1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2014 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 "exceptions.h"
28 #include "breakpoint.h"
32 #include "cli/cli-script.h"
34 #include "gdbthread.h"
46 #include "dictionary.h"
48 #include "mi/mi-common.h"
49 #include "event-top.h"
51 #include "record-full.h"
52 #include "inline-frame.h"
54 #include "tracepoint.h"
55 #include "continuations.h"
60 #include "completer.h"
61 #include "target-descriptions.h"
62 #include "target-dcache.h"
64 /* Prototypes for local functions */
66 static void signals_info (char *, int);
68 static void handle_command (char *, int);
70 static void sig_print_info (enum gdb_signal);
72 static void sig_print_header (void);
74 static void resume_cleanups (void *);
76 static int hook_stop_stub (void *);
78 static int restore_selected_frame (void *);
80 static int follow_fork (void);
82 static void set_schedlock_func (char *args, int from_tty,
83 struct cmd_list_element *c);
85 static int currently_stepping (struct thread_info *tp);
87 static void xdb_handle_command (char *args, int from_tty);
89 void _initialize_infrun (void);
91 void nullify_last_target_wait_ptid (void);
93 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info *);
95 static void insert_step_resume_breakpoint_at_caller (struct frame_info *);
97 static void insert_longjmp_resume_breakpoint (struct gdbarch *, CORE_ADDR);
99 /* When set, stop the 'step' command if we enter a function which has
100 no line number information. The normal behavior is that we step
101 over such function. */
102 int step_stop_if_no_debug = 0;
104 show_step_stop_if_no_debug (struct ui_file *file, int from_tty,
105 struct cmd_list_element *c, const char *value)
107 fprintf_filtered (file, _("Mode of the step operation is %s.\n"), value);
110 /* In asynchronous mode, but simulating synchronous execution. */
112 int sync_execution = 0;
114 /* proceed and normal_stop use this to notify the user when the
115 inferior stopped in a different thread than it had been running
118 static ptid_t previous_inferior_ptid;
120 /* If set (default for legacy reasons), when following a fork, GDB
121 will detach from one of the fork branches, child or parent.
122 Exactly which branch is detached depends on 'set follow-fork-mode'
125 static int detach_fork = 1;
127 int debug_displaced = 0;
129 show_debug_displaced (struct ui_file *file, int from_tty,
130 struct cmd_list_element *c, const char *value)
132 fprintf_filtered (file, _("Displace stepping debugging is %s.\n"), value);
135 unsigned int debug_infrun = 0;
137 show_debug_infrun (struct ui_file *file, int from_tty,
138 struct cmd_list_element *c, const char *value)
140 fprintf_filtered (file, _("Inferior debugging is %s.\n"), value);
144 /* Support for disabling address space randomization. */
146 int disable_randomization = 1;
149 show_disable_randomization (struct ui_file *file, int from_tty,
150 struct cmd_list_element *c, const char *value)
152 if (target_supports_disable_randomization ())
153 fprintf_filtered (file,
154 _("Disabling randomization of debuggee's "
155 "virtual address space is %s.\n"),
158 fputs_filtered (_("Disabling randomization of debuggee's "
159 "virtual address space is unsupported on\n"
160 "this platform.\n"), file);
164 set_disable_randomization (char *args, int from_tty,
165 struct cmd_list_element *c)
167 if (!target_supports_disable_randomization ())
168 error (_("Disabling randomization of debuggee's "
169 "virtual address space is unsupported on\n"
173 /* User interface for non-stop mode. */
176 static int non_stop_1 = 0;
179 set_non_stop (char *args, int from_tty,
180 struct cmd_list_element *c)
182 if (target_has_execution)
184 non_stop_1 = non_stop;
185 error (_("Cannot change this setting while the inferior is running."));
188 non_stop = non_stop_1;
192 show_non_stop (struct ui_file *file, int from_tty,
193 struct cmd_list_element *c, const char *value)
195 fprintf_filtered (file,
196 _("Controlling the inferior in non-stop mode is %s.\n"),
200 /* "Observer mode" is somewhat like a more extreme version of
201 non-stop, in which all GDB operations that might affect the
202 target's execution have been disabled. */
204 int observer_mode = 0;
205 static int observer_mode_1 = 0;
208 set_observer_mode (char *args, int from_tty,
209 struct cmd_list_element *c)
211 if (target_has_execution)
213 observer_mode_1 = observer_mode;
214 error (_("Cannot change this setting while the inferior is running."));
217 observer_mode = observer_mode_1;
219 may_write_registers = !observer_mode;
220 may_write_memory = !observer_mode;
221 may_insert_breakpoints = !observer_mode;
222 may_insert_tracepoints = !observer_mode;
223 /* We can insert fast tracepoints in or out of observer mode,
224 but enable them if we're going into this mode. */
226 may_insert_fast_tracepoints = 1;
227 may_stop = !observer_mode;
228 update_target_permissions ();
230 /* Going *into* observer mode we must force non-stop, then
231 going out we leave it that way. */
234 pagination_enabled = 0;
235 non_stop = non_stop_1 = 1;
239 printf_filtered (_("Observer mode is now %s.\n"),
240 (observer_mode ? "on" : "off"));
244 show_observer_mode (struct ui_file *file, int from_tty,
245 struct cmd_list_element *c, const char *value)
247 fprintf_filtered (file, _("Observer mode is %s.\n"), value);
250 /* This updates the value of observer mode based on changes in
251 permissions. Note that we are deliberately ignoring the values of
252 may-write-registers and may-write-memory, since the user may have
253 reason to enable these during a session, for instance to turn on a
254 debugging-related global. */
257 update_observer_mode (void)
261 newval = (!may_insert_breakpoints
262 && !may_insert_tracepoints
263 && may_insert_fast_tracepoints
267 /* Let the user know if things change. */
268 if (newval != observer_mode)
269 printf_filtered (_("Observer mode is now %s.\n"),
270 (newval ? "on" : "off"));
272 observer_mode = observer_mode_1 = newval;
275 /* Tables of how to react to signals; the user sets them. */
277 static unsigned char *signal_stop;
278 static unsigned char *signal_print;
279 static unsigned char *signal_program;
281 /* Table of signals that are registered with "catch signal". A
282 non-zero entry indicates that the signal is caught by some "catch
283 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
285 static unsigned char *signal_catch;
287 /* Table of signals that the target may silently handle.
288 This is automatically determined from the flags above,
289 and simply cached here. */
290 static unsigned char *signal_pass;
292 #define SET_SIGS(nsigs,sigs,flags) \
294 int signum = (nsigs); \
295 while (signum-- > 0) \
296 if ((sigs)[signum]) \
297 (flags)[signum] = 1; \
300 #define UNSET_SIGS(nsigs,sigs,flags) \
302 int signum = (nsigs); \
303 while (signum-- > 0) \
304 if ((sigs)[signum]) \
305 (flags)[signum] = 0; \
308 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
309 this function is to avoid exporting `signal_program'. */
312 update_signals_program_target (void)
314 target_program_signals ((int) GDB_SIGNAL_LAST, signal_program);
317 /* Value to pass to target_resume() to cause all threads to resume. */
319 #define RESUME_ALL minus_one_ptid
321 /* Command list pointer for the "stop" placeholder. */
323 static struct cmd_list_element *stop_command;
325 /* Function inferior was in as of last step command. */
327 static struct symbol *step_start_function;
329 /* Nonzero if we want to give control to the user when we're notified
330 of shared library events by the dynamic linker. */
331 int stop_on_solib_events;
333 /* Enable or disable optional shared library event breakpoints
334 as appropriate when the above flag is changed. */
337 set_stop_on_solib_events (char *args, int from_tty, struct cmd_list_element *c)
339 update_solib_breakpoints ();
343 show_stop_on_solib_events (struct ui_file *file, int from_tty,
344 struct cmd_list_element *c, const char *value)
346 fprintf_filtered (file, _("Stopping for shared library events is %s.\n"),
350 /* Nonzero means expecting a trace trap
351 and should stop the inferior and return silently when it happens. */
355 /* Save register contents here when executing a "finish" command or are
356 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
357 Thus this contains the return value from the called function (assuming
358 values are returned in a register). */
360 struct regcache *stop_registers;
362 /* Nonzero after stop if current stack frame should be printed. */
364 static int stop_print_frame;
366 /* This is a cached copy of the pid/waitstatus of the last event
367 returned by target_wait()/deprecated_target_wait_hook(). This
368 information is returned by get_last_target_status(). */
369 static ptid_t target_last_wait_ptid;
370 static struct target_waitstatus target_last_waitstatus;
372 static void context_switch (ptid_t ptid);
374 void init_thread_stepping_state (struct thread_info *tss);
376 static void init_infwait_state (void);
378 static const char follow_fork_mode_child[] = "child";
379 static const char follow_fork_mode_parent[] = "parent";
381 static const char *const follow_fork_mode_kind_names[] = {
382 follow_fork_mode_child,
383 follow_fork_mode_parent,
387 static const char *follow_fork_mode_string = follow_fork_mode_parent;
389 show_follow_fork_mode_string (struct ui_file *file, int from_tty,
390 struct cmd_list_element *c, const char *value)
392 fprintf_filtered (file,
393 _("Debugger response to a program "
394 "call of fork or vfork is \"%s\".\n"),
399 /* Tell the target to follow the fork we're stopped at. Returns true
400 if the inferior should be resumed; false, if the target for some
401 reason decided it's best not to resume. */
406 int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
407 int should_resume = 1;
408 struct thread_info *tp;
410 /* Copy user stepping state to the new inferior thread. FIXME: the
411 followed fork child thread should have a copy of most of the
412 parent thread structure's run control related fields, not just these.
413 Initialized to avoid "may be used uninitialized" warnings from gcc. */
414 struct breakpoint *step_resume_breakpoint = NULL;
415 struct breakpoint *exception_resume_breakpoint = NULL;
416 CORE_ADDR step_range_start = 0;
417 CORE_ADDR step_range_end = 0;
418 struct frame_id step_frame_id = { 0 };
419 struct interp *command_interp = NULL;
424 struct target_waitstatus wait_status;
426 /* Get the last target status returned by target_wait(). */
427 get_last_target_status (&wait_ptid, &wait_status);
429 /* If not stopped at a fork event, then there's nothing else to
431 if (wait_status.kind != TARGET_WAITKIND_FORKED
432 && wait_status.kind != TARGET_WAITKIND_VFORKED)
435 /* Check if we switched over from WAIT_PTID, since the event was
437 if (!ptid_equal (wait_ptid, minus_one_ptid)
438 && !ptid_equal (inferior_ptid, wait_ptid))
440 /* We did. Switch back to WAIT_PTID thread, to tell the
441 target to follow it (in either direction). We'll
442 afterwards refuse to resume, and inform the user what
444 switch_to_thread (wait_ptid);
449 tp = inferior_thread ();
451 /* If there were any forks/vforks that were caught and are now to be
452 followed, then do so now. */
453 switch (tp->pending_follow.kind)
455 case TARGET_WAITKIND_FORKED:
456 case TARGET_WAITKIND_VFORKED:
458 ptid_t parent, child;
460 /* If the user did a next/step, etc, over a fork call,
461 preserve the stepping state in the fork child. */
462 if (follow_child && should_resume)
464 step_resume_breakpoint = clone_momentary_breakpoint
465 (tp->control.step_resume_breakpoint);
466 step_range_start = tp->control.step_range_start;
467 step_range_end = tp->control.step_range_end;
468 step_frame_id = tp->control.step_frame_id;
469 exception_resume_breakpoint
470 = clone_momentary_breakpoint (tp->control.exception_resume_breakpoint);
471 command_interp = tp->control.command_interp;
473 /* For now, delete the parent's sr breakpoint, otherwise,
474 parent/child sr breakpoints are considered duplicates,
475 and the child version will not be installed. Remove
476 this when the breakpoints module becomes aware of
477 inferiors and address spaces. */
478 delete_step_resume_breakpoint (tp);
479 tp->control.step_range_start = 0;
480 tp->control.step_range_end = 0;
481 tp->control.step_frame_id = null_frame_id;
482 delete_exception_resume_breakpoint (tp);
483 tp->control.command_interp = NULL;
486 parent = inferior_ptid;
487 child = tp->pending_follow.value.related_pid;
489 /* Tell the target to do whatever is necessary to follow
490 either parent or child. */
491 if (target_follow_fork (follow_child, detach_fork))
493 /* Target refused to follow, or there's some other reason
494 we shouldn't resume. */
499 /* This pending follow fork event is now handled, one way
500 or another. The previous selected thread may be gone
501 from the lists by now, but if it is still around, need
502 to clear the pending follow request. */
503 tp = find_thread_ptid (parent);
505 tp->pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
507 /* This makes sure we don't try to apply the "Switched
508 over from WAIT_PID" logic above. */
509 nullify_last_target_wait_ptid ();
511 /* If we followed the child, switch to it... */
514 switch_to_thread (child);
516 /* ... and preserve the stepping state, in case the
517 user was stepping over the fork call. */
520 tp = inferior_thread ();
521 tp->control.step_resume_breakpoint
522 = step_resume_breakpoint;
523 tp->control.step_range_start = step_range_start;
524 tp->control.step_range_end = step_range_end;
525 tp->control.step_frame_id = step_frame_id;
526 tp->control.exception_resume_breakpoint
527 = exception_resume_breakpoint;
528 tp->control.command_interp = command_interp;
532 /* If we get here, it was because we're trying to
533 resume from a fork catchpoint, but, the user
534 has switched threads away from the thread that
535 forked. In that case, the resume command
536 issued is most likely not applicable to the
537 child, so just warn, and refuse to resume. */
538 warning (_("Not resuming: switched threads "
539 "before following fork child.\n"));
542 /* Reset breakpoints in the child as appropriate. */
543 follow_inferior_reset_breakpoints ();
546 switch_to_thread (parent);
550 case TARGET_WAITKIND_SPURIOUS:
551 /* Nothing to follow. */
554 internal_error (__FILE__, __LINE__,
555 "Unexpected pending_follow.kind %d\n",
556 tp->pending_follow.kind);
560 return should_resume;
564 follow_inferior_reset_breakpoints (void)
566 struct thread_info *tp = inferior_thread ();
568 /* Was there a step_resume breakpoint? (There was if the user
569 did a "next" at the fork() call.) If so, explicitly reset its
570 thread number. Cloned step_resume breakpoints are disabled on
571 creation, so enable it here now that it is associated with the
574 step_resumes are a form of bp that are made to be per-thread.
575 Since we created the step_resume bp when the parent process
576 was being debugged, and now are switching to the child process,
577 from the breakpoint package's viewpoint, that's a switch of
578 "threads". We must update the bp's notion of which thread
579 it is for, or it'll be ignored when it triggers. */
581 if (tp->control.step_resume_breakpoint)
583 breakpoint_re_set_thread (tp->control.step_resume_breakpoint);
584 tp->control.step_resume_breakpoint->loc->enabled = 1;
587 /* Treat exception_resume breakpoints like step_resume breakpoints. */
588 if (tp->control.exception_resume_breakpoint)
590 breakpoint_re_set_thread (tp->control.exception_resume_breakpoint);
591 tp->control.exception_resume_breakpoint->loc->enabled = 1;
594 /* Reinsert all breakpoints in the child. The user may have set
595 breakpoints after catching the fork, in which case those
596 were never set in the child, but only in the parent. This makes
597 sure the inserted breakpoints match the breakpoint list. */
599 breakpoint_re_set ();
600 insert_breakpoints ();
603 /* The child has exited or execed: resume threads of the parent the
604 user wanted to be executing. */
607 proceed_after_vfork_done (struct thread_info *thread,
610 int pid = * (int *) arg;
612 if (ptid_get_pid (thread->ptid) == pid
613 && is_running (thread->ptid)
614 && !is_executing (thread->ptid)
615 && !thread->stop_requested
616 && thread->suspend.stop_signal == GDB_SIGNAL_0)
619 fprintf_unfiltered (gdb_stdlog,
620 "infrun: resuming vfork parent thread %s\n",
621 target_pid_to_str (thread->ptid));
623 switch_to_thread (thread->ptid);
624 clear_proceed_status (0);
625 proceed ((CORE_ADDR) -1, GDB_SIGNAL_DEFAULT, 0);
631 /* Called whenever we notice an exec or exit event, to handle
632 detaching or resuming a vfork parent. */
635 handle_vfork_child_exec_or_exit (int exec)
637 struct inferior *inf = current_inferior ();
639 if (inf->vfork_parent)
641 int resume_parent = -1;
643 /* This exec or exit marks the end of the shared memory region
644 between the parent and the child. If the user wanted to
645 detach from the parent, now is the time. */
647 if (inf->vfork_parent->pending_detach)
649 struct thread_info *tp;
650 struct cleanup *old_chain;
651 struct program_space *pspace;
652 struct address_space *aspace;
654 /* follow-fork child, detach-on-fork on. */
656 inf->vfork_parent->pending_detach = 0;
660 /* If we're handling a child exit, then inferior_ptid
661 points at the inferior's pid, not to a thread. */
662 old_chain = save_inferior_ptid ();
663 save_current_program_space ();
664 save_current_inferior ();
667 old_chain = save_current_space_and_thread ();
669 /* We're letting loose of the parent. */
670 tp = any_live_thread_of_process (inf->vfork_parent->pid);
671 switch_to_thread (tp->ptid);
673 /* We're about to detach from the parent, which implicitly
674 removes breakpoints from its address space. There's a
675 catch here: we want to reuse the spaces for the child,
676 but, parent/child are still sharing the pspace at this
677 point, although the exec in reality makes the kernel give
678 the child a fresh set of new pages. The problem here is
679 that the breakpoints module being unaware of this, would
680 likely chose the child process to write to the parent
681 address space. Swapping the child temporarily away from
682 the spaces has the desired effect. Yes, this is "sort
685 pspace = inf->pspace;
686 aspace = inf->aspace;
690 if (debug_infrun || info_verbose)
692 target_terminal_ours ();
695 fprintf_filtered (gdb_stdlog,
696 "Detaching vfork parent process "
697 "%d after child exec.\n",
698 inf->vfork_parent->pid);
700 fprintf_filtered (gdb_stdlog,
701 "Detaching vfork parent process "
702 "%d after child exit.\n",
703 inf->vfork_parent->pid);
706 target_detach (NULL, 0);
709 inf->pspace = pspace;
710 inf->aspace = aspace;
712 do_cleanups (old_chain);
716 /* We're staying attached to the parent, so, really give the
717 child a new address space. */
718 inf->pspace = add_program_space (maybe_new_address_space ());
719 inf->aspace = inf->pspace->aspace;
721 set_current_program_space (inf->pspace);
723 resume_parent = inf->vfork_parent->pid;
725 /* Break the bonds. */
726 inf->vfork_parent->vfork_child = NULL;
730 struct cleanup *old_chain;
731 struct program_space *pspace;
733 /* If this is a vfork child exiting, then the pspace and
734 aspaces were shared with the parent. Since we're
735 reporting the process exit, we'll be mourning all that is
736 found in the address space, and switching to null_ptid,
737 preparing to start a new inferior. But, since we don't
738 want to clobber the parent's address/program spaces, we
739 go ahead and create a new one for this exiting
742 /* Switch to null_ptid, so that clone_program_space doesn't want
743 to read the selected frame of a dead process. */
744 old_chain = save_inferior_ptid ();
745 inferior_ptid = null_ptid;
747 /* This inferior is dead, so avoid giving the breakpoints
748 module the option to write through to it (cloning a
749 program space resets breakpoints). */
752 pspace = add_program_space (maybe_new_address_space ());
753 set_current_program_space (pspace);
755 inf->symfile_flags = SYMFILE_NO_READ;
756 clone_program_space (pspace, inf->vfork_parent->pspace);
757 inf->pspace = pspace;
758 inf->aspace = pspace->aspace;
760 /* Put back inferior_ptid. We'll continue mourning this
762 do_cleanups (old_chain);
764 resume_parent = inf->vfork_parent->pid;
765 /* Break the bonds. */
766 inf->vfork_parent->vfork_child = NULL;
769 inf->vfork_parent = NULL;
771 gdb_assert (current_program_space == inf->pspace);
773 if (non_stop && resume_parent != -1)
775 /* If the user wanted the parent to be running, let it go
777 struct cleanup *old_chain = make_cleanup_restore_current_thread ();
780 fprintf_unfiltered (gdb_stdlog,
781 "infrun: resuming vfork parent process %d\n",
784 iterate_over_threads (proceed_after_vfork_done, &resume_parent);
786 do_cleanups (old_chain);
791 /* Enum strings for "set|show follow-exec-mode". */
793 static const char follow_exec_mode_new[] = "new";
794 static const char follow_exec_mode_same[] = "same";
795 static const char *const follow_exec_mode_names[] =
797 follow_exec_mode_new,
798 follow_exec_mode_same,
802 static const char *follow_exec_mode_string = follow_exec_mode_same;
804 show_follow_exec_mode_string (struct ui_file *file, int from_tty,
805 struct cmd_list_element *c, const char *value)
807 fprintf_filtered (file, _("Follow exec mode is \"%s\".\n"), value);
810 /* EXECD_PATHNAME is assumed to be non-NULL. */
813 follow_exec (ptid_t pid, char *execd_pathname)
815 struct thread_info *th = inferior_thread ();
816 struct inferior *inf = current_inferior ();
818 /* This is an exec event that we actually wish to pay attention to.
819 Refresh our symbol table to the newly exec'd program, remove any
822 If there are breakpoints, they aren't really inserted now,
823 since the exec() transformed our inferior into a fresh set
826 We want to preserve symbolic breakpoints on the list, since
827 we have hopes that they can be reset after the new a.out's
828 symbol table is read.
830 However, any "raw" breakpoints must be removed from the list
831 (e.g., the solib bp's), since their address is probably invalid
834 And, we DON'T want to call delete_breakpoints() here, since
835 that may write the bp's "shadow contents" (the instruction
836 value that was overwritten witha TRAP instruction). Since
837 we now have a new a.out, those shadow contents aren't valid. */
839 mark_breakpoints_out ();
841 update_breakpoints_after_exec ();
843 /* If there was one, it's gone now. We cannot truly step-to-next
844 statement through an exec(). */
845 th->control.step_resume_breakpoint = NULL;
846 th->control.exception_resume_breakpoint = NULL;
847 th->control.step_range_start = 0;
848 th->control.step_range_end = 0;
850 /* The target reports the exec event to the main thread, even if
851 some other thread does the exec, and even if the main thread was
852 already stopped --- if debugging in non-stop mode, it's possible
853 the user had the main thread held stopped in the previous image
854 --- release it now. This is the same behavior as step-over-exec
855 with scheduler-locking on in all-stop mode. */
856 th->stop_requested = 0;
858 /* What is this a.out's name? */
859 printf_unfiltered (_("%s is executing new program: %s\n"),
860 target_pid_to_str (inferior_ptid),
863 /* We've followed the inferior through an exec. Therefore, the
864 inferior has essentially been killed & reborn. */
866 gdb_flush (gdb_stdout);
868 breakpoint_init_inferior (inf_execd);
870 if (gdb_sysroot && *gdb_sysroot)
872 char *name = alloca (strlen (gdb_sysroot)
873 + strlen (execd_pathname)
876 strcpy (name, gdb_sysroot);
877 strcat (name, execd_pathname);
878 execd_pathname = name;
881 /* Reset the shared library package. This ensures that we get a
882 shlib event when the child reaches "_start", at which point the
883 dld will have had a chance to initialize the child. */
884 /* Also, loading a symbol file below may trigger symbol lookups, and
885 we don't want those to be satisfied by the libraries of the
886 previous incarnation of this process. */
887 no_shared_libraries (NULL, 0);
889 if (follow_exec_mode_string == follow_exec_mode_new)
891 struct program_space *pspace;
893 /* The user wants to keep the old inferior and program spaces
894 around. Create a new fresh one, and switch to it. */
896 inf = add_inferior (current_inferior ()->pid);
897 pspace = add_program_space (maybe_new_address_space ());
898 inf->pspace = pspace;
899 inf->aspace = pspace->aspace;
901 exit_inferior_num_silent (current_inferior ()->num);
903 set_current_inferior (inf);
904 set_current_program_space (pspace);
908 /* The old description may no longer be fit for the new image.
909 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
910 old description; we'll read a new one below. No need to do
911 this on "follow-exec-mode new", as the old inferior stays
912 around (its description is later cleared/refetched on
914 target_clear_description ();
917 gdb_assert (current_program_space == inf->pspace);
919 /* That a.out is now the one to use. */
920 exec_file_attach (execd_pathname, 0);
922 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
923 (Position Independent Executable) main symbol file will get applied by
924 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
925 the breakpoints with the zero displacement. */
927 symbol_file_add (execd_pathname,
929 | SYMFILE_MAINLINE | SYMFILE_DEFER_BP_RESET),
932 if ((inf->symfile_flags & SYMFILE_NO_READ) == 0)
933 set_initial_language ();
935 /* If the target can specify a description, read it. Must do this
936 after flipping to the new executable (because the target supplied
937 description must be compatible with the executable's
938 architecture, and the old executable may e.g., be 32-bit, while
939 the new one 64-bit), and before anything involving memory or
941 target_find_description ();
943 solib_create_inferior_hook (0);
945 jit_inferior_created_hook ();
947 breakpoint_re_set ();
949 /* Reinsert all breakpoints. (Those which were symbolic have
950 been reset to the proper address in the new a.out, thanks
951 to symbol_file_command...). */
952 insert_breakpoints ();
954 /* The next resume of this inferior should bring it to the shlib
955 startup breakpoints. (If the user had also set bp's on
956 "main" from the old (parent) process, then they'll auto-
957 matically get reset there in the new process.). */
960 /* Non-zero if we just simulating a single-step. This is needed
961 because we cannot remove the breakpoints in the inferior process
962 until after the `wait' in `wait_for_inferior'. */
963 static int singlestep_breakpoints_inserted_p = 0;
965 /* The thread we inserted single-step breakpoints for. */
966 static ptid_t singlestep_ptid;
968 /* PC when we started this single-step. */
969 static CORE_ADDR singlestep_pc;
971 /* Info about an instruction that is being stepped over. Invalid if
974 struct step_over_info
976 /* The instruction's address space. */
977 struct address_space *aspace;
979 /* The instruction's address. */
983 /* The step-over info of the location that is being stepped over.
985 Note that with async/breakpoint always-inserted mode, a user might
986 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
987 being stepped over. As setting a new breakpoint inserts all
988 breakpoints, we need to make sure the breakpoint being stepped over
989 isn't inserted then. We do that by only clearing the step-over
990 info when the step-over is actually finished (or aborted).
992 Presently GDB can only step over one breakpoint at any given time.
993 Given threads that can't run code in the same address space as the
994 breakpoint's can't really miss the breakpoint, GDB could be taught
995 to step-over at most one breakpoint per address space (so this info
996 could move to the address space object if/when GDB is extended).
997 The set of breakpoints being stepped over will normally be much
998 smaller than the set of all breakpoints, so a flag in the
999 breakpoint location structure would be wasteful. A separate list
1000 also saves complexity and run-time, as otherwise we'd have to go
1001 through all breakpoint locations clearing their flag whenever we
1002 start a new sequence. Similar considerations weigh against storing
1003 this info in the thread object. Plus, not all step overs actually
1004 have breakpoint locations -- e.g., stepping past a single-step
1005 breakpoint, or stepping to complete a non-continuable
1007 static struct step_over_info step_over_info;
1009 /* Record the address of the breakpoint/instruction we're currently
1013 set_step_over_info (struct address_space *aspace, CORE_ADDR address)
1015 step_over_info.aspace = aspace;
1016 step_over_info.address = address;
1019 /* Called when we're not longer stepping over a breakpoint / an
1020 instruction, so all breakpoints are free to be (re)inserted. */
1023 clear_step_over_info (void)
1025 step_over_info.aspace = NULL;
1026 step_over_info.address = 0;
1032 stepping_past_instruction_at (struct address_space *aspace,
1035 return (step_over_info.aspace != NULL
1036 && breakpoint_address_match (aspace, address,
1037 step_over_info.aspace,
1038 step_over_info.address));
1042 /* Displaced stepping. */
1044 /* In non-stop debugging mode, we must take special care to manage
1045 breakpoints properly; in particular, the traditional strategy for
1046 stepping a thread past a breakpoint it has hit is unsuitable.
1047 'Displaced stepping' is a tactic for stepping one thread past a
1048 breakpoint it has hit while ensuring that other threads running
1049 concurrently will hit the breakpoint as they should.
1051 The traditional way to step a thread T off a breakpoint in a
1052 multi-threaded program in all-stop mode is as follows:
1054 a0) Initially, all threads are stopped, and breakpoints are not
1056 a1) We single-step T, leaving breakpoints uninserted.
1057 a2) We insert breakpoints, and resume all threads.
1059 In non-stop debugging, however, this strategy is unsuitable: we
1060 don't want to have to stop all threads in the system in order to
1061 continue or step T past a breakpoint. Instead, we use displaced
1064 n0) Initially, T is stopped, other threads are running, and
1065 breakpoints are inserted.
1066 n1) We copy the instruction "under" the breakpoint to a separate
1067 location, outside the main code stream, making any adjustments
1068 to the instruction, register, and memory state as directed by
1070 n2) We single-step T over the instruction at its new location.
1071 n3) We adjust the resulting register and memory state as directed
1072 by T's architecture. This includes resetting T's PC to point
1073 back into the main instruction stream.
1076 This approach depends on the following gdbarch methods:
1078 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1079 indicate where to copy the instruction, and how much space must
1080 be reserved there. We use these in step n1.
1082 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1083 address, and makes any necessary adjustments to the instruction,
1084 register contents, and memory. We use this in step n1.
1086 - gdbarch_displaced_step_fixup adjusts registers and memory after
1087 we have successfuly single-stepped the instruction, to yield the
1088 same effect the instruction would have had if we had executed it
1089 at its original address. We use this in step n3.
1091 - gdbarch_displaced_step_free_closure provides cleanup.
1093 The gdbarch_displaced_step_copy_insn and
1094 gdbarch_displaced_step_fixup functions must be written so that
1095 copying an instruction with gdbarch_displaced_step_copy_insn,
1096 single-stepping across the copied instruction, and then applying
1097 gdbarch_displaced_insn_fixup should have the same effects on the
1098 thread's memory and registers as stepping the instruction in place
1099 would have. Exactly which responsibilities fall to the copy and
1100 which fall to the fixup is up to the author of those functions.
1102 See the comments in gdbarch.sh for details.
1104 Note that displaced stepping and software single-step cannot
1105 currently be used in combination, although with some care I think
1106 they could be made to. Software single-step works by placing
1107 breakpoints on all possible subsequent instructions; if the
1108 displaced instruction is a PC-relative jump, those breakpoints
1109 could fall in very strange places --- on pages that aren't
1110 executable, or at addresses that are not proper instruction
1111 boundaries. (We do generally let other threads run while we wait
1112 to hit the software single-step breakpoint, and they might
1113 encounter such a corrupted instruction.) One way to work around
1114 this would be to have gdbarch_displaced_step_copy_insn fully
1115 simulate the effect of PC-relative instructions (and return NULL)
1116 on architectures that use software single-stepping.
1118 In non-stop mode, we can have independent and simultaneous step
1119 requests, so more than one thread may need to simultaneously step
1120 over a breakpoint. The current implementation assumes there is
1121 only one scratch space per process. In this case, we have to
1122 serialize access to the scratch space. If thread A wants to step
1123 over a breakpoint, but we are currently waiting for some other
1124 thread to complete a displaced step, we leave thread A stopped and
1125 place it in the displaced_step_request_queue. Whenever a displaced
1126 step finishes, we pick the next thread in the queue and start a new
1127 displaced step operation on it. See displaced_step_prepare and
1128 displaced_step_fixup for details. */
1130 struct displaced_step_request
1133 struct displaced_step_request *next;
1136 /* Per-inferior displaced stepping state. */
1137 struct displaced_step_inferior_state
1139 /* Pointer to next in linked list. */
1140 struct displaced_step_inferior_state *next;
1142 /* The process this displaced step state refers to. */
1145 /* A queue of pending displaced stepping requests. One entry per
1146 thread that needs to do a displaced step. */
1147 struct displaced_step_request *step_request_queue;
1149 /* If this is not null_ptid, this is the thread carrying out a
1150 displaced single-step in process PID. This thread's state will
1151 require fixing up once it has completed its step. */
1154 /* The architecture the thread had when we stepped it. */
1155 struct gdbarch *step_gdbarch;
1157 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1158 for post-step cleanup. */
1159 struct displaced_step_closure *step_closure;
1161 /* The address of the original instruction, and the copy we
1163 CORE_ADDR step_original, step_copy;
1165 /* Saved contents of copy area. */
1166 gdb_byte *step_saved_copy;
1169 /* The list of states of processes involved in displaced stepping
1171 static struct displaced_step_inferior_state *displaced_step_inferior_states;
1173 /* Get the displaced stepping state of process PID. */
1175 static struct displaced_step_inferior_state *
1176 get_displaced_stepping_state (int pid)
1178 struct displaced_step_inferior_state *state;
1180 for (state = displaced_step_inferior_states;
1182 state = state->next)
1183 if (state->pid == pid)
1189 /* Add a new displaced stepping state for process PID to the displaced
1190 stepping state list, or return a pointer to an already existing
1191 entry, if it already exists. Never returns NULL. */
1193 static struct displaced_step_inferior_state *
1194 add_displaced_stepping_state (int pid)
1196 struct displaced_step_inferior_state *state;
1198 for (state = displaced_step_inferior_states;
1200 state = state->next)
1201 if (state->pid == pid)
1204 state = xcalloc (1, sizeof (*state));
1206 state->next = displaced_step_inferior_states;
1207 displaced_step_inferior_states = state;
1212 /* If inferior is in displaced stepping, and ADDR equals to starting address
1213 of copy area, return corresponding displaced_step_closure. Otherwise,
1216 struct displaced_step_closure*
1217 get_displaced_step_closure_by_addr (CORE_ADDR addr)
1219 struct displaced_step_inferior_state *displaced
1220 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
1222 /* If checking the mode of displaced instruction in copy area. */
1223 if (displaced && !ptid_equal (displaced->step_ptid, null_ptid)
1224 && (displaced->step_copy == addr))
1225 return displaced->step_closure;
1230 /* Remove the displaced stepping state of process PID. */
1233 remove_displaced_stepping_state (int pid)
1235 struct displaced_step_inferior_state *it, **prev_next_p;
1237 gdb_assert (pid != 0);
1239 it = displaced_step_inferior_states;
1240 prev_next_p = &displaced_step_inferior_states;
1245 *prev_next_p = it->next;
1250 prev_next_p = &it->next;
1256 infrun_inferior_exit (struct inferior *inf)
1258 remove_displaced_stepping_state (inf->pid);
1261 /* If ON, and the architecture supports it, GDB will use displaced
1262 stepping to step over breakpoints. If OFF, or if the architecture
1263 doesn't support it, GDB will instead use the traditional
1264 hold-and-step approach. If AUTO (which is the default), GDB will
1265 decide which technique to use to step over breakpoints depending on
1266 which of all-stop or non-stop mode is active --- displaced stepping
1267 in non-stop mode; hold-and-step in all-stop mode. */
1269 static enum auto_boolean can_use_displaced_stepping = AUTO_BOOLEAN_AUTO;
1272 show_can_use_displaced_stepping (struct ui_file *file, int from_tty,
1273 struct cmd_list_element *c,
1276 if (can_use_displaced_stepping == AUTO_BOOLEAN_AUTO)
1277 fprintf_filtered (file,
1278 _("Debugger's willingness to use displaced stepping "
1279 "to step over breakpoints is %s (currently %s).\n"),
1280 value, non_stop ? "on" : "off");
1282 fprintf_filtered (file,
1283 _("Debugger's willingness to use displaced stepping "
1284 "to step over breakpoints is %s.\n"), value);
1287 /* Return non-zero if displaced stepping can/should be used to step
1288 over breakpoints. */
1291 use_displaced_stepping (struct gdbarch *gdbarch)
1293 return (((can_use_displaced_stepping == AUTO_BOOLEAN_AUTO && non_stop)
1294 || can_use_displaced_stepping == AUTO_BOOLEAN_TRUE)
1295 && gdbarch_displaced_step_copy_insn_p (gdbarch)
1296 && find_record_target () == NULL);
1299 /* Clean out any stray displaced stepping state. */
1301 displaced_step_clear (struct displaced_step_inferior_state *displaced)
1303 /* Indicate that there is no cleanup pending. */
1304 displaced->step_ptid = null_ptid;
1306 if (displaced->step_closure)
1308 gdbarch_displaced_step_free_closure (displaced->step_gdbarch,
1309 displaced->step_closure);
1310 displaced->step_closure = NULL;
1315 displaced_step_clear_cleanup (void *arg)
1317 struct displaced_step_inferior_state *state = arg;
1319 displaced_step_clear (state);
1322 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1324 displaced_step_dump_bytes (struct ui_file *file,
1325 const gdb_byte *buf,
1330 for (i = 0; i < len; i++)
1331 fprintf_unfiltered (file, "%02x ", buf[i]);
1332 fputs_unfiltered ("\n", file);
1335 /* Prepare to single-step, using displaced stepping.
1337 Note that we cannot use displaced stepping when we have a signal to
1338 deliver. If we have a signal to deliver and an instruction to step
1339 over, then after the step, there will be no indication from the
1340 target whether the thread entered a signal handler or ignored the
1341 signal and stepped over the instruction successfully --- both cases
1342 result in a simple SIGTRAP. In the first case we mustn't do a
1343 fixup, and in the second case we must --- but we can't tell which.
1344 Comments in the code for 'random signals' in handle_inferior_event
1345 explain how we handle this case instead.
1347 Returns 1 if preparing was successful -- this thread is going to be
1348 stepped now; or 0 if displaced stepping this thread got queued. */
1350 displaced_step_prepare (ptid_t ptid)
1352 struct cleanup *old_cleanups, *ignore_cleanups;
1353 struct thread_info *tp = find_thread_ptid (ptid);
1354 struct regcache *regcache = get_thread_regcache (ptid);
1355 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1356 CORE_ADDR original, copy;
1358 struct displaced_step_closure *closure;
1359 struct displaced_step_inferior_state *displaced;
1362 /* We should never reach this function if the architecture does not
1363 support displaced stepping. */
1364 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch));
1366 /* Disable range stepping while executing in the scratch pad. We
1367 want a single-step even if executing the displaced instruction in
1368 the scratch buffer lands within the stepping range (e.g., a
1370 tp->control.may_range_step = 0;
1372 /* We have to displaced step one thread at a time, as we only have
1373 access to a single scratch space per inferior. */
1375 displaced = add_displaced_stepping_state (ptid_get_pid (ptid));
1377 if (!ptid_equal (displaced->step_ptid, null_ptid))
1379 /* Already waiting for a displaced step to finish. Defer this
1380 request and place in queue. */
1381 struct displaced_step_request *req, *new_req;
1383 if (debug_displaced)
1384 fprintf_unfiltered (gdb_stdlog,
1385 "displaced: defering step of %s\n",
1386 target_pid_to_str (ptid));
1388 new_req = xmalloc (sizeof (*new_req));
1389 new_req->ptid = ptid;
1390 new_req->next = NULL;
1392 if (displaced->step_request_queue)
1394 for (req = displaced->step_request_queue;
1398 req->next = new_req;
1401 displaced->step_request_queue = new_req;
1407 if (debug_displaced)
1408 fprintf_unfiltered (gdb_stdlog,
1409 "displaced: stepping %s now\n",
1410 target_pid_to_str (ptid));
1413 displaced_step_clear (displaced);
1415 old_cleanups = save_inferior_ptid ();
1416 inferior_ptid = ptid;
1418 original = regcache_read_pc (regcache);
1420 copy = gdbarch_displaced_step_location (gdbarch);
1421 len = gdbarch_max_insn_length (gdbarch);
1423 /* Save the original contents of the copy area. */
1424 displaced->step_saved_copy = xmalloc (len);
1425 ignore_cleanups = make_cleanup (free_current_contents,
1426 &displaced->step_saved_copy);
1427 status = target_read_memory (copy, displaced->step_saved_copy, len);
1429 throw_error (MEMORY_ERROR,
1430 _("Error accessing memory address %s (%s) for "
1431 "displaced-stepping scratch space."),
1432 paddress (gdbarch, copy), safe_strerror (status));
1433 if (debug_displaced)
1435 fprintf_unfiltered (gdb_stdlog, "displaced: saved %s: ",
1436 paddress (gdbarch, copy));
1437 displaced_step_dump_bytes (gdb_stdlog,
1438 displaced->step_saved_copy,
1442 closure = gdbarch_displaced_step_copy_insn (gdbarch,
1443 original, copy, regcache);
1445 /* We don't support the fully-simulated case at present. */
1446 gdb_assert (closure);
1448 /* Save the information we need to fix things up if the step
1450 displaced->step_ptid = ptid;
1451 displaced->step_gdbarch = gdbarch;
1452 displaced->step_closure = closure;
1453 displaced->step_original = original;
1454 displaced->step_copy = copy;
1456 make_cleanup (displaced_step_clear_cleanup, displaced);
1458 /* Resume execution at the copy. */
1459 regcache_write_pc (regcache, copy);
1461 discard_cleanups (ignore_cleanups);
1463 do_cleanups (old_cleanups);
1465 if (debug_displaced)
1466 fprintf_unfiltered (gdb_stdlog, "displaced: displaced pc to %s\n",
1467 paddress (gdbarch, copy));
1473 write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr,
1474 const gdb_byte *myaddr, int len)
1476 struct cleanup *ptid_cleanup = save_inferior_ptid ();
1478 inferior_ptid = ptid;
1479 write_memory (memaddr, myaddr, len);
1480 do_cleanups (ptid_cleanup);
1483 /* Restore the contents of the copy area for thread PTID. */
1486 displaced_step_restore (struct displaced_step_inferior_state *displaced,
1489 ULONGEST len = gdbarch_max_insn_length (displaced->step_gdbarch);
1491 write_memory_ptid (ptid, displaced->step_copy,
1492 displaced->step_saved_copy, len);
1493 if (debug_displaced)
1494 fprintf_unfiltered (gdb_stdlog, "displaced: restored %s %s\n",
1495 target_pid_to_str (ptid),
1496 paddress (displaced->step_gdbarch,
1497 displaced->step_copy));
1501 displaced_step_fixup (ptid_t event_ptid, enum gdb_signal signal)
1503 struct cleanup *old_cleanups;
1504 struct displaced_step_inferior_state *displaced
1505 = get_displaced_stepping_state (ptid_get_pid (event_ptid));
1507 /* Was any thread of this process doing a displaced step? */
1508 if (displaced == NULL)
1511 /* Was this event for the pid we displaced? */
1512 if (ptid_equal (displaced->step_ptid, null_ptid)
1513 || ! ptid_equal (displaced->step_ptid, event_ptid))
1516 old_cleanups = make_cleanup (displaced_step_clear_cleanup, displaced);
1518 displaced_step_restore (displaced, displaced->step_ptid);
1520 /* Did the instruction complete successfully? */
1521 if (signal == GDB_SIGNAL_TRAP)
1523 /* Fix up the resulting state. */
1524 gdbarch_displaced_step_fixup (displaced->step_gdbarch,
1525 displaced->step_closure,
1526 displaced->step_original,
1527 displaced->step_copy,
1528 get_thread_regcache (displaced->step_ptid));
1532 /* Since the instruction didn't complete, all we can do is
1534 struct regcache *regcache = get_thread_regcache (event_ptid);
1535 CORE_ADDR pc = regcache_read_pc (regcache);
1537 pc = displaced->step_original + (pc - displaced->step_copy);
1538 regcache_write_pc (regcache, pc);
1541 do_cleanups (old_cleanups);
1543 displaced->step_ptid = null_ptid;
1545 /* Are there any pending displaced stepping requests? If so, run
1546 one now. Leave the state object around, since we're likely to
1547 need it again soon. */
1548 while (displaced->step_request_queue)
1550 struct displaced_step_request *head;
1552 struct regcache *regcache;
1553 struct gdbarch *gdbarch;
1554 CORE_ADDR actual_pc;
1555 struct address_space *aspace;
1557 head = displaced->step_request_queue;
1559 displaced->step_request_queue = head->next;
1562 context_switch (ptid);
1564 regcache = get_thread_regcache (ptid);
1565 actual_pc = regcache_read_pc (regcache);
1566 aspace = get_regcache_aspace (regcache);
1568 if (breakpoint_here_p (aspace, actual_pc))
1570 if (debug_displaced)
1571 fprintf_unfiltered (gdb_stdlog,
1572 "displaced: stepping queued %s now\n",
1573 target_pid_to_str (ptid));
1575 displaced_step_prepare (ptid);
1577 gdbarch = get_regcache_arch (regcache);
1579 if (debug_displaced)
1581 CORE_ADDR actual_pc = regcache_read_pc (regcache);
1584 fprintf_unfiltered (gdb_stdlog, "displaced: run %s: ",
1585 paddress (gdbarch, actual_pc));
1586 read_memory (actual_pc, buf, sizeof (buf));
1587 displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
1590 if (gdbarch_displaced_step_hw_singlestep (gdbarch,
1591 displaced->step_closure))
1592 target_resume (ptid, 1, GDB_SIGNAL_0);
1594 target_resume (ptid, 0, GDB_SIGNAL_0);
1596 /* Done, we're stepping a thread. */
1602 struct thread_info *tp = inferior_thread ();
1604 /* The breakpoint we were sitting under has since been
1606 tp->control.trap_expected = 0;
1608 /* Go back to what we were trying to do. */
1609 step = currently_stepping (tp);
1611 if (debug_displaced)
1612 fprintf_unfiltered (gdb_stdlog,
1613 "displaced: breakpoint is gone: %s, step(%d)\n",
1614 target_pid_to_str (tp->ptid), step);
1616 target_resume (ptid, step, GDB_SIGNAL_0);
1617 tp->suspend.stop_signal = GDB_SIGNAL_0;
1619 /* This request was discarded. See if there's any other
1620 thread waiting for its turn. */
1625 /* Update global variables holding ptids to hold NEW_PTID if they were
1626 holding OLD_PTID. */
1628 infrun_thread_ptid_changed (ptid_t old_ptid, ptid_t new_ptid)
1630 struct displaced_step_request *it;
1631 struct displaced_step_inferior_state *displaced;
1633 if (ptid_equal (inferior_ptid, old_ptid))
1634 inferior_ptid = new_ptid;
1636 if (ptid_equal (singlestep_ptid, old_ptid))
1637 singlestep_ptid = new_ptid;
1639 for (displaced = displaced_step_inferior_states;
1641 displaced = displaced->next)
1643 if (ptid_equal (displaced->step_ptid, old_ptid))
1644 displaced->step_ptid = new_ptid;
1646 for (it = displaced->step_request_queue; it; it = it->next)
1647 if (ptid_equal (it->ptid, old_ptid))
1648 it->ptid = new_ptid;
1655 /* Things to clean up if we QUIT out of resume (). */
1657 resume_cleanups (void *ignore)
1662 static const char schedlock_off[] = "off";
1663 static const char schedlock_on[] = "on";
1664 static const char schedlock_step[] = "step";
1665 static const char *const scheduler_enums[] = {
1671 static const char *scheduler_mode = schedlock_off;
1673 show_scheduler_mode (struct ui_file *file, int from_tty,
1674 struct cmd_list_element *c, const char *value)
1676 fprintf_filtered (file,
1677 _("Mode for locking scheduler "
1678 "during execution is \"%s\".\n"),
1683 set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
1685 if (!target_can_lock_scheduler)
1687 scheduler_mode = schedlock_off;
1688 error (_("Target '%s' cannot support this command."), target_shortname);
1692 /* True if execution commands resume all threads of all processes by
1693 default; otherwise, resume only threads of the current inferior
1695 int sched_multi = 0;
1697 /* Try to setup for software single stepping over the specified location.
1698 Return 1 if target_resume() should use hardware single step.
1700 GDBARCH the current gdbarch.
1701 PC the location to step over. */
1704 maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc)
1708 if (execution_direction == EXEC_FORWARD
1709 && gdbarch_software_single_step_p (gdbarch)
1710 && gdbarch_software_single_step (gdbarch, get_current_frame ()))
1713 /* Do not pull these breakpoints until after a `wait' in
1714 `wait_for_inferior'. */
1715 singlestep_breakpoints_inserted_p = 1;
1716 singlestep_ptid = inferior_ptid;
1723 user_visible_resume_ptid (int step)
1725 /* By default, resume all threads of all processes. */
1726 ptid_t resume_ptid = RESUME_ALL;
1728 /* Maybe resume only all threads of the current process. */
1729 if (!sched_multi && target_supports_multi_process ())
1731 resume_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
1734 /* Maybe resume a single thread after all. */
1737 /* With non-stop mode on, threads are always handled
1739 resume_ptid = inferior_ptid;
1741 else if ((scheduler_mode == schedlock_on)
1742 || (scheduler_mode == schedlock_step && step))
1744 /* User-settable 'scheduler' mode requires solo thread resume. */
1745 resume_ptid = inferior_ptid;
1748 /* We may actually resume fewer threads at first, e.g., if a thread
1749 is stopped at a breakpoint that needs stepping-off, but that
1750 should not be visible to the user/frontend, and neither should
1751 the frontend/user be allowed to proceed any of the threads that
1752 happen to be stopped for internal run control handling, if a
1753 previous command wanted them resumed. */
1757 /* Resume the inferior, but allow a QUIT. This is useful if the user
1758 wants to interrupt some lengthy single-stepping operation
1759 (for child processes, the SIGINT goes to the inferior, and so
1760 we get a SIGINT random_signal, but for remote debugging and perhaps
1761 other targets, that's not true).
1763 STEP nonzero if we should step (zero to continue instead).
1764 SIG is the signal to give the inferior (zero for none). */
1766 resume (int step, enum gdb_signal sig)
1768 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
1769 struct regcache *regcache = get_current_regcache ();
1770 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1771 struct thread_info *tp = inferior_thread ();
1772 CORE_ADDR pc = regcache_read_pc (regcache);
1773 struct address_space *aspace = get_regcache_aspace (regcache);
1775 /* From here on, this represents the caller's step vs continue
1776 request, while STEP represents what we'll actually request the
1777 target to do. STEP can decay from a step to a continue, if e.g.,
1778 we need to implement single-stepping with breakpoints (software
1779 single-step). When deciding whether "set scheduler-locking step"
1780 applies, it's the callers intention that counts. */
1781 const int entry_step = step;
1785 if (current_inferior ()->waiting_for_vfork_done)
1787 /* Don't try to single-step a vfork parent that is waiting for
1788 the child to get out of the shared memory region (by exec'ing
1789 or exiting). This is particularly important on software
1790 single-step archs, as the child process would trip on the
1791 software single step breakpoint inserted for the parent
1792 process. Since the parent will not actually execute any
1793 instruction until the child is out of the shared region (such
1794 are vfork's semantics), it is safe to simply continue it.
1795 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
1796 the parent, and tell it to `keep_going', which automatically
1797 re-sets it stepping. */
1799 fprintf_unfiltered (gdb_stdlog,
1800 "infrun: resume : clear step\n");
1805 fprintf_unfiltered (gdb_stdlog,
1806 "infrun: resume (step=%d, signal=%s), "
1807 "trap_expected=%d, current thread [%s] at %s\n",
1808 step, gdb_signal_to_symbol_string (sig),
1809 tp->control.trap_expected,
1810 target_pid_to_str (inferior_ptid),
1811 paddress (gdbarch, pc));
1813 /* Normally, by the time we reach `resume', the breakpoints are either
1814 removed or inserted, as appropriate. The exception is if we're sitting
1815 at a permanent breakpoint; we need to step over it, but permanent
1816 breakpoints can't be removed. So we have to test for it here. */
1817 if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here)
1819 if (gdbarch_skip_permanent_breakpoint_p (gdbarch))
1820 gdbarch_skip_permanent_breakpoint (gdbarch, regcache);
1823 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1824 how to step past a permanent breakpoint on this architecture. Try using\n\
1825 a command like `return' or `jump' to continue execution."));
1828 /* If we have a breakpoint to step over, make sure to do a single
1829 step only. Same if we have software watchpoints. */
1830 if (tp->control.trap_expected || bpstat_should_step ())
1831 tp->control.may_range_step = 0;
1833 /* If enabled, step over breakpoints by executing a copy of the
1834 instruction at a different address.
1836 We can't use displaced stepping when we have a signal to deliver;
1837 the comments for displaced_step_prepare explain why. The
1838 comments in the handle_inferior event for dealing with 'random
1839 signals' explain what we do instead.
1841 We can't use displaced stepping when we are waiting for vfork_done
1842 event, displaced stepping breaks the vfork child similarly as single
1843 step software breakpoint. */
1844 if (use_displaced_stepping (gdbarch)
1845 && (tp->control.trap_expected
1846 || (step && gdbarch_software_single_step_p (gdbarch)))
1847 && sig == GDB_SIGNAL_0
1848 && !current_inferior ()->waiting_for_vfork_done)
1850 struct displaced_step_inferior_state *displaced;
1852 if (!displaced_step_prepare (inferior_ptid))
1854 /* Got placed in displaced stepping queue. Will be resumed
1855 later when all the currently queued displaced stepping
1856 requests finish. The thread is not executing at this
1857 point, and the call to set_executing will be made later.
1858 But we need to call set_running here, since from the
1859 user/frontend's point of view, threads were set running.
1860 Unless we're calling an inferior function, as in that
1861 case we pretend the inferior doesn't run at all. */
1862 if (!tp->control.in_infcall)
1863 set_running (user_visible_resume_ptid (entry_step), 1);
1864 discard_cleanups (old_cleanups);
1868 /* Update pc to reflect the new address from which we will execute
1869 instructions due to displaced stepping. */
1870 pc = regcache_read_pc (get_thread_regcache (inferior_ptid));
1872 displaced = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
1873 step = gdbarch_displaced_step_hw_singlestep (gdbarch,
1874 displaced->step_closure);
1877 /* Do we need to do it the hard way, w/temp breakpoints? */
1879 step = maybe_software_singlestep (gdbarch, pc);
1881 /* Currently, our software single-step implementation leads to different
1882 results than hardware single-stepping in one situation: when stepping
1883 into delivering a signal which has an associated signal handler,
1884 hardware single-step will stop at the first instruction of the handler,
1885 while software single-step will simply skip execution of the handler.
1887 For now, this difference in behavior is accepted since there is no
1888 easy way to actually implement single-stepping into a signal handler
1889 without kernel support.
1891 However, there is one scenario where this difference leads to follow-on
1892 problems: if we're stepping off a breakpoint by removing all breakpoints
1893 and then single-stepping. In this case, the software single-step
1894 behavior means that even if there is a *breakpoint* in the signal
1895 handler, GDB still would not stop.
1897 Fortunately, we can at least fix this particular issue. We detect
1898 here the case where we are about to deliver a signal while software
1899 single-stepping with breakpoints removed. In this situation, we
1900 revert the decisions to remove all breakpoints and insert single-
1901 step breakpoints, and instead we install a step-resume breakpoint
1902 at the current address, deliver the signal without stepping, and
1903 once we arrive back at the step-resume breakpoint, actually step
1904 over the breakpoint we originally wanted to step over. */
1905 if (singlestep_breakpoints_inserted_p
1906 && tp->control.trap_expected && sig != GDB_SIGNAL_0)
1908 /* If we have nested signals or a pending signal is delivered
1909 immediately after a handler returns, might might already have
1910 a step-resume breakpoint set on the earlier handler. We cannot
1911 set another step-resume breakpoint; just continue on until the
1912 original breakpoint is hit. */
1913 if (tp->control.step_resume_breakpoint == NULL)
1915 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
1916 tp->step_after_step_resume_breakpoint = 1;
1919 remove_single_step_breakpoints ();
1920 singlestep_breakpoints_inserted_p = 0;
1922 clear_step_over_info ();
1923 tp->control.trap_expected = 0;
1925 insert_breakpoints ();
1928 /* If STEP is set, it's a request to use hardware stepping
1929 facilities. But in that case, we should never
1930 use singlestep breakpoint. */
1931 gdb_assert (!(singlestep_breakpoints_inserted_p && step));
1933 /* Decide the set of threads to ask the target to resume. Start
1934 by assuming everything will be resumed, than narrow the set
1935 by applying increasingly restricting conditions. */
1936 resume_ptid = user_visible_resume_ptid (entry_step);
1938 /* Even if RESUME_PTID is a wildcard, and we end up resuming less
1939 (e.g., we might need to step over a breakpoint), from the
1940 user/frontend's point of view, all threads in RESUME_PTID are now
1941 running. Unless we're calling an inferior function, as in that
1942 case pretend we inferior doesn't run at all. */
1943 if (!tp->control.in_infcall)
1944 set_running (resume_ptid, 1);
1946 /* Maybe resume a single thread after all. */
1947 if ((step || singlestep_breakpoints_inserted_p)
1948 && tp->control.trap_expected)
1950 /* We're allowing a thread to run past a breakpoint it has
1951 hit, by single-stepping the thread with the breakpoint
1952 removed. In which case, we need to single-step only this
1953 thread, and keep others stopped, as they can miss this
1954 breakpoint if allowed to run. */
1955 resume_ptid = inferior_ptid;
1958 if (gdbarch_cannot_step_breakpoint (gdbarch))
1960 /* Most targets can step a breakpoint instruction, thus
1961 executing it normally. But if this one cannot, just
1962 continue and we will hit it anyway. */
1963 if (step && breakpoint_inserted_here_p (aspace, pc))
1968 && use_displaced_stepping (gdbarch)
1969 && tp->control.trap_expected)
1971 struct regcache *resume_regcache = get_thread_regcache (resume_ptid);
1972 struct gdbarch *resume_gdbarch = get_regcache_arch (resume_regcache);
1973 CORE_ADDR actual_pc = regcache_read_pc (resume_regcache);
1976 fprintf_unfiltered (gdb_stdlog, "displaced: run %s: ",
1977 paddress (resume_gdbarch, actual_pc));
1978 read_memory (actual_pc, buf, sizeof (buf));
1979 displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
1982 if (tp->control.may_range_step)
1984 /* If we're resuming a thread with the PC out of the step
1985 range, then we're doing some nested/finer run control
1986 operation, like stepping the thread out of the dynamic
1987 linker or the displaced stepping scratch pad. We
1988 shouldn't have allowed a range step then. */
1989 gdb_assert (pc_in_thread_step_range (pc, tp));
1992 /* Install inferior's terminal modes. */
1993 target_terminal_inferior ();
1995 /* Avoid confusing the next resume, if the next stop/resume
1996 happens to apply to another thread. */
1997 tp->suspend.stop_signal = GDB_SIGNAL_0;
1999 /* Advise target which signals may be handled silently. If we have
2000 removed breakpoints because we are stepping over one (which can
2001 happen only if we are not using displaced stepping), we need to
2002 receive all signals to avoid accidentally skipping a breakpoint
2003 during execution of a signal handler. */
2004 if ((step || singlestep_breakpoints_inserted_p)
2005 && tp->control.trap_expected
2006 && !use_displaced_stepping (gdbarch))
2007 target_pass_signals (0, NULL);
2009 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
2011 target_resume (resume_ptid, step, sig);
2013 discard_cleanups (old_cleanups);
2018 /* Clear out all variables saying what to do when inferior is continued.
2019 First do this, then set the ones you want, then call `proceed'. */
2022 clear_proceed_status_thread (struct thread_info *tp)
2025 fprintf_unfiltered (gdb_stdlog,
2026 "infrun: clear_proceed_status_thread (%s)\n",
2027 target_pid_to_str (tp->ptid));
2029 /* If this signal should not be seen by program, give it zero.
2030 Used for debugging signals. */
2031 if (!signal_pass_state (tp->suspend.stop_signal))
2032 tp->suspend.stop_signal = GDB_SIGNAL_0;
2034 tp->control.trap_expected = 0;
2035 tp->control.step_range_start = 0;
2036 tp->control.step_range_end = 0;
2037 tp->control.may_range_step = 0;
2038 tp->control.step_frame_id = null_frame_id;
2039 tp->control.step_stack_frame_id = null_frame_id;
2040 tp->control.step_over_calls = STEP_OVER_UNDEBUGGABLE;
2041 tp->stop_requested = 0;
2043 tp->control.stop_step = 0;
2045 tp->control.proceed_to_finish = 0;
2047 tp->control.command_interp = NULL;
2049 /* Discard any remaining commands or status from previous stop. */
2050 bpstat_clear (&tp->control.stop_bpstat);
2054 clear_proceed_status (int step)
2058 struct thread_info *tp;
2061 resume_ptid = user_visible_resume_ptid (step);
2063 /* In all-stop mode, delete the per-thread status of all threads
2064 we're about to resume, implicitly and explicitly. */
2065 ALL_NON_EXITED_THREADS (tp)
2067 if (!ptid_match (tp->ptid, resume_ptid))
2069 clear_proceed_status_thread (tp);
2073 if (!ptid_equal (inferior_ptid, null_ptid))
2075 struct inferior *inferior;
2079 /* If in non-stop mode, only delete the per-thread status of
2080 the current thread. */
2081 clear_proceed_status_thread (inferior_thread ());
2084 inferior = current_inferior ();
2085 inferior->control.stop_soon = NO_STOP_QUIETLY;
2088 stop_after_trap = 0;
2090 clear_step_over_info ();
2092 observer_notify_about_to_proceed ();
2096 regcache_xfree (stop_registers);
2097 stop_registers = NULL;
2101 /* Returns true if TP is still stopped at a breakpoint that needs
2102 stepping-over in order to make progress. If the breakpoint is gone
2103 meanwhile, we can skip the whole step-over dance. */
2106 thread_still_needs_step_over (struct thread_info *tp)
2108 if (tp->stepping_over_breakpoint)
2110 struct regcache *regcache = get_thread_regcache (tp->ptid);
2112 if (breakpoint_here_p (get_regcache_aspace (regcache),
2113 regcache_read_pc (regcache)))
2116 tp->stepping_over_breakpoint = 0;
2122 /* Returns true if scheduler locking applies. STEP indicates whether
2123 we're about to do a step/next-like command to a thread. */
2126 schedlock_applies (int step)
2128 return (scheduler_mode == schedlock_on
2129 || (scheduler_mode == schedlock_step
2133 /* Look a thread other than EXCEPT that has previously reported a
2134 breakpoint event, and thus needs a step-over in order to make
2135 progress. Returns NULL is none is found. STEP indicates whether
2136 we're about to step the current thread, in order to decide whether
2137 "set scheduler-locking step" applies. */
2139 static struct thread_info *
2140 find_thread_needs_step_over (int step, struct thread_info *except)
2142 struct thread_info *tp, *current;
2144 /* With non-stop mode on, threads are always handled individually. */
2145 gdb_assert (! non_stop);
2147 current = inferior_thread ();
2149 /* If scheduler locking applies, we can avoid iterating over all
2151 if (schedlock_applies (step))
2153 if (except != current
2154 && thread_still_needs_step_over (current))
2160 ALL_NON_EXITED_THREADS (tp)
2162 /* Ignore the EXCEPT thread. */
2165 /* Ignore threads of processes we're not resuming. */
2167 && ptid_get_pid (tp->ptid) != ptid_get_pid (inferior_ptid))
2170 if (thread_still_needs_step_over (tp))
2177 /* Basic routine for continuing the program in various fashions.
2179 ADDR is the address to resume at, or -1 for resume where stopped.
2180 SIGGNAL is the signal to give it, or 0 for none,
2181 or -1 for act according to how it stopped.
2182 STEP is nonzero if should trap after one instruction.
2183 -1 means return after that and print nothing.
2184 You should probably set various step_... variables
2185 before calling here, if you are stepping.
2187 You should call clear_proceed_status before calling proceed. */
2190 proceed (CORE_ADDR addr, enum gdb_signal siggnal, int step)
2192 struct regcache *regcache;
2193 struct gdbarch *gdbarch;
2194 struct thread_info *tp;
2196 struct address_space *aspace;
2198 /* If we're stopped at a fork/vfork, follow the branch set by the
2199 "set follow-fork-mode" command; otherwise, we'll just proceed
2200 resuming the current thread. */
2201 if (!follow_fork ())
2203 /* The target for some reason decided not to resume. */
2205 if (target_can_async_p ())
2206 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
2210 /* We'll update this if & when we switch to a new thread. */
2211 previous_inferior_ptid = inferior_ptid;
2213 regcache = get_current_regcache ();
2214 gdbarch = get_regcache_arch (regcache);
2215 aspace = get_regcache_aspace (regcache);
2216 pc = regcache_read_pc (regcache);
2217 tp = inferior_thread ();
2220 step_start_function = find_pc_function (pc);
2222 stop_after_trap = 1;
2224 /* Fill in with reasonable starting values. */
2225 init_thread_stepping_state (tp);
2227 if (addr == (CORE_ADDR) -1)
2229 if (pc == stop_pc && breakpoint_here_p (aspace, pc)
2230 && execution_direction != EXEC_REVERSE)
2231 /* There is a breakpoint at the address we will resume at,
2232 step one instruction before inserting breakpoints so that
2233 we do not stop right away (and report a second hit at this
2236 Note, we don't do this in reverse, because we won't
2237 actually be executing the breakpoint insn anyway.
2238 We'll be (un-)executing the previous instruction. */
2239 tp->stepping_over_breakpoint = 1;
2240 else if (gdbarch_single_step_through_delay_p (gdbarch)
2241 && gdbarch_single_step_through_delay (gdbarch,
2242 get_current_frame ()))
2243 /* We stepped onto an instruction that needs to be stepped
2244 again before re-inserting the breakpoint, do so. */
2245 tp->stepping_over_breakpoint = 1;
2249 regcache_write_pc (regcache, addr);
2252 if (siggnal != GDB_SIGNAL_DEFAULT)
2253 tp->suspend.stop_signal = siggnal;
2255 /* Record the interpreter that issued the execution command that
2256 caused this thread to resume. If the top level interpreter is
2257 MI/async, and the execution command was a CLI command
2258 (next/step/etc.), we'll want to print stop event output to the MI
2259 console channel (the stepped-to line, etc.), as if the user
2260 entered the execution command on a real GDB console. */
2261 inferior_thread ()->control.command_interp = command_interp ();
2264 fprintf_unfiltered (gdb_stdlog,
2265 "infrun: proceed (addr=%s, signal=%s, step=%d)\n",
2266 paddress (gdbarch, addr),
2267 gdb_signal_to_symbol_string (siggnal), step);
2270 /* In non-stop, each thread is handled individually. The context
2271 must already be set to the right thread here. */
2275 struct thread_info *step_over;
2277 /* In a multi-threaded task we may select another thread and
2278 then continue or step.
2280 But if the old thread was stopped at a breakpoint, it will
2281 immediately cause another breakpoint stop without any
2282 execution (i.e. it will report a breakpoint hit incorrectly).
2283 So we must step over it first.
2285 Look for a thread other than the current (TP) that reported a
2286 breakpoint hit and hasn't been resumed yet since. */
2287 step_over = find_thread_needs_step_over (step, tp);
2288 if (step_over != NULL)
2291 fprintf_unfiltered (gdb_stdlog,
2292 "infrun: need to step-over [%s] first\n",
2293 target_pid_to_str (step_over->ptid));
2295 /* Store the prev_pc for the stepping thread too, needed by
2296 switch_back_to_stepping thread. */
2297 tp->prev_pc = regcache_read_pc (get_current_regcache ());
2298 switch_to_thread (step_over->ptid);
2303 /* If we need to step over a breakpoint, and we're not using
2304 displaced stepping to do so, insert all breakpoints (watchpoints,
2305 etc.) but the one we're stepping over, step one instruction, and
2306 then re-insert the breakpoint when that step is finished. */
2307 if (tp->stepping_over_breakpoint && !use_displaced_stepping (gdbarch))
2309 struct regcache *regcache = get_current_regcache ();
2311 set_step_over_info (get_regcache_aspace (regcache),
2312 regcache_read_pc (regcache));
2315 clear_step_over_info ();
2317 insert_breakpoints ();
2319 tp->control.trap_expected = tp->stepping_over_breakpoint;
2321 annotate_starting ();
2323 /* Make sure that output from GDB appears before output from the
2325 gdb_flush (gdb_stdout);
2327 /* Refresh prev_pc value just prior to resuming. This used to be
2328 done in stop_waiting, however, setting prev_pc there did not handle
2329 scenarios such as inferior function calls or returning from
2330 a function via the return command. In those cases, the prev_pc
2331 value was not set properly for subsequent commands. The prev_pc value
2332 is used to initialize the starting line number in the ecs. With an
2333 invalid value, the gdb next command ends up stopping at the position
2334 represented by the next line table entry past our start position.
2335 On platforms that generate one line table entry per line, this
2336 is not a problem. However, on the ia64, the compiler generates
2337 extraneous line table entries that do not increase the line number.
2338 When we issue the gdb next command on the ia64 after an inferior call
2339 or a return command, we often end up a few instructions forward, still
2340 within the original line we started.
2342 An attempt was made to refresh the prev_pc at the same time the
2343 execution_control_state is initialized (for instance, just before
2344 waiting for an inferior event). But this approach did not work
2345 because of platforms that use ptrace, where the pc register cannot
2346 be read unless the inferior is stopped. At that point, we are not
2347 guaranteed the inferior is stopped and so the regcache_read_pc() call
2348 can fail. Setting the prev_pc value here ensures the value is updated
2349 correctly when the inferior is stopped. */
2350 tp->prev_pc = regcache_read_pc (get_current_regcache ());
2352 /* Reset to normal state. */
2353 init_infwait_state ();
2355 /* Resume inferior. */
2356 resume (tp->control.trap_expected || step || bpstat_should_step (),
2357 tp->suspend.stop_signal);
2359 /* Wait for it to stop (if not standalone)
2360 and in any case decode why it stopped, and act accordingly. */
2361 /* Do this only if we are not using the event loop, or if the target
2362 does not support asynchronous execution. */
2363 if (!target_can_async_p ())
2365 wait_for_inferior ();
2371 /* Start remote-debugging of a machine over a serial link. */
2374 start_remote (int from_tty)
2376 struct inferior *inferior;
2378 inferior = current_inferior ();
2379 inferior->control.stop_soon = STOP_QUIETLY_REMOTE;
2381 /* Always go on waiting for the target, regardless of the mode. */
2382 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2383 indicate to wait_for_inferior that a target should timeout if
2384 nothing is returned (instead of just blocking). Because of this,
2385 targets expecting an immediate response need to, internally, set
2386 things up so that the target_wait() is forced to eventually
2388 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2389 differentiate to its caller what the state of the target is after
2390 the initial open has been performed. Here we're assuming that
2391 the target has stopped. It should be possible to eventually have
2392 target_open() return to the caller an indication that the target
2393 is currently running and GDB state should be set to the same as
2394 for an async run. */
2395 wait_for_inferior ();
2397 /* Now that the inferior has stopped, do any bookkeeping like
2398 loading shared libraries. We want to do this before normal_stop,
2399 so that the displayed frame is up to date. */
2400 post_create_inferior (¤t_target, from_tty);
2405 /* Initialize static vars when a new inferior begins. */
2408 init_wait_for_inferior (void)
2410 /* These are meaningless until the first time through wait_for_inferior. */
2412 breakpoint_init_inferior (inf_starting);
2414 clear_proceed_status (0);
2416 target_last_wait_ptid = minus_one_ptid;
2418 previous_inferior_ptid = inferior_ptid;
2419 init_infwait_state ();
2421 /* Discard any skipped inlined frames. */
2422 clear_inline_frame_state (minus_one_ptid);
2424 singlestep_ptid = null_ptid;
2429 /* This enum encodes possible reasons for doing a target_wait, so that
2430 wfi can call target_wait in one place. (Ultimately the call will be
2431 moved out of the infinite loop entirely.) */
2435 infwait_normal_state,
2436 infwait_step_watch_state,
2437 infwait_nonstep_watch_state
2440 /* The PTID we'll do a target_wait on.*/
2443 /* Current inferior wait state. */
2444 static enum infwait_states infwait_state;
2446 /* Data to be passed around while handling an event. This data is
2447 discarded between events. */
2448 struct execution_control_state
2451 /* The thread that got the event, if this was a thread event; NULL
2453 struct thread_info *event_thread;
2455 struct target_waitstatus ws;
2456 int stop_func_filled_in;
2457 CORE_ADDR stop_func_start;
2458 CORE_ADDR stop_func_end;
2459 const char *stop_func_name;
2462 /* We were in infwait_step_watch_state or
2463 infwait_nonstep_watch_state state, and the thread reported an
2465 int stepped_after_stopped_by_watchpoint;
2467 /* True if the event thread hit the single-step breakpoint of
2468 another thread. Thus the event doesn't cause a stop, the thread
2469 needs to be single-stepped past the single-step breakpoint before
2470 we can switch back to the original stepping thread. */
2471 int hit_singlestep_breakpoint;
2474 static void handle_inferior_event (struct execution_control_state *ecs);
2476 static void handle_step_into_function (struct gdbarch *gdbarch,
2477 struct execution_control_state *ecs);
2478 static void handle_step_into_function_backward (struct gdbarch *gdbarch,
2479 struct execution_control_state *ecs);
2480 static void handle_signal_stop (struct execution_control_state *ecs);
2481 static void check_exception_resume (struct execution_control_state *,
2482 struct frame_info *);
2484 static void end_stepping_range (struct execution_control_state *ecs);
2485 static void stop_waiting (struct execution_control_state *ecs);
2486 static void prepare_to_wait (struct execution_control_state *ecs);
2487 static void keep_going (struct execution_control_state *ecs);
2488 static void process_event_stop_test (struct execution_control_state *ecs);
2489 static int switch_back_to_stepped_thread (struct execution_control_state *ecs);
2491 /* Callback for iterate over threads. If the thread is stopped, but
2492 the user/frontend doesn't know about that yet, go through
2493 normal_stop, as if the thread had just stopped now. ARG points at
2494 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2495 ptid_is_pid(PTID) is true, applies to all threads of the process
2496 pointed at by PTID. Otherwise, apply only to the thread pointed by
2500 infrun_thread_stop_requested_callback (struct thread_info *info, void *arg)
2502 ptid_t ptid = * (ptid_t *) arg;
2504 if ((ptid_equal (info->ptid, ptid)
2505 || ptid_equal (minus_one_ptid, ptid)
2506 || (ptid_is_pid (ptid)
2507 && ptid_get_pid (ptid) == ptid_get_pid (info->ptid)))
2508 && is_running (info->ptid)
2509 && !is_executing (info->ptid))
2511 struct cleanup *old_chain;
2512 struct execution_control_state ecss;
2513 struct execution_control_state *ecs = &ecss;
2515 memset (ecs, 0, sizeof (*ecs));
2517 old_chain = make_cleanup_restore_current_thread ();
2519 overlay_cache_invalid = 1;
2520 /* Flush target cache before starting to handle each event.
2521 Target was running and cache could be stale. This is just a
2522 heuristic. Running threads may modify target memory, but we
2523 don't get any event. */
2524 target_dcache_invalidate ();
2526 /* Go through handle_inferior_event/normal_stop, so we always
2527 have consistent output as if the stop event had been
2529 ecs->ptid = info->ptid;
2530 ecs->event_thread = find_thread_ptid (info->ptid);
2531 ecs->ws.kind = TARGET_WAITKIND_STOPPED;
2532 ecs->ws.value.sig = GDB_SIGNAL_0;
2534 handle_inferior_event (ecs);
2536 if (!ecs->wait_some_more)
2538 struct thread_info *tp;
2542 /* Finish off the continuations. */
2543 tp = inferior_thread ();
2544 do_all_intermediate_continuations_thread (tp, 1);
2545 do_all_continuations_thread (tp, 1);
2548 do_cleanups (old_chain);
2554 /* This function is attached as a "thread_stop_requested" observer.
2555 Cleanup local state that assumed the PTID was to be resumed, and
2556 report the stop to the frontend. */
2559 infrun_thread_stop_requested (ptid_t ptid)
2561 struct displaced_step_inferior_state *displaced;
2563 /* PTID was requested to stop. Remove it from the displaced
2564 stepping queue, so we don't try to resume it automatically. */
2566 for (displaced = displaced_step_inferior_states;
2568 displaced = displaced->next)
2570 struct displaced_step_request *it, **prev_next_p;
2572 it = displaced->step_request_queue;
2573 prev_next_p = &displaced->step_request_queue;
2576 if (ptid_match (it->ptid, ptid))
2578 *prev_next_p = it->next;
2584 prev_next_p = &it->next;
2591 iterate_over_threads (infrun_thread_stop_requested_callback, &ptid);
2595 infrun_thread_thread_exit (struct thread_info *tp, int silent)
2597 if (ptid_equal (target_last_wait_ptid, tp->ptid))
2598 nullify_last_target_wait_ptid ();
2601 /* Callback for iterate_over_threads. */
2604 delete_step_resume_breakpoint_callback (struct thread_info *info, void *data)
2606 if (is_exited (info->ptid))
2609 delete_step_resume_breakpoint (info);
2610 delete_exception_resume_breakpoint (info);
2614 /* In all-stop, delete the step resume breakpoint of any thread that
2615 had one. In non-stop, delete the step resume breakpoint of the
2616 thread that just stopped. */
2619 delete_step_thread_step_resume_breakpoint (void)
2621 if (!target_has_execution
2622 || ptid_equal (inferior_ptid, null_ptid))
2623 /* If the inferior has exited, we have already deleted the step
2624 resume breakpoints out of GDB's lists. */
2629 /* If in non-stop mode, only delete the step-resume or
2630 longjmp-resume breakpoint of the thread that just stopped
2632 struct thread_info *tp = inferior_thread ();
2634 delete_step_resume_breakpoint (tp);
2635 delete_exception_resume_breakpoint (tp);
2638 /* In all-stop mode, delete all step-resume and longjmp-resume
2639 breakpoints of any thread that had them. */
2640 iterate_over_threads (delete_step_resume_breakpoint_callback, NULL);
2643 /* A cleanup wrapper. */
2646 delete_step_thread_step_resume_breakpoint_cleanup (void *arg)
2648 delete_step_thread_step_resume_breakpoint ();
2651 /* Pretty print the results of target_wait, for debugging purposes. */
2654 print_target_wait_results (ptid_t waiton_ptid, ptid_t result_ptid,
2655 const struct target_waitstatus *ws)
2657 char *status_string = target_waitstatus_to_string (ws);
2658 struct ui_file *tmp_stream = mem_fileopen ();
2661 /* The text is split over several lines because it was getting too long.
2662 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2663 output as a unit; we want only one timestamp printed if debug_timestamp
2666 fprintf_unfiltered (tmp_stream,
2667 "infrun: target_wait (%d", ptid_get_pid (waiton_ptid));
2668 if (ptid_get_pid (waiton_ptid) != -1)
2669 fprintf_unfiltered (tmp_stream,
2670 " [%s]", target_pid_to_str (waiton_ptid));
2671 fprintf_unfiltered (tmp_stream, ", status) =\n");
2672 fprintf_unfiltered (tmp_stream,
2673 "infrun: %d [%s],\n",
2674 ptid_get_pid (result_ptid),
2675 target_pid_to_str (result_ptid));
2676 fprintf_unfiltered (tmp_stream,
2680 text = ui_file_xstrdup (tmp_stream, NULL);
2682 /* This uses %s in part to handle %'s in the text, but also to avoid
2683 a gcc error: the format attribute requires a string literal. */
2684 fprintf_unfiltered (gdb_stdlog, "%s", text);
2686 xfree (status_string);
2688 ui_file_delete (tmp_stream);
2691 /* Prepare and stabilize the inferior for detaching it. E.g.,
2692 detaching while a thread is displaced stepping is a recipe for
2693 crashing it, as nothing would readjust the PC out of the scratch
2697 prepare_for_detach (void)
2699 struct inferior *inf = current_inferior ();
2700 ptid_t pid_ptid = pid_to_ptid (inf->pid);
2701 struct cleanup *old_chain_1;
2702 struct displaced_step_inferior_state *displaced;
2704 displaced = get_displaced_stepping_state (inf->pid);
2706 /* Is any thread of this process displaced stepping? If not,
2707 there's nothing else to do. */
2708 if (displaced == NULL || ptid_equal (displaced->step_ptid, null_ptid))
2712 fprintf_unfiltered (gdb_stdlog,
2713 "displaced-stepping in-process while detaching");
2715 old_chain_1 = make_cleanup_restore_integer (&inf->detaching);
2718 while (!ptid_equal (displaced->step_ptid, null_ptid))
2720 struct cleanup *old_chain_2;
2721 struct execution_control_state ecss;
2722 struct execution_control_state *ecs;
2725 memset (ecs, 0, sizeof (*ecs));
2727 overlay_cache_invalid = 1;
2728 /* Flush target cache before starting to handle each event.
2729 Target was running and cache could be stale. This is just a
2730 heuristic. Running threads may modify target memory, but we
2731 don't get any event. */
2732 target_dcache_invalidate ();
2734 if (deprecated_target_wait_hook)
2735 ecs->ptid = deprecated_target_wait_hook (pid_ptid, &ecs->ws, 0);
2737 ecs->ptid = target_wait (pid_ptid, &ecs->ws, 0);
2740 print_target_wait_results (pid_ptid, ecs->ptid, &ecs->ws);
2742 /* If an error happens while handling the event, propagate GDB's
2743 knowledge of the executing state to the frontend/user running
2745 old_chain_2 = make_cleanup (finish_thread_state_cleanup,
2748 /* Now figure out what to do with the result of the result. */
2749 handle_inferior_event (ecs);
2751 /* No error, don't finish the state yet. */
2752 discard_cleanups (old_chain_2);
2754 /* Breakpoints and watchpoints are not installed on the target
2755 at this point, and signals are passed directly to the
2756 inferior, so this must mean the process is gone. */
2757 if (!ecs->wait_some_more)
2759 discard_cleanups (old_chain_1);
2760 error (_("Program exited while detaching"));
2764 discard_cleanups (old_chain_1);
2767 /* Wait for control to return from inferior to debugger.
2769 If inferior gets a signal, we may decide to start it up again
2770 instead of returning. That is why there is a loop in this function.
2771 When this function actually returns it means the inferior
2772 should be left stopped and GDB should read more commands. */
2775 wait_for_inferior (void)
2777 struct cleanup *old_cleanups;
2781 (gdb_stdlog, "infrun: wait_for_inferior ()\n");
2784 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup, NULL);
2788 struct execution_control_state ecss;
2789 struct execution_control_state *ecs = &ecss;
2790 struct cleanup *old_chain;
2792 memset (ecs, 0, sizeof (*ecs));
2794 overlay_cache_invalid = 1;
2796 /* Flush target cache before starting to handle each event.
2797 Target was running and cache could be stale. This is just a
2798 heuristic. Running threads may modify target memory, but we
2799 don't get any event. */
2800 target_dcache_invalidate ();
2802 if (deprecated_target_wait_hook)
2803 ecs->ptid = deprecated_target_wait_hook (waiton_ptid, &ecs->ws, 0);
2805 ecs->ptid = target_wait (waiton_ptid, &ecs->ws, 0);
2808 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
2810 /* If an error happens while handling the event, propagate GDB's
2811 knowledge of the executing state to the frontend/user running
2813 old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
2815 /* Now figure out what to do with the result of the result. */
2816 handle_inferior_event (ecs);
2818 /* No error, don't finish the state yet. */
2819 discard_cleanups (old_chain);
2821 if (!ecs->wait_some_more)
2825 do_cleanups (old_cleanups);
2828 /* Asynchronous version of wait_for_inferior. It is called by the
2829 event loop whenever a change of state is detected on the file
2830 descriptor corresponding to the target. It can be called more than
2831 once to complete a single execution command. In such cases we need
2832 to keep the state in a global variable ECSS. If it is the last time
2833 that this function is called for a single execution command, then
2834 report to the user that the inferior has stopped, and do the
2835 necessary cleanups. */
2838 fetch_inferior_event (void *client_data)
2840 struct execution_control_state ecss;
2841 struct execution_control_state *ecs = &ecss;
2842 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
2843 struct cleanup *ts_old_chain;
2844 int was_sync = sync_execution;
2847 memset (ecs, 0, sizeof (*ecs));
2849 /* We're handling a live event, so make sure we're doing live
2850 debugging. If we're looking at traceframes while the target is
2851 running, we're going to need to get back to that mode after
2852 handling the event. */
2855 make_cleanup_restore_current_traceframe ();
2856 set_current_traceframe (-1);
2860 /* In non-stop mode, the user/frontend should not notice a thread
2861 switch due to internal events. Make sure we reverse to the
2862 user selected thread and frame after handling the event and
2863 running any breakpoint commands. */
2864 make_cleanup_restore_current_thread ();
2866 overlay_cache_invalid = 1;
2867 /* Flush target cache before starting to handle each event. Target
2868 was running and cache could be stale. This is just a heuristic.
2869 Running threads may modify target memory, but we don't get any
2871 target_dcache_invalidate ();
2873 make_cleanup_restore_integer (&execution_direction);
2874 execution_direction = target_execution_direction ();
2876 if (deprecated_target_wait_hook)
2878 deprecated_target_wait_hook (waiton_ptid, &ecs->ws, TARGET_WNOHANG);
2880 ecs->ptid = target_wait (waiton_ptid, &ecs->ws, TARGET_WNOHANG);
2883 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
2885 /* If an error happens while handling the event, propagate GDB's
2886 knowledge of the executing state to the frontend/user running
2889 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
2891 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &ecs->ptid);
2893 /* Get executed before make_cleanup_restore_current_thread above to apply
2894 still for the thread which has thrown the exception. */
2895 make_bpstat_clear_actions_cleanup ();
2897 /* Now figure out what to do with the result of the result. */
2898 handle_inferior_event (ecs);
2900 if (!ecs->wait_some_more)
2902 struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
2904 delete_step_thread_step_resume_breakpoint ();
2906 /* We may not find an inferior if this was a process exit. */
2907 if (inf == NULL || inf->control.stop_soon == NO_STOP_QUIETLY)
2910 if (target_has_execution
2911 && ecs->ws.kind != TARGET_WAITKIND_NO_RESUMED
2912 && ecs->ws.kind != TARGET_WAITKIND_EXITED
2913 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
2914 && ecs->event_thread->step_multi
2915 && ecs->event_thread->control.stop_step)
2916 inferior_event_handler (INF_EXEC_CONTINUE, NULL);
2919 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
2924 /* No error, don't finish the thread states yet. */
2925 discard_cleanups (ts_old_chain);
2927 /* Revert thread and frame. */
2928 do_cleanups (old_chain);
2930 /* If the inferior was in sync execution mode, and now isn't,
2931 restore the prompt (a synchronous execution command has finished,
2932 and we're ready for input). */
2933 if (interpreter_async && was_sync && !sync_execution)
2934 observer_notify_sync_execution_done ();
2938 && exec_done_display_p
2939 && (ptid_equal (inferior_ptid, null_ptid)
2940 || !is_running (inferior_ptid)))
2941 printf_unfiltered (_("completed.\n"));
2944 /* Record the frame and location we're currently stepping through. */
2946 set_step_info (struct frame_info *frame, struct symtab_and_line sal)
2948 struct thread_info *tp = inferior_thread ();
2950 tp->control.step_frame_id = get_frame_id (frame);
2951 tp->control.step_stack_frame_id = get_stack_frame_id (frame);
2953 tp->current_symtab = sal.symtab;
2954 tp->current_line = sal.line;
2957 /* Clear context switchable stepping state. */
2960 init_thread_stepping_state (struct thread_info *tss)
2962 tss->stepping_over_breakpoint = 0;
2963 tss->step_after_step_resume_breakpoint = 0;
2966 /* Set the cached copy of the last ptid/waitstatus. */
2969 set_last_target_status (ptid_t ptid, struct target_waitstatus status)
2971 target_last_wait_ptid = ptid;
2972 target_last_waitstatus = status;
2975 /* Return the cached copy of the last pid/waitstatus returned by
2976 target_wait()/deprecated_target_wait_hook(). The data is actually
2977 cached by handle_inferior_event(), which gets called immediately
2978 after target_wait()/deprecated_target_wait_hook(). */
2981 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
2983 *ptidp = target_last_wait_ptid;
2984 *status = target_last_waitstatus;
2988 nullify_last_target_wait_ptid (void)
2990 target_last_wait_ptid = minus_one_ptid;
2993 /* Switch thread contexts. */
2996 context_switch (ptid_t ptid)
2998 if (debug_infrun && !ptid_equal (ptid, inferior_ptid))
3000 fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ",
3001 target_pid_to_str (inferior_ptid));
3002 fprintf_unfiltered (gdb_stdlog, "to %s\n",
3003 target_pid_to_str (ptid));
3006 switch_to_thread (ptid);
3010 adjust_pc_after_break (struct execution_control_state *ecs)
3012 struct regcache *regcache;
3013 struct gdbarch *gdbarch;
3014 struct address_space *aspace;
3015 CORE_ADDR breakpoint_pc, decr_pc;
3017 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
3018 we aren't, just return.
3020 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
3021 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
3022 implemented by software breakpoints should be handled through the normal
3025 NOTE drow/2004-01-31: On some targets, breakpoints may generate
3026 different signals (SIGILL or SIGEMT for instance), but it is less
3027 clear where the PC is pointing afterwards. It may not match
3028 gdbarch_decr_pc_after_break. I don't know any specific target that
3029 generates these signals at breakpoints (the code has been in GDB since at
3030 least 1992) so I can not guess how to handle them here.
3032 In earlier versions of GDB, a target with
3033 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
3034 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
3035 target with both of these set in GDB history, and it seems unlikely to be
3036 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
3038 if (ecs->ws.kind != TARGET_WAITKIND_STOPPED)
3041 if (ecs->ws.value.sig != GDB_SIGNAL_TRAP)
3044 /* In reverse execution, when a breakpoint is hit, the instruction
3045 under it has already been de-executed. The reported PC always
3046 points at the breakpoint address, so adjusting it further would
3047 be wrong. E.g., consider this case on a decr_pc_after_break == 1
3050 B1 0x08000000 : INSN1
3051 B2 0x08000001 : INSN2
3053 PC -> 0x08000003 : INSN4
3055 Say you're stopped at 0x08000003 as above. Reverse continuing
3056 from that point should hit B2 as below. Reading the PC when the
3057 SIGTRAP is reported should read 0x08000001 and INSN2 should have
3058 been de-executed already.
3060 B1 0x08000000 : INSN1
3061 B2 PC -> 0x08000001 : INSN2
3065 We can't apply the same logic as for forward execution, because
3066 we would wrongly adjust the PC to 0x08000000, since there's a
3067 breakpoint at PC - 1. We'd then report a hit on B1, although
3068 INSN1 hadn't been de-executed yet. Doing nothing is the correct
3070 if (execution_direction == EXEC_REVERSE)
3073 /* If this target does not decrement the PC after breakpoints, then
3074 we have nothing to do. */
3075 regcache = get_thread_regcache (ecs->ptid);
3076 gdbarch = get_regcache_arch (regcache);
3078 decr_pc = target_decr_pc_after_break (gdbarch);
3082 aspace = get_regcache_aspace (regcache);
3084 /* Find the location where (if we've hit a breakpoint) the
3085 breakpoint would be. */
3086 breakpoint_pc = regcache_read_pc (regcache) - decr_pc;
3088 /* Check whether there actually is a software breakpoint inserted at
3091 If in non-stop mode, a race condition is possible where we've
3092 removed a breakpoint, but stop events for that breakpoint were
3093 already queued and arrive later. To suppress those spurious
3094 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3095 and retire them after a number of stop events are reported. */
3096 if (software_breakpoint_inserted_here_p (aspace, breakpoint_pc)
3097 || (non_stop && moribund_breakpoint_here_p (aspace, breakpoint_pc)))
3099 struct cleanup *old_cleanups = make_cleanup (null_cleanup, NULL);
3101 if (record_full_is_used ())
3102 record_full_gdb_operation_disable_set ();
3104 /* When using hardware single-step, a SIGTRAP is reported for both
3105 a completed single-step and a software breakpoint. Need to
3106 differentiate between the two, as the latter needs adjusting
3107 but the former does not.
3109 The SIGTRAP can be due to a completed hardware single-step only if
3110 - we didn't insert software single-step breakpoints
3111 - the thread to be examined is still the current thread
3112 - this thread is currently being stepped
3114 If any of these events did not occur, we must have stopped due
3115 to hitting a software breakpoint, and have to back up to the
3118 As a special case, we could have hardware single-stepped a
3119 software breakpoint. In this case (prev_pc == breakpoint_pc),
3120 we also need to back up to the breakpoint address. */
3122 if (singlestep_breakpoints_inserted_p
3123 || !ptid_equal (ecs->ptid, inferior_ptid)
3124 || !currently_stepping (ecs->event_thread)
3125 || ecs->event_thread->prev_pc == breakpoint_pc)
3126 regcache_write_pc (regcache, breakpoint_pc);
3128 do_cleanups (old_cleanups);
3133 init_infwait_state (void)
3135 waiton_ptid = pid_to_ptid (-1);
3136 infwait_state = infwait_normal_state;
3140 stepped_in_from (struct frame_info *frame, struct frame_id step_frame_id)
3142 for (frame = get_prev_frame (frame);
3144 frame = get_prev_frame (frame))
3146 if (frame_id_eq (get_frame_id (frame), step_frame_id))
3148 if (get_frame_type (frame) != INLINE_FRAME)
3155 /* Auxiliary function that handles syscall entry/return events.
3156 It returns 1 if the inferior should keep going (and GDB
3157 should ignore the event), or 0 if the event deserves to be
3161 handle_syscall_event (struct execution_control_state *ecs)
3163 struct regcache *regcache;
3166 if (!ptid_equal (ecs->ptid, inferior_ptid))
3167 context_switch (ecs->ptid);
3169 regcache = get_thread_regcache (ecs->ptid);
3170 syscall_number = ecs->ws.value.syscall_number;
3171 stop_pc = regcache_read_pc (regcache);
3173 if (catch_syscall_enabled () > 0
3174 && catching_syscall_number (syscall_number) > 0)
3177 fprintf_unfiltered (gdb_stdlog, "infrun: syscall number = '%d'\n",
3180 ecs->event_thread->control.stop_bpstat
3181 = bpstat_stop_status (get_regcache_aspace (regcache),
3182 stop_pc, ecs->ptid, &ecs->ws);
3184 if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
3186 /* Catchpoint hit. */
3191 /* If no catchpoint triggered for this, then keep going. */
3196 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3199 fill_in_stop_func (struct gdbarch *gdbarch,
3200 struct execution_control_state *ecs)
3202 if (!ecs->stop_func_filled_in)
3204 /* Don't care about return value; stop_func_start and stop_func_name
3205 will both be 0 if it doesn't work. */
3206 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
3207 &ecs->stop_func_start, &ecs->stop_func_end);
3208 ecs->stop_func_start
3209 += gdbarch_deprecated_function_start_offset (gdbarch);
3211 if (gdbarch_skip_entrypoint_p (gdbarch))
3212 ecs->stop_func_start = gdbarch_skip_entrypoint (gdbarch,
3213 ecs->stop_func_start);
3215 ecs->stop_func_filled_in = 1;
3220 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
3222 static enum stop_kind
3223 get_inferior_stop_soon (ptid_t ptid)
3225 struct inferior *inf = find_inferior_pid (ptid_get_pid (ptid));
3227 gdb_assert (inf != NULL);
3228 return inf->control.stop_soon;
3231 /* Given an execution control state that has been freshly filled in by
3232 an event from the inferior, figure out what it means and take
3235 The alternatives are:
3237 1) stop_waiting and return; to really stop and return to the
3240 2) keep_going and return; to wait for the next event (set
3241 ecs->event_thread->stepping_over_breakpoint to 1 to single step
3245 handle_inferior_event (struct execution_control_state *ecs)
3247 enum stop_kind stop_soon;
3249 if (ecs->ws.kind == TARGET_WAITKIND_IGNORE)
3251 /* We had an event in the inferior, but we are not interested in
3252 handling it at this level. The lower layers have already
3253 done what needs to be done, if anything.
3255 One of the possible circumstances for this is when the
3256 inferior produces output for the console. The inferior has
3257 not stopped, and we are ignoring the event. Another possible
3258 circumstance is any event which the lower level knows will be
3259 reported multiple times without an intervening resume. */
3261 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n");
3262 prepare_to_wait (ecs);
3266 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED
3267 && target_can_async_p () && !sync_execution)
3269 /* There were no unwaited-for children left in the target, but,
3270 we're not synchronously waiting for events either. Just
3271 ignore. Otherwise, if we were running a synchronous
3272 execution command, we need to cancel it and give the user
3273 back the terminal. */
3275 fprintf_unfiltered (gdb_stdlog,
3276 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3277 prepare_to_wait (ecs);
3281 /* Cache the last pid/waitstatus. */
3282 set_last_target_status (ecs->ptid, ecs->ws);
3284 /* Always clear state belonging to the previous time we stopped. */
3285 stop_stack_dummy = STOP_NONE;
3287 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED)
3289 /* No unwaited-for children left. IOW, all resumed children
3292 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3294 stop_print_frame = 0;
3299 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
3300 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
3302 ecs->event_thread = find_thread_ptid (ecs->ptid);
3303 /* If it's a new thread, add it to the thread database. */
3304 if (ecs->event_thread == NULL)
3305 ecs->event_thread = add_thread (ecs->ptid);
3307 /* Disable range stepping. If the next step request could use a
3308 range, this will be end up re-enabled then. */
3309 ecs->event_thread->control.may_range_step = 0;
3312 /* Dependent on valid ECS->EVENT_THREAD. */
3313 adjust_pc_after_break (ecs);
3315 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3316 reinit_frame_cache ();
3318 breakpoint_retire_moribund ();
3320 /* First, distinguish signals caused by the debugger from signals
3321 that have to do with the program's own actions. Note that
3322 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3323 on the operating system version. Here we detect when a SIGILL or
3324 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3325 something similar for SIGSEGV, since a SIGSEGV will be generated
3326 when we're trying to execute a breakpoint instruction on a
3327 non-executable stack. This happens for call dummy breakpoints
3328 for architectures like SPARC that place call dummies on the
3330 if (ecs->ws.kind == TARGET_WAITKIND_STOPPED
3331 && (ecs->ws.value.sig == GDB_SIGNAL_ILL
3332 || ecs->ws.value.sig == GDB_SIGNAL_SEGV
3333 || ecs->ws.value.sig == GDB_SIGNAL_EMT))
3335 struct regcache *regcache = get_thread_regcache (ecs->ptid);
3337 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache),
3338 regcache_read_pc (regcache)))
3341 fprintf_unfiltered (gdb_stdlog,
3342 "infrun: Treating signal as SIGTRAP\n");
3343 ecs->ws.value.sig = GDB_SIGNAL_TRAP;
3347 /* Mark the non-executing threads accordingly. In all-stop, all
3348 threads of all processes are stopped when we get any event
3349 reported. In non-stop mode, only the event thread stops. If
3350 we're handling a process exit in non-stop mode, there's nothing
3351 to do, as threads of the dead process are gone, and threads of
3352 any other process were left running. */
3354 set_executing (minus_one_ptid, 0);
3355 else if (ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
3356 && ecs->ws.kind != TARGET_WAITKIND_EXITED)
3357 set_executing (ecs->ptid, 0);
3359 switch (infwait_state)
3361 case infwait_normal_state:
3363 fprintf_unfiltered (gdb_stdlog, "infrun: infwait_normal_state\n");
3366 case infwait_step_watch_state:
3368 fprintf_unfiltered (gdb_stdlog,
3369 "infrun: infwait_step_watch_state\n");
3371 ecs->stepped_after_stopped_by_watchpoint = 1;
3374 case infwait_nonstep_watch_state:
3376 fprintf_unfiltered (gdb_stdlog,
3377 "infrun: infwait_nonstep_watch_state\n");
3378 insert_breakpoints ();
3380 /* FIXME-maybe: is this cleaner than setting a flag? Does it
3381 handle things like signals arriving and other things happening
3382 in combination correctly? */
3383 ecs->stepped_after_stopped_by_watchpoint = 1;
3387 internal_error (__FILE__, __LINE__, _("bad switch"));
3390 infwait_state = infwait_normal_state;
3391 waiton_ptid = pid_to_ptid (-1);
3393 switch (ecs->ws.kind)
3395 case TARGET_WAITKIND_LOADED:
3397 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n");
3398 if (!ptid_equal (ecs->ptid, inferior_ptid))
3399 context_switch (ecs->ptid);
3400 /* Ignore gracefully during startup of the inferior, as it might
3401 be the shell which has just loaded some objects, otherwise
3402 add the symbols for the newly loaded objects. Also ignore at
3403 the beginning of an attach or remote session; we will query
3404 the full list of libraries once the connection is
3407 stop_soon = get_inferior_stop_soon (ecs->ptid);
3408 if (stop_soon == NO_STOP_QUIETLY)
3410 struct regcache *regcache;
3412 regcache = get_thread_regcache (ecs->ptid);
3414 handle_solib_event ();
3416 ecs->event_thread->control.stop_bpstat
3417 = bpstat_stop_status (get_regcache_aspace (regcache),
3418 stop_pc, ecs->ptid, &ecs->ws);
3420 if (bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
3422 /* A catchpoint triggered. */
3423 process_event_stop_test (ecs);
3427 /* If requested, stop when the dynamic linker notifies
3428 gdb of events. This allows the user to get control
3429 and place breakpoints in initializer routines for
3430 dynamically loaded objects (among other things). */
3431 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
3432 if (stop_on_solib_events)
3434 /* Make sure we print "Stopped due to solib-event" in
3436 stop_print_frame = 1;
3443 /* If we are skipping through a shell, or through shared library
3444 loading that we aren't interested in, resume the program. If
3445 we're running the program normally, also resume. */
3446 if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY)
3448 /* Loading of shared libraries might have changed breakpoint
3449 addresses. Make sure new breakpoints are inserted. */
3450 if (stop_soon == NO_STOP_QUIETLY)
3451 insert_breakpoints ();
3452 resume (0, GDB_SIGNAL_0);
3453 prepare_to_wait (ecs);
3457 /* But stop if we're attaching or setting up a remote
3459 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
3460 || stop_soon == STOP_QUIETLY_REMOTE)
3463 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
3468 internal_error (__FILE__, __LINE__,
3469 _("unhandled stop_soon: %d"), (int) stop_soon);
3471 case TARGET_WAITKIND_SPURIOUS:
3473 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3474 if (!ptid_equal (ecs->ptid, inferior_ptid))
3475 context_switch (ecs->ptid);
3476 resume (0, GDB_SIGNAL_0);
3477 prepare_to_wait (ecs);
3480 case TARGET_WAITKIND_EXITED:
3481 case TARGET_WAITKIND_SIGNALLED:
3484 if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
3485 fprintf_unfiltered (gdb_stdlog,
3486 "infrun: TARGET_WAITKIND_EXITED\n");
3488 fprintf_unfiltered (gdb_stdlog,
3489 "infrun: TARGET_WAITKIND_SIGNALLED\n");
3492 inferior_ptid = ecs->ptid;
3493 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs->ptid)));
3494 set_current_program_space (current_inferior ()->pspace);
3495 handle_vfork_child_exec_or_exit (0);
3496 target_terminal_ours (); /* Must do this before mourn anyway. */
3498 /* Clearing any previous state of convenience variables. */
3499 clear_exit_convenience_vars ();
3501 if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
3503 /* Record the exit code in the convenience variable $_exitcode, so
3504 that the user can inspect this again later. */
3505 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3506 (LONGEST) ecs->ws.value.integer);
3508 /* Also record this in the inferior itself. */
3509 current_inferior ()->has_exit_code = 1;
3510 current_inferior ()->exit_code = (LONGEST) ecs->ws.value.integer;
3512 /* Support the --return-child-result option. */
3513 return_child_result_value = ecs->ws.value.integer;
3515 observer_notify_exited (ecs->ws.value.integer);
3519 struct regcache *regcache = get_thread_regcache (ecs->ptid);
3520 struct gdbarch *gdbarch = get_regcache_arch (regcache);
3522 if (gdbarch_gdb_signal_to_target_p (gdbarch))
3524 /* Set the value of the internal variable $_exitsignal,
3525 which holds the signal uncaught by the inferior. */
3526 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
3527 gdbarch_gdb_signal_to_target (gdbarch,
3528 ecs->ws.value.sig));
3532 /* We don't have access to the target's method used for
3533 converting between signal numbers (GDB's internal
3534 representation <-> target's representation).
3535 Therefore, we cannot do a good job at displaying this
3536 information to the user. It's better to just warn
3537 her about it (if infrun debugging is enabled), and
3540 fprintf_filtered (gdb_stdlog, _("\
3541 Cannot fill $_exitsignal with the correct signal number.\n"));
3544 observer_notify_signal_exited (ecs->ws.value.sig);
3547 gdb_flush (gdb_stdout);
3548 target_mourn_inferior ();
3549 singlestep_breakpoints_inserted_p = 0;
3550 cancel_single_step_breakpoints ();
3551 stop_print_frame = 0;
3555 /* The following are the only cases in which we keep going;
3556 the above cases end in a continue or goto. */
3557 case TARGET_WAITKIND_FORKED:
3558 case TARGET_WAITKIND_VFORKED:
3561 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
3562 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
3564 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_VFORKED\n");
3567 /* Check whether the inferior is displaced stepping. */
3569 struct regcache *regcache = get_thread_regcache (ecs->ptid);
3570 struct gdbarch *gdbarch = get_regcache_arch (regcache);
3571 struct displaced_step_inferior_state *displaced
3572 = get_displaced_stepping_state (ptid_get_pid (ecs->ptid));
3574 /* If checking displaced stepping is supported, and thread
3575 ecs->ptid is displaced stepping. */
3576 if (displaced && ptid_equal (displaced->step_ptid, ecs->ptid))
3578 struct inferior *parent_inf
3579 = find_inferior_pid (ptid_get_pid (ecs->ptid));
3580 struct regcache *child_regcache;
3581 CORE_ADDR parent_pc;
3583 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3584 indicating that the displaced stepping of syscall instruction
3585 has been done. Perform cleanup for parent process here. Note
3586 that this operation also cleans up the child process for vfork,
3587 because their pages are shared. */
3588 displaced_step_fixup (ecs->ptid, GDB_SIGNAL_TRAP);
3590 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
3592 /* Restore scratch pad for child process. */
3593 displaced_step_restore (displaced, ecs->ws.value.related_pid);
3596 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3597 the child's PC is also within the scratchpad. Set the child's PC
3598 to the parent's PC value, which has already been fixed up.
3599 FIXME: we use the parent's aspace here, although we're touching
3600 the child, because the child hasn't been added to the inferior
3601 list yet at this point. */
3604 = get_thread_arch_aspace_regcache (ecs->ws.value.related_pid,
3606 parent_inf->aspace);
3607 /* Read PC value of parent process. */
3608 parent_pc = regcache_read_pc (regcache);
3610 if (debug_displaced)
3611 fprintf_unfiltered (gdb_stdlog,
3612 "displaced: write child pc from %s to %s\n",
3614 regcache_read_pc (child_regcache)),
3615 paddress (gdbarch, parent_pc));
3617 regcache_write_pc (child_regcache, parent_pc);
3621 if (!ptid_equal (ecs->ptid, inferior_ptid))
3622 context_switch (ecs->ptid);
3624 /* Immediately detach breakpoints from the child before there's
3625 any chance of letting the user delete breakpoints from the
3626 breakpoint lists. If we don't do this early, it's easy to
3627 leave left over traps in the child, vis: "break foo; catch
3628 fork; c; <fork>; del; c; <child calls foo>". We only follow
3629 the fork on the last `continue', and by that time the
3630 breakpoint at "foo" is long gone from the breakpoint table.
3631 If we vforked, then we don't need to unpatch here, since both
3632 parent and child are sharing the same memory pages; we'll
3633 need to unpatch at follow/detach time instead to be certain
3634 that new breakpoints added between catchpoint hit time and
3635 vfork follow are detached. */
3636 if (ecs->ws.kind != TARGET_WAITKIND_VFORKED)
3638 /* This won't actually modify the breakpoint list, but will
3639 physically remove the breakpoints from the child. */
3640 detach_breakpoints (ecs->ws.value.related_pid);
3643 if (singlestep_breakpoints_inserted_p)
3645 /* Pull the single step breakpoints out of the target. */
3646 remove_single_step_breakpoints ();
3647 singlestep_breakpoints_inserted_p = 0;
3650 /* In case the event is caught by a catchpoint, remember that
3651 the event is to be followed at the next resume of the thread,
3652 and not immediately. */
3653 ecs->event_thread->pending_follow = ecs->ws;
3655 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3657 ecs->event_thread->control.stop_bpstat
3658 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3659 stop_pc, ecs->ptid, &ecs->ws);
3661 /* If no catchpoint triggered for this, then keep going. Note
3662 that we're interested in knowing the bpstat actually causes a
3663 stop, not just if it may explain the signal. Software
3664 watchpoints, for example, always appear in the bpstat. */
3665 if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
3671 = (follow_fork_mode_string == follow_fork_mode_child);
3673 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
3675 should_resume = follow_fork ();
3678 child = ecs->ws.value.related_pid;
3680 /* In non-stop mode, also resume the other branch. */
3681 if (non_stop && !detach_fork)
3684 switch_to_thread (parent);
3686 switch_to_thread (child);
3688 ecs->event_thread = inferior_thread ();
3689 ecs->ptid = inferior_ptid;
3694 switch_to_thread (child);
3696 switch_to_thread (parent);
3698 ecs->event_thread = inferior_thread ();
3699 ecs->ptid = inferior_ptid;
3707 process_event_stop_test (ecs);
3710 case TARGET_WAITKIND_VFORK_DONE:
3711 /* Done with the shared memory region. Re-insert breakpoints in
3712 the parent, and keep going. */
3715 fprintf_unfiltered (gdb_stdlog,
3716 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3718 if (!ptid_equal (ecs->ptid, inferior_ptid))
3719 context_switch (ecs->ptid);
3721 current_inferior ()->waiting_for_vfork_done = 0;
3722 current_inferior ()->pspace->breakpoints_not_allowed = 0;
3723 /* This also takes care of reinserting breakpoints in the
3724 previously locked inferior. */
3728 case TARGET_WAITKIND_EXECD:
3730 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n");
3732 if (!ptid_equal (ecs->ptid, inferior_ptid))
3733 context_switch (ecs->ptid);
3735 singlestep_breakpoints_inserted_p = 0;
3736 cancel_single_step_breakpoints ();
3738 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3740 /* Do whatever is necessary to the parent branch of the vfork. */
3741 handle_vfork_child_exec_or_exit (1);
3743 /* This causes the eventpoints and symbol table to be reset.
3744 Must do this now, before trying to determine whether to
3746 follow_exec (inferior_ptid, ecs->ws.value.execd_pathname);
3748 ecs->event_thread->control.stop_bpstat
3749 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3750 stop_pc, ecs->ptid, &ecs->ws);
3752 /* Note that this may be referenced from inside
3753 bpstat_stop_status above, through inferior_has_execd. */
3754 xfree (ecs->ws.value.execd_pathname);
3755 ecs->ws.value.execd_pathname = NULL;
3757 /* If no catchpoint triggered for this, then keep going. */
3758 if (!bpstat_causes_stop (ecs->event_thread->control.stop_bpstat))
3760 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
3764 process_event_stop_test (ecs);
3767 /* Be careful not to try to gather much state about a thread
3768 that's in a syscall. It's frequently a losing proposition. */
3769 case TARGET_WAITKIND_SYSCALL_ENTRY:
3771 fprintf_unfiltered (gdb_stdlog,
3772 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3773 /* Getting the current syscall number. */
3774 if (handle_syscall_event (ecs) == 0)
3775 process_event_stop_test (ecs);
3778 /* Before examining the threads further, step this thread to
3779 get it entirely out of the syscall. (We get notice of the
3780 event when the thread is just on the verge of exiting a
3781 syscall. Stepping one instruction seems to get it back
3783 case TARGET_WAITKIND_SYSCALL_RETURN:
3785 fprintf_unfiltered (gdb_stdlog,
3786 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3787 if (handle_syscall_event (ecs) == 0)
3788 process_event_stop_test (ecs);
3791 case TARGET_WAITKIND_STOPPED:
3793 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n");
3794 ecs->event_thread->suspend.stop_signal = ecs->ws.value.sig;
3795 handle_signal_stop (ecs);
3798 case TARGET_WAITKIND_NO_HISTORY:
3800 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
3801 /* Reverse execution: target ran out of history info. */
3803 /* Pull the single step breakpoints out of the target. */
3804 if (singlestep_breakpoints_inserted_p)
3806 if (!ptid_equal (ecs->ptid, inferior_ptid))
3807 context_switch (ecs->ptid);
3808 remove_single_step_breakpoints ();
3809 singlestep_breakpoints_inserted_p = 0;
3811 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3812 observer_notify_no_history ();
3818 /* Come here when the program has stopped with a signal. */
3821 handle_signal_stop (struct execution_control_state *ecs)
3823 struct frame_info *frame;
3824 struct gdbarch *gdbarch;
3825 int stopped_by_watchpoint;
3826 enum stop_kind stop_soon;
3829 gdb_assert (ecs->ws.kind == TARGET_WAITKIND_STOPPED);
3831 /* Do we need to clean up the state of a thread that has
3832 completed a displaced single-step? (Doing so usually affects
3833 the PC, so do it here, before we set stop_pc.) */
3834 displaced_step_fixup (ecs->ptid,
3835 ecs->event_thread->suspend.stop_signal);
3837 /* If we either finished a single-step or hit a breakpoint, but
3838 the user wanted this thread to be stopped, pretend we got a
3839 SIG0 (generic unsignaled stop). */
3840 if (ecs->event_thread->stop_requested
3841 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
3842 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
3844 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3848 struct regcache *regcache = get_thread_regcache (ecs->ptid);
3849 struct gdbarch *gdbarch = get_regcache_arch (regcache);
3850 struct cleanup *old_chain = save_inferior_ptid ();
3852 inferior_ptid = ecs->ptid;
3854 fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = %s\n",
3855 paddress (gdbarch, stop_pc));
3856 if (target_stopped_by_watchpoint ())
3860 fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n");
3862 if (target_stopped_data_address (¤t_target, &addr))
3863 fprintf_unfiltered (gdb_stdlog,
3864 "infrun: stopped data address = %s\n",
3865 paddress (gdbarch, addr));
3867 fprintf_unfiltered (gdb_stdlog,
3868 "infrun: (no data address available)\n");
3871 do_cleanups (old_chain);
3874 /* This is originated from start_remote(), start_inferior() and
3875 shared libraries hook functions. */
3876 stop_soon = get_inferior_stop_soon (ecs->ptid);
3877 if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE)
3879 if (!ptid_equal (ecs->ptid, inferior_ptid))
3880 context_switch (ecs->ptid);
3882 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
3883 stop_print_frame = 1;
3888 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
3891 if (!ptid_equal (ecs->ptid, inferior_ptid))
3892 context_switch (ecs->ptid);
3894 fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n");
3895 stop_print_frame = 0;
3900 /* This originates from attach_command(). We need to overwrite
3901 the stop_signal here, because some kernels don't ignore a
3902 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
3903 See more comments in inferior.h. On the other hand, if we
3904 get a non-SIGSTOP, report it to the user - assume the backend
3905 will handle the SIGSTOP if it should show up later.
3907 Also consider that the attach is complete when we see a
3908 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
3909 target extended-remote report it instead of a SIGSTOP
3910 (e.g. gdbserver). We already rely on SIGTRAP being our
3911 signal, so this is no exception.
3913 Also consider that the attach is complete when we see a
3914 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
3915 the target to stop all threads of the inferior, in case the
3916 low level attach operation doesn't stop them implicitly. If
3917 they weren't stopped implicitly, then the stub will report a
3918 GDB_SIGNAL_0, meaning: stopped for no particular reason
3919 other than GDB's request. */
3920 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
3921 && (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_STOP
3922 || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
3923 || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_0))
3925 stop_print_frame = 1;
3927 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
3931 /* See if something interesting happened to the non-current thread. If
3932 so, then switch to that thread. */
3933 if (!ptid_equal (ecs->ptid, inferior_ptid))
3936 fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n");
3938 context_switch (ecs->ptid);
3940 if (deprecated_context_hook)
3941 deprecated_context_hook (pid_to_thread_id (ecs->ptid));
3944 /* At this point, get hold of the now-current thread's frame. */
3945 frame = get_current_frame ();
3946 gdbarch = get_frame_arch (frame);
3948 /* Pull the single step breakpoints out of the target. */
3949 if (singlestep_breakpoints_inserted_p)
3951 /* However, before doing so, if this single-step breakpoint was
3952 actually for another thread, set this thread up for moving
3954 if (!ptid_equal (ecs->ptid, singlestep_ptid)
3955 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
3957 struct regcache *regcache;
3958 struct address_space *aspace;
3961 regcache = get_thread_regcache (ecs->ptid);
3962 aspace = get_regcache_aspace (regcache);
3963 pc = regcache_read_pc (regcache);
3964 if (single_step_breakpoint_inserted_here_p (aspace, pc))
3968 fprintf_unfiltered (gdb_stdlog,
3969 "infrun: [%s] hit step over single-step"
3970 " breakpoint of [%s]\n",
3971 target_pid_to_str (ecs->ptid),
3972 target_pid_to_str (singlestep_ptid));
3974 ecs->hit_singlestep_breakpoint = 1;
3978 remove_single_step_breakpoints ();
3979 singlestep_breakpoints_inserted_p = 0;
3982 if (ecs->stepped_after_stopped_by_watchpoint)
3983 stopped_by_watchpoint = 0;
3985 stopped_by_watchpoint = watchpoints_triggered (&ecs->ws);
3987 /* If necessary, step over this watchpoint. We'll be back to display
3989 if (stopped_by_watchpoint
3990 && (target_have_steppable_watchpoint
3991 || gdbarch_have_nonsteppable_watchpoint (gdbarch)))
3993 /* At this point, we are stopped at an instruction which has
3994 attempted to write to a piece of memory under control of
3995 a watchpoint. The instruction hasn't actually executed
3996 yet. If we were to evaluate the watchpoint expression
3997 now, we would get the old value, and therefore no change
3998 would seem to have occurred.
4000 In order to make watchpoints work `right', we really need
4001 to complete the memory write, and then evaluate the
4002 watchpoint expression. We do this by single-stepping the
4005 It may not be necessary to disable the watchpoint to step over
4006 it. For example, the PA can (with some kernel cooperation)
4007 single step over a watchpoint without disabling the watchpoint.
4009 It is far more common to need to disable a watchpoint to step
4010 the inferior over it. If we have non-steppable watchpoints,
4011 we must disable the current watchpoint; it's simplest to
4012 disable all watchpoints and breakpoints. */
4015 if (!target_have_steppable_watchpoint)
4017 remove_breakpoints ();
4018 /* See comment in resume why we need to stop bypassing signals
4019 while breakpoints have been removed. */
4020 target_pass_signals (0, NULL);
4023 hw_step = maybe_software_singlestep (gdbarch, stop_pc);
4024 target_resume (ecs->ptid, hw_step, GDB_SIGNAL_0);
4025 waiton_ptid = ecs->ptid;
4026 if (target_have_steppable_watchpoint)
4027 infwait_state = infwait_step_watch_state;
4029 infwait_state = infwait_nonstep_watch_state;
4030 prepare_to_wait (ecs);
4034 ecs->event_thread->stepping_over_breakpoint = 0;
4035 bpstat_clear (&ecs->event_thread->control.stop_bpstat);
4036 ecs->event_thread->control.stop_step = 0;
4037 stop_print_frame = 1;
4038 stopped_by_random_signal = 0;
4040 /* Hide inlined functions starting here, unless we just performed stepi or
4041 nexti. After stepi and nexti, always show the innermost frame (not any
4042 inline function call sites). */
4043 if (ecs->event_thread->control.step_range_end != 1)
4045 struct address_space *aspace =
4046 get_regcache_aspace (get_thread_regcache (ecs->ptid));
4048 /* skip_inline_frames is expensive, so we avoid it if we can
4049 determine that the address is one where functions cannot have
4050 been inlined. This improves performance with inferiors that
4051 load a lot of shared libraries, because the solib event
4052 breakpoint is defined as the address of a function (i.e. not
4053 inline). Note that we have to check the previous PC as well
4054 as the current one to catch cases when we have just
4055 single-stepped off a breakpoint prior to reinstating it.
4056 Note that we're assuming that the code we single-step to is
4057 not inline, but that's not definitive: there's nothing
4058 preventing the event breakpoint function from containing
4059 inlined code, and the single-step ending up there. If the
4060 user had set a breakpoint on that inlined code, the missing
4061 skip_inline_frames call would break things. Fortunately
4062 that's an extremely unlikely scenario. */
4063 if (!pc_at_non_inline_function (aspace, stop_pc, &ecs->ws)
4064 && !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
4065 && ecs->event_thread->control.trap_expected
4066 && pc_at_non_inline_function (aspace,
4067 ecs->event_thread->prev_pc,
4070 skip_inline_frames (ecs->ptid);
4072 /* Re-fetch current thread's frame in case that invalidated
4074 frame = get_current_frame ();
4075 gdbarch = get_frame_arch (frame);
4079 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
4080 && ecs->event_thread->control.trap_expected
4081 && gdbarch_single_step_through_delay_p (gdbarch)
4082 && currently_stepping (ecs->event_thread))
4084 /* We're trying to step off a breakpoint. Turns out that we're
4085 also on an instruction that needs to be stepped multiple
4086 times before it's been fully executing. E.g., architectures
4087 with a delay slot. It needs to be stepped twice, once for
4088 the instruction and once for the delay slot. */
4089 int step_through_delay
4090 = gdbarch_single_step_through_delay (gdbarch, frame);
4092 if (debug_infrun && step_through_delay)
4093 fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n");
4094 if (ecs->event_thread->control.step_range_end == 0
4095 && step_through_delay)
4097 /* The user issued a continue when stopped at a breakpoint.
4098 Set up for another trap and get out of here. */
4099 ecs->event_thread->stepping_over_breakpoint = 1;
4103 else if (step_through_delay)
4105 /* The user issued a step when stopped at a breakpoint.
4106 Maybe we should stop, maybe we should not - the delay
4107 slot *might* correspond to a line of source. In any
4108 case, don't decide that here, just set
4109 ecs->stepping_over_breakpoint, making sure we
4110 single-step again before breakpoints are re-inserted. */
4111 ecs->event_thread->stepping_over_breakpoint = 1;
4115 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4116 handles this event. */
4117 ecs->event_thread->control.stop_bpstat
4118 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4119 stop_pc, ecs->ptid, &ecs->ws);
4121 /* Following in case break condition called a
4123 stop_print_frame = 1;
4125 /* This is where we handle "moribund" watchpoints. Unlike
4126 software breakpoints traps, hardware watchpoint traps are
4127 always distinguishable from random traps. If no high-level
4128 watchpoint is associated with the reported stop data address
4129 anymore, then the bpstat does not explain the signal ---
4130 simply make sure to ignore it if `stopped_by_watchpoint' is
4134 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
4135 && !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
4137 && stopped_by_watchpoint)
4138 fprintf_unfiltered (gdb_stdlog,
4139 "infrun: no user watchpoint explains "
4140 "watchpoint SIGTRAP, ignoring\n");
4142 /* NOTE: cagney/2003-03-29: These checks for a random signal
4143 at one stage in the past included checks for an inferior
4144 function call's call dummy's return breakpoint. The original
4145 comment, that went with the test, read:
4147 ``End of a stack dummy. Some systems (e.g. Sony news) give
4148 another signal besides SIGTRAP, so check here as well as
4151 If someone ever tries to get call dummys on a
4152 non-executable stack to work (where the target would stop
4153 with something like a SIGSEGV), then those tests might need
4154 to be re-instated. Given, however, that the tests were only
4155 enabled when momentary breakpoints were not being used, I
4156 suspect that it won't be the case.
4158 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4159 be necessary for call dummies on a non-executable stack on
4162 /* See if the breakpoints module can explain the signal. */
4164 = !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
4165 ecs->event_thread->suspend.stop_signal);
4167 /* If not, perhaps stepping/nexting can. */
4169 random_signal = !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
4170 && currently_stepping (ecs->event_thread));
4172 /* Perhaps the thread hit a single-step breakpoint of _another_
4173 thread. Single-step breakpoints are transparent to the
4174 breakpoints module. */
4176 random_signal = !ecs->hit_singlestep_breakpoint;
4178 /* No? Perhaps we got a moribund watchpoint. */
4180 random_signal = !stopped_by_watchpoint;
4182 /* For the program's own signals, act according to
4183 the signal handling tables. */
4187 /* Signal not for debugging purposes. */
4189 struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
4190 enum gdb_signal stop_signal = ecs->event_thread->suspend.stop_signal;
4193 fprintf_unfiltered (gdb_stdlog, "infrun: random signal (%s)\n",
4194 gdb_signal_to_symbol_string (stop_signal));
4196 stopped_by_random_signal = 1;
4198 if (signal_print[ecs->event_thread->suspend.stop_signal])
4200 /* The signal table tells us to print about this signal. */
4202 target_terminal_ours_for_output ();
4203 observer_notify_signal_received (ecs->event_thread->suspend.stop_signal);
4205 /* Always stop on signals if we're either just gaining control
4206 of the program, or the user explicitly requested this thread
4207 to remain stopped. */
4208 if (stop_soon != NO_STOP_QUIETLY
4209 || ecs->event_thread->stop_requested
4211 && signal_stop_state (ecs->event_thread->suspend.stop_signal)))
4216 /* If not going to stop, give terminal back
4217 if we took it away. */
4219 target_terminal_inferior ();
4221 /* Clear the signal if it should not be passed. */
4222 if (signal_program[ecs->event_thread->suspend.stop_signal] == 0)
4223 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
4225 if (ecs->event_thread->prev_pc == stop_pc
4226 && ecs->event_thread->control.trap_expected
4227 && ecs->event_thread->control.step_resume_breakpoint == NULL)
4229 /* We were just starting a new sequence, attempting to
4230 single-step off of a breakpoint and expecting a SIGTRAP.
4231 Instead this signal arrives. This signal will take us out
4232 of the stepping range so GDB needs to remember to, when
4233 the signal handler returns, resume stepping off that
4235 /* To simplify things, "continue" is forced to use the same
4236 code paths as single-step - set a breakpoint at the
4237 signal return address and then, once hit, step off that
4240 fprintf_unfiltered (gdb_stdlog,
4241 "infrun: signal arrived while stepping over "
4244 insert_hp_step_resume_breakpoint_at_frame (frame);
4245 ecs->event_thread->step_after_step_resume_breakpoint = 1;
4246 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4247 ecs->event_thread->control.trap_expected = 0;
4249 /* If we were nexting/stepping some other thread, switch to
4250 it, so that we don't continue it, losing control. */
4251 if (!switch_back_to_stepped_thread (ecs))
4256 if (ecs->event_thread->control.step_range_end != 0
4257 && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_0
4258 && pc_in_thread_step_range (stop_pc, ecs->event_thread)
4259 && frame_id_eq (get_stack_frame_id (frame),
4260 ecs->event_thread->control.step_stack_frame_id)
4261 && ecs->event_thread->control.step_resume_breakpoint == NULL)
4263 /* The inferior is about to take a signal that will take it
4264 out of the single step range. Set a breakpoint at the
4265 current PC (which is presumably where the signal handler
4266 will eventually return) and then allow the inferior to
4269 Note that this is only needed for a signal delivered
4270 while in the single-step range. Nested signals aren't a
4271 problem as they eventually all return. */
4273 fprintf_unfiltered (gdb_stdlog,
4274 "infrun: signal may take us out of "
4275 "single-step range\n");
4277 insert_hp_step_resume_breakpoint_at_frame (frame);
4278 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4279 ecs->event_thread->control.trap_expected = 0;
4284 /* Note: step_resume_breakpoint may be non-NULL. This occures
4285 when either there's a nested signal, or when there's a
4286 pending signal enabled just as the signal handler returns
4287 (leaving the inferior at the step-resume-breakpoint without
4288 actually executing it). Either way continue until the
4289 breakpoint is really hit. */
4291 if (!switch_back_to_stepped_thread (ecs))
4294 fprintf_unfiltered (gdb_stdlog,
4295 "infrun: random signal, keep going\n");
4302 process_event_stop_test (ecs);
4305 /* Come here when we've got some debug event / signal we can explain
4306 (IOW, not a random signal), and test whether it should cause a
4307 stop, or whether we should resume the inferior (transparently).
4308 E.g., could be a breakpoint whose condition evaluates false; we
4309 could be still stepping within the line; etc. */
4312 process_event_stop_test (struct execution_control_state *ecs)
4314 struct symtab_and_line stop_pc_sal;
4315 struct frame_info *frame;
4316 struct gdbarch *gdbarch;
4317 CORE_ADDR jmp_buf_pc;
4318 struct bpstat_what what;
4320 /* Handle cases caused by hitting a breakpoint. */
4322 frame = get_current_frame ();
4323 gdbarch = get_frame_arch (frame);
4325 what = bpstat_what (ecs->event_thread->control.stop_bpstat);
4327 if (what.call_dummy)
4329 stop_stack_dummy = what.call_dummy;
4332 /* If we hit an internal event that triggers symbol changes, the
4333 current frame will be invalidated within bpstat_what (e.g., if we
4334 hit an internal solib event). Re-fetch it. */
4335 frame = get_current_frame ();
4336 gdbarch = get_frame_arch (frame);
4338 switch (what.main_action)
4340 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
4341 /* If we hit the breakpoint at longjmp while stepping, we
4342 install a momentary breakpoint at the target of the
4346 fprintf_unfiltered (gdb_stdlog,
4347 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4349 ecs->event_thread->stepping_over_breakpoint = 1;
4351 if (what.is_longjmp)
4353 struct value *arg_value;
4355 /* If we set the longjmp breakpoint via a SystemTap probe,
4356 then use it to extract the arguments. The destination PC
4357 is the third argument to the probe. */
4358 arg_value = probe_safe_evaluate_at_pc (frame, 2);
4360 jmp_buf_pc = value_as_address (arg_value);
4361 else if (!gdbarch_get_longjmp_target_p (gdbarch)
4362 || !gdbarch_get_longjmp_target (gdbarch,
4363 frame, &jmp_buf_pc))
4366 fprintf_unfiltered (gdb_stdlog,
4367 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4368 "(!gdbarch_get_longjmp_target)\n");
4373 /* Insert a breakpoint at resume address. */
4374 insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc);
4377 check_exception_resume (ecs, frame);
4381 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
4383 struct frame_info *init_frame;
4385 /* There are several cases to consider.
4387 1. The initiating frame no longer exists. In this case we
4388 must stop, because the exception or longjmp has gone too
4391 2. The initiating frame exists, and is the same as the
4392 current frame. We stop, because the exception or longjmp
4395 3. The initiating frame exists and is different from the
4396 current frame. This means the exception or longjmp has
4397 been caught beneath the initiating frame, so keep going.
4399 4. longjmp breakpoint has been placed just to protect
4400 against stale dummy frames and user is not interested in
4401 stopping around longjmps. */
4404 fprintf_unfiltered (gdb_stdlog,
4405 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4407 gdb_assert (ecs->event_thread->control.exception_resume_breakpoint
4409 delete_exception_resume_breakpoint (ecs->event_thread);
4411 if (what.is_longjmp)
4413 check_longjmp_breakpoint_for_call_dummy (ecs->event_thread);
4415 if (!frame_id_p (ecs->event_thread->initiating_frame))
4423 init_frame = frame_find_by_id (ecs->event_thread->initiating_frame);
4427 struct frame_id current_id
4428 = get_frame_id (get_current_frame ());
4429 if (frame_id_eq (current_id,
4430 ecs->event_thread->initiating_frame))
4432 /* Case 2. Fall through. */
4442 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
4444 delete_step_resume_breakpoint (ecs->event_thread);
4446 end_stepping_range (ecs);
4450 case BPSTAT_WHAT_SINGLE:
4452 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
4453 ecs->event_thread->stepping_over_breakpoint = 1;
4454 /* Still need to check other stuff, at least the case where we
4455 are stepping and step out of the right range. */
4458 case BPSTAT_WHAT_STEP_RESUME:
4460 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4462 delete_step_resume_breakpoint (ecs->event_thread);
4463 if (ecs->event_thread->control.proceed_to_finish
4464 && execution_direction == EXEC_REVERSE)
4466 struct thread_info *tp = ecs->event_thread;
4468 /* We are finishing a function in reverse, and just hit the
4469 step-resume breakpoint at the start address of the
4470 function, and we're almost there -- just need to back up
4471 by one more single-step, which should take us back to the
4473 tp->control.step_range_start = tp->control.step_range_end = 1;
4477 fill_in_stop_func (gdbarch, ecs);
4478 if (stop_pc == ecs->stop_func_start
4479 && execution_direction == EXEC_REVERSE)
4481 /* We are stepping over a function call in reverse, and just
4482 hit the step-resume breakpoint at the start address of
4483 the function. Go back to single-stepping, which should
4484 take us back to the function call. */
4485 ecs->event_thread->stepping_over_breakpoint = 1;
4491 case BPSTAT_WHAT_STOP_NOISY:
4493 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4494 stop_print_frame = 1;
4496 /* Assume the thread stopped for a breapoint. We'll still check
4497 whether a/the breakpoint is there when the thread is next
4499 ecs->event_thread->stepping_over_breakpoint = 1;
4504 case BPSTAT_WHAT_STOP_SILENT:
4506 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4507 stop_print_frame = 0;
4509 /* Assume the thread stopped for a breapoint. We'll still check
4510 whether a/the breakpoint is there when the thread is next
4512 ecs->event_thread->stepping_over_breakpoint = 1;
4516 case BPSTAT_WHAT_HP_STEP_RESUME:
4518 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4520 delete_step_resume_breakpoint (ecs->event_thread);
4521 if (ecs->event_thread->step_after_step_resume_breakpoint)
4523 /* Back when the step-resume breakpoint was inserted, we
4524 were trying to single-step off a breakpoint. Go back to
4526 ecs->event_thread->step_after_step_resume_breakpoint = 0;
4527 ecs->event_thread->stepping_over_breakpoint = 1;
4533 case BPSTAT_WHAT_KEEP_CHECKING:
4537 /* We come here if we hit a breakpoint but should not stop for it.
4538 Possibly we also were stepping and should stop for that. So fall
4539 through and test for stepping. But, if not stepping, do not
4542 /* In all-stop mode, if we're currently stepping but have stopped in
4543 some other thread, we need to switch back to the stepped thread. */
4544 if (switch_back_to_stepped_thread (ecs))
4547 if (ecs->event_thread->control.step_resume_breakpoint)
4550 fprintf_unfiltered (gdb_stdlog,
4551 "infrun: step-resume breakpoint is inserted\n");
4553 /* Having a step-resume breakpoint overrides anything
4554 else having to do with stepping commands until
4555 that breakpoint is reached. */
4560 if (ecs->event_thread->control.step_range_end == 0)
4563 fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n");
4564 /* Likewise if we aren't even stepping. */
4569 /* Re-fetch current thread's frame in case the code above caused
4570 the frame cache to be re-initialized, making our FRAME variable
4571 a dangling pointer. */
4572 frame = get_current_frame ();
4573 gdbarch = get_frame_arch (frame);
4574 fill_in_stop_func (gdbarch, ecs);
4576 /* If stepping through a line, keep going if still within it.
4578 Note that step_range_end is the address of the first instruction
4579 beyond the step range, and NOT the address of the last instruction
4582 Note also that during reverse execution, we may be stepping
4583 through a function epilogue and therefore must detect when
4584 the current-frame changes in the middle of a line. */
4586 if (pc_in_thread_step_range (stop_pc, ecs->event_thread)
4587 && (execution_direction != EXEC_REVERSE
4588 || frame_id_eq (get_frame_id (frame),
4589 ecs->event_thread->control.step_frame_id)))
4593 (gdb_stdlog, "infrun: stepping inside range [%s-%s]\n",
4594 paddress (gdbarch, ecs->event_thread->control.step_range_start),
4595 paddress (gdbarch, ecs->event_thread->control.step_range_end));
4597 /* Tentatively re-enable range stepping; `resume' disables it if
4598 necessary (e.g., if we're stepping over a breakpoint or we
4599 have software watchpoints). */
4600 ecs->event_thread->control.may_range_step = 1;
4602 /* When stepping backward, stop at beginning of line range
4603 (unless it's the function entry point, in which case
4604 keep going back to the call point). */
4605 if (stop_pc == ecs->event_thread->control.step_range_start
4606 && stop_pc != ecs->stop_func_start
4607 && execution_direction == EXEC_REVERSE)
4608 end_stepping_range (ecs);
4615 /* We stepped out of the stepping range. */
4617 /* If we are stepping at the source level and entered the runtime
4618 loader dynamic symbol resolution code...
4620 EXEC_FORWARD: we keep on single stepping until we exit the run
4621 time loader code and reach the callee's address.
4623 EXEC_REVERSE: we've already executed the callee (backward), and
4624 the runtime loader code is handled just like any other
4625 undebuggable function call. Now we need only keep stepping
4626 backward through the trampoline code, and that's handled further
4627 down, so there is nothing for us to do here. */
4629 if (execution_direction != EXEC_REVERSE
4630 && ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
4631 && in_solib_dynsym_resolve_code (stop_pc))
4633 CORE_ADDR pc_after_resolver =
4634 gdbarch_skip_solib_resolver (gdbarch, stop_pc);
4637 fprintf_unfiltered (gdb_stdlog,
4638 "infrun: stepped into dynsym resolve code\n");
4640 if (pc_after_resolver)
4642 /* Set up a step-resume breakpoint at the address
4643 indicated by SKIP_SOLIB_RESOLVER. */
4644 struct symtab_and_line sr_sal;
4647 sr_sal.pc = pc_after_resolver;
4648 sr_sal.pspace = get_frame_program_space (frame);
4650 insert_step_resume_breakpoint_at_sal (gdbarch,
4651 sr_sal, null_frame_id);
4658 if (ecs->event_thread->control.step_range_end != 1
4659 && (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
4660 || ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
4661 && get_frame_type (frame) == SIGTRAMP_FRAME)
4664 fprintf_unfiltered (gdb_stdlog,
4665 "infrun: stepped into signal trampoline\n");
4666 /* The inferior, while doing a "step" or "next", has ended up in
4667 a signal trampoline (either by a signal being delivered or by
4668 the signal handler returning). Just single-step until the
4669 inferior leaves the trampoline (either by calling the handler
4675 /* If we're in the return path from a shared library trampoline,
4676 we want to proceed through the trampoline when stepping. */
4677 /* macro/2012-04-25: This needs to come before the subroutine
4678 call check below as on some targets return trampolines look
4679 like subroutine calls (MIPS16 return thunks). */
4680 if (gdbarch_in_solib_return_trampoline (gdbarch,
4681 stop_pc, ecs->stop_func_name)
4682 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
4684 /* Determine where this trampoline returns. */
4685 CORE_ADDR real_stop_pc;
4687 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
4690 fprintf_unfiltered (gdb_stdlog,
4691 "infrun: stepped into solib return tramp\n");
4693 /* Only proceed through if we know where it's going. */
4696 /* And put the step-breakpoint there and go until there. */
4697 struct symtab_and_line sr_sal;
4699 init_sal (&sr_sal); /* initialize to zeroes */
4700 sr_sal.pc = real_stop_pc;
4701 sr_sal.section = find_pc_overlay (sr_sal.pc);
4702 sr_sal.pspace = get_frame_program_space (frame);
4704 /* Do not specify what the fp should be when we stop since
4705 on some machines the prologue is where the new fp value
4707 insert_step_resume_breakpoint_at_sal (gdbarch,
4708 sr_sal, null_frame_id);
4710 /* Restart without fiddling with the step ranges or
4717 /* Check for subroutine calls. The check for the current frame
4718 equalling the step ID is not necessary - the check of the
4719 previous frame's ID is sufficient - but it is a common case and
4720 cheaper than checking the previous frame's ID.
4722 NOTE: frame_id_eq will never report two invalid frame IDs as
4723 being equal, so to get into this block, both the current and
4724 previous frame must have valid frame IDs. */
4725 /* The outer_frame_id check is a heuristic to detect stepping
4726 through startup code. If we step over an instruction which
4727 sets the stack pointer from an invalid value to a valid value,
4728 we may detect that as a subroutine call from the mythical
4729 "outermost" function. This could be fixed by marking
4730 outermost frames as !stack_p,code_p,special_p. Then the
4731 initial outermost frame, before sp was valid, would
4732 have code_addr == &_start. See the comment in frame_id_eq
4734 if (!frame_id_eq (get_stack_frame_id (frame),
4735 ecs->event_thread->control.step_stack_frame_id)
4736 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4737 ecs->event_thread->control.step_stack_frame_id)
4738 && (!frame_id_eq (ecs->event_thread->control.step_stack_frame_id,
4740 || step_start_function != find_pc_function (stop_pc))))
4742 CORE_ADDR real_stop_pc;
4745 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n");
4747 if ((ecs->event_thread->control.step_over_calls == STEP_OVER_NONE)
4748 || ((ecs->event_thread->control.step_range_end == 1)
4749 && in_prologue (gdbarch, ecs->event_thread->prev_pc,
4750 ecs->stop_func_start)))
4752 /* I presume that step_over_calls is only 0 when we're
4753 supposed to be stepping at the assembly language level
4754 ("stepi"). Just stop. */
4755 /* Also, maybe we just did a "nexti" inside a prolog, so we
4756 thought it was a subroutine call but it was not. Stop as
4758 /* And this works the same backward as frontward. MVS */
4759 end_stepping_range (ecs);
4763 /* Reverse stepping through solib trampolines. */
4765 if (execution_direction == EXEC_REVERSE
4766 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE
4767 && (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
4768 || (ecs->stop_func_start == 0
4769 && in_solib_dynsym_resolve_code (stop_pc))))
4771 /* Any solib trampoline code can be handled in reverse
4772 by simply continuing to single-step. We have already
4773 executed the solib function (backwards), and a few
4774 steps will take us back through the trampoline to the
4780 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
4782 /* We're doing a "next".
4784 Normal (forward) execution: set a breakpoint at the
4785 callee's return address (the address at which the caller
4788 Reverse (backward) execution. set the step-resume
4789 breakpoint at the start of the function that we just
4790 stepped into (backwards), and continue to there. When we
4791 get there, we'll need to single-step back to the caller. */
4793 if (execution_direction == EXEC_REVERSE)
4795 /* If we're already at the start of the function, we've either
4796 just stepped backward into a single instruction function,
4797 or stepped back out of a signal handler to the first instruction
4798 of the function. Just keep going, which will single-step back
4800 if (ecs->stop_func_start != stop_pc && ecs->stop_func_start != 0)
4802 struct symtab_and_line sr_sal;
4804 /* Normal function call return (static or dynamic). */
4806 sr_sal.pc = ecs->stop_func_start;
4807 sr_sal.pspace = get_frame_program_space (frame);
4808 insert_step_resume_breakpoint_at_sal (gdbarch,
4809 sr_sal, null_frame_id);
4813 insert_step_resume_breakpoint_at_caller (frame);
4819 /* If we are in a function call trampoline (a stub between the
4820 calling routine and the real function), locate the real
4821 function. That's what tells us (a) whether we want to step
4822 into it at all, and (b) what prologue we want to run to the
4823 end of, if we do step into it. */
4824 real_stop_pc = skip_language_trampoline (frame, stop_pc);
4825 if (real_stop_pc == 0)
4826 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
4827 if (real_stop_pc != 0)
4828 ecs->stop_func_start = real_stop_pc;
4830 if (real_stop_pc != 0 && in_solib_dynsym_resolve_code (real_stop_pc))
4832 struct symtab_and_line sr_sal;
4835 sr_sal.pc = ecs->stop_func_start;
4836 sr_sal.pspace = get_frame_program_space (frame);
4838 insert_step_resume_breakpoint_at_sal (gdbarch,
4839 sr_sal, null_frame_id);
4844 /* If we have line number information for the function we are
4845 thinking of stepping into and the function isn't on the skip
4848 If there are several symtabs at that PC (e.g. with include
4849 files), just want to know whether *any* of them have line
4850 numbers. find_pc_line handles this. */
4852 struct symtab_and_line tmp_sal;
4854 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
4855 if (tmp_sal.line != 0
4856 && !function_name_is_marked_for_skip (ecs->stop_func_name,
4859 if (execution_direction == EXEC_REVERSE)
4860 handle_step_into_function_backward (gdbarch, ecs);
4862 handle_step_into_function (gdbarch, ecs);
4867 /* If we have no line number and the step-stop-if-no-debug is
4868 set, we stop the step so that the user has a chance to switch
4869 in assembly mode. */
4870 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
4871 && step_stop_if_no_debug)
4873 end_stepping_range (ecs);
4877 if (execution_direction == EXEC_REVERSE)
4879 /* If we're already at the start of the function, we've either just
4880 stepped backward into a single instruction function without line
4881 number info, or stepped back out of a signal handler to the first
4882 instruction of the function without line number info. Just keep
4883 going, which will single-step back to the caller. */
4884 if (ecs->stop_func_start != stop_pc)
4886 /* Set a breakpoint at callee's start address.
4887 From there we can step once and be back in the caller. */
4888 struct symtab_and_line sr_sal;
4891 sr_sal.pc = ecs->stop_func_start;
4892 sr_sal.pspace = get_frame_program_space (frame);
4893 insert_step_resume_breakpoint_at_sal (gdbarch,
4894 sr_sal, null_frame_id);
4898 /* Set a breakpoint at callee's return address (the address
4899 at which the caller will resume). */
4900 insert_step_resume_breakpoint_at_caller (frame);
4906 /* Reverse stepping through solib trampolines. */
4908 if (execution_direction == EXEC_REVERSE
4909 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
4911 if (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
4912 || (ecs->stop_func_start == 0
4913 && in_solib_dynsym_resolve_code (stop_pc)))
4915 /* Any solib trampoline code can be handled in reverse
4916 by simply continuing to single-step. We have already
4917 executed the solib function (backwards), and a few
4918 steps will take us back through the trampoline to the
4923 else if (in_solib_dynsym_resolve_code (stop_pc))
4925 /* Stepped backward into the solib dynsym resolver.
4926 Set a breakpoint at its start and continue, then
4927 one more step will take us out. */
4928 struct symtab_and_line sr_sal;
4931 sr_sal.pc = ecs->stop_func_start;
4932 sr_sal.pspace = get_frame_program_space (frame);
4933 insert_step_resume_breakpoint_at_sal (gdbarch,
4934 sr_sal, null_frame_id);
4940 stop_pc_sal = find_pc_line (stop_pc, 0);
4942 /* NOTE: tausq/2004-05-24: This if block used to be done before all
4943 the trampoline processing logic, however, there are some trampolines
4944 that have no names, so we should do trampoline handling first. */
4945 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
4946 && ecs->stop_func_name == NULL
4947 && stop_pc_sal.line == 0)
4950 fprintf_unfiltered (gdb_stdlog,
4951 "infrun: stepped into undebuggable function\n");
4953 /* The inferior just stepped into, or returned to, an
4954 undebuggable function (where there is no debugging information
4955 and no line number corresponding to the address where the
4956 inferior stopped). Since we want to skip this kind of code,
4957 we keep going until the inferior returns from this
4958 function - unless the user has asked us not to (via
4959 set step-mode) or we no longer know how to get back
4960 to the call site. */
4961 if (step_stop_if_no_debug
4962 || !frame_id_p (frame_unwind_caller_id (frame)))
4964 /* If we have no line number and the step-stop-if-no-debug
4965 is set, we stop the step so that the user has a chance to
4966 switch in assembly mode. */
4967 end_stepping_range (ecs);
4972 /* Set a breakpoint at callee's return address (the address
4973 at which the caller will resume). */
4974 insert_step_resume_breakpoint_at_caller (frame);
4980 if (ecs->event_thread->control.step_range_end == 1)
4982 /* It is stepi or nexti. We always want to stop stepping after
4985 fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
4986 end_stepping_range (ecs);
4990 if (stop_pc_sal.line == 0)
4992 /* We have no line number information. That means to stop
4993 stepping (does this always happen right after one instruction,
4994 when we do "s" in a function with no line numbers,
4995 or can this happen as a result of a return or longjmp?). */
4997 fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n");
4998 end_stepping_range (ecs);
5002 /* Look for "calls" to inlined functions, part one. If the inline
5003 frame machinery detected some skipped call sites, we have entered
5004 a new inline function. */
5006 if (frame_id_eq (get_frame_id (get_current_frame ()),
5007 ecs->event_thread->control.step_frame_id)
5008 && inline_skipped_frames (ecs->ptid))
5010 struct symtab_and_line call_sal;
5013 fprintf_unfiltered (gdb_stdlog,
5014 "infrun: stepped into inlined function\n");
5016 find_frame_sal (get_current_frame (), &call_sal);
5018 if (ecs->event_thread->control.step_over_calls != STEP_OVER_ALL)
5020 /* For "step", we're going to stop. But if the call site
5021 for this inlined function is on the same source line as
5022 we were previously stepping, go down into the function
5023 first. Otherwise stop at the call site. */
5025 if (call_sal.line == ecs->event_thread->current_line
5026 && call_sal.symtab == ecs->event_thread->current_symtab)
5027 step_into_inline_frame (ecs->ptid);
5029 end_stepping_range (ecs);
5034 /* For "next", we should stop at the call site if it is on a
5035 different source line. Otherwise continue through the
5036 inlined function. */
5037 if (call_sal.line == ecs->event_thread->current_line
5038 && call_sal.symtab == ecs->event_thread->current_symtab)
5041 end_stepping_range (ecs);
5046 /* Look for "calls" to inlined functions, part two. If we are still
5047 in the same real function we were stepping through, but we have
5048 to go further up to find the exact frame ID, we are stepping
5049 through a more inlined call beyond its call site. */
5051 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5052 && !frame_id_eq (get_frame_id (get_current_frame ()),
5053 ecs->event_thread->control.step_frame_id)
5054 && stepped_in_from (get_current_frame (),
5055 ecs->event_thread->control.step_frame_id))
5058 fprintf_unfiltered (gdb_stdlog,
5059 "infrun: stepping through inlined function\n");
5061 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
5064 end_stepping_range (ecs);
5068 if ((stop_pc == stop_pc_sal.pc)
5069 && (ecs->event_thread->current_line != stop_pc_sal.line
5070 || ecs->event_thread->current_symtab != stop_pc_sal.symtab))
5072 /* We are at the start of a different line. So stop. Note that
5073 we don't stop if we step into the middle of a different line.
5074 That is said to make things like for (;;) statements work
5077 fprintf_unfiltered (gdb_stdlog,
5078 "infrun: stepped to a different line\n");
5079 end_stepping_range (ecs);
5083 /* We aren't done stepping.
5085 Optimize by setting the stepping range to the line.
5086 (We might not be in the original line, but if we entered a
5087 new line in mid-statement, we continue stepping. This makes
5088 things like for(;;) statements work better.) */
5090 ecs->event_thread->control.step_range_start = stop_pc_sal.pc;
5091 ecs->event_thread->control.step_range_end = stop_pc_sal.end;
5092 ecs->event_thread->control.may_range_step = 1;
5093 set_step_info (frame, stop_pc_sal);
5096 fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n");
5100 /* In all-stop mode, if we're currently stepping but have stopped in
5101 some other thread, we may need to switch back to the stepped
5102 thread. Returns true we set the inferior running, false if we left
5103 it stopped (and the event needs further processing). */
5106 switch_back_to_stepped_thread (struct execution_control_state *ecs)
5110 struct thread_info *tp;
5111 struct thread_info *stepping_thread;
5112 struct thread_info *step_over;
5114 /* If any thread is blocked on some internal breakpoint, and we
5115 simply need to step over that breakpoint to get it going
5116 again, do that first. */
5118 /* However, if we see an event for the stepping thread, then we
5119 know all other threads have been moved past their breakpoints
5120 already. Let the caller check whether the step is finished,
5121 etc., before deciding to move it past a breakpoint. */
5122 if (ecs->event_thread->control.step_range_end != 0)
5125 /* Check if the current thread is blocked on an incomplete
5126 step-over, interrupted by a random signal. */
5127 if (ecs->event_thread->control.trap_expected
5128 && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_TRAP)
5132 fprintf_unfiltered (gdb_stdlog,
5133 "infrun: need to finish step-over of [%s]\n",
5134 target_pid_to_str (ecs->event_thread->ptid));
5140 /* Check if the current thread is blocked by a single-step
5141 breakpoint of another thread. */
5142 if (ecs->hit_singlestep_breakpoint)
5146 fprintf_unfiltered (gdb_stdlog,
5147 "infrun: need to step [%s] over single-step "
5149 target_pid_to_str (ecs->ptid));
5155 /* Otherwise, we no longer expect a trap in the current thread.
5156 Clear the trap_expected flag before switching back -- this is
5157 what keep_going does as well, if we call it. */
5158 ecs->event_thread->control.trap_expected = 0;
5160 /* Likewise, clear the signal if it should not be passed. */
5161 if (!signal_program[ecs->event_thread->suspend.stop_signal])
5162 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5164 /* If scheduler locking applies even if not stepping, there's no
5165 need to walk over threads. Above we've checked whether the
5166 current thread is stepping. If some other thread not the
5167 event thread is stepping, then it must be that scheduler
5168 locking is not in effect. */
5169 if (schedlock_applies (0))
5172 /* Look for the stepping/nexting thread, and check if any other
5173 thread other than the stepping thread needs to start a
5174 step-over. Do all step-overs before actually proceeding with
5176 stepping_thread = NULL;
5178 ALL_NON_EXITED_THREADS (tp)
5180 /* Ignore threads of processes we're not resuming. */
5182 && ptid_get_pid (tp->ptid) != ptid_get_pid (inferior_ptid))
5185 /* When stepping over a breakpoint, we lock all threads
5186 except the one that needs to move past the breakpoint.
5187 If a non-event thread has this set, the "incomplete
5188 step-over" check above should have caught it earlier. */
5189 gdb_assert (!tp->control.trap_expected);
5191 /* Did we find the stepping thread? */
5192 if (tp->control.step_range_end)
5194 /* Yep. There should only one though. */
5195 gdb_assert (stepping_thread == NULL);
5197 /* The event thread is handled at the top, before we
5199 gdb_assert (tp != ecs->event_thread);
5201 /* If some thread other than the event thread is
5202 stepping, then scheduler locking can't be in effect,
5203 otherwise we wouldn't have resumed the current event
5204 thread in the first place. */
5205 gdb_assert (!schedlock_applies (1));
5207 stepping_thread = tp;
5209 else if (thread_still_needs_step_over (tp))
5213 /* At the top we've returned early if the event thread
5214 is stepping. If some other thread not the event
5215 thread is stepping, then scheduler locking can't be
5216 in effect, and we can resume this thread. No need to
5217 keep looking for the stepping thread then. */
5222 if (step_over != NULL)
5227 fprintf_unfiltered (gdb_stdlog,
5228 "infrun: need to step-over [%s]\n",
5229 target_pid_to_str (tp->ptid));
5232 /* Only the stepping thread should have this set. */
5233 gdb_assert (tp->control.step_range_end == 0);
5235 ecs->ptid = tp->ptid;
5236 ecs->event_thread = tp;
5237 switch_to_thread (ecs->ptid);
5242 if (stepping_thread != NULL)
5244 struct frame_info *frame;
5245 struct gdbarch *gdbarch;
5247 tp = stepping_thread;
5249 /* If the stepping thread exited, then don't try to switch
5250 back and resume it, which could fail in several different
5251 ways depending on the target. Instead, just keep going.
5253 We can find a stepping dead thread in the thread list in
5256 - The target supports thread exit events, and when the
5257 target tries to delete the thread from the thread list,
5258 inferior_ptid pointed at the exiting thread. In such
5259 case, calling delete_thread does not really remove the
5260 thread from the list; instead, the thread is left listed,
5261 with 'exited' state.
5263 - The target's debug interface does not support thread
5264 exit events, and so we have no idea whatsoever if the
5265 previously stepping thread is still alive. For that
5266 reason, we need to synchronously query the target
5268 if (is_exited (tp->ptid)
5269 || !target_thread_alive (tp->ptid))
5272 fprintf_unfiltered (gdb_stdlog,
5273 "infrun: not switching back to "
5274 "stepped thread, it has vanished\n");
5276 delete_thread (tp->ptid);
5282 fprintf_unfiltered (gdb_stdlog,
5283 "infrun: switching back to stepped thread\n");
5285 ecs->event_thread = tp;
5286 ecs->ptid = tp->ptid;
5287 context_switch (ecs->ptid);
5289 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
5290 frame = get_current_frame ();
5291 gdbarch = get_frame_arch (frame);
5293 /* If the PC of the thread we were trying to single-step has
5294 changed, then that thread has trapped or been signaled,
5295 but the event has not been reported to GDB yet. Re-poll
5296 the target looking for this particular thread's event
5297 (i.e. temporarily enable schedlock) by:
5299 - setting a break at the current PC
5300 - resuming that particular thread, only (by setting
5303 This prevents us continuously moving the single-step
5304 breakpoint forward, one instruction at a time,
5307 if (gdbarch_software_single_step_p (gdbarch)
5308 && stop_pc != tp->prev_pc)
5311 fprintf_unfiltered (gdb_stdlog,
5312 "infrun: expected thread advanced also\n");
5314 insert_single_step_breakpoint (get_frame_arch (frame),
5315 get_frame_address_space (frame),
5317 singlestep_breakpoints_inserted_p = 1;
5318 ecs->event_thread->control.trap_expected = 1;
5319 singlestep_ptid = inferior_ptid;
5320 singlestep_pc = stop_pc;
5322 resume (0, GDB_SIGNAL_0);
5323 prepare_to_wait (ecs);
5328 fprintf_unfiltered (gdb_stdlog,
5329 "infrun: expected thread still "
5330 "hasn't advanced\n");
5340 /* Is thread TP in the middle of single-stepping? */
5343 currently_stepping (struct thread_info *tp)
5345 return ((tp->control.step_range_end
5346 && tp->control.step_resume_breakpoint == NULL)
5347 || tp->control.trap_expected
5348 || bpstat_should_step ());
5351 /* Inferior has stepped into a subroutine call with source code that
5352 we should not step over. Do step to the first line of code in
5356 handle_step_into_function (struct gdbarch *gdbarch,
5357 struct execution_control_state *ecs)
5360 struct symtab_and_line stop_func_sal, sr_sal;
5362 fill_in_stop_func (gdbarch, ecs);
5364 s = find_pc_symtab (stop_pc);
5365 if (s && s->language != language_asm)
5366 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
5367 ecs->stop_func_start);
5369 stop_func_sal = find_pc_line (ecs->stop_func_start, 0);
5370 /* Use the step_resume_break to step until the end of the prologue,
5371 even if that involves jumps (as it seems to on the vax under
5373 /* If the prologue ends in the middle of a source line, continue to
5374 the end of that source line (if it is still within the function).
5375 Otherwise, just go to end of prologue. */
5376 if (stop_func_sal.end
5377 && stop_func_sal.pc != ecs->stop_func_start
5378 && stop_func_sal.end < ecs->stop_func_end)
5379 ecs->stop_func_start = stop_func_sal.end;
5381 /* Architectures which require breakpoint adjustment might not be able
5382 to place a breakpoint at the computed address. If so, the test
5383 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5384 ecs->stop_func_start to an address at which a breakpoint may be
5385 legitimately placed.
5387 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5388 made, GDB will enter an infinite loop when stepping through
5389 optimized code consisting of VLIW instructions which contain
5390 subinstructions corresponding to different source lines. On
5391 FR-V, it's not permitted to place a breakpoint on any but the
5392 first subinstruction of a VLIW instruction. When a breakpoint is
5393 set, GDB will adjust the breakpoint address to the beginning of
5394 the VLIW instruction. Thus, we need to make the corresponding
5395 adjustment here when computing the stop address. */
5397 if (gdbarch_adjust_breakpoint_address_p (gdbarch))
5399 ecs->stop_func_start
5400 = gdbarch_adjust_breakpoint_address (gdbarch,
5401 ecs->stop_func_start);
5404 if (ecs->stop_func_start == stop_pc)
5406 /* We are already there: stop now. */
5407 end_stepping_range (ecs);
5412 /* Put the step-breakpoint there and go until there. */
5413 init_sal (&sr_sal); /* initialize to zeroes */
5414 sr_sal.pc = ecs->stop_func_start;
5415 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
5416 sr_sal.pspace = get_frame_program_space (get_current_frame ());
5418 /* Do not specify what the fp should be when we stop since on
5419 some machines the prologue is where the new fp value is
5421 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal, null_frame_id);
5423 /* And make sure stepping stops right away then. */
5424 ecs->event_thread->control.step_range_end
5425 = ecs->event_thread->control.step_range_start;
5430 /* Inferior has stepped backward into a subroutine call with source
5431 code that we should not step over. Do step to the beginning of the
5432 last line of code in it. */
5435 handle_step_into_function_backward (struct gdbarch *gdbarch,
5436 struct execution_control_state *ecs)
5439 struct symtab_and_line stop_func_sal;
5441 fill_in_stop_func (gdbarch, ecs);
5443 s = find_pc_symtab (stop_pc);
5444 if (s && s->language != language_asm)
5445 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
5446 ecs->stop_func_start);
5448 stop_func_sal = find_pc_line (stop_pc, 0);
5450 /* OK, we're just going to keep stepping here. */
5451 if (stop_func_sal.pc == stop_pc)
5453 /* We're there already. Just stop stepping now. */
5454 end_stepping_range (ecs);
5458 /* Else just reset the step range and keep going.
5459 No step-resume breakpoint, they don't work for
5460 epilogues, which can have multiple entry paths. */
5461 ecs->event_thread->control.step_range_start = stop_func_sal.pc;
5462 ecs->event_thread->control.step_range_end = stop_func_sal.end;
5468 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5469 This is used to both functions and to skip over code. */
5472 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch *gdbarch,
5473 struct symtab_and_line sr_sal,
5474 struct frame_id sr_id,
5475 enum bptype sr_type)
5477 /* There should never be more than one step-resume or longjmp-resume
5478 breakpoint per thread, so we should never be setting a new
5479 step_resume_breakpoint when one is already active. */
5480 gdb_assert (inferior_thread ()->control.step_resume_breakpoint == NULL);
5481 gdb_assert (sr_type == bp_step_resume || sr_type == bp_hp_step_resume);
5484 fprintf_unfiltered (gdb_stdlog,
5485 "infrun: inserting step-resume breakpoint at %s\n",
5486 paddress (gdbarch, sr_sal.pc));
5488 inferior_thread ()->control.step_resume_breakpoint
5489 = set_momentary_breakpoint (gdbarch, sr_sal, sr_id, sr_type);
5493 insert_step_resume_breakpoint_at_sal (struct gdbarch *gdbarch,
5494 struct symtab_and_line sr_sal,
5495 struct frame_id sr_id)
5497 insert_step_resume_breakpoint_at_sal_1 (gdbarch,
5502 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5503 This is used to skip a potential signal handler.
5505 This is called with the interrupted function's frame. The signal
5506 handler, when it returns, will resume the interrupted function at
5510 insert_hp_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
5512 struct symtab_and_line sr_sal;
5513 struct gdbarch *gdbarch;
5515 gdb_assert (return_frame != NULL);
5516 init_sal (&sr_sal); /* initialize to zeros */
5518 gdbarch = get_frame_arch (return_frame);
5519 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch, get_frame_pc (return_frame));
5520 sr_sal.section = find_pc_overlay (sr_sal.pc);
5521 sr_sal.pspace = get_frame_program_space (return_frame);
5523 insert_step_resume_breakpoint_at_sal_1 (gdbarch, sr_sal,
5524 get_stack_frame_id (return_frame),
5528 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5529 is used to skip a function after stepping into it (for "next" or if
5530 the called function has no debugging information).
5532 The current function has almost always been reached by single
5533 stepping a call or return instruction. NEXT_FRAME belongs to the
5534 current function, and the breakpoint will be set at the caller's
5537 This is a separate function rather than reusing
5538 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5539 get_prev_frame, which may stop prematurely (see the implementation
5540 of frame_unwind_caller_id for an example). */
5543 insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame)
5545 struct symtab_and_line sr_sal;
5546 struct gdbarch *gdbarch;
5548 /* We shouldn't have gotten here if we don't know where the call site
5550 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame)));
5552 init_sal (&sr_sal); /* initialize to zeros */
5554 gdbarch = frame_unwind_caller_arch (next_frame);
5555 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch,
5556 frame_unwind_caller_pc (next_frame));
5557 sr_sal.section = find_pc_overlay (sr_sal.pc);
5558 sr_sal.pspace = frame_unwind_program_space (next_frame);
5560 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal,
5561 frame_unwind_caller_id (next_frame));
5564 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5565 new breakpoint at the target of a jmp_buf. The handling of
5566 longjmp-resume uses the same mechanisms used for handling
5567 "step-resume" breakpoints. */
5570 insert_longjmp_resume_breakpoint (struct gdbarch *gdbarch, CORE_ADDR pc)
5572 /* There should never be more than one longjmp-resume breakpoint per
5573 thread, so we should never be setting a new
5574 longjmp_resume_breakpoint when one is already active. */
5575 gdb_assert (inferior_thread ()->control.exception_resume_breakpoint == NULL);
5578 fprintf_unfiltered (gdb_stdlog,
5579 "infrun: inserting longjmp-resume breakpoint at %s\n",
5580 paddress (gdbarch, pc));
5582 inferior_thread ()->control.exception_resume_breakpoint =
5583 set_momentary_breakpoint_at_pc (gdbarch, pc, bp_longjmp_resume);
5586 /* Insert an exception resume breakpoint. TP is the thread throwing
5587 the exception. The block B is the block of the unwinder debug hook
5588 function. FRAME is the frame corresponding to the call to this
5589 function. SYM is the symbol of the function argument holding the
5590 target PC of the exception. */
5593 insert_exception_resume_breakpoint (struct thread_info *tp,
5594 const struct block *b,
5595 struct frame_info *frame,
5598 volatile struct gdb_exception e;
5600 /* We want to ignore errors here. */
5601 TRY_CATCH (e, RETURN_MASK_ERROR)
5603 struct symbol *vsym;
5604 struct value *value;
5606 struct breakpoint *bp;
5608 vsym = lookup_symbol (SYMBOL_LINKAGE_NAME (sym), b, VAR_DOMAIN, NULL);
5609 value = read_var_value (vsym, frame);
5610 /* If the value was optimized out, revert to the old behavior. */
5611 if (! value_optimized_out (value))
5613 handler = value_as_address (value);
5616 fprintf_unfiltered (gdb_stdlog,
5617 "infrun: exception resume at %lx\n",
5618 (unsigned long) handler);
5620 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
5621 handler, bp_exception_resume);
5623 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5626 bp->thread = tp->num;
5627 inferior_thread ()->control.exception_resume_breakpoint = bp;
5632 /* A helper for check_exception_resume that sets an
5633 exception-breakpoint based on a SystemTap probe. */
5636 insert_exception_resume_from_probe (struct thread_info *tp,
5637 const struct bound_probe *probe,
5638 struct frame_info *frame)
5640 struct value *arg_value;
5642 struct breakpoint *bp;
5644 arg_value = probe_safe_evaluate_at_pc (frame, 1);
5648 handler = value_as_address (arg_value);
5651 fprintf_unfiltered (gdb_stdlog,
5652 "infrun: exception resume at %s\n",
5653 paddress (get_objfile_arch (probe->objfile),
5656 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
5657 handler, bp_exception_resume);
5658 bp->thread = tp->num;
5659 inferior_thread ()->control.exception_resume_breakpoint = bp;
5662 /* This is called when an exception has been intercepted. Check to
5663 see whether the exception's destination is of interest, and if so,
5664 set an exception resume breakpoint there. */
5667 check_exception_resume (struct execution_control_state *ecs,
5668 struct frame_info *frame)
5670 volatile struct gdb_exception e;
5671 struct bound_probe probe;
5672 struct symbol *func;
5674 /* First see if this exception unwinding breakpoint was set via a
5675 SystemTap probe point. If so, the probe has two arguments: the
5676 CFA and the HANDLER. We ignore the CFA, extract the handler, and
5677 set a breakpoint there. */
5678 probe = find_probe_by_pc (get_frame_pc (frame));
5681 insert_exception_resume_from_probe (ecs->event_thread, &probe, frame);
5685 func = get_frame_function (frame);
5689 TRY_CATCH (e, RETURN_MASK_ERROR)
5691 const struct block *b;
5692 struct block_iterator iter;
5696 /* The exception breakpoint is a thread-specific breakpoint on
5697 the unwinder's debug hook, declared as:
5699 void _Unwind_DebugHook (void *cfa, void *handler);
5701 The CFA argument indicates the frame to which control is
5702 about to be transferred. HANDLER is the destination PC.
5704 We ignore the CFA and set a temporary breakpoint at HANDLER.
5705 This is not extremely efficient but it avoids issues in gdb
5706 with computing the DWARF CFA, and it also works even in weird
5707 cases such as throwing an exception from inside a signal
5710 b = SYMBOL_BLOCK_VALUE (func);
5711 ALL_BLOCK_SYMBOLS (b, iter, sym)
5713 if (!SYMBOL_IS_ARGUMENT (sym))
5720 insert_exception_resume_breakpoint (ecs->event_thread,
5729 stop_waiting (struct execution_control_state *ecs)
5732 fprintf_unfiltered (gdb_stdlog, "infrun: stop_waiting\n");
5734 clear_step_over_info ();
5736 /* Let callers know we don't want to wait for the inferior anymore. */
5737 ecs->wait_some_more = 0;
5740 /* Called when we should continue running the inferior, because the
5741 current event doesn't cause a user visible stop. This does the
5742 resuming part; waiting for the next event is done elsewhere. */
5745 keep_going (struct execution_control_state *ecs)
5747 /* Make sure normal_stop is called if we get a QUIT handled before
5749 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
5751 /* Save the pc before execution, to compare with pc after stop. */
5752 ecs->event_thread->prev_pc
5753 = regcache_read_pc (get_thread_regcache (ecs->ptid));
5755 if (ecs->event_thread->control.trap_expected
5756 && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_TRAP)
5758 /* We haven't yet gotten our trap, and either: intercepted a
5759 non-signal event (e.g., a fork); or took a signal which we
5760 are supposed to pass through to the inferior. Simply
5762 discard_cleanups (old_cleanups);
5763 resume (currently_stepping (ecs->event_thread),
5764 ecs->event_thread->suspend.stop_signal);
5768 volatile struct gdb_exception e;
5769 struct regcache *regcache = get_current_regcache ();
5771 /* Either the trap was not expected, but we are continuing
5772 anyway (if we got a signal, the user asked it be passed to
5775 We got our expected trap, but decided we should resume from
5778 We're going to run this baby now!
5780 Note that insert_breakpoints won't try to re-insert
5781 already inserted breakpoints. Therefore, we don't
5782 care if breakpoints were already inserted, or not. */
5784 /* If we need to step over a breakpoint, and we're not using
5785 displaced stepping to do so, insert all breakpoints
5786 (watchpoints, etc.) but the one we're stepping over, step one
5787 instruction, and then re-insert the breakpoint when that step
5789 if ((ecs->hit_singlestep_breakpoint
5790 || thread_still_needs_step_over (ecs->event_thread))
5791 && !use_displaced_stepping (get_regcache_arch (regcache)))
5793 set_step_over_info (get_regcache_aspace (regcache),
5794 regcache_read_pc (regcache));
5797 clear_step_over_info ();
5799 /* Stop stepping if inserting breakpoints fails. */
5800 TRY_CATCH (e, RETURN_MASK_ERROR)
5802 insert_breakpoints ();
5806 exception_print (gdb_stderr, e);
5811 ecs->event_thread->control.trap_expected
5812 = (ecs->event_thread->stepping_over_breakpoint
5813 || ecs->hit_singlestep_breakpoint);
5815 /* Do not deliver GDB_SIGNAL_TRAP (except when the user
5816 explicitly specifies that such a signal should be delivered
5817 to the target program). Typically, that would occur when a
5818 user is debugging a target monitor on a simulator: the target
5819 monitor sets a breakpoint; the simulator encounters this
5820 breakpoint and halts the simulation handing control to GDB;
5821 GDB, noting that the stop address doesn't map to any known
5822 breakpoint, returns control back to the simulator; the
5823 simulator then delivers the hardware equivalent of a
5824 GDB_SIGNAL_TRAP to the program being debugged. */
5825 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5826 && !signal_program[ecs->event_thread->suspend.stop_signal])
5827 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5829 discard_cleanups (old_cleanups);
5830 resume (currently_stepping (ecs->event_thread),
5831 ecs->event_thread->suspend.stop_signal);
5834 prepare_to_wait (ecs);
5837 /* This function normally comes after a resume, before
5838 handle_inferior_event exits. It takes care of any last bits of
5839 housekeeping, and sets the all-important wait_some_more flag. */
5842 prepare_to_wait (struct execution_control_state *ecs)
5845 fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n");
5847 /* This is the old end of the while loop. Let everybody know we
5848 want to wait for the inferior some more and get called again
5850 ecs->wait_some_more = 1;
5853 /* We are done with the step range of a step/next/si/ni command.
5854 Called once for each n of a "step n" operation. Notify observers
5855 if not in the middle of doing a "step N" operation for N > 1. */
5858 end_stepping_range (struct execution_control_state *ecs)
5860 ecs->event_thread->control.stop_step = 1;
5861 if (!ecs->event_thread->step_multi)
5862 observer_notify_end_stepping_range ();
5866 /* Several print_*_reason functions to print why the inferior has stopped.
5867 We always print something when the inferior exits, or receives a signal.
5868 The rest of the cases are dealt with later on in normal_stop and
5869 print_it_typical. Ideally there should be a call to one of these
5870 print_*_reason functions functions from handle_inferior_event each time
5871 stop_waiting is called.
5873 Note that we don't call these directly, instead we delegate that to
5874 the interpreters, through observers. Interpreters then call these
5875 with whatever uiout is right. */
5878 print_end_stepping_range_reason (struct ui_out *uiout)
5880 /* For CLI-like interpreters, print nothing. */
5882 if (ui_out_is_mi_like_p (uiout))
5884 ui_out_field_string (uiout, "reason",
5885 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE));
5890 print_signal_exited_reason (struct ui_out *uiout, enum gdb_signal siggnal)
5892 annotate_signalled ();
5893 if (ui_out_is_mi_like_p (uiout))
5895 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED));
5896 ui_out_text (uiout, "\nProgram terminated with signal ");
5897 annotate_signal_name ();
5898 ui_out_field_string (uiout, "signal-name",
5899 gdb_signal_to_name (siggnal));
5900 annotate_signal_name_end ();
5901 ui_out_text (uiout, ", ");
5902 annotate_signal_string ();
5903 ui_out_field_string (uiout, "signal-meaning",
5904 gdb_signal_to_string (siggnal));
5905 annotate_signal_string_end ();
5906 ui_out_text (uiout, ".\n");
5907 ui_out_text (uiout, "The program no longer exists.\n");
5911 print_exited_reason (struct ui_out *uiout, int exitstatus)
5913 struct inferior *inf = current_inferior ();
5914 const char *pidstr = target_pid_to_str (pid_to_ptid (inf->pid));
5916 annotate_exited (exitstatus);
5919 if (ui_out_is_mi_like_p (uiout))
5920 ui_out_field_string (uiout, "reason",
5921 async_reason_lookup (EXEC_ASYNC_EXITED));
5922 ui_out_text (uiout, "[Inferior ");
5923 ui_out_text (uiout, plongest (inf->num));
5924 ui_out_text (uiout, " (");
5925 ui_out_text (uiout, pidstr);
5926 ui_out_text (uiout, ") exited with code ");
5927 ui_out_field_fmt (uiout, "exit-code", "0%o", (unsigned int) exitstatus);
5928 ui_out_text (uiout, "]\n");
5932 if (ui_out_is_mi_like_p (uiout))
5934 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY));
5935 ui_out_text (uiout, "[Inferior ");
5936 ui_out_text (uiout, plongest (inf->num));
5937 ui_out_text (uiout, " (");
5938 ui_out_text (uiout, pidstr);
5939 ui_out_text (uiout, ") exited normally]\n");
5944 print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal)
5948 if (siggnal == GDB_SIGNAL_0 && !ui_out_is_mi_like_p (uiout))
5950 struct thread_info *t = inferior_thread ();
5952 ui_out_text (uiout, "\n[");
5953 ui_out_field_string (uiout, "thread-name",
5954 target_pid_to_str (t->ptid));
5955 ui_out_field_fmt (uiout, "thread-id", "] #%d", t->num);
5956 ui_out_text (uiout, " stopped");
5960 ui_out_text (uiout, "\nProgram received signal ");
5961 annotate_signal_name ();
5962 if (ui_out_is_mi_like_p (uiout))
5964 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
5965 ui_out_field_string (uiout, "signal-name",
5966 gdb_signal_to_name (siggnal));
5967 annotate_signal_name_end ();
5968 ui_out_text (uiout, ", ");
5969 annotate_signal_string ();
5970 ui_out_field_string (uiout, "signal-meaning",
5971 gdb_signal_to_string (siggnal));
5972 annotate_signal_string_end ();
5974 ui_out_text (uiout, ".\n");
5978 print_no_history_reason (struct ui_out *uiout)
5980 ui_out_text (uiout, "\nNo more reverse-execution history.\n");
5983 /* Print current location without a level number, if we have changed
5984 functions or hit a breakpoint. Print source line if we have one.
5985 bpstat_print contains the logic deciding in detail what to print,
5986 based on the event(s) that just occurred. */
5989 print_stop_event (struct target_waitstatus *ws)
5993 int do_frame_printing = 1;
5994 struct thread_info *tp = inferior_thread ();
5996 bpstat_ret = bpstat_print (tp->control.stop_bpstat, ws->kind);
6000 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
6001 should) carry around the function and does (or should) use
6002 that when doing a frame comparison. */
6003 if (tp->control.stop_step
6004 && frame_id_eq (tp->control.step_frame_id,
6005 get_frame_id (get_current_frame ()))
6006 && step_start_function == find_pc_function (stop_pc))
6008 /* Finished step, just print source line. */
6009 source_flag = SRC_LINE;
6013 /* Print location and source line. */
6014 source_flag = SRC_AND_LOC;
6017 case PRINT_SRC_AND_LOC:
6018 /* Print location and source line. */
6019 source_flag = SRC_AND_LOC;
6021 case PRINT_SRC_ONLY:
6022 source_flag = SRC_LINE;
6025 /* Something bogus. */
6026 source_flag = SRC_LINE;
6027 do_frame_printing = 0;
6030 internal_error (__FILE__, __LINE__, _("Unknown value."));
6033 /* The behavior of this routine with respect to the source
6035 SRC_LINE: Print only source line
6036 LOCATION: Print only location
6037 SRC_AND_LOC: Print location and source line. */
6038 if (do_frame_printing)
6039 print_stack_frame (get_selected_frame (NULL), 0, source_flag, 1);
6041 /* Display the auto-display expressions. */
6045 /* Here to return control to GDB when the inferior stops for real.
6046 Print appropriate messages, remove breakpoints, give terminal our modes.
6048 STOP_PRINT_FRAME nonzero means print the executing frame
6049 (pc, function, args, file, line number and line text).
6050 BREAKPOINTS_FAILED nonzero means stop was due to error
6051 attempting to insert breakpoints. */
6056 struct target_waitstatus last;
6058 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
6060 get_last_target_status (&last_ptid, &last);
6062 /* If an exception is thrown from this point on, make sure to
6063 propagate GDB's knowledge of the executing state to the
6064 frontend/user running state. A QUIT is an easy exception to see
6065 here, so do this before any filtered output. */
6067 make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
6068 else if (last.kind != TARGET_WAITKIND_SIGNALLED
6069 && last.kind != TARGET_WAITKIND_EXITED
6070 && last.kind != TARGET_WAITKIND_NO_RESUMED)
6071 make_cleanup (finish_thread_state_cleanup, &inferior_ptid);
6073 /* As with the notification of thread events, we want to delay
6074 notifying the user that we've switched thread context until
6075 the inferior actually stops.
6077 There's no point in saying anything if the inferior has exited.
6078 Note that SIGNALLED here means "exited with a signal", not
6079 "received a signal".
6081 Also skip saying anything in non-stop mode. In that mode, as we
6082 don't want GDB to switch threads behind the user's back, to avoid
6083 races where the user is typing a command to apply to thread x,
6084 but GDB switches to thread y before the user finishes entering
6085 the command, fetch_inferior_event installs a cleanup to restore
6086 the current thread back to the thread the user had selected right
6087 after this event is handled, so we're not really switching, only
6088 informing of a stop. */
6090 && !ptid_equal (previous_inferior_ptid, inferior_ptid)
6091 && target_has_execution
6092 && last.kind != TARGET_WAITKIND_SIGNALLED
6093 && last.kind != TARGET_WAITKIND_EXITED
6094 && last.kind != TARGET_WAITKIND_NO_RESUMED)
6096 target_terminal_ours_for_output ();
6097 printf_filtered (_("[Switching to %s]\n"),
6098 target_pid_to_str (inferior_ptid));
6099 annotate_thread_changed ();
6100 previous_inferior_ptid = inferior_ptid;
6103 if (last.kind == TARGET_WAITKIND_NO_RESUMED)
6105 gdb_assert (sync_execution || !target_can_async_p ());
6107 target_terminal_ours_for_output ();
6108 printf_filtered (_("No unwaited-for children left.\n"));
6111 if (!breakpoints_should_be_inserted_now () && target_has_execution)
6113 if (remove_breakpoints ())
6115 target_terminal_ours_for_output ();
6116 printf_filtered (_("Cannot remove breakpoints because "
6117 "program is no longer writable.\nFurther "
6118 "execution is probably impossible.\n"));
6122 /* If an auto-display called a function and that got a signal,
6123 delete that auto-display to avoid an infinite recursion. */
6125 if (stopped_by_random_signal)
6126 disable_current_display ();
6128 /* Don't print a message if in the middle of doing a "step n"
6129 operation for n > 1 */
6130 if (target_has_execution
6131 && last.kind != TARGET_WAITKIND_SIGNALLED
6132 && last.kind != TARGET_WAITKIND_EXITED
6133 && inferior_thread ()->step_multi
6134 && inferior_thread ()->control.stop_step)
6137 target_terminal_ours ();
6138 async_enable_stdin ();
6140 /* Set the current source location. This will also happen if we
6141 display the frame below, but the current SAL will be incorrect
6142 during a user hook-stop function. */
6143 if (has_stack_frames () && !stop_stack_dummy)
6144 set_current_sal_from_frame (get_current_frame ());
6146 /* Let the user/frontend see the threads as stopped, but do nothing
6147 if the thread was running an infcall. We may be e.g., evaluating
6148 a breakpoint condition. In that case, the thread had state
6149 THREAD_RUNNING before the infcall, and shall remain set to
6150 running, all without informing the user/frontend about state
6151 transition changes. If this is actually a call command, then the
6152 thread was originally already stopped, so there's no state to
6154 if (target_has_execution && inferior_thread ()->control.in_infcall)
6155 discard_cleanups (old_chain);
6157 do_cleanups (old_chain);
6159 /* Look up the hook_stop and run it (CLI internally handles problem
6160 of stop_command's pre-hook not existing). */
6162 catch_errors (hook_stop_stub, stop_command,
6163 "Error while running hook_stop:\n", RETURN_MASK_ALL);
6165 if (!has_stack_frames ())
6168 if (last.kind == TARGET_WAITKIND_SIGNALLED
6169 || last.kind == TARGET_WAITKIND_EXITED)
6172 /* Select innermost stack frame - i.e., current frame is frame 0,
6173 and current location is based on that.
6174 Don't do this on return from a stack dummy routine,
6175 or if the program has exited. */
6177 if (!stop_stack_dummy)
6179 select_frame (get_current_frame ());
6181 /* If --batch-silent is enabled then there's no need to print the current
6182 source location, and to try risks causing an error message about
6183 missing source files. */
6184 if (stop_print_frame && !batch_silent)
6185 print_stop_event (&last);
6188 /* Save the function value return registers, if we care.
6189 We might be about to restore their previous contents. */
6190 if (inferior_thread ()->control.proceed_to_finish
6191 && execution_direction != EXEC_REVERSE)
6193 /* This should not be necessary. */
6195 regcache_xfree (stop_registers);
6197 /* NB: The copy goes through to the target picking up the value of
6198 all the registers. */
6199 stop_registers = regcache_dup (get_current_regcache ());
6202 if (stop_stack_dummy == STOP_STACK_DUMMY)
6204 /* Pop the empty frame that contains the stack dummy.
6205 This also restores inferior state prior to the call
6206 (struct infcall_suspend_state). */
6207 struct frame_info *frame = get_current_frame ();
6209 gdb_assert (get_frame_type (frame) == DUMMY_FRAME);
6211 /* frame_pop() calls reinit_frame_cache as the last thing it
6212 does which means there's currently no selected frame. We
6213 don't need to re-establish a selected frame if the dummy call
6214 returns normally, that will be done by
6215 restore_infcall_control_state. However, we do have to handle
6216 the case where the dummy call is returning after being
6217 stopped (e.g. the dummy call previously hit a breakpoint).
6218 We can't know which case we have so just always re-establish
6219 a selected frame here. */
6220 select_frame (get_current_frame ());
6224 annotate_stopped ();
6226 /* Suppress the stop observer if we're in the middle of:
6228 - a step n (n > 1), as there still more steps to be done.
6230 - a "finish" command, as the observer will be called in
6231 finish_command_continuation, so it can include the inferior
6232 function's return value.
6234 - calling an inferior function, as we pretend we inferior didn't
6235 run at all. The return value of the call is handled by the
6236 expression evaluator, through call_function_by_hand. */
6238 if (!target_has_execution
6239 || last.kind == TARGET_WAITKIND_SIGNALLED
6240 || last.kind == TARGET_WAITKIND_EXITED
6241 || last.kind == TARGET_WAITKIND_NO_RESUMED
6242 || (!(inferior_thread ()->step_multi
6243 && inferior_thread ()->control.stop_step)
6244 && !(inferior_thread ()->control.stop_bpstat
6245 && inferior_thread ()->control.proceed_to_finish)
6246 && !inferior_thread ()->control.in_infcall))
6248 if (!ptid_equal (inferior_ptid, null_ptid))
6249 observer_notify_normal_stop (inferior_thread ()->control.stop_bpstat,
6252 observer_notify_normal_stop (NULL, stop_print_frame);
6255 if (target_has_execution)
6257 if (last.kind != TARGET_WAITKIND_SIGNALLED
6258 && last.kind != TARGET_WAITKIND_EXITED)
6259 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6260 Delete any breakpoint that is to be deleted at the next stop. */
6261 breakpoint_auto_delete (inferior_thread ()->control.stop_bpstat);
6264 /* Try to get rid of automatically added inferiors that are no
6265 longer needed. Keeping those around slows down things linearly.
6266 Note that this never removes the current inferior. */
6271 hook_stop_stub (void *cmd)
6273 execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
6278 signal_stop_state (int signo)
6280 return signal_stop[signo];
6284 signal_print_state (int signo)
6286 return signal_print[signo];
6290 signal_pass_state (int signo)
6292 return signal_program[signo];
6296 signal_cache_update (int signo)
6300 for (signo = 0; signo < (int) GDB_SIGNAL_LAST; signo++)
6301 signal_cache_update (signo);
6306 signal_pass[signo] = (signal_stop[signo] == 0
6307 && signal_print[signo] == 0
6308 && signal_program[signo] == 1
6309 && signal_catch[signo] == 0);
6313 signal_stop_update (int signo, int state)
6315 int ret = signal_stop[signo];
6317 signal_stop[signo] = state;
6318 signal_cache_update (signo);
6323 signal_print_update (int signo, int state)
6325 int ret = signal_print[signo];
6327 signal_print[signo] = state;
6328 signal_cache_update (signo);
6333 signal_pass_update (int signo, int state)
6335 int ret = signal_program[signo];
6337 signal_program[signo] = state;
6338 signal_cache_update (signo);
6342 /* Update the global 'signal_catch' from INFO and notify the
6346 signal_catch_update (const unsigned int *info)
6350 for (i = 0; i < GDB_SIGNAL_LAST; ++i)
6351 signal_catch[i] = info[i] > 0;
6352 signal_cache_update (-1);
6353 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
6357 sig_print_header (void)
6359 printf_filtered (_("Signal Stop\tPrint\tPass "
6360 "to program\tDescription\n"));
6364 sig_print_info (enum gdb_signal oursig)
6366 const char *name = gdb_signal_to_name (oursig);
6367 int name_padding = 13 - strlen (name);
6369 if (name_padding <= 0)
6372 printf_filtered ("%s", name);
6373 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
6374 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
6375 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
6376 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
6377 printf_filtered ("%s\n", gdb_signal_to_string (oursig));
6380 /* Specify how various signals in the inferior should be handled. */
6383 handle_command (char *args, int from_tty)
6386 int digits, wordlen;
6387 int sigfirst, signum, siglast;
6388 enum gdb_signal oursig;
6391 unsigned char *sigs;
6392 struct cleanup *old_chain;
6396 error_no_arg (_("signal to handle"));
6399 /* Allocate and zero an array of flags for which signals to handle. */
6401 nsigs = (int) GDB_SIGNAL_LAST;
6402 sigs = (unsigned char *) alloca (nsigs);
6403 memset (sigs, 0, nsigs);
6405 /* Break the command line up into args. */
6407 argv = gdb_buildargv (args);
6408 old_chain = make_cleanup_freeargv (argv);
6410 /* Walk through the args, looking for signal oursigs, signal names, and
6411 actions. Signal numbers and signal names may be interspersed with
6412 actions, with the actions being performed for all signals cumulatively
6413 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6415 while (*argv != NULL)
6417 wordlen = strlen (*argv);
6418 for (digits = 0; isdigit ((*argv)[digits]); digits++)
6422 sigfirst = siglast = -1;
6424 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
6426 /* Apply action to all signals except those used by the
6427 debugger. Silently skip those. */
6430 siglast = nsigs - 1;
6432 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
6434 SET_SIGS (nsigs, sigs, signal_stop);
6435 SET_SIGS (nsigs, sigs, signal_print);
6437 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
6439 UNSET_SIGS (nsigs, sigs, signal_program);
6441 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
6443 SET_SIGS (nsigs, sigs, signal_print);
6445 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
6447 SET_SIGS (nsigs, sigs, signal_program);
6449 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
6451 UNSET_SIGS (nsigs, sigs, signal_stop);
6453 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
6455 SET_SIGS (nsigs, sigs, signal_program);
6457 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
6459 UNSET_SIGS (nsigs, sigs, signal_print);
6460 UNSET_SIGS (nsigs, sigs, signal_stop);
6462 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
6464 UNSET_SIGS (nsigs, sigs, signal_program);
6466 else if (digits > 0)
6468 /* It is numeric. The numeric signal refers to our own
6469 internal signal numbering from target.h, not to host/target
6470 signal number. This is a feature; users really should be
6471 using symbolic names anyway, and the common ones like
6472 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6474 sigfirst = siglast = (int)
6475 gdb_signal_from_command (atoi (*argv));
6476 if ((*argv)[digits] == '-')
6479 gdb_signal_from_command (atoi ((*argv) + digits + 1));
6481 if (sigfirst > siglast)
6483 /* Bet he didn't figure we'd think of this case... */
6491 oursig = gdb_signal_from_name (*argv);
6492 if (oursig != GDB_SIGNAL_UNKNOWN)
6494 sigfirst = siglast = (int) oursig;
6498 /* Not a number and not a recognized flag word => complain. */
6499 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv);
6503 /* If any signal numbers or symbol names were found, set flags for
6504 which signals to apply actions to. */
6506 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
6508 switch ((enum gdb_signal) signum)
6510 case GDB_SIGNAL_TRAP:
6511 case GDB_SIGNAL_INT:
6512 if (!allsigs && !sigs[signum])
6514 if (query (_("%s is used by the debugger.\n\
6515 Are you sure you want to change it? "),
6516 gdb_signal_to_name ((enum gdb_signal) signum)))
6522 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6523 gdb_flush (gdb_stdout);
6528 case GDB_SIGNAL_DEFAULT:
6529 case GDB_SIGNAL_UNKNOWN:
6530 /* Make sure that "all" doesn't print these. */
6541 for (signum = 0; signum < nsigs; signum++)
6544 signal_cache_update (-1);
6545 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
6546 target_program_signals ((int) GDB_SIGNAL_LAST, signal_program);
6550 /* Show the results. */
6551 sig_print_header ();
6552 for (; signum < nsigs; signum++)
6554 sig_print_info (signum);
6560 do_cleanups (old_chain);
6563 /* Complete the "handle" command. */
6565 static VEC (char_ptr) *
6566 handle_completer (struct cmd_list_element *ignore,
6567 const char *text, const char *word)
6569 VEC (char_ptr) *vec_signals, *vec_keywords, *return_val;
6570 static const char * const keywords[] =
6584 vec_signals = signal_completer (ignore, text, word);
6585 vec_keywords = complete_on_enum (keywords, word, word);
6587 return_val = VEC_merge (char_ptr, vec_signals, vec_keywords);
6588 VEC_free (char_ptr, vec_signals);
6589 VEC_free (char_ptr, vec_keywords);
6594 xdb_handle_command (char *args, int from_tty)
6597 struct cleanup *old_chain;
6600 error_no_arg (_("xdb command"));
6602 /* Break the command line up into args. */
6604 argv = gdb_buildargv (args);
6605 old_chain = make_cleanup_freeargv (argv);
6606 if (argv[1] != (char *) NULL)
6611 bufLen = strlen (argv[0]) + 20;
6612 argBuf = (char *) xmalloc (bufLen);
6616 enum gdb_signal oursig;
6618 oursig = gdb_signal_from_name (argv[0]);
6619 memset (argBuf, 0, bufLen);
6620 if (strcmp (argv[1], "Q") == 0)
6621 sprintf (argBuf, "%s %s", argv[0], "noprint");
6624 if (strcmp (argv[1], "s") == 0)
6626 if (!signal_stop[oursig])
6627 sprintf (argBuf, "%s %s", argv[0], "stop");
6629 sprintf (argBuf, "%s %s", argv[0], "nostop");
6631 else if (strcmp (argv[1], "i") == 0)
6633 if (!signal_program[oursig])
6634 sprintf (argBuf, "%s %s", argv[0], "pass");
6636 sprintf (argBuf, "%s %s", argv[0], "nopass");
6638 else if (strcmp (argv[1], "r") == 0)
6640 if (!signal_print[oursig])
6641 sprintf (argBuf, "%s %s", argv[0], "print");
6643 sprintf (argBuf, "%s %s", argv[0], "noprint");
6649 handle_command (argBuf, from_tty);
6651 printf_filtered (_("Invalid signal handling flag.\n"));
6656 do_cleanups (old_chain);
6660 gdb_signal_from_command (int num)
6662 if (num >= 1 && num <= 15)
6663 return (enum gdb_signal) num;
6664 error (_("Only signals 1-15 are valid as numeric signals.\n\
6665 Use \"info signals\" for a list of symbolic signals."));
6668 /* Print current contents of the tables set by the handle command.
6669 It is possible we should just be printing signals actually used
6670 by the current target (but for things to work right when switching
6671 targets, all signals should be in the signal tables). */
6674 signals_info (char *signum_exp, int from_tty)
6676 enum gdb_signal oursig;
6678 sig_print_header ();
6682 /* First see if this is a symbol name. */
6683 oursig = gdb_signal_from_name (signum_exp);
6684 if (oursig == GDB_SIGNAL_UNKNOWN)
6686 /* No, try numeric. */
6688 gdb_signal_from_command (parse_and_eval_long (signum_exp));
6690 sig_print_info (oursig);
6694 printf_filtered ("\n");
6695 /* These ugly casts brought to you by the native VAX compiler. */
6696 for (oursig = GDB_SIGNAL_FIRST;
6697 (int) oursig < (int) GDB_SIGNAL_LAST;
6698 oursig = (enum gdb_signal) ((int) oursig + 1))
6702 if (oursig != GDB_SIGNAL_UNKNOWN
6703 && oursig != GDB_SIGNAL_DEFAULT && oursig != GDB_SIGNAL_0)
6704 sig_print_info (oursig);
6707 printf_filtered (_("\nUse the \"handle\" command "
6708 "to change these tables.\n"));
6711 /* Check if it makes sense to read $_siginfo from the current thread
6712 at this point. If not, throw an error. */
6715 validate_siginfo_access (void)
6717 /* No current inferior, no siginfo. */
6718 if (ptid_equal (inferior_ptid, null_ptid))
6719 error (_("No thread selected."));
6721 /* Don't try to read from a dead thread. */
6722 if (is_exited (inferior_ptid))
6723 error (_("The current thread has terminated"));
6725 /* ... or from a spinning thread. */
6726 if (is_running (inferior_ptid))
6727 error (_("Selected thread is running."));
6730 /* The $_siginfo convenience variable is a bit special. We don't know
6731 for sure the type of the value until we actually have a chance to
6732 fetch the data. The type can change depending on gdbarch, so it is
6733 also dependent on which thread you have selected.
6735 1. making $_siginfo be an internalvar that creates a new value on
6738 2. making the value of $_siginfo be an lval_computed value. */
6740 /* This function implements the lval_computed support for reading a
6744 siginfo_value_read (struct value *v)
6746 LONGEST transferred;
6748 validate_siginfo_access ();
6751 target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO,
6753 value_contents_all_raw (v),
6755 TYPE_LENGTH (value_type (v)));
6757 if (transferred != TYPE_LENGTH (value_type (v)))
6758 error (_("Unable to read siginfo"));
6761 /* This function implements the lval_computed support for writing a
6765 siginfo_value_write (struct value *v, struct value *fromval)
6767 LONGEST transferred;
6769 validate_siginfo_access ();
6771 transferred = target_write (¤t_target,
6772 TARGET_OBJECT_SIGNAL_INFO,
6774 value_contents_all_raw (fromval),
6776 TYPE_LENGTH (value_type (fromval)));
6778 if (transferred != TYPE_LENGTH (value_type (fromval)))
6779 error (_("Unable to write siginfo"));
6782 static const struct lval_funcs siginfo_value_funcs =
6788 /* Return a new value with the correct type for the siginfo object of
6789 the current thread using architecture GDBARCH. Return a void value
6790 if there's no object available. */
6792 static struct value *
6793 siginfo_make_value (struct gdbarch *gdbarch, struct internalvar *var,
6796 if (target_has_stack
6797 && !ptid_equal (inferior_ptid, null_ptid)
6798 && gdbarch_get_siginfo_type_p (gdbarch))
6800 struct type *type = gdbarch_get_siginfo_type (gdbarch);
6802 return allocate_computed_value (type, &siginfo_value_funcs, NULL);
6805 return allocate_value (builtin_type (gdbarch)->builtin_void);
6809 /* infcall_suspend_state contains state about the program itself like its
6810 registers and any signal it received when it last stopped.
6811 This state must be restored regardless of how the inferior function call
6812 ends (either successfully, or after it hits a breakpoint or signal)
6813 if the program is to properly continue where it left off. */
6815 struct infcall_suspend_state
6817 struct thread_suspend_state thread_suspend;
6818 #if 0 /* Currently unused and empty structures are not valid C. */
6819 struct inferior_suspend_state inferior_suspend;
6824 struct regcache *registers;
6826 /* Format of SIGINFO_DATA or NULL if it is not present. */
6827 struct gdbarch *siginfo_gdbarch;
6829 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
6830 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
6831 content would be invalid. */
6832 gdb_byte *siginfo_data;
6835 struct infcall_suspend_state *
6836 save_infcall_suspend_state (void)
6838 struct infcall_suspend_state *inf_state;
6839 struct thread_info *tp = inferior_thread ();
6841 struct inferior *inf = current_inferior ();
6843 struct regcache *regcache = get_current_regcache ();
6844 struct gdbarch *gdbarch = get_regcache_arch (regcache);
6845 gdb_byte *siginfo_data = NULL;
6847 if (gdbarch_get_siginfo_type_p (gdbarch))
6849 struct type *type = gdbarch_get_siginfo_type (gdbarch);
6850 size_t len = TYPE_LENGTH (type);
6851 struct cleanup *back_to;
6853 siginfo_data = xmalloc (len);
6854 back_to = make_cleanup (xfree, siginfo_data);
6856 if (target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
6857 siginfo_data, 0, len) == len)
6858 discard_cleanups (back_to);
6861 /* Errors ignored. */
6862 do_cleanups (back_to);
6863 siginfo_data = NULL;
6867 inf_state = XCNEW (struct infcall_suspend_state);
6871 inf_state->siginfo_gdbarch = gdbarch;
6872 inf_state->siginfo_data = siginfo_data;
6875 inf_state->thread_suspend = tp->suspend;
6876 #if 0 /* Currently unused and empty structures are not valid C. */
6877 inf_state->inferior_suspend = inf->suspend;
6880 /* run_inferior_call will not use the signal due to its `proceed' call with
6881 GDB_SIGNAL_0 anyway. */
6882 tp->suspend.stop_signal = GDB_SIGNAL_0;
6884 inf_state->stop_pc = stop_pc;
6886 inf_state->registers = regcache_dup (regcache);
6891 /* Restore inferior session state to INF_STATE. */
6894 restore_infcall_suspend_state (struct infcall_suspend_state *inf_state)
6896 struct thread_info *tp = inferior_thread ();
6898 struct inferior *inf = current_inferior ();
6900 struct regcache *regcache = get_current_regcache ();
6901 struct gdbarch *gdbarch = get_regcache_arch (regcache);
6903 tp->suspend = inf_state->thread_suspend;
6904 #if 0 /* Currently unused and empty structures are not valid C. */
6905 inf->suspend = inf_state->inferior_suspend;
6908 stop_pc = inf_state->stop_pc;
6910 if (inf_state->siginfo_gdbarch == gdbarch)
6912 struct type *type = gdbarch_get_siginfo_type (gdbarch);
6914 /* Errors ignored. */
6915 target_write (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
6916 inf_state->siginfo_data, 0, TYPE_LENGTH (type));
6919 /* The inferior can be gone if the user types "print exit(0)"
6920 (and perhaps other times). */
6921 if (target_has_execution)
6922 /* NB: The register write goes through to the target. */
6923 regcache_cpy (regcache, inf_state->registers);
6925 discard_infcall_suspend_state (inf_state);
6929 do_restore_infcall_suspend_state_cleanup (void *state)
6931 restore_infcall_suspend_state (state);
6935 make_cleanup_restore_infcall_suspend_state
6936 (struct infcall_suspend_state *inf_state)
6938 return make_cleanup (do_restore_infcall_suspend_state_cleanup, inf_state);
6942 discard_infcall_suspend_state (struct infcall_suspend_state *inf_state)
6944 regcache_xfree (inf_state->registers);
6945 xfree (inf_state->siginfo_data);
6950 get_infcall_suspend_state_regcache (struct infcall_suspend_state *inf_state)
6952 return inf_state->registers;
6955 /* infcall_control_state contains state regarding gdb's control of the
6956 inferior itself like stepping control. It also contains session state like
6957 the user's currently selected frame. */
6959 struct infcall_control_state
6961 struct thread_control_state thread_control;
6962 struct inferior_control_state inferior_control;
6965 enum stop_stack_kind stop_stack_dummy;
6966 int stopped_by_random_signal;
6967 int stop_after_trap;
6969 /* ID if the selected frame when the inferior function call was made. */
6970 struct frame_id selected_frame_id;
6973 /* Save all of the information associated with the inferior<==>gdb
6976 struct infcall_control_state *
6977 save_infcall_control_state (void)
6979 struct infcall_control_state *inf_status = xmalloc (sizeof (*inf_status));
6980 struct thread_info *tp = inferior_thread ();
6981 struct inferior *inf = current_inferior ();
6983 inf_status->thread_control = tp->control;
6984 inf_status->inferior_control = inf->control;
6986 tp->control.step_resume_breakpoint = NULL;
6987 tp->control.exception_resume_breakpoint = NULL;
6989 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
6990 chain. If caller's caller is walking the chain, they'll be happier if we
6991 hand them back the original chain when restore_infcall_control_state is
6993 tp->control.stop_bpstat = bpstat_copy (tp->control.stop_bpstat);
6996 inf_status->stop_stack_dummy = stop_stack_dummy;
6997 inf_status->stopped_by_random_signal = stopped_by_random_signal;
6998 inf_status->stop_after_trap = stop_after_trap;
7000 inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL));
7006 restore_selected_frame (void *args)
7008 struct frame_id *fid = (struct frame_id *) args;
7009 struct frame_info *frame;
7011 frame = frame_find_by_id (*fid);
7013 /* If inf_status->selected_frame_id is NULL, there was no previously
7017 warning (_("Unable to restore previously selected frame."));
7021 select_frame (frame);
7026 /* Restore inferior session state to INF_STATUS. */
7029 restore_infcall_control_state (struct infcall_control_state *inf_status)
7031 struct thread_info *tp = inferior_thread ();
7032 struct inferior *inf = current_inferior ();
7034 if (tp->control.step_resume_breakpoint)
7035 tp->control.step_resume_breakpoint->disposition = disp_del_at_next_stop;
7037 if (tp->control.exception_resume_breakpoint)
7038 tp->control.exception_resume_breakpoint->disposition
7039 = disp_del_at_next_stop;
7041 /* Handle the bpstat_copy of the chain. */
7042 bpstat_clear (&tp->control.stop_bpstat);
7044 tp->control = inf_status->thread_control;
7045 inf->control = inf_status->inferior_control;
7048 stop_stack_dummy = inf_status->stop_stack_dummy;
7049 stopped_by_random_signal = inf_status->stopped_by_random_signal;
7050 stop_after_trap = inf_status->stop_after_trap;
7052 if (target_has_stack)
7054 /* The point of catch_errors is that if the stack is clobbered,
7055 walking the stack might encounter a garbage pointer and
7056 error() trying to dereference it. */
7058 (restore_selected_frame, &inf_status->selected_frame_id,
7059 "Unable to restore previously selected frame:\n",
7060 RETURN_MASK_ERROR) == 0)
7061 /* Error in restoring the selected frame. Select the innermost
7063 select_frame (get_current_frame ());
7070 do_restore_infcall_control_state_cleanup (void *sts)
7072 restore_infcall_control_state (sts);
7076 make_cleanup_restore_infcall_control_state
7077 (struct infcall_control_state *inf_status)
7079 return make_cleanup (do_restore_infcall_control_state_cleanup, inf_status);
7083 discard_infcall_control_state (struct infcall_control_state *inf_status)
7085 if (inf_status->thread_control.step_resume_breakpoint)
7086 inf_status->thread_control.step_resume_breakpoint->disposition
7087 = disp_del_at_next_stop;
7089 if (inf_status->thread_control.exception_resume_breakpoint)
7090 inf_status->thread_control.exception_resume_breakpoint->disposition
7091 = disp_del_at_next_stop;
7093 /* See save_infcall_control_state for info on stop_bpstat. */
7094 bpstat_clear (&inf_status->thread_control.stop_bpstat);
7099 /* restore_inferior_ptid() will be used by the cleanup machinery
7100 to restore the inferior_ptid value saved in a call to
7101 save_inferior_ptid(). */
7104 restore_inferior_ptid (void *arg)
7106 ptid_t *saved_ptid_ptr = arg;
7108 inferior_ptid = *saved_ptid_ptr;
7112 /* Save the value of inferior_ptid so that it may be restored by a
7113 later call to do_cleanups(). Returns the struct cleanup pointer
7114 needed for later doing the cleanup. */
7117 save_inferior_ptid (void)
7119 ptid_t *saved_ptid_ptr;
7121 saved_ptid_ptr = xmalloc (sizeof (ptid_t));
7122 *saved_ptid_ptr = inferior_ptid;
7123 return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
7129 clear_exit_convenience_vars (void)
7131 clear_internalvar (lookup_internalvar ("_exitsignal"));
7132 clear_internalvar (lookup_internalvar ("_exitcode"));
7136 /* User interface for reverse debugging:
7137 Set exec-direction / show exec-direction commands
7138 (returns error unless target implements to_set_exec_direction method). */
7140 int execution_direction = EXEC_FORWARD;
7141 static const char exec_forward[] = "forward";
7142 static const char exec_reverse[] = "reverse";
7143 static const char *exec_direction = exec_forward;
7144 static const char *const exec_direction_names[] = {
7151 set_exec_direction_func (char *args, int from_tty,
7152 struct cmd_list_element *cmd)
7154 if (target_can_execute_reverse)
7156 if (!strcmp (exec_direction, exec_forward))
7157 execution_direction = EXEC_FORWARD;
7158 else if (!strcmp (exec_direction, exec_reverse))
7159 execution_direction = EXEC_REVERSE;
7163 exec_direction = exec_forward;
7164 error (_("Target does not support this operation."));
7169 show_exec_direction_func (struct ui_file *out, int from_tty,
7170 struct cmd_list_element *cmd, const char *value)
7172 switch (execution_direction) {
7174 fprintf_filtered (out, _("Forward.\n"));
7177 fprintf_filtered (out, _("Reverse.\n"));
7180 internal_error (__FILE__, __LINE__,
7181 _("bogus execution_direction value: %d"),
7182 (int) execution_direction);
7187 show_schedule_multiple (struct ui_file *file, int from_tty,
7188 struct cmd_list_element *c, const char *value)
7190 fprintf_filtered (file, _("Resuming the execution of threads "
7191 "of all processes is %s.\n"), value);
7194 /* Implementation of `siginfo' variable. */
7196 static const struct internalvar_funcs siginfo_funcs =
7204 _initialize_infrun (void)
7208 struct cmd_list_element *c;
7210 add_info ("signals", signals_info, _("\
7211 What debugger does when program gets various signals.\n\
7212 Specify a signal as argument to print info on that signal only."));
7213 add_info_alias ("handle", "signals", 0);
7215 c = add_com ("handle", class_run, handle_command, _("\
7216 Specify how to handle signals.\n\
7217 Usage: handle SIGNAL [ACTIONS]\n\
7218 Args are signals and actions to apply to those signals.\n\
7219 If no actions are specified, the current settings for the specified signals\n\
7220 will be displayed instead.\n\
7222 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7223 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7224 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7225 The special arg \"all\" is recognized to mean all signals except those\n\
7226 used by the debugger, typically SIGTRAP and SIGINT.\n\
7228 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7229 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7230 Stop means reenter debugger if this signal happens (implies print).\n\
7231 Print means print a message if this signal happens.\n\
7232 Pass means let program see this signal; otherwise program doesn't know.\n\
7233 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7234 Pass and Stop may be combined.\n\
7236 Multiple signals may be specified. Signal numbers and signal names\n\
7237 may be interspersed with actions, with the actions being performed for\n\
7238 all signals cumulatively specified."));
7239 set_cmd_completer (c, handle_completer);
7243 add_com ("lz", class_info, signals_info, _("\
7244 What debugger does when program gets various signals.\n\
7245 Specify a signal as argument to print info on that signal only."));
7246 add_com ("z", class_run, xdb_handle_command, _("\
7247 Specify how to handle a signal.\n\
7248 Args are signals and actions to apply to those signals.\n\
7249 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7250 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7251 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7252 The special arg \"all\" is recognized to mean all signals except those\n\
7253 used by the debugger, typically SIGTRAP and SIGINT.\n\
7254 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7255 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7256 nopass), \"Q\" (noprint)\n\
7257 Stop means reenter debugger if this signal happens (implies print).\n\
7258 Print means print a message if this signal happens.\n\
7259 Pass means let program see this signal; otherwise program doesn't know.\n\
7260 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7261 Pass and Stop may be combined."));
7265 stop_command = add_cmd ("stop", class_obscure,
7266 not_just_help_class_command, _("\
7267 There is no `stop' command, but you can set a hook on `stop'.\n\
7268 This allows you to set a list of commands to be run each time execution\n\
7269 of the program stops."), &cmdlist);
7271 add_setshow_zuinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\
7272 Set inferior debugging."), _("\
7273 Show inferior debugging."), _("\
7274 When non-zero, inferior specific debugging is enabled."),
7277 &setdebuglist, &showdebuglist);
7279 add_setshow_boolean_cmd ("displaced", class_maintenance,
7280 &debug_displaced, _("\
7281 Set displaced stepping debugging."), _("\
7282 Show displaced stepping debugging."), _("\
7283 When non-zero, displaced stepping specific debugging is enabled."),
7285 show_debug_displaced,
7286 &setdebuglist, &showdebuglist);
7288 add_setshow_boolean_cmd ("non-stop", no_class,
7290 Set whether gdb controls the inferior in non-stop mode."), _("\
7291 Show whether gdb controls the inferior in non-stop mode."), _("\
7292 When debugging a multi-threaded program and this setting is\n\
7293 off (the default, also called all-stop mode), when one thread stops\n\
7294 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7295 all other threads in the program while you interact with the thread of\n\
7296 interest. When you continue or step a thread, you can allow the other\n\
7297 threads to run, or have them remain stopped, but while you inspect any\n\
7298 thread's state, all threads stop.\n\
7300 In non-stop mode, when one thread stops, other threads can continue\n\
7301 to run freely. You'll be able to step each thread independently,\n\
7302 leave it stopped or free to run as needed."),
7308 numsigs = (int) GDB_SIGNAL_LAST;
7309 signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs);
7310 signal_print = (unsigned char *)
7311 xmalloc (sizeof (signal_print[0]) * numsigs);
7312 signal_program = (unsigned char *)
7313 xmalloc (sizeof (signal_program[0]) * numsigs);
7314 signal_catch = (unsigned char *)
7315 xmalloc (sizeof (signal_catch[0]) * numsigs);
7316 signal_pass = (unsigned char *)
7317 xmalloc (sizeof (signal_pass[0]) * numsigs);
7318 for (i = 0; i < numsigs; i++)
7321 signal_print[i] = 1;
7322 signal_program[i] = 1;
7323 signal_catch[i] = 0;
7326 /* Signals caused by debugger's own actions
7327 should not be given to the program afterwards. */
7328 signal_program[GDB_SIGNAL_TRAP] = 0;
7329 signal_program[GDB_SIGNAL_INT] = 0;
7331 /* Signals that are not errors should not normally enter the debugger. */
7332 signal_stop[GDB_SIGNAL_ALRM] = 0;
7333 signal_print[GDB_SIGNAL_ALRM] = 0;
7334 signal_stop[GDB_SIGNAL_VTALRM] = 0;
7335 signal_print[GDB_SIGNAL_VTALRM] = 0;
7336 signal_stop[GDB_SIGNAL_PROF] = 0;
7337 signal_print[GDB_SIGNAL_PROF] = 0;
7338 signal_stop[GDB_SIGNAL_CHLD] = 0;
7339 signal_print[GDB_SIGNAL_CHLD] = 0;
7340 signal_stop[GDB_SIGNAL_IO] = 0;
7341 signal_print[GDB_SIGNAL_IO] = 0;
7342 signal_stop[GDB_SIGNAL_POLL] = 0;
7343 signal_print[GDB_SIGNAL_POLL] = 0;
7344 signal_stop[GDB_SIGNAL_URG] = 0;
7345 signal_print[GDB_SIGNAL_URG] = 0;
7346 signal_stop[GDB_SIGNAL_WINCH] = 0;
7347 signal_print[GDB_SIGNAL_WINCH] = 0;
7348 signal_stop[GDB_SIGNAL_PRIO] = 0;
7349 signal_print[GDB_SIGNAL_PRIO] = 0;
7351 /* These signals are used internally by user-level thread
7352 implementations. (See signal(5) on Solaris.) Like the above
7353 signals, a healthy program receives and handles them as part of
7354 its normal operation. */
7355 signal_stop[GDB_SIGNAL_LWP] = 0;
7356 signal_print[GDB_SIGNAL_LWP] = 0;
7357 signal_stop[GDB_SIGNAL_WAITING] = 0;
7358 signal_print[GDB_SIGNAL_WAITING] = 0;
7359 signal_stop[GDB_SIGNAL_CANCEL] = 0;
7360 signal_print[GDB_SIGNAL_CANCEL] = 0;
7362 /* Update cached state. */
7363 signal_cache_update (-1);
7365 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support,
7366 &stop_on_solib_events, _("\
7367 Set stopping for shared library events."), _("\
7368 Show stopping for shared library events."), _("\
7369 If nonzero, gdb will give control to the user when the dynamic linker\n\
7370 notifies gdb of shared library events. The most common event of interest\n\
7371 to the user would be loading/unloading of a new library."),
7372 set_stop_on_solib_events,
7373 show_stop_on_solib_events,
7374 &setlist, &showlist);
7376 add_setshow_enum_cmd ("follow-fork-mode", class_run,
7377 follow_fork_mode_kind_names,
7378 &follow_fork_mode_string, _("\
7379 Set debugger response to a program call of fork or vfork."), _("\
7380 Show debugger response to a program call of fork or vfork."), _("\
7381 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7382 parent - the original process is debugged after a fork\n\
7383 child - the new process is debugged after a fork\n\
7384 The unfollowed process will continue to run.\n\
7385 By default, the debugger will follow the parent process."),
7387 show_follow_fork_mode_string,
7388 &setlist, &showlist);
7390 add_setshow_enum_cmd ("follow-exec-mode", class_run,
7391 follow_exec_mode_names,
7392 &follow_exec_mode_string, _("\
7393 Set debugger response to a program call of exec."), _("\
7394 Show debugger response to a program call of exec."), _("\
7395 An exec call replaces the program image of a process.\n\
7397 follow-exec-mode can be:\n\
7399 new - the debugger creates a new inferior and rebinds the process\n\
7400 to this new inferior. The program the process was running before\n\
7401 the exec call can be restarted afterwards by restarting the original\n\
7404 same - the debugger keeps the process bound to the same inferior.\n\
7405 The new executable image replaces the previous executable loaded in\n\
7406 the inferior. Restarting the inferior after the exec call restarts\n\
7407 the executable the process was running after the exec call.\n\
7409 By default, the debugger will use the same inferior."),
7411 show_follow_exec_mode_string,
7412 &setlist, &showlist);
7414 add_setshow_enum_cmd ("scheduler-locking", class_run,
7415 scheduler_enums, &scheduler_mode, _("\
7416 Set mode for locking scheduler during execution."), _("\
7417 Show mode for locking scheduler during execution."), _("\
7418 off == no locking (threads may preempt at any time)\n\
7419 on == full locking (no thread except the current thread may run)\n\
7420 step == scheduler locked during every single-step operation.\n\
7421 In this mode, no other thread may run during a step command.\n\
7422 Other threads may run while stepping over a function call ('next')."),
7423 set_schedlock_func, /* traps on target vector */
7424 show_scheduler_mode,
7425 &setlist, &showlist);
7427 add_setshow_boolean_cmd ("schedule-multiple", class_run, &sched_multi, _("\
7428 Set mode for resuming threads of all processes."), _("\
7429 Show mode for resuming threads of all processes."), _("\
7430 When on, execution commands (such as 'continue' or 'next') resume all\n\
7431 threads of all processes. When off (which is the default), execution\n\
7432 commands only resume the threads of the current process. The set of\n\
7433 threads that are resumed is further refined by the scheduler-locking\n\
7434 mode (see help set scheduler-locking)."),
7436 show_schedule_multiple,
7437 &setlist, &showlist);
7439 add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\
7440 Set mode of the step operation."), _("\
7441 Show mode of the step operation."), _("\
7442 When set, doing a step over a function without debug line information\n\
7443 will stop at the first instruction of that function. Otherwise, the\n\
7444 function is skipped and the step command stops at a different source line."),
7446 show_step_stop_if_no_debug,
7447 &setlist, &showlist);
7449 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run,
7450 &can_use_displaced_stepping, _("\
7451 Set debugger's willingness to use displaced stepping."), _("\
7452 Show debugger's willingness to use displaced stepping."), _("\
7453 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7454 supported by the target architecture. If off, gdb will not use displaced\n\
7455 stepping to step over breakpoints, even if such is supported by the target\n\
7456 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7457 if the target architecture supports it and non-stop mode is active, but will not\n\
7458 use it in all-stop mode (see help set non-stop)."),
7460 show_can_use_displaced_stepping,
7461 &setlist, &showlist);
7463 add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names,
7464 &exec_direction, _("Set direction of execution.\n\
7465 Options are 'forward' or 'reverse'."),
7466 _("Show direction of execution (forward/reverse)."),
7467 _("Tells gdb whether to execute forward or backward."),
7468 set_exec_direction_func, show_exec_direction_func,
7469 &setlist, &showlist);
7471 /* Set/show detach-on-fork: user-settable mode. */
7473 add_setshow_boolean_cmd ("detach-on-fork", class_run, &detach_fork, _("\
7474 Set whether gdb will detach the child of a fork."), _("\
7475 Show whether gdb will detach the child of a fork."), _("\
7476 Tells gdb whether to detach the child of a fork."),
7477 NULL, NULL, &setlist, &showlist);
7479 /* Set/show disable address space randomization mode. */
7481 add_setshow_boolean_cmd ("disable-randomization", class_support,
7482 &disable_randomization, _("\
7483 Set disabling of debuggee's virtual address space randomization."), _("\
7484 Show disabling of debuggee's virtual address space randomization."), _("\
7485 When this mode is on (which is the default), randomization of the virtual\n\
7486 address space is disabled. Standalone programs run with the randomization\n\
7487 enabled by default on some platforms."),
7488 &set_disable_randomization,
7489 &show_disable_randomization,
7490 &setlist, &showlist);
7492 /* ptid initializations */
7493 inferior_ptid = null_ptid;
7494 target_last_wait_ptid = minus_one_ptid;
7496 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed);
7497 observer_attach_thread_stop_requested (infrun_thread_stop_requested);
7498 observer_attach_thread_exit (infrun_thread_thread_exit);
7499 observer_attach_inferior_exit (infrun_inferior_exit);
7501 /* Explicitly create without lookup, since that tries to create a
7502 value with a void typed value, and when we get here, gdbarch
7503 isn't initialized yet. At this point, we're quite sure there
7504 isn't another convenience variable of the same name. */
7505 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs, NULL);
7507 add_setshow_boolean_cmd ("observer", no_class,
7508 &observer_mode_1, _("\
7509 Set whether gdb controls the inferior in observer mode."), _("\
7510 Show whether gdb controls the inferior in observer mode."), _("\
7511 In observer mode, GDB can get data from the inferior, but not\n\
7512 affect its execution. Registers and memory may not be changed,\n\
7513 breakpoints may not be set, and the program cannot be interrupted\n\