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 /* In asynchronous mode, but simulating synchronous execution. */
157 int sync_execution = 0;
159 /* proceed and normal_stop use this to notify the user when the
160 inferior stopped in a different thread than it had been running
163 static ptid_t previous_inferior_ptid;
165 /* If set (default for legacy reasons), when following a fork, GDB
166 will detach from one of the fork branches, child or parent.
167 Exactly which branch is detached depends on 'set follow-fork-mode'
170 static int detach_fork = 1;
172 int debug_displaced = 0;
174 show_debug_displaced (struct ui_file *file, int from_tty,
175 struct cmd_list_element *c, const char *value)
177 fprintf_filtered (file, _("Displace stepping debugging is %s.\n"), value);
180 unsigned int debug_infrun = 0;
182 show_debug_infrun (struct ui_file *file, int from_tty,
183 struct cmd_list_element *c, const char *value)
185 fprintf_filtered (file, _("Inferior debugging is %s.\n"), value);
189 /* Support for disabling address space randomization. */
191 int disable_randomization = 1;
194 show_disable_randomization (struct ui_file *file, int from_tty,
195 struct cmd_list_element *c, const char *value)
197 if (target_supports_disable_randomization ())
198 fprintf_filtered (file,
199 _("Disabling randomization of debuggee's "
200 "virtual address space is %s.\n"),
203 fputs_filtered (_("Disabling randomization of debuggee's "
204 "virtual address space is unsupported on\n"
205 "this platform.\n"), file);
209 set_disable_randomization (char *args, int from_tty,
210 struct cmd_list_element *c)
212 if (!target_supports_disable_randomization ())
213 error (_("Disabling randomization of debuggee's "
214 "virtual address space is unsupported on\n"
218 /* User interface for non-stop mode. */
221 static int non_stop_1 = 0;
224 set_non_stop (char *args, int from_tty,
225 struct cmd_list_element *c)
227 if (target_has_execution)
229 non_stop_1 = non_stop;
230 error (_("Cannot change this setting while the inferior is running."));
233 non_stop = non_stop_1;
237 show_non_stop (struct ui_file *file, int from_tty,
238 struct cmd_list_element *c, const char *value)
240 fprintf_filtered (file,
241 _("Controlling the inferior in non-stop mode is %s.\n"),
245 /* "Observer mode" is somewhat like a more extreme version of
246 non-stop, in which all GDB operations that might affect the
247 target's execution have been disabled. */
249 int observer_mode = 0;
250 static int observer_mode_1 = 0;
253 set_observer_mode (char *args, int from_tty,
254 struct cmd_list_element *c)
256 if (target_has_execution)
258 observer_mode_1 = observer_mode;
259 error (_("Cannot change this setting while the inferior is running."));
262 observer_mode = observer_mode_1;
264 may_write_registers = !observer_mode;
265 may_write_memory = !observer_mode;
266 may_insert_breakpoints = !observer_mode;
267 may_insert_tracepoints = !observer_mode;
268 /* We can insert fast tracepoints in or out of observer mode,
269 but enable them if we're going into this mode. */
271 may_insert_fast_tracepoints = 1;
272 may_stop = !observer_mode;
273 update_target_permissions ();
275 /* Going *into* observer mode we must force non-stop, then
276 going out we leave it that way. */
279 pagination_enabled = 0;
280 non_stop = non_stop_1 = 1;
284 printf_filtered (_("Observer mode is now %s.\n"),
285 (observer_mode ? "on" : "off"));
289 show_observer_mode (struct ui_file *file, int from_tty,
290 struct cmd_list_element *c, const char *value)
292 fprintf_filtered (file, _("Observer mode is %s.\n"), value);
295 /* This updates the value of observer mode based on changes in
296 permissions. Note that we are deliberately ignoring the values of
297 may-write-registers and may-write-memory, since the user may have
298 reason to enable these during a session, for instance to turn on a
299 debugging-related global. */
302 update_observer_mode (void)
306 newval = (!may_insert_breakpoints
307 && !may_insert_tracepoints
308 && may_insert_fast_tracepoints
312 /* Let the user know if things change. */
313 if (newval != observer_mode)
314 printf_filtered (_("Observer mode is now %s.\n"),
315 (newval ? "on" : "off"));
317 observer_mode = observer_mode_1 = newval;
320 /* Tables of how to react to signals; the user sets them. */
322 static unsigned char *signal_stop;
323 static unsigned char *signal_print;
324 static unsigned char *signal_program;
326 /* Table of signals that are registered with "catch signal". A
327 non-zero entry indicates that the signal is caught by some "catch
328 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
330 static unsigned char *signal_catch;
332 /* Table of signals that the target may silently handle.
333 This is automatically determined from the flags above,
334 and simply cached here. */
335 static unsigned char *signal_pass;
337 #define SET_SIGS(nsigs,sigs,flags) \
339 int signum = (nsigs); \
340 while (signum-- > 0) \
341 if ((sigs)[signum]) \
342 (flags)[signum] = 1; \
345 #define UNSET_SIGS(nsigs,sigs,flags) \
347 int signum = (nsigs); \
348 while (signum-- > 0) \
349 if ((sigs)[signum]) \
350 (flags)[signum] = 0; \
353 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
354 this function is to avoid exporting `signal_program'. */
357 update_signals_program_target (void)
359 target_program_signals ((int) GDB_SIGNAL_LAST, signal_program);
362 /* Value to pass to target_resume() to cause all threads to resume. */
364 #define RESUME_ALL minus_one_ptid
366 /* Command list pointer for the "stop" placeholder. */
368 static struct cmd_list_element *stop_command;
370 /* Nonzero if we want to give control to the user when we're notified
371 of shared library events by the dynamic linker. */
372 int stop_on_solib_events;
374 /* Enable or disable optional shared library event breakpoints
375 as appropriate when the above flag is changed. */
378 set_stop_on_solib_events (char *args, int from_tty, struct cmd_list_element *c)
380 update_solib_breakpoints ();
384 show_stop_on_solib_events (struct ui_file *file, int from_tty,
385 struct cmd_list_element *c, const char *value)
387 fprintf_filtered (file, _("Stopping for shared library events is %s.\n"),
391 /* Nonzero after stop if current stack frame should be printed. */
393 static int stop_print_frame;
395 /* This is a cached copy of the pid/waitstatus of the last event
396 returned by target_wait()/deprecated_target_wait_hook(). This
397 information is returned by get_last_target_status(). */
398 static ptid_t target_last_wait_ptid;
399 static struct target_waitstatus target_last_waitstatus;
401 static void context_switch (ptid_t ptid);
403 void init_thread_stepping_state (struct thread_info *tss);
405 static const char follow_fork_mode_child[] = "child";
406 static const char follow_fork_mode_parent[] = "parent";
408 static const char *const follow_fork_mode_kind_names[] = {
409 follow_fork_mode_child,
410 follow_fork_mode_parent,
414 static const char *follow_fork_mode_string = follow_fork_mode_parent;
416 show_follow_fork_mode_string (struct ui_file *file, int from_tty,
417 struct cmd_list_element *c, const char *value)
419 fprintf_filtered (file,
420 _("Debugger response to a program "
421 "call of fork or vfork is \"%s\".\n"),
426 /* Handle changes to the inferior list based on the type of fork,
427 which process is being followed, and whether the other process
428 should be detached. On entry inferior_ptid must be the ptid of
429 the fork parent. At return inferior_ptid is the ptid of the
430 followed inferior. */
433 follow_fork_inferior (int follow_child, int detach_fork)
436 ptid_t parent_ptid, child_ptid;
438 has_vforked = (inferior_thread ()->pending_follow.kind
439 == TARGET_WAITKIND_VFORKED);
440 parent_ptid = inferior_ptid;
441 child_ptid = inferior_thread ()->pending_follow.value.related_pid;
444 && !non_stop /* Non-stop always resumes both branches. */
445 && (!target_is_async_p () || sync_execution)
446 && !(follow_child || detach_fork || sched_multi))
448 /* The parent stays blocked inside the vfork syscall until the
449 child execs or exits. If we don't let the child run, then
450 the parent stays blocked. If we're telling the parent to run
451 in the foreground, the user will not be able to ctrl-c to get
452 back the terminal, effectively hanging the debug session. */
453 fprintf_filtered (gdb_stderr, _("\
454 Can not resume the parent process over vfork in the foreground while\n\
455 holding the child stopped. Try \"set detach-on-fork\" or \
456 \"set schedule-multiple\".\n"));
457 /* FIXME output string > 80 columns. */
463 /* Detach new forked process? */
466 struct cleanup *old_chain;
468 /* Before detaching from the child, remove all breakpoints
469 from it. If we forked, then this has already been taken
470 care of by infrun.c. If we vforked however, any
471 breakpoint inserted in the parent is visible in the
472 child, even those added while stopped in a vfork
473 catchpoint. This will remove the breakpoints from the
474 parent also, but they'll be reinserted below. */
477 /* Keep breakpoints list in sync. */
478 remove_breakpoints_pid (ptid_get_pid (inferior_ptid));
481 if (info_verbose || debug_infrun)
483 /* Ensure that we have a process ptid. */
484 ptid_t process_ptid = pid_to_ptid (ptid_get_pid (child_ptid));
486 target_terminal_ours_for_output ();
487 fprintf_filtered (gdb_stdlog,
488 _("Detaching after %s from child %s.\n"),
489 has_vforked ? "vfork" : "fork",
490 target_pid_to_str (process_ptid));
495 struct inferior *parent_inf, *child_inf;
496 struct cleanup *old_chain;
498 /* Add process to GDB's tables. */
499 child_inf = add_inferior (ptid_get_pid (child_ptid));
501 parent_inf = current_inferior ();
502 child_inf->attach_flag = parent_inf->attach_flag;
503 copy_terminal_info (child_inf, parent_inf);
504 child_inf->gdbarch = parent_inf->gdbarch;
505 copy_inferior_target_desc_info (child_inf, parent_inf);
507 old_chain = save_inferior_ptid ();
508 save_current_program_space ();
510 inferior_ptid = child_ptid;
511 add_thread (inferior_ptid);
512 child_inf->symfile_flags = SYMFILE_NO_READ;
514 /* If this is a vfork child, then the address-space is
515 shared with the parent. */
518 child_inf->pspace = parent_inf->pspace;
519 child_inf->aspace = parent_inf->aspace;
521 /* The parent will be frozen until the child is done
522 with the shared region. Keep track of the
524 child_inf->vfork_parent = parent_inf;
525 child_inf->pending_detach = 0;
526 parent_inf->vfork_child = child_inf;
527 parent_inf->pending_detach = 0;
531 child_inf->aspace = new_address_space ();
532 child_inf->pspace = add_program_space (child_inf->aspace);
533 child_inf->removable = 1;
534 set_current_program_space (child_inf->pspace);
535 clone_program_space (child_inf->pspace, parent_inf->pspace);
537 /* Let the shared library layer (e.g., solib-svr4) learn
538 about this new process, relocate the cloned exec, pull
539 in shared libraries, and install the solib event
540 breakpoint. If a "cloned-VM" event was propagated
541 better throughout the core, this wouldn't be
543 solib_create_inferior_hook (0);
546 do_cleanups (old_chain);
551 struct inferior *parent_inf;
553 parent_inf = current_inferior ();
555 /* If we detached from the child, then we have to be careful
556 to not insert breakpoints in the parent until the child
557 is done with the shared memory region. However, if we're
558 staying attached to the child, then we can and should
559 insert breakpoints, so that we can debug it. A
560 subsequent child exec or exit is enough to know when does
561 the child stops using the parent's address space. */
562 parent_inf->waiting_for_vfork_done = detach_fork;
563 parent_inf->pspace->breakpoints_not_allowed = detach_fork;
568 /* Follow the child. */
569 struct inferior *parent_inf, *child_inf;
570 struct program_space *parent_pspace;
572 if (info_verbose || debug_infrun)
574 target_terminal_ours_for_output ();
575 fprintf_filtered (gdb_stdlog,
576 _("Attaching after %s %s to child %s.\n"),
577 target_pid_to_str (parent_ptid),
578 has_vforked ? "vfork" : "fork",
579 target_pid_to_str (child_ptid));
582 /* Add the new inferior first, so that the target_detach below
583 doesn't unpush the target. */
585 child_inf = add_inferior (ptid_get_pid (child_ptid));
587 parent_inf = current_inferior ();
588 child_inf->attach_flag = parent_inf->attach_flag;
589 copy_terminal_info (child_inf, parent_inf);
590 child_inf->gdbarch = parent_inf->gdbarch;
591 copy_inferior_target_desc_info (child_inf, parent_inf);
593 parent_pspace = parent_inf->pspace;
595 /* If we're vforking, we want to hold on to the parent until the
596 child exits or execs. At child exec or exit time we can
597 remove the old breakpoints from the parent and detach or
598 resume debugging it. Otherwise, detach the parent now; we'll
599 want to reuse it's program/address spaces, but we can't set
600 them to the child before removing breakpoints from the
601 parent, otherwise, the breakpoints module could decide to
602 remove breakpoints from the wrong process (since they'd be
603 assigned to the same address space). */
607 gdb_assert (child_inf->vfork_parent == NULL);
608 gdb_assert (parent_inf->vfork_child == NULL);
609 child_inf->vfork_parent = parent_inf;
610 child_inf->pending_detach = 0;
611 parent_inf->vfork_child = child_inf;
612 parent_inf->pending_detach = detach_fork;
613 parent_inf->waiting_for_vfork_done = 0;
615 else if (detach_fork)
617 if (info_verbose || debug_infrun)
619 /* Ensure that we have a process ptid. */
620 ptid_t process_ptid = pid_to_ptid (ptid_get_pid (child_ptid));
622 target_terminal_ours_for_output ();
623 fprintf_filtered (gdb_stdlog,
624 _("Detaching after fork from "
626 target_pid_to_str (process_ptid));
629 target_detach (NULL, 0);
632 /* Note that the detach above makes PARENT_INF dangling. */
634 /* Add the child thread to the appropriate lists, and switch to
635 this new thread, before cloning the program space, and
636 informing the solib layer about this new process. */
638 inferior_ptid = child_ptid;
639 add_thread (inferior_ptid);
641 /* If this is a vfork child, then the address-space is shared
642 with the parent. If we detached from the parent, then we can
643 reuse the parent's program/address spaces. */
644 if (has_vforked || detach_fork)
646 child_inf->pspace = parent_pspace;
647 child_inf->aspace = child_inf->pspace->aspace;
651 child_inf->aspace = new_address_space ();
652 child_inf->pspace = add_program_space (child_inf->aspace);
653 child_inf->removable = 1;
654 child_inf->symfile_flags = SYMFILE_NO_READ;
655 set_current_program_space (child_inf->pspace);
656 clone_program_space (child_inf->pspace, parent_pspace);
658 /* Let the shared library layer (e.g., solib-svr4) learn
659 about this new process, relocate the cloned exec, pull in
660 shared libraries, and install the solib event breakpoint.
661 If a "cloned-VM" event was propagated better throughout
662 the core, this wouldn't be required. */
663 solib_create_inferior_hook (0);
667 return target_follow_fork (follow_child, detach_fork);
670 /* Tell the target to follow the fork we're stopped at. Returns true
671 if the inferior should be resumed; false, if the target for some
672 reason decided it's best not to resume. */
677 int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
678 int should_resume = 1;
679 struct thread_info *tp;
681 /* Copy user stepping state to the new inferior thread. FIXME: the
682 followed fork child thread should have a copy of most of the
683 parent thread structure's run control related fields, not just these.
684 Initialized to avoid "may be used uninitialized" warnings from gcc. */
685 struct breakpoint *step_resume_breakpoint = NULL;
686 struct breakpoint *exception_resume_breakpoint = NULL;
687 CORE_ADDR step_range_start = 0;
688 CORE_ADDR step_range_end = 0;
689 struct frame_id step_frame_id = { 0 };
690 struct interp *command_interp = NULL;
695 struct target_waitstatus wait_status;
697 /* Get the last target status returned by target_wait(). */
698 get_last_target_status (&wait_ptid, &wait_status);
700 /* If not stopped at a fork event, then there's nothing else to
702 if (wait_status.kind != TARGET_WAITKIND_FORKED
703 && wait_status.kind != TARGET_WAITKIND_VFORKED)
706 /* Check if we switched over from WAIT_PTID, since the event was
708 if (!ptid_equal (wait_ptid, minus_one_ptid)
709 && !ptid_equal (inferior_ptid, wait_ptid))
711 /* We did. Switch back to WAIT_PTID thread, to tell the
712 target to follow it (in either direction). We'll
713 afterwards refuse to resume, and inform the user what
715 switch_to_thread (wait_ptid);
720 tp = inferior_thread ();
722 /* If there were any forks/vforks that were caught and are now to be
723 followed, then do so now. */
724 switch (tp->pending_follow.kind)
726 case TARGET_WAITKIND_FORKED:
727 case TARGET_WAITKIND_VFORKED:
729 ptid_t parent, child;
731 /* If the user did a next/step, etc, over a fork call,
732 preserve the stepping state in the fork child. */
733 if (follow_child && should_resume)
735 step_resume_breakpoint = clone_momentary_breakpoint
736 (tp->control.step_resume_breakpoint);
737 step_range_start = tp->control.step_range_start;
738 step_range_end = tp->control.step_range_end;
739 step_frame_id = tp->control.step_frame_id;
740 exception_resume_breakpoint
741 = clone_momentary_breakpoint (tp->control.exception_resume_breakpoint);
742 command_interp = tp->control.command_interp;
744 /* For now, delete the parent's sr breakpoint, otherwise,
745 parent/child sr breakpoints are considered duplicates,
746 and the child version will not be installed. Remove
747 this when the breakpoints module becomes aware of
748 inferiors and address spaces. */
749 delete_step_resume_breakpoint (tp);
750 tp->control.step_range_start = 0;
751 tp->control.step_range_end = 0;
752 tp->control.step_frame_id = null_frame_id;
753 delete_exception_resume_breakpoint (tp);
754 tp->control.command_interp = NULL;
757 parent = inferior_ptid;
758 child = tp->pending_follow.value.related_pid;
760 /* Set up inferior(s) as specified by the caller, and tell the
761 target to do whatever is necessary to follow either parent
763 if (follow_fork_inferior (follow_child, detach_fork))
765 /* Target refused to follow, or there's some other reason
766 we shouldn't resume. */
771 /* This pending follow fork event is now handled, one way
772 or another. The previous selected thread may be gone
773 from the lists by now, but if it is still around, need
774 to clear the pending follow request. */
775 tp = find_thread_ptid (parent);
777 tp->pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
779 /* This makes sure we don't try to apply the "Switched
780 over from WAIT_PID" logic above. */
781 nullify_last_target_wait_ptid ();
783 /* If we followed the child, switch to it... */
786 switch_to_thread (child);
788 /* ... and preserve the stepping state, in case the
789 user was stepping over the fork call. */
792 tp = inferior_thread ();
793 tp->control.step_resume_breakpoint
794 = step_resume_breakpoint;
795 tp->control.step_range_start = step_range_start;
796 tp->control.step_range_end = step_range_end;
797 tp->control.step_frame_id = step_frame_id;
798 tp->control.exception_resume_breakpoint
799 = exception_resume_breakpoint;
800 tp->control.command_interp = command_interp;
804 /* If we get here, it was because we're trying to
805 resume from a fork catchpoint, but, the user
806 has switched threads away from the thread that
807 forked. In that case, the resume command
808 issued is most likely not applicable to the
809 child, so just warn, and refuse to resume. */
810 warning (_("Not resuming: switched threads "
811 "before following fork child."));
814 /* Reset breakpoints in the child as appropriate. */
815 follow_inferior_reset_breakpoints ();
818 switch_to_thread (parent);
822 case TARGET_WAITKIND_SPURIOUS:
823 /* Nothing to follow. */
826 internal_error (__FILE__, __LINE__,
827 "Unexpected pending_follow.kind %d\n",
828 tp->pending_follow.kind);
832 return should_resume;
836 follow_inferior_reset_breakpoints (void)
838 struct thread_info *tp = inferior_thread ();
840 /* Was there a step_resume breakpoint? (There was if the user
841 did a "next" at the fork() call.) If so, explicitly reset its
842 thread number. Cloned step_resume breakpoints are disabled on
843 creation, so enable it here now that it is associated with the
846 step_resumes are a form of bp that are made to be per-thread.
847 Since we created the step_resume bp when the parent process
848 was being debugged, and now are switching to the child process,
849 from the breakpoint package's viewpoint, that's a switch of
850 "threads". We must update the bp's notion of which thread
851 it is for, or it'll be ignored when it triggers. */
853 if (tp->control.step_resume_breakpoint)
855 breakpoint_re_set_thread (tp->control.step_resume_breakpoint);
856 tp->control.step_resume_breakpoint->loc->enabled = 1;
859 /* Treat exception_resume breakpoints like step_resume breakpoints. */
860 if (tp->control.exception_resume_breakpoint)
862 breakpoint_re_set_thread (tp->control.exception_resume_breakpoint);
863 tp->control.exception_resume_breakpoint->loc->enabled = 1;
866 /* Reinsert all breakpoints in the child. The user may have set
867 breakpoints after catching the fork, in which case those
868 were never set in the child, but only in the parent. This makes
869 sure the inserted breakpoints match the breakpoint list. */
871 breakpoint_re_set ();
872 insert_breakpoints ();
875 /* The child has exited or execed: resume threads of the parent the
876 user wanted to be executing. */
879 proceed_after_vfork_done (struct thread_info *thread,
882 int pid = * (int *) arg;
884 if (ptid_get_pid (thread->ptid) == pid
885 && is_running (thread->ptid)
886 && !is_executing (thread->ptid)
887 && !thread->stop_requested
888 && thread->suspend.stop_signal == GDB_SIGNAL_0)
891 fprintf_unfiltered (gdb_stdlog,
892 "infrun: resuming vfork parent thread %s\n",
893 target_pid_to_str (thread->ptid));
895 switch_to_thread (thread->ptid);
896 clear_proceed_status (0);
897 proceed ((CORE_ADDR) -1, GDB_SIGNAL_DEFAULT);
903 /* Called whenever we notice an exec or exit event, to handle
904 detaching or resuming a vfork parent. */
907 handle_vfork_child_exec_or_exit (int exec)
909 struct inferior *inf = current_inferior ();
911 if (inf->vfork_parent)
913 int resume_parent = -1;
915 /* This exec or exit marks the end of the shared memory region
916 between the parent and the child. If the user wanted to
917 detach from the parent, now is the time. */
919 if (inf->vfork_parent->pending_detach)
921 struct thread_info *tp;
922 struct cleanup *old_chain;
923 struct program_space *pspace;
924 struct address_space *aspace;
926 /* follow-fork child, detach-on-fork on. */
928 inf->vfork_parent->pending_detach = 0;
932 /* If we're handling a child exit, then inferior_ptid
933 points at the inferior's pid, not to a thread. */
934 old_chain = save_inferior_ptid ();
935 save_current_program_space ();
936 save_current_inferior ();
939 old_chain = save_current_space_and_thread ();
941 /* We're letting loose of the parent. */
942 tp = any_live_thread_of_process (inf->vfork_parent->pid);
943 switch_to_thread (tp->ptid);
945 /* We're about to detach from the parent, which implicitly
946 removes breakpoints from its address space. There's a
947 catch here: we want to reuse the spaces for the child,
948 but, parent/child are still sharing the pspace at this
949 point, although the exec in reality makes the kernel give
950 the child a fresh set of new pages. The problem here is
951 that the breakpoints module being unaware of this, would
952 likely chose the child process to write to the parent
953 address space. Swapping the child temporarily away from
954 the spaces has the desired effect. Yes, this is "sort
957 pspace = inf->pspace;
958 aspace = inf->aspace;
962 if (debug_infrun || info_verbose)
964 target_terminal_ours_for_output ();
968 fprintf_filtered (gdb_stdlog,
969 _("Detaching vfork parent process "
970 "%d after child exec.\n"),
971 inf->vfork_parent->pid);
975 fprintf_filtered (gdb_stdlog,
976 _("Detaching vfork parent process "
977 "%d after child exit.\n"),
978 inf->vfork_parent->pid);
982 target_detach (NULL, 0);
985 inf->pspace = pspace;
986 inf->aspace = aspace;
988 do_cleanups (old_chain);
992 /* We're staying attached to the parent, so, really give the
993 child a new address space. */
994 inf->pspace = add_program_space (maybe_new_address_space ());
995 inf->aspace = inf->pspace->aspace;
997 set_current_program_space (inf->pspace);
999 resume_parent = inf->vfork_parent->pid;
1001 /* Break the bonds. */
1002 inf->vfork_parent->vfork_child = NULL;
1006 struct cleanup *old_chain;
1007 struct program_space *pspace;
1009 /* If this is a vfork child exiting, then the pspace and
1010 aspaces were shared with the parent. Since we're
1011 reporting the process exit, we'll be mourning all that is
1012 found in the address space, and switching to null_ptid,
1013 preparing to start a new inferior. But, since we don't
1014 want to clobber the parent's address/program spaces, we
1015 go ahead and create a new one for this exiting
1018 /* Switch to null_ptid, so that clone_program_space doesn't want
1019 to read the selected frame of a dead process. */
1020 old_chain = save_inferior_ptid ();
1021 inferior_ptid = null_ptid;
1023 /* This inferior is dead, so avoid giving the breakpoints
1024 module the option to write through to it (cloning a
1025 program space resets breakpoints). */
1028 pspace = add_program_space (maybe_new_address_space ());
1029 set_current_program_space (pspace);
1031 inf->symfile_flags = SYMFILE_NO_READ;
1032 clone_program_space (pspace, inf->vfork_parent->pspace);
1033 inf->pspace = pspace;
1034 inf->aspace = pspace->aspace;
1036 /* Put back inferior_ptid. We'll continue mourning this
1038 do_cleanups (old_chain);
1040 resume_parent = inf->vfork_parent->pid;
1041 /* Break the bonds. */
1042 inf->vfork_parent->vfork_child = NULL;
1045 inf->vfork_parent = NULL;
1047 gdb_assert (current_program_space == inf->pspace);
1049 if (non_stop && resume_parent != -1)
1051 /* If the user wanted the parent to be running, let it go
1053 struct cleanup *old_chain = make_cleanup_restore_current_thread ();
1056 fprintf_unfiltered (gdb_stdlog,
1057 "infrun: resuming vfork parent process %d\n",
1060 iterate_over_threads (proceed_after_vfork_done, &resume_parent);
1062 do_cleanups (old_chain);
1067 /* Enum strings for "set|show follow-exec-mode". */
1069 static const char follow_exec_mode_new[] = "new";
1070 static const char follow_exec_mode_same[] = "same";
1071 static const char *const follow_exec_mode_names[] =
1073 follow_exec_mode_new,
1074 follow_exec_mode_same,
1078 static const char *follow_exec_mode_string = follow_exec_mode_same;
1080 show_follow_exec_mode_string (struct ui_file *file, int from_tty,
1081 struct cmd_list_element *c, const char *value)
1083 fprintf_filtered (file, _("Follow exec mode is \"%s\".\n"), value);
1086 /* EXECD_PATHNAME is assumed to be non-NULL. */
1089 follow_exec (ptid_t ptid, char *execd_pathname)
1091 struct thread_info *th, *tmp;
1092 struct inferior *inf = current_inferior ();
1093 int pid = ptid_get_pid (ptid);
1094 ptid_t process_ptid;
1096 /* This is an exec event that we actually wish to pay attention to.
1097 Refresh our symbol table to the newly exec'd program, remove any
1098 momentary bp's, etc.
1100 If there are breakpoints, they aren't really inserted now,
1101 since the exec() transformed our inferior into a fresh set
1104 We want to preserve symbolic breakpoints on the list, since
1105 we have hopes that they can be reset after the new a.out's
1106 symbol table is read.
1108 However, any "raw" breakpoints must be removed from the list
1109 (e.g., the solib bp's), since their address is probably invalid
1112 And, we DON'T want to call delete_breakpoints() here, since
1113 that may write the bp's "shadow contents" (the instruction
1114 value that was overwritten witha TRAP instruction). Since
1115 we now have a new a.out, those shadow contents aren't valid. */
1117 mark_breakpoints_out ();
1119 /* The target reports the exec event to the main thread, even if
1120 some other thread does the exec, and even if the main thread was
1121 stopped or already gone. We may still have non-leader threads of
1122 the process on our list. E.g., on targets that don't have thread
1123 exit events (like remote); or on native Linux in non-stop mode if
1124 there were only two threads in the inferior and the non-leader
1125 one is the one that execs (and nothing forces an update of the
1126 thread list up to here). When debugging remotely, it's best to
1127 avoid extra traffic, when possible, so avoid syncing the thread
1128 list with the target, and instead go ahead and delete all threads
1129 of the process but one that reported the event. Note this must
1130 be done before calling update_breakpoints_after_exec, as
1131 otherwise clearing the threads' resources would reference stale
1132 thread breakpoints -- it may have been one of these threads that
1133 stepped across the exec. We could just clear their stepping
1134 states, but as long as we're iterating, might as well delete
1135 them. Deleting them now rather than at the next user-visible
1136 stop provides a nicer sequence of events for user and MI
1138 ALL_THREADS_SAFE (th, tmp)
1139 if (ptid_get_pid (th->ptid) == pid && !ptid_equal (th->ptid, ptid))
1140 delete_thread (th->ptid);
1142 /* We also need to clear any left over stale state for the
1143 leader/event thread. E.g., if there was any step-resume
1144 breakpoint or similar, it's gone now. We cannot truly
1145 step-to-next statement through an exec(). */
1146 th = inferior_thread ();
1147 th->control.step_resume_breakpoint = NULL;
1148 th->control.exception_resume_breakpoint = NULL;
1149 th->control.single_step_breakpoints = NULL;
1150 th->control.step_range_start = 0;
1151 th->control.step_range_end = 0;
1153 /* The user may have had the main thread held stopped in the
1154 previous image (e.g., schedlock on, or non-stop). Release
1156 th->stop_requested = 0;
1158 update_breakpoints_after_exec ();
1160 /* What is this a.out's name? */
1161 process_ptid = pid_to_ptid (pid);
1162 printf_unfiltered (_("%s is executing new program: %s\n"),
1163 target_pid_to_str (process_ptid),
1166 /* We've followed the inferior through an exec. Therefore, the
1167 inferior has essentially been killed & reborn. */
1169 gdb_flush (gdb_stdout);
1171 breakpoint_init_inferior (inf_execd);
1173 if (*gdb_sysroot != '\0')
1175 char *name = exec_file_find (execd_pathname, NULL);
1177 execd_pathname = (char *) alloca (strlen (name) + 1);
1178 strcpy (execd_pathname, name);
1182 /* Reset the shared library package. This ensures that we get a
1183 shlib event when the child reaches "_start", at which point the
1184 dld will have had a chance to initialize the child. */
1185 /* Also, loading a symbol file below may trigger symbol lookups, and
1186 we don't want those to be satisfied by the libraries of the
1187 previous incarnation of this process. */
1188 no_shared_libraries (NULL, 0);
1190 if (follow_exec_mode_string == follow_exec_mode_new)
1192 /* The user wants to keep the old inferior and program spaces
1193 around. Create a new fresh one, and switch to it. */
1195 /* Do exit processing for the original inferior before adding
1196 the new inferior so we don't have two active inferiors with
1197 the same ptid, which can confuse find_inferior_ptid. */
1198 exit_inferior_num_silent (current_inferior ()->num);
1200 inf = add_inferior_with_spaces ();
1202 target_follow_exec (inf, execd_pathname);
1204 set_current_inferior (inf);
1205 set_current_program_space (inf->pspace);
1210 /* The old description may no longer be fit for the new image.
1211 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1212 old description; we'll read a new one below. No need to do
1213 this on "follow-exec-mode new", as the old inferior stays
1214 around (its description is later cleared/refetched on
1216 target_clear_description ();
1219 gdb_assert (current_program_space == inf->pspace);
1221 /* That a.out is now the one to use. */
1222 exec_file_attach (execd_pathname, 0);
1224 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1225 (Position Independent Executable) main symbol file will get applied by
1226 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1227 the breakpoints with the zero displacement. */
1229 symbol_file_add (execd_pathname,
1231 | SYMFILE_MAINLINE | SYMFILE_DEFER_BP_RESET),
1234 if ((inf->symfile_flags & SYMFILE_NO_READ) == 0)
1235 set_initial_language ();
1237 /* If the target can specify a description, read it. Must do this
1238 after flipping to the new executable (because the target supplied
1239 description must be compatible with the executable's
1240 architecture, and the old executable may e.g., be 32-bit, while
1241 the new one 64-bit), and before anything involving memory or
1243 target_find_description ();
1245 solib_create_inferior_hook (0);
1247 jit_inferior_created_hook ();
1249 breakpoint_re_set ();
1251 /* Reinsert all breakpoints. (Those which were symbolic have
1252 been reset to the proper address in the new a.out, thanks
1253 to symbol_file_command...). */
1254 insert_breakpoints ();
1256 /* The next resume of this inferior should bring it to the shlib
1257 startup breakpoints. (If the user had also set bp's on
1258 "main" from the old (parent) process, then they'll auto-
1259 matically get reset there in the new process.). */
1262 /* The queue of threads that need to do a step-over operation to get
1263 past e.g., a breakpoint. What technique is used to step over the
1264 breakpoint/watchpoint does not matter -- all threads end up in the
1265 same queue, to maintain rough temporal order of execution, in order
1266 to avoid starvation, otherwise, we could e.g., find ourselves
1267 constantly stepping the same couple threads past their breakpoints
1268 over and over, if the single-step finish fast enough. */
1269 struct thread_info *step_over_queue_head;
1271 /* Bit flags indicating what the thread needs to step over. */
1273 enum step_over_what_flag
1275 /* Step over a breakpoint. */
1276 STEP_OVER_BREAKPOINT = 1,
1278 /* Step past a non-continuable watchpoint, in order to let the
1279 instruction execute so we can evaluate the watchpoint
1281 STEP_OVER_WATCHPOINT = 2
1283 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag, step_over_what);
1285 /* Info about an instruction that is being stepped over. */
1287 struct step_over_info
1289 /* If we're stepping past a breakpoint, this is the address space
1290 and address of the instruction the breakpoint is set at. We'll
1291 skip inserting all breakpoints here. Valid iff ASPACE is
1293 struct address_space *aspace;
1296 /* The instruction being stepped over triggers a nonsteppable
1297 watchpoint. If true, we'll skip inserting watchpoints. */
1298 int nonsteppable_watchpoint_p;
1301 /* The step-over info of the location that is being stepped over.
1303 Note that with async/breakpoint always-inserted mode, a user might
1304 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1305 being stepped over. As setting a new breakpoint inserts all
1306 breakpoints, we need to make sure the breakpoint being stepped over
1307 isn't inserted then. We do that by only clearing the step-over
1308 info when the step-over is actually finished (or aborted).
1310 Presently GDB can only step over one breakpoint at any given time.
1311 Given threads that can't run code in the same address space as the
1312 breakpoint's can't really miss the breakpoint, GDB could be taught
1313 to step-over at most one breakpoint per address space (so this info
1314 could move to the address space object if/when GDB is extended).
1315 The set of breakpoints being stepped over will normally be much
1316 smaller than the set of all breakpoints, so a flag in the
1317 breakpoint location structure would be wasteful. A separate list
1318 also saves complexity and run-time, as otherwise we'd have to go
1319 through all breakpoint locations clearing their flag whenever we
1320 start a new sequence. Similar considerations weigh against storing
1321 this info in the thread object. Plus, not all step overs actually
1322 have breakpoint locations -- e.g., stepping past a single-step
1323 breakpoint, or stepping to complete a non-continuable
1325 static struct step_over_info step_over_info;
1327 /* Record the address of the breakpoint/instruction we're currently
1331 set_step_over_info (struct address_space *aspace, CORE_ADDR address,
1332 int nonsteppable_watchpoint_p)
1334 step_over_info.aspace = aspace;
1335 step_over_info.address = address;
1336 step_over_info.nonsteppable_watchpoint_p = nonsteppable_watchpoint_p;
1339 /* Called when we're not longer stepping over a breakpoint / an
1340 instruction, so all breakpoints are free to be (re)inserted. */
1343 clear_step_over_info (void)
1346 fprintf_unfiltered (gdb_stdlog,
1347 "infrun: clear_step_over_info\n");
1348 step_over_info.aspace = NULL;
1349 step_over_info.address = 0;
1350 step_over_info.nonsteppable_watchpoint_p = 0;
1356 stepping_past_instruction_at (struct address_space *aspace,
1359 return (step_over_info.aspace != NULL
1360 && breakpoint_address_match (aspace, address,
1361 step_over_info.aspace,
1362 step_over_info.address));
1368 stepping_past_nonsteppable_watchpoint (void)
1370 return step_over_info.nonsteppable_watchpoint_p;
1373 /* Returns true if step-over info is valid. */
1376 step_over_info_valid_p (void)
1378 return (step_over_info.aspace != NULL
1379 || stepping_past_nonsteppable_watchpoint ());
1383 /* Displaced stepping. */
1385 /* In non-stop debugging mode, we must take special care to manage
1386 breakpoints properly; in particular, the traditional strategy for
1387 stepping a thread past a breakpoint it has hit is unsuitable.
1388 'Displaced stepping' is a tactic for stepping one thread past a
1389 breakpoint it has hit while ensuring that other threads running
1390 concurrently will hit the breakpoint as they should.
1392 The traditional way to step a thread T off a breakpoint in a
1393 multi-threaded program in all-stop mode is as follows:
1395 a0) Initially, all threads are stopped, and breakpoints are not
1397 a1) We single-step T, leaving breakpoints uninserted.
1398 a2) We insert breakpoints, and resume all threads.
1400 In non-stop debugging, however, this strategy is unsuitable: we
1401 don't want to have to stop all threads in the system in order to
1402 continue or step T past a breakpoint. Instead, we use displaced
1405 n0) Initially, T is stopped, other threads are running, and
1406 breakpoints are inserted.
1407 n1) We copy the instruction "under" the breakpoint to a separate
1408 location, outside the main code stream, making any adjustments
1409 to the instruction, register, and memory state as directed by
1411 n2) We single-step T over the instruction at its new location.
1412 n3) We adjust the resulting register and memory state as directed
1413 by T's architecture. This includes resetting T's PC to point
1414 back into the main instruction stream.
1417 This approach depends on the following gdbarch methods:
1419 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1420 indicate where to copy the instruction, and how much space must
1421 be reserved there. We use these in step n1.
1423 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1424 address, and makes any necessary adjustments to the instruction,
1425 register contents, and memory. We use this in step n1.
1427 - gdbarch_displaced_step_fixup adjusts registers and memory after
1428 we have successfuly single-stepped the instruction, to yield the
1429 same effect the instruction would have had if we had executed it
1430 at its original address. We use this in step n3.
1432 - gdbarch_displaced_step_free_closure provides cleanup.
1434 The gdbarch_displaced_step_copy_insn and
1435 gdbarch_displaced_step_fixup functions must be written so that
1436 copying an instruction with gdbarch_displaced_step_copy_insn,
1437 single-stepping across the copied instruction, and then applying
1438 gdbarch_displaced_insn_fixup should have the same effects on the
1439 thread's memory and registers as stepping the instruction in place
1440 would have. Exactly which responsibilities fall to the copy and
1441 which fall to the fixup is up to the author of those functions.
1443 See the comments in gdbarch.sh for details.
1445 Note that displaced stepping and software single-step cannot
1446 currently be used in combination, although with some care I think
1447 they could be made to. Software single-step works by placing
1448 breakpoints on all possible subsequent instructions; if the
1449 displaced instruction is a PC-relative jump, those breakpoints
1450 could fall in very strange places --- on pages that aren't
1451 executable, or at addresses that are not proper instruction
1452 boundaries. (We do generally let other threads run while we wait
1453 to hit the software single-step breakpoint, and they might
1454 encounter such a corrupted instruction.) One way to work around
1455 this would be to have gdbarch_displaced_step_copy_insn fully
1456 simulate the effect of PC-relative instructions (and return NULL)
1457 on architectures that use software single-stepping.
1459 In non-stop mode, we can have independent and simultaneous step
1460 requests, so more than one thread may need to simultaneously step
1461 over a breakpoint. The current implementation assumes there is
1462 only one scratch space per process. In this case, we have to
1463 serialize access to the scratch space. If thread A wants to step
1464 over a breakpoint, but we are currently waiting for some other
1465 thread to complete a displaced step, we leave thread A stopped and
1466 place it in the displaced_step_request_queue. Whenever a displaced
1467 step finishes, we pick the next thread in the queue and start a new
1468 displaced step operation on it. See displaced_step_prepare and
1469 displaced_step_fixup for details. */
1471 /* Per-inferior displaced stepping state. */
1472 struct displaced_step_inferior_state
1474 /* Pointer to next in linked list. */
1475 struct displaced_step_inferior_state *next;
1477 /* The process this displaced step state refers to. */
1480 /* True if preparing a displaced step ever failed. If so, we won't
1481 try displaced stepping for this inferior again. */
1484 /* If this is not null_ptid, this is the thread carrying out a
1485 displaced single-step in process PID. This thread's state will
1486 require fixing up once it has completed its step. */
1489 /* The architecture the thread had when we stepped it. */
1490 struct gdbarch *step_gdbarch;
1492 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1493 for post-step cleanup. */
1494 struct displaced_step_closure *step_closure;
1496 /* The address of the original instruction, and the copy we
1498 CORE_ADDR step_original, step_copy;
1500 /* Saved contents of copy area. */
1501 gdb_byte *step_saved_copy;
1504 /* The list of states of processes involved in displaced stepping
1506 static struct displaced_step_inferior_state *displaced_step_inferior_states;
1508 /* Get the displaced stepping state of process PID. */
1510 static struct displaced_step_inferior_state *
1511 get_displaced_stepping_state (int pid)
1513 struct displaced_step_inferior_state *state;
1515 for (state = displaced_step_inferior_states;
1517 state = state->next)
1518 if (state->pid == pid)
1524 /* Returns true if any inferior has a thread doing a displaced
1528 displaced_step_in_progress_any_inferior (void)
1530 struct displaced_step_inferior_state *state;
1532 for (state = displaced_step_inferior_states;
1534 state = state->next)
1535 if (!ptid_equal (state->step_ptid, null_ptid))
1541 /* Return true if thread represented by PTID is doing a displaced
1545 displaced_step_in_progress_thread (ptid_t ptid)
1547 struct displaced_step_inferior_state *displaced;
1549 gdb_assert (!ptid_equal (ptid, null_ptid));
1551 displaced = get_displaced_stepping_state (ptid_get_pid (ptid));
1553 return (displaced != NULL && ptid_equal (displaced->step_ptid, ptid));
1556 /* Return true if process PID has a thread doing a displaced step. */
1559 displaced_step_in_progress (int pid)
1561 struct displaced_step_inferior_state *displaced;
1563 displaced = get_displaced_stepping_state (pid);
1564 if (displaced != NULL && !ptid_equal (displaced->step_ptid, null_ptid))
1570 /* Add a new displaced stepping state for process PID to the displaced
1571 stepping state list, or return a pointer to an already existing
1572 entry, if it already exists. Never returns NULL. */
1574 static struct displaced_step_inferior_state *
1575 add_displaced_stepping_state (int pid)
1577 struct displaced_step_inferior_state *state;
1579 for (state = displaced_step_inferior_states;
1581 state = state->next)
1582 if (state->pid == pid)
1585 state = XCNEW (struct displaced_step_inferior_state);
1587 state->next = displaced_step_inferior_states;
1588 displaced_step_inferior_states = state;
1593 /* If inferior is in displaced stepping, and ADDR equals to starting address
1594 of copy area, return corresponding displaced_step_closure. Otherwise,
1597 struct displaced_step_closure*
1598 get_displaced_step_closure_by_addr (CORE_ADDR addr)
1600 struct displaced_step_inferior_state *displaced
1601 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
1603 /* If checking the mode of displaced instruction in copy area. */
1604 if (displaced && !ptid_equal (displaced->step_ptid, null_ptid)
1605 && (displaced->step_copy == addr))
1606 return displaced->step_closure;
1611 /* Remove the displaced stepping state of process PID. */
1614 remove_displaced_stepping_state (int pid)
1616 struct displaced_step_inferior_state *it, **prev_next_p;
1618 gdb_assert (pid != 0);
1620 it = displaced_step_inferior_states;
1621 prev_next_p = &displaced_step_inferior_states;
1626 *prev_next_p = it->next;
1631 prev_next_p = &it->next;
1637 infrun_inferior_exit (struct inferior *inf)
1639 remove_displaced_stepping_state (inf->pid);
1642 /* If ON, and the architecture supports it, GDB will use displaced
1643 stepping to step over breakpoints. If OFF, or if the architecture
1644 doesn't support it, GDB will instead use the traditional
1645 hold-and-step approach. If AUTO (which is the default), GDB will
1646 decide which technique to use to step over breakpoints depending on
1647 which of all-stop or non-stop mode is active --- displaced stepping
1648 in non-stop mode; hold-and-step in all-stop mode. */
1650 static enum auto_boolean can_use_displaced_stepping = AUTO_BOOLEAN_AUTO;
1653 show_can_use_displaced_stepping (struct ui_file *file, int from_tty,
1654 struct cmd_list_element *c,
1657 if (can_use_displaced_stepping == AUTO_BOOLEAN_AUTO)
1658 fprintf_filtered (file,
1659 _("Debugger's willingness to use displaced stepping "
1660 "to step over breakpoints is %s (currently %s).\n"),
1661 value, target_is_non_stop_p () ? "on" : "off");
1663 fprintf_filtered (file,
1664 _("Debugger's willingness to use displaced stepping "
1665 "to step over breakpoints is %s.\n"), value);
1668 /* Return non-zero if displaced stepping can/should be used to step
1669 over breakpoints of thread TP. */
1672 use_displaced_stepping (struct thread_info *tp)
1674 struct regcache *regcache = get_thread_regcache (tp->ptid);
1675 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1676 struct displaced_step_inferior_state *displaced_state;
1678 displaced_state = get_displaced_stepping_state (ptid_get_pid (tp->ptid));
1680 return (((can_use_displaced_stepping == AUTO_BOOLEAN_AUTO
1681 && target_is_non_stop_p ())
1682 || can_use_displaced_stepping == AUTO_BOOLEAN_TRUE)
1683 && gdbarch_displaced_step_copy_insn_p (gdbarch)
1684 && find_record_target () == NULL
1685 && (displaced_state == NULL
1686 || !displaced_state->failed_before));
1689 /* Clean out any stray displaced stepping state. */
1691 displaced_step_clear (struct displaced_step_inferior_state *displaced)
1693 /* Indicate that there is no cleanup pending. */
1694 displaced->step_ptid = null_ptid;
1696 if (displaced->step_closure)
1698 gdbarch_displaced_step_free_closure (displaced->step_gdbarch,
1699 displaced->step_closure);
1700 displaced->step_closure = NULL;
1705 displaced_step_clear_cleanup (void *arg)
1707 struct displaced_step_inferior_state *state
1708 = (struct displaced_step_inferior_state *) arg;
1710 displaced_step_clear (state);
1713 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1715 displaced_step_dump_bytes (struct ui_file *file,
1716 const gdb_byte *buf,
1721 for (i = 0; i < len; i++)
1722 fprintf_unfiltered (file, "%02x ", buf[i]);
1723 fputs_unfiltered ("\n", file);
1726 /* Prepare to single-step, using displaced stepping.
1728 Note that we cannot use displaced stepping when we have a signal to
1729 deliver. If we have a signal to deliver and an instruction to step
1730 over, then after the step, there will be no indication from the
1731 target whether the thread entered a signal handler or ignored the
1732 signal and stepped over the instruction successfully --- both cases
1733 result in a simple SIGTRAP. In the first case we mustn't do a
1734 fixup, and in the second case we must --- but we can't tell which.
1735 Comments in the code for 'random signals' in handle_inferior_event
1736 explain how we handle this case instead.
1738 Returns 1 if preparing was successful -- this thread is going to be
1739 stepped now; 0 if displaced stepping this thread got queued; or -1
1740 if this instruction can't be displaced stepped. */
1743 displaced_step_prepare_throw (ptid_t ptid)
1745 struct cleanup *old_cleanups, *ignore_cleanups;
1746 struct thread_info *tp = find_thread_ptid (ptid);
1747 struct regcache *regcache = get_thread_regcache (ptid);
1748 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1749 struct address_space *aspace = get_regcache_aspace (regcache);
1750 CORE_ADDR original, copy;
1752 struct displaced_step_closure *closure;
1753 struct displaced_step_inferior_state *displaced;
1756 /* We should never reach this function if the architecture does not
1757 support displaced stepping. */
1758 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch));
1760 /* Nor if the thread isn't meant to step over a breakpoint. */
1761 gdb_assert (tp->control.trap_expected);
1763 /* Disable range stepping while executing in the scratch pad. We
1764 want a single-step even if executing the displaced instruction in
1765 the scratch buffer lands within the stepping range (e.g., a
1767 tp->control.may_range_step = 0;
1769 /* We have to displaced step one thread at a time, as we only have
1770 access to a single scratch space per inferior. */
1772 displaced = add_displaced_stepping_state (ptid_get_pid (ptid));
1774 if (!ptid_equal (displaced->step_ptid, null_ptid))
1776 /* Already waiting for a displaced step to finish. Defer this
1777 request and place in queue. */
1779 if (debug_displaced)
1780 fprintf_unfiltered (gdb_stdlog,
1781 "displaced: deferring step of %s\n",
1782 target_pid_to_str (ptid));
1784 thread_step_over_chain_enqueue (tp);
1789 if (debug_displaced)
1790 fprintf_unfiltered (gdb_stdlog,
1791 "displaced: stepping %s now\n",
1792 target_pid_to_str (ptid));
1795 displaced_step_clear (displaced);
1797 old_cleanups = save_inferior_ptid ();
1798 inferior_ptid = ptid;
1800 original = regcache_read_pc (regcache);
1802 copy = gdbarch_displaced_step_location (gdbarch);
1803 len = gdbarch_max_insn_length (gdbarch);
1805 if (breakpoint_in_range_p (aspace, copy, len))
1807 /* There's a breakpoint set in the scratch pad location range
1808 (which is usually around the entry point). We'd either
1809 install it before resuming, which would overwrite/corrupt the
1810 scratch pad, or if it was already inserted, this displaced
1811 step would overwrite it. The latter is OK in the sense that
1812 we already assume that no thread is going to execute the code
1813 in the scratch pad range (after initial startup) anyway, but
1814 the former is unacceptable. Simply punt and fallback to
1815 stepping over this breakpoint in-line. */
1816 if (debug_displaced)
1818 fprintf_unfiltered (gdb_stdlog,
1819 "displaced: breakpoint set in scratch pad. "
1820 "Stepping over breakpoint in-line instead.\n");
1823 do_cleanups (old_cleanups);
1827 /* Save the original contents of the copy area. */
1828 displaced->step_saved_copy = (gdb_byte *) xmalloc (len);
1829 ignore_cleanups = make_cleanup (free_current_contents,
1830 &displaced->step_saved_copy);
1831 status = target_read_memory (copy, displaced->step_saved_copy, len);
1833 throw_error (MEMORY_ERROR,
1834 _("Error accessing memory address %s (%s) for "
1835 "displaced-stepping scratch space."),
1836 paddress (gdbarch, copy), safe_strerror (status));
1837 if (debug_displaced)
1839 fprintf_unfiltered (gdb_stdlog, "displaced: saved %s: ",
1840 paddress (gdbarch, copy));
1841 displaced_step_dump_bytes (gdb_stdlog,
1842 displaced->step_saved_copy,
1846 closure = gdbarch_displaced_step_copy_insn (gdbarch,
1847 original, copy, regcache);
1848 if (closure == NULL)
1850 /* The architecture doesn't know how or want to displaced step
1851 this instruction or instruction sequence. Fallback to
1852 stepping over the breakpoint in-line. */
1853 do_cleanups (old_cleanups);
1857 /* Save the information we need to fix things up if the step
1859 displaced->step_ptid = ptid;
1860 displaced->step_gdbarch = gdbarch;
1861 displaced->step_closure = closure;
1862 displaced->step_original = original;
1863 displaced->step_copy = copy;
1865 make_cleanup (displaced_step_clear_cleanup, displaced);
1867 /* Resume execution at the copy. */
1868 regcache_write_pc (regcache, copy);
1870 discard_cleanups (ignore_cleanups);
1872 do_cleanups (old_cleanups);
1874 if (debug_displaced)
1875 fprintf_unfiltered (gdb_stdlog, "displaced: displaced pc to %s\n",
1876 paddress (gdbarch, copy));
1881 /* Wrapper for displaced_step_prepare_throw that disabled further
1882 attempts at displaced stepping if we get a memory error. */
1885 displaced_step_prepare (ptid_t ptid)
1891 prepared = displaced_step_prepare_throw (ptid);
1893 CATCH (ex, RETURN_MASK_ERROR)
1895 struct displaced_step_inferior_state *displaced_state;
1897 if (ex.error != MEMORY_ERROR)
1898 throw_exception (ex);
1902 fprintf_unfiltered (gdb_stdlog,
1903 "infrun: disabling displaced stepping: %s\n",
1907 /* Be verbose if "set displaced-stepping" is "on", silent if
1909 if (can_use_displaced_stepping == AUTO_BOOLEAN_TRUE)
1911 warning (_("disabling displaced stepping: %s"),
1915 /* Disable further displaced stepping attempts. */
1917 = get_displaced_stepping_state (ptid_get_pid (ptid));
1918 displaced_state->failed_before = 1;
1926 write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr,
1927 const gdb_byte *myaddr, int len)
1929 struct cleanup *ptid_cleanup = save_inferior_ptid ();
1931 inferior_ptid = ptid;
1932 write_memory (memaddr, myaddr, len);
1933 do_cleanups (ptid_cleanup);
1936 /* Restore the contents of the copy area for thread PTID. */
1939 displaced_step_restore (struct displaced_step_inferior_state *displaced,
1942 ULONGEST len = gdbarch_max_insn_length (displaced->step_gdbarch);
1944 write_memory_ptid (ptid, displaced->step_copy,
1945 displaced->step_saved_copy, len);
1946 if (debug_displaced)
1947 fprintf_unfiltered (gdb_stdlog, "displaced: restored %s %s\n",
1948 target_pid_to_str (ptid),
1949 paddress (displaced->step_gdbarch,
1950 displaced->step_copy));
1953 /* If we displaced stepped an instruction successfully, adjust
1954 registers and memory to yield the same effect the instruction would
1955 have had if we had executed it at its original address, and return
1956 1. If the instruction didn't complete, relocate the PC and return
1957 -1. If the thread wasn't displaced stepping, return 0. */
1960 displaced_step_fixup (ptid_t event_ptid, enum gdb_signal signal)
1962 struct cleanup *old_cleanups;
1963 struct displaced_step_inferior_state *displaced
1964 = get_displaced_stepping_state (ptid_get_pid (event_ptid));
1967 /* Was any thread of this process doing a displaced step? */
1968 if (displaced == NULL)
1971 /* Was this event for the pid we displaced? */
1972 if (ptid_equal (displaced->step_ptid, null_ptid)
1973 || ! ptid_equal (displaced->step_ptid, event_ptid))
1976 old_cleanups = make_cleanup (displaced_step_clear_cleanup, displaced);
1978 displaced_step_restore (displaced, displaced->step_ptid);
1980 /* Fixup may need to read memory/registers. Switch to the thread
1981 that we're fixing up. Also, target_stopped_by_watchpoint checks
1982 the current thread. */
1983 switch_to_thread (event_ptid);
1985 /* Did the instruction complete successfully? */
1986 if (signal == GDB_SIGNAL_TRAP
1987 && !(target_stopped_by_watchpoint ()
1988 && (gdbarch_have_nonsteppable_watchpoint (displaced->step_gdbarch)
1989 || target_have_steppable_watchpoint)))
1991 /* Fix up the resulting state. */
1992 gdbarch_displaced_step_fixup (displaced->step_gdbarch,
1993 displaced->step_closure,
1994 displaced->step_original,
1995 displaced->step_copy,
1996 get_thread_regcache (displaced->step_ptid));
2001 /* Since the instruction didn't complete, all we can do is
2003 struct regcache *regcache = get_thread_regcache (event_ptid);
2004 CORE_ADDR pc = regcache_read_pc (regcache);
2006 pc = displaced->step_original + (pc - displaced->step_copy);
2007 regcache_write_pc (regcache, pc);
2011 do_cleanups (old_cleanups);
2013 displaced->step_ptid = null_ptid;
2018 /* Data to be passed around while handling an event. This data is
2019 discarded between events. */
2020 struct execution_control_state
2023 /* The thread that got the event, if this was a thread event; NULL
2025 struct thread_info *event_thread;
2027 struct target_waitstatus ws;
2028 int stop_func_filled_in;
2029 CORE_ADDR stop_func_start;
2030 CORE_ADDR stop_func_end;
2031 const char *stop_func_name;
2034 /* True if the event thread hit the single-step breakpoint of
2035 another thread. Thus the event doesn't cause a stop, the thread
2036 needs to be single-stepped past the single-step breakpoint before
2037 we can switch back to the original stepping thread. */
2038 int hit_singlestep_breakpoint;
2041 /* Clear ECS and set it to point at TP. */
2044 reset_ecs (struct execution_control_state *ecs, struct thread_info *tp)
2046 memset (ecs, 0, sizeof (*ecs));
2047 ecs->event_thread = tp;
2048 ecs->ptid = tp->ptid;
2051 static void keep_going_pass_signal (struct execution_control_state *ecs);
2052 static void prepare_to_wait (struct execution_control_state *ecs);
2053 static int keep_going_stepped_thread (struct thread_info *tp);
2054 static step_over_what thread_still_needs_step_over (struct thread_info *tp);
2056 /* Are there any pending step-over requests? If so, run all we can
2057 now and return true. Otherwise, return false. */
2060 start_step_over (void)
2062 struct thread_info *tp, *next;
2064 /* Don't start a new step-over if we already have an in-line
2065 step-over operation ongoing. */
2066 if (step_over_info_valid_p ())
2069 for (tp = step_over_queue_head; tp != NULL; tp = next)
2071 struct execution_control_state ecss;
2072 struct execution_control_state *ecs = &ecss;
2073 step_over_what step_what;
2074 int must_be_in_line;
2076 next = thread_step_over_chain_next (tp);
2078 /* If this inferior already has a displaced step in process,
2079 don't start a new one. */
2080 if (displaced_step_in_progress (ptid_get_pid (tp->ptid)))
2083 step_what = thread_still_needs_step_over (tp);
2084 must_be_in_line = ((step_what & STEP_OVER_WATCHPOINT)
2085 || ((step_what & STEP_OVER_BREAKPOINT)
2086 && !use_displaced_stepping (tp)));
2088 /* We currently stop all threads of all processes to step-over
2089 in-line. If we need to start a new in-line step-over, let
2090 any pending displaced steps finish first. */
2091 if (must_be_in_line && displaced_step_in_progress_any_inferior ())
2094 thread_step_over_chain_remove (tp);
2096 if (step_over_queue_head == NULL)
2099 fprintf_unfiltered (gdb_stdlog,
2100 "infrun: step-over queue now empty\n");
2103 if (tp->control.trap_expected
2107 internal_error (__FILE__, __LINE__,
2108 "[%s] has inconsistent state: "
2109 "trap_expected=%d, resumed=%d, executing=%d\n",
2110 target_pid_to_str (tp->ptid),
2111 tp->control.trap_expected,
2117 fprintf_unfiltered (gdb_stdlog,
2118 "infrun: resuming [%s] for step-over\n",
2119 target_pid_to_str (tp->ptid));
2121 /* keep_going_pass_signal skips the step-over if the breakpoint
2122 is no longer inserted. In all-stop, we want to keep looking
2123 for a thread that needs a step-over instead of resuming TP,
2124 because we wouldn't be able to resume anything else until the
2125 target stops again. In non-stop, the resume always resumes
2126 only TP, so it's OK to let the thread resume freely. */
2127 if (!target_is_non_stop_p () && !step_what)
2130 switch_to_thread (tp->ptid);
2131 reset_ecs (ecs, tp);
2132 keep_going_pass_signal (ecs);
2134 if (!ecs->wait_some_more)
2135 error (_("Command aborted."));
2137 gdb_assert (tp->resumed);
2139 /* If we started a new in-line step-over, we're done. */
2140 if (step_over_info_valid_p ())
2142 gdb_assert (tp->control.trap_expected);
2146 if (!target_is_non_stop_p ())
2148 /* On all-stop, shouldn't have resumed unless we needed a
2150 gdb_assert (tp->control.trap_expected
2151 || tp->step_after_step_resume_breakpoint);
2153 /* With remote targets (at least), in all-stop, we can't
2154 issue any further remote commands until the program stops
2159 /* Either the thread no longer needed a step-over, or a new
2160 displaced stepping sequence started. Even in the latter
2161 case, continue looking. Maybe we can also start another
2162 displaced step on a thread of other process. */
2168 /* Update global variables holding ptids to hold NEW_PTID if they were
2169 holding OLD_PTID. */
2171 infrun_thread_ptid_changed (ptid_t old_ptid, ptid_t new_ptid)
2173 struct displaced_step_request *it;
2174 struct displaced_step_inferior_state *displaced;
2176 if (ptid_equal (inferior_ptid, old_ptid))
2177 inferior_ptid = new_ptid;
2179 for (displaced = displaced_step_inferior_states;
2181 displaced = displaced->next)
2183 if (ptid_equal (displaced->step_ptid, old_ptid))
2184 displaced->step_ptid = new_ptid;
2191 /* Things to clean up if we QUIT out of resume (). */
2193 resume_cleanups (void *ignore)
2195 if (!ptid_equal (inferior_ptid, null_ptid))
2196 delete_single_step_breakpoints (inferior_thread ());
2201 static const char schedlock_off[] = "off";
2202 static const char schedlock_on[] = "on";
2203 static const char schedlock_step[] = "step";
2204 static const char schedlock_replay[] = "replay";
2205 static const char *const scheduler_enums[] = {
2212 static const char *scheduler_mode = schedlock_replay;
2214 show_scheduler_mode (struct ui_file *file, int from_tty,
2215 struct cmd_list_element *c, const char *value)
2217 fprintf_filtered (file,
2218 _("Mode for locking scheduler "
2219 "during execution is \"%s\".\n"),
2224 set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
2226 if (!target_can_lock_scheduler)
2228 scheduler_mode = schedlock_off;
2229 error (_("Target '%s' cannot support this command."), target_shortname);
2233 /* True if execution commands resume all threads of all processes by
2234 default; otherwise, resume only threads of the current inferior
2236 int sched_multi = 0;
2238 /* Try to setup for software single stepping over the specified location.
2239 Return 1 if target_resume() should use hardware single step.
2241 GDBARCH the current gdbarch.
2242 PC the location to step over. */
2245 maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc)
2249 if (execution_direction == EXEC_FORWARD
2250 && gdbarch_software_single_step_p (gdbarch)
2251 && gdbarch_software_single_step (gdbarch, get_current_frame ()))
2261 user_visible_resume_ptid (int step)
2267 /* With non-stop mode on, threads are always handled
2269 resume_ptid = inferior_ptid;
2271 else if ((scheduler_mode == schedlock_on)
2272 || (scheduler_mode == schedlock_step && step))
2274 /* User-settable 'scheduler' mode requires solo thread
2276 resume_ptid = inferior_ptid;
2278 else if ((scheduler_mode == schedlock_replay)
2279 && target_record_will_replay (minus_one_ptid, execution_direction))
2281 /* User-settable 'scheduler' mode requires solo thread resume in replay
2283 resume_ptid = inferior_ptid;
2285 else if (!sched_multi && target_supports_multi_process ())
2287 /* Resume all threads of the current process (and none of other
2289 resume_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
2293 /* Resume all threads of all processes. */
2294 resume_ptid = RESUME_ALL;
2300 /* Return a ptid representing the set of threads that we will resume,
2301 in the perspective of the target, assuming run control handling
2302 does not require leaving some threads stopped (e.g., stepping past
2303 breakpoint). USER_STEP indicates whether we're about to start the
2304 target for a stepping command. */
2307 internal_resume_ptid (int user_step)
2309 /* In non-stop, we always control threads individually. Note that
2310 the target may always work in non-stop mode even with "set
2311 non-stop off", in which case user_visible_resume_ptid could
2312 return a wildcard ptid. */
2313 if (target_is_non_stop_p ())
2314 return inferior_ptid;
2316 return user_visible_resume_ptid (user_step);
2319 /* Wrapper for target_resume, that handles infrun-specific
2323 do_target_resume (ptid_t resume_ptid, int step, enum gdb_signal sig)
2325 struct thread_info *tp = inferior_thread ();
2327 /* Install inferior's terminal modes. */
2328 target_terminal_inferior ();
2330 /* Avoid confusing the next resume, if the next stop/resume
2331 happens to apply to another thread. */
2332 tp->suspend.stop_signal = GDB_SIGNAL_0;
2334 /* Advise target which signals may be handled silently.
2336 If we have removed breakpoints because we are stepping over one
2337 in-line (in any thread), we need to receive all signals to avoid
2338 accidentally skipping a breakpoint during execution of a signal
2341 Likewise if we're displaced stepping, otherwise a trap for a
2342 breakpoint in a signal handler might be confused with the
2343 displaced step finishing. We don't make the displaced_step_fixup
2344 step distinguish the cases instead, because:
2346 - a backtrace while stopped in the signal handler would show the
2347 scratch pad as frame older than the signal handler, instead of
2348 the real mainline code.
2350 - when the thread is later resumed, the signal handler would
2351 return to the scratch pad area, which would no longer be
2353 if (step_over_info_valid_p ()
2354 || displaced_step_in_progress (ptid_get_pid (tp->ptid)))
2355 target_pass_signals (0, NULL);
2357 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
2359 target_resume (resume_ptid, step, sig);
2362 /* Resume the inferior, but allow a QUIT. This is useful if the user
2363 wants to interrupt some lengthy single-stepping operation
2364 (for child processes, the SIGINT goes to the inferior, and so
2365 we get a SIGINT random_signal, but for remote debugging and perhaps
2366 other targets, that's not true).
2368 SIG is the signal to give the inferior (zero for none). */
2370 resume (enum gdb_signal sig)
2372 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
2373 struct regcache *regcache = get_current_regcache ();
2374 struct gdbarch *gdbarch = get_regcache_arch (regcache);
2375 struct thread_info *tp = inferior_thread ();
2376 CORE_ADDR pc = regcache_read_pc (regcache);
2377 struct address_space *aspace = get_regcache_aspace (regcache);
2379 /* This represents the user's step vs continue request. When
2380 deciding whether "set scheduler-locking step" applies, it's the
2381 user's intention that counts. */
2382 const int user_step = tp->control.stepping_command;
2383 /* This represents what we'll actually request the target to do.
2384 This can decay from a step to a continue, if e.g., we need to
2385 implement single-stepping with breakpoints (software
2389 gdb_assert (!thread_is_in_step_over_chain (tp));
2393 if (tp->suspend.waitstatus_pending_p)
2399 statstr = target_waitstatus_to_string (&tp->suspend.waitstatus);
2400 fprintf_unfiltered (gdb_stdlog,
2401 "infrun: resume: thread %s has pending wait status %s "
2402 "(currently_stepping=%d).\n",
2403 target_pid_to_str (tp->ptid), statstr,
2404 currently_stepping (tp));
2410 /* FIXME: What should we do if we are supposed to resume this
2411 thread with a signal? Maybe we should maintain a queue of
2412 pending signals to deliver. */
2413 if (sig != GDB_SIGNAL_0)
2415 warning (_("Couldn't deliver signal %s to %s."),
2416 gdb_signal_to_name (sig), target_pid_to_str (tp->ptid));
2419 tp->suspend.stop_signal = GDB_SIGNAL_0;
2420 discard_cleanups (old_cleanups);
2422 if (target_can_async_p ())
2427 tp->stepped_breakpoint = 0;
2429 /* Depends on stepped_breakpoint. */
2430 step = currently_stepping (tp);
2432 if (current_inferior ()->waiting_for_vfork_done)
2434 /* Don't try to single-step a vfork parent that is waiting for
2435 the child to get out of the shared memory region (by exec'ing
2436 or exiting). This is particularly important on software
2437 single-step archs, as the child process would trip on the
2438 software single step breakpoint inserted for the parent
2439 process. Since the parent will not actually execute any
2440 instruction until the child is out of the shared region (such
2441 are vfork's semantics), it is safe to simply continue it.
2442 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2443 the parent, and tell it to `keep_going', which automatically
2444 re-sets it stepping. */
2446 fprintf_unfiltered (gdb_stdlog,
2447 "infrun: resume : clear step\n");
2452 fprintf_unfiltered (gdb_stdlog,
2453 "infrun: resume (step=%d, signal=%s), "
2454 "trap_expected=%d, current thread [%s] at %s\n",
2455 step, gdb_signal_to_symbol_string (sig),
2456 tp->control.trap_expected,
2457 target_pid_to_str (inferior_ptid),
2458 paddress (gdbarch, pc));
2460 /* Normally, by the time we reach `resume', the breakpoints are either
2461 removed or inserted, as appropriate. The exception is if we're sitting
2462 at a permanent breakpoint; we need to step over it, but permanent
2463 breakpoints can't be removed. So we have to test for it here. */
2464 if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here)
2466 if (sig != GDB_SIGNAL_0)
2468 /* We have a signal to pass to the inferior. The resume
2469 may, or may not take us to the signal handler. If this
2470 is a step, we'll need to stop in the signal handler, if
2471 there's one, (if the target supports stepping into
2472 handlers), or in the next mainline instruction, if
2473 there's no handler. If this is a continue, we need to be
2474 sure to run the handler with all breakpoints inserted.
2475 In all cases, set a breakpoint at the current address
2476 (where the handler returns to), and once that breakpoint
2477 is hit, resume skipping the permanent breakpoint. If
2478 that breakpoint isn't hit, then we've stepped into the
2479 signal handler (or hit some other event). We'll delete
2480 the step-resume breakpoint then. */
2483 fprintf_unfiltered (gdb_stdlog,
2484 "infrun: resume: skipping permanent breakpoint, "
2485 "deliver signal first\n");
2487 clear_step_over_info ();
2488 tp->control.trap_expected = 0;
2490 if (tp->control.step_resume_breakpoint == NULL)
2492 /* Set a "high-priority" step-resume, as we don't want
2493 user breakpoints at PC to trigger (again) when this
2495 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2496 gdb_assert (tp->control.step_resume_breakpoint->loc->permanent);
2498 tp->step_after_step_resume_breakpoint = step;
2501 insert_breakpoints ();
2505 /* There's no signal to pass, we can go ahead and skip the
2506 permanent breakpoint manually. */
2508 fprintf_unfiltered (gdb_stdlog,
2509 "infrun: resume: skipping permanent breakpoint\n");
2510 gdbarch_skip_permanent_breakpoint (gdbarch, regcache);
2511 /* Update pc to reflect the new address from which we will
2512 execute instructions. */
2513 pc = regcache_read_pc (regcache);
2517 /* We've already advanced the PC, so the stepping part
2518 is done. Now we need to arrange for a trap to be
2519 reported to handle_inferior_event. Set a breakpoint
2520 at the current PC, and run to it. Don't update
2521 prev_pc, because if we end in
2522 switch_back_to_stepped_thread, we want the "expected
2523 thread advanced also" branch to be taken. IOW, we
2524 don't want this thread to step further from PC
2526 gdb_assert (!step_over_info_valid_p ());
2527 insert_single_step_breakpoint (gdbarch, aspace, pc);
2528 insert_breakpoints ();
2530 resume_ptid = internal_resume_ptid (user_step);
2531 do_target_resume (resume_ptid, 0, GDB_SIGNAL_0);
2532 discard_cleanups (old_cleanups);
2539 /* If we have a breakpoint to step over, make sure to do a single
2540 step only. Same if we have software watchpoints. */
2541 if (tp->control.trap_expected || bpstat_should_step ())
2542 tp->control.may_range_step = 0;
2544 /* If enabled, step over breakpoints by executing a copy of the
2545 instruction at a different address.
2547 We can't use displaced stepping when we have a signal to deliver;
2548 the comments for displaced_step_prepare explain why. The
2549 comments in the handle_inferior event for dealing with 'random
2550 signals' explain what we do instead.
2552 We can't use displaced stepping when we are waiting for vfork_done
2553 event, displaced stepping breaks the vfork child similarly as single
2554 step software breakpoint. */
2555 if (tp->control.trap_expected
2556 && use_displaced_stepping (tp)
2557 && !step_over_info_valid_p ()
2558 && sig == GDB_SIGNAL_0
2559 && !current_inferior ()->waiting_for_vfork_done)
2561 int prepared = displaced_step_prepare (inferior_ptid);
2566 fprintf_unfiltered (gdb_stdlog,
2567 "Got placed in step-over queue\n");
2569 tp->control.trap_expected = 0;
2570 discard_cleanups (old_cleanups);
2573 else if (prepared < 0)
2575 /* Fallback to stepping over the breakpoint in-line. */
2577 if (target_is_non_stop_p ())
2578 stop_all_threads ();
2580 set_step_over_info (get_regcache_aspace (regcache),
2581 regcache_read_pc (regcache), 0);
2583 step = maybe_software_singlestep (gdbarch, pc);
2585 insert_breakpoints ();
2587 else if (prepared > 0)
2589 struct displaced_step_inferior_state *displaced;
2591 /* Update pc to reflect the new address from which we will
2592 execute instructions due to displaced stepping. */
2593 pc = regcache_read_pc (get_thread_regcache (inferior_ptid));
2595 displaced = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
2596 step = gdbarch_displaced_step_hw_singlestep (gdbarch,
2597 displaced->step_closure);
2601 /* Do we need to do it the hard way, w/temp breakpoints? */
2603 step = maybe_software_singlestep (gdbarch, pc);
2605 /* Currently, our software single-step implementation leads to different
2606 results than hardware single-stepping in one situation: when stepping
2607 into delivering a signal which has an associated signal handler,
2608 hardware single-step will stop at the first instruction of the handler,
2609 while software single-step will simply skip execution of the handler.
2611 For now, this difference in behavior is accepted since there is no
2612 easy way to actually implement single-stepping into a signal handler
2613 without kernel support.
2615 However, there is one scenario where this difference leads to follow-on
2616 problems: if we're stepping off a breakpoint by removing all breakpoints
2617 and then single-stepping. In this case, the software single-step
2618 behavior means that even if there is a *breakpoint* in the signal
2619 handler, GDB still would not stop.
2621 Fortunately, we can at least fix this particular issue. We detect
2622 here the case where we are about to deliver a signal while software
2623 single-stepping with breakpoints removed. In this situation, we
2624 revert the decisions to remove all breakpoints and insert single-
2625 step breakpoints, and instead we install a step-resume breakpoint
2626 at the current address, deliver the signal without stepping, and
2627 once we arrive back at the step-resume breakpoint, actually step
2628 over the breakpoint we originally wanted to step over. */
2629 if (thread_has_single_step_breakpoints_set (tp)
2630 && sig != GDB_SIGNAL_0
2631 && step_over_info_valid_p ())
2633 /* If we have nested signals or a pending signal is delivered
2634 immediately after a handler returns, might might already have
2635 a step-resume breakpoint set on the earlier handler. We cannot
2636 set another step-resume breakpoint; just continue on until the
2637 original breakpoint is hit. */
2638 if (tp->control.step_resume_breakpoint == NULL)
2640 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2641 tp->step_after_step_resume_breakpoint = 1;
2644 delete_single_step_breakpoints (tp);
2646 clear_step_over_info ();
2647 tp->control.trap_expected = 0;
2649 insert_breakpoints ();
2652 /* If STEP is set, it's a request to use hardware stepping
2653 facilities. But in that case, we should never
2654 use singlestep breakpoint. */
2655 gdb_assert (!(thread_has_single_step_breakpoints_set (tp) && step));
2657 /* Decide the set of threads to ask the target to resume. */
2658 if (tp->control.trap_expected)
2660 /* We're allowing a thread to run past a breakpoint it has
2661 hit, either by single-stepping the thread with the breakpoint
2662 removed, or by displaced stepping, with the breakpoint inserted.
2663 In the former case, we need to single-step only this thread,
2664 and keep others stopped, as they can miss this breakpoint if
2665 allowed to run. That's not really a problem for displaced
2666 stepping, but, we still keep other threads stopped, in case
2667 another thread is also stopped for a breakpoint waiting for
2668 its turn in the displaced stepping queue. */
2669 resume_ptid = inferior_ptid;
2672 resume_ptid = internal_resume_ptid (user_step);
2674 if (execution_direction != EXEC_REVERSE
2675 && step && breakpoint_inserted_here_p (aspace, pc))
2677 /* There are two cases where we currently need to step a
2678 breakpoint instruction when we have a signal to deliver:
2680 - See handle_signal_stop where we handle random signals that
2681 could take out us out of the stepping range. Normally, in
2682 that case we end up continuing (instead of stepping) over the
2683 signal handler with a breakpoint at PC, but there are cases
2684 where we should _always_ single-step, even if we have a
2685 step-resume breakpoint, like when a software watchpoint is
2686 set. Assuming single-stepping and delivering a signal at the
2687 same time would takes us to the signal handler, then we could
2688 have removed the breakpoint at PC to step over it. However,
2689 some hardware step targets (like e.g., Mac OS) can't step
2690 into signal handlers, and for those, we need to leave the
2691 breakpoint at PC inserted, as otherwise if the handler
2692 recurses and executes PC again, it'll miss the breakpoint.
2693 So we leave the breakpoint inserted anyway, but we need to
2694 record that we tried to step a breakpoint instruction, so
2695 that adjust_pc_after_break doesn't end up confused.
2697 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2698 in one thread after another thread that was stepping had been
2699 momentarily paused for a step-over. When we re-resume the
2700 stepping thread, it may be resumed from that address with a
2701 breakpoint that hasn't trapped yet. Seen with
2702 gdb.threads/non-stop-fair-events.exp, on targets that don't
2703 do displaced stepping. */
2706 fprintf_unfiltered (gdb_stdlog,
2707 "infrun: resume: [%s] stepped breakpoint\n",
2708 target_pid_to_str (tp->ptid));
2710 tp->stepped_breakpoint = 1;
2712 /* Most targets can step a breakpoint instruction, thus
2713 executing it normally. But if this one cannot, just
2714 continue and we will hit it anyway. */
2715 if (gdbarch_cannot_step_breakpoint (gdbarch))
2720 && tp->control.trap_expected
2721 && use_displaced_stepping (tp)
2722 && !step_over_info_valid_p ())
2724 struct regcache *resume_regcache = get_thread_regcache (tp->ptid);
2725 struct gdbarch *resume_gdbarch = get_regcache_arch (resume_regcache);
2726 CORE_ADDR actual_pc = regcache_read_pc (resume_regcache);
2729 fprintf_unfiltered (gdb_stdlog, "displaced: run %s: ",
2730 paddress (resume_gdbarch, actual_pc));
2731 read_memory (actual_pc, buf, sizeof (buf));
2732 displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
2735 if (tp->control.may_range_step)
2737 /* If we're resuming a thread with the PC out of the step
2738 range, then we're doing some nested/finer run control
2739 operation, like stepping the thread out of the dynamic
2740 linker or the displaced stepping scratch pad. We
2741 shouldn't have allowed a range step then. */
2742 gdb_assert (pc_in_thread_step_range (pc, tp));
2745 do_target_resume (resume_ptid, step, sig);
2747 discard_cleanups (old_cleanups);
2754 /* Counter that tracks number of user visible stops. This can be used
2755 to tell whether a command has proceeded the inferior past the
2756 current location. This allows e.g., inferior function calls in
2757 breakpoint commands to not interrupt the command list. When the
2758 call finishes successfully, the inferior is standing at the same
2759 breakpoint as if nothing happened (and so we don't call
2761 static ULONGEST current_stop_id;
2768 return current_stop_id;
2771 /* Called when we report a user visible stop. */
2779 /* Clear out all variables saying what to do when inferior is continued.
2780 First do this, then set the ones you want, then call `proceed'. */
2783 clear_proceed_status_thread (struct thread_info *tp)
2786 fprintf_unfiltered (gdb_stdlog,
2787 "infrun: clear_proceed_status_thread (%s)\n",
2788 target_pid_to_str (tp->ptid));
2790 /* If we're starting a new sequence, then the previous finished
2791 single-step is no longer relevant. */
2792 if (tp->suspend.waitstatus_pending_p)
2794 if (tp->suspend.stop_reason == TARGET_STOPPED_BY_SINGLE_STEP)
2797 fprintf_unfiltered (gdb_stdlog,
2798 "infrun: clear_proceed_status: pending "
2799 "event of %s was a finished step. "
2801 target_pid_to_str (tp->ptid));
2803 tp->suspend.waitstatus_pending_p = 0;
2804 tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON;
2806 else if (debug_infrun)
2810 statstr = target_waitstatus_to_string (&tp->suspend.waitstatus);
2811 fprintf_unfiltered (gdb_stdlog,
2812 "infrun: clear_proceed_status_thread: thread %s "
2813 "has pending wait status %s "
2814 "(currently_stepping=%d).\n",
2815 target_pid_to_str (tp->ptid), statstr,
2816 currently_stepping (tp));
2821 /* If this signal should not be seen by program, give it zero.
2822 Used for debugging signals. */
2823 if (!signal_pass_state (tp->suspend.stop_signal))
2824 tp->suspend.stop_signal = GDB_SIGNAL_0;
2826 thread_fsm_delete (tp->thread_fsm);
2827 tp->thread_fsm = NULL;
2829 tp->control.trap_expected = 0;
2830 tp->control.step_range_start = 0;
2831 tp->control.step_range_end = 0;
2832 tp->control.may_range_step = 0;
2833 tp->control.step_frame_id = null_frame_id;
2834 tp->control.step_stack_frame_id = null_frame_id;
2835 tp->control.step_over_calls = STEP_OVER_UNDEBUGGABLE;
2836 tp->control.step_start_function = NULL;
2837 tp->stop_requested = 0;
2839 tp->control.stop_step = 0;
2841 tp->control.proceed_to_finish = 0;
2843 tp->control.command_interp = NULL;
2844 tp->control.stepping_command = 0;
2846 /* Discard any remaining commands or status from previous stop. */
2847 bpstat_clear (&tp->control.stop_bpstat);
2851 clear_proceed_status (int step)
2853 /* With scheduler-locking replay, stop replaying other threads if we're
2854 not replaying the user-visible resume ptid.
2856 This is a convenience feature to not require the user to explicitly
2857 stop replaying the other threads. We're assuming that the user's
2858 intent is to resume tracing the recorded process. */
2859 if (!non_stop && scheduler_mode == schedlock_replay
2860 && target_record_is_replaying (minus_one_ptid)
2861 && !target_record_will_replay (user_visible_resume_ptid (step),
2862 execution_direction))
2863 target_record_stop_replaying ();
2867 struct thread_info *tp;
2870 resume_ptid = user_visible_resume_ptid (step);
2872 /* In all-stop mode, delete the per-thread status of all threads
2873 we're about to resume, implicitly and explicitly. */
2874 ALL_NON_EXITED_THREADS (tp)
2876 if (!ptid_match (tp->ptid, resume_ptid))
2878 clear_proceed_status_thread (tp);
2882 if (!ptid_equal (inferior_ptid, null_ptid))
2884 struct inferior *inferior;
2888 /* If in non-stop mode, only delete the per-thread status of
2889 the current thread. */
2890 clear_proceed_status_thread (inferior_thread ());
2893 inferior = current_inferior ();
2894 inferior->control.stop_soon = NO_STOP_QUIETLY;
2897 observer_notify_about_to_proceed ();
2900 /* Returns true if TP is still stopped at a breakpoint that needs
2901 stepping-over in order to make progress. If the breakpoint is gone
2902 meanwhile, we can skip the whole step-over dance. */
2905 thread_still_needs_step_over_bp (struct thread_info *tp)
2907 if (tp->stepping_over_breakpoint)
2909 struct regcache *regcache = get_thread_regcache (tp->ptid);
2911 if (breakpoint_here_p (get_regcache_aspace (regcache),
2912 regcache_read_pc (regcache))
2913 == ordinary_breakpoint_here)
2916 tp->stepping_over_breakpoint = 0;
2922 /* Check whether thread TP still needs to start a step-over in order
2923 to make progress when resumed. Returns an bitwise or of enum
2924 step_over_what bits, indicating what needs to be stepped over. */
2926 static step_over_what
2927 thread_still_needs_step_over (struct thread_info *tp)
2929 struct inferior *inf = find_inferior_ptid (tp->ptid);
2930 step_over_what what = 0;
2932 if (thread_still_needs_step_over_bp (tp))
2933 what |= STEP_OVER_BREAKPOINT;
2935 if (tp->stepping_over_watchpoint
2936 && !target_have_steppable_watchpoint)
2937 what |= STEP_OVER_WATCHPOINT;
2942 /* Returns true if scheduler locking applies. STEP indicates whether
2943 we're about to do a step/next-like command to a thread. */
2946 schedlock_applies (struct thread_info *tp)
2948 return (scheduler_mode == schedlock_on
2949 || (scheduler_mode == schedlock_step
2950 && tp->control.stepping_command)
2951 || (scheduler_mode == schedlock_replay
2952 && target_record_will_replay (minus_one_ptid,
2953 execution_direction)));
2956 /* Basic routine for continuing the program in various fashions.
2958 ADDR is the address to resume at, or -1 for resume where stopped.
2959 SIGGNAL is the signal to give it, or 0 for none,
2960 or -1 for act according to how it stopped.
2961 STEP is nonzero if should trap after one instruction.
2962 -1 means return after that and print nothing.
2963 You should probably set various step_... variables
2964 before calling here, if you are stepping.
2966 You should call clear_proceed_status before calling proceed. */
2969 proceed (CORE_ADDR addr, enum gdb_signal siggnal)
2971 struct regcache *regcache;
2972 struct gdbarch *gdbarch;
2973 struct thread_info *tp;
2975 struct address_space *aspace;
2977 struct execution_control_state ecss;
2978 struct execution_control_state *ecs = &ecss;
2979 struct cleanup *old_chain;
2982 /* If we're stopped at a fork/vfork, follow the branch set by the
2983 "set follow-fork-mode" command; otherwise, we'll just proceed
2984 resuming the current thread. */
2985 if (!follow_fork ())
2987 /* The target for some reason decided not to resume. */
2989 if (target_can_async_p ())
2990 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
2994 /* We'll update this if & when we switch to a new thread. */
2995 previous_inferior_ptid = inferior_ptid;
2997 regcache = get_current_regcache ();
2998 gdbarch = get_regcache_arch (regcache);
2999 aspace = get_regcache_aspace (regcache);
3000 pc = regcache_read_pc (regcache);
3001 tp = inferior_thread ();
3003 /* Fill in with reasonable starting values. */
3004 init_thread_stepping_state (tp);
3006 gdb_assert (!thread_is_in_step_over_chain (tp));
3008 if (addr == (CORE_ADDR) -1)
3011 && breakpoint_here_p (aspace, pc) == ordinary_breakpoint_here
3012 && execution_direction != EXEC_REVERSE)
3013 /* There is a breakpoint at the address we will resume at,
3014 step one instruction before inserting breakpoints so that
3015 we do not stop right away (and report a second hit at this
3018 Note, we don't do this in reverse, because we won't
3019 actually be executing the breakpoint insn anyway.
3020 We'll be (un-)executing the previous instruction. */
3021 tp->stepping_over_breakpoint = 1;
3022 else if (gdbarch_single_step_through_delay_p (gdbarch)
3023 && gdbarch_single_step_through_delay (gdbarch,
3024 get_current_frame ()))
3025 /* We stepped onto an instruction that needs to be stepped
3026 again before re-inserting the breakpoint, do so. */
3027 tp->stepping_over_breakpoint = 1;
3031 regcache_write_pc (regcache, addr);
3034 if (siggnal != GDB_SIGNAL_DEFAULT)
3035 tp->suspend.stop_signal = siggnal;
3037 /* Record the interpreter that issued the execution command that
3038 caused this thread to resume. If the top level interpreter is
3039 MI/async, and the execution command was a CLI command
3040 (next/step/etc.), we'll want to print stop event output to the MI
3041 console channel (the stepped-to line, etc.), as if the user
3042 entered the execution command on a real GDB console. */
3043 tp->control.command_interp = command_interp ();
3045 resume_ptid = user_visible_resume_ptid (tp->control.stepping_command);
3047 /* If an exception is thrown from this point on, make sure to
3048 propagate GDB's knowledge of the executing state to the
3049 frontend/user running state. */
3050 old_chain = make_cleanup (finish_thread_state_cleanup, &resume_ptid);
3052 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3053 threads (e.g., we might need to set threads stepping over
3054 breakpoints first), from the user/frontend's point of view, all
3055 threads in RESUME_PTID are now running. Unless we're calling an
3056 inferior function, as in that case we pretend the inferior
3057 doesn't run at all. */
3058 if (!tp->control.in_infcall)
3059 set_running (resume_ptid, 1);
3062 fprintf_unfiltered (gdb_stdlog,
3063 "infrun: proceed (addr=%s, signal=%s)\n",
3064 paddress (gdbarch, addr),
3065 gdb_signal_to_symbol_string (siggnal));
3067 annotate_starting ();
3069 /* Make sure that output from GDB appears before output from the
3071 gdb_flush (gdb_stdout);
3073 /* In a multi-threaded task we may select another thread and
3074 then continue or step.
3076 But if a thread that we're resuming had stopped at a breakpoint,
3077 it will immediately cause another breakpoint stop without any
3078 execution (i.e. it will report a breakpoint hit incorrectly). So
3079 we must step over it first.
3081 Look for threads other than the current (TP) that reported a
3082 breakpoint hit and haven't been resumed yet since. */
3084 /* If scheduler locking applies, we can avoid iterating over all
3086 if (!non_stop && !schedlock_applies (tp))
3088 struct thread_info *current = tp;
3090 ALL_NON_EXITED_THREADS (tp)
3092 /* Ignore the current thread here. It's handled
3097 /* Ignore threads of processes we're not resuming. */
3098 if (!ptid_match (tp->ptid, resume_ptid))
3101 if (!thread_still_needs_step_over (tp))
3104 gdb_assert (!thread_is_in_step_over_chain (tp));
3107 fprintf_unfiltered (gdb_stdlog,
3108 "infrun: need to step-over [%s] first\n",
3109 target_pid_to_str (tp->ptid));
3111 thread_step_over_chain_enqueue (tp);
3117 /* Enqueue the current thread last, so that we move all other
3118 threads over their breakpoints first. */
3119 if (tp->stepping_over_breakpoint)
3120 thread_step_over_chain_enqueue (tp);
3122 /* If the thread isn't started, we'll still need to set its prev_pc,
3123 so that switch_back_to_stepped_thread knows the thread hasn't
3124 advanced. Must do this before resuming any thread, as in
3125 all-stop/remote, once we resume we can't send any other packet
3126 until the target stops again. */
3127 tp->prev_pc = regcache_read_pc (regcache);
3129 started = start_step_over ();
3131 if (step_over_info_valid_p ())
3133 /* Either this thread started a new in-line step over, or some
3134 other thread was already doing one. In either case, don't
3135 resume anything else until the step-over is finished. */
3137 else if (started && !target_is_non_stop_p ())
3139 /* A new displaced stepping sequence was started. In all-stop,
3140 we can't talk to the target anymore until it next stops. */
3142 else if (!non_stop && target_is_non_stop_p ())
3144 /* In all-stop, but the target is always in non-stop mode.
3145 Start all other threads that are implicitly resumed too. */
3146 ALL_NON_EXITED_THREADS (tp)
3148 /* Ignore threads of processes we're not resuming. */
3149 if (!ptid_match (tp->ptid, resume_ptid))
3155 fprintf_unfiltered (gdb_stdlog,
3156 "infrun: proceed: [%s] resumed\n",
3157 target_pid_to_str (tp->ptid));
3158 gdb_assert (tp->executing || tp->suspend.waitstatus_pending_p);
3162 if (thread_is_in_step_over_chain (tp))
3165 fprintf_unfiltered (gdb_stdlog,
3166 "infrun: proceed: [%s] needs step-over\n",
3167 target_pid_to_str (tp->ptid));
3172 fprintf_unfiltered (gdb_stdlog,
3173 "infrun: proceed: resuming %s\n",
3174 target_pid_to_str (tp->ptid));
3176 reset_ecs (ecs, tp);
3177 switch_to_thread (tp->ptid);
3178 keep_going_pass_signal (ecs);
3179 if (!ecs->wait_some_more)
3180 error (_("Command aborted."));
3183 else if (!tp->resumed && !thread_is_in_step_over_chain (tp))
3185 /* The thread wasn't started, and isn't queued, run it now. */
3186 reset_ecs (ecs, tp);
3187 switch_to_thread (tp->ptid);
3188 keep_going_pass_signal (ecs);
3189 if (!ecs->wait_some_more)
3190 error (_("Command aborted."));
3193 discard_cleanups (old_chain);
3195 /* Tell the event loop to wait for it to stop. If the target
3196 supports asynchronous execution, it'll do this from within
3198 if (!target_can_async_p ())
3199 mark_async_event_handler (infrun_async_inferior_event_token);
3203 /* Start remote-debugging of a machine over a serial link. */
3206 start_remote (int from_tty)
3208 struct inferior *inferior;
3210 inferior = current_inferior ();
3211 inferior->control.stop_soon = STOP_QUIETLY_REMOTE;
3213 /* Always go on waiting for the target, regardless of the mode. */
3214 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3215 indicate to wait_for_inferior that a target should timeout if
3216 nothing is returned (instead of just blocking). Because of this,
3217 targets expecting an immediate response need to, internally, set
3218 things up so that the target_wait() is forced to eventually
3220 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3221 differentiate to its caller what the state of the target is after
3222 the initial open has been performed. Here we're assuming that
3223 the target has stopped. It should be possible to eventually have
3224 target_open() return to the caller an indication that the target
3225 is currently running and GDB state should be set to the same as
3226 for an async run. */
3227 wait_for_inferior ();
3229 /* Now that the inferior has stopped, do any bookkeeping like
3230 loading shared libraries. We want to do this before normal_stop,
3231 so that the displayed frame is up to date. */
3232 post_create_inferior (¤t_target, from_tty);
3237 /* Initialize static vars when a new inferior begins. */
3240 init_wait_for_inferior (void)
3242 /* These are meaningless until the first time through wait_for_inferior. */
3244 breakpoint_init_inferior (inf_starting);
3246 clear_proceed_status (0);
3248 target_last_wait_ptid = minus_one_ptid;
3250 previous_inferior_ptid = inferior_ptid;
3252 /* Discard any skipped inlined frames. */
3253 clear_inline_frame_state (minus_one_ptid);
3258 static void handle_inferior_event (struct execution_control_state *ecs);
3260 static void handle_step_into_function (struct gdbarch *gdbarch,
3261 struct execution_control_state *ecs);
3262 static void handle_step_into_function_backward (struct gdbarch *gdbarch,
3263 struct execution_control_state *ecs);
3264 static void handle_signal_stop (struct execution_control_state *ecs);
3265 static void check_exception_resume (struct execution_control_state *,
3266 struct frame_info *);
3268 static void end_stepping_range (struct execution_control_state *ecs);
3269 static void stop_waiting (struct execution_control_state *ecs);
3270 static void keep_going (struct execution_control_state *ecs);
3271 static void process_event_stop_test (struct execution_control_state *ecs);
3272 static int switch_back_to_stepped_thread (struct execution_control_state *ecs);
3274 /* Callback for iterate over threads. If the thread is stopped, but
3275 the user/frontend doesn't know about that yet, go through
3276 normal_stop, as if the thread had just stopped now. ARG points at
3277 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
3278 ptid_is_pid(PTID) is true, applies to all threads of the process
3279 pointed at by PTID. Otherwise, apply only to the thread pointed by
3283 infrun_thread_stop_requested_callback (struct thread_info *info, void *arg)
3285 ptid_t ptid = * (ptid_t *) arg;
3287 if ((ptid_equal (info->ptid, ptid)
3288 || ptid_equal (minus_one_ptid, ptid)
3289 || (ptid_is_pid (ptid)
3290 && ptid_get_pid (ptid) == ptid_get_pid (info->ptid)))
3291 && is_running (info->ptid)
3292 && !is_executing (info->ptid))
3294 struct cleanup *old_chain;
3295 struct execution_control_state ecss;
3296 struct execution_control_state *ecs = &ecss;
3298 memset (ecs, 0, sizeof (*ecs));
3300 old_chain = make_cleanup_restore_current_thread ();
3302 overlay_cache_invalid = 1;
3303 /* Flush target cache before starting to handle each event.
3304 Target was running and cache could be stale. This is just a
3305 heuristic. Running threads may modify target memory, but we
3306 don't get any event. */
3307 target_dcache_invalidate ();
3309 /* Go through handle_inferior_event/normal_stop, so we always
3310 have consistent output as if the stop event had been
3312 ecs->ptid = info->ptid;
3313 ecs->event_thread = info;
3314 ecs->ws.kind = TARGET_WAITKIND_STOPPED;
3315 ecs->ws.value.sig = GDB_SIGNAL_0;
3317 handle_inferior_event (ecs);
3319 if (!ecs->wait_some_more)
3321 /* Cancel any running execution command. */
3322 thread_cancel_execution_command (info);
3327 do_cleanups (old_chain);
3333 /* This function is attached as a "thread_stop_requested" observer.
3334 Cleanup local state that assumed the PTID was to be resumed, and
3335 report the stop to the frontend. */
3338 infrun_thread_stop_requested (ptid_t ptid)
3340 struct thread_info *tp;
3342 /* PTID was requested to stop. Remove matching threads from the
3343 step-over queue, so we don't try to resume them
3345 ALL_NON_EXITED_THREADS (tp)
3346 if (ptid_match (tp->ptid, ptid))
3348 if (thread_is_in_step_over_chain (tp))
3349 thread_step_over_chain_remove (tp);
3352 iterate_over_threads (infrun_thread_stop_requested_callback, &ptid);
3356 infrun_thread_thread_exit (struct thread_info *tp, int silent)
3358 if (ptid_equal (target_last_wait_ptid, tp->ptid))
3359 nullify_last_target_wait_ptid ();
3362 /* Delete the step resume, single-step and longjmp/exception resume
3363 breakpoints of TP. */
3366 delete_thread_infrun_breakpoints (struct thread_info *tp)
3368 delete_step_resume_breakpoint (tp);
3369 delete_exception_resume_breakpoint (tp);
3370 delete_single_step_breakpoints (tp);
3373 /* If the target still has execution, call FUNC for each thread that
3374 just stopped. In all-stop, that's all the non-exited threads; in
3375 non-stop, that's the current thread, only. */
3377 typedef void (*for_each_just_stopped_thread_callback_func)
3378 (struct thread_info *tp);
3381 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func)
3383 if (!target_has_execution || ptid_equal (inferior_ptid, null_ptid))
3386 if (target_is_non_stop_p ())
3388 /* If in non-stop mode, only the current thread stopped. */
3389 func (inferior_thread ());
3393 struct thread_info *tp;
3395 /* In all-stop mode, all threads have stopped. */
3396 ALL_NON_EXITED_THREADS (tp)
3403 /* Delete the step resume and longjmp/exception resume breakpoints of
3404 the threads that just stopped. */
3407 delete_just_stopped_threads_infrun_breakpoints (void)
3409 for_each_just_stopped_thread (delete_thread_infrun_breakpoints);
3412 /* Delete the single-step breakpoints of the threads that just
3416 delete_just_stopped_threads_single_step_breakpoints (void)
3418 for_each_just_stopped_thread (delete_single_step_breakpoints);
3421 /* A cleanup wrapper. */
3424 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg)
3426 delete_just_stopped_threads_infrun_breakpoints ();
3432 print_target_wait_results (ptid_t waiton_ptid, ptid_t result_ptid,
3433 const struct target_waitstatus *ws)
3435 char *status_string = target_waitstatus_to_string (ws);
3436 struct ui_file *tmp_stream = mem_fileopen ();
3439 /* The text is split over several lines because it was getting too long.
3440 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3441 output as a unit; we want only one timestamp printed if debug_timestamp
3444 fprintf_unfiltered (tmp_stream,
3445 "infrun: target_wait (%d.%ld.%ld",
3446 ptid_get_pid (waiton_ptid),
3447 ptid_get_lwp (waiton_ptid),
3448 ptid_get_tid (waiton_ptid));
3449 if (ptid_get_pid (waiton_ptid) != -1)
3450 fprintf_unfiltered (tmp_stream,
3451 " [%s]", target_pid_to_str (waiton_ptid));
3452 fprintf_unfiltered (tmp_stream, ", status) =\n");
3453 fprintf_unfiltered (tmp_stream,
3454 "infrun: %d.%ld.%ld [%s],\n",
3455 ptid_get_pid (result_ptid),
3456 ptid_get_lwp (result_ptid),
3457 ptid_get_tid (result_ptid),
3458 target_pid_to_str (result_ptid));
3459 fprintf_unfiltered (tmp_stream,
3463 text = ui_file_xstrdup (tmp_stream, NULL);
3465 /* This uses %s in part to handle %'s in the text, but also to avoid
3466 a gcc error: the format attribute requires a string literal. */
3467 fprintf_unfiltered (gdb_stdlog, "%s", text);
3469 xfree (status_string);
3471 ui_file_delete (tmp_stream);
3474 /* Select a thread at random, out of those which are resumed and have
3477 static struct thread_info *
3478 random_pending_event_thread (ptid_t waiton_ptid)
3480 struct thread_info *event_tp;
3482 int random_selector;
3484 /* First see how many events we have. Count only resumed threads
3485 that have an event pending. */
3486 ALL_NON_EXITED_THREADS (event_tp)
3487 if (ptid_match (event_tp->ptid, waiton_ptid)
3488 && event_tp->resumed
3489 && event_tp->suspend.waitstatus_pending_p)
3492 if (num_events == 0)
3495 /* Now randomly pick a thread out of those that have had events. */
3496 random_selector = (int)
3497 ((num_events * (double) rand ()) / (RAND_MAX + 1.0));
3499 if (debug_infrun && num_events > 1)
3500 fprintf_unfiltered (gdb_stdlog,
3501 "infrun: Found %d events, selecting #%d\n",
3502 num_events, random_selector);
3504 /* Select the Nth thread that has had an event. */
3505 ALL_NON_EXITED_THREADS (event_tp)
3506 if (ptid_match (event_tp->ptid, waiton_ptid)
3507 && event_tp->resumed
3508 && event_tp->suspend.waitstatus_pending_p)
3509 if (random_selector-- == 0)
3515 /* Wrapper for target_wait that first checks whether threads have
3516 pending statuses to report before actually asking the target for
3520 do_target_wait (ptid_t ptid, struct target_waitstatus *status, int options)
3523 struct thread_info *tp;
3525 /* First check if there is a resumed thread with a wait status
3527 if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid))
3529 tp = random_pending_event_thread (ptid);
3534 fprintf_unfiltered (gdb_stdlog,
3535 "infrun: Waiting for specific thread %s.\n",
3536 target_pid_to_str (ptid));
3538 /* We have a specific thread to check. */
3539 tp = find_thread_ptid (ptid);
3540 gdb_assert (tp != NULL);
3541 if (!tp->suspend.waitstatus_pending_p)
3546 && (tp->suspend.stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3547 || tp->suspend.stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT))
3549 struct regcache *regcache = get_thread_regcache (tp->ptid);
3550 struct gdbarch *gdbarch = get_regcache_arch (regcache);
3554 pc = regcache_read_pc (regcache);
3556 if (pc != tp->suspend.stop_pc)
3559 fprintf_unfiltered (gdb_stdlog,
3560 "infrun: PC of %s changed. was=%s, now=%s\n",
3561 target_pid_to_str (tp->ptid),
3562 paddress (gdbarch, tp->prev_pc),
3563 paddress (gdbarch, pc));
3566 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc))
3569 fprintf_unfiltered (gdb_stdlog,
3570 "infrun: previous breakpoint of %s, at %s gone\n",
3571 target_pid_to_str (tp->ptid),
3572 paddress (gdbarch, pc));
3580 fprintf_unfiltered (gdb_stdlog,
3581 "infrun: pending event of %s cancelled.\n",
3582 target_pid_to_str (tp->ptid));
3584 tp->suspend.waitstatus.kind = TARGET_WAITKIND_SPURIOUS;
3585 tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON;
3595 statstr = target_waitstatus_to_string (&tp->suspend.waitstatus);
3596 fprintf_unfiltered (gdb_stdlog,
3597 "infrun: Using pending wait status %s for %s.\n",
3599 target_pid_to_str (tp->ptid));
3603 /* Now that we've selected our final event LWP, un-adjust its PC
3604 if it was a software breakpoint (and the target doesn't
3605 always adjust the PC itself). */
3606 if (tp->suspend.stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3607 && !target_supports_stopped_by_sw_breakpoint ())
3609 struct regcache *regcache;
3610 struct gdbarch *gdbarch;
3613 regcache = get_thread_regcache (tp->ptid);
3614 gdbarch = get_regcache_arch (regcache);
3616 decr_pc = gdbarch_decr_pc_after_break (gdbarch);
3621 pc = regcache_read_pc (regcache);
3622 regcache_write_pc (regcache, pc + decr_pc);
3626 tp->suspend.stop_reason = TARGET_STOPPED_BY_NO_REASON;
3627 *status = tp->suspend.waitstatus;
3628 tp->suspend.waitstatus_pending_p = 0;
3630 /* Wake up the event loop again, until all pending events are
3632 if (target_is_async_p ())
3633 mark_async_event_handler (infrun_async_inferior_event_token);
3637 /* But if we don't find one, we'll have to wait. */
3639 if (deprecated_target_wait_hook)
3640 event_ptid = deprecated_target_wait_hook (ptid, status, options);
3642 event_ptid = target_wait (ptid, status, options);
3647 /* Prepare and stabilize the inferior for detaching it. E.g.,
3648 detaching while a thread is displaced stepping is a recipe for
3649 crashing it, as nothing would readjust the PC out of the scratch
3653 prepare_for_detach (void)
3655 struct inferior *inf = current_inferior ();
3656 ptid_t pid_ptid = pid_to_ptid (inf->pid);
3657 struct cleanup *old_chain_1;
3658 struct displaced_step_inferior_state *displaced;
3660 displaced = get_displaced_stepping_state (inf->pid);
3662 /* Is any thread of this process displaced stepping? If not,
3663 there's nothing else to do. */
3664 if (displaced == NULL || ptid_equal (displaced->step_ptid, null_ptid))
3668 fprintf_unfiltered (gdb_stdlog,
3669 "displaced-stepping in-process while detaching");
3671 old_chain_1 = make_cleanup_restore_integer (&inf->detaching);
3674 while (!ptid_equal (displaced->step_ptid, null_ptid))
3676 struct cleanup *old_chain_2;
3677 struct execution_control_state ecss;
3678 struct execution_control_state *ecs;
3681 memset (ecs, 0, sizeof (*ecs));
3683 overlay_cache_invalid = 1;
3684 /* Flush target cache before starting to handle each event.
3685 Target was running and cache could be stale. This is just a
3686 heuristic. Running threads may modify target memory, but we
3687 don't get any event. */
3688 target_dcache_invalidate ();
3690 ecs->ptid = do_target_wait (pid_ptid, &ecs->ws, 0);
3693 print_target_wait_results (pid_ptid, ecs->ptid, &ecs->ws);
3695 /* If an error happens while handling the event, propagate GDB's
3696 knowledge of the executing state to the frontend/user running
3698 old_chain_2 = make_cleanup (finish_thread_state_cleanup,
3701 /* Now figure out what to do with the result of the result. */
3702 handle_inferior_event (ecs);
3704 /* No error, don't finish the state yet. */
3705 discard_cleanups (old_chain_2);
3707 /* Breakpoints and watchpoints are not installed on the target
3708 at this point, and signals are passed directly to the
3709 inferior, so this must mean the process is gone. */
3710 if (!ecs->wait_some_more)
3712 discard_cleanups (old_chain_1);
3713 error (_("Program exited while detaching"));
3717 discard_cleanups (old_chain_1);
3720 /* Wait for control to return from inferior to debugger.
3722 If inferior gets a signal, we may decide to start it up again
3723 instead of returning. That is why there is a loop in this function.
3724 When this function actually returns it means the inferior
3725 should be left stopped and GDB should read more commands. */
3728 wait_for_inferior (void)
3730 struct cleanup *old_cleanups;
3731 struct cleanup *thread_state_chain;
3735 (gdb_stdlog, "infrun: wait_for_inferior ()\n");
3738 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup,
3741 /* If an error happens while handling the event, propagate GDB's
3742 knowledge of the executing state to the frontend/user running
3744 thread_state_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
3748 struct execution_control_state ecss;
3749 struct execution_control_state *ecs = &ecss;
3750 ptid_t waiton_ptid = minus_one_ptid;
3752 memset (ecs, 0, sizeof (*ecs));
3754 overlay_cache_invalid = 1;
3756 /* Flush target cache before starting to handle each event.
3757 Target was running and cache could be stale. This is just a
3758 heuristic. Running threads may modify target memory, but we
3759 don't get any event. */
3760 target_dcache_invalidate ();
3762 ecs->ptid = do_target_wait (waiton_ptid, &ecs->ws, 0);
3765 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
3767 /* Now figure out what to do with the result of the result. */
3768 handle_inferior_event (ecs);
3770 if (!ecs->wait_some_more)
3774 /* No error, don't finish the state yet. */
3775 discard_cleanups (thread_state_chain);
3777 do_cleanups (old_cleanups);
3780 /* Cleanup that reinstalls the readline callback handler, if the
3781 target is running in the background. If while handling the target
3782 event something triggered a secondary prompt, like e.g., a
3783 pagination prompt, we'll have removed the callback handler (see
3784 gdb_readline_wrapper_line). Need to do this as we go back to the
3785 event loop, ready to process further input. Note this has no
3786 effect if the handler hasn't actually been removed, because calling
3787 rl_callback_handler_install resets the line buffer, thus losing
3791 reinstall_readline_callback_handler_cleanup (void *arg)
3793 if (!interpreter_async)
3795 /* We're not going back to the top level event loop yet. Don't
3796 install the readline callback, as it'd prep the terminal,
3797 readline-style (raw, noecho) (e.g., --batch). We'll install
3798 it the next time the prompt is displayed, when we're ready
3803 if (async_command_editing_p && !sync_execution)
3804 gdb_rl_callback_handler_reinstall ();
3807 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3808 that's just the event thread. In all-stop, that's all threads. */
3811 clean_up_just_stopped_threads_fsms (struct execution_control_state *ecs)
3813 struct thread_info *thr = ecs->event_thread;
3815 if (thr != NULL && thr->thread_fsm != NULL)
3816 thread_fsm_clean_up (thr->thread_fsm);
3820 ALL_NON_EXITED_THREADS (thr)
3822 if (thr->thread_fsm == NULL)
3824 if (thr == ecs->event_thread)
3827 switch_to_thread (thr->ptid);
3828 thread_fsm_clean_up (thr->thread_fsm);
3831 if (ecs->event_thread != NULL)
3832 switch_to_thread (ecs->event_thread->ptid);
3836 /* A cleanup that restores the execution direction to the value saved
3840 restore_execution_direction (void *arg)
3842 enum exec_direction_kind *save_exec_dir = (enum exec_direction_kind *) arg;
3844 execution_direction = *save_exec_dir;
3847 /* Asynchronous version of wait_for_inferior. It is called by the
3848 event loop whenever a change of state is detected on the file
3849 descriptor corresponding to the target. It can be called more than
3850 once to complete a single execution command. In such cases we need
3851 to keep the state in a global variable ECSS. If it is the last time
3852 that this function is called for a single execution command, then
3853 report to the user that the inferior has stopped, and do the
3854 necessary cleanups. */
3857 fetch_inferior_event (void *client_data)
3859 struct execution_control_state ecss;
3860 struct execution_control_state *ecs = &ecss;
3861 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
3862 struct cleanup *ts_old_chain;
3863 int was_sync = sync_execution;
3864 enum exec_direction_kind save_exec_dir = execution_direction;
3866 ptid_t waiton_ptid = minus_one_ptid;
3868 memset (ecs, 0, sizeof (*ecs));
3870 /* End up with readline processing input, if necessary. */
3871 make_cleanup (reinstall_readline_callback_handler_cleanup, NULL);
3873 /* We're handling a live event, so make sure we're doing live
3874 debugging. If we're looking at traceframes while the target is
3875 running, we're going to need to get back to that mode after
3876 handling the event. */
3879 make_cleanup_restore_current_traceframe ();
3880 set_current_traceframe (-1);
3884 /* In non-stop mode, the user/frontend should not notice a thread
3885 switch due to internal events. Make sure we reverse to the
3886 user selected thread and frame after handling the event and
3887 running any breakpoint commands. */
3888 make_cleanup_restore_current_thread ();
3890 overlay_cache_invalid = 1;
3891 /* Flush target cache before starting to handle each event. Target
3892 was running and cache could be stale. This is just a heuristic.
3893 Running threads may modify target memory, but we don't get any
3895 target_dcache_invalidate ();
3897 make_cleanup (restore_execution_direction, &save_exec_dir);
3898 execution_direction = target_execution_direction ();
3900 ecs->ptid = do_target_wait (waiton_ptid, &ecs->ws,
3901 target_can_async_p () ? TARGET_WNOHANG : 0);
3904 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
3906 /* If an error happens while handling the event, propagate GDB's
3907 knowledge of the executing state to the frontend/user running
3909 if (!target_is_non_stop_p ())
3910 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
3912 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &ecs->ptid);
3914 /* Get executed before make_cleanup_restore_current_thread above to apply
3915 still for the thread which has thrown the exception. */
3916 make_bpstat_clear_actions_cleanup ();
3918 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup, NULL);
3920 /* Now figure out what to do with the result of the result. */
3921 handle_inferior_event (ecs);
3923 if (!ecs->wait_some_more)
3925 struct inferior *inf = find_inferior_ptid (ecs->ptid);
3926 int should_stop = 1;
3927 struct thread_info *thr = ecs->event_thread;
3928 int should_notify_stop = 1;
3930 delete_just_stopped_threads_infrun_breakpoints ();
3934 struct thread_fsm *thread_fsm = thr->thread_fsm;
3936 if (thread_fsm != NULL)
3937 should_stop = thread_fsm_should_stop (thread_fsm);
3946 clean_up_just_stopped_threads_fsms (ecs);
3948 if (thr != NULL && thr->thread_fsm != NULL)
3951 = thread_fsm_should_notify_stop (thr->thread_fsm);
3954 if (should_notify_stop)
3958 /* We may not find an inferior if this was a process exit. */
3959 if (inf == NULL || inf->control.stop_soon == NO_STOP_QUIETLY)
3960 proceeded = normal_stop ();
3964 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
3971 /* No error, don't finish the thread states yet. */
3972 discard_cleanups (ts_old_chain);
3974 /* Revert thread and frame. */
3975 do_cleanups (old_chain);
3977 /* If the inferior was in sync execution mode, and now isn't,
3978 restore the prompt (a synchronous execution command has finished,
3979 and we're ready for input). */
3980 if (interpreter_async && was_sync && !sync_execution)
3981 observer_notify_sync_execution_done ();
3985 && exec_done_display_p
3986 && (ptid_equal (inferior_ptid, null_ptid)
3987 || !is_running (inferior_ptid)))
3988 printf_unfiltered (_("completed.\n"));
3991 /* Record the frame and location we're currently stepping through. */
3993 set_step_info (struct frame_info *frame, struct symtab_and_line sal)
3995 struct thread_info *tp = inferior_thread ();
3997 tp->control.step_frame_id = get_frame_id (frame);
3998 tp->control.step_stack_frame_id = get_stack_frame_id (frame);
4000 tp->current_symtab = sal.symtab;
4001 tp->current_line = sal.line;
4004 /* Clear context switchable stepping state. */
4007 init_thread_stepping_state (struct thread_info *tss)
4009 tss->stepped_breakpoint = 0;
4010 tss->stepping_over_breakpoint = 0;
4011 tss->stepping_over_watchpoint = 0;
4012 tss->step_after_step_resume_breakpoint = 0;
4015 /* Set the cached copy of the last ptid/waitstatus. */
4018 set_last_target_status (ptid_t ptid, struct target_waitstatus status)
4020 target_last_wait_ptid = ptid;
4021 target_last_waitstatus = status;
4024 /* Return the cached copy of the last pid/waitstatus returned by
4025 target_wait()/deprecated_target_wait_hook(). The data is actually
4026 cached by handle_inferior_event(), which gets called immediately
4027 after target_wait()/deprecated_target_wait_hook(). */
4030 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
4032 *ptidp = target_last_wait_ptid;
4033 *status = target_last_waitstatus;
4037 nullify_last_target_wait_ptid (void)
4039 target_last_wait_ptid = minus_one_ptid;
4042 /* Switch thread contexts. */
4045 context_switch (ptid_t ptid)
4047 if (debug_infrun && !ptid_equal (ptid, inferior_ptid))
4049 fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ",
4050 target_pid_to_str (inferior_ptid));
4051 fprintf_unfiltered (gdb_stdlog, "to %s\n",
4052 target_pid_to_str (ptid));
4055 switch_to_thread (ptid);
4058 /* If the target can't tell whether we've hit breakpoints
4059 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4060 check whether that could have been caused by a breakpoint. If so,
4061 adjust the PC, per gdbarch_decr_pc_after_break. */
4064 adjust_pc_after_break (struct thread_info *thread,
4065 struct target_waitstatus *ws)
4067 struct regcache *regcache;
4068 struct gdbarch *gdbarch;
4069 struct address_space *aspace;
4070 CORE_ADDR breakpoint_pc, decr_pc;
4072 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4073 we aren't, just return.
4075 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4076 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4077 implemented by software breakpoints should be handled through the normal
4080 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4081 different signals (SIGILL or SIGEMT for instance), but it is less
4082 clear where the PC is pointing afterwards. It may not match
4083 gdbarch_decr_pc_after_break. I don't know any specific target that
4084 generates these signals at breakpoints (the code has been in GDB since at
4085 least 1992) so I can not guess how to handle them here.
4087 In earlier versions of GDB, a target with
4088 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4089 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4090 target with both of these set in GDB history, and it seems unlikely to be
4091 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4093 if (ws->kind != TARGET_WAITKIND_STOPPED)
4096 if (ws->value.sig != GDB_SIGNAL_TRAP)
4099 /* In reverse execution, when a breakpoint is hit, the instruction
4100 under it has already been de-executed. The reported PC always
4101 points at the breakpoint address, so adjusting it further would
4102 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4105 B1 0x08000000 : INSN1
4106 B2 0x08000001 : INSN2
4108 PC -> 0x08000003 : INSN4
4110 Say you're stopped at 0x08000003 as above. Reverse continuing
4111 from that point should hit B2 as below. Reading the PC when the
4112 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4113 been de-executed already.
4115 B1 0x08000000 : INSN1
4116 B2 PC -> 0x08000001 : INSN2
4120 We can't apply the same logic as for forward execution, because
4121 we would wrongly adjust the PC to 0x08000000, since there's a
4122 breakpoint at PC - 1. We'd then report a hit on B1, although
4123 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4125 if (execution_direction == EXEC_REVERSE)
4128 /* If the target can tell whether the thread hit a SW breakpoint,
4129 trust it. Targets that can tell also adjust the PC
4131 if (target_supports_stopped_by_sw_breakpoint ())
4134 /* Note that relying on whether a breakpoint is planted in memory to
4135 determine this can fail. E.g,. the breakpoint could have been
4136 removed since. Or the thread could have been told to step an
4137 instruction the size of a breakpoint instruction, and only
4138 _after_ was a breakpoint inserted at its address. */
4140 /* If this target does not decrement the PC after breakpoints, then
4141 we have nothing to do. */
4142 regcache = get_thread_regcache (thread->ptid);
4143 gdbarch = get_regcache_arch (regcache);
4145 decr_pc = gdbarch_decr_pc_after_break (gdbarch);
4149 aspace = get_regcache_aspace (regcache);
4151 /* Find the location where (if we've hit a breakpoint) the
4152 breakpoint would be. */
4153 breakpoint_pc = regcache_read_pc (regcache) - decr_pc;
4155 /* If the target can't tell whether a software breakpoint triggered,
4156 fallback to figuring it out based on breakpoints we think were
4157 inserted in the target, and on whether the thread was stepped or
4160 /* Check whether there actually is a software breakpoint inserted at
4163 If in non-stop mode, a race condition is possible where we've
4164 removed a breakpoint, but stop events for that breakpoint were
4165 already queued and arrive later. To suppress those spurious
4166 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4167 and retire them after a number of stop events are reported. Note
4168 this is an heuristic and can thus get confused. The real fix is
4169 to get the "stopped by SW BP and needs adjustment" info out of
4170 the target/kernel (and thus never reach here; see above). */
4171 if (software_breakpoint_inserted_here_p (aspace, breakpoint_pc)
4172 || (target_is_non_stop_p ()
4173 && moribund_breakpoint_here_p (aspace, breakpoint_pc)))
4175 struct cleanup *old_cleanups = make_cleanup (null_cleanup, NULL);
4177 if (record_full_is_used ())
4178 record_full_gdb_operation_disable_set ();
4180 /* When using hardware single-step, a SIGTRAP is reported for both
4181 a completed single-step and a software breakpoint. Need to
4182 differentiate between the two, as the latter needs adjusting
4183 but the former does not.
4185 The SIGTRAP can be due to a completed hardware single-step only if
4186 - we didn't insert software single-step breakpoints
4187 - this thread is currently being stepped
4189 If any of these events did not occur, we must have stopped due
4190 to hitting a software breakpoint, and have to back up to the
4193 As a special case, we could have hardware single-stepped a
4194 software breakpoint. In this case (prev_pc == breakpoint_pc),
4195 we also need to back up to the breakpoint address. */
4197 if (thread_has_single_step_breakpoints_set (thread)
4198 || !currently_stepping (thread)
4199 || (thread->stepped_breakpoint
4200 && thread->prev_pc == breakpoint_pc))
4201 regcache_write_pc (regcache, breakpoint_pc);
4203 do_cleanups (old_cleanups);
4208 stepped_in_from (struct frame_info *frame, struct frame_id step_frame_id)
4210 for (frame = get_prev_frame (frame);
4212 frame = get_prev_frame (frame))
4214 if (frame_id_eq (get_frame_id (frame), step_frame_id))
4216 if (get_frame_type (frame) != INLINE_FRAME)
4223 /* Auxiliary function that handles syscall entry/return events.
4224 It returns 1 if the inferior should keep going (and GDB
4225 should ignore the event), or 0 if the event deserves to be
4229 handle_syscall_event (struct execution_control_state *ecs)
4231 struct regcache *regcache;
4234 if (!ptid_equal (ecs->ptid, inferior_ptid))
4235 context_switch (ecs->ptid);
4237 regcache = get_thread_regcache (ecs->ptid);
4238 syscall_number = ecs->ws.value.syscall_number;
4239 stop_pc = regcache_read_pc (regcache);
4241 if (catch_syscall_enabled () > 0
4242 && catching_syscall_number (syscall_number) > 0)
4245 fprintf_unfiltered (gdb_stdlog, "infrun: syscall number = '%d'\n",
4248 ecs->event_thread->control.stop_bpstat
4249 = bpstat_stop_status (get_regcache_aspace (regcache),
4250 stop_pc, ecs->ptid, &ecs->ws);
4252 if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
4254 /* Catchpoint hit. */
4259 /* If no catchpoint triggered for this, then keep going. */
4264 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4267 fill_in_stop_func (struct gdbarch *gdbarch,
4268 struct execution_control_state *ecs)
4270 if (!ecs->stop_func_filled_in)
4272 /* Don't care about return value; stop_func_start and stop_func_name
4273 will both be 0 if it doesn't work. */
4274 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
4275 &ecs->stop_func_start, &ecs->stop_func_end);
4276 ecs->stop_func_start
4277 += gdbarch_deprecated_function_start_offset (gdbarch);
4279 if (gdbarch_skip_entrypoint_p (gdbarch))
4280 ecs->stop_func_start = gdbarch_skip_entrypoint (gdbarch,
4281 ecs->stop_func_start);
4283 ecs->stop_func_filled_in = 1;
4288 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4290 static enum stop_kind
4291 get_inferior_stop_soon (ptid_t ptid)
4293 struct inferior *inf = find_inferior_ptid (ptid);
4295 gdb_assert (inf != NULL);
4296 return inf->control.stop_soon;
4299 /* Wait for one event. Store the resulting waitstatus in WS, and
4300 return the event ptid. */
4303 wait_one (struct target_waitstatus *ws)
4306 ptid_t wait_ptid = minus_one_ptid;
4308 overlay_cache_invalid = 1;
4310 /* Flush target cache before starting to handle each event.
4311 Target was running and cache could be stale. This is just a
4312 heuristic. Running threads may modify target memory, but we
4313 don't get any event. */
4314 target_dcache_invalidate ();
4316 if (deprecated_target_wait_hook)
4317 event_ptid = deprecated_target_wait_hook (wait_ptid, ws, 0);
4319 event_ptid = target_wait (wait_ptid, ws, 0);
4322 print_target_wait_results (wait_ptid, event_ptid, ws);
4327 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4328 instead of the current thread. */
4329 #define THREAD_STOPPED_BY(REASON) \
4331 thread_stopped_by_ ## REASON (ptid_t ptid) \
4333 struct cleanup *old_chain; \
4336 old_chain = save_inferior_ptid (); \
4337 inferior_ptid = ptid; \
4339 res = target_stopped_by_ ## REASON (); \
4341 do_cleanups (old_chain); \
4346 /* Generate thread_stopped_by_watchpoint. */
4347 THREAD_STOPPED_BY (watchpoint)
4348 /* Generate thread_stopped_by_sw_breakpoint. */
4349 THREAD_STOPPED_BY (sw_breakpoint)
4350 /* Generate thread_stopped_by_hw_breakpoint. */
4351 THREAD_STOPPED_BY (hw_breakpoint)
4353 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4356 switch_to_thread_cleanup (void *ptid_p)
4358 ptid_t ptid = *(ptid_t *) ptid_p;
4360 switch_to_thread (ptid);
4363 /* Save the thread's event and stop reason to process it later. */
4366 save_waitstatus (struct thread_info *tp, struct target_waitstatus *ws)
4368 struct regcache *regcache;
4369 struct address_space *aspace;
4375 statstr = target_waitstatus_to_string (ws);
4376 fprintf_unfiltered (gdb_stdlog,
4377 "infrun: saving status %s for %d.%ld.%ld\n",
4379 ptid_get_pid (tp->ptid),
4380 ptid_get_lwp (tp->ptid),
4381 ptid_get_tid (tp->ptid));
4385 /* Record for later. */
4386 tp->suspend.waitstatus = *ws;
4387 tp->suspend.waitstatus_pending_p = 1;
4389 regcache = get_thread_regcache (tp->ptid);
4390 aspace = get_regcache_aspace (regcache);
4392 if (ws->kind == TARGET_WAITKIND_STOPPED
4393 && ws->value.sig == GDB_SIGNAL_TRAP)
4395 CORE_ADDR pc = regcache_read_pc (regcache);
4397 adjust_pc_after_break (tp, &tp->suspend.waitstatus);
4399 if (thread_stopped_by_watchpoint (tp->ptid))
4401 tp->suspend.stop_reason
4402 = TARGET_STOPPED_BY_WATCHPOINT;
4404 else if (target_supports_stopped_by_sw_breakpoint ()
4405 && thread_stopped_by_sw_breakpoint (tp->ptid))
4407 tp->suspend.stop_reason
4408 = TARGET_STOPPED_BY_SW_BREAKPOINT;
4410 else if (target_supports_stopped_by_hw_breakpoint ()
4411 && thread_stopped_by_hw_breakpoint (tp->ptid))
4413 tp->suspend.stop_reason
4414 = TARGET_STOPPED_BY_HW_BREAKPOINT;
4416 else if (!target_supports_stopped_by_hw_breakpoint ()
4417 && hardware_breakpoint_inserted_here_p (aspace,
4420 tp->suspend.stop_reason
4421 = TARGET_STOPPED_BY_HW_BREAKPOINT;
4423 else if (!target_supports_stopped_by_sw_breakpoint ()
4424 && software_breakpoint_inserted_here_p (aspace,
4427 tp->suspend.stop_reason
4428 = TARGET_STOPPED_BY_SW_BREAKPOINT;
4430 else if (!thread_has_single_step_breakpoints_set (tp)
4431 && currently_stepping (tp))
4433 tp->suspend.stop_reason
4434 = TARGET_STOPPED_BY_SINGLE_STEP;
4439 /* A cleanup that disables thread create/exit events. */
4442 disable_thread_events (void *arg)
4444 target_thread_events (0);
4450 stop_all_threads (void)
4452 /* We may need multiple passes to discover all threads. */
4456 struct cleanup *old_chain;
4458 gdb_assert (target_is_non_stop_p ());
4461 fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads\n");
4463 entry_ptid = inferior_ptid;
4464 old_chain = make_cleanup (switch_to_thread_cleanup, &entry_ptid);
4466 target_thread_events (1);
4467 make_cleanup (disable_thread_events, NULL);
4469 /* Request threads to stop, and then wait for the stops. Because
4470 threads we already know about can spawn more threads while we're
4471 trying to stop them, and we only learn about new threads when we
4472 update the thread list, do this in a loop, and keep iterating
4473 until two passes find no threads that need to be stopped. */
4474 for (pass = 0; pass < 2; pass++, iterations++)
4477 fprintf_unfiltered (gdb_stdlog,
4478 "infrun: stop_all_threads, pass=%d, "
4479 "iterations=%d\n", pass, iterations);
4483 struct target_waitstatus ws;
4485 struct thread_info *t;
4487 update_thread_list ();
4489 /* Go through all threads looking for threads that we need
4490 to tell the target to stop. */
4491 ALL_NON_EXITED_THREADS (t)
4495 /* If already stopping, don't request a stop again.
4496 We just haven't seen the notification yet. */
4497 if (!t->stop_requested)
4500 fprintf_unfiltered (gdb_stdlog,
4501 "infrun: %s executing, "
4503 target_pid_to_str (t->ptid));
4504 target_stop (t->ptid);
4505 t->stop_requested = 1;
4510 fprintf_unfiltered (gdb_stdlog,
4511 "infrun: %s executing, "
4512 "already stopping\n",
4513 target_pid_to_str (t->ptid));
4516 if (t->stop_requested)
4522 fprintf_unfiltered (gdb_stdlog,
4523 "infrun: %s not executing\n",
4524 target_pid_to_str (t->ptid));
4526 /* The thread may be not executing, but still be
4527 resumed with a pending status to process. */
4535 /* If we find new threads on the second iteration, restart
4536 over. We want to see two iterations in a row with all
4541 event_ptid = wait_one (&ws);
4542 if (ws.kind == TARGET_WAITKIND_NO_RESUMED)
4544 /* All resumed threads exited. */
4546 else if (ws.kind == TARGET_WAITKIND_THREAD_EXITED
4547 || ws.kind == TARGET_WAITKIND_EXITED
4548 || ws.kind == TARGET_WAITKIND_SIGNALLED)
4552 ptid_t ptid = pid_to_ptid (ws.value.integer);
4554 fprintf_unfiltered (gdb_stdlog,
4555 "infrun: %s exited while "
4556 "stopping threads\n",
4557 target_pid_to_str (ptid));
4562 struct inferior *inf;
4564 t = find_thread_ptid (event_ptid);
4566 t = add_thread (event_ptid);
4568 t->stop_requested = 0;
4571 t->control.may_range_step = 0;
4573 /* This may be the first time we see the inferior report
4575 inf = find_inferior_ptid (event_ptid);
4576 if (inf->needs_setup)
4578 switch_to_thread_no_regs (t);
4582 if (ws.kind == TARGET_WAITKIND_STOPPED
4583 && ws.value.sig == GDB_SIGNAL_0)
4585 /* We caught the event that we intended to catch, so
4586 there's no event pending. */
4587 t->suspend.waitstatus.kind = TARGET_WAITKIND_IGNORE;
4588 t->suspend.waitstatus_pending_p = 0;
4590 if (displaced_step_fixup (t->ptid, GDB_SIGNAL_0) < 0)
4592 /* Add it back to the step-over queue. */
4595 fprintf_unfiltered (gdb_stdlog,
4596 "infrun: displaced-step of %s "
4597 "canceled: adding back to the "
4598 "step-over queue\n",
4599 target_pid_to_str (t->ptid));
4601 t->control.trap_expected = 0;
4602 thread_step_over_chain_enqueue (t);
4607 enum gdb_signal sig;
4608 struct regcache *regcache;
4609 struct address_space *aspace;
4615 statstr = target_waitstatus_to_string (&ws);
4616 fprintf_unfiltered (gdb_stdlog,
4617 "infrun: target_wait %s, saving "
4618 "status for %d.%ld.%ld\n",
4620 ptid_get_pid (t->ptid),
4621 ptid_get_lwp (t->ptid),
4622 ptid_get_tid (t->ptid));
4626 /* Record for later. */
4627 save_waitstatus (t, &ws);
4629 sig = (ws.kind == TARGET_WAITKIND_STOPPED
4630 ? ws.value.sig : GDB_SIGNAL_0);
4632 if (displaced_step_fixup (t->ptid, sig) < 0)
4634 /* Add it back to the step-over queue. */
4635 t->control.trap_expected = 0;
4636 thread_step_over_chain_enqueue (t);
4639 regcache = get_thread_regcache (t->ptid);
4640 t->suspend.stop_pc = regcache_read_pc (regcache);
4644 fprintf_unfiltered (gdb_stdlog,
4645 "infrun: saved stop_pc=%s for %s "
4646 "(currently_stepping=%d)\n",
4647 paddress (target_gdbarch (),
4648 t->suspend.stop_pc),
4649 target_pid_to_str (t->ptid),
4650 currently_stepping (t));
4657 do_cleanups (old_chain);
4660 fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads done\n");
4663 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4666 handle_no_resumed (struct execution_control_state *ecs)
4668 struct inferior *inf;
4669 struct thread_info *thread;
4671 if (target_can_async_p () && !sync_execution)
4673 /* There were no unwaited-for children left in the target, but,
4674 we're not synchronously waiting for events either. Just
4678 fprintf_unfiltered (gdb_stdlog,
4679 "infrun: TARGET_WAITKIND_NO_RESUMED " "(ignoring: bg)\n");
4680 prepare_to_wait (ecs);
4684 /* Otherwise, if we were running a synchronous execution command, we
4685 may need to cancel it and give the user back the terminal.
4687 In non-stop mode, the target can't tell whether we've already
4688 consumed previous stop events, so it can end up sending us a
4689 no-resumed event like so:
4691 #0 - thread 1 is left stopped
4693 #1 - thread 2 is resumed and hits breakpoint
4694 -> TARGET_WAITKIND_STOPPED
4696 #2 - thread 3 is resumed and exits
4697 this is the last resumed thread, so
4698 -> TARGET_WAITKIND_NO_RESUMED
4700 #3 - gdb processes stop for thread 2 and decides to re-resume
4703 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4704 thread 2 is now resumed, so the event should be ignored.
4706 IOW, if the stop for thread 2 doesn't end a foreground command,
4707 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4708 event. But it could be that the event meant that thread 2 itself
4709 (or whatever other thread was the last resumed thread) exited.
4711 To address this we refresh the thread list and check whether we
4712 have resumed threads _now_. In the example above, this removes
4713 thread 3 from the thread list. If thread 2 was re-resumed, we
4714 ignore this event. If we find no thread resumed, then we cancel
4715 the synchronous command show "no unwaited-for " to the user. */
4716 update_thread_list ();
4718 ALL_NON_EXITED_THREADS (thread)
4720 if (thread->executing
4721 || thread->suspend.waitstatus_pending_p)
4723 /* There were no unwaited-for children left in the target at
4724 some point, but there are now. Just ignore. */
4726 fprintf_unfiltered (gdb_stdlog,
4727 "infrun: TARGET_WAITKIND_NO_RESUMED "
4728 "(ignoring: found resumed)\n");
4729 prepare_to_wait (ecs);
4734 /* Note however that we may find no resumed thread because the whole
4735 process exited meanwhile (thus updating the thread list results
4736 in an empty thread list). In this case we know we'll be getting
4737 a process exit event shortly. */
4743 thread = any_live_thread_of_process (inf->pid);
4747 fprintf_unfiltered (gdb_stdlog,
4748 "infrun: TARGET_WAITKIND_NO_RESUMED "
4749 "(expect process exit)\n");
4750 prepare_to_wait (ecs);
4755 /* Go ahead and report the event. */
4759 /* Given an execution control state that has been freshly filled in by
4760 an event from the inferior, figure out what it means and take
4763 The alternatives are:
4765 1) stop_waiting and return; to really stop and return to the
4768 2) keep_going and return; to wait for the next event (set
4769 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4773 handle_inferior_event_1 (struct execution_control_state *ecs)
4775 enum stop_kind stop_soon;
4777 if (ecs->ws.kind == TARGET_WAITKIND_IGNORE)
4779 /* We had an event in the inferior, but we are not interested in
4780 handling it at this level. The lower layers have already
4781 done what needs to be done, if anything.
4783 One of the possible circumstances for this is when the
4784 inferior produces output for the console. The inferior has
4785 not stopped, and we are ignoring the event. Another possible
4786 circumstance is any event which the lower level knows will be
4787 reported multiple times without an intervening resume. */
4789 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n");
4790 prepare_to_wait (ecs);
4794 if (ecs->ws.kind == TARGET_WAITKIND_THREAD_EXITED)
4797 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4798 prepare_to_wait (ecs);
4802 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED
4803 && handle_no_resumed (ecs))
4806 /* Cache the last pid/waitstatus. */
4807 set_last_target_status (ecs->ptid, ecs->ws);
4809 /* Always clear state belonging to the previous time we stopped. */
4810 stop_stack_dummy = STOP_NONE;
4812 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED)
4814 /* No unwaited-for children left. IOW, all resumed children
4817 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4819 stop_print_frame = 0;
4824 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
4825 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
4827 ecs->event_thread = find_thread_ptid (ecs->ptid);
4828 /* If it's a new thread, add it to the thread database. */
4829 if (ecs->event_thread == NULL)
4830 ecs->event_thread = add_thread (ecs->ptid);
4832 /* Disable range stepping. If the next step request could use a
4833 range, this will be end up re-enabled then. */
4834 ecs->event_thread->control.may_range_step = 0;
4837 /* Dependent on valid ECS->EVENT_THREAD. */
4838 adjust_pc_after_break (ecs->event_thread, &ecs->ws);
4840 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4841 reinit_frame_cache ();
4843 breakpoint_retire_moribund ();
4845 /* First, distinguish signals caused by the debugger from signals
4846 that have to do with the program's own actions. Note that
4847 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4848 on the operating system version. Here we detect when a SIGILL or
4849 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4850 something similar for SIGSEGV, since a SIGSEGV will be generated
4851 when we're trying to execute a breakpoint instruction on a
4852 non-executable stack. This happens for call dummy breakpoints
4853 for architectures like SPARC that place call dummies on the
4855 if (ecs->ws.kind == TARGET_WAITKIND_STOPPED
4856 && (ecs->ws.value.sig == GDB_SIGNAL_ILL
4857 || ecs->ws.value.sig == GDB_SIGNAL_SEGV
4858 || ecs->ws.value.sig == GDB_SIGNAL_EMT))
4860 struct regcache *regcache = get_thread_regcache (ecs->ptid);
4862 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache),
4863 regcache_read_pc (regcache)))
4866 fprintf_unfiltered (gdb_stdlog,
4867 "infrun: Treating signal as SIGTRAP\n");
4868 ecs->ws.value.sig = GDB_SIGNAL_TRAP;
4872 /* Mark the non-executing threads accordingly. In all-stop, all
4873 threads of all processes are stopped when we get any event
4874 reported. In non-stop mode, only the event thread stops. */
4878 if (!target_is_non_stop_p ())
4879 mark_ptid = minus_one_ptid;
4880 else if (ecs->ws.kind == TARGET_WAITKIND_SIGNALLED
4881 || ecs->ws.kind == TARGET_WAITKIND_EXITED)
4883 /* If we're handling a process exit in non-stop mode, even
4884 though threads haven't been deleted yet, one would think
4885 that there is nothing to do, as threads of the dead process
4886 will be soon deleted, and threads of any other process were
4887 left running. However, on some targets, threads survive a
4888 process exit event. E.g., for the "checkpoint" command,
4889 when the current checkpoint/fork exits, linux-fork.c
4890 automatically switches to another fork from within
4891 target_mourn_inferior, by associating the same
4892 inferior/thread to another fork. We haven't mourned yet at
4893 this point, but we must mark any threads left in the
4894 process as not-executing so that finish_thread_state marks
4895 them stopped (in the user's perspective) if/when we present
4896 the stop to the user. */
4897 mark_ptid = pid_to_ptid (ptid_get_pid (ecs->ptid));
4900 mark_ptid = ecs->ptid;
4902 set_executing (mark_ptid, 0);
4904 /* Likewise the resumed flag. */
4905 set_resumed (mark_ptid, 0);
4908 switch (ecs->ws.kind)
4910 case TARGET_WAITKIND_LOADED:
4912 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n");
4913 if (!ptid_equal (ecs->ptid, inferior_ptid))
4914 context_switch (ecs->ptid);
4915 /* Ignore gracefully during startup of the inferior, as it might
4916 be the shell which has just loaded some objects, otherwise
4917 add the symbols for the newly loaded objects. Also ignore at
4918 the beginning of an attach or remote session; we will query
4919 the full list of libraries once the connection is
4922 stop_soon = get_inferior_stop_soon (ecs->ptid);
4923 if (stop_soon == NO_STOP_QUIETLY)
4925 struct regcache *regcache;
4927 regcache = get_thread_regcache (ecs->ptid);
4929 handle_solib_event ();
4931 ecs->event_thread->control.stop_bpstat
4932 = bpstat_stop_status (get_regcache_aspace (regcache),
4933 stop_pc, ecs->ptid, &ecs->ws);
4935 if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
4937 /* A catchpoint triggered. */
4938 process_event_stop_test (ecs);
4942 /* If requested, stop when the dynamic linker notifies
4943 gdb of events. This allows the user to get control
4944 and place breakpoints in initializer routines for
4945 dynamically loaded objects (among other things). */
4946 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
4947 if (stop_on_solib_events)
4949 /* Make sure we print "Stopped due to solib-event" in
4951 stop_print_frame = 1;
4958 /* If we are skipping through a shell, or through shared library
4959 loading that we aren't interested in, resume the program. If
4960 we're running the program normally, also resume. */
4961 if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY)
4963 /* Loading of shared libraries might have changed breakpoint
4964 addresses. Make sure new breakpoints are inserted. */
4965 if (stop_soon == NO_STOP_QUIETLY)
4966 insert_breakpoints ();
4967 resume (GDB_SIGNAL_0);
4968 prepare_to_wait (ecs);
4972 /* But stop if we're attaching or setting up a remote
4974 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
4975 || stop_soon == STOP_QUIETLY_REMOTE)
4978 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
4983 internal_error (__FILE__, __LINE__,
4984 _("unhandled stop_soon: %d"), (int) stop_soon);
4986 case TARGET_WAITKIND_SPURIOUS:
4988 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
4989 if (!ptid_equal (ecs->ptid, inferior_ptid))
4990 context_switch (ecs->ptid);
4991 resume (GDB_SIGNAL_0);
4992 prepare_to_wait (ecs);
4995 case TARGET_WAITKIND_THREAD_CREATED:
4997 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
4998 if (!ptid_equal (ecs->ptid, inferior_ptid))
4999 context_switch (ecs->ptid);
5000 if (!switch_back_to_stepped_thread (ecs))
5004 case TARGET_WAITKIND_EXITED:
5005 case TARGET_WAITKIND_SIGNALLED:
5008 if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
5009 fprintf_unfiltered (gdb_stdlog,
5010 "infrun: TARGET_WAITKIND_EXITED\n");
5012 fprintf_unfiltered (gdb_stdlog,
5013 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5016 inferior_ptid = ecs->ptid;
5017 set_current_inferior (find_inferior_ptid (ecs->ptid));
5018 set_current_program_space (current_inferior ()->pspace);
5019 handle_vfork_child_exec_or_exit (0);
5020 target_terminal_ours (); /* Must do this before mourn anyway. */
5022 /* Clearing any previous state of convenience variables. */
5023 clear_exit_convenience_vars ();
5025 if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
5027 /* Record the exit code in the convenience variable $_exitcode, so
5028 that the user can inspect this again later. */
5029 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5030 (LONGEST) ecs->ws.value.integer);
5032 /* Also record this in the inferior itself. */
5033 current_inferior ()->has_exit_code = 1;
5034 current_inferior ()->exit_code = (LONGEST) ecs->ws.value.integer;
5036 /* Support the --return-child-result option. */
5037 return_child_result_value = ecs->ws.value.integer;
5039 observer_notify_exited (ecs->ws.value.integer);
5043 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5044 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5046 if (gdbarch_gdb_signal_to_target_p (gdbarch))
5048 /* Set the value of the internal variable $_exitsignal,
5049 which holds the signal uncaught by the inferior. */
5050 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5051 gdbarch_gdb_signal_to_target (gdbarch,
5052 ecs->ws.value.sig));
5056 /* We don't have access to the target's method used for
5057 converting between signal numbers (GDB's internal
5058 representation <-> target's representation).
5059 Therefore, we cannot do a good job at displaying this
5060 information to the user. It's better to just warn
5061 her about it (if infrun debugging is enabled), and
5064 fprintf_filtered (gdb_stdlog, _("\
5065 Cannot fill $_exitsignal with the correct signal number.\n"));
5068 observer_notify_signal_exited (ecs->ws.value.sig);
5071 gdb_flush (gdb_stdout);
5072 target_mourn_inferior ();
5073 stop_print_frame = 0;
5077 /* The following are the only cases in which we keep going;
5078 the above cases end in a continue or goto. */
5079 case TARGET_WAITKIND_FORKED:
5080 case TARGET_WAITKIND_VFORKED:
5083 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
5084 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
5086 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_VFORKED\n");
5089 /* Check whether the inferior is displaced stepping. */
5091 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5092 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5094 /* If checking displaced stepping is supported, and thread
5095 ecs->ptid is displaced stepping. */
5096 if (displaced_step_in_progress_thread (ecs->ptid))
5098 struct inferior *parent_inf
5099 = find_inferior_ptid (ecs->ptid);
5100 struct regcache *child_regcache;
5101 CORE_ADDR parent_pc;
5103 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5104 indicating that the displaced stepping of syscall instruction
5105 has been done. Perform cleanup for parent process here. Note
5106 that this operation also cleans up the child process for vfork,
5107 because their pages are shared. */
5108 displaced_step_fixup (ecs->ptid, GDB_SIGNAL_TRAP);
5109 /* Start a new step-over in another thread if there's one
5113 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
5115 struct displaced_step_inferior_state *displaced
5116 = get_displaced_stepping_state (ptid_get_pid (ecs->ptid));
5118 /* Restore scratch pad for child process. */
5119 displaced_step_restore (displaced, ecs->ws.value.related_pid);
5122 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5123 the child's PC is also within the scratchpad. Set the child's PC
5124 to the parent's PC value, which has already been fixed up.
5125 FIXME: we use the parent's aspace here, although we're touching
5126 the child, because the child hasn't been added to the inferior
5127 list yet at this point. */
5130 = get_thread_arch_aspace_regcache (ecs->ws.value.related_pid,
5132 parent_inf->aspace);
5133 /* Read PC value of parent process. */
5134 parent_pc = regcache_read_pc (regcache);
5136 if (debug_displaced)
5137 fprintf_unfiltered (gdb_stdlog,
5138 "displaced: write child pc from %s to %s\n",
5140 regcache_read_pc (child_regcache)),
5141 paddress (gdbarch, parent_pc));
5143 regcache_write_pc (child_regcache, parent_pc);
5147 if (!ptid_equal (ecs->ptid, inferior_ptid))
5148 context_switch (ecs->ptid);
5150 /* Immediately detach breakpoints from the child before there's
5151 any chance of letting the user delete breakpoints from the
5152 breakpoint lists. If we don't do this early, it's easy to
5153 leave left over traps in the child, vis: "break foo; catch
5154 fork; c; <fork>; del; c; <child calls foo>". We only follow
5155 the fork on the last `continue', and by that time the
5156 breakpoint at "foo" is long gone from the breakpoint table.
5157 If we vforked, then we don't need to unpatch here, since both
5158 parent and child are sharing the same memory pages; we'll
5159 need to unpatch at follow/detach time instead to be certain
5160 that new breakpoints added between catchpoint hit time and
5161 vfork follow are detached. */
5162 if (ecs->ws.kind != TARGET_WAITKIND_VFORKED)
5164 /* This won't actually modify the breakpoint list, but will
5165 physically remove the breakpoints from the child. */
5166 detach_breakpoints (ecs->ws.value.related_pid);
5169 delete_just_stopped_threads_single_step_breakpoints ();
5171 /* In case the event is caught by a catchpoint, remember that
5172 the event is to be followed at the next resume of the thread,
5173 and not immediately. */
5174 ecs->event_thread->pending_follow = ecs->ws;
5176 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5178 ecs->event_thread->control.stop_bpstat
5179 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5180 stop_pc, ecs->ptid, &ecs->ws);
5182 /* If no catchpoint triggered for this, then keep going. Note
5183 that we're interested in knowing the bpstat actually causes a
5184 stop, not just if it may explain the signal. Software
5185 watchpoints, for example, always appear in the bpstat. */
5186 if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
5192 = (follow_fork_mode_string == follow_fork_mode_child);
5194 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5196 should_resume = follow_fork ();
5199 child = ecs->ws.value.related_pid;
5201 /* In non-stop mode, also resume the other branch. */
5202 if (!detach_fork && (non_stop
5203 || (sched_multi && target_is_non_stop_p ())))
5206 switch_to_thread (parent);
5208 switch_to_thread (child);
5210 ecs->event_thread = inferior_thread ();
5211 ecs->ptid = inferior_ptid;
5216 switch_to_thread (child);
5218 switch_to_thread (parent);
5220 ecs->event_thread = inferior_thread ();
5221 ecs->ptid = inferior_ptid;
5229 process_event_stop_test (ecs);
5232 case TARGET_WAITKIND_VFORK_DONE:
5233 /* Done with the shared memory region. Re-insert breakpoints in
5234 the parent, and keep going. */
5237 fprintf_unfiltered (gdb_stdlog,
5238 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5240 if (!ptid_equal (ecs->ptid, inferior_ptid))
5241 context_switch (ecs->ptid);
5243 current_inferior ()->waiting_for_vfork_done = 0;
5244 current_inferior ()->pspace->breakpoints_not_allowed = 0;
5245 /* This also takes care of reinserting breakpoints in the
5246 previously locked inferior. */
5250 case TARGET_WAITKIND_EXECD:
5252 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n");
5254 if (!ptid_equal (ecs->ptid, inferior_ptid))
5255 context_switch (ecs->ptid);
5257 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5259 /* Do whatever is necessary to the parent branch of the vfork. */
5260 handle_vfork_child_exec_or_exit (1);
5262 /* This causes the eventpoints and symbol table to be reset.
5263 Must do this now, before trying to determine whether to
5265 follow_exec (inferior_ptid, ecs->ws.value.execd_pathname);
5267 /* In follow_exec we may have deleted the original thread and
5268 created a new one. Make sure that the event thread is the
5269 execd thread for that case (this is a nop otherwise). */
5270 ecs->event_thread = inferior_thread ();
5272 ecs->event_thread->control.stop_bpstat
5273 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5274 stop_pc, ecs->ptid, &ecs->ws);
5276 /* Note that this may be referenced from inside
5277 bpstat_stop_status above, through inferior_has_execd. */
5278 xfree (ecs->ws.value.execd_pathname);
5279 ecs->ws.value.execd_pathname = NULL;
5281 /* If no catchpoint triggered for this, then keep going. */
5282 if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
5284 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5288 process_event_stop_test (ecs);
5291 /* Be careful not to try to gather much state about a thread
5292 that's in a syscall. It's frequently a losing proposition. */
5293 case TARGET_WAITKIND_SYSCALL_ENTRY:
5295 fprintf_unfiltered (gdb_stdlog,
5296 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5297 /* Getting the current syscall number. */
5298 if (handle_syscall_event (ecs) == 0)
5299 process_event_stop_test (ecs);
5302 /* Before examining the threads further, step this thread to
5303 get it entirely out of the syscall. (We get notice of the
5304 event when the thread is just on the verge of exiting a
5305 syscall. Stepping one instruction seems to get it back
5307 case TARGET_WAITKIND_SYSCALL_RETURN:
5309 fprintf_unfiltered (gdb_stdlog,
5310 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5311 if (handle_syscall_event (ecs) == 0)
5312 process_event_stop_test (ecs);
5315 case TARGET_WAITKIND_STOPPED:
5317 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n");
5318 ecs->event_thread->suspend.stop_signal = ecs->ws.value.sig;
5319 handle_signal_stop (ecs);
5322 case TARGET_WAITKIND_NO_HISTORY:
5324 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5325 /* Reverse execution: target ran out of history info. */
5327 /* Switch to the stopped thread. */
5328 if (!ptid_equal (ecs->ptid, inferior_ptid))
5329 context_switch (ecs->ptid);
5331 fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n");
5333 delete_just_stopped_threads_single_step_breakpoints ();
5334 stop_pc = regcache_read_pc (get_thread_regcache (inferior_ptid));
5335 observer_notify_no_history ();
5341 /* A wrapper around handle_inferior_event_1, which also makes sure
5342 that all temporary struct value objects that were created during
5343 the handling of the event get deleted at the end. */
5346 handle_inferior_event (struct execution_control_state *ecs)
5348 struct value *mark = value_mark ();
5350 handle_inferior_event_1 (ecs);
5351 /* Purge all temporary values created during the event handling,
5352 as it could be a long time before we return to the command level
5353 where such values would otherwise be purged. */
5354 value_free_to_mark (mark);
5357 /* Restart threads back to what they were trying to do back when we
5358 paused them for an in-line step-over. The EVENT_THREAD thread is
5362 restart_threads (struct thread_info *event_thread)
5364 struct thread_info *tp;
5365 struct thread_info *step_over = NULL;
5367 /* In case the instruction just stepped spawned a new thread. */
5368 update_thread_list ();
5370 ALL_NON_EXITED_THREADS (tp)
5372 if (tp == event_thread)
5375 fprintf_unfiltered (gdb_stdlog,
5376 "infrun: restart threads: "
5377 "[%s] is event thread\n",
5378 target_pid_to_str (tp->ptid));
5382 if (!(tp->state == THREAD_RUNNING || tp->control.in_infcall))
5385 fprintf_unfiltered (gdb_stdlog,
5386 "infrun: restart threads: "
5387 "[%s] not meant to be running\n",
5388 target_pid_to_str (tp->ptid));
5395 fprintf_unfiltered (gdb_stdlog,
5396 "infrun: restart threads: [%s] resumed\n",
5397 target_pid_to_str (tp->ptid));
5398 gdb_assert (tp->executing || tp->suspend.waitstatus_pending_p);
5402 if (thread_is_in_step_over_chain (tp))
5405 fprintf_unfiltered (gdb_stdlog,
5406 "infrun: restart threads: "
5407 "[%s] needs step-over\n",
5408 target_pid_to_str (tp->ptid));
5409 gdb_assert (!tp->resumed);
5414 if (tp->suspend.waitstatus_pending_p)
5417 fprintf_unfiltered (gdb_stdlog,
5418 "infrun: restart threads: "
5419 "[%s] has pending status\n",
5420 target_pid_to_str (tp->ptid));
5425 /* If some thread needs to start a step-over at this point, it
5426 should still be in the step-over queue, and thus skipped
5428 if (thread_still_needs_step_over (tp))
5430 internal_error (__FILE__, __LINE__,
5431 "thread [%s] needs a step-over, but not in "
5432 "step-over queue\n",
5433 target_pid_to_str (tp->ptid));
5436 if (currently_stepping (tp))
5439 fprintf_unfiltered (gdb_stdlog,
5440 "infrun: restart threads: [%s] was stepping\n",
5441 target_pid_to_str (tp->ptid));
5442 keep_going_stepped_thread (tp);
5446 struct execution_control_state ecss;
5447 struct execution_control_state *ecs = &ecss;
5450 fprintf_unfiltered (gdb_stdlog,
5451 "infrun: restart threads: [%s] continuing\n",
5452 target_pid_to_str (tp->ptid));
5453 reset_ecs (ecs, tp);
5454 switch_to_thread (tp->ptid);
5455 keep_going_pass_signal (ecs);
5460 /* Callback for iterate_over_threads. Find a resumed thread that has
5461 a pending waitstatus. */
5464 resumed_thread_with_pending_status (struct thread_info *tp,
5468 && tp->suspend.waitstatus_pending_p);
5471 /* Called when we get an event that may finish an in-line or
5472 out-of-line (displaced stepping) step-over started previously.
5473 Return true if the event is processed and we should go back to the
5474 event loop; false if the caller should continue processing the
5478 finish_step_over (struct execution_control_state *ecs)
5480 int had_step_over_info;
5482 displaced_step_fixup (ecs->ptid,
5483 ecs->event_thread->suspend.stop_signal);
5485 had_step_over_info = step_over_info_valid_p ();
5487 if (had_step_over_info)
5489 /* If we're stepping over a breakpoint with all threads locked,
5490 then only the thread that was stepped should be reporting
5492 gdb_assert (ecs->event_thread->control.trap_expected);
5494 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
5495 clear_step_over_info ();
5498 if (!target_is_non_stop_p ())
5501 /* Start a new step-over in another thread if there's one that
5505 /* If we were stepping over a breakpoint before, and haven't started
5506 a new in-line step-over sequence, then restart all other threads
5507 (except the event thread). We can't do this in all-stop, as then
5508 e.g., we wouldn't be able to issue any other remote packet until
5509 these other threads stop. */
5510 if (had_step_over_info && !step_over_info_valid_p ())
5512 struct thread_info *pending;
5514 /* If we only have threads with pending statuses, the restart
5515 below won't restart any thread and so nothing re-inserts the
5516 breakpoint we just stepped over. But we need it inserted
5517 when we later process the pending events, otherwise if
5518 another thread has a pending event for this breakpoint too,
5519 we'd discard its event (because the breakpoint that
5520 originally caused the event was no longer inserted). */
5521 context_switch (ecs->ptid);
5522 insert_breakpoints ();
5524 restart_threads (ecs->event_thread);
5526 /* If we have events pending, go through handle_inferior_event
5527 again, picking up a pending event at random. This avoids
5528 thread starvation. */
5530 /* But not if we just stepped over a watchpoint in order to let
5531 the instruction execute so we can evaluate its expression.
5532 The set of watchpoints that triggered is recorded in the
5533 breakpoint objects themselves (see bp->watchpoint_triggered).
5534 If we processed another event first, that other event could
5535 clobber this info. */
5536 if (ecs->event_thread->stepping_over_watchpoint)
5539 pending = iterate_over_threads (resumed_thread_with_pending_status,
5541 if (pending != NULL)
5543 struct thread_info *tp = ecs->event_thread;
5544 struct regcache *regcache;
5548 fprintf_unfiltered (gdb_stdlog,
5549 "infrun: found resumed threads with "
5550 "pending events, saving status\n");
5553 gdb_assert (pending != tp);
5555 /* Record the event thread's event for later. */
5556 save_waitstatus (tp, &ecs->ws);
5557 /* This was cleared early, by handle_inferior_event. Set it
5558 so this pending event is considered by
5562 gdb_assert (!tp->executing);
5564 regcache = get_thread_regcache (tp->ptid);
5565 tp->suspend.stop_pc = regcache_read_pc (regcache);
5569 fprintf_unfiltered (gdb_stdlog,
5570 "infrun: saved stop_pc=%s for %s "
5571 "(currently_stepping=%d)\n",
5572 paddress (target_gdbarch (),
5573 tp->suspend.stop_pc),
5574 target_pid_to_str (tp->ptid),
5575 currently_stepping (tp));
5578 /* This in-line step-over finished; clear this so we won't
5579 start a new one. This is what handle_signal_stop would
5580 do, if we returned false. */
5581 tp->stepping_over_breakpoint = 0;
5583 /* Wake up the event loop again. */
5584 mark_async_event_handler (infrun_async_inferior_event_token);
5586 prepare_to_wait (ecs);
5594 /* Come here when the program has stopped with a signal. */
5597 handle_signal_stop (struct execution_control_state *ecs)
5599 struct frame_info *frame;
5600 struct gdbarch *gdbarch;
5601 int stopped_by_watchpoint;
5602 enum stop_kind stop_soon;
5605 gdb_assert (ecs->ws.kind == TARGET_WAITKIND_STOPPED);
5607 /* Do we need to clean up the state of a thread that has
5608 completed a displaced single-step? (Doing so usually affects
5609 the PC, so do it here, before we set stop_pc.) */
5610 if (finish_step_over (ecs))
5613 /* If we either finished a single-step or hit a breakpoint, but
5614 the user wanted this thread to be stopped, pretend we got a
5615 SIG0 (generic unsignaled stop). */
5616 if (ecs->event_thread->stop_requested
5617 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
5618 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5620 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5624 struct regcache *regcache = get_thread_regcache (ecs->ptid);
5625 struct gdbarch *gdbarch = get_regcache_arch (regcache);
5626 struct cleanup *old_chain = save_inferior_ptid ();
5628 inferior_ptid = ecs->ptid;
5630 fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = %s\n",
5631 paddress (gdbarch, stop_pc));
5632 if (target_stopped_by_watchpoint ())
5636 fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n");
5638 if (target_stopped_data_address (¤t_target, &addr))
5639 fprintf_unfiltered (gdb_stdlog,
5640 "infrun: stopped data address = %s\n",
5641 paddress (gdbarch, addr));
5643 fprintf_unfiltered (gdb_stdlog,
5644 "infrun: (no data address available)\n");
5647 do_cleanups (old_chain);
5650 /* This is originated from start_remote(), start_inferior() and
5651 shared libraries hook functions. */
5652 stop_soon = get_inferior_stop_soon (ecs->ptid);
5653 if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE)
5655 if (!ptid_equal (ecs->ptid, inferior_ptid))
5656 context_switch (ecs->ptid);
5658 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
5659 stop_print_frame = 1;
5664 /* This originates from attach_command(). We need to overwrite
5665 the stop_signal here, because some kernels don't ignore a
5666 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5667 See more comments in inferior.h. On the other hand, if we
5668 get a non-SIGSTOP, report it to the user - assume the backend
5669 will handle the SIGSTOP if it should show up later.
5671 Also consider that the attach is complete when we see a
5672 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5673 target extended-remote report it instead of a SIGSTOP
5674 (e.g. gdbserver). We already rely on SIGTRAP being our
5675 signal, so this is no exception.
5677 Also consider that the attach is complete when we see a
5678 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5679 the target to stop all threads of the inferior, in case the
5680 low level attach operation doesn't stop them implicitly. If
5681 they weren't stopped implicitly, then the stub will report a
5682 GDB_SIGNAL_0, meaning: stopped for no particular reason
5683 other than GDB's request. */
5684 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
5685 && (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_STOP
5686 || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5687 || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_0))
5689 stop_print_frame = 1;
5691 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5695 /* See if something interesting happened to the non-current thread. If
5696 so, then switch to that thread. */
5697 if (!ptid_equal (ecs->ptid, inferior_ptid))
5700 fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n");
5702 context_switch (ecs->ptid);
5704 if (deprecated_context_hook)
5705 deprecated_context_hook (pid_to_thread_id (ecs->ptid));
5708 /* At this point, get hold of the now-current thread's frame. */
5709 frame = get_current_frame ();
5710 gdbarch = get_frame_arch (frame);
5712 /* Pull the single step breakpoints out of the target. */
5713 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
5715 struct regcache *regcache;
5716 struct address_space *aspace;
5719 regcache = get_thread_regcache (ecs->ptid);
5720 aspace = get_regcache_aspace (regcache);
5721 pc = regcache_read_pc (regcache);
5723 /* However, before doing so, if this single-step breakpoint was
5724 actually for another thread, set this thread up for moving
5726 if (!thread_has_single_step_breakpoint_here (ecs->event_thread,
5729 if (single_step_breakpoint_inserted_here_p (aspace, pc))
5733 fprintf_unfiltered (gdb_stdlog,
5734 "infrun: [%s] hit another thread's "
5735 "single-step breakpoint\n",
5736 target_pid_to_str (ecs->ptid));
5738 ecs->hit_singlestep_breakpoint = 1;
5745 fprintf_unfiltered (gdb_stdlog,
5746 "infrun: [%s] hit its "
5747 "single-step breakpoint\n",
5748 target_pid_to_str (ecs->ptid));
5752 delete_just_stopped_threads_single_step_breakpoints ();
5754 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5755 && ecs->event_thread->control.trap_expected
5756 && ecs->event_thread->stepping_over_watchpoint)
5757 stopped_by_watchpoint = 0;
5759 stopped_by_watchpoint = watchpoints_triggered (&ecs->ws);
5761 /* If necessary, step over this watchpoint. We'll be back to display
5763 if (stopped_by_watchpoint
5764 && (target_have_steppable_watchpoint
5765 || gdbarch_have_nonsteppable_watchpoint (gdbarch)))
5767 /* At this point, we are stopped at an instruction which has
5768 attempted to write to a piece of memory under control of
5769 a watchpoint. The instruction hasn't actually executed
5770 yet. If we were to evaluate the watchpoint expression
5771 now, we would get the old value, and therefore no change
5772 would seem to have occurred.
5774 In order to make watchpoints work `right', we really need
5775 to complete the memory write, and then evaluate the
5776 watchpoint expression. We do this by single-stepping the
5779 It may not be necessary to disable the watchpoint to step over
5780 it. For example, the PA can (with some kernel cooperation)
5781 single step over a watchpoint without disabling the watchpoint.
5783 It is far more common to need to disable a watchpoint to step
5784 the inferior over it. If we have non-steppable watchpoints,
5785 we must disable the current watchpoint; it's simplest to
5786 disable all watchpoints.
5788 Any breakpoint at PC must also be stepped over -- if there's
5789 one, it will have already triggered before the watchpoint
5790 triggered, and we either already reported it to the user, or
5791 it didn't cause a stop and we called keep_going. In either
5792 case, if there was a breakpoint at PC, we must be trying to
5794 ecs->event_thread->stepping_over_watchpoint = 1;
5799 ecs->event_thread->stepping_over_breakpoint = 0;
5800 ecs->event_thread->stepping_over_watchpoint = 0;
5801 bpstat_clear (&ecs->event_thread->control.stop_bpstat);
5802 ecs->event_thread->control.stop_step = 0;
5803 stop_print_frame = 1;
5804 stopped_by_random_signal = 0;
5806 /* Hide inlined functions starting here, unless we just performed stepi or
5807 nexti. After stepi and nexti, always show the innermost frame (not any
5808 inline function call sites). */
5809 if (ecs->event_thread->control.step_range_end != 1)
5811 struct address_space *aspace =
5812 get_regcache_aspace (get_thread_regcache (ecs->ptid));
5814 /* skip_inline_frames is expensive, so we avoid it if we can
5815 determine that the address is one where functions cannot have
5816 been inlined. This improves performance with inferiors that
5817 load a lot of shared libraries, because the solib event
5818 breakpoint is defined as the address of a function (i.e. not
5819 inline). Note that we have to check the previous PC as well
5820 as the current one to catch cases when we have just
5821 single-stepped off a breakpoint prior to reinstating it.
5822 Note that we're assuming that the code we single-step to is
5823 not inline, but that's not definitive: there's nothing
5824 preventing the event breakpoint function from containing
5825 inlined code, and the single-step ending up there. If the
5826 user had set a breakpoint on that inlined code, the missing
5827 skip_inline_frames call would break things. Fortunately
5828 that's an extremely unlikely scenario. */
5829 if (!pc_at_non_inline_function (aspace, stop_pc, &ecs->ws)
5830 && !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5831 && ecs->event_thread->control.trap_expected
5832 && pc_at_non_inline_function (aspace,
5833 ecs->event_thread->prev_pc,
5836 skip_inline_frames (ecs->ptid);
5838 /* Re-fetch current thread's frame in case that invalidated
5840 frame = get_current_frame ();
5841 gdbarch = get_frame_arch (frame);
5845 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5846 && ecs->event_thread->control.trap_expected
5847 && gdbarch_single_step_through_delay_p (gdbarch)
5848 && currently_stepping (ecs->event_thread))
5850 /* We're trying to step off a breakpoint. Turns out that we're
5851 also on an instruction that needs to be stepped multiple
5852 times before it's been fully executing. E.g., architectures
5853 with a delay slot. It needs to be stepped twice, once for
5854 the instruction and once for the delay slot. */
5855 int step_through_delay
5856 = gdbarch_single_step_through_delay (gdbarch, frame);
5858 if (debug_infrun && step_through_delay)
5859 fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n");
5860 if (ecs->event_thread->control.step_range_end == 0
5861 && step_through_delay)
5863 /* The user issued a continue when stopped at a breakpoint.
5864 Set up for another trap and get out of here. */
5865 ecs->event_thread->stepping_over_breakpoint = 1;
5869 else if (step_through_delay)
5871 /* The user issued a step when stopped at a breakpoint.
5872 Maybe we should stop, maybe we should not - the delay
5873 slot *might* correspond to a line of source. In any
5874 case, don't decide that here, just set
5875 ecs->stepping_over_breakpoint, making sure we
5876 single-step again before breakpoints are re-inserted. */
5877 ecs->event_thread->stepping_over_breakpoint = 1;
5881 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5882 handles this event. */
5883 ecs->event_thread->control.stop_bpstat
5884 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5885 stop_pc, ecs->ptid, &ecs->ws);
5887 /* Following in case break condition called a
5889 stop_print_frame = 1;
5891 /* This is where we handle "moribund" watchpoints. Unlike
5892 software breakpoints traps, hardware watchpoint traps are
5893 always distinguishable from random traps. If no high-level
5894 watchpoint is associated with the reported stop data address
5895 anymore, then the bpstat does not explain the signal ---
5896 simply make sure to ignore it if `stopped_by_watchpoint' is
5900 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5901 && !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
5903 && stopped_by_watchpoint)
5904 fprintf_unfiltered (gdb_stdlog,
5905 "infrun: no user watchpoint explains "
5906 "watchpoint SIGTRAP, ignoring\n");
5908 /* NOTE: cagney/2003-03-29: These checks for a random signal
5909 at one stage in the past included checks for an inferior
5910 function call's call dummy's return breakpoint. The original
5911 comment, that went with the test, read:
5913 ``End of a stack dummy. Some systems (e.g. Sony news) give
5914 another signal besides SIGTRAP, so check here as well as
5917 If someone ever tries to get call dummys on a
5918 non-executable stack to work (where the target would stop
5919 with something like a SIGSEGV), then those tests might need
5920 to be re-instated. Given, however, that the tests were only
5921 enabled when momentary breakpoints were not being used, I
5922 suspect that it won't be the case.
5924 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5925 be necessary for call dummies on a non-executable stack on
5928 /* See if the breakpoints module can explain the signal. */
5930 = !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
5931 ecs->event_thread->suspend.stop_signal);
5933 /* Maybe this was a trap for a software breakpoint that has since
5935 if (random_signal && target_stopped_by_sw_breakpoint ())
5937 if (program_breakpoint_here_p (gdbarch, stop_pc))
5939 struct regcache *regcache;
5942 /* Re-adjust PC to what the program would see if GDB was not
5944 regcache = get_thread_regcache (ecs->event_thread->ptid);
5945 decr_pc = gdbarch_decr_pc_after_break (gdbarch);
5948 struct cleanup *old_cleanups = make_cleanup (null_cleanup, NULL);
5950 if (record_full_is_used ())
5951 record_full_gdb_operation_disable_set ();
5953 regcache_write_pc (regcache, stop_pc + decr_pc);
5955 do_cleanups (old_cleanups);
5960 /* A delayed software breakpoint event. Ignore the trap. */
5962 fprintf_unfiltered (gdb_stdlog,
5963 "infrun: delayed software breakpoint "
5964 "trap, ignoring\n");
5969 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
5970 has since been removed. */
5971 if (random_signal && target_stopped_by_hw_breakpoint ())
5973 /* A delayed hardware breakpoint event. Ignore the trap. */
5975 fprintf_unfiltered (gdb_stdlog,
5976 "infrun: delayed hardware breakpoint/watchpoint "
5977 "trap, ignoring\n");
5981 /* If not, perhaps stepping/nexting can. */
5983 random_signal = !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5984 && currently_stepping (ecs->event_thread));
5986 /* Perhaps the thread hit a single-step breakpoint of _another_
5987 thread. Single-step breakpoints are transparent to the
5988 breakpoints module. */
5990 random_signal = !ecs->hit_singlestep_breakpoint;
5992 /* No? Perhaps we got a moribund watchpoint. */
5994 random_signal = !stopped_by_watchpoint;
5996 /* For the program's own signals, act according to
5997 the signal handling tables. */
6001 /* Signal not for debugging purposes. */
6002 struct inferior *inf = find_inferior_ptid (ecs->ptid);
6003 enum gdb_signal stop_signal = ecs->event_thread->suspend.stop_signal;
6006 fprintf_unfiltered (gdb_stdlog, "infrun: random signal (%s)\n",
6007 gdb_signal_to_symbol_string (stop_signal));
6009 stopped_by_random_signal = 1;
6011 /* Always stop on signals if we're either just gaining control
6012 of the program, or the user explicitly requested this thread
6013 to remain stopped. */
6014 if (stop_soon != NO_STOP_QUIETLY
6015 || ecs->event_thread->stop_requested
6017 && signal_stop_state (ecs->event_thread->suspend.stop_signal)))
6023 /* Notify observers the signal has "handle print" set. Note we
6024 returned early above if stopping; normal_stop handles the
6025 printing in that case. */
6026 if (signal_print[ecs->event_thread->suspend.stop_signal])
6028 /* The signal table tells us to print about this signal. */
6029 target_terminal_ours_for_output ();
6030 observer_notify_signal_received (ecs->event_thread->suspend.stop_signal);
6031 target_terminal_inferior ();
6034 /* Clear the signal if it should not be passed. */
6035 if (signal_program[ecs->event_thread->suspend.stop_signal] == 0)
6036 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
6038 if (ecs->event_thread->prev_pc == stop_pc
6039 && ecs->event_thread->control.trap_expected
6040 && ecs->event_thread->control.step_resume_breakpoint == NULL)
6044 /* We were just starting a new sequence, attempting to
6045 single-step off of a breakpoint and expecting a SIGTRAP.
6046 Instead this signal arrives. This signal will take us out
6047 of the stepping range so GDB needs to remember to, when
6048 the signal handler returns, resume stepping off that
6050 /* To simplify things, "continue" is forced to use the same
6051 code paths as single-step - set a breakpoint at the
6052 signal return address and then, once hit, step off that
6055 fprintf_unfiltered (gdb_stdlog,
6056 "infrun: signal arrived while stepping over "
6059 was_in_line = step_over_info_valid_p ();
6060 clear_step_over_info ();
6061 insert_hp_step_resume_breakpoint_at_frame (frame);
6062 ecs->event_thread->step_after_step_resume_breakpoint = 1;
6063 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6064 ecs->event_thread->control.trap_expected = 0;
6066 if (target_is_non_stop_p ())
6068 /* Either "set non-stop" is "on", or the target is
6069 always in non-stop mode. In this case, we have a bit
6070 more work to do. Resume the current thread, and if
6071 we had paused all threads, restart them while the
6072 signal handler runs. */
6077 restart_threads (ecs->event_thread);
6079 else if (debug_infrun)
6081 fprintf_unfiltered (gdb_stdlog,
6082 "infrun: no need to restart threads\n");
6087 /* If we were nexting/stepping some other thread, switch to
6088 it, so that we don't continue it, losing control. */
6089 if (!switch_back_to_stepped_thread (ecs))
6094 if (ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_0
6095 && (pc_in_thread_step_range (stop_pc, ecs->event_thread)
6096 || ecs->event_thread->control.step_range_end == 1)
6097 && frame_id_eq (get_stack_frame_id (frame),
6098 ecs->event_thread->control.step_stack_frame_id)
6099 && ecs->event_thread->control.step_resume_breakpoint == NULL)
6101 /* The inferior is about to take a signal that will take it
6102 out of the single step range. Set a breakpoint at the
6103 current PC (which is presumably where the signal handler
6104 will eventually return) and then allow the inferior to
6107 Note that this is only needed for a signal delivered
6108 while in the single-step range. Nested signals aren't a
6109 problem as they eventually all return. */
6111 fprintf_unfiltered (gdb_stdlog,
6112 "infrun: signal may take us out of "
6113 "single-step range\n");
6115 clear_step_over_info ();
6116 insert_hp_step_resume_breakpoint_at_frame (frame);
6117 ecs->event_thread->step_after_step_resume_breakpoint = 1;
6118 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6119 ecs->event_thread->control.trap_expected = 0;
6124 /* Note: step_resume_breakpoint may be non-NULL. This occures
6125 when either there's a nested signal, or when there's a
6126 pending signal enabled just as the signal handler returns
6127 (leaving the inferior at the step-resume-breakpoint without
6128 actually executing it). Either way continue until the
6129 breakpoint is really hit. */
6131 if (!switch_back_to_stepped_thread (ecs))
6134 fprintf_unfiltered (gdb_stdlog,
6135 "infrun: random signal, keep going\n");
6142 process_event_stop_test (ecs);
6145 /* Come here when we've got some debug event / signal we can explain
6146 (IOW, not a random signal), and test whether it should cause a
6147 stop, or whether we should resume the inferior (transparently).
6148 E.g., could be a breakpoint whose condition evaluates false; we
6149 could be still stepping within the line; etc. */
6152 process_event_stop_test (struct execution_control_state *ecs)
6154 struct symtab_and_line stop_pc_sal;
6155 struct frame_info *frame;
6156 struct gdbarch *gdbarch;
6157 CORE_ADDR jmp_buf_pc;
6158 struct bpstat_what what;
6160 /* Handle cases caused by hitting a breakpoint. */
6162 frame = get_current_frame ();
6163 gdbarch = get_frame_arch (frame);
6165 what = bpstat_what (ecs->event_thread->control.stop_bpstat);
6167 if (what.call_dummy)
6169 stop_stack_dummy = what.call_dummy;
6172 /* A few breakpoint types have callbacks associated (e.g.,
6173 bp_jit_event). Run them now. */
6174 bpstat_run_callbacks (ecs->event_thread->control.stop_bpstat);
6176 /* If we hit an internal event that triggers symbol changes, the
6177 current frame will be invalidated within bpstat_what (e.g., if we
6178 hit an internal solib event). Re-fetch it. */
6179 frame = get_current_frame ();
6180 gdbarch = get_frame_arch (frame);
6182 switch (what.main_action)
6184 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
6185 /* If we hit the breakpoint at longjmp while stepping, we
6186 install a momentary breakpoint at the target of the
6190 fprintf_unfiltered (gdb_stdlog,
6191 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6193 ecs->event_thread->stepping_over_breakpoint = 1;
6195 if (what.is_longjmp)
6197 struct value *arg_value;
6199 /* If we set the longjmp breakpoint via a SystemTap probe,
6200 then use it to extract the arguments. The destination PC
6201 is the third argument to the probe. */
6202 arg_value = probe_safe_evaluate_at_pc (frame, 2);
6205 jmp_buf_pc = value_as_address (arg_value);
6206 jmp_buf_pc = gdbarch_addr_bits_remove (gdbarch, jmp_buf_pc);
6208 else if (!gdbarch_get_longjmp_target_p (gdbarch)
6209 || !gdbarch_get_longjmp_target (gdbarch,
6210 frame, &jmp_buf_pc))
6213 fprintf_unfiltered (gdb_stdlog,
6214 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6215 "(!gdbarch_get_longjmp_target)\n");
6220 /* Insert a breakpoint at resume address. */
6221 insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc);
6224 check_exception_resume (ecs, frame);
6228 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
6230 struct frame_info *init_frame;
6232 /* There are several cases to consider.
6234 1. The initiating frame no longer exists. In this case we
6235 must stop, because the exception or longjmp has gone too
6238 2. The initiating frame exists, and is the same as the
6239 current frame. We stop, because the exception or longjmp
6242 3. The initiating frame exists and is different from the
6243 current frame. This means the exception or longjmp has
6244 been caught beneath the initiating frame, so keep going.
6246 4. longjmp breakpoint has been placed just to protect
6247 against stale dummy frames and user is not interested in
6248 stopping around longjmps. */
6251 fprintf_unfiltered (gdb_stdlog,
6252 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6254 gdb_assert (ecs->event_thread->control.exception_resume_breakpoint
6256 delete_exception_resume_breakpoint (ecs->event_thread);
6258 if (what.is_longjmp)
6260 check_longjmp_breakpoint_for_call_dummy (ecs->event_thread);
6262 if (!frame_id_p (ecs->event_thread->initiating_frame))
6270 init_frame = frame_find_by_id (ecs->event_thread->initiating_frame);
6274 struct frame_id current_id
6275 = get_frame_id (get_current_frame ());
6276 if (frame_id_eq (current_id,
6277 ecs->event_thread->initiating_frame))
6279 /* Case 2. Fall through. */
6289 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6291 delete_step_resume_breakpoint (ecs->event_thread);
6293 end_stepping_range (ecs);
6297 case BPSTAT_WHAT_SINGLE:
6299 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
6300 ecs->event_thread->stepping_over_breakpoint = 1;
6301 /* Still need to check other stuff, at least the case where we
6302 are stepping and step out of the right range. */
6305 case BPSTAT_WHAT_STEP_RESUME:
6307 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6309 delete_step_resume_breakpoint (ecs->event_thread);
6310 if (ecs->event_thread->control.proceed_to_finish
6311 && execution_direction == EXEC_REVERSE)
6313 struct thread_info *tp = ecs->event_thread;
6315 /* We are finishing a function in reverse, and just hit the
6316 step-resume breakpoint at the start address of the
6317 function, and we're almost there -- just need to back up
6318 by one more single-step, which should take us back to the
6320 tp->control.step_range_start = tp->control.step_range_end = 1;
6324 fill_in_stop_func (gdbarch, ecs);
6325 if (stop_pc == ecs->stop_func_start
6326 && execution_direction == EXEC_REVERSE)
6328 /* We are stepping over a function call in reverse, and just
6329 hit the step-resume breakpoint at the start address of
6330 the function. Go back to single-stepping, which should
6331 take us back to the function call. */
6332 ecs->event_thread->stepping_over_breakpoint = 1;
6338 case BPSTAT_WHAT_STOP_NOISY:
6340 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6341 stop_print_frame = 1;
6343 /* Assume the thread stopped for a breapoint. We'll still check
6344 whether a/the breakpoint is there when the thread is next
6346 ecs->event_thread->stepping_over_breakpoint = 1;
6351 case BPSTAT_WHAT_STOP_SILENT:
6353 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6354 stop_print_frame = 0;
6356 /* Assume the thread stopped for a breapoint. We'll still check
6357 whether a/the breakpoint is there when the thread is next
6359 ecs->event_thread->stepping_over_breakpoint = 1;
6363 case BPSTAT_WHAT_HP_STEP_RESUME:
6365 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6367 delete_step_resume_breakpoint (ecs->event_thread);
6368 if (ecs->event_thread->step_after_step_resume_breakpoint)
6370 /* Back when the step-resume breakpoint was inserted, we
6371 were trying to single-step off a breakpoint. Go back to
6373 ecs->event_thread->step_after_step_resume_breakpoint = 0;
6374 ecs->event_thread->stepping_over_breakpoint = 1;
6380 case BPSTAT_WHAT_KEEP_CHECKING:
6384 /* If we stepped a permanent breakpoint and we had a high priority
6385 step-resume breakpoint for the address we stepped, but we didn't
6386 hit it, then we must have stepped into the signal handler. The
6387 step-resume was only necessary to catch the case of _not_
6388 stepping into the handler, so delete it, and fall through to
6389 checking whether the step finished. */
6390 if (ecs->event_thread->stepped_breakpoint)
6392 struct breakpoint *sr_bp
6393 = ecs->event_thread->control.step_resume_breakpoint;
6396 && sr_bp->loc->permanent
6397 && sr_bp->type == bp_hp_step_resume
6398 && sr_bp->loc->address == ecs->event_thread->prev_pc)
6401 fprintf_unfiltered (gdb_stdlog,
6402 "infrun: stepped permanent breakpoint, stopped in "
6404 delete_step_resume_breakpoint (ecs->event_thread);
6405 ecs->event_thread->step_after_step_resume_breakpoint = 0;
6409 /* We come here if we hit a breakpoint but should not stop for it.
6410 Possibly we also were stepping and should stop for that. So fall
6411 through and test for stepping. But, if not stepping, do not
6414 /* In all-stop mode, if we're currently stepping but have stopped in
6415 some other thread, we need to switch back to the stepped thread. */
6416 if (switch_back_to_stepped_thread (ecs))
6419 if (ecs->event_thread->control.step_resume_breakpoint)
6422 fprintf_unfiltered (gdb_stdlog,
6423 "infrun: step-resume breakpoint is inserted\n");
6425 /* Having a step-resume breakpoint overrides anything
6426 else having to do with stepping commands until
6427 that breakpoint is reached. */
6432 if (ecs->event_thread->control.step_range_end == 0)
6435 fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n");
6436 /* Likewise if we aren't even stepping. */
6441 /* Re-fetch current thread's frame in case the code above caused
6442 the frame cache to be re-initialized, making our FRAME variable
6443 a dangling pointer. */
6444 frame = get_current_frame ();
6445 gdbarch = get_frame_arch (frame);
6446 fill_in_stop_func (gdbarch, ecs);
6448 /* If stepping through a line, keep going if still within it.
6450 Note that step_range_end is the address of the first instruction
6451 beyond the step range, and NOT the address of the last instruction
6454 Note also that during reverse execution, we may be stepping
6455 through a function epilogue and therefore must detect when
6456 the current-frame changes in the middle of a line. */
6458 if (pc_in_thread_step_range (stop_pc, ecs->event_thread)
6459 && (execution_direction != EXEC_REVERSE
6460 || frame_id_eq (get_frame_id (frame),
6461 ecs->event_thread->control.step_frame_id)))
6465 (gdb_stdlog, "infrun: stepping inside range [%s-%s]\n",
6466 paddress (gdbarch, ecs->event_thread->control.step_range_start),
6467 paddress (gdbarch, ecs->event_thread->control.step_range_end));
6469 /* Tentatively re-enable range stepping; `resume' disables it if
6470 necessary (e.g., if we're stepping over a breakpoint or we
6471 have software watchpoints). */
6472 ecs->event_thread->control.may_range_step = 1;
6474 /* When stepping backward, stop at beginning of line range
6475 (unless it's the function entry point, in which case
6476 keep going back to the call point). */
6477 if (stop_pc == ecs->event_thread->control.step_range_start
6478 && stop_pc != ecs->stop_func_start
6479 && execution_direction == EXEC_REVERSE)
6480 end_stepping_range (ecs);
6487 /* We stepped out of the stepping range. */
6489 /* If we are stepping at the source level and entered the runtime
6490 loader dynamic symbol resolution code...
6492 EXEC_FORWARD: we keep on single stepping until we exit the run
6493 time loader code and reach the callee's address.
6495 EXEC_REVERSE: we've already executed the callee (backward), and
6496 the runtime loader code is handled just like any other
6497 undebuggable function call. Now we need only keep stepping
6498 backward through the trampoline code, and that's handled further
6499 down, so there is nothing for us to do here. */
6501 if (execution_direction != EXEC_REVERSE
6502 && ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6503 && in_solib_dynsym_resolve_code (stop_pc))
6505 CORE_ADDR pc_after_resolver =
6506 gdbarch_skip_solib_resolver (gdbarch, stop_pc);
6509 fprintf_unfiltered (gdb_stdlog,
6510 "infrun: stepped into dynsym resolve code\n");
6512 if (pc_after_resolver)
6514 /* Set up a step-resume breakpoint at the address
6515 indicated by SKIP_SOLIB_RESOLVER. */
6516 struct symtab_and_line sr_sal;
6519 sr_sal.pc = pc_after_resolver;
6520 sr_sal.pspace = get_frame_program_space (frame);
6522 insert_step_resume_breakpoint_at_sal (gdbarch,
6523 sr_sal, null_frame_id);
6530 if (ecs->event_thread->control.step_range_end != 1
6531 && (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6532 || ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
6533 && get_frame_type (frame) == SIGTRAMP_FRAME)
6536 fprintf_unfiltered (gdb_stdlog,
6537 "infrun: stepped into signal trampoline\n");
6538 /* The inferior, while doing a "step" or "next", has ended up in
6539 a signal trampoline (either by a signal being delivered or by
6540 the signal handler returning). Just single-step until the
6541 inferior leaves the trampoline (either by calling the handler
6547 /* If we're in the return path from a shared library trampoline,
6548 we want to proceed through the trampoline when stepping. */
6549 /* macro/2012-04-25: This needs to come before the subroutine
6550 call check below as on some targets return trampolines look
6551 like subroutine calls (MIPS16 return thunks). */
6552 if (gdbarch_in_solib_return_trampoline (gdbarch,
6553 stop_pc, ecs->stop_func_name)
6554 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
6556 /* Determine where this trampoline returns. */
6557 CORE_ADDR real_stop_pc;
6559 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
6562 fprintf_unfiltered (gdb_stdlog,
6563 "infrun: stepped into solib return tramp\n");
6565 /* Only proceed through if we know where it's going. */
6568 /* And put the step-breakpoint there and go until there. */
6569 struct symtab_and_line sr_sal;
6571 init_sal (&sr_sal); /* initialize to zeroes */
6572 sr_sal.pc = real_stop_pc;
6573 sr_sal.section = find_pc_overlay (sr_sal.pc);
6574 sr_sal.pspace = get_frame_program_space (frame);
6576 /* Do not specify what the fp should be when we stop since
6577 on some machines the prologue is where the new fp value
6579 insert_step_resume_breakpoint_at_sal (gdbarch,
6580 sr_sal, null_frame_id);
6582 /* Restart without fiddling with the step ranges or
6589 /* Check for subroutine calls. The check for the current frame
6590 equalling the step ID is not necessary - the check of the
6591 previous frame's ID is sufficient - but it is a common case and
6592 cheaper than checking the previous frame's ID.
6594 NOTE: frame_id_eq will never report two invalid frame IDs as
6595 being equal, so to get into this block, both the current and
6596 previous frame must have valid frame IDs. */
6597 /* The outer_frame_id check is a heuristic to detect stepping
6598 through startup code. If we step over an instruction which
6599 sets the stack pointer from an invalid value to a valid value,
6600 we may detect that as a subroutine call from the mythical
6601 "outermost" function. This could be fixed by marking
6602 outermost frames as !stack_p,code_p,special_p. Then the
6603 initial outermost frame, before sp was valid, would
6604 have code_addr == &_start. See the comment in frame_id_eq
6606 if (!frame_id_eq (get_stack_frame_id (frame),
6607 ecs->event_thread->control.step_stack_frame_id)
6608 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6609 ecs->event_thread->control.step_stack_frame_id)
6610 && (!frame_id_eq (ecs->event_thread->control.step_stack_frame_id,
6612 || (ecs->event_thread->control.step_start_function
6613 != find_pc_function (stop_pc)))))
6615 CORE_ADDR real_stop_pc;
6618 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n");
6620 if (ecs->event_thread->control.step_over_calls == STEP_OVER_NONE)
6622 /* I presume that step_over_calls is only 0 when we're
6623 supposed to be stepping at the assembly language level
6624 ("stepi"). Just stop. */
6625 /* And this works the same backward as frontward. MVS */
6626 end_stepping_range (ecs);
6630 /* Reverse stepping through solib trampolines. */
6632 if (execution_direction == EXEC_REVERSE
6633 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE
6634 && (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
6635 || (ecs->stop_func_start == 0
6636 && in_solib_dynsym_resolve_code (stop_pc))))
6638 /* Any solib trampoline code can be handled in reverse
6639 by simply continuing to single-step. We have already
6640 executed the solib function (backwards), and a few
6641 steps will take us back through the trampoline to the
6647 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
6649 /* We're doing a "next".
6651 Normal (forward) execution: set a breakpoint at the
6652 callee's return address (the address at which the caller
6655 Reverse (backward) execution. set the step-resume
6656 breakpoint at the start of the function that we just
6657 stepped into (backwards), and continue to there. When we
6658 get there, we'll need to single-step back to the caller. */
6660 if (execution_direction == EXEC_REVERSE)
6662 /* If we're already at the start of the function, we've either
6663 just stepped backward into a single instruction function,
6664 or stepped back out of a signal handler to the first instruction
6665 of the function. Just keep going, which will single-step back
6667 if (ecs->stop_func_start != stop_pc && ecs->stop_func_start != 0)
6669 struct symtab_and_line sr_sal;
6671 /* Normal function call return (static or dynamic). */
6673 sr_sal.pc = ecs->stop_func_start;
6674 sr_sal.pspace = get_frame_program_space (frame);
6675 insert_step_resume_breakpoint_at_sal (gdbarch,
6676 sr_sal, null_frame_id);
6680 insert_step_resume_breakpoint_at_caller (frame);
6686 /* If we are in a function call trampoline (a stub between the
6687 calling routine and the real function), locate the real
6688 function. That's what tells us (a) whether we want to step
6689 into it at all, and (b) what prologue we want to run to the
6690 end of, if we do step into it. */
6691 real_stop_pc = skip_language_trampoline (frame, stop_pc);
6692 if (real_stop_pc == 0)
6693 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
6694 if (real_stop_pc != 0)
6695 ecs->stop_func_start = real_stop_pc;
6697 if (real_stop_pc != 0 && in_solib_dynsym_resolve_code (real_stop_pc))
6699 struct symtab_and_line sr_sal;
6702 sr_sal.pc = ecs->stop_func_start;
6703 sr_sal.pspace = get_frame_program_space (frame);
6705 insert_step_resume_breakpoint_at_sal (gdbarch,
6706 sr_sal, null_frame_id);
6711 /* If we have line number information for the function we are
6712 thinking of stepping into and the function isn't on the skip
6715 If there are several symtabs at that PC (e.g. with include
6716 files), just want to know whether *any* of them have line
6717 numbers. find_pc_line handles this. */
6719 struct symtab_and_line tmp_sal;
6721 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
6722 if (tmp_sal.line != 0
6723 && !function_name_is_marked_for_skip (ecs->stop_func_name,
6726 if (execution_direction == EXEC_REVERSE)
6727 handle_step_into_function_backward (gdbarch, ecs);
6729 handle_step_into_function (gdbarch, ecs);
6734 /* If we have no line number and the step-stop-if-no-debug is
6735 set, we stop the step so that the user has a chance to switch
6736 in assembly mode. */
6737 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6738 && step_stop_if_no_debug)
6740 end_stepping_range (ecs);
6744 if (execution_direction == EXEC_REVERSE)
6746 /* If we're already at the start of the function, we've either just
6747 stepped backward into a single instruction function without line
6748 number info, or stepped back out of a signal handler to the first
6749 instruction of the function without line number info. Just keep
6750 going, which will single-step back to the caller. */
6751 if (ecs->stop_func_start != stop_pc)
6753 /* Set a breakpoint at callee's start address.
6754 From there we can step once and be back in the caller. */
6755 struct symtab_and_line sr_sal;
6758 sr_sal.pc = ecs->stop_func_start;
6759 sr_sal.pspace = get_frame_program_space (frame);
6760 insert_step_resume_breakpoint_at_sal (gdbarch,
6761 sr_sal, null_frame_id);
6765 /* Set a breakpoint at callee's return address (the address
6766 at which the caller will resume). */
6767 insert_step_resume_breakpoint_at_caller (frame);
6773 /* Reverse stepping through solib trampolines. */
6775 if (execution_direction == EXEC_REVERSE
6776 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
6778 if (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
6779 || (ecs->stop_func_start == 0
6780 && in_solib_dynsym_resolve_code (stop_pc)))
6782 /* Any solib trampoline code can be handled in reverse
6783 by simply continuing to single-step. We have already
6784 executed the solib function (backwards), and a few
6785 steps will take us back through the trampoline to the
6790 else if (in_solib_dynsym_resolve_code (stop_pc))
6792 /* Stepped backward into the solib dynsym resolver.
6793 Set a breakpoint at its start and continue, then
6794 one more step will take us out. */
6795 struct symtab_and_line sr_sal;
6798 sr_sal.pc = ecs->stop_func_start;
6799 sr_sal.pspace = get_frame_program_space (frame);
6800 insert_step_resume_breakpoint_at_sal (gdbarch,
6801 sr_sal, null_frame_id);
6807 stop_pc_sal = find_pc_line (stop_pc, 0);
6809 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6810 the trampoline processing logic, however, there are some trampolines
6811 that have no names, so we should do trampoline handling first. */
6812 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
6813 && ecs->stop_func_name == NULL
6814 && stop_pc_sal.line == 0)
6817 fprintf_unfiltered (gdb_stdlog,
6818 "infrun: stepped into undebuggable function\n");
6820 /* The inferior just stepped into, or returned to, an
6821 undebuggable function (where there is no debugging information
6822 and no line number corresponding to the address where the
6823 inferior stopped). Since we want to skip this kind of code,
6824 we keep going until the inferior returns from this
6825 function - unless the user has asked us not to (via
6826 set step-mode) or we no longer know how to get back
6827 to the call site. */
6828 if (step_stop_if_no_debug
6829 || !frame_id_p (frame_unwind_caller_id (frame)))
6831 /* If we have no line number and the step-stop-if-no-debug
6832 is set, we stop the step so that the user has a chance to
6833 switch in assembly mode. */
6834 end_stepping_range (ecs);
6839 /* Set a breakpoint at callee's return address (the address
6840 at which the caller will resume). */
6841 insert_step_resume_breakpoint_at_caller (frame);
6847 if (ecs->event_thread->control.step_range_end == 1)
6849 /* It is stepi or nexti. We always want to stop stepping after
6852 fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
6853 end_stepping_range (ecs);
6857 if (stop_pc_sal.line == 0)
6859 /* We have no line number information. That means to stop
6860 stepping (does this always happen right after one instruction,
6861 when we do "s" in a function with no line numbers,
6862 or can this happen as a result of a return or longjmp?). */
6864 fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n");
6865 end_stepping_range (ecs);
6869 /* Look for "calls" to inlined functions, part one. If the inline
6870 frame machinery detected some skipped call sites, we have entered
6871 a new inline function. */
6873 if (frame_id_eq (get_frame_id (get_current_frame ()),
6874 ecs->event_thread->control.step_frame_id)
6875 && inline_skipped_frames (ecs->ptid))
6877 struct symtab_and_line call_sal;
6880 fprintf_unfiltered (gdb_stdlog,
6881 "infrun: stepped into inlined function\n");
6883 find_frame_sal (get_current_frame (), &call_sal);
6885 if (ecs->event_thread->control.step_over_calls != STEP_OVER_ALL)
6887 /* For "step", we're going to stop. But if the call site
6888 for this inlined function is on the same source line as
6889 we were previously stepping, go down into the function
6890 first. Otherwise stop at the call site. */
6892 if (call_sal.line == ecs->event_thread->current_line
6893 && call_sal.symtab == ecs->event_thread->current_symtab)
6894 step_into_inline_frame (ecs->ptid);
6896 end_stepping_range (ecs);
6901 /* For "next", we should stop at the call site if it is on a
6902 different source line. Otherwise continue through the
6903 inlined function. */
6904 if (call_sal.line == ecs->event_thread->current_line
6905 && call_sal.symtab == ecs->event_thread->current_symtab)
6908 end_stepping_range (ecs);
6913 /* Look for "calls" to inlined functions, part two. If we are still
6914 in the same real function we were stepping through, but we have
6915 to go further up to find the exact frame ID, we are stepping
6916 through a more inlined call beyond its call site. */
6918 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6919 && !frame_id_eq (get_frame_id (get_current_frame ()),
6920 ecs->event_thread->control.step_frame_id)
6921 && stepped_in_from (get_current_frame (),
6922 ecs->event_thread->control.step_frame_id))
6925 fprintf_unfiltered (gdb_stdlog,
6926 "infrun: stepping through inlined function\n");
6928 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
6931 end_stepping_range (ecs);
6935 if ((stop_pc == stop_pc_sal.pc)
6936 && (ecs->event_thread->current_line != stop_pc_sal.line
6937 || ecs->event_thread->current_symtab != stop_pc_sal.symtab))
6939 /* We are at the start of a different line. So stop. Note that
6940 we don't stop if we step into the middle of a different line.
6941 That is said to make things like for (;;) statements work
6944 fprintf_unfiltered (gdb_stdlog,
6945 "infrun: stepped to a different line\n");
6946 end_stepping_range (ecs);
6950 /* We aren't done stepping.
6952 Optimize by setting the stepping range to the line.
6953 (We might not be in the original line, but if we entered a
6954 new line in mid-statement, we continue stepping. This makes
6955 things like for(;;) statements work better.) */
6957 ecs->event_thread->control.step_range_start = stop_pc_sal.pc;
6958 ecs->event_thread->control.step_range_end = stop_pc_sal.end;
6959 ecs->event_thread->control.may_range_step = 1;
6960 set_step_info (frame, stop_pc_sal);
6963 fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n");
6967 /* In all-stop mode, if we're currently stepping but have stopped in
6968 some other thread, we may need to switch back to the stepped
6969 thread. Returns true we set the inferior running, false if we left
6970 it stopped (and the event needs further processing). */
6973 switch_back_to_stepped_thread (struct execution_control_state *ecs)
6975 if (!target_is_non_stop_p ())
6977 struct thread_info *tp;
6978 struct thread_info *stepping_thread;
6980 /* If any thread is blocked on some internal breakpoint, and we
6981 simply need to step over that breakpoint to get it going
6982 again, do that first. */
6984 /* However, if we see an event for the stepping thread, then we
6985 know all other threads have been moved past their breakpoints
6986 already. Let the caller check whether the step is finished,
6987 etc., before deciding to move it past a breakpoint. */
6988 if (ecs->event_thread->control.step_range_end != 0)
6991 /* Check if the current thread is blocked on an incomplete
6992 step-over, interrupted by a random signal. */
6993 if (ecs->event_thread->control.trap_expected
6994 && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_TRAP)
6998 fprintf_unfiltered (gdb_stdlog,
6999 "infrun: need to finish step-over of [%s]\n",
7000 target_pid_to_str (ecs->event_thread->ptid));
7006 /* Check if the current thread is blocked by a single-step
7007 breakpoint of another thread. */
7008 if (ecs->hit_singlestep_breakpoint)
7012 fprintf_unfiltered (gdb_stdlog,
7013 "infrun: need to step [%s] over single-step "
7015 target_pid_to_str (ecs->ptid));
7021 /* If this thread needs yet another step-over (e.g., stepping
7022 through a delay slot), do it first before moving on to
7024 if (thread_still_needs_step_over (ecs->event_thread))
7028 fprintf_unfiltered (gdb_stdlog,
7029 "infrun: thread [%s] still needs step-over\n",
7030 target_pid_to_str (ecs->event_thread->ptid));
7036 /* If scheduler locking applies even if not stepping, there's no
7037 need to walk over threads. Above we've checked whether the
7038 current thread is stepping. If some other thread not the
7039 event thread is stepping, then it must be that scheduler
7040 locking is not in effect. */
7041 if (schedlock_applies (ecs->event_thread))
7044 /* Otherwise, we no longer expect a trap in the current thread.
7045 Clear the trap_expected flag before switching back -- this is
7046 what keep_going does as well, if we call it. */
7047 ecs->event_thread->control.trap_expected = 0;
7049 /* Likewise, clear the signal if it should not be passed. */
7050 if (!signal_program[ecs->event_thread->suspend.stop_signal])
7051 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
7053 /* Do all pending step-overs before actually proceeding with
7055 if (start_step_over ())
7057 prepare_to_wait (ecs);
7061 /* Look for the stepping/nexting thread. */
7062 stepping_thread = NULL;
7064 ALL_NON_EXITED_THREADS (tp)
7066 /* Ignore threads of processes the caller is not
7069 && ptid_get_pid (tp->ptid) != ptid_get_pid (ecs->ptid))
7072 /* When stepping over a breakpoint, we lock all threads
7073 except the one that needs to move past the breakpoint.
7074 If a non-event thread has this set, the "incomplete
7075 step-over" check above should have caught it earlier. */
7076 if (tp->control.trap_expected)
7078 internal_error (__FILE__, __LINE__,
7079 "[%s] has inconsistent state: "
7080 "trap_expected=%d\n",
7081 target_pid_to_str (tp->ptid),
7082 tp->control.trap_expected);
7085 /* Did we find the stepping thread? */
7086 if (tp->control.step_range_end)
7088 /* Yep. There should only one though. */
7089 gdb_assert (stepping_thread == NULL);
7091 /* The event thread is handled at the top, before we
7093 gdb_assert (tp != ecs->event_thread);
7095 /* If some thread other than the event thread is
7096 stepping, then scheduler locking can't be in effect,
7097 otherwise we wouldn't have resumed the current event
7098 thread in the first place. */
7099 gdb_assert (!schedlock_applies (tp));
7101 stepping_thread = tp;
7105 if (stepping_thread != NULL)
7108 fprintf_unfiltered (gdb_stdlog,
7109 "infrun: switching back to stepped thread\n");
7111 if (keep_going_stepped_thread (stepping_thread))
7113 prepare_to_wait (ecs);
7122 /* Set a previously stepped thread back to stepping. Returns true on
7123 success, false if the resume is not possible (e.g., the thread
7127 keep_going_stepped_thread (struct thread_info *tp)
7129 struct frame_info *frame;
7130 struct gdbarch *gdbarch;
7131 struct execution_control_state ecss;
7132 struct execution_control_state *ecs = &ecss;
7134 /* If the stepping thread exited, then don't try to switch back and
7135 resume it, which could fail in several different ways depending
7136 on the target. Instead, just keep going.
7138 We can find a stepping dead thread in the thread list in two
7141 - The target supports thread exit events, and when the target
7142 tries to delete the thread from the thread list, inferior_ptid
7143 pointed at the exiting thread. In such case, calling
7144 delete_thread does not really remove the thread from the list;
7145 instead, the thread is left listed, with 'exited' state.
7147 - The target's debug interface does not support thread exit
7148 events, and so we have no idea whatsoever if the previously
7149 stepping thread is still alive. For that reason, we need to
7150 synchronously query the target now. */
7152 if (is_exited (tp->ptid)
7153 || !target_thread_alive (tp->ptid))
7156 fprintf_unfiltered (gdb_stdlog,
7157 "infrun: not resuming previously "
7158 "stepped thread, it has vanished\n");
7160 delete_thread (tp->ptid);
7165 fprintf_unfiltered (gdb_stdlog,
7166 "infrun: resuming previously stepped thread\n");
7168 reset_ecs (ecs, tp);
7169 switch_to_thread (tp->ptid);
7171 stop_pc = regcache_read_pc (get_thread_regcache (tp->ptid));
7172 frame = get_current_frame ();
7173 gdbarch = get_frame_arch (frame);
7175 /* If the PC of the thread we were trying to single-step has
7176 changed, then that thread has trapped or been signaled, but the
7177 event has not been reported to GDB yet. Re-poll the target
7178 looking for this particular thread's event (i.e. temporarily
7179 enable schedlock) by:
7181 - setting a break at the current PC
7182 - resuming that particular thread, only (by setting trap
7185 This prevents us continuously moving the single-step breakpoint
7186 forward, one instruction at a time, overstepping. */
7188 if (stop_pc != tp->prev_pc)
7193 fprintf_unfiltered (gdb_stdlog,
7194 "infrun: expected thread advanced also (%s -> %s)\n",
7195 paddress (target_gdbarch (), tp->prev_pc),
7196 paddress (target_gdbarch (), stop_pc));
7198 /* Clear the info of the previous step-over, as it's no longer
7199 valid (if the thread was trying to step over a breakpoint, it
7200 has already succeeded). It's what keep_going would do too,
7201 if we called it. Do this before trying to insert the sss
7202 breakpoint, otherwise if we were previously trying to step
7203 over this exact address in another thread, the breakpoint is
7205 clear_step_over_info ();
7206 tp->control.trap_expected = 0;
7208 insert_single_step_breakpoint (get_frame_arch (frame),
7209 get_frame_address_space (frame),
7213 resume_ptid = internal_resume_ptid (tp->control.stepping_command);
7214 do_target_resume (resume_ptid, 0, GDB_SIGNAL_0);
7219 fprintf_unfiltered (gdb_stdlog,
7220 "infrun: expected thread still hasn't advanced\n");
7222 keep_going_pass_signal (ecs);
7227 /* Is thread TP in the middle of (software or hardware)
7228 single-stepping? (Note the result of this function must never be
7229 passed directly as target_resume's STEP parameter.) */
7232 currently_stepping (struct thread_info *tp)
7234 return ((tp->control.step_range_end
7235 && tp->control.step_resume_breakpoint == NULL)
7236 || tp->control.trap_expected
7237 || tp->stepped_breakpoint
7238 || bpstat_should_step ());
7241 /* Inferior has stepped into a subroutine call with source code that
7242 we should not step over. Do step to the first line of code in
7246 handle_step_into_function (struct gdbarch *gdbarch,
7247 struct execution_control_state *ecs)
7249 struct compunit_symtab *cust;
7250 struct symtab_and_line stop_func_sal, sr_sal;
7252 fill_in_stop_func (gdbarch, ecs);
7254 cust = find_pc_compunit_symtab (stop_pc);
7255 if (cust != NULL && compunit_language (cust) != language_asm)
7256 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
7257 ecs->stop_func_start);
7259 stop_func_sal = find_pc_line (ecs->stop_func_start, 0);
7260 /* Use the step_resume_break to step until the end of the prologue,
7261 even if that involves jumps (as it seems to on the vax under
7263 /* If the prologue ends in the middle of a source line, continue to
7264 the end of that source line (if it is still within the function).
7265 Otherwise, just go to end of prologue. */
7266 if (stop_func_sal.end
7267 && stop_func_sal.pc != ecs->stop_func_start
7268 && stop_func_sal.end < ecs->stop_func_end)
7269 ecs->stop_func_start = stop_func_sal.end;
7271 /* Architectures which require breakpoint adjustment might not be able
7272 to place a breakpoint at the computed address. If so, the test
7273 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7274 ecs->stop_func_start to an address at which a breakpoint may be
7275 legitimately placed.
7277 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7278 made, GDB will enter an infinite loop when stepping through
7279 optimized code consisting of VLIW instructions which contain
7280 subinstructions corresponding to different source lines. On
7281 FR-V, it's not permitted to place a breakpoint on any but the
7282 first subinstruction of a VLIW instruction. When a breakpoint is
7283 set, GDB will adjust the breakpoint address to the beginning of
7284 the VLIW instruction. Thus, we need to make the corresponding
7285 adjustment here when computing the stop address. */
7287 if (gdbarch_adjust_breakpoint_address_p (gdbarch))
7289 ecs->stop_func_start
7290 = gdbarch_adjust_breakpoint_address (gdbarch,
7291 ecs->stop_func_start);
7294 if (ecs->stop_func_start == stop_pc)
7296 /* We are already there: stop now. */
7297 end_stepping_range (ecs);
7302 /* Put the step-breakpoint there and go until there. */
7303 init_sal (&sr_sal); /* initialize to zeroes */
7304 sr_sal.pc = ecs->stop_func_start;
7305 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
7306 sr_sal.pspace = get_frame_program_space (get_current_frame ());
7308 /* Do not specify what the fp should be when we stop since on
7309 some machines the prologue is where the new fp value is
7311 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal, null_frame_id);
7313 /* And make sure stepping stops right away then. */
7314 ecs->event_thread->control.step_range_end
7315 = ecs->event_thread->control.step_range_start;
7320 /* Inferior has stepped backward into a subroutine call with source
7321 code that we should not step over. Do step to the beginning of the
7322 last line of code in it. */
7325 handle_step_into_function_backward (struct gdbarch *gdbarch,
7326 struct execution_control_state *ecs)
7328 struct compunit_symtab *cust;
7329 struct symtab_and_line stop_func_sal;
7331 fill_in_stop_func (gdbarch, ecs);
7333 cust = find_pc_compunit_symtab (stop_pc);
7334 if (cust != NULL && compunit_language (cust) != language_asm)
7335 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
7336 ecs->stop_func_start);
7338 stop_func_sal = find_pc_line (stop_pc, 0);
7340 /* OK, we're just going to keep stepping here. */
7341 if (stop_func_sal.pc == stop_pc)
7343 /* We're there already. Just stop stepping now. */
7344 end_stepping_range (ecs);
7348 /* Else just reset the step range and keep going.
7349 No step-resume breakpoint, they don't work for
7350 epilogues, which can have multiple entry paths. */
7351 ecs->event_thread->control.step_range_start = stop_func_sal.pc;
7352 ecs->event_thread->control.step_range_end = stop_func_sal.end;
7358 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7359 This is used to both functions and to skip over code. */
7362 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch *gdbarch,
7363 struct symtab_and_line sr_sal,
7364 struct frame_id sr_id,
7365 enum bptype sr_type)
7367 /* There should never be more than one step-resume or longjmp-resume
7368 breakpoint per thread, so we should never be setting a new
7369 step_resume_breakpoint when one is already active. */
7370 gdb_assert (inferior_thread ()->control.step_resume_breakpoint == NULL);
7371 gdb_assert (sr_type == bp_step_resume || sr_type == bp_hp_step_resume);
7374 fprintf_unfiltered (gdb_stdlog,
7375 "infrun: inserting step-resume breakpoint at %s\n",
7376 paddress (gdbarch, sr_sal.pc));
7378 inferior_thread ()->control.step_resume_breakpoint
7379 = set_momentary_breakpoint (gdbarch, sr_sal, sr_id, sr_type);
7383 insert_step_resume_breakpoint_at_sal (struct gdbarch *gdbarch,
7384 struct symtab_and_line sr_sal,
7385 struct frame_id sr_id)
7387 insert_step_resume_breakpoint_at_sal_1 (gdbarch,
7392 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7393 This is used to skip a potential signal handler.
7395 This is called with the interrupted function's frame. The signal
7396 handler, when it returns, will resume the interrupted function at
7400 insert_hp_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
7402 struct symtab_and_line sr_sal;
7403 struct gdbarch *gdbarch;
7405 gdb_assert (return_frame != NULL);
7406 init_sal (&sr_sal); /* initialize to zeros */
7408 gdbarch = get_frame_arch (return_frame);
7409 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch, get_frame_pc (return_frame));
7410 sr_sal.section = find_pc_overlay (sr_sal.pc);
7411 sr_sal.pspace = get_frame_program_space (return_frame);
7413 insert_step_resume_breakpoint_at_sal_1 (gdbarch, sr_sal,
7414 get_stack_frame_id (return_frame),
7418 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7419 is used to skip a function after stepping into it (for "next" or if
7420 the called function has no debugging information).
7422 The current function has almost always been reached by single
7423 stepping a call or return instruction. NEXT_FRAME belongs to the
7424 current function, and the breakpoint will be set at the caller's
7427 This is a separate function rather than reusing
7428 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7429 get_prev_frame, which may stop prematurely (see the implementation
7430 of frame_unwind_caller_id for an example). */
7433 insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame)
7435 struct symtab_and_line sr_sal;
7436 struct gdbarch *gdbarch;
7438 /* We shouldn't have gotten here if we don't know where the call site
7440 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame)));
7442 init_sal (&sr_sal); /* initialize to zeros */
7444 gdbarch = frame_unwind_caller_arch (next_frame);
7445 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch,
7446 frame_unwind_caller_pc (next_frame));
7447 sr_sal.section = find_pc_overlay (sr_sal.pc);
7448 sr_sal.pspace = frame_unwind_program_space (next_frame);
7450 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal,
7451 frame_unwind_caller_id (next_frame));
7454 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7455 new breakpoint at the target of a jmp_buf. The handling of
7456 longjmp-resume uses the same mechanisms used for handling
7457 "step-resume" breakpoints. */
7460 insert_longjmp_resume_breakpoint (struct gdbarch *gdbarch, CORE_ADDR pc)
7462 /* There should never be more than one longjmp-resume breakpoint per
7463 thread, so we should never be setting a new
7464 longjmp_resume_breakpoint when one is already active. */
7465 gdb_assert (inferior_thread ()->control.exception_resume_breakpoint == NULL);
7468 fprintf_unfiltered (gdb_stdlog,
7469 "infrun: inserting longjmp-resume breakpoint at %s\n",
7470 paddress (gdbarch, pc));
7472 inferior_thread ()->control.exception_resume_breakpoint =
7473 set_momentary_breakpoint_at_pc (gdbarch, pc, bp_longjmp_resume);
7476 /* Insert an exception resume breakpoint. TP is the thread throwing
7477 the exception. The block B is the block of the unwinder debug hook
7478 function. FRAME is the frame corresponding to the call to this
7479 function. SYM is the symbol of the function argument holding the
7480 target PC of the exception. */
7483 insert_exception_resume_breakpoint (struct thread_info *tp,
7484 const struct block *b,
7485 struct frame_info *frame,
7490 struct block_symbol vsym;
7491 struct value *value;
7493 struct breakpoint *bp;
7495 vsym = lookup_symbol (SYMBOL_LINKAGE_NAME (sym), b, VAR_DOMAIN, NULL);
7496 value = read_var_value (vsym.symbol, vsym.block, frame);
7497 /* If the value was optimized out, revert to the old behavior. */
7498 if (! value_optimized_out (value))
7500 handler = value_as_address (value);
7503 fprintf_unfiltered (gdb_stdlog,
7504 "infrun: exception resume at %lx\n",
7505 (unsigned long) handler);
7507 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
7508 handler, bp_exception_resume);
7510 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7513 bp->thread = tp->num;
7514 inferior_thread ()->control.exception_resume_breakpoint = bp;
7517 CATCH (e, RETURN_MASK_ERROR)
7519 /* We want to ignore errors here. */
7524 /* A helper for check_exception_resume that sets an
7525 exception-breakpoint based on a SystemTap probe. */
7528 insert_exception_resume_from_probe (struct thread_info *tp,
7529 const struct bound_probe *probe,
7530 struct frame_info *frame)
7532 struct value *arg_value;
7534 struct breakpoint *bp;
7536 arg_value = probe_safe_evaluate_at_pc (frame, 1);
7540 handler = value_as_address (arg_value);
7543 fprintf_unfiltered (gdb_stdlog,
7544 "infrun: exception resume at %s\n",
7545 paddress (get_objfile_arch (probe->objfile),
7548 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
7549 handler, bp_exception_resume);
7550 bp->thread = tp->num;
7551 inferior_thread ()->control.exception_resume_breakpoint = bp;
7554 /* This is called when an exception has been intercepted. Check to
7555 see whether the exception's destination is of interest, and if so,
7556 set an exception resume breakpoint there. */
7559 check_exception_resume (struct execution_control_state *ecs,
7560 struct frame_info *frame)
7562 struct bound_probe probe;
7563 struct symbol *func;
7565 /* First see if this exception unwinding breakpoint was set via a
7566 SystemTap probe point. If so, the probe has two arguments: the
7567 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7568 set a breakpoint there. */
7569 probe = find_probe_by_pc (get_frame_pc (frame));
7572 insert_exception_resume_from_probe (ecs->event_thread, &probe, frame);
7576 func = get_frame_function (frame);
7582 const struct block *b;
7583 struct block_iterator iter;
7587 /* The exception breakpoint is a thread-specific breakpoint on
7588 the unwinder's debug hook, declared as:
7590 void _Unwind_DebugHook (void *cfa, void *handler);
7592 The CFA argument indicates the frame to which control is
7593 about to be transferred. HANDLER is the destination PC.
7595 We ignore the CFA and set a temporary breakpoint at HANDLER.
7596 This is not extremely efficient but it avoids issues in gdb
7597 with computing the DWARF CFA, and it also works even in weird
7598 cases such as throwing an exception from inside a signal
7601 b = SYMBOL_BLOCK_VALUE (func);
7602 ALL_BLOCK_SYMBOLS (b, iter, sym)
7604 if (!SYMBOL_IS_ARGUMENT (sym))
7611 insert_exception_resume_breakpoint (ecs->event_thread,
7617 CATCH (e, RETURN_MASK_ERROR)
7624 stop_waiting (struct execution_control_state *ecs)
7627 fprintf_unfiltered (gdb_stdlog, "infrun: stop_waiting\n");
7629 clear_step_over_info ();
7631 /* Let callers know we don't want to wait for the inferior anymore. */
7632 ecs->wait_some_more = 0;
7634 /* If all-stop, but the target is always in non-stop mode, stop all
7635 threads now that we're presenting the stop to the user. */
7636 if (!non_stop && target_is_non_stop_p ())
7637 stop_all_threads ();
7640 /* Like keep_going, but passes the signal to the inferior, even if the
7641 signal is set to nopass. */
7644 keep_going_pass_signal (struct execution_control_state *ecs)
7646 /* Make sure normal_stop is called if we get a QUIT handled before
7648 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
7650 gdb_assert (ptid_equal (ecs->event_thread->ptid, inferior_ptid));
7651 gdb_assert (!ecs->event_thread->resumed);
7653 /* Save the pc before execution, to compare with pc after stop. */
7654 ecs->event_thread->prev_pc
7655 = regcache_read_pc (get_thread_regcache (ecs->ptid));
7657 if (ecs->event_thread->control.trap_expected)
7659 struct thread_info *tp = ecs->event_thread;
7662 fprintf_unfiltered (gdb_stdlog,
7663 "infrun: %s has trap_expected set, "
7664 "resuming to collect trap\n",
7665 target_pid_to_str (tp->ptid));
7667 /* We haven't yet gotten our trap, and either: intercepted a
7668 non-signal event (e.g., a fork); or took a signal which we
7669 are supposed to pass through to the inferior. Simply
7671 discard_cleanups (old_cleanups);
7672 resume (ecs->event_thread->suspend.stop_signal);
7674 else if (step_over_info_valid_p ())
7676 /* Another thread is stepping over a breakpoint in-line. If
7677 this thread needs a step-over too, queue the request. In
7678 either case, this resume must be deferred for later. */
7679 struct thread_info *tp = ecs->event_thread;
7681 if (ecs->hit_singlestep_breakpoint
7682 || thread_still_needs_step_over (tp))
7685 fprintf_unfiltered (gdb_stdlog,
7686 "infrun: step-over already in progress: "
7687 "step-over for %s deferred\n",
7688 target_pid_to_str (tp->ptid));
7689 thread_step_over_chain_enqueue (tp);
7694 fprintf_unfiltered (gdb_stdlog,
7695 "infrun: step-over in progress: "
7696 "resume of %s deferred\n",
7697 target_pid_to_str (tp->ptid));
7700 discard_cleanups (old_cleanups);
7704 struct regcache *regcache = get_current_regcache ();
7707 step_over_what step_what;
7709 /* Either the trap was not expected, but we are continuing
7710 anyway (if we got a signal, the user asked it be passed to
7713 We got our expected trap, but decided we should resume from
7716 We're going to run this baby now!
7718 Note that insert_breakpoints won't try to re-insert
7719 already inserted breakpoints. Therefore, we don't
7720 care if breakpoints were already inserted, or not. */
7722 /* If we need to step over a breakpoint, and we're not using
7723 displaced stepping to do so, insert all breakpoints
7724 (watchpoints, etc.) but the one we're stepping over, step one
7725 instruction, and then re-insert the breakpoint when that step
7728 step_what = thread_still_needs_step_over (ecs->event_thread);
7730 remove_bp = (ecs->hit_singlestep_breakpoint
7731 || (step_what & STEP_OVER_BREAKPOINT));
7732 remove_wps = (step_what & STEP_OVER_WATCHPOINT);
7734 /* We can't use displaced stepping if we need to step past a
7735 watchpoint. The instruction copied to the scratch pad would
7736 still trigger the watchpoint. */
7738 && (remove_wps || !use_displaced_stepping (ecs->event_thread)))
7740 set_step_over_info (get_regcache_aspace (regcache),
7741 regcache_read_pc (regcache), remove_wps);
7743 else if (remove_wps)
7744 set_step_over_info (NULL, 0, remove_wps);
7746 /* If we now need to do an in-line step-over, we need to stop
7747 all other threads. Note this must be done before
7748 insert_breakpoints below, because that removes the breakpoint
7749 we're about to step over, otherwise other threads could miss
7751 if (step_over_info_valid_p () && target_is_non_stop_p ())
7752 stop_all_threads ();
7754 /* Stop stepping if inserting breakpoints fails. */
7757 insert_breakpoints ();
7759 CATCH (e, RETURN_MASK_ERROR)
7761 exception_print (gdb_stderr, e);
7763 discard_cleanups (old_cleanups);
7768 ecs->event_thread->control.trap_expected = (remove_bp || remove_wps);
7770 discard_cleanups (old_cleanups);
7771 resume (ecs->event_thread->suspend.stop_signal);
7774 prepare_to_wait (ecs);
7777 /* Called when we should continue running the inferior, because the
7778 current event doesn't cause a user visible stop. This does the
7779 resuming part; waiting for the next event is done elsewhere. */
7782 keep_going (struct execution_control_state *ecs)
7784 if (ecs->event_thread->control.trap_expected
7785 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
7786 ecs->event_thread->control.trap_expected = 0;
7788 if (!signal_program[ecs->event_thread->suspend.stop_signal])
7789 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
7790 keep_going_pass_signal (ecs);
7793 /* This function normally comes after a resume, before
7794 handle_inferior_event exits. It takes care of any last bits of
7795 housekeeping, and sets the all-important wait_some_more flag. */
7798 prepare_to_wait (struct execution_control_state *ecs)
7801 fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n");
7803 ecs->wait_some_more = 1;
7805 if (!target_is_async_p ())
7806 mark_infrun_async_event_handler ();
7809 /* We are done with the step range of a step/next/si/ni command.
7810 Called once for each n of a "step n" operation. */
7813 end_stepping_range (struct execution_control_state *ecs)
7815 ecs->event_thread->control.stop_step = 1;
7819 /* Several print_*_reason functions to print why the inferior has stopped.
7820 We always print something when the inferior exits, or receives a signal.
7821 The rest of the cases are dealt with later on in normal_stop and
7822 print_it_typical. Ideally there should be a call to one of these
7823 print_*_reason functions functions from handle_inferior_event each time
7824 stop_waiting is called.
7826 Note that we don't call these directly, instead we delegate that to
7827 the interpreters, through observers. Interpreters then call these
7828 with whatever uiout is right. */
7831 print_end_stepping_range_reason (struct ui_out *uiout)
7833 /* For CLI-like interpreters, print nothing. */
7835 if (ui_out_is_mi_like_p (uiout))
7837 ui_out_field_string (uiout, "reason",
7838 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE));
7843 print_signal_exited_reason (struct ui_out *uiout, enum gdb_signal siggnal)
7845 annotate_signalled ();
7846 if (ui_out_is_mi_like_p (uiout))
7848 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED));
7849 ui_out_text (uiout, "\nProgram terminated with signal ");
7850 annotate_signal_name ();
7851 ui_out_field_string (uiout, "signal-name",
7852 gdb_signal_to_name (siggnal));
7853 annotate_signal_name_end ();
7854 ui_out_text (uiout, ", ");
7855 annotate_signal_string ();
7856 ui_out_field_string (uiout, "signal-meaning",
7857 gdb_signal_to_string (siggnal));
7858 annotate_signal_string_end ();
7859 ui_out_text (uiout, ".\n");
7860 ui_out_text (uiout, "The program no longer exists.\n");
7864 print_exited_reason (struct ui_out *uiout, int exitstatus)
7866 struct inferior *inf = current_inferior ();
7867 const char *pidstr = target_pid_to_str (pid_to_ptid (inf->pid));
7869 annotate_exited (exitstatus);
7872 if (ui_out_is_mi_like_p (uiout))
7873 ui_out_field_string (uiout, "reason",
7874 async_reason_lookup (EXEC_ASYNC_EXITED));
7875 ui_out_text (uiout, "[Inferior ");
7876 ui_out_text (uiout, plongest (inf->num));
7877 ui_out_text (uiout, " (");
7878 ui_out_text (uiout, pidstr);
7879 ui_out_text (uiout, ") exited with code ");
7880 ui_out_field_fmt (uiout, "exit-code", "0%o", (unsigned int) exitstatus);
7881 ui_out_text (uiout, "]\n");
7885 if (ui_out_is_mi_like_p (uiout))
7887 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY));
7888 ui_out_text (uiout, "[Inferior ");
7889 ui_out_text (uiout, plongest (inf->num));
7890 ui_out_text (uiout, " (");
7891 ui_out_text (uiout, pidstr);
7892 ui_out_text (uiout, ") exited normally]\n");
7897 print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal)
7901 if (siggnal == GDB_SIGNAL_0 && !ui_out_is_mi_like_p (uiout))
7903 struct thread_info *t = inferior_thread ();
7905 ui_out_text (uiout, "\n[");
7906 ui_out_field_string (uiout, "thread-name",
7907 target_pid_to_str (t->ptid));
7908 ui_out_field_fmt (uiout, "thread-id", "] #%d", t->num);
7909 ui_out_text (uiout, " stopped");
7913 ui_out_text (uiout, "\nProgram received signal ");
7914 annotate_signal_name ();
7915 if (ui_out_is_mi_like_p (uiout))
7917 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
7918 ui_out_field_string (uiout, "signal-name",
7919 gdb_signal_to_name (siggnal));
7920 annotate_signal_name_end ();
7921 ui_out_text (uiout, ", ");
7922 annotate_signal_string ();
7923 ui_out_field_string (uiout, "signal-meaning",
7924 gdb_signal_to_string (siggnal));
7925 annotate_signal_string_end ();
7927 ui_out_text (uiout, ".\n");
7931 print_no_history_reason (struct ui_out *uiout)
7933 ui_out_text (uiout, "\nNo more reverse-execution history.\n");
7936 /* Print current location without a level number, if we have changed
7937 functions or hit a breakpoint. Print source line if we have one.
7938 bpstat_print contains the logic deciding in detail what to print,
7939 based on the event(s) that just occurred. */
7942 print_stop_location (struct target_waitstatus *ws)
7945 enum print_what source_flag;
7946 int do_frame_printing = 1;
7947 struct thread_info *tp = inferior_thread ();
7949 bpstat_ret = bpstat_print (tp->control.stop_bpstat, ws->kind);
7953 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
7954 should) carry around the function and does (or should) use
7955 that when doing a frame comparison. */
7956 if (tp->control.stop_step
7957 && frame_id_eq (tp->control.step_frame_id,
7958 get_frame_id (get_current_frame ()))
7959 && tp->control.step_start_function == find_pc_function (stop_pc))
7961 /* Finished step, just print source line. */
7962 source_flag = SRC_LINE;
7966 /* Print location and source line. */
7967 source_flag = SRC_AND_LOC;
7970 case PRINT_SRC_AND_LOC:
7971 /* Print location and source line. */
7972 source_flag = SRC_AND_LOC;
7974 case PRINT_SRC_ONLY:
7975 source_flag = SRC_LINE;
7978 /* Something bogus. */
7979 source_flag = SRC_LINE;
7980 do_frame_printing = 0;
7983 internal_error (__FILE__, __LINE__, _("Unknown value."));
7986 /* The behavior of this routine with respect to the source
7988 SRC_LINE: Print only source line
7989 LOCATION: Print only location
7990 SRC_AND_LOC: Print location and source line. */
7991 if (do_frame_printing)
7992 print_stack_frame (get_selected_frame (NULL), 0, source_flag, 1);
7995 /* Cleanup that restores a previous current uiout. */
7998 restore_current_uiout_cleanup (void *arg)
8000 struct ui_out *saved_uiout = (struct ui_out *) arg;
8002 current_uiout = saved_uiout;
8008 print_stop_event (struct ui_out *uiout)
8010 struct cleanup *old_chain;
8011 struct target_waitstatus last;
8013 struct thread_info *tp;
8015 get_last_target_status (&last_ptid, &last);
8017 old_chain = make_cleanup (restore_current_uiout_cleanup, current_uiout);
8018 current_uiout = uiout;
8020 print_stop_location (&last);
8022 /* Display the auto-display expressions. */
8025 do_cleanups (old_chain);
8027 tp = inferior_thread ();
8028 if (tp->thread_fsm != NULL
8029 && thread_fsm_finished_p (tp->thread_fsm))
8031 struct return_value_info *rv;
8033 rv = thread_fsm_return_value (tp->thread_fsm);
8035 print_return_value (uiout, rv);
8042 maybe_remove_breakpoints (void)
8044 if (!breakpoints_should_be_inserted_now () && target_has_execution)
8046 if (remove_breakpoints ())
8048 target_terminal_ours_for_output ();
8049 printf_filtered (_("Cannot remove breakpoints because "
8050 "program is no longer writable.\nFurther "
8051 "execution is probably impossible.\n"));
8056 /* The execution context that just caused a normal stop. */
8063 /* The event PTID. */
8067 /* If stopp for a thread event, this is the thread that caused the
8069 struct thread_info *thread;
8071 /* The inferior that caused the stop. */
8075 /* Returns a new stop context. If stopped for a thread event, this
8076 takes a strong reference to the thread. */
8078 static struct stop_context *
8079 save_stop_context (void)
8081 struct stop_context *sc = XNEW (struct stop_context);
8083 sc->stop_id = get_stop_id ();
8084 sc->ptid = inferior_ptid;
8085 sc->inf_num = current_inferior ()->num;
8087 if (!ptid_equal (inferior_ptid, null_ptid))
8089 /* Take a strong reference so that the thread can't be deleted
8091 sc->thread = inferior_thread ();
8092 sc->thread->refcount++;
8100 /* Release a stop context previously created with save_stop_context.
8101 Releases the strong reference to the thread as well. */
8104 release_stop_context_cleanup (void *arg)
8106 struct stop_context *sc = (struct stop_context *) arg;
8108 if (sc->thread != NULL)
8109 sc->thread->refcount--;
8113 /* Return true if the current context no longer matches the saved stop
8117 stop_context_changed (struct stop_context *prev)
8119 if (!ptid_equal (prev->ptid, inferior_ptid))
8121 if (prev->inf_num != current_inferior ()->num)
8123 if (prev->thread != NULL && prev->thread->state != THREAD_STOPPED)
8125 if (get_stop_id () != prev->stop_id)
8135 struct target_waitstatus last;
8137 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
8140 get_last_target_status (&last_ptid, &last);
8144 /* If an exception is thrown from this point on, make sure to
8145 propagate GDB's knowledge of the executing state to the
8146 frontend/user running state. A QUIT is an easy exception to see
8147 here, so do this before any filtered output. */
8149 make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
8150 else if (last.kind == TARGET_WAITKIND_SIGNALLED
8151 || last.kind == TARGET_WAITKIND_EXITED)
8153 /* On some targets, we may still have live threads in the
8154 inferior when we get a process exit event. E.g., for
8155 "checkpoint", when the current checkpoint/fork exits,
8156 linux-fork.c automatically switches to another fork from
8157 within target_mourn_inferior. */
8158 if (!ptid_equal (inferior_ptid, null_ptid))
8160 pid_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
8161 make_cleanup (finish_thread_state_cleanup, &pid_ptid);
8164 else if (last.kind != TARGET_WAITKIND_NO_RESUMED)
8165 make_cleanup (finish_thread_state_cleanup, &inferior_ptid);
8167 /* As we're presenting a stop, and potentially removing breakpoints,
8168 update the thread list so we can tell whether there are threads
8169 running on the target. With target remote, for example, we can
8170 only learn about new threads when we explicitly update the thread
8171 list. Do this before notifying the interpreters about signal
8172 stops, end of stepping ranges, etc., so that the "new thread"
8173 output is emitted before e.g., "Program received signal FOO",
8174 instead of after. */
8175 update_thread_list ();
8177 if (last.kind == TARGET_WAITKIND_STOPPED && stopped_by_random_signal)
8178 observer_notify_signal_received (inferior_thread ()->suspend.stop_signal);
8180 /* As with the notification of thread events, we want to delay
8181 notifying the user that we've switched thread context until
8182 the inferior actually stops.
8184 There's no point in saying anything if the inferior has exited.
8185 Note that SIGNALLED here means "exited with a signal", not
8186 "received a signal".
8188 Also skip saying anything in non-stop mode. In that mode, as we
8189 don't want GDB to switch threads behind the user's back, to avoid
8190 races where the user is typing a command to apply to thread x,
8191 but GDB switches to thread y before the user finishes entering
8192 the command, fetch_inferior_event installs a cleanup to restore
8193 the current thread back to the thread the user had selected right
8194 after this event is handled, so we're not really switching, only
8195 informing of a stop. */
8197 && !ptid_equal (previous_inferior_ptid, inferior_ptid)
8198 && target_has_execution
8199 && last.kind != TARGET_WAITKIND_SIGNALLED
8200 && last.kind != TARGET_WAITKIND_EXITED
8201 && last.kind != TARGET_WAITKIND_NO_RESUMED)
8203 target_terminal_ours_for_output ();
8204 printf_filtered (_("[Switching to %s]\n"),
8205 target_pid_to_str (inferior_ptid));
8206 annotate_thread_changed ();
8207 previous_inferior_ptid = inferior_ptid;
8210 if (last.kind == TARGET_WAITKIND_NO_RESUMED)
8212 gdb_assert (sync_execution || !target_can_async_p ());
8214 target_terminal_ours_for_output ();
8215 printf_filtered (_("No unwaited-for children left.\n"));
8218 /* Note: this depends on the update_thread_list call above. */
8219 maybe_remove_breakpoints ();
8221 /* If an auto-display called a function and that got a signal,
8222 delete that auto-display to avoid an infinite recursion. */
8224 if (stopped_by_random_signal)
8225 disable_current_display ();
8227 target_terminal_ours ();
8228 async_enable_stdin ();
8230 /* Let the user/frontend see the threads as stopped. */
8231 do_cleanups (old_chain);
8233 /* Select innermost stack frame - i.e., current frame is frame 0,
8234 and current location is based on that. Handle the case where the
8235 dummy call is returning after being stopped. E.g. the dummy call
8236 previously hit a breakpoint. (If the dummy call returns
8237 normally, we won't reach here.) Do this before the stop hook is
8238 run, so that it doesn't get to see the temporary dummy frame,
8239 which is not where we'll present the stop. */
8240 if (has_stack_frames ())
8242 if (stop_stack_dummy == STOP_STACK_DUMMY)
8244 /* Pop the empty frame that contains the stack dummy. This
8245 also restores inferior state prior to the call (struct
8246 infcall_suspend_state). */
8247 struct frame_info *frame = get_current_frame ();
8249 gdb_assert (get_frame_type (frame) == DUMMY_FRAME);
8251 /* frame_pop calls reinit_frame_cache as the last thing it
8252 does which means there's now no selected frame. */
8255 select_frame (get_current_frame ());
8257 /* Set the current source location. */
8258 set_current_sal_from_frame (get_current_frame ());
8261 /* Look up the hook_stop and run it (CLI internally handles problem
8262 of stop_command's pre-hook not existing). */
8263 if (stop_command != NULL)
8265 struct stop_context *saved_context = save_stop_context ();
8266 struct cleanup *old_chain
8267 = make_cleanup (release_stop_context_cleanup, saved_context);
8269 catch_errors (hook_stop_stub, stop_command,
8270 "Error while running hook_stop:\n", RETURN_MASK_ALL);
8272 /* If the stop hook resumes the target, then there's no point in
8273 trying to notify about the previous stop; its context is
8274 gone. Likewise if the command switches thread or inferior --
8275 the observers would print a stop for the wrong
8277 if (stop_context_changed (saved_context))
8279 do_cleanups (old_chain);
8282 do_cleanups (old_chain);
8285 /* Notify observers about the stop. This is where the interpreters
8286 print the stop event. */
8287 if (!ptid_equal (inferior_ptid, null_ptid))
8288 observer_notify_normal_stop (inferior_thread ()->control.stop_bpstat,
8291 observer_notify_normal_stop (NULL, stop_print_frame);
8293 annotate_stopped ();
8295 if (target_has_execution)
8297 if (last.kind != TARGET_WAITKIND_SIGNALLED
8298 && last.kind != TARGET_WAITKIND_EXITED)
8299 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8300 Delete any breakpoint that is to be deleted at the next stop. */
8301 breakpoint_auto_delete (inferior_thread ()->control.stop_bpstat);
8304 /* Try to get rid of automatically added inferiors that are no
8305 longer needed. Keeping those around slows down things linearly.
8306 Note that this never removes the current inferior. */
8313 hook_stop_stub (void *cmd)
8315 execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
8320 signal_stop_state (int signo)
8322 return signal_stop[signo];
8326 signal_print_state (int signo)
8328 return signal_print[signo];
8332 signal_pass_state (int signo)
8334 return signal_program[signo];
8338 signal_cache_update (int signo)
8342 for (signo = 0; signo < (int) GDB_SIGNAL_LAST; signo++)
8343 signal_cache_update (signo);
8348 signal_pass[signo] = (signal_stop[signo] == 0
8349 && signal_print[signo] == 0
8350 && signal_program[signo] == 1
8351 && signal_catch[signo] == 0);
8355 signal_stop_update (int signo, int state)
8357 int ret = signal_stop[signo];
8359 signal_stop[signo] = state;
8360 signal_cache_update (signo);
8365 signal_print_update (int signo, int state)
8367 int ret = signal_print[signo];
8369 signal_print[signo] = state;
8370 signal_cache_update (signo);
8375 signal_pass_update (int signo, int state)
8377 int ret = signal_program[signo];
8379 signal_program[signo] = state;
8380 signal_cache_update (signo);
8384 /* Update the global 'signal_catch' from INFO and notify the
8388 signal_catch_update (const unsigned int *info)
8392 for (i = 0; i < GDB_SIGNAL_LAST; ++i)
8393 signal_catch[i] = info[i] > 0;
8394 signal_cache_update (-1);
8395 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
8399 sig_print_header (void)
8401 printf_filtered (_("Signal Stop\tPrint\tPass "
8402 "to program\tDescription\n"));
8406 sig_print_info (enum gdb_signal oursig)
8408 const char *name = gdb_signal_to_name (oursig);
8409 int name_padding = 13 - strlen (name);
8411 if (name_padding <= 0)
8414 printf_filtered ("%s", name);
8415 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
8416 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
8417 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
8418 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
8419 printf_filtered ("%s\n", gdb_signal_to_string (oursig));
8422 /* Specify how various signals in the inferior should be handled. */
8425 handle_command (char *args, int from_tty)
8428 int digits, wordlen;
8429 int sigfirst, signum, siglast;
8430 enum gdb_signal oursig;
8433 unsigned char *sigs;
8434 struct cleanup *old_chain;
8438 error_no_arg (_("signal to handle"));
8441 /* Allocate and zero an array of flags for which signals to handle. */
8443 nsigs = (int) GDB_SIGNAL_LAST;
8444 sigs = (unsigned char *) alloca (nsigs);
8445 memset (sigs, 0, nsigs);
8447 /* Break the command line up into args. */
8449 argv = gdb_buildargv (args);
8450 old_chain = make_cleanup_freeargv (argv);
8452 /* Walk through the args, looking for signal oursigs, signal names, and
8453 actions. Signal numbers and signal names may be interspersed with
8454 actions, with the actions being performed for all signals cumulatively
8455 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8457 while (*argv != NULL)
8459 wordlen = strlen (*argv);
8460 for (digits = 0; isdigit ((*argv)[digits]); digits++)
8464 sigfirst = siglast = -1;
8466 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
8468 /* Apply action to all signals except those used by the
8469 debugger. Silently skip those. */
8472 siglast = nsigs - 1;
8474 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
8476 SET_SIGS (nsigs, sigs, signal_stop);
8477 SET_SIGS (nsigs, sigs, signal_print);
8479 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
8481 UNSET_SIGS (nsigs, sigs, signal_program);
8483 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
8485 SET_SIGS (nsigs, sigs, signal_print);
8487 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
8489 SET_SIGS (nsigs, sigs, signal_program);
8491 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
8493 UNSET_SIGS (nsigs, sigs, signal_stop);
8495 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
8497 SET_SIGS (nsigs, sigs, signal_program);
8499 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
8501 UNSET_SIGS (nsigs, sigs, signal_print);
8502 UNSET_SIGS (nsigs, sigs, signal_stop);
8504 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
8506 UNSET_SIGS (nsigs, sigs, signal_program);
8508 else if (digits > 0)
8510 /* It is numeric. The numeric signal refers to our own
8511 internal signal numbering from target.h, not to host/target
8512 signal number. This is a feature; users really should be
8513 using symbolic names anyway, and the common ones like
8514 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8516 sigfirst = siglast = (int)
8517 gdb_signal_from_command (atoi (*argv));
8518 if ((*argv)[digits] == '-')
8521 gdb_signal_from_command (atoi ((*argv) + digits + 1));
8523 if (sigfirst > siglast)
8525 /* Bet he didn't figure we'd think of this case... */
8533 oursig = gdb_signal_from_name (*argv);
8534 if (oursig != GDB_SIGNAL_UNKNOWN)
8536 sigfirst = siglast = (int) oursig;
8540 /* Not a number and not a recognized flag word => complain. */
8541 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv);
8545 /* If any signal numbers or symbol names were found, set flags for
8546 which signals to apply actions to. */
8548 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
8550 switch ((enum gdb_signal) signum)
8552 case GDB_SIGNAL_TRAP:
8553 case GDB_SIGNAL_INT:
8554 if (!allsigs && !sigs[signum])
8556 if (query (_("%s is used by the debugger.\n\
8557 Are you sure you want to change it? "),
8558 gdb_signal_to_name ((enum gdb_signal) signum)))
8564 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8565 gdb_flush (gdb_stdout);
8570 case GDB_SIGNAL_DEFAULT:
8571 case GDB_SIGNAL_UNKNOWN:
8572 /* Make sure that "all" doesn't print these. */
8583 for (signum = 0; signum < nsigs; signum++)
8586 signal_cache_update (-1);
8587 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
8588 target_program_signals ((int) GDB_SIGNAL_LAST, signal_program);
8592 /* Show the results. */
8593 sig_print_header ();
8594 for (; signum < nsigs; signum++)
8596 sig_print_info ((enum gdb_signal) signum);
8602 do_cleanups (old_chain);
8605 /* Complete the "handle" command. */
8607 static VEC (char_ptr) *
8608 handle_completer (struct cmd_list_element *ignore,
8609 const char *text, const char *word)
8611 VEC (char_ptr) *vec_signals, *vec_keywords, *return_val;
8612 static const char * const keywords[] =
8626 vec_signals = signal_completer (ignore, text, word);
8627 vec_keywords = complete_on_enum (keywords, word, word);
8629 return_val = VEC_merge (char_ptr, vec_signals, vec_keywords);
8630 VEC_free (char_ptr, vec_signals);
8631 VEC_free (char_ptr, vec_keywords);
8636 gdb_signal_from_command (int num)
8638 if (num >= 1 && num <= 15)
8639 return (enum gdb_signal) num;
8640 error (_("Only signals 1-15 are valid as numeric signals.\n\
8641 Use \"info signals\" for a list of symbolic signals."));
8644 /* Print current contents of the tables set by the handle command.
8645 It is possible we should just be printing signals actually used
8646 by the current target (but for things to work right when switching
8647 targets, all signals should be in the signal tables). */
8650 signals_info (char *signum_exp, int from_tty)
8652 enum gdb_signal oursig;
8654 sig_print_header ();
8658 /* First see if this is a symbol name. */
8659 oursig = gdb_signal_from_name (signum_exp);
8660 if (oursig == GDB_SIGNAL_UNKNOWN)
8662 /* No, try numeric. */
8664 gdb_signal_from_command (parse_and_eval_long (signum_exp));
8666 sig_print_info (oursig);
8670 printf_filtered ("\n");
8671 /* These ugly casts brought to you by the native VAX compiler. */
8672 for (oursig = GDB_SIGNAL_FIRST;
8673 (int) oursig < (int) GDB_SIGNAL_LAST;
8674 oursig = (enum gdb_signal) ((int) oursig + 1))
8678 if (oursig != GDB_SIGNAL_UNKNOWN
8679 && oursig != GDB_SIGNAL_DEFAULT && oursig != GDB_SIGNAL_0)
8680 sig_print_info (oursig);
8683 printf_filtered (_("\nUse the \"handle\" command "
8684 "to change these tables.\n"));
8687 /* Check if it makes sense to read $_siginfo from the current thread
8688 at this point. If not, throw an error. */
8691 validate_siginfo_access (void)
8693 /* No current inferior, no siginfo. */
8694 if (ptid_equal (inferior_ptid, null_ptid))
8695 error (_("No thread selected."));
8697 /* Don't try to read from a dead thread. */
8698 if (is_exited (inferior_ptid))
8699 error (_("The current thread has terminated"));
8701 /* ... or from a spinning thread. */
8702 if (is_running (inferior_ptid))
8703 error (_("Selected thread is running."));
8706 /* The $_siginfo convenience variable is a bit special. We don't know
8707 for sure the type of the value until we actually have a chance to
8708 fetch the data. The type can change depending on gdbarch, so it is
8709 also dependent on which thread you have selected.
8711 1. making $_siginfo be an internalvar that creates a new value on
8714 2. making the value of $_siginfo be an lval_computed value. */
8716 /* This function implements the lval_computed support for reading a
8720 siginfo_value_read (struct value *v)
8722 LONGEST transferred;
8724 validate_siginfo_access ();
8727 target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO,
8729 value_contents_all_raw (v),
8731 TYPE_LENGTH (value_type (v)));
8733 if (transferred != TYPE_LENGTH (value_type (v)))
8734 error (_("Unable to read siginfo"));
8737 /* This function implements the lval_computed support for writing a
8741 siginfo_value_write (struct value *v, struct value *fromval)
8743 LONGEST transferred;
8745 validate_siginfo_access ();
8747 transferred = target_write (¤t_target,
8748 TARGET_OBJECT_SIGNAL_INFO,
8750 value_contents_all_raw (fromval),
8752 TYPE_LENGTH (value_type (fromval)));
8754 if (transferred != TYPE_LENGTH (value_type (fromval)))
8755 error (_("Unable to write siginfo"));
8758 static const struct lval_funcs siginfo_value_funcs =
8764 /* Return a new value with the correct type for the siginfo object of
8765 the current thread using architecture GDBARCH. Return a void value
8766 if there's no object available. */
8768 static struct value *
8769 siginfo_make_value (struct gdbarch *gdbarch, struct internalvar *var,
8772 if (target_has_stack
8773 && !ptid_equal (inferior_ptid, null_ptid)
8774 && gdbarch_get_siginfo_type_p (gdbarch))
8776 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8778 return allocate_computed_value (type, &siginfo_value_funcs, NULL);
8781 return allocate_value (builtin_type (gdbarch)->builtin_void);
8785 /* infcall_suspend_state contains state about the program itself like its
8786 registers and any signal it received when it last stopped.
8787 This state must be restored regardless of how the inferior function call
8788 ends (either successfully, or after it hits a breakpoint or signal)
8789 if the program is to properly continue where it left off. */
8791 struct infcall_suspend_state
8793 struct thread_suspend_state thread_suspend;
8797 struct regcache *registers;
8799 /* Format of SIGINFO_DATA or NULL if it is not present. */
8800 struct gdbarch *siginfo_gdbarch;
8802 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8803 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8804 content would be invalid. */
8805 gdb_byte *siginfo_data;
8808 struct infcall_suspend_state *
8809 save_infcall_suspend_state (void)
8811 struct infcall_suspend_state *inf_state;
8812 struct thread_info *tp = inferior_thread ();
8813 struct regcache *regcache = get_current_regcache ();
8814 struct gdbarch *gdbarch = get_regcache_arch (regcache);
8815 gdb_byte *siginfo_data = NULL;
8817 if (gdbarch_get_siginfo_type_p (gdbarch))
8819 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8820 size_t len = TYPE_LENGTH (type);
8821 struct cleanup *back_to;
8823 siginfo_data = (gdb_byte *) xmalloc (len);
8824 back_to = make_cleanup (xfree, siginfo_data);
8826 if (target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
8827 siginfo_data, 0, len) == len)
8828 discard_cleanups (back_to);
8831 /* Errors ignored. */
8832 do_cleanups (back_to);
8833 siginfo_data = NULL;
8837 inf_state = XCNEW (struct infcall_suspend_state);
8841 inf_state->siginfo_gdbarch = gdbarch;
8842 inf_state->siginfo_data = siginfo_data;
8845 inf_state->thread_suspend = tp->suspend;
8847 /* run_inferior_call will not use the signal due to its `proceed' call with
8848 GDB_SIGNAL_0 anyway. */
8849 tp->suspend.stop_signal = GDB_SIGNAL_0;
8851 inf_state->stop_pc = stop_pc;
8853 inf_state->registers = regcache_dup (regcache);
8858 /* Restore inferior session state to INF_STATE. */
8861 restore_infcall_suspend_state (struct infcall_suspend_state *inf_state)
8863 struct thread_info *tp = inferior_thread ();
8864 struct regcache *regcache = get_current_regcache ();
8865 struct gdbarch *gdbarch = get_regcache_arch (regcache);
8867 tp->suspend = inf_state->thread_suspend;
8869 stop_pc = inf_state->stop_pc;
8871 if (inf_state->siginfo_gdbarch == gdbarch)
8873 struct type *type = gdbarch_get_siginfo_type (gdbarch);
8875 /* Errors ignored. */
8876 target_write (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
8877 inf_state->siginfo_data, 0, TYPE_LENGTH (type));
8880 /* The inferior can be gone if the user types "print exit(0)"
8881 (and perhaps other times). */
8882 if (target_has_execution)
8883 /* NB: The register write goes through to the target. */
8884 regcache_cpy (regcache, inf_state->registers);
8886 discard_infcall_suspend_state (inf_state);
8890 do_restore_infcall_suspend_state_cleanup (void *state)
8892 restore_infcall_suspend_state ((struct infcall_suspend_state *) state);
8896 make_cleanup_restore_infcall_suspend_state
8897 (struct infcall_suspend_state *inf_state)
8899 return make_cleanup (do_restore_infcall_suspend_state_cleanup, inf_state);
8903 discard_infcall_suspend_state (struct infcall_suspend_state *inf_state)
8905 regcache_xfree (inf_state->registers);
8906 xfree (inf_state->siginfo_data);
8911 get_infcall_suspend_state_regcache (struct infcall_suspend_state *inf_state)
8913 return inf_state->registers;
8916 /* infcall_control_state contains state regarding gdb's control of the
8917 inferior itself like stepping control. It also contains session state like
8918 the user's currently selected frame. */
8920 struct infcall_control_state
8922 struct thread_control_state thread_control;
8923 struct inferior_control_state inferior_control;
8926 enum stop_stack_kind stop_stack_dummy;
8927 int stopped_by_random_signal;
8929 /* ID if the selected frame when the inferior function call was made. */
8930 struct frame_id selected_frame_id;
8933 /* Save all of the information associated with the inferior<==>gdb
8936 struct infcall_control_state *
8937 save_infcall_control_state (void)
8939 struct infcall_control_state *inf_status =
8940 XNEW (struct infcall_control_state);
8941 struct thread_info *tp = inferior_thread ();
8942 struct inferior *inf = current_inferior ();
8944 inf_status->thread_control = tp->control;
8945 inf_status->inferior_control = inf->control;
8947 tp->control.step_resume_breakpoint = NULL;
8948 tp->control.exception_resume_breakpoint = NULL;
8950 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
8951 chain. If caller's caller is walking the chain, they'll be happier if we
8952 hand them back the original chain when restore_infcall_control_state is
8954 tp->control.stop_bpstat = bpstat_copy (tp->control.stop_bpstat);
8957 inf_status->stop_stack_dummy = stop_stack_dummy;
8958 inf_status->stopped_by_random_signal = stopped_by_random_signal;
8960 inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL));
8966 restore_selected_frame (void *args)
8968 struct frame_id *fid = (struct frame_id *) args;
8969 struct frame_info *frame;
8971 frame = frame_find_by_id (*fid);
8973 /* If inf_status->selected_frame_id is NULL, there was no previously
8977 warning (_("Unable to restore previously selected frame."));
8981 select_frame (frame);
8986 /* Restore inferior session state to INF_STATUS. */
8989 restore_infcall_control_state (struct infcall_control_state *inf_status)
8991 struct thread_info *tp = inferior_thread ();
8992 struct inferior *inf = current_inferior ();
8994 if (tp->control.step_resume_breakpoint)
8995 tp->control.step_resume_breakpoint->disposition = disp_del_at_next_stop;
8997 if (tp->control.exception_resume_breakpoint)
8998 tp->control.exception_resume_breakpoint->disposition
8999 = disp_del_at_next_stop;
9001 /* Handle the bpstat_copy of the chain. */
9002 bpstat_clear (&tp->control.stop_bpstat);
9004 tp->control = inf_status->thread_control;
9005 inf->control = inf_status->inferior_control;
9008 stop_stack_dummy = inf_status->stop_stack_dummy;
9009 stopped_by_random_signal = inf_status->stopped_by_random_signal;
9011 if (target_has_stack)
9013 /* The point of catch_errors is that if the stack is clobbered,
9014 walking the stack might encounter a garbage pointer and
9015 error() trying to dereference it. */
9017 (restore_selected_frame, &inf_status->selected_frame_id,
9018 "Unable to restore previously selected frame:\n",
9019 RETURN_MASK_ERROR) == 0)
9020 /* Error in restoring the selected frame. Select the innermost
9022 select_frame (get_current_frame ());
9029 do_restore_infcall_control_state_cleanup (void *sts)
9031 restore_infcall_control_state ((struct infcall_control_state *) sts);
9035 make_cleanup_restore_infcall_control_state
9036 (struct infcall_control_state *inf_status)
9038 return make_cleanup (do_restore_infcall_control_state_cleanup, inf_status);
9042 discard_infcall_control_state (struct infcall_control_state *inf_status)
9044 if (inf_status->thread_control.step_resume_breakpoint)
9045 inf_status->thread_control.step_resume_breakpoint->disposition
9046 = disp_del_at_next_stop;
9048 if (inf_status->thread_control.exception_resume_breakpoint)
9049 inf_status->thread_control.exception_resume_breakpoint->disposition
9050 = disp_del_at_next_stop;
9052 /* See save_infcall_control_state for info on stop_bpstat. */
9053 bpstat_clear (&inf_status->thread_control.stop_bpstat);
9058 /* restore_inferior_ptid() will be used by the cleanup machinery
9059 to restore the inferior_ptid value saved in a call to
9060 save_inferior_ptid(). */
9063 restore_inferior_ptid (void *arg)
9065 ptid_t *saved_ptid_ptr = (ptid_t *) arg;
9067 inferior_ptid = *saved_ptid_ptr;
9071 /* Save the value of inferior_ptid so that it may be restored by a
9072 later call to do_cleanups(). Returns the struct cleanup pointer
9073 needed for later doing the cleanup. */
9076 save_inferior_ptid (void)
9078 ptid_t *saved_ptid_ptr = XNEW (ptid_t);
9080 *saved_ptid_ptr = inferior_ptid;
9081 return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
9087 clear_exit_convenience_vars (void)
9089 clear_internalvar (lookup_internalvar ("_exitsignal"));
9090 clear_internalvar (lookup_internalvar ("_exitcode"));
9094 /* User interface for reverse debugging:
9095 Set exec-direction / show exec-direction commands
9096 (returns error unless target implements to_set_exec_direction method). */
9098 enum exec_direction_kind execution_direction = EXEC_FORWARD;
9099 static const char exec_forward[] = "forward";
9100 static const char exec_reverse[] = "reverse";
9101 static const char *exec_direction = exec_forward;
9102 static const char *const exec_direction_names[] = {
9109 set_exec_direction_func (char *args, int from_tty,
9110 struct cmd_list_element *cmd)
9112 if (target_can_execute_reverse)
9114 if (!strcmp (exec_direction, exec_forward))
9115 execution_direction = EXEC_FORWARD;
9116 else if (!strcmp (exec_direction, exec_reverse))
9117 execution_direction = EXEC_REVERSE;
9121 exec_direction = exec_forward;
9122 error (_("Target does not support this operation."));
9127 show_exec_direction_func (struct ui_file *out, int from_tty,
9128 struct cmd_list_element *cmd, const char *value)
9130 switch (execution_direction) {
9132 fprintf_filtered (out, _("Forward.\n"));
9135 fprintf_filtered (out, _("Reverse.\n"));
9138 internal_error (__FILE__, __LINE__,
9139 _("bogus execution_direction value: %d"),
9140 (int) execution_direction);
9145 show_schedule_multiple (struct ui_file *file, int from_tty,
9146 struct cmd_list_element *c, const char *value)
9148 fprintf_filtered (file, _("Resuming the execution of threads "
9149 "of all processes is %s.\n"), value);
9152 /* Implementation of `siginfo' variable. */
9154 static const struct internalvar_funcs siginfo_funcs =
9161 /* Callback for infrun's target events source. This is marked when a
9162 thread has a pending status to process. */
9165 infrun_async_inferior_event_handler (gdb_client_data data)
9167 inferior_event_handler (INF_REG_EVENT, NULL);
9171 _initialize_infrun (void)
9175 struct cmd_list_element *c;
9177 /* Register extra event sources in the event loop. */
9178 infrun_async_inferior_event_token
9179 = create_async_event_handler (infrun_async_inferior_event_handler, NULL);
9181 add_info ("signals", signals_info, _("\
9182 What debugger does when program gets various signals.\n\
9183 Specify a signal as argument to print info on that signal only."));
9184 add_info_alias ("handle", "signals", 0);
9186 c = add_com ("handle", class_run, handle_command, _("\
9187 Specify how to handle signals.\n\
9188 Usage: handle SIGNAL [ACTIONS]\n\
9189 Args are signals and actions to apply to those signals.\n\
9190 If no actions are specified, the current settings for the specified signals\n\
9191 will be displayed instead.\n\
9193 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9194 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9195 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9196 The special arg \"all\" is recognized to mean all signals except those\n\
9197 used by the debugger, typically SIGTRAP and SIGINT.\n\
9199 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9200 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9201 Stop means reenter debugger if this signal happens (implies print).\n\
9202 Print means print a message if this signal happens.\n\
9203 Pass means let program see this signal; otherwise program doesn't know.\n\
9204 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9205 Pass and Stop may be combined.\n\
9207 Multiple signals may be specified. Signal numbers and signal names\n\
9208 may be interspersed with actions, with the actions being performed for\n\
9209 all signals cumulatively specified."));
9210 set_cmd_completer (c, handle_completer);
9213 stop_command = add_cmd ("stop", class_obscure,
9214 not_just_help_class_command, _("\
9215 There is no `stop' command, but you can set a hook on `stop'.\n\
9216 This allows you to set a list of commands to be run each time execution\n\
9217 of the program stops."), &cmdlist);
9219 add_setshow_zuinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\
9220 Set inferior debugging."), _("\
9221 Show inferior debugging."), _("\
9222 When non-zero, inferior specific debugging is enabled."),
9225 &setdebuglist, &showdebuglist);
9227 add_setshow_boolean_cmd ("displaced", class_maintenance,
9228 &debug_displaced, _("\
9229 Set displaced stepping debugging."), _("\
9230 Show displaced stepping debugging."), _("\
9231 When non-zero, displaced stepping specific debugging is enabled."),
9233 show_debug_displaced,
9234 &setdebuglist, &showdebuglist);
9236 add_setshow_boolean_cmd ("non-stop", no_class,
9238 Set whether gdb controls the inferior in non-stop mode."), _("\
9239 Show whether gdb controls the inferior in non-stop mode."), _("\
9240 When debugging a multi-threaded program and this setting is\n\
9241 off (the default, also called all-stop mode), when one thread stops\n\
9242 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9243 all other threads in the program while you interact with the thread of\n\
9244 interest. When you continue or step a thread, you can allow the other\n\
9245 threads to run, or have them remain stopped, but while you inspect any\n\
9246 thread's state, all threads stop.\n\
9248 In non-stop mode, when one thread stops, other threads can continue\n\
9249 to run freely. You'll be able to step each thread independently,\n\
9250 leave it stopped or free to run as needed."),
9256 numsigs = (int) GDB_SIGNAL_LAST;
9257 signal_stop = XNEWVEC (unsigned char, numsigs);
9258 signal_print = XNEWVEC (unsigned char, numsigs);
9259 signal_program = XNEWVEC (unsigned char, numsigs);
9260 signal_catch = XNEWVEC (unsigned char, numsigs);
9261 signal_pass = XNEWVEC (unsigned char, numsigs);
9262 for (i = 0; i < numsigs; i++)
9265 signal_print[i] = 1;
9266 signal_program[i] = 1;
9267 signal_catch[i] = 0;
9270 /* Signals caused by debugger's own actions should not be given to
9271 the program afterwards.
9273 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9274 explicitly specifies that it should be delivered to the target
9275 program. Typically, that would occur when a user is debugging a
9276 target monitor on a simulator: the target monitor sets a
9277 breakpoint; the simulator encounters this breakpoint and halts
9278 the simulation handing control to GDB; GDB, noting that the stop
9279 address doesn't map to any known breakpoint, returns control back
9280 to the simulator; the simulator then delivers the hardware
9281 equivalent of a GDB_SIGNAL_TRAP to the program being
9283 signal_program[GDB_SIGNAL_TRAP] = 0;
9284 signal_program[GDB_SIGNAL_INT] = 0;
9286 /* Signals that are not errors should not normally enter the debugger. */
9287 signal_stop[GDB_SIGNAL_ALRM] = 0;
9288 signal_print[GDB_SIGNAL_ALRM] = 0;
9289 signal_stop[GDB_SIGNAL_VTALRM] = 0;
9290 signal_print[GDB_SIGNAL_VTALRM] = 0;
9291 signal_stop[GDB_SIGNAL_PROF] = 0;
9292 signal_print[GDB_SIGNAL_PROF] = 0;
9293 signal_stop[GDB_SIGNAL_CHLD] = 0;
9294 signal_print[GDB_SIGNAL_CHLD] = 0;
9295 signal_stop[GDB_SIGNAL_IO] = 0;
9296 signal_print[GDB_SIGNAL_IO] = 0;
9297 signal_stop[GDB_SIGNAL_POLL] = 0;
9298 signal_print[GDB_SIGNAL_POLL] = 0;
9299 signal_stop[GDB_SIGNAL_URG] = 0;
9300 signal_print[GDB_SIGNAL_URG] = 0;
9301 signal_stop[GDB_SIGNAL_WINCH] = 0;
9302 signal_print[GDB_SIGNAL_WINCH] = 0;
9303 signal_stop[GDB_SIGNAL_PRIO] = 0;
9304 signal_print[GDB_SIGNAL_PRIO] = 0;
9306 /* These signals are used internally by user-level thread
9307 implementations. (See signal(5) on Solaris.) Like the above
9308 signals, a healthy program receives and handles them as part of
9309 its normal operation. */
9310 signal_stop[GDB_SIGNAL_LWP] = 0;
9311 signal_print[GDB_SIGNAL_LWP] = 0;
9312 signal_stop[GDB_SIGNAL_WAITING] = 0;
9313 signal_print[GDB_SIGNAL_WAITING] = 0;
9314 signal_stop[GDB_SIGNAL_CANCEL] = 0;
9315 signal_print[GDB_SIGNAL_CANCEL] = 0;
9317 /* Update cached state. */
9318 signal_cache_update (-1);
9320 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support,
9321 &stop_on_solib_events, _("\
9322 Set stopping for shared library events."), _("\
9323 Show stopping for shared library events."), _("\
9324 If nonzero, gdb will give control to the user when the dynamic linker\n\
9325 notifies gdb of shared library events. The most common event of interest\n\
9326 to the user would be loading/unloading of a new library."),
9327 set_stop_on_solib_events,
9328 show_stop_on_solib_events,
9329 &setlist, &showlist);
9331 add_setshow_enum_cmd ("follow-fork-mode", class_run,
9332 follow_fork_mode_kind_names,
9333 &follow_fork_mode_string, _("\
9334 Set debugger response to a program call of fork or vfork."), _("\
9335 Show debugger response to a program call of fork or vfork."), _("\
9336 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9337 parent - the original process is debugged after a fork\n\
9338 child - the new process is debugged after a fork\n\
9339 The unfollowed process will continue to run.\n\
9340 By default, the debugger will follow the parent process."),
9342 show_follow_fork_mode_string,
9343 &setlist, &showlist);
9345 add_setshow_enum_cmd ("follow-exec-mode", class_run,
9346 follow_exec_mode_names,
9347 &follow_exec_mode_string, _("\
9348 Set debugger response to a program call of exec."), _("\
9349 Show debugger response to a program call of exec."), _("\
9350 An exec call replaces the program image of a process.\n\
9352 follow-exec-mode can be:\n\
9354 new - the debugger creates a new inferior and rebinds the process\n\
9355 to this new inferior. The program the process was running before\n\
9356 the exec call can be restarted afterwards by restarting the original\n\
9359 same - the debugger keeps the process bound to the same inferior.\n\
9360 The new executable image replaces the previous executable loaded in\n\
9361 the inferior. Restarting the inferior after the exec call restarts\n\
9362 the executable the process was running after the exec call.\n\
9364 By default, the debugger will use the same inferior."),
9366 show_follow_exec_mode_string,
9367 &setlist, &showlist);
9369 add_setshow_enum_cmd ("scheduler-locking", class_run,
9370 scheduler_enums, &scheduler_mode, _("\
9371 Set mode for locking scheduler during execution."), _("\
9372 Show mode for locking scheduler during execution."), _("\
9373 off == no locking (threads may preempt at any time)\n\
9374 on == full locking (no thread except the current thread may run)\n\
9375 This applies to both normal execution and replay mode.\n\
9376 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9377 In this mode, other threads may run during other commands.\n\
9378 This applies to both normal execution and replay mode.\n\
9379 replay == scheduler locked in replay mode and unlocked during normal execution."),
9380 set_schedlock_func, /* traps on target vector */
9381 show_scheduler_mode,
9382 &setlist, &showlist);
9384 add_setshow_boolean_cmd ("schedule-multiple", class_run, &sched_multi, _("\
9385 Set mode for resuming threads of all processes."), _("\
9386 Show mode for resuming threads of all processes."), _("\
9387 When on, execution commands (such as 'continue' or 'next') resume all\n\
9388 threads of all processes. When off (which is the default), execution\n\
9389 commands only resume the threads of the current process. The set of\n\
9390 threads that are resumed is further refined by the scheduler-locking\n\
9391 mode (see help set scheduler-locking)."),
9393 show_schedule_multiple,
9394 &setlist, &showlist);
9396 add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\
9397 Set mode of the step operation."), _("\
9398 Show mode of the step operation."), _("\
9399 When set, doing a step over a function without debug line information\n\
9400 will stop at the first instruction of that function. Otherwise, the\n\
9401 function is skipped and the step command stops at a different source line."),
9403 show_step_stop_if_no_debug,
9404 &setlist, &showlist);
9406 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run,
9407 &can_use_displaced_stepping, _("\
9408 Set debugger's willingness to use displaced stepping."), _("\
9409 Show debugger's willingness to use displaced stepping."), _("\
9410 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9411 supported by the target architecture. If off, gdb will not use displaced\n\
9412 stepping to step over breakpoints, even if such is supported by the target\n\
9413 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9414 if the target architecture supports it and non-stop mode is active, but will not\n\
9415 use it in all-stop mode (see help set non-stop)."),
9417 show_can_use_displaced_stepping,
9418 &setlist, &showlist);
9420 add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names,
9421 &exec_direction, _("Set direction of execution.\n\
9422 Options are 'forward' or 'reverse'."),
9423 _("Show direction of execution (forward/reverse)."),
9424 _("Tells gdb whether to execute forward or backward."),
9425 set_exec_direction_func, show_exec_direction_func,
9426 &setlist, &showlist);
9428 /* Set/show detach-on-fork: user-settable mode. */
9430 add_setshow_boolean_cmd ("detach-on-fork", class_run, &detach_fork, _("\
9431 Set whether gdb will detach the child of a fork."), _("\
9432 Show whether gdb will detach the child of a fork."), _("\
9433 Tells gdb whether to detach the child of a fork."),
9434 NULL, NULL, &setlist, &showlist);
9436 /* Set/show disable address space randomization mode. */
9438 add_setshow_boolean_cmd ("disable-randomization", class_support,
9439 &disable_randomization, _("\
9440 Set disabling of debuggee's virtual address space randomization."), _("\
9441 Show disabling of debuggee's virtual address space randomization."), _("\
9442 When this mode is on (which is the default), randomization of the virtual\n\
9443 address space is disabled. Standalone programs run with the randomization\n\
9444 enabled by default on some platforms."),
9445 &set_disable_randomization,
9446 &show_disable_randomization,
9447 &setlist, &showlist);
9449 /* ptid initializations */
9450 inferior_ptid = null_ptid;
9451 target_last_wait_ptid = minus_one_ptid;
9453 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed);
9454 observer_attach_thread_stop_requested (infrun_thread_stop_requested);
9455 observer_attach_thread_exit (infrun_thread_thread_exit);
9456 observer_attach_inferior_exit (infrun_inferior_exit);
9458 /* Explicitly create without lookup, since that tries to create a
9459 value with a void typed value, and when we get here, gdbarch
9460 isn't initialized yet. At this point, we're quite sure there
9461 isn't another convenience variable of the same name. */
9462 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs, NULL);
9464 add_setshow_boolean_cmd ("observer", no_class,
9465 &observer_mode_1, _("\
9466 Set whether gdb controls the inferior in observer mode."), _("\
9467 Show whether gdb controls the inferior in observer mode."), _("\
9468 In observer mode, GDB can get data from the inferior, but not\n\
9469 affect its execution. Registers and memory may not be changed,\n\
9470 breakpoints may not be set, and the program cannot be interrupted\n\