singlestep_breakpoint
7736 || thread_still_needs_step_over (tp))
7739 fprintf_unfiltered (gdb_stdlog,
7740 "infrun: step-over already in progress: "
7741 "step-over for %s deferred\n",
7742 target_pid_to_str (tp->ptid));
7743 thread_step_over_chain_enqueue (tp);
7748 fprintf_unfiltered (gdb_stdlog,
7749 "infrun: step-over in progress: "
7750 "resume of %s deferred\n",
7751 target_pid_to_str (tp->ptid));
7754 discard_cleanups (old_cleanups);
7758 struct regcache *regcache = get_current_regcache ();
7761 step_over_what step_what;
7763 /* Either the trap was not expected, but we are continuing
7764 anyway (if we got a signal, the user asked it be passed to
7767 We got our expected trap, but decided we should resume from
7770 We're going to run this baby now!
7772 Note that insert_breakpoints won't try to re-insert
7773 already inserted breakpoints. Therefore, we don't
7774 care if breakpoints were already inserted, or not. */
7776 /* If we need to step over a breakpoint, and we're not using
7777 displaced stepping to do so, insert all breakpoints
7778 (watchpoints, etc.) but the one we're stepping over, step one
7779 instruction, and then re-insert the breakpoint when that step
7782 step_what = thread_still_needs_step_over (ecs->event_thread);
7784 remove_bp = (ecs->hit_singlestep_breakpoint
7785 || (step_what & STEP_OVER_BREAKPOINT));
7786 remove_wps = (step_what & STEP_OVER_WATCHPOINT);
7788 /* We can't use displaced stepping if we need to step past a
7789 watchpoint. The instruction copied to the scratch pad would
7790 still trigger the watchpoint. */
7792 && (remove_wps || !use_displaced_stepping (ecs->event_thread)))
7794 set_step_over_info (get_regcache_aspace (regcache),
7795 regcache_read_pc (regcache), remove_wps,
7796 ecs->event_thread->global_num);
7798 else if (remove_wps)
7799 set_step_over_info (NULL, 0, remove_wps, -1);
7801 /* If we now need to do an in-line step-over, we need to stop
7802 all other threads. Note this must be done before
7803 insert_breakpoints below, because that removes the breakpoint
7804 we're about to step over, otherwise other threads could miss
7806 if (step_over_info_valid_p () && target_is_non_stop_p ())
7807 stop_all_threads ();
7809 /* Stop stepping if inserting breakpoints fails. */
7812 insert_breakpoints ();
7814 CATCH (e, RETURN_MASK_ERROR)
7816 exception_print (gdb_stderr, e);
7818 discard_cleanups (old_cleanups);
7823 ecs->event_thread->control.trap_expected = (remove_bp || remove_wps);
7825 discard_cleanups (old_cleanups);
7826 resume (ecs->event_thread->suspend.stop_signal);
7829 prepare_to_wait (ecs);
7832 /* Called when we should continue running the inferior, because the
7833 current event doesn't cause a user visible stop. This does the
7834 resuming part; waiting for the next event is done elsewhere. */
7837 keep_going (struct execution_control_state *ecs)
7839 if (ecs->event_thread->control.trap_expected
7840 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
7841 ecs->event_thread->control.trap_expected = 0;
7843 if (!signal_program[ecs->event_thread->suspend.stop_signal])
7844 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
7845 keep_going_pass_signal (ecs);
7848 /* This function normally comes after a resume, before
7849 handle_inferior_event exits. It takes care of any last bits of
7850 housekeeping, and sets the all-important wait_some_more flag. */
7853 prepare_to_wait (struct execution_control_state *ecs)
7856 fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n");
7858 ecs->wait_some_more = 1;
7860 if (!target_is_async_p ())
7861 mark_infrun_async_event_handler ();
7864 /* We are done with the step range of a step/next/si/ni command.
7865 Called once for each n of a "step n" operation. */
7868 end_stepping_range (struct execution_control_state *ecs)
7870 ecs->event_thread->control.stop_step = 1;
7874 /* Several print_*_reason functions to print why the inferior has stopped.
7875 We always print something when the inferior exits, or receives a signal.
7876 The rest of the cases are dealt with later on in normal_stop and
7877 print_it_typical. Ideally there should be a call to one of these
7878 print_*_reason functions functions from handle_inferior_event each time
7879 stop_waiting is called.
7881 Note that we don't call these directly, instead we delegate that to
7882 the interpreters, through observers. Interpreters then call these
7883 with whatever uiout is right. */
7886 print_end_stepping_range_reason (struct ui_out *uiout)
7888 /* For CLI-like interpreters, print nothing. */
7890 if (ui_out_is_mi_like_p (uiout))
7892 ui_out_field_string (uiout, "reason",
7893 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE));
7898 print_signal_exited_reason (struct ui_out *uiout, enum gdb_signal siggnal)
7900 annotate_signalled ();
7901 if (ui_out_is_mi_like_p (uiout))
7903 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED));
7904 ui_out_text (uiout, "\nProgram terminated with signal ");
7905 annotate_signal_name ();
7906 ui_out_field_string (uiout, "signal-name",
7907 gdb_signal_to_name (siggnal));
7908 annotate_signal_name_end ();
7909 ui_out_text (uiout, ", ");
7910 annotate_signal_string ();
7911 ui_out_field_string (uiout, "signal-meaning",
7912 gdb_signal_to_string (siggnal));
7913 annotate_signal_string_end ();
7914 ui_out_text (uiout, ".\n");
7915 ui_out_text (uiout, "The program no longer exists.\n");
7919 print_exited_reason (struct ui_out *uiout, int exitstatus)
7921 struct inferior *inf = current_inferior ();
7922 const char *pidstr = target_pid_to_str (pid_to_ptid (inf->pid));
7924 annotate_exited (exitstatus);
7927 if (ui_out_is_mi_like_p (uiout))
7928 ui_out_field_string (uiout, "reason",
7929 async_reason_lookup (EXEC_ASYNC_EXITED));
7930 ui_out_text (uiout, "[Inferior ");
7931 ui_out_text (uiout, plongest (inf->num));
7932 ui_out_text (uiout, " (");
7933 ui_out_text (uiout, pidstr);
7934 ui_out_text (uiout, ") exited with code ");
7935 ui_out_field_fmt (uiout, "exit-code", "0%o", (unsigned int) exitstatus);
7936 ui_out_text (uiout, "]\n");
7940 if (ui_out_is_mi_like_p (uiout))
7942 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY));
7943 ui_out_text (uiout, "[Inferior ");
7944 ui_out_text (uiout, plongest (inf->num));
7945 ui_out_text (uiout, " (");
7946 ui_out_text (uiout, pidstr);
7947 ui_out_text (uiout, ") exited normally]\n");
7951 /* Some targets/architectures can do extra processing/display of
7952 segmentation faults. E.g., Intel MPX boundary faults.
7953 Call the architecture dependent function to handle the fault. */
7956 handle_segmentation_fault (struct ui_out *uiout)
7958 struct regcache *regcache = get_current_regcache ();
7959 struct gdbarch *gdbarch = get_regcache_arch (regcache);
7961 if (gdbarch_handle_segmentation_fault_p (gdbarch))
7962 gdbarch_handle_segmentation_fault (gdbarch, uiout);
7966 print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal)
7968 struct thread_info *thr = inferior_thread ();
7972 if (ui_out_is_mi_like_p (uiout))
7974 else if (show_thread_that_caused_stop ())
7978 ui_out_text (uiout, "\nThread ");
7979 ui_out_field_fmt (uiout, "thread-id", "%s", print_thread_id (thr));
7981 name = thr->name != NULL ? thr->name : target_thread_name (thr);
7984 ui_out_text (uiout, " \"");
7985 ui_out_field_fmt (uiout, "name", "%s", name);
7986 ui_out_text (uiout, "\"");
7990 ui_out_text (uiout, "\nProgram");
7992 if (siggnal == GDB_SIGNAL_0 && !ui_out_is_mi_like_p (uiout))
7993 ui_out_text (uiout, " stopped");
7996 ui_out_text (uiout, " received signal ");
7997 annotate_signal_name ();
7998 if (ui_out_is_mi_like_p (uiout))
8000 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
8001 ui_out_field_string (uiout, "signal-name",
8002 gdb_signal_to_name (siggnal));
8003 annotate_signal_name_end ();
8004 ui_out_text (uiout, ", ");
8005 annotate_signal_string ();
8006 ui_out_field_string (uiout, "signal-meaning",
8007 gdb_signal_to_string (siggnal));
8009 if (siggnal == GDB_SIGNAL_SEGV)
8010 handle_segmentation_fault (uiout);
8012 annotate_signal_string_end ();
8014 ui_out_text (uiout, ".\n");
8018 print_no_history_reason (struct ui_out *uiout)
8020 ui_out_text (uiout, "\nNo more reverse-execution history.\n");
8023 /* Print current location without a level number, if we have changed
8024 functions or hit a breakpoint. Print source line if we have one.
8025 bpstat_print contains the logic deciding in detail what to print,
8026 based on the event(s) that just occurred. */
8029 print_stop_location (struct target_waitstatus *ws)
8032 enum print_what source_flag;
8033 int do_frame_printing = 1;
8034 struct thread_info *tp = inferior_thread ();
8036 bpstat_ret = bpstat_print (tp->control.stop_bpstat, ws->kind);
8040 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8041 should) carry around the function and does (or should) use
8042 that when doing a frame comparison. */
8043 if (tp->control.stop_step
8044 && frame_id_eq (tp->control.step_frame_id,
8045 get_frame_id (get_current_frame ()))
8046 && tp->control.step_start_function == find_pc_function (stop_pc))
8048 /* Finished step, just print source line. */
8049 source_flag = SRC_LINE;
8053 /* Print location and source line. */
8054 source_flag = SRC_AND_LOC;
8057 case PRINT_SRC_AND_LOC:
8058 /* Print location and source line. */
8059 source_flag = SRC_AND_LOC;
8061 case PRINT_SRC_ONLY:
8062 source_flag = SRC_LINE;
8065 /* Something bogus. */
8066 source_flag = SRC_LINE;
8067 do_frame_printing = 0;
8070 internal_error (__FILE__, __LINE__, _("Unknown value."));
8073 /* The behavior of this routine with respect to the source
8075 SRC_LINE: Print only source line
8076 LOCATION: Print only location
8077 SRC_AND_LOC: Print location and source line. */
8078 if (do_frame_printing)
8079 print_stack_frame (get_selected_frame (NULL), 0, source_flag, 1);
8085 print_stop_event (struct ui_out *uiout)
8087 struct target_waitstatus last;
8089 struct thread_info *tp;
8091 get_last_target_status (&last_ptid, &last);
8094 scoped_restore save_uiout = make_scoped_restore (¤t_uiout, uiout);
8096 print_stop_location (&last);
8098 /* Display the auto-display expressions. */
8102 tp = inferior_thread ();
8103 if (tp->thread_fsm != NULL
8104 && thread_fsm_finished_p (tp->thread_fsm))
8106 struct return_value_info *rv;
8108 rv = thread_fsm_return_value (tp->thread_fsm);
8110 print_return_value (uiout, rv);
8117 maybe_remove_breakpoints (void)
8119 if (!breakpoints_should_be_inserted_now () && target_has_execution)
8121 if (remove_breakpoints ())
8123 target_terminal_ours_for_output ();
8124 printf_filtered (_("Cannot remove breakpoints because "
8125 "program is no longer writable.\nFurther "
8126 "execution is probably impossible.\n"));
8131 /* The execution context that just caused a normal stop. */
8138 /* The event PTID. */
8142 /* If stopp for a thread event, this is the thread that caused the
8144 struct thread_info *thread;
8146 /* The inferior that caused the stop. */
8150 /* Returns a new stop context. If stopped for a thread event, this
8151 takes a strong reference to the thread. */
8153 static struct stop_context *
8154 save_stop_context (void)
8156 struct stop_context *sc = XNEW (struct stop_context);
8158 sc->stop_id = get_stop_id ();
8159 sc->ptid = inferior_ptid;
8160 sc->inf_num = current_inferior ()->num;
8162 if (!ptid_equal (inferior_ptid, null_ptid))
8164 /* Take a strong reference so that the thread can't be deleted
8166 sc->thread = inferior_thread ();
8167 sc->thread->refcount++;
8175 /* Release a stop context previously created with save_stop_context.
8176 Releases the strong reference to the thread as well. */
8179 release_stop_context_cleanup (void *arg)
8181 struct stop_context *sc = (struct stop_context *) arg;
8183 if (sc->thread != NULL)
8184 sc->thread->refcount--;
8188 /* Return true if the current context no longer matches the saved stop
8192 stop_context_changed (struct stop_context *prev)
8194 if (!ptid_equal (prev->ptid, inferior_ptid))
8196 if (prev->inf_num != current_inferior ()->num)
8198 if (prev->thread != NULL && prev->thread->state != THREAD_STOPPED)
8200 if (get_stop_id () != prev->stop_id)
8210 struct target_waitstatus last;
8212 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
8215 get_last_target_status (&last_ptid, &last);
8219 /* If an exception is thrown from this point on, make sure to
8220 propagate GDB's knowledge of the executing state to the
8221 frontend/user running state. A QUIT is an easy exception to see
8222 here, so do this before any filtered output. */
8224 make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
8225 else if (last.kind == TARGET_WAITKIND_SIGNALLED
8226 || last.kind == TARGET_WAITKIND_EXITED)
8228 /* On some targets, we may still have live threads in the
8229 inferior when we get a process exit event. E.g., for
8230 "checkpoint", when the current checkpoint/fork exits,
8231 linux-fork.c automatically switches to another fork from
8232 within target_mourn_inferior. */
8233 if (!ptid_equal (inferior_ptid, null_ptid))
8235 pid_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
8236 make_cleanup (finish_thread_state_cleanup, &pid_ptid);
8239 else if (last.kind != TARGET_WAITKIND_NO_RESUMED)
8240 make_cleanup (finish_thread_state_cleanup, &inferior_ptid);
8242 /* As we're presenting a stop, and potentially removing breakpoints,
8243 update the thread list so we can tell whether there are threads
8244 running on the target. With target remote, for example, we can
8245 only learn about new threads when we explicitly update the thread
8246 list. Do this before notifying the interpreters about signal
8247 stops, end of stepping ranges, etc., so that the "new thread"
8248 output is emitted before e.g., "Program received signal FOO",
8249 instead of after. */
8250 update_thread_list ();
8252 if (last.kind == TARGET_WAITKIND_STOPPED && stopped_by_random_signal)
8253 observer_notify_signal_received (inferior_thread ()->suspend.stop_signal);
8255 /* As with the notification of thread events, we want to delay
8256 notifying the user that we've switched thread context until
8257 the inferior actually stops.
8259 There's no point in saying anything if the inferior has exited.
8260 Note that SIGNALLED here means "exited with a signal", not
8261 "received a signal".
8263 Also skip saying anything in non-stop mode. In that mode, as we
8264 don't want GDB to switch threads behind the user's back, to avoid
8265 races where the user is typing a command to apply to thread x,
8266 but GDB switches to thread y before the user finishes entering
8267 the command, fetch_inferior_event installs a cleanup to restore
8268 the current thread back to the thread the user had selected right
8269 after this event is handled, so we're not really switching, only
8270 informing of a stop. */
8272 && !ptid_equal (previous_inferior_ptid, inferior_ptid)
8273 && target_has_execution
8274 && last.kind != TARGET_WAITKIND_SIGNALLED
8275 && last.kind != TARGET_WAITKIND_EXITED
8276 && last.kind != TARGET_WAITKIND_NO_RESUMED)
8278 SWITCH_THRU_ALL_UIS ()
8280 target_terminal_ours_for_output ();
8281 printf_filtered (_("[Switching to %s]\n"),
8282 target_pid_to_str (inferior_ptid));
8283 annotate_thread_changed ();
8285 previous_inferior_ptid = inferior_ptid;
8288 if (last.kind == TARGET_WAITKIND_NO_RESUMED)
8290 SWITCH_THRU_ALL_UIS ()
8291 if (current_ui->prompt_state == PROMPT_BLOCKED)
8293 target_terminal_ours_for_output ();
8294 printf_filtered (_("No unwaited-for children left.\n"));
8298 /* Note: this depends on the update_thread_list call above. */
8299 maybe_remove_breakpoints ();
8301 /* If an auto-display called a function and that got a signal,
8302 delete that auto-display to avoid an infinite recursion. */
8304 if (stopped_by_random_signal)
8305 disable_current_display ();
8307 SWITCH_THRU_ALL_UIS ()
8309 async_enable_stdin ();
8312 /* Let the user/frontend see the threads as stopped. */
8313 do_cleanups (old_chain);
8315 /* Select innermost stack frame - i.e., current frame is frame 0,
8316 and current location is based on that. Handle the case where the
8317 dummy call is returning after being stopped. E.g. the dummy call
8318 previously hit a breakpoint. (If the dummy call returns
8319 normally, we won't reach here.) Do this before the stop hook is
8320 run, so that it doesn't get to see the temporary dummy frame,
8321 which is not where we'll present the stop. */
8322 if (has_stack_frames ())
8324 if (stop_stack_dummy == STOP_STACK_DUMMY)
8326 /* Pop the empty frame that contains the stack dummy. This
8327 also restores inferior state prior to the call (struct
8328 infcall_suspend_state). */
8329 struct frame_info *frame = get_current_frame ();
8331 gdb_assert (get_frame_type (frame) == DUMMY_FRAME);
8333 /* frame_pop calls reinit_frame_cache as the last thing it
8334 does which means there's now no selected frame. */
8337 select_frame (get_current_frame ());
8339 /* Set the current source location. */
8340 set_current_sal_from_frame (get_current_frame ());
8343 /* Look up the hook_stop and run it (CLI internally handles problem
8344 of stop_command's pre-hook not existing). */
8345 if (stop_command != NULL)
8347 struct stop_context *saved_context = save_stop_context ();
8348 struct cleanup *old_chain
8349 = make_cleanup (release_stop_context_cleanup, saved_context);
8351 catch_errors (hook_stop_stub, stop_command,
8352 "Error while running hook_stop:\n", RETURN_MASK_ALL);
8354 /* If the stop hook resumes the target, then there's no point in
8355 trying to notify about the previous stop; its context is
8356 gone. Likewise if the command switches thread or inferior --
8357 the observers would print a stop for the wrong
8359 if (stop_context_changed (saved_context))
8361 do_cleanups (old_chain);
8364 do_cleanups (old_chain);
8367 /* Notify observers about the stop. This is where the interpreters
8368 print the stop event. */
8369 if (!ptid_equal (inferior_ptid, null_ptid))
8370 observer_notify_normal_stop (inferior_thread ()->control.stop_bpstat,
8373 observer_notify_normal_stop (NULL, stop_print_frame);
8375 annotate_stopped ();
8377 if (target_has_execution)
8379 if (last.kind != TARGET_WAITKIND_SIGNALLED
8380 && last.kind != TARGET_WAITKIND_EXITED)
8381 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8382 Delete any breakpoint that is to be deleted at the next stop. */
8383 breakpoint_auto_delete (inferior_thread ()->control.stop_bpstat);
8386 /* Try to get rid of automatically added inferiors that are no
8387 longer needed. Keeping those around slows down things linearly.
8388 Note that this never removes the current inferior. */
8395 hook_stop_stub (void *cmd)
8397 execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
8402 signal_stop_state (int signo)
8404 return signal_stop[signo];
8408 signal_print_state (int signo)
8410 return signal_print[signo];
8414 signal_pass_state (int signo)
8416 return signal_program[signo];
8420 signal_cache_update (int signo)
8424 for (signo = 0; signo < (int) GDB_SIGNAL_LAST; signo++)
8425 signal_cache_update (signo);
8430 signal_pass[signo] = (signal_stop[signo] == 0
8431 && signal_print[signo] == 0
8432 && signal_program[signo] == 1
8433 && signal_catch[signo] == 0);
8437 signal_stop_update (int signo, int state)
8439 int ret = signal_stop[signo];
8441 signal_stop[signo] = state;
8442 signal_cache_update (signo);
8447 signal_print_update (int signo, int state)
8449 int ret = signal_print[signo];
8451 signal_print[signo] = state;
8452 signal_cache_update (signo);
8457 signal_pass_update (int signo, int state)
8459 int ret = signal_program[signo];
8461 signal_program[signo] = state;
8462 signal_cache_update (signo);
8466 /* Update the global 'signal_catch' from INFO and notify the
8470 signal_catch_update (const unsigned int *info)
8474 for (i = 0; i < GDB_SIGNAL_LAST; ++i)
8475 signal_catch[i] = info[i] > 0;
8476 signal_cache_update (-1);
8477 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
8481 sig_print_header (void)
8483 printf_filtered (_("Signal Stop\tPrint\tPass "
8484 "to program\tDescription\n"));
8488 sig_print_info (enum gdb_signal oursig)
8490 const char *name = gdb_signal_to_name (oursig);
8491 int name_padding = 13 - strlen (name);
8493 if (name_padding <= 0)
8496 printf_filtered ("%s", name);
8497 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
8498 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
8499 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
8500 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
8501 printf_filtered ("%s\n", gdb_signal_to_string (oursig));
8504 /* Specify how various signals in the inferior should be handled. */
8507 handle_command (char *args, int from_tty)
8510 int digits, wordlen;
8511 int sigfirst, signum, siglast;
8512 enum gdb_signal oursig;
8515 unsigned char *sigs;
8516 struct cleanup *old_chain;
8520 error_no_arg (_("signal to handle"));
8523 /* Allocate and zero an array of flags for which signals to handle. */
8525 nsigs = (int) GDB_SIGNAL_LAST;
8526 sigs = (unsigned char *) alloca (nsigs);
8527 memset (sigs, 0, nsigs);
8529 /* Break the command line up into args. */
8531 argv = gdb_buildargv (args);
8532 old_chain = make_cleanup_freeargv (argv);
8534 /* Walk through the args, looking for signal oursigs, signal names, and
8535 actions. Signal numbers and signal names may be interspersed with
8536 actions, with the actions being performed for all signals cumulatively
8537 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8539 while (*argv != NULL)
8541 wordlen = strlen (*argv);
8542 for (digits = 0; isdigit ((*argv)[digits]); digits++)
8546 sigfirst = siglast = -1;
8548 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
8550 /* Apply action to all signals except those used by the
8551 debugger. Silently skip those. */
8554 siglast = nsigs - 1;
8556 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
8558 SET_SIGS (nsigs, sigs, signal_stop);
8559 SET_SIGS (nsigs, sigs, signal_print);
8561 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
8563 UNSET_SIGS (nsigs, sigs, signal_program);
8565 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
8567 SET_SIGS (nsigs, sigs, signal_print);
8569 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
8571 SET_SIGS (nsigs, sigs, signal_program);
8573 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
8575 UNSET_SIGS (nsigs, sigs, signal_stop);
8577 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
8579 SET_SIGS (nsigs, sigs, signal_program);
8581 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
8583 UNSET_SIGS (nsigs, sigs, signal_print);
8584 UNSET_SIGS (nsigs, sigs, signal_stop);
8586 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
8588 UNSET_SIGS (nsigs, sigs, signal_program);
8590 else if (digits > 0)
8592 /* It is numeric. The numeric signal refers to our own
8593 internal signal numbering from target.h, not to host/target
8594 signal number. This is a feature; users really should be
8595 using symbolic names anyway, and the common ones like
8596 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8598 sigfirst = siglast = (int)
8599 gdb_signal_from_command (atoi (*argv));
8600 if ((*argv)[digits] == '-')
8603 gdb_signal_from_command (atoi ((*argv) + digits + 1));
8605 if (sigfirst > siglast)
8607 /* Bet he didn't figure we'd think of this case... */
8615 oursig = gdb_signal_from_name (*argv);
8616 if (oursig != GDB_SIGNAL_UNKNOWN)
8618 sigfirst = siglast = (int) oursig;
8622 /* Not a number and not a recognized flag word => complain. */
8623 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv);
8627 /* If any signal numbers or symbol names were found, set flags for
8628 which signals to apply actions to. */
8630 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
8632 switch ((enum gdb_signal) signum)
8634 case GDB_SIGNAL_TRAP:
8635 case GDB_SIGNAL_INT:
8636 if (!allsigs && !sigs[signum])
8638 if (query (_("%s is used by the debugger.\n\
8639 Are you sure you want to change it? "),
8640 gdb_signal_to_name ((enum gdb_signal) signum)))
8646 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8647 gdb_flush (gdb_stdout);
8652 case GDB_SIGNAL_DEFAULT:
8653 case GDB_SIGNAL_UNKNOWN:
8654 /* Make sure that "all" doesn't print these. */
8665 for (signum = 0; signum < nsigs; signum++)
8668 signal_cache_update (-1);
8669 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
8670 target_program_signals ((int) GDB_SIGNAL_LAST, signal_program);
8674 /* Show the results. */
8675 sig_print_header ();
8676 for (; signum < nsigs; signum++)
8678 sig_print_info ((enum gdb_signal) signum);
8684 do_cleanups (old_chain);
8687 /* Complete the "handle" command. */
8689 static VEC (char_ptr) *
8690 handle_completer (struct cmd_list_element *ignore,
8691 const char *text, const char *word)
8693 VEC (char_ptr) *vec_signals, *vec_keywords, *return_val;
8694 static const char * const keywords[] =
8708 vec_signals = signal_completer (ignore, text, word);
8709 vec_keywords = complete_on_enum (keywords, word, word);
8711 return_val = VEC_merge (char_ptr, vec_signals, vec_keywords);
8712 VEC_free (char_ptr, vec_signals);
8713 VEC_free (char_ptr, vec_keywords);
8718 gdb_signal_from_command (int num)
8720 if (num >= 1 && num <= 15)
8721 return (enum gdb_signal) num;
8722 error (_("Only signals 1-15 are valid as numeric signals.\n\
8723 Use \"info signals\" for a list of symbolic signals."));
8726 /* Print current contents of the tables set by the handle command.
8727 It is possible we should just be printing signals actually used
8728 by the current target (but for things to work right when switching
8729 targets, all signals should be in the signal tables). */
8732 signals_info (char *signum_exp, int from_tty)
8734 enum gdb_signal oursig;
8736 sig_print_header ();
8740 /* First see if this is a symbol name. */
8741 oursig = gdb_signal_from_name (signum_exp);
8742 if (oursig == GDB_SIGNAL_UNKNOWN)
8744 /* No, try numeric. */
8746 gdb_signal_from_command (parse_and_eval_long (signum_exp));
8748 sig_print_info (oursig);
8752 printf_filtered ("\n");
8753 /* These ugly casts brought to you by the native VAX compiler. */
8754 for (oursig = GDB_SIGNAL_FIRST;
8755 (int) oursig < (int) GDB_SIGNAL_LAST;
8756 oursig = (enum gdb_signal) ((int) oursig + 1))
8760 if (oursig != GDB_SIGNAL_UNKNOWN
8761 && oursig != GDB_SIGNAL_DEFAULT && oursig != GDB_SIGNAL_0)
8762 sig_print_info (oursig);
8765 printf_filtered (_("\nUse the \"handle\" command "
8766 "to change these tables.\n"));
8769 /* The $_siginfo convenience variable is a bit special. We don't know
8770 for sure the type of the value until we actually have a chance to
8771 fetch the data. The type can change depending on gdbarch, so it is
8772 also dependent on which thread you have selected.
8774 1. making $_siginfo be an internalvar that creates a new value on
8777 2. making the value of $_siginfo be an lval_computed value. */
8779 /* This function implements the lval_computed support for reading a
8783 siginfo_value_read (struct value *v)
8785 LONGEST transferred;
8787 /* If we can access registers, so can we access $_siginfo. Likewise
8789 validate_registers_access ();
8792 target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO,
8794 value_contents_all_raw (v),
8796 TYPE_LENGTH (value_type (v)));
8798 if (transferred != TYPE_LENGTH (value_type (v)))
8799 error (_("Unable to read siginfo"));
8802 /* This function implements the lval_computed support for writing a
8806 siginfo_value_write (struct value *v, struct value *fromval)
8808 LONGEST transferred;
8810 /* If we can access registers, so can we access $_siginfo. Likewise
8812 validate_registers_access ();
8814 transferred = target_write (¤t_target,
8815 TARGET_OBJECT_SIGNAL_INFO,
8817 value_contents_all_raw (fromval),
8819 TYPE_LENGTH (value_type (fromval)));
8821 if (transferred != TYPE_LENGTH (value_type (fromval)))
8822 error (_("Unable to write siginfo"));
8825 static const struct lval_funcs siginfo_value_funcs =
8831 /* Return a new value with the correct type for the siginfo object of
8832 the current thread using architecture GDBARCH. Return a void value
8833 if there's no object available. */
8835 static struct value *
8836 siginfo_make_value (struct gdbarch *gdbarch, struct internalvar *var,
8839 if (target_has_stack
8840 && !ptid_equal (inferior_ptid, null_ptid)
8841 && gdbarch_get_siginfo_type_p (gdbarch))
8843 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8845 return allocate_computed_value (type, &siginfo_value_funcs, NULL);
8848 return allocate_value (builtin_type (gdbarch)->builtin_void);
8852 /* infcall_suspend_state contains state about the program itself like its
8853 registers and any signal it received when it last stopped.
8854 This state must be restored regardless of how the inferior function call
8855 ends (either successfully, or after it hits a breakpoint or signal)
8856 if the program is to properly continue where it left off. */
8858 struct infcall_suspend_state
8860 struct thread_suspend_state thread_suspend;
8864 struct regcache *registers;
8866 /* Format of SIGINFO_DATA or NULL if it is not present. */
8867 struct gdbarch *siginfo_gdbarch;
8869 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8870 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8871 content would be invalid. */
8872 gdb_byte *siginfo_data;
8875 struct infcall_suspend_state *
8876 save_infcall_suspend_state (void)
8878 struct infcall_suspend_state *inf_state;
8879 struct thread_info *tp = inferior_thread ();
8880 struct regcache *regcache = get_current_regcache ();
8881 struct gdbarch *gdbarch = get_regcache_arch (regcache);
8882 gdb_byte *siginfo_data = NULL;
8884 if (gdbarch_get_siginfo_type_p (gdbarch))
8886 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8887 size_t len = TYPE_LENGTH (type);
8888 struct cleanup *back_to;
8890 siginfo_data = (gdb_byte *) xmalloc (len);
8891 back_to = make_cleanup (xfree, siginfo_data);
8893 if (target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
8894 siginfo_data, 0, len) == len)
8895 discard_cleanups (back_to);
8898 /* Errors ignored. */
8899 do_cleanups (back_to);
8900 siginfo_data = NULL;
8904 inf_state = XCNEW (struct infcall_suspend_state);
8908 inf_state->siginfo_gdbarch = gdbarch;
8909 inf_state->siginfo_data = siginfo_data;
8912 inf_state->thread_suspend = tp->suspend;
8914 /* run_inferior_call will not use the signal due to its `proceed' call with
8915 GDB_SIGNAL_0 anyway. */
8916 tp->suspend.stop_signal = GDB_SIGNAL_0;
8918 inf_state->stop_pc = stop_pc;
8920 inf_state->registers = regcache_dup (regcache);
8925 /* Restore inferior session state to INF_STATE. */
8928 restore_infcall_suspend_state (struct infcall_suspend_state *inf_state)
8930 struct thread_info *tp = inferior_thread ();
8931 struct regcache *regcache = get_current_regcache ();
8932 struct gdbarch *gdbarch = get_regcache_arch (regcache);
8934 tp->suspend = inf_state->thread_suspend;
8936 stop_pc = inf_state->stop_pc;
8938 if (inf_state->siginfo_gdbarch == gdbarch)
8940 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8942 /* Errors ignored. */
8943 target_write (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
8944 inf_state->siginfo_data, 0, TYPE_LENGTH (type));
8947 /* The inferior can be gone if the user types "print exit(0)"
8948 (and perhaps other times). */
8949 if (target_has_execution)
8950 /* NB: The register write goes through to the target. */
8951 regcache_cpy (regcache, inf_state->registers);
8953 discard_infcall_suspend_state (inf_state);
8957 do_restore_infcall_suspend_state_cleanup (void *state)
8959 restore_infcall_suspend_state ((struct infcall_suspend_state *) state);
8963 make_cleanup_restore_infcall_suspend_state
8964 (struct infcall_suspend_state *inf_state)
8966 return make_cleanup (do_restore_infcall_suspend_state_cleanup, inf_state);
8970 discard_infcall_suspend_state (struct infcall_suspend_state *inf_state)
8972 regcache_xfree (inf_state->registers);
8973 xfree (inf_state->siginfo_data);
8978 get_infcall_suspend_state_regcache (struct infcall_suspend_state *inf_state)
8980 return inf_state->registers;
8983 /* infcall_control_state contains state regarding gdb's control of the
8984 inferior itself like stepping control. It also contains session state like
8985 the user's currently selected frame. */
8987 struct infcall_control_state
8989 struct thread_control_state thread_control;
8990 struct inferior_control_state inferior_control;
8993 enum stop_stack_kind stop_stack_dummy;
8994 int stopped_by_random_signal;
8996 /* ID if the selected frame when the inferior function call was made. */
8997 struct frame_id selected_frame_id;
9000 /* Save all of the information associated with the inferior<==>gdb
9003 struct infcall_control_state *
9004 save_infcall_control_state (void)
9006 struct infcall_control_state *inf_status =
9007 XNEW (struct infcall_control_state);
9008 struct thread_info *tp = inferior_thread ();
9009 struct inferior *inf = current_inferior ();
9011 inf_status->thread_control = tp->control;
9012 inf_status->inferior_control = inf->control;
9014 tp->control.step_resume_breakpoint = NULL;
9015 tp->control.exception_resume_breakpoint = NULL;
9017 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9018 chain. If caller's caller is walking the chain, they'll be happier if we
9019 hand them back the original chain when restore_infcall_control_state is
9021 tp->control.stop_bpstat = bpstat_copy (tp->control.stop_bpstat);
9024 inf_status->stop_stack_dummy = stop_stack_dummy;
9025 inf_status->stopped_by_random_signal = stopped_by_random_signal;
9027 inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL));
9033 restore_selected_frame (void *args)
9035 struct frame_id *fid = (struct frame_id *) args;
9036 struct frame_info *frame;
9038 frame = frame_find_by_id (*fid);
9040 /* If inf_status->selected_frame_id is NULL, there was no previously
9044 warning (_("Unable to restore previously selected frame."));
9048 select_frame (frame);
9053 /* Restore inferior session state to INF_STATUS. */
9056 restore_infcall_control_state (struct infcall_control_state *inf_status)
9058 struct thread_info *tp = inferior_thread ();
9059 struct inferior *inf = current_inferior ();
9061 if (tp->control.step_resume_breakpoint)
9062 tp->control.step_resume_breakpoint->disposition = disp_del_at_next_stop;
9064 if (tp->control.exception_resume_breakpoint)
9065 tp->control.exception_resume_breakpoint->disposition
9066 = disp_del_at_next_stop;
9068 /* Handle the bpstat_copy of the chain. */
9069 bpstat_clear (&tp->control.stop_bpstat);
9071 tp->control = inf_status->thread_control;
9072 inf->control = inf_status->inferior_control;
9075 stop_stack_dummy = inf_status->stop_stack_dummy;
9076 stopped_by_random_signal = inf_status->stopped_by_random_signal;
9078 if (target_has_stack)
9080 /* The point of catch_errors is that if the stack is clobbered,
9081 walking the stack might encounter a garbage pointer and
9082 error() trying to dereference it. */
9084 (restore_selected_frame, &inf_status->selected_frame_id,
9085 "Unable to restore previously selected frame:\n",
9086 RETURN_MASK_ERROR) == 0)
9087 /* Error in restoring the selected frame. Select the innermost
9089 select_frame (get_current_frame ());
9096 do_restore_infcall_control_state_cleanup (void *sts)
9098 restore_infcall_control_state ((struct infcall_control_state *) sts);
9102 make_cleanup_restore_infcall_control_state
9103 (struct infcall_control_state *inf_status)
9105 return make_cleanup (do_restore_infcall_control_state_cleanup, inf_status);
9109 discard_infcall_control_state (struct infcall_control_state *inf_status)
9111 if (inf_status->thread_control.step_resume_breakpoint)
9112 inf_status->thread_control.step_resume_breakpoint->disposition
9113 = disp_del_at_next_stop;
9115 if (inf_status->thread_control.exception_resume_breakpoint)
9116 inf_status->thread_control.exception_resume_breakpoint->disposition
9117 = disp_del_at_next_stop;
9119 /* See save_infcall_control_state for info on stop_bpstat. */
9120 bpstat_clear (&inf_status->thread_control.stop_bpstat);
9125 /* restore_inferior_ptid() will be used by the cleanup machinery
9126 to restore the inferior_ptid value saved in a call to
9127 save_inferior_ptid(). */
9130 restore_inferior_ptid (void *arg)
9132 ptid_t *saved_ptid_ptr = (ptid_t *) arg;
9134 inferior_ptid = *saved_ptid_ptr;
9138 /* Save the value of inferior_ptid so that it may be restored by a
9139 later call to do_cleanups(). Returns the struct cleanup pointer
9140 needed for later doing the cleanup. */
9143 save_inferior_ptid (void)
9145 ptid_t *saved_ptid_ptr = XNEW (ptid_t);
9147 *saved_ptid_ptr = inferior_ptid;
9148 return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
9154 clear_exit_convenience_vars (void)
9156 clear_internalvar (lookup_internalvar ("_exitsignal"));
9157 clear_internalvar (lookup_internalvar ("_exitcode"));
9161 /* User interface for reverse debugging:
9162 Set exec-direction / show exec-direction commands
9163 (returns error unless target implements to_set_exec_direction method). */
9165 enum exec_direction_kind execution_direction = EXEC_FORWARD;
9166 static const char exec_forward[] = "forward";
9167 static const char exec_reverse[] = "reverse";
9168 static const char *exec_direction = exec_forward;
9169 static const char *const exec_direction_names[] = {
9176 set_exec_direction_func (char *args, int from_tty,
9177 struct cmd_list_element *cmd)
9179 if (target_can_execute_reverse)
9181 if (!strcmp (exec_direction, exec_forward))
9182 execution_direction = EXEC_FORWARD;
9183 else if (!strcmp (exec_direction, exec_reverse))
9184 execution_direction = EXEC_REVERSE;
9188 exec_direction = exec_forward;
9189 error (_("Target does not support this operation."));
9194 show_exec_direction_func (struct ui_file *out, int from_tty,
9195 struct cmd_list_element *cmd, const char *value)
9197 switch (execution_direction) {
9199 fprintf_filtered (out, _("Forward.\n"));
9202 fprintf_filtered (out, _("Reverse.\n"));
9205 internal_error (__FILE__, __LINE__,
9206 _("bogus execution_direction value: %d"),
9207 (int) execution_direction);
9212 show_schedule_multiple (struct ui_file *file, int from_tty,
9213 struct cmd_list_element *c, const char *value)
9215 fprintf_filtered (file, _("Resuming the execution of threads "
9216 "of all processes is %s.\n"), value);
9219 /* Implementation of `siginfo' variable. */
9221 static const struct internalvar_funcs siginfo_funcs =
9228 /* Callback for infrun's target events source. This is marked when a
9229 thread has a pending status to process. */
9232 infrun_async_inferior_event_handler (gdb_client_data data)
9234 inferior_event_handler (INF_REG_EVENT, NULL);
9238 _initialize_infrun (void)
9242 struct cmd_list_element *c;
9244 /* Register extra event sources in the event loop. */
9245 infrun_async_inferior_event_token
9246 = create_async_event_handler (infrun_async_inferior_event_handler, NULL);
9248 add_info ("signals", signals_info, _("\
9249 What debugger does when program gets various signals.\n\
9250 Specify a signal as argument to print info on that signal only."));
9251 add_info_alias ("handle", "signals", 0);
9253 c = add_com ("handle", class_run, handle_command, _("\
9254 Specify how to handle signals.\n\
9255 Usage: handle SIGNAL [ACTIONS]\n\
9256 Args are signals and actions to apply to those signals.\n\
9257 If no actions are specified, the current settings for the specified signals\n\
9258 will be displayed instead.\n\
9260 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9261 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9262 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9263 The special arg \"all\" is recognized to mean all signals except those\n\
9264 used by the debugger, typically SIGTRAP and SIGINT.\n\
9266 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9267 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9268 Stop means reenter debugger if this signal happens (implies print).\n\
9269 Print means print a message if this signal happens.\n\
9270 Pass means let program see this signal; otherwise program doesn't know.\n\
9271 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9272 Pass and Stop may be combined.\n\
9274 Multiple signals may be specified. Signal numbers and signal names\n\
9275 may be interspersed with actions, with the actions being performed for\n\
9276 all signals cumulatively specified."));
9277 set_cmd_completer (c, handle_completer);
9280 stop_command = add_cmd ("stop", class_obscure,
9281 not_just_help_class_command, _("\
9282 There is no `stop' command, but you can set a hook on `stop'.\n\
9283 This allows you to set a list of commands to be run each time execution\n\
9284 of the program stops."), &cmdlist);
9286 add_setshow_zuinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\
9287 Set inferior debugging."), _("\
9288 Show inferior debugging."), _("\
9289 When non-zero, inferior specific debugging is enabled."),
9292 &setdebuglist, &showdebuglist);
9294 add_setshow_boolean_cmd ("displaced", class_maintenance,
9295 &debug_displaced, _("\
9296 Set displaced stepping debugging."), _("\
9297 Show displaced stepping debugging."), _("\
9298 When non-zero, displaced stepping specific debugging is enabled."),
9300 show_debug_displaced,
9301 &setdebuglist, &showdebuglist);
9303 add_setshow_boolean_cmd ("non-stop", no_class,
9305 Set whether gdb controls the inferior in non-stop mode."), _("\
9306 Show whether gdb controls the inferior in non-stop mode."), _("\
9307 When debugging a multi-threaded program and this setting is\n\
9308 off (the default, also called all-stop mode), when one thread stops\n\
9309 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9310 all other threads in the program while you interact with the thread of\n\
9311 interest. When you continue or step a thread, you can allow the other\n\
9312 threads to run, or have them remain stopped, but while you inspect any\n\
9313 thread's state, all threads stop.\n\
9315 In non-stop mode, when one thread stops, other threads can continue\n\
9316 to run freely. You'll be able to step each thread independently,\n\
9317 leave it stopped or free to run as needed."),
9323 numsigs = (int) GDB_SIGNAL_LAST;
9324 signal_stop = XNEWVEC (unsigned char, numsigs);
9325 signal_print = XNEWVEC (unsigned char, numsigs);
9326 signal_program = XNEWVEC (unsigned char, numsigs);
9327 signal_catch = XNEWVEC (unsigned char, numsigs);
9328 signal_pass = XNEWVEC (unsigned char, numsigs);
9329 for (i = 0; i < numsigs; i++)
9332 signal_print[i] = 1;
9333 signal_program[i] = 1;
9334 signal_catch[i] = 0;
9337 /* Signals caused by debugger's own actions should not be given to
9338 the program afterwards.
9340 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9341 explicitly specifies that it should be delivered to the target
9342 program. Typically, that would occur when a user is debugging a
9343 target monitor on a simulator: the target monitor sets a
9344 breakpoint; the simulator encounters this breakpoint and halts
9345 the simulation handing control to GDB; GDB, noting that the stop
9346 address doesn't map to any known breakpoint, returns control back
9347 to the simulator; the simulator then delivers the hardware
9348 equivalent of a GDB_SIGNAL_TRAP to the program being
9350 signal_program[GDB_SIGNAL_TRAP] = 0;
9351 signal_program[GDB_SIGNAL_INT] = 0;
9353 /* Signals that are not errors should not normally enter the debugger. */
9354 signal_stop[GDB_SIGNAL_ALRM] = 0;
9355 signal_print[GDB_SIGNAL_ALRM] = 0;
9356 signal_stop[GDB_SIGNAL_VTALRM] = 0;
9357 signal_print[GDB_SIGNAL_VTALRM] = 0;
9358 signal_stop[GDB_SIGNAL_PROF] = 0;
9359 signal_print[GDB_SIGNAL_PROF] = 0;
9360 signal_stop[GDB_SIGNAL_CHLD] = 0;
9361 signal_print[GDB_SIGNAL_CHLD] = 0;
9362 signal_stop[GDB_SIGNAL_IO] = 0;
9363 signal_print[GDB_SIGNAL_IO] = 0;
9364 signal_stop[GDB_SIGNAL_POLL] = 0;
9365 signal_print[GDB_SIGNAL_POLL] = 0;
9366 signal_stop[GDB_SIGNAL_URG] = 0;
9367 signal_print[GDB_SIGNAL_URG] = 0;
9368 signal_stop[GDB_SIGNAL_WINCH] = 0;
9369 signal_print[GDB_SIGNAL_WINCH] = 0;
9370 signal_stop[GDB_SIGNAL_PRIO] = 0;
9371 signal_print[GDB_SIGNAL_PRIO] = 0;
9373 /* These signals are used internally by user-level thread
9374 implementations. (See signal(5) on Solaris.) Like the above
9375 signals, a healthy program receives and handles them as part of
9376 its normal operation. */
9377 signal_stop[GDB_SIGNAL_LWP] = 0;
9378 signal_print[GDB_SIGNAL_LWP] = 0;
9379 signal_stop[GDB_SIGNAL_WAITING] = 0;
9380 signal_print[GDB_SIGNAL_WAITING] = 0;
9381 signal_stop[GDB_SIGNAL_CANCEL] = 0;
9382 signal_print[GDB_SIGNAL_CANCEL] = 0;
9383 signal_stop[GDB_SIGNAL_LIBRT] = 0;
9384 signal_print[GDB_SIGNAL_LIBRT] = 0;
9386 /* Update cached state. */
9387 signal_cache_update (-1);
9389 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support,
9390 &stop_on_solib_events, _("\
9391 Set stopping for shared library events."), _("\
9392 Show stopping for shared library events."), _("\
9393 If nonzero, gdb will give control to the user when the dynamic linker\n\
9394 notifies gdb of shared library events. The most common event of interest\n\
9395 to the user would be loading/unloading of a new library."),
9396 set_stop_on_solib_events,
9397 show_stop_on_solib_events,
9398 &setlist, &showlist);
9400 add_setshow_enum_cmd ("follow-fork-mode", class_run,
9401 follow_fork_mode_kind_names,
9402 &follow_fork_mode_string, _("\
9403 Set debugger response to a program call of fork or vfork."), _("\
9404 Show debugger response to a program call of fork or vfork."), _("\
9405 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9406 parent - the original process is debugged after a fork\n\
9407 child - the new process is debugged after a fork\n\
9408 The unfollowed process will continue to run.\n\
9409 By default, the debugger will follow the parent process."),
9411 show_follow_fork_mode_string,
9412 &setlist, &showlist);
9414 add_setshow_enum_cmd ("follow-exec-mode", class_run,
9415 follow_exec_mode_names,
9416 &follow_exec_mode_string, _("\
9417 Set debugger response to a program call of exec."), _("\
9418 Show debugger response to a program call of exec."), _("\
9419 An exec call replaces the program image of a process.\n\
9421 follow-exec-mode can be:\n\
9423 new - the debugger creates a new inferior and rebinds the process\n\
9424 to this new inferior. The program the process was running before\n\
9425 the exec call can be restarted afterwards by restarting the original\n\
9428 same - the debugger keeps the process bound to the same inferior.\n\
9429 The new executable image replaces the previous executable loaded in\n\
9430 the inferior. Restarting the inferior after the exec call restarts\n\
9431 the executable the process was running after the exec call.\n\
9433 By default, the debugger will use the same inferior."),
9435 show_follow_exec_mode_string,
9436 &setlist, &showlist);
9438 add_setshow_enum_cmd ("scheduler-locking", class_run,
9439 scheduler_enums, &scheduler_mode, _("\
9440 Set mode for locking scheduler during execution."), _("\
9441 Show mode for locking scheduler during execution."), _("\
9442 off == no locking (threads may preempt at any time)\n\
9443 on == full locking (no thread except the current thread may run)\n\
9444 This applies to both normal execution and replay mode.\n\
9445 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9446 In this mode, other threads may run during other commands.\n\
9447 This applies to both normal execution and replay mode.\n\
9448 replay == scheduler locked in replay mode and unlocked during normal execution."),
9449 set_schedlock_func, /* traps on target vector */
9450 show_scheduler_mode,
9451 &setlist, &showlist);
9453 add_setshow_boolean_cmd ("schedule-multiple", class_run, &sched_multi, _("\
9454 Set mode for resuming threads of all processes."), _("\
9455 Show mode for resuming threads of all processes."), _("\
9456 When on, execution commands (such as 'continue' or 'next') resume all\n\
9457 threads of all processes. When off (which is the default), execution\n\
9458 commands only resume the threads of the current process. The set of\n\
9459 threads that are resumed is further refined by the scheduler-locking\n\
9460 mode (see help set scheduler-locking)."),
9462 show_schedule_multiple,
9463 &setlist, &showlist);
9465 add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\
9466 Set mode of the step operation."), _("\
9467 Show mode of the step operation."), _("\
9468 When set, doing a step over a function without debug line information\n\
9469 will stop at the first instruction of that function. Otherwise, the\n\
9470 function is skipped and the step command stops at a different source line."),
9472 show_step_stop_if_no_debug,
9473 &setlist, &showlist);
9475 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run,
9476 &can_use_displaced_stepping, _("\
9477 Set debugger's willingness to use displaced stepping."), _("\
9478 Show debugger's willingness to use displaced stepping."), _("\
9479 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9480 supported by the target architecture. If off, gdb will not use displaced\n\
9481 stepping to step over breakpoints, even if such is supported by the target\n\
9482 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9483 if the target architecture supports it and non-stop mode is active, but will not\n\
9484 use it in all-stop mode (see help set non-stop)."),
9486 show_can_use_displaced_stepping,
9487 &setlist, &showlist);
9489 add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names,
9490 &exec_direction, _("Set direction of execution.\n\
9491 Options are 'forward' or 'reverse'."),
9492 _("Show direction of execution (forward/reverse)."),
9493 _("Tells gdb whether to execute forward or backward."),
9494 set_exec_direction_func, show_exec_direction_func,
9495 &setlist, &showlist);
9497 /* Set/show detach-on-fork: user-settable mode. */
9499 add_setshow_boolean_cmd ("detach-on-fork", class_run, &detach_fork, _("\
9500 Set whether gdb will detach the child of a fork."), _("\
9501 Show whether gdb will detach the child of a fork."), _("\
9502 Tells gdb whether to detach the child of a fork."),
9503 NULL, NULL, &setlist, &showlist);
9505 /* Set/show disable address space randomization mode. */
9507 add_setshow_boolean_cmd ("disable-randomization", class_support,
9508 &disable_randomization, _("\
9509 Set disabling of debuggee's virtual address space randomization."), _("\
9510 Show disabling of debuggee's virtual address space randomization."), _("\
9511 When this mode is on (which is the default), randomization of the virtual\n\
9512 address space is disabled. Standalone programs run with the randomization\n\
9513 enabled by default on some platforms."),
9514 &set_disable_randomization,
9515 &show_disable_randomization,
9516 &setlist, &showlist);
9518 /* ptid initializations */
9519 inferior_ptid = null_ptid;
9520 target_last_wait_ptid = minus_one_ptid;
9522 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed);
9523 observer_attach_thread_stop_requested (infrun_thread_stop_requested);
9524 observer_attach_thread_exit (infrun_thread_thread_exit);
9525 observer_attach_inferior_exit (infrun_inferior_exit);
9527 /* Explicitly create without lookup, since that tries to create a
9528 value with a void typed value, and when we get here, gdbarch
9529 isn't initialized yet. At this point, we're quite sure there
9530 isn't another convenience variable of the same name. */
9531 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs, NULL);
9533 add_setshow_boolean_cmd ("observer", no_class,
9534 &observer_mode_1, _("\
9535 Set whether gdb controls the inferior in observer mode."), _("\
9536 Show whether gdb controls the inferior in observer mode."), _("\
9537 In observer mode, GDB can get data from the inferior, but not\n\
9538 affect its execution. Registers and memory may not be changed,\n\
9539 breakpoints may not be set, and the program cannot be interrupted\n\