1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2013 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/>. */
22 #include "gdb_string.h"
27 #include "exceptions.h"
28 #include "breakpoint.h"
32 #include "cli/cli-script.h"
34 #include "gdbthread.h"
46 #include "dictionary.h"
48 #include "gdb_assert.h"
49 #include "mi/mi-common.h"
50 #include "event-top.h"
52 #include "record-full.h"
53 #include "inline-frame.h"
55 #include "tracepoint.h"
56 #include "continuations.h"
61 #include "completer.h"
62 #include "target-descriptions.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 int currently_stepping_or_nexting_callback (struct thread_info *tp,
90 static void xdb_handle_command (char *args, int from_tty);
92 static int prepare_to_proceed (int);
94 static void print_exited_reason (int exitstatus);
96 static void print_signal_exited_reason (enum gdb_signal siggnal);
98 static void print_no_history_reason (void);
100 static void print_signal_received_reason (enum gdb_signal siggnal);
102 static void print_end_stepping_range_reason (void);
104 void _initialize_infrun (void);
106 void nullify_last_target_wait_ptid (void);
108 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info *);
110 static void insert_step_resume_breakpoint_at_caller (struct frame_info *);
112 static void insert_longjmp_resume_breakpoint (struct gdbarch *, CORE_ADDR);
114 /* When set, stop the 'step' command if we enter a function which has
115 no line number information. The normal behavior is that we step
116 over such function. */
117 int step_stop_if_no_debug = 0;
119 show_step_stop_if_no_debug (struct ui_file *file, int from_tty,
120 struct cmd_list_element *c, const char *value)
122 fprintf_filtered (file, _("Mode of the step operation is %s.\n"), value);
125 /* In asynchronous mode, but simulating synchronous execution. */
127 int sync_execution = 0;
129 /* wait_for_inferior and normal_stop use this to notify the user
130 when the inferior stopped in a different thread than it had been
133 static ptid_t previous_inferior_ptid;
135 /* Default behavior is to detach newly forked processes (legacy). */
138 int debug_displaced = 0;
140 show_debug_displaced (struct ui_file *file, int from_tty,
141 struct cmd_list_element *c, const char *value)
143 fprintf_filtered (file, _("Displace stepping debugging is %s.\n"), value);
146 unsigned int debug_infrun = 0;
148 show_debug_infrun (struct ui_file *file, int from_tty,
149 struct cmd_list_element *c, const char *value)
151 fprintf_filtered (file, _("Inferior debugging is %s.\n"), value);
155 /* Support for disabling address space randomization. */
157 int disable_randomization = 1;
160 show_disable_randomization (struct ui_file *file, int from_tty,
161 struct cmd_list_element *c, const char *value)
163 if (target_supports_disable_randomization ())
164 fprintf_filtered (file,
165 _("Disabling randomization of debuggee's "
166 "virtual address space is %s.\n"),
169 fputs_filtered (_("Disabling randomization of debuggee's "
170 "virtual address space is unsupported on\n"
171 "this platform.\n"), file);
175 set_disable_randomization (char *args, int from_tty,
176 struct cmd_list_element *c)
178 if (!target_supports_disable_randomization ())
179 error (_("Disabling randomization of debuggee's "
180 "virtual address space is unsupported on\n"
184 /* User interface for non-stop mode. */
187 static int non_stop_1 = 0;
190 set_non_stop (char *args, int from_tty,
191 struct cmd_list_element *c)
193 if (target_has_execution)
195 non_stop_1 = non_stop;
196 error (_("Cannot change this setting while the inferior is running."));
199 non_stop = non_stop_1;
203 show_non_stop (struct ui_file *file, int from_tty,
204 struct cmd_list_element *c, const char *value)
206 fprintf_filtered (file,
207 _("Controlling the inferior in non-stop mode is %s.\n"),
211 /* "Observer mode" is somewhat like a more extreme version of
212 non-stop, in which all GDB operations that might affect the
213 target's execution have been disabled. */
215 int observer_mode = 0;
216 static int observer_mode_1 = 0;
219 set_observer_mode (char *args, int from_tty,
220 struct cmd_list_element *c)
222 extern int pagination_enabled;
224 if (target_has_execution)
226 observer_mode_1 = observer_mode;
227 error (_("Cannot change this setting while the inferior is running."));
230 observer_mode = observer_mode_1;
232 may_write_registers = !observer_mode;
233 may_write_memory = !observer_mode;
234 may_insert_breakpoints = !observer_mode;
235 may_insert_tracepoints = !observer_mode;
236 /* We can insert fast tracepoints in or out of observer mode,
237 but enable them if we're going into this mode. */
239 may_insert_fast_tracepoints = 1;
240 may_stop = !observer_mode;
241 update_target_permissions ();
243 /* Going *into* observer mode we must force non-stop, then
244 going out we leave it that way. */
247 target_async_permitted = 1;
248 pagination_enabled = 0;
249 non_stop = non_stop_1 = 1;
253 printf_filtered (_("Observer mode is now %s.\n"),
254 (observer_mode ? "on" : "off"));
258 show_observer_mode (struct ui_file *file, int from_tty,
259 struct cmd_list_element *c, const char *value)
261 fprintf_filtered (file, _("Observer mode is %s.\n"), value);
264 /* This updates the value of observer mode based on changes in
265 permissions. Note that we are deliberately ignoring the values of
266 may-write-registers and may-write-memory, since the user may have
267 reason to enable these during a session, for instance to turn on a
268 debugging-related global. */
271 update_observer_mode (void)
275 newval = (!may_insert_breakpoints
276 && !may_insert_tracepoints
277 && may_insert_fast_tracepoints
281 /* Let the user know if things change. */
282 if (newval != observer_mode)
283 printf_filtered (_("Observer mode is now %s.\n"),
284 (newval ? "on" : "off"));
286 observer_mode = observer_mode_1 = newval;
289 /* Tables of how to react to signals; the user sets them. */
291 static unsigned char *signal_stop;
292 static unsigned char *signal_print;
293 static unsigned char *signal_program;
295 /* Table of signals that are registered with "catch signal". A
296 non-zero entry indicates that the signal is caught by some "catch
297 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
299 static unsigned char *signal_catch;
301 /* Table of signals that the target may silently handle.
302 This is automatically determined from the flags above,
303 and simply cached here. */
304 static unsigned char *signal_pass;
306 #define SET_SIGS(nsigs,sigs,flags) \
308 int signum = (nsigs); \
309 while (signum-- > 0) \
310 if ((sigs)[signum]) \
311 (flags)[signum] = 1; \
314 #define UNSET_SIGS(nsigs,sigs,flags) \
316 int signum = (nsigs); \
317 while (signum-- > 0) \
318 if ((sigs)[signum]) \
319 (flags)[signum] = 0; \
322 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
323 this function is to avoid exporting `signal_program'. */
326 update_signals_program_target (void)
328 target_program_signals ((int) GDB_SIGNAL_LAST, signal_program);
331 /* Value to pass to target_resume() to cause all threads to resume. */
333 #define RESUME_ALL minus_one_ptid
335 /* Command list pointer for the "stop" placeholder. */
337 static struct cmd_list_element *stop_command;
339 /* Function inferior was in as of last step command. */
341 static struct symbol *step_start_function;
343 /* Nonzero if we want to give control to the user when we're notified
344 of shared library events by the dynamic linker. */
345 int stop_on_solib_events;
347 /* Enable or disable optional shared library event breakpoints
348 as appropriate when the above flag is changed. */
351 set_stop_on_solib_events (char *args, int from_tty, struct cmd_list_element *c)
353 update_solib_breakpoints ();
357 show_stop_on_solib_events (struct ui_file *file, int from_tty,
358 struct cmd_list_element *c, const char *value)
360 fprintf_filtered (file, _("Stopping for shared library events is %s.\n"),
364 /* Nonzero means expecting a trace trap
365 and should stop the inferior and return silently when it happens. */
369 /* Save register contents here when executing a "finish" command or are
370 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
371 Thus this contains the return value from the called function (assuming
372 values are returned in a register). */
374 struct regcache *stop_registers;
376 /* Nonzero after stop if current stack frame should be printed. */
378 static int stop_print_frame;
380 /* This is a cached copy of the pid/waitstatus of the last event
381 returned by target_wait()/deprecated_target_wait_hook(). This
382 information is returned by get_last_target_status(). */
383 static ptid_t target_last_wait_ptid;
384 static struct target_waitstatus target_last_waitstatus;
386 static void context_switch (ptid_t ptid);
388 void init_thread_stepping_state (struct thread_info *tss);
390 static void init_infwait_state (void);
392 static const char follow_fork_mode_child[] = "child";
393 static const char follow_fork_mode_parent[] = "parent";
395 static const char *const follow_fork_mode_kind_names[] = {
396 follow_fork_mode_child,
397 follow_fork_mode_parent,
401 static const char *follow_fork_mode_string = follow_fork_mode_parent;
403 show_follow_fork_mode_string (struct ui_file *file, int from_tty,
404 struct cmd_list_element *c, const char *value)
406 fprintf_filtered (file,
407 _("Debugger response to a program "
408 "call of fork or vfork is \"%s\".\n"),
413 /* Tell the target to follow the fork we're stopped at. Returns true
414 if the inferior should be resumed; false, if the target for some
415 reason decided it's best not to resume. */
420 int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
421 int should_resume = 1;
422 struct thread_info *tp;
424 /* Copy user stepping state to the new inferior thread. FIXME: the
425 followed fork child thread should have a copy of most of the
426 parent thread structure's run control related fields, not just these.
427 Initialized to avoid "may be used uninitialized" warnings from gcc. */
428 struct breakpoint *step_resume_breakpoint = NULL;
429 struct breakpoint *exception_resume_breakpoint = NULL;
430 CORE_ADDR step_range_start = 0;
431 CORE_ADDR step_range_end = 0;
432 struct frame_id step_frame_id = { 0 };
437 struct target_waitstatus wait_status;
439 /* Get the last target status returned by target_wait(). */
440 get_last_target_status (&wait_ptid, &wait_status);
442 /* If not stopped at a fork event, then there's nothing else to
444 if (wait_status.kind != TARGET_WAITKIND_FORKED
445 && wait_status.kind != TARGET_WAITKIND_VFORKED)
448 /* Check if we switched over from WAIT_PTID, since the event was
450 if (!ptid_equal (wait_ptid, minus_one_ptid)
451 && !ptid_equal (inferior_ptid, wait_ptid))
453 /* We did. Switch back to WAIT_PTID thread, to tell the
454 target to follow it (in either direction). We'll
455 afterwards refuse to resume, and inform the user what
457 switch_to_thread (wait_ptid);
462 tp = inferior_thread ();
464 /* If there were any forks/vforks that were caught and are now to be
465 followed, then do so now. */
466 switch (tp->pending_follow.kind)
468 case TARGET_WAITKIND_FORKED:
469 case TARGET_WAITKIND_VFORKED:
471 ptid_t parent, child;
473 /* If the user did a next/step, etc, over a fork call,
474 preserve the stepping state in the fork child. */
475 if (follow_child && should_resume)
477 step_resume_breakpoint = clone_momentary_breakpoint
478 (tp->control.step_resume_breakpoint);
479 step_range_start = tp->control.step_range_start;
480 step_range_end = tp->control.step_range_end;
481 step_frame_id = tp->control.step_frame_id;
482 exception_resume_breakpoint
483 = clone_momentary_breakpoint (tp->control.exception_resume_breakpoint);
485 /* For now, delete the parent's sr breakpoint, otherwise,
486 parent/child sr breakpoints are considered duplicates,
487 and the child version will not be installed. Remove
488 this when the breakpoints module becomes aware of
489 inferiors and address spaces. */
490 delete_step_resume_breakpoint (tp);
491 tp->control.step_range_start = 0;
492 tp->control.step_range_end = 0;
493 tp->control.step_frame_id = null_frame_id;
494 delete_exception_resume_breakpoint (tp);
497 parent = inferior_ptid;
498 child = tp->pending_follow.value.related_pid;
500 /* Tell the target to do whatever is necessary to follow
501 either parent or child. */
502 if (target_follow_fork (follow_child))
504 /* Target refused to follow, or there's some other reason
505 we shouldn't resume. */
510 /* This pending follow fork event is now handled, one way
511 or another. The previous selected thread may be gone
512 from the lists by now, but if it is still around, need
513 to clear the pending follow request. */
514 tp = find_thread_ptid (parent);
516 tp->pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
518 /* This makes sure we don't try to apply the "Switched
519 over from WAIT_PID" logic above. */
520 nullify_last_target_wait_ptid ();
522 /* If we followed the child, switch to it... */
525 switch_to_thread (child);
527 /* ... and preserve the stepping state, in case the
528 user was stepping over the fork call. */
531 tp = inferior_thread ();
532 tp->control.step_resume_breakpoint
533 = step_resume_breakpoint;
534 tp->control.step_range_start = step_range_start;
535 tp->control.step_range_end = step_range_end;
536 tp->control.step_frame_id = step_frame_id;
537 tp->control.exception_resume_breakpoint
538 = exception_resume_breakpoint;
542 /* If we get here, it was because we're trying to
543 resume from a fork catchpoint, but, the user
544 has switched threads away from the thread that
545 forked. In that case, the resume command
546 issued is most likely not applicable to the
547 child, so just warn, and refuse to resume. */
548 warning (_("Not resuming: switched threads "
549 "before following fork child.\n"));
552 /* Reset breakpoints in the child as appropriate. */
553 follow_inferior_reset_breakpoints ();
556 switch_to_thread (parent);
560 case TARGET_WAITKIND_SPURIOUS:
561 /* Nothing to follow. */
564 internal_error (__FILE__, __LINE__,
565 "Unexpected pending_follow.kind %d\n",
566 tp->pending_follow.kind);
570 return should_resume;
574 follow_inferior_reset_breakpoints (void)
576 struct thread_info *tp = inferior_thread ();
578 /* Was there a step_resume breakpoint? (There was if the user
579 did a "next" at the fork() call.) If so, explicitly reset its
582 step_resumes are a form of bp that are made to be per-thread.
583 Since we created the step_resume bp when the parent process
584 was being debugged, and now are switching to the child process,
585 from the breakpoint package's viewpoint, that's a switch of
586 "threads". We must update the bp's notion of which thread
587 it is for, or it'll be ignored when it triggers. */
589 if (tp->control.step_resume_breakpoint)
590 breakpoint_re_set_thread (tp->control.step_resume_breakpoint);
592 if (tp->control.exception_resume_breakpoint)
593 breakpoint_re_set_thread (tp->control.exception_resume_breakpoint);
595 /* Reinsert all breakpoints in the child. The user may have set
596 breakpoints after catching the fork, in which case those
597 were never set in the child, but only in the parent. This makes
598 sure the inserted breakpoints match the breakpoint list. */
600 breakpoint_re_set ();
601 insert_breakpoints ();
604 /* The child has exited or execed: resume threads of the parent the
605 user wanted to be executing. */
608 proceed_after_vfork_done (struct thread_info *thread,
611 int pid = * (int *) arg;
613 if (ptid_get_pid (thread->ptid) == pid
614 && is_running (thread->ptid)
615 && !is_executing (thread->ptid)
616 && !thread->stop_requested
617 && thread->suspend.stop_signal == GDB_SIGNAL_0)
620 fprintf_unfiltered (gdb_stdlog,
621 "infrun: resuming vfork parent thread %s\n",
622 target_pid_to_str (thread->ptid));
624 switch_to_thread (thread->ptid);
625 clear_proceed_status ();
626 proceed ((CORE_ADDR) -1, GDB_SIGNAL_DEFAULT, 0);
632 /* Called whenever we notice an exec or exit event, to handle
633 detaching or resuming a vfork parent. */
636 handle_vfork_child_exec_or_exit (int exec)
638 struct inferior *inf = current_inferior ();
640 if (inf->vfork_parent)
642 int resume_parent = -1;
644 /* This exec or exit marks the end of the shared memory region
645 between the parent and the child. If the user wanted to
646 detach from the parent, now is the time. */
648 if (inf->vfork_parent->pending_detach)
650 struct thread_info *tp;
651 struct cleanup *old_chain;
652 struct program_space *pspace;
653 struct address_space *aspace;
655 /* follow-fork child, detach-on-fork on. */
657 inf->vfork_parent->pending_detach = 0;
661 /* If we're handling a child exit, then inferior_ptid
662 points at the inferior's pid, not to a thread. */
663 old_chain = save_inferior_ptid ();
664 save_current_program_space ();
665 save_current_inferior ();
668 old_chain = save_current_space_and_thread ();
670 /* We're letting loose of the parent. */
671 tp = any_live_thread_of_process (inf->vfork_parent->pid);
672 switch_to_thread (tp->ptid);
674 /* We're about to detach from the parent, which implicitly
675 removes breakpoints from its address space. There's a
676 catch here: we want to reuse the spaces for the child,
677 but, parent/child are still sharing the pspace at this
678 point, although the exec in reality makes the kernel give
679 the child a fresh set of new pages. The problem here is
680 that the breakpoints module being unaware of this, would
681 likely chose the child process to write to the parent
682 address space. Swapping the child temporarily away from
683 the spaces has the desired effect. Yes, this is "sort
686 pspace = inf->pspace;
687 aspace = inf->aspace;
691 if (debug_infrun || info_verbose)
693 target_terminal_ours ();
696 fprintf_filtered (gdb_stdlog,
697 "Detaching vfork parent process "
698 "%d after child exec.\n",
699 inf->vfork_parent->pid);
701 fprintf_filtered (gdb_stdlog,
702 "Detaching vfork parent process "
703 "%d after child exit.\n",
704 inf->vfork_parent->pid);
707 target_detach (NULL, 0);
710 inf->pspace = pspace;
711 inf->aspace = aspace;
713 do_cleanups (old_chain);
717 /* We're staying attached to the parent, so, really give the
718 child a new address space. */
719 inf->pspace = add_program_space (maybe_new_address_space ());
720 inf->aspace = inf->pspace->aspace;
722 set_current_program_space (inf->pspace);
724 resume_parent = inf->vfork_parent->pid;
726 /* Break the bonds. */
727 inf->vfork_parent->vfork_child = NULL;
731 struct cleanup *old_chain;
732 struct program_space *pspace;
734 /* If this is a vfork child exiting, then the pspace and
735 aspaces were shared with the parent. Since we're
736 reporting the process exit, we'll be mourning all that is
737 found in the address space, and switching to null_ptid,
738 preparing to start a new inferior. But, since we don't
739 want to clobber the parent's address/program spaces, we
740 go ahead and create a new one for this exiting
743 /* Switch to null_ptid, so that clone_program_space doesn't want
744 to read the selected frame of a dead process. */
745 old_chain = save_inferior_ptid ();
746 inferior_ptid = null_ptid;
748 /* This inferior is dead, so avoid giving the breakpoints
749 module the option to write through to it (cloning a
750 program space resets breakpoints). */
753 pspace = add_program_space (maybe_new_address_space ());
754 set_current_program_space (pspace);
756 inf->symfile_flags = SYMFILE_NO_READ;
757 clone_program_space (pspace, inf->vfork_parent->pspace);
758 inf->pspace = pspace;
759 inf->aspace = pspace->aspace;
761 /* Put back inferior_ptid. We'll continue mourning this
763 do_cleanups (old_chain);
765 resume_parent = inf->vfork_parent->pid;
766 /* Break the bonds. */
767 inf->vfork_parent->vfork_child = NULL;
770 inf->vfork_parent = NULL;
772 gdb_assert (current_program_space == inf->pspace);
774 if (non_stop && resume_parent != -1)
776 /* If the user wanted the parent to be running, let it go
778 struct cleanup *old_chain = make_cleanup_restore_current_thread ();
781 fprintf_unfiltered (gdb_stdlog,
782 "infrun: resuming vfork parent process %d\n",
785 iterate_over_threads (proceed_after_vfork_done, &resume_parent);
787 do_cleanups (old_chain);
792 /* Enum strings for "set|show follow-exec-mode". */
794 static const char follow_exec_mode_new[] = "new";
795 static const char follow_exec_mode_same[] = "same";
796 static const char *const follow_exec_mode_names[] =
798 follow_exec_mode_new,
799 follow_exec_mode_same,
803 static const char *follow_exec_mode_string = follow_exec_mode_same;
805 show_follow_exec_mode_string (struct ui_file *file, int from_tty,
806 struct cmd_list_element *c, const char *value)
808 fprintf_filtered (file, _("Follow exec mode is \"%s\".\n"), value);
811 /* EXECD_PATHNAME is assumed to be non-NULL. */
814 follow_exec (ptid_t pid, char *execd_pathname)
816 struct thread_info *th = inferior_thread ();
817 struct inferior *inf = current_inferior ();
819 /* This is an exec event that we actually wish to pay attention to.
820 Refresh our symbol table to the newly exec'd program, remove any
823 If there are breakpoints, they aren't really inserted now,
824 since the exec() transformed our inferior into a fresh set
827 We want to preserve symbolic breakpoints on the list, since
828 we have hopes that they can be reset after the new a.out's
829 symbol table is read.
831 However, any "raw" breakpoints must be removed from the list
832 (e.g., the solib bp's), since their address is probably invalid
835 And, we DON'T want to call delete_breakpoints() here, since
836 that may write the bp's "shadow contents" (the instruction
837 value that was overwritten witha TRAP instruction). Since
838 we now have a new a.out, those shadow contents aren't valid. */
840 mark_breakpoints_out ();
842 update_breakpoints_after_exec ();
844 /* If there was one, it's gone now. We cannot truly step-to-next
845 statement through an exec(). */
846 th->control.step_resume_breakpoint = NULL;
847 th->control.exception_resume_breakpoint = NULL;
848 th->control.step_range_start = 0;
849 th->control.step_range_end = 0;
851 /* The target reports the exec event to the main thread, even if
852 some other thread does the exec, and even if the main thread was
853 already stopped --- if debugging in non-stop mode, it's possible
854 the user had the main thread held stopped in the previous image
855 --- release it now. This is the same behavior as step-over-exec
856 with scheduler-locking on in all-stop mode. */
857 th->stop_requested = 0;
859 /* What is this a.out's name? */
860 printf_unfiltered (_("%s is executing new program: %s\n"),
861 target_pid_to_str (inferior_ptid),
864 /* We've followed the inferior through an exec. Therefore, the
865 inferior has essentially been killed & reborn. */
867 gdb_flush (gdb_stdout);
869 breakpoint_init_inferior (inf_execd);
871 if (gdb_sysroot && *gdb_sysroot)
873 char *name = alloca (strlen (gdb_sysroot)
874 + strlen (execd_pathname)
877 strcpy (name, gdb_sysroot);
878 strcat (name, execd_pathname);
879 execd_pathname = name;
882 /* Reset the shared library package. This ensures that we get a
883 shlib event when the child reaches "_start", at which point the
884 dld will have had a chance to initialize the child. */
885 /* Also, loading a symbol file below may trigger symbol lookups, and
886 we don't want those to be satisfied by the libraries of the
887 previous incarnation of this process. */
888 no_shared_libraries (NULL, 0);
890 if (follow_exec_mode_string == follow_exec_mode_new)
892 struct program_space *pspace;
894 /* The user wants to keep the old inferior and program spaces
895 around. Create a new fresh one, and switch to it. */
897 inf = add_inferior (current_inferior ()->pid);
898 pspace = add_program_space (maybe_new_address_space ());
899 inf->pspace = pspace;
900 inf->aspace = pspace->aspace;
902 exit_inferior_num_silent (current_inferior ()->num);
904 set_current_inferior (inf);
905 set_current_program_space (pspace);
909 /* The old description may no longer be fit for the new image.
910 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
911 old description; we'll read a new one below. No need to do
912 this on "follow-exec-mode new", as the old inferior stays
913 around (its description is later cleared/refetched on
915 target_clear_description ();
918 gdb_assert (current_program_space == inf->pspace);
920 /* That a.out is now the one to use. */
921 exec_file_attach (execd_pathname, 0);
923 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
924 (Position Independent Executable) main symbol file will get applied by
925 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
926 the breakpoints with the zero displacement. */
928 symbol_file_add (execd_pathname,
930 | SYMFILE_MAINLINE | SYMFILE_DEFER_BP_RESET),
933 if ((inf->symfile_flags & SYMFILE_NO_READ) == 0)
934 set_initial_language ();
936 /* If the target can specify a description, read it. Must do this
937 after flipping to the new executable (because the target supplied
938 description must be compatible with the executable's
939 architecture, and the old executable may e.g., be 32-bit, while
940 the new one 64-bit), and before anything involving memory or
942 target_find_description ();
944 solib_create_inferior_hook (0);
946 jit_inferior_created_hook ();
948 breakpoint_re_set ();
950 /* Reinsert all breakpoints. (Those which were symbolic have
951 been reset to the proper address in the new a.out, thanks
952 to symbol_file_command...). */
953 insert_breakpoints ();
955 /* The next resume of this inferior should bring it to the shlib
956 startup breakpoints. (If the user had also set bp's on
957 "main" from the old (parent) process, then they'll auto-
958 matically get reset there in the new process.). */
961 /* Non-zero if we just simulating a single-step. This is needed
962 because we cannot remove the breakpoints in the inferior process
963 until after the `wait' in `wait_for_inferior'. */
964 static int singlestep_breakpoints_inserted_p = 0;
966 /* The thread we inserted single-step breakpoints for. */
967 static ptid_t singlestep_ptid;
969 /* PC when we started this single-step. */
970 static CORE_ADDR singlestep_pc;
972 /* If another thread hit the singlestep breakpoint, we save the original
973 thread here so that we can resume single-stepping it later. */
974 static ptid_t saved_singlestep_ptid;
975 static int stepping_past_singlestep_breakpoint;
977 /* If not equal to null_ptid, this means that after stepping over breakpoint
978 is finished, we need to switch to deferred_step_ptid, and step it.
980 The use case is when one thread has hit a breakpoint, and then the user
981 has switched to another thread and issued 'step'. We need to step over
982 breakpoint in the thread which hit the breakpoint, but then continue
983 stepping the thread user has selected. */
984 static ptid_t deferred_step_ptid;
986 /* Displaced stepping. */
988 /* In non-stop debugging mode, we must take special care to manage
989 breakpoints properly; in particular, the traditional strategy for
990 stepping a thread past a breakpoint it has hit is unsuitable.
991 'Displaced stepping' is a tactic for stepping one thread past a
992 breakpoint it has hit while ensuring that other threads running
993 concurrently will hit the breakpoint as they should.
995 The traditional way to step a thread T off a breakpoint in a
996 multi-threaded program in all-stop mode is as follows:
998 a0) Initially, all threads are stopped, and breakpoints are not
1000 a1) We single-step T, leaving breakpoints uninserted.
1001 a2) We insert breakpoints, and resume all threads.
1003 In non-stop debugging, however, this strategy is unsuitable: we
1004 don't want to have to stop all threads in the system in order to
1005 continue or step T past a breakpoint. Instead, we use displaced
1008 n0) Initially, T is stopped, other threads are running, and
1009 breakpoints are inserted.
1010 n1) We copy the instruction "under" the breakpoint to a separate
1011 location, outside the main code stream, making any adjustments
1012 to the instruction, register, and memory state as directed by
1014 n2) We single-step T over the instruction at its new location.
1015 n3) We adjust the resulting register and memory state as directed
1016 by T's architecture. This includes resetting T's PC to point
1017 back into the main instruction stream.
1020 This approach depends on the following gdbarch methods:
1022 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1023 indicate where to copy the instruction, and how much space must
1024 be reserved there. We use these in step n1.
1026 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1027 address, and makes any necessary adjustments to the instruction,
1028 register contents, and memory. We use this in step n1.
1030 - gdbarch_displaced_step_fixup adjusts registers and memory after
1031 we have successfuly single-stepped the instruction, to yield the
1032 same effect the instruction would have had if we had executed it
1033 at its original address. We use this in step n3.
1035 - gdbarch_displaced_step_free_closure provides cleanup.
1037 The gdbarch_displaced_step_copy_insn and
1038 gdbarch_displaced_step_fixup functions must be written so that
1039 copying an instruction with gdbarch_displaced_step_copy_insn,
1040 single-stepping across the copied instruction, and then applying
1041 gdbarch_displaced_insn_fixup should have the same effects on the
1042 thread's memory and registers as stepping the instruction in place
1043 would have. Exactly which responsibilities fall to the copy and
1044 which fall to the fixup is up to the author of those functions.
1046 See the comments in gdbarch.sh for details.
1048 Note that displaced stepping and software single-step cannot
1049 currently be used in combination, although with some care I think
1050 they could be made to. Software single-step works by placing
1051 breakpoints on all possible subsequent instructions; if the
1052 displaced instruction is a PC-relative jump, those breakpoints
1053 could fall in very strange places --- on pages that aren't
1054 executable, or at addresses that are not proper instruction
1055 boundaries. (We do generally let other threads run while we wait
1056 to hit the software single-step breakpoint, and they might
1057 encounter such a corrupted instruction.) One way to work around
1058 this would be to have gdbarch_displaced_step_copy_insn fully
1059 simulate the effect of PC-relative instructions (and return NULL)
1060 on architectures that use software single-stepping.
1062 In non-stop mode, we can have independent and simultaneous step
1063 requests, so more than one thread may need to simultaneously step
1064 over a breakpoint. The current implementation assumes there is
1065 only one scratch space per process. In this case, we have to
1066 serialize access to the scratch space. If thread A wants to step
1067 over a breakpoint, but we are currently waiting for some other
1068 thread to complete a displaced step, we leave thread A stopped and
1069 place it in the displaced_step_request_queue. Whenever a displaced
1070 step finishes, we pick the next thread in the queue and start a new
1071 displaced step operation on it. See displaced_step_prepare and
1072 displaced_step_fixup for details. */
1074 struct displaced_step_request
1077 struct displaced_step_request *next;
1080 /* Per-inferior displaced stepping state. */
1081 struct displaced_step_inferior_state
1083 /* Pointer to next in linked list. */
1084 struct displaced_step_inferior_state *next;
1086 /* The process this displaced step state refers to. */
1089 /* A queue of pending displaced stepping requests. One entry per
1090 thread that needs to do a displaced step. */
1091 struct displaced_step_request *step_request_queue;
1093 /* If this is not null_ptid, this is the thread carrying out a
1094 displaced single-step in process PID. This thread's state will
1095 require fixing up once it has completed its step. */
1098 /* The architecture the thread had when we stepped it. */
1099 struct gdbarch *step_gdbarch;
1101 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1102 for post-step cleanup. */
1103 struct displaced_step_closure *step_closure;
1105 /* The address of the original instruction, and the copy we
1107 CORE_ADDR step_original, step_copy;
1109 /* Saved contents of copy area. */
1110 gdb_byte *step_saved_copy;
1113 /* The list of states of processes involved in displaced stepping
1115 static struct displaced_step_inferior_state *displaced_step_inferior_states;
1117 /* Get the displaced stepping state of process PID. */
1119 static struct displaced_step_inferior_state *
1120 get_displaced_stepping_state (int pid)
1122 struct displaced_step_inferior_state *state;
1124 for (state = displaced_step_inferior_states;
1126 state = state->next)
1127 if (state->pid == pid)
1133 /* Add a new displaced stepping state for process PID to the displaced
1134 stepping state list, or return a pointer to an already existing
1135 entry, if it already exists. Never returns NULL. */
1137 static struct displaced_step_inferior_state *
1138 add_displaced_stepping_state (int pid)
1140 struct displaced_step_inferior_state *state;
1142 for (state = displaced_step_inferior_states;
1144 state = state->next)
1145 if (state->pid == pid)
1148 state = xcalloc (1, sizeof (*state));
1150 state->next = displaced_step_inferior_states;
1151 displaced_step_inferior_states = state;
1156 /* If inferior is in displaced stepping, and ADDR equals to starting address
1157 of copy area, return corresponding displaced_step_closure. Otherwise,
1160 struct displaced_step_closure*
1161 get_displaced_step_closure_by_addr (CORE_ADDR addr)
1163 struct displaced_step_inferior_state *displaced
1164 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
1166 /* If checking the mode of displaced instruction in copy area. */
1167 if (displaced && !ptid_equal (displaced->step_ptid, null_ptid)
1168 && (displaced->step_copy == addr))
1169 return displaced->step_closure;
1174 /* Remove the displaced stepping state of process PID. */
1177 remove_displaced_stepping_state (int pid)
1179 struct displaced_step_inferior_state *it, **prev_next_p;
1181 gdb_assert (pid != 0);
1183 it = displaced_step_inferior_states;
1184 prev_next_p = &displaced_step_inferior_states;
1189 *prev_next_p = it->next;
1194 prev_next_p = &it->next;
1200 infrun_inferior_exit (struct inferior *inf)
1202 remove_displaced_stepping_state (inf->pid);
1205 /* If ON, and the architecture supports it, GDB will use displaced
1206 stepping to step over breakpoints. If OFF, or if the architecture
1207 doesn't support it, GDB will instead use the traditional
1208 hold-and-step approach. If AUTO (which is the default), GDB will
1209 decide which technique to use to step over breakpoints depending on
1210 which of all-stop or non-stop mode is active --- displaced stepping
1211 in non-stop mode; hold-and-step in all-stop mode. */
1213 static enum auto_boolean can_use_displaced_stepping = AUTO_BOOLEAN_AUTO;
1216 show_can_use_displaced_stepping (struct ui_file *file, int from_tty,
1217 struct cmd_list_element *c,
1220 if (can_use_displaced_stepping == AUTO_BOOLEAN_AUTO)
1221 fprintf_filtered (file,
1222 _("Debugger's willingness to use displaced stepping "
1223 "to step over breakpoints is %s (currently %s).\n"),
1224 value, non_stop ? "on" : "off");
1226 fprintf_filtered (file,
1227 _("Debugger's willingness to use displaced stepping "
1228 "to step over breakpoints is %s.\n"), value);
1231 /* Return non-zero if displaced stepping can/should be used to step
1232 over breakpoints. */
1235 use_displaced_stepping (struct gdbarch *gdbarch)
1237 return (((can_use_displaced_stepping == AUTO_BOOLEAN_AUTO && non_stop)
1238 || can_use_displaced_stepping == AUTO_BOOLEAN_TRUE)
1239 && gdbarch_displaced_step_copy_insn_p (gdbarch)
1240 && !RECORD_IS_USED);
1243 /* Clean out any stray displaced stepping state. */
1245 displaced_step_clear (struct displaced_step_inferior_state *displaced)
1247 /* Indicate that there is no cleanup pending. */
1248 displaced->step_ptid = null_ptid;
1250 if (displaced->step_closure)
1252 gdbarch_displaced_step_free_closure (displaced->step_gdbarch,
1253 displaced->step_closure);
1254 displaced->step_closure = NULL;
1259 displaced_step_clear_cleanup (void *arg)
1261 struct displaced_step_inferior_state *state = arg;
1263 displaced_step_clear (state);
1266 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1268 displaced_step_dump_bytes (struct ui_file *file,
1269 const gdb_byte *buf,
1274 for (i = 0; i < len; i++)
1275 fprintf_unfiltered (file, "%02x ", buf[i]);
1276 fputs_unfiltered ("\n", file);
1279 /* Prepare to single-step, using displaced stepping.
1281 Note that we cannot use displaced stepping when we have a signal to
1282 deliver. If we have a signal to deliver and an instruction to step
1283 over, then after the step, there will be no indication from the
1284 target whether the thread entered a signal handler or ignored the
1285 signal and stepped over the instruction successfully --- both cases
1286 result in a simple SIGTRAP. In the first case we mustn't do a
1287 fixup, and in the second case we must --- but we can't tell which.
1288 Comments in the code for 'random signals' in handle_inferior_event
1289 explain how we handle this case instead.
1291 Returns 1 if preparing was successful -- this thread is going to be
1292 stepped now; or 0 if displaced stepping this thread got queued. */
1294 displaced_step_prepare (ptid_t ptid)
1296 struct cleanup *old_cleanups, *ignore_cleanups;
1297 struct thread_info *tp = find_thread_ptid (ptid);
1298 struct regcache *regcache = get_thread_regcache (ptid);
1299 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1300 CORE_ADDR original, copy;
1302 struct displaced_step_closure *closure;
1303 struct displaced_step_inferior_state *displaced;
1306 /* We should never reach this function if the architecture does not
1307 support displaced stepping. */
1308 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch));
1310 /* Disable range stepping while executing in the scratch pad. We
1311 want a single-step even if executing the displaced instruction in
1312 the scratch buffer lands within the stepping range (e.g., a
1314 tp->control.may_range_step = 0;
1316 /* We have to displaced step one thread at a time, as we only have
1317 access to a single scratch space per inferior. */
1319 displaced = add_displaced_stepping_state (ptid_get_pid (ptid));
1321 if (!ptid_equal (displaced->step_ptid, null_ptid))
1323 /* Already waiting for a displaced step to finish. Defer this
1324 request and place in queue. */
1325 struct displaced_step_request *req, *new_req;
1327 if (debug_displaced)
1328 fprintf_unfiltered (gdb_stdlog,
1329 "displaced: defering step of %s\n",
1330 target_pid_to_str (ptid));
1332 new_req = xmalloc (sizeof (*new_req));
1333 new_req->ptid = ptid;
1334 new_req->next = NULL;
1336 if (displaced->step_request_queue)
1338 for (req = displaced->step_request_queue;
1342 req->next = new_req;
1345 displaced->step_request_queue = new_req;
1351 if (debug_displaced)
1352 fprintf_unfiltered (gdb_stdlog,
1353 "displaced: stepping %s now\n",
1354 target_pid_to_str (ptid));
1357 displaced_step_clear (displaced);
1359 old_cleanups = save_inferior_ptid ();
1360 inferior_ptid = ptid;
1362 original = regcache_read_pc (regcache);
1364 copy = gdbarch_displaced_step_location (gdbarch);
1365 len = gdbarch_max_insn_length (gdbarch);
1367 /* Save the original contents of the copy area. */
1368 displaced->step_saved_copy = xmalloc (len);
1369 ignore_cleanups = make_cleanup (free_current_contents,
1370 &displaced->step_saved_copy);
1371 status = target_read_memory (copy, displaced->step_saved_copy, len);
1373 throw_error (MEMORY_ERROR,
1374 _("Error accessing memory address %s (%s) for "
1375 "displaced-stepping scratch space."),
1376 paddress (gdbarch, copy), safe_strerror (status));
1377 if (debug_displaced)
1379 fprintf_unfiltered (gdb_stdlog, "displaced: saved %s: ",
1380 paddress (gdbarch, copy));
1381 displaced_step_dump_bytes (gdb_stdlog,
1382 displaced->step_saved_copy,
1386 closure = gdbarch_displaced_step_copy_insn (gdbarch,
1387 original, copy, regcache);
1389 /* We don't support the fully-simulated case at present. */
1390 gdb_assert (closure);
1392 /* Save the information we need to fix things up if the step
1394 displaced->step_ptid = ptid;
1395 displaced->step_gdbarch = gdbarch;
1396 displaced->step_closure = closure;
1397 displaced->step_original = original;
1398 displaced->step_copy = copy;
1400 make_cleanup (displaced_step_clear_cleanup, displaced);
1402 /* Resume execution at the copy. */
1403 regcache_write_pc (regcache, copy);
1405 discard_cleanups (ignore_cleanups);
1407 do_cleanups (old_cleanups);
1409 if (debug_displaced)
1410 fprintf_unfiltered (gdb_stdlog, "displaced: displaced pc to %s\n",
1411 paddress (gdbarch, copy));
1417 write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr,
1418 const gdb_byte *myaddr, int len)
1420 struct cleanup *ptid_cleanup = save_inferior_ptid ();
1422 inferior_ptid = ptid;
1423 write_memory (memaddr, myaddr, len);
1424 do_cleanups (ptid_cleanup);
1427 /* Restore the contents of the copy area for thread PTID. */
1430 displaced_step_restore (struct displaced_step_inferior_state *displaced,
1433 ULONGEST len = gdbarch_max_insn_length (displaced->step_gdbarch);
1435 write_memory_ptid (ptid, displaced->step_copy,
1436 displaced->step_saved_copy, len);
1437 if (debug_displaced)
1438 fprintf_unfiltered (gdb_stdlog, "displaced: restored %s %s\n",
1439 target_pid_to_str (ptid),
1440 paddress (displaced->step_gdbarch,
1441 displaced->step_copy));
1445 displaced_step_fixup (ptid_t event_ptid, enum gdb_signal signal)
1447 struct cleanup *old_cleanups;
1448 struct displaced_step_inferior_state *displaced
1449 = get_displaced_stepping_state (ptid_get_pid (event_ptid));
1451 /* Was any thread of this process doing a displaced step? */
1452 if (displaced == NULL)
1455 /* Was this event for the pid we displaced? */
1456 if (ptid_equal (displaced->step_ptid, null_ptid)
1457 || ! ptid_equal (displaced->step_ptid, event_ptid))
1460 old_cleanups = make_cleanup (displaced_step_clear_cleanup, displaced);
1462 displaced_step_restore (displaced, displaced->step_ptid);
1464 /* Did the instruction complete successfully? */
1465 if (signal == GDB_SIGNAL_TRAP)
1467 /* Fix up the resulting state. */
1468 gdbarch_displaced_step_fixup (displaced->step_gdbarch,
1469 displaced->step_closure,
1470 displaced->step_original,
1471 displaced->step_copy,
1472 get_thread_regcache (displaced->step_ptid));
1476 /* Since the instruction didn't complete, all we can do is
1478 struct regcache *regcache = get_thread_regcache (event_ptid);
1479 CORE_ADDR pc = regcache_read_pc (regcache);
1481 pc = displaced->step_original + (pc - displaced->step_copy);
1482 regcache_write_pc (regcache, pc);
1485 do_cleanups (old_cleanups);
1487 displaced->step_ptid = null_ptid;
1489 /* Are there any pending displaced stepping requests? If so, run
1490 one now. Leave the state object around, since we're likely to
1491 need it again soon. */
1492 while (displaced->step_request_queue)
1494 struct displaced_step_request *head;
1496 struct regcache *regcache;
1497 struct gdbarch *gdbarch;
1498 CORE_ADDR actual_pc;
1499 struct address_space *aspace;
1501 head = displaced->step_request_queue;
1503 displaced->step_request_queue = head->next;
1506 context_switch (ptid);
1508 regcache = get_thread_regcache (ptid);
1509 actual_pc = regcache_read_pc (regcache);
1510 aspace = get_regcache_aspace (regcache);
1512 if (breakpoint_here_p (aspace, actual_pc))
1514 if (debug_displaced)
1515 fprintf_unfiltered (gdb_stdlog,
1516 "displaced: stepping queued %s now\n",
1517 target_pid_to_str (ptid));
1519 displaced_step_prepare (ptid);
1521 gdbarch = get_regcache_arch (regcache);
1523 if (debug_displaced)
1525 CORE_ADDR actual_pc = regcache_read_pc (regcache);
1528 fprintf_unfiltered (gdb_stdlog, "displaced: run %s: ",
1529 paddress (gdbarch, actual_pc));
1530 read_memory (actual_pc, buf, sizeof (buf));
1531 displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
1534 if (gdbarch_displaced_step_hw_singlestep (gdbarch,
1535 displaced->step_closure))
1536 target_resume (ptid, 1, GDB_SIGNAL_0);
1538 target_resume (ptid, 0, GDB_SIGNAL_0);
1540 /* Done, we're stepping a thread. */
1546 struct thread_info *tp = inferior_thread ();
1548 /* The breakpoint we were sitting under has since been
1550 tp->control.trap_expected = 0;
1552 /* Go back to what we were trying to do. */
1553 step = currently_stepping (tp);
1555 if (debug_displaced)
1556 fprintf_unfiltered (gdb_stdlog,
1557 "displaced: breakpoint is gone: %s, step(%d)\n",
1558 target_pid_to_str (tp->ptid), step);
1560 target_resume (ptid, step, GDB_SIGNAL_0);
1561 tp->suspend.stop_signal = GDB_SIGNAL_0;
1563 /* This request was discarded. See if there's any other
1564 thread waiting for its turn. */
1569 /* Update global variables holding ptids to hold NEW_PTID if they were
1570 holding OLD_PTID. */
1572 infrun_thread_ptid_changed (ptid_t old_ptid, ptid_t new_ptid)
1574 struct displaced_step_request *it;
1575 struct displaced_step_inferior_state *displaced;
1577 if (ptid_equal (inferior_ptid, old_ptid))
1578 inferior_ptid = new_ptid;
1580 if (ptid_equal (singlestep_ptid, old_ptid))
1581 singlestep_ptid = new_ptid;
1583 if (ptid_equal (deferred_step_ptid, old_ptid))
1584 deferred_step_ptid = new_ptid;
1586 for (displaced = displaced_step_inferior_states;
1588 displaced = displaced->next)
1590 if (ptid_equal (displaced->step_ptid, old_ptid))
1591 displaced->step_ptid = new_ptid;
1593 for (it = displaced->step_request_queue; it; it = it->next)
1594 if (ptid_equal (it->ptid, old_ptid))
1595 it->ptid = new_ptid;
1602 /* Things to clean up if we QUIT out of resume (). */
1604 resume_cleanups (void *ignore)
1609 static const char schedlock_off[] = "off";
1610 static const char schedlock_on[] = "on";
1611 static const char schedlock_step[] = "step";
1612 static const char *const scheduler_enums[] = {
1618 static const char *scheduler_mode = schedlock_off;
1620 show_scheduler_mode (struct ui_file *file, int from_tty,
1621 struct cmd_list_element *c, const char *value)
1623 fprintf_filtered (file,
1624 _("Mode for locking scheduler "
1625 "during execution is \"%s\".\n"),
1630 set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
1632 if (!target_can_lock_scheduler)
1634 scheduler_mode = schedlock_off;
1635 error (_("Target '%s' cannot support this command."), target_shortname);
1639 /* True if execution commands resume all threads of all processes by
1640 default; otherwise, resume only threads of the current inferior
1642 int sched_multi = 0;
1644 /* Try to setup for software single stepping over the specified location.
1645 Return 1 if target_resume() should use hardware single step.
1647 GDBARCH the current gdbarch.
1648 PC the location to step over. */
1651 maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc)
1655 if (execution_direction == EXEC_FORWARD
1656 && gdbarch_software_single_step_p (gdbarch)
1657 && gdbarch_software_single_step (gdbarch, get_current_frame ()))
1660 /* Do not pull these breakpoints until after a `wait' in
1661 `wait_for_inferior'. */
1662 singlestep_breakpoints_inserted_p = 1;
1663 singlestep_ptid = inferior_ptid;
1669 /* Return a ptid representing the set of threads that we will proceed,
1670 in the perspective of the user/frontend. We may actually resume
1671 fewer threads at first, e.g., if a thread is stopped at a
1672 breakpoint that needs stepping-off, but that should not be visible
1673 to the user/frontend, and neither should the frontend/user be
1674 allowed to proceed any of the threads that happen to be stopped for
1675 internal run control handling, if a previous command wanted them
1679 user_visible_resume_ptid (int step)
1681 /* By default, resume all threads of all processes. */
1682 ptid_t resume_ptid = RESUME_ALL;
1684 /* Maybe resume only all threads of the current process. */
1685 if (!sched_multi && target_supports_multi_process ())
1687 resume_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
1690 /* Maybe resume a single thread after all. */
1693 /* With non-stop mode on, threads are always handled
1695 resume_ptid = inferior_ptid;
1697 else if ((scheduler_mode == schedlock_on)
1698 || (scheduler_mode == schedlock_step
1699 && (step || singlestep_breakpoints_inserted_p)))
1701 /* User-settable 'scheduler' mode requires solo thread resume. */
1702 resume_ptid = inferior_ptid;
1708 /* Resume the inferior, but allow a QUIT. This is useful if the user
1709 wants to interrupt some lengthy single-stepping operation
1710 (for child processes, the SIGINT goes to the inferior, and so
1711 we get a SIGINT random_signal, but for remote debugging and perhaps
1712 other targets, that's not true).
1714 STEP nonzero if we should step (zero to continue instead).
1715 SIG is the signal to give the inferior (zero for none). */
1717 resume (int step, enum gdb_signal sig)
1719 int should_resume = 1;
1720 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
1721 struct regcache *regcache = get_current_regcache ();
1722 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1723 struct thread_info *tp = inferior_thread ();
1724 CORE_ADDR pc = regcache_read_pc (regcache);
1725 struct address_space *aspace = get_regcache_aspace (regcache);
1729 if (current_inferior ()->waiting_for_vfork_done)
1731 /* Don't try to single-step a vfork parent that is waiting for
1732 the child to get out of the shared memory region (by exec'ing
1733 or exiting). This is particularly important on software
1734 single-step archs, as the child process would trip on the
1735 software single step breakpoint inserted for the parent
1736 process. Since the parent will not actually execute any
1737 instruction until the child is out of the shared region (such
1738 are vfork's semantics), it is safe to simply continue it.
1739 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
1740 the parent, and tell it to `keep_going', which automatically
1741 re-sets it stepping. */
1743 fprintf_unfiltered (gdb_stdlog,
1744 "infrun: resume : clear step\n");
1749 fprintf_unfiltered (gdb_stdlog,
1750 "infrun: resume (step=%d, signal=%d), "
1751 "trap_expected=%d, current thread [%s] at %s\n",
1752 step, sig, tp->control.trap_expected,
1753 target_pid_to_str (inferior_ptid),
1754 paddress (gdbarch, pc));
1756 /* Normally, by the time we reach `resume', the breakpoints are either
1757 removed or inserted, as appropriate. The exception is if we're sitting
1758 at a permanent breakpoint; we need to step over it, but permanent
1759 breakpoints can't be removed. So we have to test for it here. */
1760 if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here)
1762 if (gdbarch_skip_permanent_breakpoint_p (gdbarch))
1763 gdbarch_skip_permanent_breakpoint (gdbarch, regcache);
1766 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1767 how to step past a permanent breakpoint on this architecture. Try using\n\
1768 a command like `return' or `jump' to continue execution."));
1771 /* If we have a breakpoint to step over, make sure to do a single
1772 step only. Same if we have software watchpoints. */
1773 if (tp->control.trap_expected || bpstat_should_step ())
1774 tp->control.may_range_step = 0;
1776 /* If enabled, step over breakpoints by executing a copy of the
1777 instruction at a different address.
1779 We can't use displaced stepping when we have a signal to deliver;
1780 the comments for displaced_step_prepare explain why. The
1781 comments in the handle_inferior event for dealing with 'random
1782 signals' explain what we do instead.
1784 We can't use displaced stepping when we are waiting for vfork_done
1785 event, displaced stepping breaks the vfork child similarly as single
1786 step software breakpoint. */
1787 if (use_displaced_stepping (gdbarch)
1788 && (tp->control.trap_expected
1789 || (step && gdbarch_software_single_step_p (gdbarch)))
1790 && sig == GDB_SIGNAL_0
1791 && !current_inferior ()->waiting_for_vfork_done)
1793 struct displaced_step_inferior_state *displaced;
1795 if (!displaced_step_prepare (inferior_ptid))
1797 /* Got placed in displaced stepping queue. Will be resumed
1798 later when all the currently queued displaced stepping
1799 requests finish. The thread is not executing at this point,
1800 and the call to set_executing will be made later. But we
1801 need to call set_running here, since from frontend point of view,
1802 the thread is running. */
1803 set_running (inferior_ptid, 1);
1804 discard_cleanups (old_cleanups);
1808 /* Update pc to reflect the new address from which we will execute
1809 instructions due to displaced stepping. */
1810 pc = regcache_read_pc (get_thread_regcache (inferior_ptid));
1812 displaced = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
1813 step = gdbarch_displaced_step_hw_singlestep (gdbarch,
1814 displaced->step_closure);
1817 /* Do we need to do it the hard way, w/temp breakpoints? */
1819 step = maybe_software_singlestep (gdbarch, pc);
1821 /* Currently, our software single-step implementation leads to different
1822 results than hardware single-stepping in one situation: when stepping
1823 into delivering a signal which has an associated signal handler,
1824 hardware single-step will stop at the first instruction of the handler,
1825 while software single-step will simply skip execution of the handler.
1827 For now, this difference in behavior is accepted since there is no
1828 easy way to actually implement single-stepping into a signal handler
1829 without kernel support.
1831 However, there is one scenario where this difference leads to follow-on
1832 problems: if we're stepping off a breakpoint by removing all breakpoints
1833 and then single-stepping. In this case, the software single-step
1834 behavior means that even if there is a *breakpoint* in the signal
1835 handler, GDB still would not stop.
1837 Fortunately, we can at least fix this particular issue. We detect
1838 here the case where we are about to deliver a signal while software
1839 single-stepping with breakpoints removed. In this situation, we
1840 revert the decisions to remove all breakpoints and insert single-
1841 step breakpoints, and instead we install a step-resume breakpoint
1842 at the current address, deliver the signal without stepping, and
1843 once we arrive back at the step-resume breakpoint, actually step
1844 over the breakpoint we originally wanted to step over. */
1845 if (singlestep_breakpoints_inserted_p
1846 && tp->control.trap_expected && sig != GDB_SIGNAL_0)
1848 /* If we have nested signals or a pending signal is delivered
1849 immediately after a handler returns, might might already have
1850 a step-resume breakpoint set on the earlier handler. We cannot
1851 set another step-resume breakpoint; just continue on until the
1852 original breakpoint is hit. */
1853 if (tp->control.step_resume_breakpoint == NULL)
1855 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
1856 tp->step_after_step_resume_breakpoint = 1;
1859 remove_single_step_breakpoints ();
1860 singlestep_breakpoints_inserted_p = 0;
1862 insert_breakpoints ();
1863 tp->control.trap_expected = 0;
1870 /* If STEP is set, it's a request to use hardware stepping
1871 facilities. But in that case, we should never
1872 use singlestep breakpoint. */
1873 gdb_assert (!(singlestep_breakpoints_inserted_p && step));
1875 /* Decide the set of threads to ask the target to resume. Start
1876 by assuming everything will be resumed, than narrow the set
1877 by applying increasingly restricting conditions. */
1878 resume_ptid = user_visible_resume_ptid (step);
1880 /* Maybe resume a single thread after all. */
1881 if (singlestep_breakpoints_inserted_p
1882 && stepping_past_singlestep_breakpoint)
1884 /* The situation here is as follows. In thread T1 we wanted to
1885 single-step. Lacking hardware single-stepping we've
1886 set breakpoint at the PC of the next instruction -- call it
1887 P. After resuming, we've hit that breakpoint in thread T2.
1888 Now we've removed original breakpoint, inserted breakpoint
1889 at P+1, and try to step to advance T2 past breakpoint.
1890 We need to step only T2, as if T1 is allowed to freely run,
1891 it can run past P, and if other threads are allowed to run,
1892 they can hit breakpoint at P+1, and nested hits of single-step
1893 breakpoints is not something we'd want -- that's complicated
1894 to support, and has no value. */
1895 resume_ptid = inferior_ptid;
1897 else if ((step || singlestep_breakpoints_inserted_p)
1898 && tp->control.trap_expected)
1900 /* We're allowing a thread to run past a breakpoint it has
1901 hit, by single-stepping the thread with the breakpoint
1902 removed. In which case, we need to single-step only this
1903 thread, and keep others stopped, as they can miss this
1904 breakpoint if allowed to run.
1906 The current code actually removes all breakpoints when
1907 doing this, not just the one being stepped over, so if we
1908 let other threads run, we can actually miss any
1909 breakpoint, not just the one at PC. */
1910 resume_ptid = inferior_ptid;
1913 if (gdbarch_cannot_step_breakpoint (gdbarch))
1915 /* Most targets can step a breakpoint instruction, thus
1916 executing it normally. But if this one cannot, just
1917 continue and we will hit it anyway. */
1918 if (step && breakpoint_inserted_here_p (aspace, pc))
1923 && use_displaced_stepping (gdbarch)
1924 && tp->control.trap_expected)
1926 struct regcache *resume_regcache = get_thread_regcache (resume_ptid);
1927 struct gdbarch *resume_gdbarch = get_regcache_arch (resume_regcache);
1928 CORE_ADDR actual_pc = regcache_read_pc (resume_regcache);
1931 fprintf_unfiltered (gdb_stdlog, "displaced: run %s: ",
1932 paddress (resume_gdbarch, actual_pc));
1933 read_memory (actual_pc, buf, sizeof (buf));
1934 displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
1937 if (tp->control.may_range_step)
1939 /* If we're resuming a thread with the PC out of the step
1940 range, then we're doing some nested/finer run control
1941 operation, like stepping the thread out of the dynamic
1942 linker or the displaced stepping scratch pad. We
1943 shouldn't have allowed a range step then. */
1944 gdb_assert (pc_in_thread_step_range (pc, tp));
1947 /* Install inferior's terminal modes. */
1948 target_terminal_inferior ();
1950 /* Avoid confusing the next resume, if the next stop/resume
1951 happens to apply to another thread. */
1952 tp->suspend.stop_signal = GDB_SIGNAL_0;
1954 /* Advise target which signals may be handled silently. If we have
1955 removed breakpoints because we are stepping over one (which can
1956 happen only if we are not using displaced stepping), we need to
1957 receive all signals to avoid accidentally skipping a breakpoint
1958 during execution of a signal handler. */
1959 if ((step || singlestep_breakpoints_inserted_p)
1960 && tp->control.trap_expected
1961 && !use_displaced_stepping (gdbarch))
1962 target_pass_signals (0, NULL);
1964 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
1966 target_resume (resume_ptid, step, sig);
1969 discard_cleanups (old_cleanups);
1974 /* Clear out all variables saying what to do when inferior is continued.
1975 First do this, then set the ones you want, then call `proceed'. */
1978 clear_proceed_status_thread (struct thread_info *tp)
1981 fprintf_unfiltered (gdb_stdlog,
1982 "infrun: clear_proceed_status_thread (%s)\n",
1983 target_pid_to_str (tp->ptid));
1985 tp->control.trap_expected = 0;
1986 tp->control.step_range_start = 0;
1987 tp->control.step_range_end = 0;
1988 tp->control.may_range_step = 0;
1989 tp->control.step_frame_id = null_frame_id;
1990 tp->control.step_stack_frame_id = null_frame_id;
1991 tp->control.step_over_calls = STEP_OVER_UNDEBUGGABLE;
1992 tp->stop_requested = 0;
1994 tp->control.stop_step = 0;
1996 tp->control.proceed_to_finish = 0;
1998 /* Discard any remaining commands or status from previous stop. */
1999 bpstat_clear (&tp->control.stop_bpstat);
2003 clear_proceed_status_callback (struct thread_info *tp, void *data)
2005 if (is_exited (tp->ptid))
2008 clear_proceed_status_thread (tp);
2013 clear_proceed_status (void)
2017 /* In all-stop mode, delete the per-thread status of all
2018 threads, even if inferior_ptid is null_ptid, there may be
2019 threads on the list. E.g., we may be launching a new
2020 process, while selecting the executable. */
2021 iterate_over_threads (clear_proceed_status_callback, NULL);
2024 if (!ptid_equal (inferior_ptid, null_ptid))
2026 struct inferior *inferior;
2030 /* If in non-stop mode, only delete the per-thread status of
2031 the current thread. */
2032 clear_proceed_status_thread (inferior_thread ());
2035 inferior = current_inferior ();
2036 inferior->control.stop_soon = NO_STOP_QUIETLY;
2039 stop_after_trap = 0;
2041 observer_notify_about_to_proceed ();
2045 regcache_xfree (stop_registers);
2046 stop_registers = NULL;
2050 /* Check the current thread against the thread that reported the most recent
2051 event. If a step-over is required return TRUE and set the current thread
2052 to the old thread. Otherwise return FALSE.
2054 This should be suitable for any targets that support threads. */
2057 prepare_to_proceed (int step)
2060 struct target_waitstatus wait_status;
2061 int schedlock_enabled;
2063 /* With non-stop mode on, threads are always handled individually. */
2064 gdb_assert (! non_stop);
2066 /* Get the last target status returned by target_wait(). */
2067 get_last_target_status (&wait_ptid, &wait_status);
2069 /* Make sure we were stopped at a breakpoint. */
2070 if (wait_status.kind != TARGET_WAITKIND_STOPPED
2071 || (wait_status.value.sig != GDB_SIGNAL_TRAP
2072 && wait_status.value.sig != GDB_SIGNAL_ILL
2073 && wait_status.value.sig != GDB_SIGNAL_SEGV
2074 && wait_status.value.sig != GDB_SIGNAL_EMT))
2079 schedlock_enabled = (scheduler_mode == schedlock_on
2080 || (scheduler_mode == schedlock_step
2083 /* Don't switch over to WAIT_PTID if scheduler locking is on. */
2084 if (schedlock_enabled)
2087 /* Don't switch over if we're about to resume some other process
2088 other than WAIT_PTID's, and schedule-multiple is off. */
2090 && ptid_get_pid (wait_ptid) != ptid_get_pid (inferior_ptid))
2093 /* Switched over from WAIT_PID. */
2094 if (!ptid_equal (wait_ptid, minus_one_ptid)
2095 && !ptid_equal (inferior_ptid, wait_ptid))
2097 struct regcache *regcache = get_thread_regcache (wait_ptid);
2099 if (breakpoint_here_p (get_regcache_aspace (regcache),
2100 regcache_read_pc (regcache)))
2102 /* If stepping, remember current thread to switch back to. */
2104 deferred_step_ptid = inferior_ptid;
2106 /* Switch back to WAIT_PID thread. */
2107 switch_to_thread (wait_ptid);
2110 fprintf_unfiltered (gdb_stdlog,
2111 "infrun: prepare_to_proceed (step=%d), "
2112 "switched to [%s]\n",
2113 step, target_pid_to_str (inferior_ptid));
2115 /* We return 1 to indicate that there is a breakpoint here,
2116 so we need to step over it before continuing to avoid
2117 hitting it straight away. */
2125 /* Basic routine for continuing the program in various fashions.
2127 ADDR is the address to resume at, or -1 for resume where stopped.
2128 SIGGNAL is the signal to give it, or 0 for none,
2129 or -1 for act according to how it stopped.
2130 STEP is nonzero if should trap after one instruction.
2131 -1 means return after that and print nothing.
2132 You should probably set various step_... variables
2133 before calling here, if you are stepping.
2135 You should call clear_proceed_status before calling proceed. */
2138 proceed (CORE_ADDR addr, enum gdb_signal siggnal, int step)
2140 struct regcache *regcache;
2141 struct gdbarch *gdbarch;
2142 struct thread_info *tp;
2144 struct address_space *aspace;
2145 /* GDB may force the inferior to step due to various reasons. */
2148 /* If we're stopped at a fork/vfork, follow the branch set by the
2149 "set follow-fork-mode" command; otherwise, we'll just proceed
2150 resuming the current thread. */
2151 if (!follow_fork ())
2153 /* The target for some reason decided not to resume. */
2155 if (target_can_async_p ())
2156 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
2160 /* We'll update this if & when we switch to a new thread. */
2161 previous_inferior_ptid = inferior_ptid;
2163 regcache = get_current_regcache ();
2164 gdbarch = get_regcache_arch (regcache);
2165 aspace = get_regcache_aspace (regcache);
2166 pc = regcache_read_pc (regcache);
2169 step_start_function = find_pc_function (pc);
2171 stop_after_trap = 1;
2173 if (addr == (CORE_ADDR) -1)
2175 if (pc == stop_pc && breakpoint_here_p (aspace, pc)
2176 && execution_direction != EXEC_REVERSE)
2177 /* There is a breakpoint at the address we will resume at,
2178 step one instruction before inserting breakpoints so that
2179 we do not stop right away (and report a second hit at this
2182 Note, we don't do this in reverse, because we won't
2183 actually be executing the breakpoint insn anyway.
2184 We'll be (un-)executing the previous instruction. */
2187 else if (gdbarch_single_step_through_delay_p (gdbarch)
2188 && gdbarch_single_step_through_delay (gdbarch,
2189 get_current_frame ()))
2190 /* We stepped onto an instruction that needs to be stepped
2191 again before re-inserting the breakpoint, do so. */
2196 regcache_write_pc (regcache, addr);
2200 fprintf_unfiltered (gdb_stdlog,
2201 "infrun: proceed (addr=%s, signal=%d, step=%d)\n",
2202 paddress (gdbarch, addr), siggnal, step);
2205 /* In non-stop, each thread is handled individually. The context
2206 must already be set to the right thread here. */
2210 /* In a multi-threaded task we may select another thread and
2211 then continue or step.
2213 But if the old thread was stopped at a breakpoint, it will
2214 immediately cause another breakpoint stop without any
2215 execution (i.e. it will report a breakpoint hit incorrectly).
2216 So we must step over it first.
2218 prepare_to_proceed checks the current thread against the
2219 thread that reported the most recent event. If a step-over
2220 is required it returns TRUE and sets the current thread to
2222 if (prepare_to_proceed (step))
2226 /* prepare_to_proceed may change the current thread. */
2227 tp = inferior_thread ();
2231 tp->control.trap_expected = 1;
2232 /* If displaced stepping is enabled, we can step over the
2233 breakpoint without hitting it, so leave all breakpoints
2234 inserted. Otherwise we need to disable all breakpoints, step
2235 one instruction, and then re-add them when that step is
2237 if (!use_displaced_stepping (gdbarch))
2238 remove_breakpoints ();
2241 /* We can insert breakpoints if we're not trying to step over one,
2242 or if we are stepping over one but we're using displaced stepping
2244 if (! tp->control.trap_expected || use_displaced_stepping (gdbarch))
2245 insert_breakpoints ();
2249 /* Pass the last stop signal to the thread we're resuming,
2250 irrespective of whether the current thread is the thread that
2251 got the last event or not. This was historically GDB's
2252 behaviour before keeping a stop_signal per thread. */
2254 struct thread_info *last_thread;
2256 struct target_waitstatus last_status;
2258 get_last_target_status (&last_ptid, &last_status);
2259 if (!ptid_equal (inferior_ptid, last_ptid)
2260 && !ptid_equal (last_ptid, null_ptid)
2261 && !ptid_equal (last_ptid, minus_one_ptid))
2263 last_thread = find_thread_ptid (last_ptid);
2266 tp->suspend.stop_signal = last_thread->suspend.stop_signal;
2267 last_thread->suspend.stop_signal = GDB_SIGNAL_0;
2272 if (siggnal != GDB_SIGNAL_DEFAULT)
2273 tp->suspend.stop_signal = siggnal;
2274 /* If this signal should not be seen by program,
2275 give it zero. Used for debugging signals. */
2276 else if (!signal_program[tp->suspend.stop_signal])
2277 tp->suspend.stop_signal = GDB_SIGNAL_0;
2279 annotate_starting ();
2281 /* Make sure that output from GDB appears before output from the
2283 gdb_flush (gdb_stdout);
2285 /* Refresh prev_pc value just prior to resuming. This used to be
2286 done in stop_stepping, however, setting prev_pc there did not handle
2287 scenarios such as inferior function calls or returning from
2288 a function via the return command. In those cases, the prev_pc
2289 value was not set properly for subsequent commands. The prev_pc value
2290 is used to initialize the starting line number in the ecs. With an
2291 invalid value, the gdb next command ends up stopping at the position
2292 represented by the next line table entry past our start position.
2293 On platforms that generate one line table entry per line, this
2294 is not a problem. However, on the ia64, the compiler generates
2295 extraneous line table entries that do not increase the line number.
2296 When we issue the gdb next command on the ia64 after an inferior call
2297 or a return command, we often end up a few instructions forward, still
2298 within the original line we started.
2300 An attempt was made to refresh the prev_pc at the same time the
2301 execution_control_state is initialized (for instance, just before
2302 waiting for an inferior event). But this approach did not work
2303 because of platforms that use ptrace, where the pc register cannot
2304 be read unless the inferior is stopped. At that point, we are not
2305 guaranteed the inferior is stopped and so the regcache_read_pc() call
2306 can fail. Setting the prev_pc value here ensures the value is updated
2307 correctly when the inferior is stopped. */
2308 tp->prev_pc = regcache_read_pc (get_current_regcache ());
2310 /* Fill in with reasonable starting values. */
2311 init_thread_stepping_state (tp);
2313 /* Reset to normal state. */
2314 init_infwait_state ();
2316 /* Resume inferior. */
2317 resume (force_step || step || bpstat_should_step (),
2318 tp->suspend.stop_signal);
2320 /* Wait for it to stop (if not standalone)
2321 and in any case decode why it stopped, and act accordingly. */
2322 /* Do this only if we are not using the event loop, or if the target
2323 does not support asynchronous execution. */
2324 if (!target_can_async_p ())
2326 wait_for_inferior ();
2332 /* Start remote-debugging of a machine over a serial link. */
2335 start_remote (int from_tty)
2337 struct inferior *inferior;
2339 inferior = current_inferior ();
2340 inferior->control.stop_soon = STOP_QUIETLY_REMOTE;
2342 /* Always go on waiting for the target, regardless of the mode. */
2343 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2344 indicate to wait_for_inferior that a target should timeout if
2345 nothing is returned (instead of just blocking). Because of this,
2346 targets expecting an immediate response need to, internally, set
2347 things up so that the target_wait() is forced to eventually
2349 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2350 differentiate to its caller what the state of the target is after
2351 the initial open has been performed. Here we're assuming that
2352 the target has stopped. It should be possible to eventually have
2353 target_open() return to the caller an indication that the target
2354 is currently running and GDB state should be set to the same as
2355 for an async run. */
2356 wait_for_inferior ();
2358 /* Now that the inferior has stopped, do any bookkeeping like
2359 loading shared libraries. We want to do this before normal_stop,
2360 so that the displayed frame is up to date. */
2361 post_create_inferior (¤t_target, from_tty);
2366 /* Initialize static vars when a new inferior begins. */
2369 init_wait_for_inferior (void)
2371 /* These are meaningless until the first time through wait_for_inferior. */
2373 breakpoint_init_inferior (inf_starting);
2375 clear_proceed_status ();
2377 stepping_past_singlestep_breakpoint = 0;
2378 deferred_step_ptid = null_ptid;
2380 target_last_wait_ptid = minus_one_ptid;
2382 previous_inferior_ptid = inferior_ptid;
2383 init_infwait_state ();
2385 /* Discard any skipped inlined frames. */
2386 clear_inline_frame_state (minus_one_ptid);
2390 /* This enum encodes possible reasons for doing a target_wait, so that
2391 wfi can call target_wait in one place. (Ultimately the call will be
2392 moved out of the infinite loop entirely.) */
2396 infwait_normal_state,
2397 infwait_thread_hop_state,
2398 infwait_step_watch_state,
2399 infwait_nonstep_watch_state
2402 /* The PTID we'll do a target_wait on.*/
2405 /* Current inferior wait state. */
2406 static enum infwait_states infwait_state;
2408 /* Data to be passed around while handling an event. This data is
2409 discarded between events. */
2410 struct execution_control_state
2413 /* The thread that got the event, if this was a thread event; NULL
2415 struct thread_info *event_thread;
2417 struct target_waitstatus ws;
2419 int stop_func_filled_in;
2420 CORE_ADDR stop_func_start;
2421 CORE_ADDR stop_func_end;
2422 const char *stop_func_name;
2426 static void handle_inferior_event (struct execution_control_state *ecs);
2428 static void handle_step_into_function (struct gdbarch *gdbarch,
2429 struct execution_control_state *ecs);
2430 static void handle_step_into_function_backward (struct gdbarch *gdbarch,
2431 struct execution_control_state *ecs);
2432 static void check_exception_resume (struct execution_control_state *,
2433 struct frame_info *);
2435 static void stop_stepping (struct execution_control_state *ecs);
2436 static void prepare_to_wait (struct execution_control_state *ecs);
2437 static void keep_going (struct execution_control_state *ecs);
2439 /* Callback for iterate over threads. If the thread is stopped, but
2440 the user/frontend doesn't know about that yet, go through
2441 normal_stop, as if the thread had just stopped now. ARG points at
2442 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2443 ptid_is_pid(PTID) is true, applies to all threads of the process
2444 pointed at by PTID. Otherwise, apply only to the thread pointed by
2448 infrun_thread_stop_requested_callback (struct thread_info *info, void *arg)
2450 ptid_t ptid = * (ptid_t *) arg;
2452 if ((ptid_equal (info->ptid, ptid)
2453 || ptid_equal (minus_one_ptid, ptid)
2454 || (ptid_is_pid (ptid)
2455 && ptid_get_pid (ptid) == ptid_get_pid (info->ptid)))
2456 && is_running (info->ptid)
2457 && !is_executing (info->ptid))
2459 struct cleanup *old_chain;
2460 struct execution_control_state ecss;
2461 struct execution_control_state *ecs = &ecss;
2463 memset (ecs, 0, sizeof (*ecs));
2465 old_chain = make_cleanup_restore_current_thread ();
2467 /* Go through handle_inferior_event/normal_stop, so we always
2468 have consistent output as if the stop event had been
2470 ecs->ptid = info->ptid;
2471 ecs->event_thread = find_thread_ptid (info->ptid);
2472 ecs->ws.kind = TARGET_WAITKIND_STOPPED;
2473 ecs->ws.value.sig = GDB_SIGNAL_0;
2475 handle_inferior_event (ecs);
2477 if (!ecs->wait_some_more)
2479 struct thread_info *tp;
2483 /* Finish off the continuations. */
2484 tp = inferior_thread ();
2485 do_all_intermediate_continuations_thread (tp, 1);
2486 do_all_continuations_thread (tp, 1);
2489 do_cleanups (old_chain);
2495 /* This function is attached as a "thread_stop_requested" observer.
2496 Cleanup local state that assumed the PTID was to be resumed, and
2497 report the stop to the frontend. */
2500 infrun_thread_stop_requested (ptid_t ptid)
2502 struct displaced_step_inferior_state *displaced;
2504 /* PTID was requested to stop. Remove it from the displaced
2505 stepping queue, so we don't try to resume it automatically. */
2507 for (displaced = displaced_step_inferior_states;
2509 displaced = displaced->next)
2511 struct displaced_step_request *it, **prev_next_p;
2513 it = displaced->step_request_queue;
2514 prev_next_p = &displaced->step_request_queue;
2517 if (ptid_match (it->ptid, ptid))
2519 *prev_next_p = it->next;
2525 prev_next_p = &it->next;
2532 iterate_over_threads (infrun_thread_stop_requested_callback, &ptid);
2536 infrun_thread_thread_exit (struct thread_info *tp, int silent)
2538 if (ptid_equal (target_last_wait_ptid, tp->ptid))
2539 nullify_last_target_wait_ptid ();
2542 /* Callback for iterate_over_threads. */
2545 delete_step_resume_breakpoint_callback (struct thread_info *info, void *data)
2547 if (is_exited (info->ptid))
2550 delete_step_resume_breakpoint (info);
2551 delete_exception_resume_breakpoint (info);
2555 /* In all-stop, delete the step resume breakpoint of any thread that
2556 had one. In non-stop, delete the step resume breakpoint of the
2557 thread that just stopped. */
2560 delete_step_thread_step_resume_breakpoint (void)
2562 if (!target_has_execution
2563 || ptid_equal (inferior_ptid, null_ptid))
2564 /* If the inferior has exited, we have already deleted the step
2565 resume breakpoints out of GDB's lists. */
2570 /* If in non-stop mode, only delete the step-resume or
2571 longjmp-resume breakpoint of the thread that just stopped
2573 struct thread_info *tp = inferior_thread ();
2575 delete_step_resume_breakpoint (tp);
2576 delete_exception_resume_breakpoint (tp);
2579 /* In all-stop mode, delete all step-resume and longjmp-resume
2580 breakpoints of any thread that had them. */
2581 iterate_over_threads (delete_step_resume_breakpoint_callback, NULL);
2584 /* A cleanup wrapper. */
2587 delete_step_thread_step_resume_breakpoint_cleanup (void *arg)
2589 delete_step_thread_step_resume_breakpoint ();
2592 /* Pretty print the results of target_wait, for debugging purposes. */
2595 print_target_wait_results (ptid_t waiton_ptid, ptid_t result_ptid,
2596 const struct target_waitstatus *ws)
2598 char *status_string = target_waitstatus_to_string (ws);
2599 struct ui_file *tmp_stream = mem_fileopen ();
2602 /* The text is split over several lines because it was getting too long.
2603 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2604 output as a unit; we want only one timestamp printed if debug_timestamp
2607 fprintf_unfiltered (tmp_stream,
2608 "infrun: target_wait (%d", PIDGET (waiton_ptid));
2609 if (PIDGET (waiton_ptid) != -1)
2610 fprintf_unfiltered (tmp_stream,
2611 " [%s]", target_pid_to_str (waiton_ptid));
2612 fprintf_unfiltered (tmp_stream, ", status) =\n");
2613 fprintf_unfiltered (tmp_stream,
2614 "infrun: %d [%s],\n",
2615 PIDGET (result_ptid), target_pid_to_str (result_ptid));
2616 fprintf_unfiltered (tmp_stream,
2620 text = ui_file_xstrdup (tmp_stream, NULL);
2622 /* This uses %s in part to handle %'s in the text, but also to avoid
2623 a gcc error: the format attribute requires a string literal. */
2624 fprintf_unfiltered (gdb_stdlog, "%s", text);
2626 xfree (status_string);
2628 ui_file_delete (tmp_stream);
2631 /* Prepare and stabilize the inferior for detaching it. E.g.,
2632 detaching while a thread is displaced stepping is a recipe for
2633 crashing it, as nothing would readjust the PC out of the scratch
2637 prepare_for_detach (void)
2639 struct inferior *inf = current_inferior ();
2640 ptid_t pid_ptid = pid_to_ptid (inf->pid);
2641 struct cleanup *old_chain_1;
2642 struct displaced_step_inferior_state *displaced;
2644 displaced = get_displaced_stepping_state (inf->pid);
2646 /* Is any thread of this process displaced stepping? If not,
2647 there's nothing else to do. */
2648 if (displaced == NULL || ptid_equal (displaced->step_ptid, null_ptid))
2652 fprintf_unfiltered (gdb_stdlog,
2653 "displaced-stepping in-process while detaching");
2655 old_chain_1 = make_cleanup_restore_integer (&inf->detaching);
2658 while (!ptid_equal (displaced->step_ptid, null_ptid))
2660 struct cleanup *old_chain_2;
2661 struct execution_control_state ecss;
2662 struct execution_control_state *ecs;
2665 memset (ecs, 0, sizeof (*ecs));
2667 overlay_cache_invalid = 1;
2669 if (deprecated_target_wait_hook)
2670 ecs->ptid = deprecated_target_wait_hook (pid_ptid, &ecs->ws, 0);
2672 ecs->ptid = target_wait (pid_ptid, &ecs->ws, 0);
2675 print_target_wait_results (pid_ptid, ecs->ptid, &ecs->ws);
2677 /* If an error happens while handling the event, propagate GDB's
2678 knowledge of the executing state to the frontend/user running
2680 old_chain_2 = make_cleanup (finish_thread_state_cleanup,
2683 /* Now figure out what to do with the result of the result. */
2684 handle_inferior_event (ecs);
2686 /* No error, don't finish the state yet. */
2687 discard_cleanups (old_chain_2);
2689 /* Breakpoints and watchpoints are not installed on the target
2690 at this point, and signals are passed directly to the
2691 inferior, so this must mean the process is gone. */
2692 if (!ecs->wait_some_more)
2694 discard_cleanups (old_chain_1);
2695 error (_("Program exited while detaching"));
2699 discard_cleanups (old_chain_1);
2702 /* Wait for control to return from inferior to debugger.
2704 If inferior gets a signal, we may decide to start it up again
2705 instead of returning. That is why there is a loop in this function.
2706 When this function actually returns it means the inferior
2707 should be left stopped and GDB should read more commands. */
2710 wait_for_inferior (void)
2712 struct cleanup *old_cleanups;
2716 (gdb_stdlog, "infrun: wait_for_inferior ()\n");
2719 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup, NULL);
2723 struct execution_control_state ecss;
2724 struct execution_control_state *ecs = &ecss;
2725 struct cleanup *old_chain;
2727 memset (ecs, 0, sizeof (*ecs));
2729 overlay_cache_invalid = 1;
2731 if (deprecated_target_wait_hook)
2732 ecs->ptid = deprecated_target_wait_hook (waiton_ptid, &ecs->ws, 0);
2734 ecs->ptid = target_wait (waiton_ptid, &ecs->ws, 0);
2737 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
2739 /* If an error happens while handling the event, propagate GDB's
2740 knowledge of the executing state to the frontend/user running
2742 old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
2744 /* Now figure out what to do with the result of the result. */
2745 handle_inferior_event (ecs);
2747 /* No error, don't finish the state yet. */
2748 discard_cleanups (old_chain);
2750 if (!ecs->wait_some_more)
2754 do_cleanups (old_cleanups);
2757 /* Asynchronous version of wait_for_inferior. It is called by the
2758 event loop whenever a change of state is detected on the file
2759 descriptor corresponding to the target. It can be called more than
2760 once to complete a single execution command. In such cases we need
2761 to keep the state in a global variable ECSS. If it is the last time
2762 that this function is called for a single execution command, then
2763 report to the user that the inferior has stopped, and do the
2764 necessary cleanups. */
2767 fetch_inferior_event (void *client_data)
2769 struct execution_control_state ecss;
2770 struct execution_control_state *ecs = &ecss;
2771 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
2772 struct cleanup *ts_old_chain;
2773 int was_sync = sync_execution;
2776 memset (ecs, 0, sizeof (*ecs));
2778 /* We're handling a live event, so make sure we're doing live
2779 debugging. If we're looking at traceframes while the target is
2780 running, we're going to need to get back to that mode after
2781 handling the event. */
2784 make_cleanup_restore_current_traceframe ();
2785 set_current_traceframe (-1);
2789 /* In non-stop mode, the user/frontend should not notice a thread
2790 switch due to internal events. Make sure we reverse to the
2791 user selected thread and frame after handling the event and
2792 running any breakpoint commands. */
2793 make_cleanup_restore_current_thread ();
2795 overlay_cache_invalid = 1;
2797 make_cleanup_restore_integer (&execution_direction);
2798 execution_direction = target_execution_direction ();
2800 if (deprecated_target_wait_hook)
2802 deprecated_target_wait_hook (waiton_ptid, &ecs->ws, TARGET_WNOHANG);
2804 ecs->ptid = target_wait (waiton_ptid, &ecs->ws, TARGET_WNOHANG);
2807 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
2809 /* If an error happens while handling the event, propagate GDB's
2810 knowledge of the executing state to the frontend/user running
2813 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
2815 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &ecs->ptid);
2817 /* Get executed before make_cleanup_restore_current_thread above to apply
2818 still for the thread which has thrown the exception. */
2819 make_bpstat_clear_actions_cleanup ();
2821 /* Now figure out what to do with the result of the result. */
2822 handle_inferior_event (ecs);
2824 if (!ecs->wait_some_more)
2826 struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
2828 delete_step_thread_step_resume_breakpoint ();
2830 /* We may not find an inferior if this was a process exit. */
2831 if (inf == NULL || inf->control.stop_soon == NO_STOP_QUIETLY)
2834 if (target_has_execution
2835 && ecs->ws.kind != TARGET_WAITKIND_NO_RESUMED
2836 && ecs->ws.kind != TARGET_WAITKIND_EXITED
2837 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
2838 && ecs->event_thread->step_multi
2839 && ecs->event_thread->control.stop_step)
2840 inferior_event_handler (INF_EXEC_CONTINUE, NULL);
2843 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
2848 /* No error, don't finish the thread states yet. */
2849 discard_cleanups (ts_old_chain);
2851 /* Revert thread and frame. */
2852 do_cleanups (old_chain);
2854 /* If the inferior was in sync execution mode, and now isn't,
2855 restore the prompt (a synchronous execution command has finished,
2856 and we're ready for input). */
2857 if (interpreter_async && was_sync && !sync_execution)
2858 display_gdb_prompt (0);
2862 && exec_done_display_p
2863 && (ptid_equal (inferior_ptid, null_ptid)
2864 || !is_running (inferior_ptid)))
2865 printf_unfiltered (_("completed.\n"));
2868 /* Record the frame and location we're currently stepping through. */
2870 set_step_info (struct frame_info *frame, struct symtab_and_line sal)
2872 struct thread_info *tp = inferior_thread ();
2874 tp->control.step_frame_id = get_frame_id (frame);
2875 tp->control.step_stack_frame_id = get_stack_frame_id (frame);
2877 tp->current_symtab = sal.symtab;
2878 tp->current_line = sal.line;
2881 /* Clear context switchable stepping state. */
2884 init_thread_stepping_state (struct thread_info *tss)
2886 tss->stepping_over_breakpoint = 0;
2887 tss->step_after_step_resume_breakpoint = 0;
2890 /* Return the cached copy of the last pid/waitstatus returned by
2891 target_wait()/deprecated_target_wait_hook(). The data is actually
2892 cached by handle_inferior_event(), which gets called immediately
2893 after target_wait()/deprecated_target_wait_hook(). */
2896 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
2898 *ptidp = target_last_wait_ptid;
2899 *status = target_last_waitstatus;
2903 nullify_last_target_wait_ptid (void)
2905 target_last_wait_ptid = minus_one_ptid;
2908 /* Switch thread contexts. */
2911 context_switch (ptid_t ptid)
2913 if (debug_infrun && !ptid_equal (ptid, inferior_ptid))
2915 fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ",
2916 target_pid_to_str (inferior_ptid));
2917 fprintf_unfiltered (gdb_stdlog, "to %s\n",
2918 target_pid_to_str (ptid));
2921 switch_to_thread (ptid);
2925 adjust_pc_after_break (struct execution_control_state *ecs)
2927 struct regcache *regcache;
2928 struct gdbarch *gdbarch;
2929 struct address_space *aspace;
2930 CORE_ADDR breakpoint_pc;
2932 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2933 we aren't, just return.
2935 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2936 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2937 implemented by software breakpoints should be handled through the normal
2940 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2941 different signals (SIGILL or SIGEMT for instance), but it is less
2942 clear where the PC is pointing afterwards. It may not match
2943 gdbarch_decr_pc_after_break. I don't know any specific target that
2944 generates these signals at breakpoints (the code has been in GDB since at
2945 least 1992) so I can not guess how to handle them here.
2947 In earlier versions of GDB, a target with
2948 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2949 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2950 target with both of these set in GDB history, and it seems unlikely to be
2951 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2953 if (ecs->ws.kind != TARGET_WAITKIND_STOPPED)
2956 if (ecs->ws.value.sig != GDB_SIGNAL_TRAP)
2959 /* In reverse execution, when a breakpoint is hit, the instruction
2960 under it has already been de-executed. The reported PC always
2961 points at the breakpoint address, so adjusting it further would
2962 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2965 B1 0x08000000 : INSN1
2966 B2 0x08000001 : INSN2
2968 PC -> 0x08000003 : INSN4
2970 Say you're stopped at 0x08000003 as above. Reverse continuing
2971 from that point should hit B2 as below. Reading the PC when the
2972 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2973 been de-executed already.
2975 B1 0x08000000 : INSN1
2976 B2 PC -> 0x08000001 : INSN2
2980 We can't apply the same logic as for forward execution, because
2981 we would wrongly adjust the PC to 0x08000000, since there's a
2982 breakpoint at PC - 1. We'd then report a hit on B1, although
2983 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2985 if (execution_direction == EXEC_REVERSE)
2988 /* If this target does not decrement the PC after breakpoints, then
2989 we have nothing to do. */
2990 regcache = get_thread_regcache (ecs->ptid);
2991 gdbarch = get_regcache_arch (regcache);
2992 if (gdbarch_decr_pc_after_break (gdbarch) == 0)
2995 aspace = get_regcache_aspace (regcache);
2997 /* Find the location where (if we've hit a breakpoint) the
2998 breakpoint would be. */
2999 breakpoint_pc = regcache_read_pc (regcache)
3000 - gdbarch_decr_pc_after_break (gdbarch);
3002 /* Check whether there actually is a software breakpoint inserted at
3005 If in non-stop mode, a race condition is possible where we've
3006 removed a breakpoint, but stop events for that breakpoint were
3007 already queued and arrive later. To suppress those spurious
3008 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3009 and retire them after a number of stop events are reported. */
3010 if (software_breakpoint_inserted_here_p (aspace, breakpoint_pc)
3011 || (non_stop && moribund_breakpoint_here_p (aspace, breakpoint_pc)))
3013 struct cleanup *old_cleanups = make_cleanup (null_cleanup, NULL);
3016 record_full_gdb_operation_disable_set ();
3018 /* When using hardware single-step, a SIGTRAP is reported for both
3019 a completed single-step and a software breakpoint. Need to
3020 differentiate between the two, as the latter needs adjusting
3021 but the former does not.
3023 The SIGTRAP can be due to a completed hardware single-step only if
3024 - we didn't insert software single-step breakpoints
3025 - the thread to be examined is still the current thread
3026 - this thread is currently being stepped
3028 If any of these events did not occur, we must have stopped due
3029 to hitting a software breakpoint, and have to back up to the
3032 As a special case, we could have hardware single-stepped a
3033 software breakpoint. In this case (prev_pc == breakpoint_pc),
3034 we also need to back up to the breakpoint address. */
3036 if (singlestep_breakpoints_inserted_p
3037 || !ptid_equal (ecs->ptid, inferior_ptid)
3038 || !currently_stepping (ecs->event_thread)
3039 || ecs->event_thread->prev_pc == breakpoint_pc)
3040 regcache_write_pc (regcache, breakpoint_pc);
3042 do_cleanups (old_cleanups);
3047 init_infwait_state (void)
3049 waiton_ptid = pid_to_ptid (-1);
3050 infwait_state = infwait_normal_state;
3054 stepped_in_from (struct frame_info *frame, struct frame_id step_frame_id)
3056 for (frame = get_prev_frame (frame);
3058 frame = get_prev_frame (frame))
3060 if (frame_id_eq (get_frame_id (frame), step_frame_id))
3062 if (get_frame_type (frame) != INLINE_FRAME)
3069 /* Auxiliary function that handles syscall entry/return events.
3070 It returns 1 if the inferior should keep going (and GDB
3071 should ignore the event), or 0 if the event deserves to be
3075 handle_syscall_event (struct execution_control_state *ecs)
3077 struct regcache *regcache;
3080 if (!ptid_equal (ecs->ptid, inferior_ptid))
3081 context_switch (ecs->ptid);
3083 regcache = get_thread_regcache (ecs->ptid);
3084 syscall_number = ecs->ws.value.syscall_number;
3085 stop_pc = regcache_read_pc (regcache);
3087 if (catch_syscall_enabled () > 0
3088 && catching_syscall_number (syscall_number) > 0)
3090 enum bpstat_signal_value sval;
3093 fprintf_unfiltered (gdb_stdlog, "infrun: syscall number = '%d'\n",
3096 ecs->event_thread->control.stop_bpstat
3097 = bpstat_stop_status (get_regcache_aspace (regcache),
3098 stop_pc, ecs->ptid, &ecs->ws);
3100 sval = bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
3102 ecs->random_signal = sval == BPSTAT_SIGNAL_NO;
3104 if (!ecs->random_signal)
3106 /* Catchpoint hit. */
3107 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_TRAP;
3112 /* If no catchpoint triggered for this, then keep going. */
3113 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
3118 /* Clear the supplied execution_control_state's stop_func_* fields. */
3121 clear_stop_func (struct execution_control_state *ecs)
3123 ecs->stop_func_filled_in = 0;
3124 ecs->stop_func_start = 0;
3125 ecs->stop_func_end = 0;
3126 ecs->stop_func_name = NULL;
3129 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3132 fill_in_stop_func (struct gdbarch *gdbarch,
3133 struct execution_control_state *ecs)
3135 if (!ecs->stop_func_filled_in)
3137 /* Don't care about return value; stop_func_start and stop_func_name
3138 will both be 0 if it doesn't work. */
3139 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
3140 &ecs->stop_func_start, &ecs->stop_func_end);
3141 ecs->stop_func_start
3142 += gdbarch_deprecated_function_start_offset (gdbarch);
3144 ecs->stop_func_filled_in = 1;
3148 /* Given an execution control state that has been freshly filled in
3149 by an event from the inferior, figure out what it means and take
3150 appropriate action. */
3153 handle_inferior_event (struct execution_control_state *ecs)
3155 struct frame_info *frame;
3156 struct gdbarch *gdbarch;
3157 int stopped_by_watchpoint;
3158 int stepped_after_stopped_by_watchpoint = 0;
3159 struct symtab_and_line stop_pc_sal;
3160 enum stop_kind stop_soon;
3162 if (ecs->ws.kind == TARGET_WAITKIND_IGNORE)
3164 /* We had an event in the inferior, but we are not interested in
3165 handling it at this level. The lower layers have already
3166 done what needs to be done, if anything.
3168 One of the possible circumstances for this is when the
3169 inferior produces output for the console. The inferior has
3170 not stopped, and we are ignoring the event. Another possible
3171 circumstance is any event which the lower level knows will be
3172 reported multiple times without an intervening resume. */
3174 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n");
3175 prepare_to_wait (ecs);
3179 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED
3180 && target_can_async_p () && !sync_execution)
3182 /* There were no unwaited-for children left in the target, but,
3183 we're not synchronously waiting for events either. Just
3184 ignore. Otherwise, if we were running a synchronous
3185 execution command, we need to cancel it and give the user
3186 back the terminal. */
3188 fprintf_unfiltered (gdb_stdlog,
3189 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3190 prepare_to_wait (ecs);
3194 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
3195 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
3196 && ecs->ws.kind != TARGET_WAITKIND_NO_RESUMED)
3198 struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
3201 stop_soon = inf->control.stop_soon;
3204 stop_soon = NO_STOP_QUIETLY;
3206 /* Cache the last pid/waitstatus. */
3207 target_last_wait_ptid = ecs->ptid;
3208 target_last_waitstatus = ecs->ws;
3210 /* Always clear state belonging to the previous time we stopped. */
3211 stop_stack_dummy = STOP_NONE;
3213 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED)
3215 /* No unwaited-for children left. IOW, all resumed children
3218 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3220 stop_print_frame = 0;
3221 stop_stepping (ecs);
3225 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
3226 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
3228 ecs->event_thread = find_thread_ptid (ecs->ptid);
3229 /* If it's a new thread, add it to the thread database. */
3230 if (ecs->event_thread == NULL)
3231 ecs->event_thread = add_thread (ecs->ptid);
3233 /* Disable range stepping. If the next step request could use a
3234 range, this will be end up re-enabled then. */
3235 ecs->event_thread->control.may_range_step = 0;
3238 /* Dependent on valid ECS->EVENT_THREAD. */
3239 adjust_pc_after_break (ecs);
3241 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3242 reinit_frame_cache ();
3244 breakpoint_retire_moribund ();
3246 /* First, distinguish signals caused by the debugger from signals
3247 that have to do with the program's own actions. Note that
3248 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3249 on the operating system version. Here we detect when a SIGILL or
3250 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3251 something similar for SIGSEGV, since a SIGSEGV will be generated
3252 when we're trying to execute a breakpoint instruction on a
3253 non-executable stack. This happens for call dummy breakpoints
3254 for architectures like SPARC that place call dummies on the
3256 if (ecs->ws.kind == TARGET_WAITKIND_STOPPED
3257 && (ecs->ws.value.sig == GDB_SIGNAL_ILL
3258 || ecs->ws.value.sig == GDB_SIGNAL_SEGV
3259 || ecs->ws.value.sig == GDB_SIGNAL_EMT))
3261 struct regcache *regcache = get_thread_regcache (ecs->ptid);
3263 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache),
3264 regcache_read_pc (regcache)))
3267 fprintf_unfiltered (gdb_stdlog,
3268 "infrun: Treating signal as SIGTRAP\n");
3269 ecs->ws.value.sig = GDB_SIGNAL_TRAP;
3273 /* Mark the non-executing threads accordingly. In all-stop, all
3274 threads of all processes are stopped when we get any event
3275 reported. In non-stop mode, only the event thread stops. If
3276 we're handling a process exit in non-stop mode, there's nothing
3277 to do, as threads of the dead process are gone, and threads of
3278 any other process were left running. */
3280 set_executing (minus_one_ptid, 0);
3281 else if (ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
3282 && ecs->ws.kind != TARGET_WAITKIND_EXITED)
3283 set_executing (ecs->ptid, 0);
3285 switch (infwait_state)
3287 case infwait_thread_hop_state:
3289 fprintf_unfiltered (gdb_stdlog, "infrun: infwait_thread_hop_state\n");
3292 case infwait_normal_state:
3294 fprintf_unfiltered (gdb_stdlog, "infrun: infwait_normal_state\n");
3297 case infwait_step_watch_state:
3299 fprintf_unfiltered (gdb_stdlog,
3300 "infrun: infwait_step_watch_state\n");
3302 stepped_after_stopped_by_watchpoint = 1;
3305 case infwait_nonstep_watch_state:
3307 fprintf_unfiltered (gdb_stdlog,
3308 "infrun: infwait_nonstep_watch_state\n");
3309 insert_breakpoints ();
3311 /* FIXME-maybe: is this cleaner than setting a flag? Does it
3312 handle things like signals arriving and other things happening
3313 in combination correctly? */
3314 stepped_after_stopped_by_watchpoint = 1;
3318 internal_error (__FILE__, __LINE__, _("bad switch"));
3321 infwait_state = infwait_normal_state;
3322 waiton_ptid = pid_to_ptid (-1);
3324 switch (ecs->ws.kind)
3326 case TARGET_WAITKIND_LOADED:
3328 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n");
3329 /* Ignore gracefully during startup of the inferior, as it might
3330 be the shell which has just loaded some objects, otherwise
3331 add the symbols for the newly loaded objects. Also ignore at
3332 the beginning of an attach or remote session; we will query
3333 the full list of libraries once the connection is
3335 if (stop_soon == NO_STOP_QUIETLY)
3337 struct regcache *regcache;
3338 enum bpstat_signal_value sval;
3340 if (!ptid_equal (ecs->ptid, inferior_ptid))
3341 context_switch (ecs->ptid);
3342 regcache = get_thread_regcache (ecs->ptid);
3344 handle_solib_event ();
3346 ecs->event_thread->control.stop_bpstat
3347 = bpstat_stop_status (get_regcache_aspace (regcache),
3348 stop_pc, ecs->ptid, &ecs->ws);
3351 = bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
3353 ecs->random_signal = sval == BPSTAT_SIGNAL_NO;
3355 if (!ecs->random_signal)
3357 /* A catchpoint triggered. */
3358 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_TRAP;
3359 goto process_event_stop_test;
3362 /* If requested, stop when the dynamic linker notifies
3363 gdb of events. This allows the user to get control
3364 and place breakpoints in initializer routines for
3365 dynamically loaded objects (among other things). */
3366 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
3367 if (stop_on_solib_events)
3369 /* Make sure we print "Stopped due to solib-event" in
3371 stop_print_frame = 1;
3373 stop_stepping (ecs);
3378 /* If we are skipping through a shell, or through shared library
3379 loading that we aren't interested in, resume the program. If
3380 we're running the program normally, also resume. But stop if
3381 we're attaching or setting up a remote connection. */
3382 if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY)
3384 if (!ptid_equal (ecs->ptid, inferior_ptid))
3385 context_switch (ecs->ptid);
3387 /* Loading of shared libraries might have changed breakpoint
3388 addresses. Make sure new breakpoints are inserted. */
3389 if (stop_soon == NO_STOP_QUIETLY
3390 && !breakpoints_always_inserted_mode ())
3391 insert_breakpoints ();
3392 resume (0, GDB_SIGNAL_0);
3393 prepare_to_wait (ecs);
3399 case TARGET_WAITKIND_SPURIOUS:
3401 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3402 if (!ptid_equal (ecs->ptid, inferior_ptid))
3403 context_switch (ecs->ptid);
3404 resume (0, GDB_SIGNAL_0);
3405 prepare_to_wait (ecs);
3408 case TARGET_WAITKIND_EXITED:
3409 case TARGET_WAITKIND_SIGNALLED:
3412 if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
3413 fprintf_unfiltered (gdb_stdlog,
3414 "infrun: TARGET_WAITKIND_EXITED\n");
3416 fprintf_unfiltered (gdb_stdlog,
3417 "infrun: TARGET_WAITKIND_SIGNALLED\n");
3420 inferior_ptid = ecs->ptid;
3421 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs->ptid)));
3422 set_current_program_space (current_inferior ()->pspace);
3423 handle_vfork_child_exec_or_exit (0);
3424 target_terminal_ours (); /* Must do this before mourn anyway. */
3426 if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
3428 /* Record the exit code in the convenience variable $_exitcode, so
3429 that the user can inspect this again later. */
3430 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3431 (LONGEST) ecs->ws.value.integer);
3433 /* Also record this in the inferior itself. */
3434 current_inferior ()->has_exit_code = 1;
3435 current_inferior ()->exit_code = (LONGEST) ecs->ws.value.integer;
3437 print_exited_reason (ecs->ws.value.integer);
3440 print_signal_exited_reason (ecs->ws.value.sig);
3442 gdb_flush (gdb_stdout);
3443 target_mourn_inferior ();
3444 singlestep_breakpoints_inserted_p = 0;
3445 cancel_single_step_breakpoints ();
3446 stop_print_frame = 0;
3447 stop_stepping (ecs);
3450 /* The following are the only cases in which we keep going;
3451 the above cases end in a continue or goto. */
3452 case TARGET_WAITKIND_FORKED:
3453 case TARGET_WAITKIND_VFORKED:
3456 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
3457 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
3459 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_VFORKED\n");
3462 /* Check whether the inferior is displaced stepping. */
3464 struct regcache *regcache = get_thread_regcache (ecs->ptid);
3465 struct gdbarch *gdbarch = get_regcache_arch (regcache);
3466 struct displaced_step_inferior_state *displaced
3467 = get_displaced_stepping_state (ptid_get_pid (ecs->ptid));
3469 /* If checking displaced stepping is supported, and thread
3470 ecs->ptid is displaced stepping. */
3471 if (displaced && ptid_equal (displaced->step_ptid, ecs->ptid))
3473 struct inferior *parent_inf
3474 = find_inferior_pid (ptid_get_pid (ecs->ptid));
3475 struct regcache *child_regcache;
3476 CORE_ADDR parent_pc;
3478 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3479 indicating that the displaced stepping of syscall instruction
3480 has been done. Perform cleanup for parent process here. Note
3481 that this operation also cleans up the child process for vfork,
3482 because their pages are shared. */
3483 displaced_step_fixup (ecs->ptid, GDB_SIGNAL_TRAP);
3485 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
3487 /* Restore scratch pad for child process. */
3488 displaced_step_restore (displaced, ecs->ws.value.related_pid);
3491 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3492 the child's PC is also within the scratchpad. Set the child's PC
3493 to the parent's PC value, which has already been fixed up.
3494 FIXME: we use the parent's aspace here, although we're touching
3495 the child, because the child hasn't been added to the inferior
3496 list yet at this point. */
3499 = get_thread_arch_aspace_regcache (ecs->ws.value.related_pid,
3501 parent_inf->aspace);
3502 /* Read PC value of parent process. */
3503 parent_pc = regcache_read_pc (regcache);
3505 if (debug_displaced)
3506 fprintf_unfiltered (gdb_stdlog,
3507 "displaced: write child pc from %s to %s\n",
3509 regcache_read_pc (child_regcache)),
3510 paddress (gdbarch, parent_pc));
3512 regcache_write_pc (child_regcache, parent_pc);
3516 if (!ptid_equal (ecs->ptid, inferior_ptid))
3517 context_switch (ecs->ptid);
3519 /* Immediately detach breakpoints from the child before there's
3520 any chance of letting the user delete breakpoints from the
3521 breakpoint lists. If we don't do this early, it's easy to
3522 leave left over traps in the child, vis: "break foo; catch
3523 fork; c; <fork>; del; c; <child calls foo>". We only follow
3524 the fork on the last `continue', and by that time the
3525 breakpoint at "foo" is long gone from the breakpoint table.
3526 If we vforked, then we don't need to unpatch here, since both
3527 parent and child are sharing the same memory pages; we'll
3528 need to unpatch at follow/detach time instead to be certain
3529 that new breakpoints added between catchpoint hit time and
3530 vfork follow are detached. */
3531 if (ecs->ws.kind != TARGET_WAITKIND_VFORKED)
3533 /* This won't actually modify the breakpoint list, but will
3534 physically remove the breakpoints from the child. */
3535 detach_breakpoints (ecs->ws.value.related_pid);
3538 if (singlestep_breakpoints_inserted_p)
3540 /* Pull the single step breakpoints out of the target. */
3541 remove_single_step_breakpoints ();
3542 singlestep_breakpoints_inserted_p = 0;
3545 /* In case the event is caught by a catchpoint, remember that
3546 the event is to be followed at the next resume of the thread,
3547 and not immediately. */
3548 ecs->event_thread->pending_follow = ecs->ws;
3550 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3552 ecs->event_thread->control.stop_bpstat
3553 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3554 stop_pc, ecs->ptid, &ecs->ws);
3556 /* Note that we're interested in knowing the bpstat actually
3557 causes a stop, not just if it may explain the signal.
3558 Software watchpoints, for example, always appear in the
3561 = !bpstat_causes_stop (ecs->event_thread->control.stop_bpstat);
3563 /* If no catchpoint triggered for this, then keep going. */
3564 if (ecs->random_signal)
3570 = (follow_fork_mode_string == follow_fork_mode_child);
3572 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
3574 should_resume = follow_fork ();
3577 child = ecs->ws.value.related_pid;
3579 /* In non-stop mode, also resume the other branch. */
3580 if (non_stop && !detach_fork)
3583 switch_to_thread (parent);
3585 switch_to_thread (child);
3587 ecs->event_thread = inferior_thread ();
3588 ecs->ptid = inferior_ptid;
3593 switch_to_thread (child);
3595 switch_to_thread (parent);
3597 ecs->event_thread = inferior_thread ();
3598 ecs->ptid = inferior_ptid;
3603 stop_stepping (ecs);
3606 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_TRAP;
3607 goto process_event_stop_test;
3609 case TARGET_WAITKIND_VFORK_DONE:
3610 /* Done with the shared memory region. Re-insert breakpoints in
3611 the parent, and keep going. */
3614 fprintf_unfiltered (gdb_stdlog,
3615 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3617 if (!ptid_equal (ecs->ptid, inferior_ptid))
3618 context_switch (ecs->ptid);
3620 current_inferior ()->waiting_for_vfork_done = 0;
3621 current_inferior ()->pspace->breakpoints_not_allowed = 0;
3622 /* This also takes care of reinserting breakpoints in the
3623 previously locked inferior. */
3627 case TARGET_WAITKIND_EXECD:
3629 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n");
3631 if (!ptid_equal (ecs->ptid, inferior_ptid))
3632 context_switch (ecs->ptid);
3634 singlestep_breakpoints_inserted_p = 0;
3635 cancel_single_step_breakpoints ();
3637 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3639 /* Do whatever is necessary to the parent branch of the vfork. */
3640 handle_vfork_child_exec_or_exit (1);
3642 /* This causes the eventpoints and symbol table to be reset.
3643 Must do this now, before trying to determine whether to
3645 follow_exec (inferior_ptid, ecs->ws.value.execd_pathname);
3647 ecs->event_thread->control.stop_bpstat
3648 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3649 stop_pc, ecs->ptid, &ecs->ws);
3651 = (bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
3653 == BPSTAT_SIGNAL_NO);
3655 /* Note that this may be referenced from inside
3656 bpstat_stop_status above, through inferior_has_execd. */
3657 xfree (ecs->ws.value.execd_pathname);
3658 ecs->ws.value.execd_pathname = NULL;
3660 /* If no catchpoint triggered for this, then keep going. */
3661 if (ecs->random_signal)
3663 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
3667 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_TRAP;
3668 goto process_event_stop_test;
3670 /* Be careful not to try to gather much state about a thread
3671 that's in a syscall. It's frequently a losing proposition. */
3672 case TARGET_WAITKIND_SYSCALL_ENTRY:
3674 fprintf_unfiltered (gdb_stdlog,
3675 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3676 /* Getting the current syscall number. */
3677 if (handle_syscall_event (ecs) != 0)
3679 goto process_event_stop_test;
3681 /* Before examining the threads further, step this thread to
3682 get it entirely out of the syscall. (We get notice of the
3683 event when the thread is just on the verge of exiting a
3684 syscall. Stepping one instruction seems to get it back
3686 case TARGET_WAITKIND_SYSCALL_RETURN:
3688 fprintf_unfiltered (gdb_stdlog,
3689 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3690 if (handle_syscall_event (ecs) != 0)
3692 goto process_event_stop_test;
3694 case TARGET_WAITKIND_STOPPED:
3696 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n");
3697 ecs->event_thread->suspend.stop_signal = ecs->ws.value.sig;
3700 case TARGET_WAITKIND_NO_HISTORY:
3702 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
3703 /* Reverse execution: target ran out of history info. */
3705 /* Pull the single step breakpoints out of the target. */
3706 if (singlestep_breakpoints_inserted_p)
3708 if (!ptid_equal (ecs->ptid, inferior_ptid))
3709 context_switch (ecs->ptid);
3710 remove_single_step_breakpoints ();
3711 singlestep_breakpoints_inserted_p = 0;
3713 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3714 print_no_history_reason ();
3715 stop_stepping (ecs);
3719 if (ecs->ws.kind == TARGET_WAITKIND_STOPPED)
3721 /* Do we need to clean up the state of a thread that has
3722 completed a displaced single-step? (Doing so usually affects
3723 the PC, so do it here, before we set stop_pc.) */
3724 displaced_step_fixup (ecs->ptid,
3725 ecs->event_thread->suspend.stop_signal);
3727 /* If we either finished a single-step or hit a breakpoint, but
3728 the user wanted this thread to be stopped, pretend we got a
3729 SIG0 (generic unsignaled stop). */
3731 if (ecs->event_thread->stop_requested
3732 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
3733 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
3736 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3740 struct regcache *regcache = get_thread_regcache (ecs->ptid);
3741 struct gdbarch *gdbarch = get_regcache_arch (regcache);
3742 struct cleanup *old_chain = save_inferior_ptid ();
3744 inferior_ptid = ecs->ptid;
3746 fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = %s\n",
3747 paddress (gdbarch, stop_pc));
3748 if (target_stopped_by_watchpoint ())
3752 fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n");
3754 if (target_stopped_data_address (¤t_target, &addr))
3755 fprintf_unfiltered (gdb_stdlog,
3756 "infrun: stopped data address = %s\n",
3757 paddress (gdbarch, addr));
3759 fprintf_unfiltered (gdb_stdlog,
3760 "infrun: (no data address available)\n");
3763 do_cleanups (old_chain);
3766 if (stepping_past_singlestep_breakpoint)
3768 gdb_assert (singlestep_breakpoints_inserted_p);
3769 gdb_assert (ptid_equal (singlestep_ptid, ecs->ptid));
3770 gdb_assert (!ptid_equal (singlestep_ptid, saved_singlestep_ptid));
3772 stepping_past_singlestep_breakpoint = 0;
3774 /* We've either finished single-stepping past the single-step
3775 breakpoint, or stopped for some other reason. It would be nice if
3776 we could tell, but we can't reliably. */
3777 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
3780 fprintf_unfiltered (gdb_stdlog,
3781 "infrun: stepping_past_"
3782 "singlestep_breakpoint\n");
3783 /* Pull the single step breakpoints out of the target. */
3784 if (!ptid_equal (ecs->ptid, inferior_ptid))
3785 context_switch (ecs->ptid);
3786 remove_single_step_breakpoints ();
3787 singlestep_breakpoints_inserted_p = 0;
3789 ecs->random_signal = 0;
3790 ecs->event_thread->control.trap_expected = 0;
3792 context_switch (saved_singlestep_ptid);
3793 if (deprecated_context_hook)
3794 deprecated_context_hook (pid_to_thread_id (saved_singlestep_ptid));
3796 resume (1, GDB_SIGNAL_0);
3797 prepare_to_wait (ecs);
3802 if (!ptid_equal (deferred_step_ptid, null_ptid))
3804 /* In non-stop mode, there's never a deferred_step_ptid set. */
3805 gdb_assert (!non_stop);
3807 /* If we stopped for some other reason than single-stepping, ignore
3808 the fact that we were supposed to switch back. */
3809 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
3812 fprintf_unfiltered (gdb_stdlog,
3813 "infrun: handling deferred step\n");
3815 /* Pull the single step breakpoints out of the target. */
3816 if (singlestep_breakpoints_inserted_p)
3818 if (!ptid_equal (ecs->ptid, inferior_ptid))
3819 context_switch (ecs->ptid);
3820 remove_single_step_breakpoints ();
3821 singlestep_breakpoints_inserted_p = 0;
3824 ecs->event_thread->control.trap_expected = 0;
3826 context_switch (deferred_step_ptid);
3827 deferred_step_ptid = null_ptid;
3828 /* Suppress spurious "Switching to ..." message. */
3829 previous_inferior_ptid = inferior_ptid;
3831 resume (1, GDB_SIGNAL_0);
3832 prepare_to_wait (ecs);
3836 deferred_step_ptid = null_ptid;
3839 /* See if a thread hit a thread-specific breakpoint that was meant for
3840 another thread. If so, then step that thread past the breakpoint,
3843 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
3845 int thread_hop_needed = 0;
3846 struct address_space *aspace =
3847 get_regcache_aspace (get_thread_regcache (ecs->ptid));
3849 /* Check if a regular breakpoint has been hit before checking
3850 for a potential single step breakpoint. Otherwise, GDB will
3851 not see this breakpoint hit when stepping onto breakpoints. */
3852 if (regular_breakpoint_inserted_here_p (aspace, stop_pc))
3854 ecs->random_signal = 0;
3855 if (!breakpoint_thread_match (aspace, stop_pc, ecs->ptid))
3856 thread_hop_needed = 1;
3858 else if (singlestep_breakpoints_inserted_p)
3860 /* We have not context switched yet, so this should be true
3861 no matter which thread hit the singlestep breakpoint. */
3862 gdb_assert (ptid_equal (inferior_ptid, singlestep_ptid));
3864 fprintf_unfiltered (gdb_stdlog, "infrun: software single step "
3866 target_pid_to_str (ecs->ptid));
3868 ecs->random_signal = 0;
3869 /* The call to in_thread_list is necessary because PTIDs sometimes
3870 change when we go from single-threaded to multi-threaded. If
3871 the singlestep_ptid is still in the list, assume that it is
3872 really different from ecs->ptid. */
3873 if (!ptid_equal (singlestep_ptid, ecs->ptid)
3874 && in_thread_list (singlestep_ptid))
3876 /* If the PC of the thread we were trying to single-step
3877 has changed, discard this event (which we were going
3878 to ignore anyway), and pretend we saw that thread
3879 trap. This prevents us continuously moving the
3880 single-step breakpoint forward, one instruction at a
3881 time. If the PC has changed, then the thread we were
3882 trying to single-step has trapped or been signalled,
3883 but the event has not been reported to GDB yet.
3885 There might be some cases where this loses signal
3886 information, if a signal has arrived at exactly the
3887 same time that the PC changed, but this is the best
3888 we can do with the information available. Perhaps we
3889 should arrange to report all events for all threads
3890 when they stop, or to re-poll the remote looking for
3891 this particular thread (i.e. temporarily enable
3894 CORE_ADDR new_singlestep_pc
3895 = regcache_read_pc (get_thread_regcache (singlestep_ptid));
3897 if (new_singlestep_pc != singlestep_pc)
3899 enum gdb_signal stop_signal;
3902 fprintf_unfiltered (gdb_stdlog, "infrun: unexpected thread,"
3903 " but expected thread advanced also\n");
3905 /* The current context still belongs to
3906 singlestep_ptid. Don't swap here, since that's
3907 the context we want to use. Just fudge our
3908 state and continue. */
3909 stop_signal = ecs->event_thread->suspend.stop_signal;
3910 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
3911 ecs->ptid = singlestep_ptid;
3912 ecs->event_thread = find_thread_ptid (ecs->ptid);
3913 ecs->event_thread->suspend.stop_signal = stop_signal;
3914 stop_pc = new_singlestep_pc;
3919 fprintf_unfiltered (gdb_stdlog,
3920 "infrun: unexpected thread\n");
3922 thread_hop_needed = 1;
3923 stepping_past_singlestep_breakpoint = 1;
3924 saved_singlestep_ptid = singlestep_ptid;
3929 if (thread_hop_needed)
3931 struct regcache *thread_regcache;
3932 int remove_status = 0;
3935 fprintf_unfiltered (gdb_stdlog, "infrun: thread_hop_needed\n");
3937 /* Switch context before touching inferior memory, the
3938 previous thread may have exited. */
3939 if (!ptid_equal (inferior_ptid, ecs->ptid))
3940 context_switch (ecs->ptid);
3942 /* Saw a breakpoint, but it was hit by the wrong thread.
3945 if (singlestep_breakpoints_inserted_p)
3947 /* Pull the single step breakpoints out of the target. */
3948 remove_single_step_breakpoints ();
3949 singlestep_breakpoints_inserted_p = 0;
3952 /* If the arch can displace step, don't remove the
3954 thread_regcache = get_thread_regcache (ecs->ptid);
3955 if (!use_displaced_stepping (get_regcache_arch (thread_regcache)))
3956 remove_status = remove_breakpoints ();
3958 /* Did we fail to remove breakpoints? If so, try
3959 to set the PC past the bp. (There's at least
3960 one situation in which we can fail to remove
3961 the bp's: On HP-UX's that use ttrace, we can't
3962 change the address space of a vforking child
3963 process until the child exits (well, okay, not
3964 then either :-) or execs. */
3965 if (remove_status != 0)
3966 error (_("Cannot step over breakpoint hit in wrong thread"));
3971 /* Only need to require the next event from this
3972 thread in all-stop mode. */
3973 waiton_ptid = ecs->ptid;
3974 infwait_state = infwait_thread_hop_state;
3977 ecs->event_thread->stepping_over_breakpoint = 1;
3982 else if (singlestep_breakpoints_inserted_p)
3984 ecs->random_signal = 0;
3988 ecs->random_signal = 1;
3990 /* See if something interesting happened to the non-current thread. If
3991 so, then switch to that thread. */
3992 if (!ptid_equal (ecs->ptid, inferior_ptid))
3995 fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n");
3997 context_switch (ecs->ptid);
3999 if (deprecated_context_hook)
4000 deprecated_context_hook (pid_to_thread_id (ecs->ptid));
4003 /* At this point, get hold of the now-current thread's frame. */
4004 frame = get_current_frame ();
4005 gdbarch = get_frame_arch (frame);
4007 if (singlestep_breakpoints_inserted_p)
4009 /* Pull the single step breakpoints out of the target. */
4010 remove_single_step_breakpoints ();
4011 singlestep_breakpoints_inserted_p = 0;
4014 if (stepped_after_stopped_by_watchpoint)
4015 stopped_by_watchpoint = 0;
4017 stopped_by_watchpoint = watchpoints_triggered (&ecs->ws);
4019 /* If necessary, step over this watchpoint. We'll be back to display
4021 if (stopped_by_watchpoint
4022 && (target_have_steppable_watchpoint
4023 || gdbarch_have_nonsteppable_watchpoint (gdbarch)))
4025 /* At this point, we are stopped at an instruction which has
4026 attempted to write to a piece of memory under control of
4027 a watchpoint. The instruction hasn't actually executed
4028 yet. If we were to evaluate the watchpoint expression
4029 now, we would get the old value, and therefore no change
4030 would seem to have occurred.
4032 In order to make watchpoints work `right', we really need
4033 to complete the memory write, and then evaluate the
4034 watchpoint expression. We do this by single-stepping the
4037 It may not be necessary to disable the watchpoint to stop over
4038 it. For example, the PA can (with some kernel cooperation)
4039 single step over a watchpoint without disabling the watchpoint.
4041 It is far more common to need to disable a watchpoint to step
4042 the inferior over it. If we have non-steppable watchpoints,
4043 we must disable the current watchpoint; it's simplest to
4044 disable all watchpoints and breakpoints. */
4047 if (!target_have_steppable_watchpoint)
4049 remove_breakpoints ();
4050 /* See comment in resume why we need to stop bypassing signals
4051 while breakpoints have been removed. */
4052 target_pass_signals (0, NULL);
4055 hw_step = maybe_software_singlestep (gdbarch, stop_pc);
4056 target_resume (ecs->ptid, hw_step, GDB_SIGNAL_0);
4057 waiton_ptid = ecs->ptid;
4058 if (target_have_steppable_watchpoint)
4059 infwait_state = infwait_step_watch_state;
4061 infwait_state = infwait_nonstep_watch_state;
4062 prepare_to_wait (ecs);
4066 clear_stop_func (ecs);
4067 ecs->event_thread->stepping_over_breakpoint = 0;
4068 bpstat_clear (&ecs->event_thread->control.stop_bpstat);
4069 ecs->event_thread->control.stop_step = 0;
4070 stop_print_frame = 1;
4071 ecs->random_signal = 0;
4072 stopped_by_random_signal = 0;
4074 /* Hide inlined functions starting here, unless we just performed stepi or
4075 nexti. After stepi and nexti, always show the innermost frame (not any
4076 inline function call sites). */
4077 if (ecs->event_thread->control.step_range_end != 1)
4079 struct address_space *aspace =
4080 get_regcache_aspace (get_thread_regcache (ecs->ptid));
4082 /* skip_inline_frames is expensive, so we avoid it if we can
4083 determine that the address is one where functions cannot have
4084 been inlined. This improves performance with inferiors that
4085 load a lot of shared libraries, because the solib event
4086 breakpoint is defined as the address of a function (i.e. not
4087 inline). Note that we have to check the previous PC as well
4088 as the current one to catch cases when we have just
4089 single-stepped off a breakpoint prior to reinstating it.
4090 Note that we're assuming that the code we single-step to is
4091 not inline, but that's not definitive: there's nothing
4092 preventing the event breakpoint function from containing
4093 inlined code, and the single-step ending up there. If the
4094 user had set a breakpoint on that inlined code, the missing
4095 skip_inline_frames call would break things. Fortunately
4096 that's an extremely unlikely scenario. */
4097 if (!pc_at_non_inline_function (aspace, stop_pc, &ecs->ws)
4098 && !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
4099 && ecs->event_thread->control.trap_expected
4100 && pc_at_non_inline_function (aspace,
4101 ecs->event_thread->prev_pc,
4104 skip_inline_frames (ecs->ptid);
4106 /* Re-fetch current thread's frame in case that invalidated
4108 frame = get_current_frame ();
4109 gdbarch = get_frame_arch (frame);
4113 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
4114 && ecs->event_thread->control.trap_expected
4115 && gdbarch_single_step_through_delay_p (gdbarch)
4116 && currently_stepping (ecs->event_thread))
4118 /* We're trying to step off a breakpoint. Turns out that we're
4119 also on an instruction that needs to be stepped multiple
4120 times before it's been fully executing. E.g., architectures
4121 with a delay slot. It needs to be stepped twice, once for
4122 the instruction and once for the delay slot. */
4123 int step_through_delay
4124 = gdbarch_single_step_through_delay (gdbarch, frame);
4126 if (debug_infrun && step_through_delay)
4127 fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n");
4128 if (ecs->event_thread->control.step_range_end == 0
4129 && step_through_delay)
4131 /* The user issued a continue when stopped at a breakpoint.
4132 Set up for another trap and get out of here. */
4133 ecs->event_thread->stepping_over_breakpoint = 1;
4137 else if (step_through_delay)
4139 /* The user issued a step when stopped at a breakpoint.
4140 Maybe we should stop, maybe we should not - the delay
4141 slot *might* correspond to a line of source. In any
4142 case, don't decide that here, just set
4143 ecs->stepping_over_breakpoint, making sure we
4144 single-step again before breakpoints are re-inserted. */
4145 ecs->event_thread->stepping_over_breakpoint = 1;
4149 /* Look at the cause of the stop, and decide what to do.
4150 The alternatives are:
4151 1) stop_stepping and return; to really stop and return to the debugger,
4152 2) keep_going and return to start up again
4153 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
4154 3) set ecs->random_signal to 1, and the decision between 1 and 2
4155 will be made according to the signal handling tables. */
4157 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
4161 fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n");
4162 stop_print_frame = 0;
4163 stop_stepping (ecs);
4167 /* This is originated from start_remote(), start_inferior() and
4168 shared libraries hook functions. */
4169 if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE)
4172 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
4173 stop_stepping (ecs);
4177 /* This originates from attach_command(). We need to overwrite
4178 the stop_signal here, because some kernels don't ignore a
4179 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4180 See more comments in inferior.h. On the other hand, if we
4181 get a non-SIGSTOP, report it to the user - assume the backend
4182 will handle the SIGSTOP if it should show up later.
4184 Also consider that the attach is complete when we see a
4185 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4186 target extended-remote report it instead of a SIGSTOP
4187 (e.g. gdbserver). We already rely on SIGTRAP being our
4188 signal, so this is no exception.
4190 Also consider that the attach is complete when we see a
4191 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4192 the target to stop all threads of the inferior, in case the
4193 low level attach operation doesn't stop them implicitly. If
4194 they weren't stopped implicitly, then the stub will report a
4195 GDB_SIGNAL_0, meaning: stopped for no particular reason
4196 other than GDB's request. */
4197 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
4198 && (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_STOP
4199 || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
4200 || ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_0))
4202 stop_stepping (ecs);
4203 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
4207 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4208 handles this event. */
4209 ecs->event_thread->control.stop_bpstat
4210 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4211 stop_pc, ecs->ptid, &ecs->ws);
4213 /* Following in case break condition called a
4215 stop_print_frame = 1;
4217 /* This is where we handle "moribund" watchpoints. Unlike
4218 software breakpoints traps, hardware watchpoint traps are
4219 always distinguishable from random traps. If no high-level
4220 watchpoint is associated with the reported stop data address
4221 anymore, then the bpstat does not explain the signal ---
4222 simply make sure to ignore it if `stopped_by_watchpoint' is
4226 && ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
4227 && (bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
4229 == BPSTAT_SIGNAL_NO)
4230 && stopped_by_watchpoint)
4231 fprintf_unfiltered (gdb_stdlog,
4232 "infrun: no user watchpoint explains "
4233 "watchpoint SIGTRAP, ignoring\n");
4235 /* NOTE: cagney/2003-03-29: These two checks for a random signal
4236 at one stage in the past included checks for an inferior
4237 function call's call dummy's return breakpoint. The original
4238 comment, that went with the test, read:
4240 ``End of a stack dummy. Some systems (e.g. Sony news) give
4241 another signal besides SIGTRAP, so check here as well as
4244 If someone ever tries to get call dummys on a
4245 non-executable stack to work (where the target would stop
4246 with something like a SIGSEGV), then those tests might need
4247 to be re-instated. Given, however, that the tests were only
4248 enabled when momentary breakpoints were not being used, I
4249 suspect that it won't be the case.
4251 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4252 be necessary for call dummies on a non-executable stack on
4255 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP)
4257 = !((bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
4259 != BPSTAT_SIGNAL_NO)
4260 || stopped_by_watchpoint
4261 || ecs->event_thread->control.trap_expected
4262 || (ecs->event_thread->control.step_range_end
4263 && (ecs->event_thread->control.step_resume_breakpoint
4267 enum bpstat_signal_value sval;
4269 sval = bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
4270 ecs->event_thread->suspend.stop_signal);
4271 ecs->random_signal = (sval == BPSTAT_SIGNAL_NO);
4273 if (sval == BPSTAT_SIGNAL_HIDE)
4274 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_TRAP;
4277 process_event_stop_test:
4279 /* Re-fetch current thread's frame in case we did a
4280 "goto process_event_stop_test" above. */
4281 frame = get_current_frame ();
4282 gdbarch = get_frame_arch (frame);
4284 /* For the program's own signals, act according to
4285 the signal handling tables. */
4287 if (ecs->random_signal)
4289 /* Signal not for debugging purposes. */
4291 struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
4294 fprintf_unfiltered (gdb_stdlog, "infrun: random signal %d\n",
4295 ecs->event_thread->suspend.stop_signal);
4297 stopped_by_random_signal = 1;
4299 if (signal_print[ecs->event_thread->suspend.stop_signal])
4302 target_terminal_ours_for_output ();
4303 print_signal_received_reason
4304 (ecs->event_thread->suspend.stop_signal);
4306 /* Always stop on signals if we're either just gaining control
4307 of the program, or the user explicitly requested this thread
4308 to remain stopped. */
4309 if (stop_soon != NO_STOP_QUIETLY
4310 || ecs->event_thread->stop_requested
4312 && signal_stop_state (ecs->event_thread->suspend.stop_signal)))
4314 stop_stepping (ecs);
4317 /* If not going to stop, give terminal back
4318 if we took it away. */
4320 target_terminal_inferior ();
4322 /* Clear the signal if it should not be passed. */
4323 if (signal_program[ecs->event_thread->suspend.stop_signal] == 0)
4324 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
4326 if (ecs->event_thread->prev_pc == stop_pc
4327 && ecs->event_thread->control.trap_expected
4328 && ecs->event_thread->control.step_resume_breakpoint == NULL)
4330 /* We were just starting a new sequence, attempting to
4331 single-step off of a breakpoint and expecting a SIGTRAP.
4332 Instead this signal arrives. This signal will take us out
4333 of the stepping range so GDB needs to remember to, when
4334 the signal handler returns, resume stepping off that
4336 /* To simplify things, "continue" is forced to use the same
4337 code paths as single-step - set a breakpoint at the
4338 signal return address and then, once hit, step off that
4341 fprintf_unfiltered (gdb_stdlog,
4342 "infrun: signal arrived while stepping over "
4345 insert_hp_step_resume_breakpoint_at_frame (frame);
4346 ecs->event_thread->step_after_step_resume_breakpoint = 1;
4347 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4348 ecs->event_thread->control.trap_expected = 0;
4353 if (ecs->event_thread->control.step_range_end != 0
4354 && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_0
4355 && pc_in_thread_step_range (stop_pc, ecs->event_thread)
4356 && frame_id_eq (get_stack_frame_id (frame),
4357 ecs->event_thread->control.step_stack_frame_id)
4358 && ecs->event_thread->control.step_resume_breakpoint == NULL)
4360 /* The inferior is about to take a signal that will take it
4361 out of the single step range. Set a breakpoint at the
4362 current PC (which is presumably where the signal handler
4363 will eventually return) and then allow the inferior to
4366 Note that this is only needed for a signal delivered
4367 while in the single-step range. Nested signals aren't a
4368 problem as they eventually all return. */
4370 fprintf_unfiltered (gdb_stdlog,
4371 "infrun: signal may take us out of "
4372 "single-step range\n");
4374 insert_hp_step_resume_breakpoint_at_frame (frame);
4375 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4376 ecs->event_thread->control.trap_expected = 0;
4381 /* Note: step_resume_breakpoint may be non-NULL. This occures
4382 when either there's a nested signal, or when there's a
4383 pending signal enabled just as the signal handler returns
4384 (leaving the inferior at the step-resume-breakpoint without
4385 actually executing it). Either way continue until the
4386 breakpoint is really hit. */
4390 /* Handle cases caused by hitting a breakpoint. */
4392 CORE_ADDR jmp_buf_pc;
4393 struct bpstat_what what;
4395 what = bpstat_what (ecs->event_thread->control.stop_bpstat);
4397 if (what.call_dummy)
4399 stop_stack_dummy = what.call_dummy;
4402 /* If we hit an internal event that triggers symbol changes, the
4403 current frame will be invalidated within bpstat_what (e.g.,
4404 if we hit an internal solib event). Re-fetch it. */
4405 frame = get_current_frame ();
4406 gdbarch = get_frame_arch (frame);
4408 switch (what.main_action)
4410 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
4411 /* If we hit the breakpoint at longjmp while stepping, we
4412 install a momentary breakpoint at the target of the
4416 fprintf_unfiltered (gdb_stdlog,
4417 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4419 ecs->event_thread->stepping_over_breakpoint = 1;
4421 if (what.is_longjmp)
4423 struct value *arg_value;
4425 /* If we set the longjmp breakpoint via a SystemTap
4426 probe, then use it to extract the arguments. The
4427 destination PC is the third argument to the
4429 arg_value = probe_safe_evaluate_at_pc (frame, 2);
4431 jmp_buf_pc = value_as_address (arg_value);
4432 else if (!gdbarch_get_longjmp_target_p (gdbarch)
4433 || !gdbarch_get_longjmp_target (gdbarch,
4434 frame, &jmp_buf_pc))
4437 fprintf_unfiltered (gdb_stdlog,
4438 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4439 "(!gdbarch_get_longjmp_target)\n");
4444 /* Insert a breakpoint at resume address. */
4445 insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc);
4448 check_exception_resume (ecs, frame);
4452 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
4454 struct frame_info *init_frame;
4456 /* There are several cases to consider.
4458 1. The initiating frame no longer exists. In this case
4459 we must stop, because the exception or longjmp has gone
4462 2. The initiating frame exists, and is the same as the
4463 current frame. We stop, because the exception or
4464 longjmp has been caught.
4466 3. The initiating frame exists and is different from
4467 the current frame. This means the exception or longjmp
4468 has been caught beneath the initiating frame, so keep
4471 4. longjmp breakpoint has been placed just to protect
4472 against stale dummy frames and user is not interested
4473 in stopping around longjmps. */
4476 fprintf_unfiltered (gdb_stdlog,
4477 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4479 gdb_assert (ecs->event_thread->control.exception_resume_breakpoint
4481 delete_exception_resume_breakpoint (ecs->event_thread);
4483 if (what.is_longjmp)
4485 check_longjmp_breakpoint_for_call_dummy (ecs->event_thread->num);
4487 if (!frame_id_p (ecs->event_thread->initiating_frame))
4495 init_frame = frame_find_by_id (ecs->event_thread->initiating_frame);
4499 struct frame_id current_id
4500 = get_frame_id (get_current_frame ());
4501 if (frame_id_eq (current_id,
4502 ecs->event_thread->initiating_frame))
4504 /* Case 2. Fall through. */
4514 /* For Cases 1 and 2, remove the step-resume breakpoint,
4516 delete_step_resume_breakpoint (ecs->event_thread);
4518 ecs->event_thread->control.stop_step = 1;
4519 print_end_stepping_range_reason ();
4520 stop_stepping (ecs);
4524 case BPSTAT_WHAT_SINGLE:
4526 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
4527 ecs->event_thread->stepping_over_breakpoint = 1;
4528 /* Still need to check other stuff, at least the case where
4529 we are stepping and step out of the right range. */
4532 case BPSTAT_WHAT_STEP_RESUME:
4534 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4536 delete_step_resume_breakpoint (ecs->event_thread);
4537 if (ecs->event_thread->control.proceed_to_finish
4538 && execution_direction == EXEC_REVERSE)
4540 struct thread_info *tp = ecs->event_thread;
4542 /* We are finishing a function in reverse, and just hit
4543 the step-resume breakpoint at the start address of
4544 the function, and we're almost there -- just need to
4545 back up by one more single-step, which should take us
4546 back to the function call. */
4547 tp->control.step_range_start = tp->control.step_range_end = 1;
4551 fill_in_stop_func (gdbarch, ecs);
4552 if (stop_pc == ecs->stop_func_start
4553 && execution_direction == EXEC_REVERSE)
4555 /* We are stepping over a function call in reverse, and
4556 just hit the step-resume breakpoint at the start
4557 address of the function. Go back to single-stepping,
4558 which should take us back to the function call. */
4559 ecs->event_thread->stepping_over_breakpoint = 1;
4565 case BPSTAT_WHAT_STOP_NOISY:
4567 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4568 stop_print_frame = 1;
4570 /* We are about to nuke the step_resume_breakpointt via the
4571 cleanup chain, so no need to worry about it here. */
4573 stop_stepping (ecs);
4576 case BPSTAT_WHAT_STOP_SILENT:
4578 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4579 stop_print_frame = 0;
4581 /* We are about to nuke the step_resume_breakpoin via the
4582 cleanup chain, so no need to worry about it here. */
4584 stop_stepping (ecs);
4587 case BPSTAT_WHAT_HP_STEP_RESUME:
4589 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4591 delete_step_resume_breakpoint (ecs->event_thread);
4592 if (ecs->event_thread->step_after_step_resume_breakpoint)
4594 /* Back when the step-resume breakpoint was inserted, we
4595 were trying to single-step off a breakpoint. Go back
4597 ecs->event_thread->step_after_step_resume_breakpoint = 0;
4598 ecs->event_thread->stepping_over_breakpoint = 1;
4604 case BPSTAT_WHAT_KEEP_CHECKING:
4609 /* We come here if we hit a breakpoint but should not
4610 stop for it. Possibly we also were stepping
4611 and should stop for that. So fall through and
4612 test for stepping. But, if not stepping,
4615 /* In all-stop mode, if we're currently stepping but have stopped in
4616 some other thread, we need to switch back to the stepped thread. */
4619 struct thread_info *tp;
4621 tp = iterate_over_threads (currently_stepping_or_nexting_callback,
4625 /* However, if the current thread is blocked on some internal
4626 breakpoint, and we simply need to step over that breakpoint
4627 to get it going again, do that first. */
4628 if ((ecs->event_thread->control.trap_expected
4629 && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_TRAP)
4630 || ecs->event_thread->stepping_over_breakpoint)
4636 /* If the stepping thread exited, then don't try to switch
4637 back and resume it, which could fail in several different
4638 ways depending on the target. Instead, just keep going.
4640 We can find a stepping dead thread in the thread list in
4643 - The target supports thread exit events, and when the
4644 target tries to delete the thread from the thread list,
4645 inferior_ptid pointed at the exiting thread. In such
4646 case, calling delete_thread does not really remove the
4647 thread from the list; instead, the thread is left listed,
4648 with 'exited' state.
4650 - The target's debug interface does not support thread
4651 exit events, and so we have no idea whatsoever if the
4652 previously stepping thread is still alive. For that
4653 reason, we need to synchronously query the target
4655 if (is_exited (tp->ptid)
4656 || !target_thread_alive (tp->ptid))
4659 fprintf_unfiltered (gdb_stdlog,
4660 "infrun: not switching back to "
4661 "stepped thread, it has vanished\n");
4663 delete_thread (tp->ptid);
4668 /* Otherwise, we no longer expect a trap in the current thread.
4669 Clear the trap_expected flag before switching back -- this is
4670 what keep_going would do as well, if we called it. */
4671 ecs->event_thread->control.trap_expected = 0;
4674 fprintf_unfiltered (gdb_stdlog,
4675 "infrun: switching back to stepped thread\n");
4677 ecs->event_thread = tp;
4678 ecs->ptid = tp->ptid;
4679 context_switch (ecs->ptid);
4685 if (ecs->event_thread->control.step_resume_breakpoint)
4688 fprintf_unfiltered (gdb_stdlog,
4689 "infrun: step-resume breakpoint is inserted\n");
4691 /* Having a step-resume breakpoint overrides anything
4692 else having to do with stepping commands until
4693 that breakpoint is reached. */
4698 if (ecs->event_thread->control.step_range_end == 0)
4701 fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n");
4702 /* Likewise if we aren't even stepping. */
4707 /* Re-fetch current thread's frame in case the code above caused
4708 the frame cache to be re-initialized, making our FRAME variable
4709 a dangling pointer. */
4710 frame = get_current_frame ();
4711 gdbarch = get_frame_arch (frame);
4712 fill_in_stop_func (gdbarch, ecs);
4714 /* If stepping through a line, keep going if still within it.
4716 Note that step_range_end is the address of the first instruction
4717 beyond the step range, and NOT the address of the last instruction
4720 Note also that during reverse execution, we may be stepping
4721 through a function epilogue and therefore must detect when
4722 the current-frame changes in the middle of a line. */
4724 if (pc_in_thread_step_range (stop_pc, ecs->event_thread)
4725 && (execution_direction != EXEC_REVERSE
4726 || frame_id_eq (get_frame_id (frame),
4727 ecs->event_thread->control.step_frame_id)))
4731 (gdb_stdlog, "infrun: stepping inside range [%s-%s]\n",
4732 paddress (gdbarch, ecs->event_thread->control.step_range_start),
4733 paddress (gdbarch, ecs->event_thread->control.step_range_end));
4735 /* Tentatively re-enable range stepping; `resume' disables it if
4736 necessary (e.g., if we're stepping over a breakpoint or we
4737 have software watchpoints). */
4738 ecs->event_thread->control.may_range_step = 1;
4740 /* When stepping backward, stop at beginning of line range
4741 (unless it's the function entry point, in which case
4742 keep going back to the call point). */
4743 if (stop_pc == ecs->event_thread->control.step_range_start
4744 && stop_pc != ecs->stop_func_start
4745 && execution_direction == EXEC_REVERSE)
4747 ecs->event_thread->control.stop_step = 1;
4748 print_end_stepping_range_reason ();
4749 stop_stepping (ecs);
4757 /* We stepped out of the stepping range. */
4759 /* If we are stepping at the source level and entered the runtime
4760 loader dynamic symbol resolution code...
4762 EXEC_FORWARD: we keep on single stepping until we exit the run
4763 time loader code and reach the callee's address.
4765 EXEC_REVERSE: we've already executed the callee (backward), and
4766 the runtime loader code is handled just like any other
4767 undebuggable function call. Now we need only keep stepping
4768 backward through the trampoline code, and that's handled further
4769 down, so there is nothing for us to do here. */
4771 if (execution_direction != EXEC_REVERSE
4772 && ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
4773 && in_solib_dynsym_resolve_code (stop_pc))
4775 CORE_ADDR pc_after_resolver =
4776 gdbarch_skip_solib_resolver (gdbarch, stop_pc);
4779 fprintf_unfiltered (gdb_stdlog,
4780 "infrun: stepped into dynsym resolve code\n");
4782 if (pc_after_resolver)
4784 /* Set up a step-resume breakpoint at the address
4785 indicated by SKIP_SOLIB_RESOLVER. */
4786 struct symtab_and_line sr_sal;
4789 sr_sal.pc = pc_after_resolver;
4790 sr_sal.pspace = get_frame_program_space (frame);
4792 insert_step_resume_breakpoint_at_sal (gdbarch,
4793 sr_sal, null_frame_id);
4800 if (ecs->event_thread->control.step_range_end != 1
4801 && (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
4802 || ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
4803 && get_frame_type (frame) == SIGTRAMP_FRAME)
4806 fprintf_unfiltered (gdb_stdlog,
4807 "infrun: stepped into signal trampoline\n");
4808 /* The inferior, while doing a "step" or "next", has ended up in
4809 a signal trampoline (either by a signal being delivered or by
4810 the signal handler returning). Just single-step until the
4811 inferior leaves the trampoline (either by calling the handler
4817 /* If we're in the return path from a shared library trampoline,
4818 we want to proceed through the trampoline when stepping. */
4819 /* macro/2012-04-25: This needs to come before the subroutine
4820 call check below as on some targets return trampolines look
4821 like subroutine calls (MIPS16 return thunks). */
4822 if (gdbarch_in_solib_return_trampoline (gdbarch,
4823 stop_pc, ecs->stop_func_name)
4824 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
4826 /* Determine where this trampoline returns. */
4827 CORE_ADDR real_stop_pc;
4829 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
4832 fprintf_unfiltered (gdb_stdlog,
4833 "infrun: stepped into solib return tramp\n");
4835 /* Only proceed through if we know where it's going. */
4838 /* And put the step-breakpoint there and go until there. */
4839 struct symtab_and_line sr_sal;
4841 init_sal (&sr_sal); /* initialize to zeroes */
4842 sr_sal.pc = real_stop_pc;
4843 sr_sal.section = find_pc_overlay (sr_sal.pc);
4844 sr_sal.pspace = get_frame_program_space (frame);
4846 /* Do not specify what the fp should be when we stop since
4847 on some machines the prologue is where the new fp value
4849 insert_step_resume_breakpoint_at_sal (gdbarch,
4850 sr_sal, null_frame_id);
4852 /* Restart without fiddling with the step ranges or
4859 /* Check for subroutine calls. The check for the current frame
4860 equalling the step ID is not necessary - the check of the
4861 previous frame's ID is sufficient - but it is a common case and
4862 cheaper than checking the previous frame's ID.
4864 NOTE: frame_id_eq will never report two invalid frame IDs as
4865 being equal, so to get into this block, both the current and
4866 previous frame must have valid frame IDs. */
4867 /* The outer_frame_id check is a heuristic to detect stepping
4868 through startup code. If we step over an instruction which
4869 sets the stack pointer from an invalid value to a valid value,
4870 we may detect that as a subroutine call from the mythical
4871 "outermost" function. This could be fixed by marking
4872 outermost frames as !stack_p,code_p,special_p. Then the
4873 initial outermost frame, before sp was valid, would
4874 have code_addr == &_start. See the comment in frame_id_eq
4876 if (!frame_id_eq (get_stack_frame_id (frame),
4877 ecs->event_thread->control.step_stack_frame_id)
4878 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4879 ecs->event_thread->control.step_stack_frame_id)
4880 && (!frame_id_eq (ecs->event_thread->control.step_stack_frame_id,
4882 || step_start_function != find_pc_function (stop_pc))))
4884 CORE_ADDR real_stop_pc;
4887 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n");
4889 if ((ecs->event_thread->control.step_over_calls == STEP_OVER_NONE)
4890 || ((ecs->event_thread->control.step_range_end == 1)
4891 && in_prologue (gdbarch, ecs->event_thread->prev_pc,
4892 ecs->stop_func_start)))
4894 /* I presume that step_over_calls is only 0 when we're
4895 supposed to be stepping at the assembly language level
4896 ("stepi"). Just stop. */
4897 /* Also, maybe we just did a "nexti" inside a prolog, so we
4898 thought it was a subroutine call but it was not. Stop as
4900 /* And this works the same backward as frontward. MVS */
4901 ecs->event_thread->control.stop_step = 1;
4902 print_end_stepping_range_reason ();
4903 stop_stepping (ecs);
4907 /* Reverse stepping through solib trampolines. */
4909 if (execution_direction == EXEC_REVERSE
4910 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE
4911 && (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
4924 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
4926 /* We're doing a "next".
4928 Normal (forward) execution: set a breakpoint at the
4929 callee's return address (the address at which the caller
4932 Reverse (backward) execution. set the step-resume
4933 breakpoint at the start of the function that we just
4934 stepped into (backwards), and continue to there. When we
4935 get there, we'll need to single-step back to the caller. */
4937 if (execution_direction == EXEC_REVERSE)
4939 /* If we're already at the start of the function, we've either
4940 just stepped backward into a single instruction function,
4941 or stepped back out of a signal handler to the first instruction
4942 of the function. Just keep going, which will single-step back
4944 if (ecs->stop_func_start != stop_pc)
4946 struct symtab_and_line sr_sal;
4948 /* Normal function call return (static or dynamic). */
4950 sr_sal.pc = ecs->stop_func_start;
4951 sr_sal.pspace = get_frame_program_space (frame);
4952 insert_step_resume_breakpoint_at_sal (gdbarch,
4953 sr_sal, null_frame_id);
4957 insert_step_resume_breakpoint_at_caller (frame);
4963 /* If we are in a function call trampoline (a stub between the
4964 calling routine and the real function), locate the real
4965 function. That's what tells us (a) whether we want to step
4966 into it at all, and (b) what prologue we want to run to the
4967 end of, if we do step into it. */
4968 real_stop_pc = skip_language_trampoline (frame, stop_pc);
4969 if (real_stop_pc == 0)
4970 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
4971 if (real_stop_pc != 0)
4972 ecs->stop_func_start = real_stop_pc;
4974 if (real_stop_pc != 0 && in_solib_dynsym_resolve_code (real_stop_pc))
4976 struct symtab_and_line sr_sal;
4979 sr_sal.pc = ecs->stop_func_start;
4980 sr_sal.pspace = get_frame_program_space (frame);
4982 insert_step_resume_breakpoint_at_sal (gdbarch,
4983 sr_sal, null_frame_id);
4988 /* If we have line number information for the function we are
4989 thinking of stepping into and the function isn't on the skip
4992 If there are several symtabs at that PC (e.g. with include
4993 files), just want to know whether *any* of them have line
4994 numbers. find_pc_line handles this. */
4996 struct symtab_and_line tmp_sal;
4998 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
4999 if (tmp_sal.line != 0
5000 && !function_name_is_marked_for_skip (ecs->stop_func_name,
5003 if (execution_direction == EXEC_REVERSE)
5004 handle_step_into_function_backward (gdbarch, ecs);
5006 handle_step_into_function (gdbarch, ecs);
5011 /* If we have no line number and the step-stop-if-no-debug is
5012 set, we stop the step so that the user has a chance to switch
5013 in assembly mode. */
5014 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
5015 && step_stop_if_no_debug)
5017 ecs->event_thread->control.stop_step = 1;
5018 print_end_stepping_range_reason ();
5019 stop_stepping (ecs);
5023 if (execution_direction == EXEC_REVERSE)
5025 /* If we're already at the start of the function, we've either just
5026 stepped backward into a single instruction function without line
5027 number info, or stepped back out of a signal handler to the first
5028 instruction of the function without line number info. Just keep
5029 going, which will single-step back to the caller. */
5030 if (ecs->stop_func_start != stop_pc)
5032 /* Set a breakpoint at callee's start address.
5033 From there we can step once and be back in the caller. */
5034 struct symtab_and_line sr_sal;
5037 sr_sal.pc = ecs->stop_func_start;
5038 sr_sal.pspace = get_frame_program_space (frame);
5039 insert_step_resume_breakpoint_at_sal (gdbarch,
5040 sr_sal, null_frame_id);
5044 /* Set a breakpoint at callee's return address (the address
5045 at which the caller will resume). */
5046 insert_step_resume_breakpoint_at_caller (frame);
5052 /* Reverse stepping through solib trampolines. */
5054 if (execution_direction == EXEC_REVERSE
5055 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
5057 if (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
5058 || (ecs->stop_func_start == 0
5059 && in_solib_dynsym_resolve_code (stop_pc)))
5061 /* Any solib trampoline code can be handled in reverse
5062 by simply continuing to single-step. We have already
5063 executed the solib function (backwards), and a few
5064 steps will take us back through the trampoline to the
5069 else if (in_solib_dynsym_resolve_code (stop_pc))
5071 /* Stepped backward into the solib dynsym resolver.
5072 Set a breakpoint at its start and continue, then
5073 one more step will take us out. */
5074 struct symtab_and_line sr_sal;
5077 sr_sal.pc = ecs->stop_func_start;
5078 sr_sal.pspace = get_frame_program_space (frame);
5079 insert_step_resume_breakpoint_at_sal (gdbarch,
5080 sr_sal, null_frame_id);
5086 stop_pc_sal = find_pc_line (stop_pc, 0);
5088 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5089 the trampoline processing logic, however, there are some trampolines
5090 that have no names, so we should do trampoline handling first. */
5091 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
5092 && ecs->stop_func_name == NULL
5093 && stop_pc_sal.line == 0)
5096 fprintf_unfiltered (gdb_stdlog,
5097 "infrun: stepped into undebuggable function\n");
5099 /* The inferior just stepped into, or returned to, an
5100 undebuggable function (where there is no debugging information
5101 and no line number corresponding to the address where the
5102 inferior stopped). Since we want to skip this kind of code,
5103 we keep going until the inferior returns from this
5104 function - unless the user has asked us not to (via
5105 set step-mode) or we no longer know how to get back
5106 to the call site. */
5107 if (step_stop_if_no_debug
5108 || !frame_id_p (frame_unwind_caller_id (frame)))
5110 /* If we have no line number and the step-stop-if-no-debug
5111 is set, we stop the step so that the user has a chance to
5112 switch in assembly mode. */
5113 ecs->event_thread->control.stop_step = 1;
5114 print_end_stepping_range_reason ();
5115 stop_stepping (ecs);
5120 /* Set a breakpoint at callee's return address (the address
5121 at which the caller will resume). */
5122 insert_step_resume_breakpoint_at_caller (frame);
5128 if (ecs->event_thread->control.step_range_end == 1)
5130 /* It is stepi or nexti. We always want to stop stepping after
5133 fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
5134 ecs->event_thread->control.stop_step = 1;
5135 print_end_stepping_range_reason ();
5136 stop_stepping (ecs);
5140 if (stop_pc_sal.line == 0)
5142 /* We have no line number information. That means to stop
5143 stepping (does this always happen right after one instruction,
5144 when we do "s" in a function with no line numbers,
5145 or can this happen as a result of a return or longjmp?). */
5147 fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n");
5148 ecs->event_thread->control.stop_step = 1;
5149 print_end_stepping_range_reason ();
5150 stop_stepping (ecs);
5154 /* Look for "calls" to inlined functions, part one. If the inline
5155 frame machinery detected some skipped call sites, we have entered
5156 a new inline function. */
5158 if (frame_id_eq (get_frame_id (get_current_frame ()),
5159 ecs->event_thread->control.step_frame_id)
5160 && inline_skipped_frames (ecs->ptid))
5162 struct symtab_and_line call_sal;
5165 fprintf_unfiltered (gdb_stdlog,
5166 "infrun: stepped into inlined function\n");
5168 find_frame_sal (get_current_frame (), &call_sal);
5170 if (ecs->event_thread->control.step_over_calls != STEP_OVER_ALL)
5172 /* For "step", we're going to stop. But if the call site
5173 for this inlined function is on the same source line as
5174 we were previously stepping, go down into the function
5175 first. Otherwise stop at the call site. */
5177 if (call_sal.line == ecs->event_thread->current_line
5178 && call_sal.symtab == ecs->event_thread->current_symtab)
5179 step_into_inline_frame (ecs->ptid);
5181 ecs->event_thread->control.stop_step = 1;
5182 print_end_stepping_range_reason ();
5183 stop_stepping (ecs);
5188 /* For "next", we should stop at the call site if it is on a
5189 different source line. Otherwise continue through the
5190 inlined function. */
5191 if (call_sal.line == ecs->event_thread->current_line
5192 && call_sal.symtab == ecs->event_thread->current_symtab)
5196 ecs->event_thread->control.stop_step = 1;
5197 print_end_stepping_range_reason ();
5198 stop_stepping (ecs);
5204 /* Look for "calls" to inlined functions, part two. If we are still
5205 in the same real function we were stepping through, but we have
5206 to go further up to find the exact frame ID, we are stepping
5207 through a more inlined call beyond its call site. */
5209 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5210 && !frame_id_eq (get_frame_id (get_current_frame ()),
5211 ecs->event_thread->control.step_frame_id)
5212 && stepped_in_from (get_current_frame (),
5213 ecs->event_thread->control.step_frame_id))
5216 fprintf_unfiltered (gdb_stdlog,
5217 "infrun: stepping through inlined function\n");
5219 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
5223 ecs->event_thread->control.stop_step = 1;
5224 print_end_stepping_range_reason ();
5225 stop_stepping (ecs);
5230 if ((stop_pc == stop_pc_sal.pc)
5231 && (ecs->event_thread->current_line != stop_pc_sal.line
5232 || ecs->event_thread->current_symtab != stop_pc_sal.symtab))
5234 /* We are at the start of a different line. So stop. Note that
5235 we don't stop if we step into the middle of a different line.
5236 That is said to make things like for (;;) statements work
5239 fprintf_unfiltered (gdb_stdlog,
5240 "infrun: stepped to a different line\n");
5241 ecs->event_thread->control.stop_step = 1;
5242 print_end_stepping_range_reason ();
5243 stop_stepping (ecs);
5247 /* We aren't done stepping.
5249 Optimize by setting the stepping range to the line.
5250 (We might not be in the original line, but if we entered a
5251 new line in mid-statement, we continue stepping. This makes
5252 things like for(;;) statements work better.) */
5254 ecs->event_thread->control.step_range_start = stop_pc_sal.pc;
5255 ecs->event_thread->control.step_range_end = stop_pc_sal.end;
5256 ecs->event_thread->control.may_range_step = 1;
5257 set_step_info (frame, stop_pc_sal);
5260 fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n");
5264 /* Is thread TP in the middle of single-stepping? */
5267 currently_stepping (struct thread_info *tp)
5269 return ((tp->control.step_range_end
5270 && tp->control.step_resume_breakpoint == NULL)
5271 || tp->control.trap_expected
5272 || bpstat_should_step ());
5275 /* Returns true if any thread *but* the one passed in "data" is in the
5276 middle of stepping or of handling a "next". */
5279 currently_stepping_or_nexting_callback (struct thread_info *tp, void *data)
5284 return (tp->control.step_range_end
5285 || tp->control.trap_expected);
5288 /* Inferior has stepped into a subroutine call with source code that
5289 we should not step over. Do step to the first line of code in
5293 handle_step_into_function (struct gdbarch *gdbarch,
5294 struct execution_control_state *ecs)
5297 struct symtab_and_line stop_func_sal, sr_sal;
5299 fill_in_stop_func (gdbarch, ecs);
5301 s = find_pc_symtab (stop_pc);
5302 if (s && s->language != language_asm)
5303 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
5304 ecs->stop_func_start);
5306 stop_func_sal = find_pc_line (ecs->stop_func_start, 0);
5307 /* Use the step_resume_break to step until the end of the prologue,
5308 even if that involves jumps (as it seems to on the vax under
5310 /* If the prologue ends in the middle of a source line, continue to
5311 the end of that source line (if it is still within the function).
5312 Otherwise, just go to end of prologue. */
5313 if (stop_func_sal.end
5314 && stop_func_sal.pc != ecs->stop_func_start
5315 && stop_func_sal.end < ecs->stop_func_end)
5316 ecs->stop_func_start = stop_func_sal.end;
5318 /* Architectures which require breakpoint adjustment might not be able
5319 to place a breakpoint at the computed address. If so, the test
5320 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5321 ecs->stop_func_start to an address at which a breakpoint may be
5322 legitimately placed.
5324 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5325 made, GDB will enter an infinite loop when stepping through
5326 optimized code consisting of VLIW instructions which contain
5327 subinstructions corresponding to different source lines. On
5328 FR-V, it's not permitted to place a breakpoint on any but the
5329 first subinstruction of a VLIW instruction. When a breakpoint is
5330 set, GDB will adjust the breakpoint address to the beginning of
5331 the VLIW instruction. Thus, we need to make the corresponding
5332 adjustment here when computing the stop address. */
5334 if (gdbarch_adjust_breakpoint_address_p (gdbarch))
5336 ecs->stop_func_start
5337 = gdbarch_adjust_breakpoint_address (gdbarch,
5338 ecs->stop_func_start);
5341 if (ecs->stop_func_start == stop_pc)
5343 /* We are already there: stop now. */
5344 ecs->event_thread->control.stop_step = 1;
5345 print_end_stepping_range_reason ();
5346 stop_stepping (ecs);
5351 /* Put the step-breakpoint there and go until there. */
5352 init_sal (&sr_sal); /* initialize to zeroes */
5353 sr_sal.pc = ecs->stop_func_start;
5354 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
5355 sr_sal.pspace = get_frame_program_space (get_current_frame ());
5357 /* Do not specify what the fp should be when we stop since on
5358 some machines the prologue is where the new fp value is
5360 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal, null_frame_id);
5362 /* And make sure stepping stops right away then. */
5363 ecs->event_thread->control.step_range_end
5364 = ecs->event_thread->control.step_range_start;
5369 /* Inferior has stepped backward into a subroutine call with source
5370 code that we should not step over. Do step to the beginning of the
5371 last line of code in it. */
5374 handle_step_into_function_backward (struct gdbarch *gdbarch,
5375 struct execution_control_state *ecs)
5378 struct symtab_and_line stop_func_sal;
5380 fill_in_stop_func (gdbarch, ecs);
5382 s = find_pc_symtab (stop_pc);
5383 if (s && s->language != language_asm)
5384 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
5385 ecs->stop_func_start);
5387 stop_func_sal = find_pc_line (stop_pc, 0);
5389 /* OK, we're just going to keep stepping here. */
5390 if (stop_func_sal.pc == stop_pc)
5392 /* We're there already. Just stop stepping now. */
5393 ecs->event_thread->control.stop_step = 1;
5394 print_end_stepping_range_reason ();
5395 stop_stepping (ecs);
5399 /* Else just reset the step range and keep going.
5400 No step-resume breakpoint, they don't work for
5401 epilogues, which can have multiple entry paths. */
5402 ecs->event_thread->control.step_range_start = stop_func_sal.pc;
5403 ecs->event_thread->control.step_range_end = stop_func_sal.end;
5409 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5410 This is used to both functions and to skip over code. */
5413 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch *gdbarch,
5414 struct symtab_and_line sr_sal,
5415 struct frame_id sr_id,
5416 enum bptype sr_type)
5418 /* There should never be more than one step-resume or longjmp-resume
5419 breakpoint per thread, so we should never be setting a new
5420 step_resume_breakpoint when one is already active. */
5421 gdb_assert (inferior_thread ()->control.step_resume_breakpoint == NULL);
5422 gdb_assert (sr_type == bp_step_resume || sr_type == bp_hp_step_resume);
5425 fprintf_unfiltered (gdb_stdlog,
5426 "infrun: inserting step-resume breakpoint at %s\n",
5427 paddress (gdbarch, sr_sal.pc));
5429 inferior_thread ()->control.step_resume_breakpoint
5430 = set_momentary_breakpoint (gdbarch, sr_sal, sr_id, sr_type);
5434 insert_step_resume_breakpoint_at_sal (struct gdbarch *gdbarch,
5435 struct symtab_and_line sr_sal,
5436 struct frame_id sr_id)
5438 insert_step_resume_breakpoint_at_sal_1 (gdbarch,
5443 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5444 This is used to skip a potential signal handler.
5446 This is called with the interrupted function's frame. The signal
5447 handler, when it returns, will resume the interrupted function at
5451 insert_hp_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
5453 struct symtab_and_line sr_sal;
5454 struct gdbarch *gdbarch;
5456 gdb_assert (return_frame != NULL);
5457 init_sal (&sr_sal); /* initialize to zeros */
5459 gdbarch = get_frame_arch (return_frame);
5460 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch, get_frame_pc (return_frame));
5461 sr_sal.section = find_pc_overlay (sr_sal.pc);
5462 sr_sal.pspace = get_frame_program_space (return_frame);
5464 insert_step_resume_breakpoint_at_sal_1 (gdbarch, sr_sal,
5465 get_stack_frame_id (return_frame),
5469 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5470 is used to skip a function after stepping into it (for "next" or if
5471 the called function has no debugging information).
5473 The current function has almost always been reached by single
5474 stepping a call or return instruction. NEXT_FRAME belongs to the
5475 current function, and the breakpoint will be set at the caller's
5478 This is a separate function rather than reusing
5479 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5480 get_prev_frame, which may stop prematurely (see the implementation
5481 of frame_unwind_caller_id for an example). */
5484 insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame)
5486 struct symtab_and_line sr_sal;
5487 struct gdbarch *gdbarch;
5489 /* We shouldn't have gotten here if we don't know where the call site
5491 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame)));
5493 init_sal (&sr_sal); /* initialize to zeros */
5495 gdbarch = frame_unwind_caller_arch (next_frame);
5496 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch,
5497 frame_unwind_caller_pc (next_frame));
5498 sr_sal.section = find_pc_overlay (sr_sal.pc);
5499 sr_sal.pspace = frame_unwind_program_space (next_frame);
5501 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal,
5502 frame_unwind_caller_id (next_frame));
5505 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5506 new breakpoint at the target of a jmp_buf. The handling of
5507 longjmp-resume uses the same mechanisms used for handling
5508 "step-resume" breakpoints. */
5511 insert_longjmp_resume_breakpoint (struct gdbarch *gdbarch, CORE_ADDR pc)
5513 /* There should never be more than one longjmp-resume breakpoint per
5514 thread, so we should never be setting a new
5515 longjmp_resume_breakpoint when one is already active. */
5516 gdb_assert (inferior_thread ()->control.exception_resume_breakpoint == NULL);
5519 fprintf_unfiltered (gdb_stdlog,
5520 "infrun: inserting longjmp-resume breakpoint at %s\n",
5521 paddress (gdbarch, pc));
5523 inferior_thread ()->control.exception_resume_breakpoint =
5524 set_momentary_breakpoint_at_pc (gdbarch, pc, bp_longjmp_resume);
5527 /* Insert an exception resume breakpoint. TP is the thread throwing
5528 the exception. The block B is the block of the unwinder debug hook
5529 function. FRAME is the frame corresponding to the call to this
5530 function. SYM is the symbol of the function argument holding the
5531 target PC of the exception. */
5534 insert_exception_resume_breakpoint (struct thread_info *tp,
5536 struct frame_info *frame,
5539 volatile struct gdb_exception e;
5541 /* We want to ignore errors here. */
5542 TRY_CATCH (e, RETURN_MASK_ERROR)
5544 struct symbol *vsym;
5545 struct value *value;
5547 struct breakpoint *bp;
5549 vsym = lookup_symbol (SYMBOL_LINKAGE_NAME (sym), b, VAR_DOMAIN, NULL);
5550 value = read_var_value (vsym, frame);
5551 /* If the value was optimized out, revert to the old behavior. */
5552 if (! value_optimized_out (value))
5554 handler = value_as_address (value);
5557 fprintf_unfiltered (gdb_stdlog,
5558 "infrun: exception resume at %lx\n",
5559 (unsigned long) handler);
5561 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
5562 handler, bp_exception_resume);
5564 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5567 bp->thread = tp->num;
5568 inferior_thread ()->control.exception_resume_breakpoint = bp;
5573 /* A helper for check_exception_resume that sets an
5574 exception-breakpoint based on a SystemTap probe. */
5577 insert_exception_resume_from_probe (struct thread_info *tp,
5578 const struct probe *probe,
5579 struct frame_info *frame)
5581 struct value *arg_value;
5583 struct breakpoint *bp;
5585 arg_value = probe_safe_evaluate_at_pc (frame, 1);
5589 handler = value_as_address (arg_value);
5592 fprintf_unfiltered (gdb_stdlog,
5593 "infrun: exception resume at %s\n",
5594 paddress (get_objfile_arch (probe->objfile),
5597 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
5598 handler, bp_exception_resume);
5599 bp->thread = tp->num;
5600 inferior_thread ()->control.exception_resume_breakpoint = bp;
5603 /* This is called when an exception has been intercepted. Check to
5604 see whether the exception's destination is of interest, and if so,
5605 set an exception resume breakpoint there. */
5608 check_exception_resume (struct execution_control_state *ecs,
5609 struct frame_info *frame)
5611 volatile struct gdb_exception e;
5612 const struct probe *probe;
5613 struct symbol *func;
5615 /* First see if this exception unwinding breakpoint was set via a
5616 SystemTap probe point. If so, the probe has two arguments: the
5617 CFA and the HANDLER. We ignore the CFA, extract the handler, and
5618 set a breakpoint there. */
5619 probe = find_probe_by_pc (get_frame_pc (frame));
5622 insert_exception_resume_from_probe (ecs->event_thread, probe, frame);
5626 func = get_frame_function (frame);
5630 TRY_CATCH (e, RETURN_MASK_ERROR)
5633 struct block_iterator iter;
5637 /* The exception breakpoint is a thread-specific breakpoint on
5638 the unwinder's debug hook, declared as:
5640 void _Unwind_DebugHook (void *cfa, void *handler);
5642 The CFA argument indicates the frame to which control is
5643 about to be transferred. HANDLER is the destination PC.
5645 We ignore the CFA and set a temporary breakpoint at HANDLER.
5646 This is not extremely efficient but it avoids issues in gdb
5647 with computing the DWARF CFA, and it also works even in weird
5648 cases such as throwing an exception from inside a signal
5651 b = SYMBOL_BLOCK_VALUE (func);
5652 ALL_BLOCK_SYMBOLS (b, iter, sym)
5654 if (!SYMBOL_IS_ARGUMENT (sym))
5661 insert_exception_resume_breakpoint (ecs->event_thread,
5670 stop_stepping (struct execution_control_state *ecs)
5673 fprintf_unfiltered (gdb_stdlog, "infrun: stop_stepping\n");
5675 /* Let callers know we don't want to wait for the inferior anymore. */
5676 ecs->wait_some_more = 0;
5679 /* This function handles various cases where we need to continue
5680 waiting for the inferior. */
5681 /* (Used to be the keep_going: label in the old wait_for_inferior). */
5684 keep_going (struct execution_control_state *ecs)
5686 /* Make sure normal_stop is called if we get a QUIT handled before
5688 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
5690 /* Save the pc before execution, to compare with pc after stop. */
5691 ecs->event_thread->prev_pc
5692 = regcache_read_pc (get_thread_regcache (ecs->ptid));
5694 /* If we did not do break;, it means we should keep running the
5695 inferior and not return to debugger. */
5697 if (ecs->event_thread->control.trap_expected
5698 && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_TRAP)
5700 /* We took a signal (which we are supposed to pass through to
5701 the inferior, else we'd not get here) and we haven't yet
5702 gotten our trap. Simply continue. */
5704 discard_cleanups (old_cleanups);
5705 resume (currently_stepping (ecs->event_thread),
5706 ecs->event_thread->suspend.stop_signal);
5710 /* Either the trap was not expected, but we are continuing
5711 anyway (the user asked that this signal be passed to the
5714 The signal was SIGTRAP, e.g. it was our signal, but we
5715 decided we should resume from it.
5717 We're going to run this baby now!
5719 Note that insert_breakpoints won't try to re-insert
5720 already inserted breakpoints. Therefore, we don't
5721 care if breakpoints were already inserted, or not. */
5723 if (ecs->event_thread->stepping_over_breakpoint)
5725 struct regcache *thread_regcache = get_thread_regcache (ecs->ptid);
5727 if (!use_displaced_stepping (get_regcache_arch (thread_regcache)))
5728 /* Since we can't do a displaced step, we have to remove
5729 the breakpoint while we step it. To keep things
5730 simple, we remove them all. */
5731 remove_breakpoints ();
5735 volatile struct gdb_exception e;
5737 /* Stop stepping when inserting breakpoints
5739 TRY_CATCH (e, RETURN_MASK_ERROR)
5741 insert_breakpoints ();
5745 exception_print (gdb_stderr, e);
5746 stop_stepping (ecs);
5751 ecs->event_thread->control.trap_expected
5752 = ecs->event_thread->stepping_over_breakpoint;
5754 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
5755 specifies that such a signal should be delivered to the
5758 Typically, this would occure when a user is debugging a
5759 target monitor on a simulator: the target monitor sets a
5760 breakpoint; the simulator encounters this break-point and
5761 halts the simulation handing control to GDB; GDB, noteing
5762 that the break-point isn't valid, returns control back to the
5763 simulator; the simulator then delivers the hardware
5764 equivalent of a SIGNAL_TRAP to the program being debugged. */
5766 if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
5767 && !signal_program[ecs->event_thread->suspend.stop_signal])
5768 ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
5770 discard_cleanups (old_cleanups);
5771 resume (currently_stepping (ecs->event_thread),
5772 ecs->event_thread->suspend.stop_signal);
5775 prepare_to_wait (ecs);
5778 /* This function normally comes after a resume, before
5779 handle_inferior_event exits. It takes care of any last bits of
5780 housekeeping, and sets the all-important wait_some_more flag. */
5783 prepare_to_wait (struct execution_control_state *ecs)
5786 fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n");
5788 /* This is the old end of the while loop. Let everybody know we
5789 want to wait for the inferior some more and get called again
5791 ecs->wait_some_more = 1;
5794 /* Several print_*_reason functions to print why the inferior has stopped.
5795 We always print something when the inferior exits, or receives a signal.
5796 The rest of the cases are dealt with later on in normal_stop and
5797 print_it_typical. Ideally there should be a call to one of these
5798 print_*_reason functions functions from handle_inferior_event each time
5799 stop_stepping is called. */
5801 /* Print why the inferior has stopped.
5802 We are done with a step/next/si/ni command, print why the inferior has
5803 stopped. For now print nothing. Print a message only if not in the middle
5804 of doing a "step n" operation for n > 1. */
5807 print_end_stepping_range_reason (void)
5809 if ((!inferior_thread ()->step_multi
5810 || !inferior_thread ()->control.stop_step)
5811 && ui_out_is_mi_like_p (current_uiout))
5812 ui_out_field_string (current_uiout, "reason",
5813 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE));
5816 /* The inferior was terminated by a signal, print why it stopped. */
5819 print_signal_exited_reason (enum gdb_signal siggnal)
5821 struct ui_out *uiout = current_uiout;
5823 annotate_signalled ();
5824 if (ui_out_is_mi_like_p (uiout))
5826 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED));
5827 ui_out_text (uiout, "\nProgram terminated with signal ");
5828 annotate_signal_name ();
5829 ui_out_field_string (uiout, "signal-name",
5830 gdb_signal_to_name (siggnal));
5831 annotate_signal_name_end ();
5832 ui_out_text (uiout, ", ");
5833 annotate_signal_string ();
5834 ui_out_field_string (uiout, "signal-meaning",
5835 gdb_signal_to_string (siggnal));
5836 annotate_signal_string_end ();
5837 ui_out_text (uiout, ".\n");
5838 ui_out_text (uiout, "The program no longer exists.\n");
5841 /* The inferior program is finished, print why it stopped. */
5844 print_exited_reason (int exitstatus)
5846 struct inferior *inf = current_inferior ();
5847 const char *pidstr = target_pid_to_str (pid_to_ptid (inf->pid));
5848 struct ui_out *uiout = current_uiout;
5850 annotate_exited (exitstatus);
5853 if (ui_out_is_mi_like_p (uiout))
5854 ui_out_field_string (uiout, "reason",
5855 async_reason_lookup (EXEC_ASYNC_EXITED));
5856 ui_out_text (uiout, "[Inferior ");
5857 ui_out_text (uiout, plongest (inf->num));
5858 ui_out_text (uiout, " (");
5859 ui_out_text (uiout, pidstr);
5860 ui_out_text (uiout, ") exited with code ");
5861 ui_out_field_fmt (uiout, "exit-code", "0%o", (unsigned int) exitstatus);
5862 ui_out_text (uiout, "]\n");
5866 if (ui_out_is_mi_like_p (uiout))
5868 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY));
5869 ui_out_text (uiout, "[Inferior ");
5870 ui_out_text (uiout, plongest (inf->num));
5871 ui_out_text (uiout, " (");
5872 ui_out_text (uiout, pidstr);
5873 ui_out_text (uiout, ") exited normally]\n");
5875 /* Support the --return-child-result option. */
5876 return_child_result_value = exitstatus;
5879 /* Signal received, print why the inferior has stopped. The signal table
5880 tells us to print about it. */
5883 print_signal_received_reason (enum gdb_signal siggnal)
5885 struct ui_out *uiout = current_uiout;
5889 if (siggnal == GDB_SIGNAL_0 && !ui_out_is_mi_like_p (uiout))
5891 struct thread_info *t = inferior_thread ();
5893 ui_out_text (uiout, "\n[");
5894 ui_out_field_string (uiout, "thread-name",
5895 target_pid_to_str (t->ptid));
5896 ui_out_field_fmt (uiout, "thread-id", "] #%d", t->num);
5897 ui_out_text (uiout, " stopped");
5901 ui_out_text (uiout, "\nProgram received signal ");
5902 annotate_signal_name ();
5903 if (ui_out_is_mi_like_p (uiout))
5905 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
5906 ui_out_field_string (uiout, "signal-name",
5907 gdb_signal_to_name (siggnal));
5908 annotate_signal_name_end ();
5909 ui_out_text (uiout, ", ");
5910 annotate_signal_string ();
5911 ui_out_field_string (uiout, "signal-meaning",
5912 gdb_signal_to_string (siggnal));
5913 annotate_signal_string_end ();
5915 ui_out_text (uiout, ".\n");
5918 /* Reverse execution: target ran out of history info, print why the inferior
5922 print_no_history_reason (void)
5924 ui_out_text (current_uiout, "\nNo more reverse-execution history.\n");
5927 /* Here to return control to GDB when the inferior stops for real.
5928 Print appropriate messages, remove breakpoints, give terminal our modes.
5930 STOP_PRINT_FRAME nonzero means print the executing frame
5931 (pc, function, args, file, line number and line text).
5932 BREAKPOINTS_FAILED nonzero means stop was due to error
5933 attempting to insert breakpoints. */
5938 struct target_waitstatus last;
5940 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
5942 get_last_target_status (&last_ptid, &last);
5944 /* If an exception is thrown from this point on, make sure to
5945 propagate GDB's knowledge of the executing state to the
5946 frontend/user running state. A QUIT is an easy exception to see
5947 here, so do this before any filtered output. */
5949 make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
5950 else if (last.kind != TARGET_WAITKIND_SIGNALLED
5951 && last.kind != TARGET_WAITKIND_EXITED
5952 && last.kind != TARGET_WAITKIND_NO_RESUMED)
5953 make_cleanup (finish_thread_state_cleanup, &inferior_ptid);
5955 /* In non-stop mode, we don't want GDB to switch threads behind the
5956 user's back, to avoid races where the user is typing a command to
5957 apply to thread x, but GDB switches to thread y before the user
5958 finishes entering the command. */
5960 /* As with the notification of thread events, we want to delay
5961 notifying the user that we've switched thread context until
5962 the inferior actually stops.
5964 There's no point in saying anything if the inferior has exited.
5965 Note that SIGNALLED here means "exited with a signal", not
5966 "received a signal". */
5968 && !ptid_equal (previous_inferior_ptid, inferior_ptid)
5969 && target_has_execution
5970 && last.kind != TARGET_WAITKIND_SIGNALLED
5971 && last.kind != TARGET_WAITKIND_EXITED
5972 && last.kind != TARGET_WAITKIND_NO_RESUMED)
5974 target_terminal_ours_for_output ();
5975 printf_filtered (_("[Switching to %s]\n"),
5976 target_pid_to_str (inferior_ptid));
5977 annotate_thread_changed ();
5978 previous_inferior_ptid = inferior_ptid;
5981 if (last.kind == TARGET_WAITKIND_NO_RESUMED)
5983 gdb_assert (sync_execution || !target_can_async_p ());
5985 target_terminal_ours_for_output ();
5986 printf_filtered (_("No unwaited-for children left.\n"));
5989 if (!breakpoints_always_inserted_mode () && target_has_execution)
5991 if (remove_breakpoints ())
5993 target_terminal_ours_for_output ();
5994 printf_filtered (_("Cannot remove breakpoints because "
5995 "program is no longer writable.\nFurther "
5996 "execution is probably impossible.\n"));
6000 /* If an auto-display called a function and that got a signal,
6001 delete that auto-display to avoid an infinite recursion. */
6003 if (stopped_by_random_signal)
6004 disable_current_display ();
6006 /* Don't print a message if in the middle of doing a "step n"
6007 operation for n > 1 */
6008 if (target_has_execution
6009 && last.kind != TARGET_WAITKIND_SIGNALLED
6010 && last.kind != TARGET_WAITKIND_EXITED
6011 && inferior_thread ()->step_multi
6012 && inferior_thread ()->control.stop_step)
6015 target_terminal_ours ();
6016 async_enable_stdin ();
6018 /* Set the current source location. This will also happen if we
6019 display the frame below, but the current SAL will be incorrect
6020 during a user hook-stop function. */
6021 if (has_stack_frames () && !stop_stack_dummy)
6022 set_current_sal_from_frame (get_current_frame (), 1);
6024 /* Let the user/frontend see the threads as stopped. */
6025 do_cleanups (old_chain);
6027 /* Look up the hook_stop and run it (CLI internally handles problem
6028 of stop_command's pre-hook not existing). */
6030 catch_errors (hook_stop_stub, stop_command,
6031 "Error while running hook_stop:\n", RETURN_MASK_ALL);
6033 if (!has_stack_frames ())
6036 if (last.kind == TARGET_WAITKIND_SIGNALLED
6037 || last.kind == TARGET_WAITKIND_EXITED)
6040 /* Select innermost stack frame - i.e., current frame is frame 0,
6041 and current location is based on that.
6042 Don't do this on return from a stack dummy routine,
6043 or if the program has exited. */
6045 if (!stop_stack_dummy)
6047 select_frame (get_current_frame ());
6049 /* Print current location without a level number, if
6050 we have changed functions or hit a breakpoint.
6051 Print source line if we have one.
6052 bpstat_print() contains the logic deciding in detail
6053 what to print, based on the event(s) that just occurred. */
6055 /* If --batch-silent is enabled then there's no need to print the current
6056 source location, and to try risks causing an error message about
6057 missing source files. */
6058 if (stop_print_frame && !batch_silent)
6062 int do_frame_printing = 1;
6063 struct thread_info *tp = inferior_thread ();
6065 bpstat_ret = bpstat_print (tp->control.stop_bpstat, last.kind);
6069 /* FIXME: cagney/2002-12-01: Given that a frame ID does
6070 (or should) carry around the function and does (or
6071 should) use that when doing a frame comparison. */
6072 if (tp->control.stop_step
6073 && frame_id_eq (tp->control.step_frame_id,
6074 get_frame_id (get_current_frame ()))
6075 && step_start_function == find_pc_function (stop_pc))
6076 source_flag = SRC_LINE; /* Finished step, just
6077 print source line. */
6079 source_flag = SRC_AND_LOC; /* Print location and
6082 case PRINT_SRC_AND_LOC:
6083 source_flag = SRC_AND_LOC; /* Print location and
6086 case PRINT_SRC_ONLY:
6087 source_flag = SRC_LINE;
6090 source_flag = SRC_LINE; /* something bogus */
6091 do_frame_printing = 0;
6094 internal_error (__FILE__, __LINE__, _("Unknown value."));
6097 /* The behavior of this routine with respect to the source
6099 SRC_LINE: Print only source line
6100 LOCATION: Print only location
6101 SRC_AND_LOC: Print location and source line. */
6102 if (do_frame_printing)
6103 print_stack_frame (get_selected_frame (NULL), 0, source_flag);
6105 /* Display the auto-display expressions. */
6110 /* Save the function value return registers, if we care.
6111 We might be about to restore their previous contents. */
6112 if (inferior_thread ()->control.proceed_to_finish
6113 && execution_direction != EXEC_REVERSE)
6115 /* This should not be necessary. */
6117 regcache_xfree (stop_registers);
6119 /* NB: The copy goes through to the target picking up the value of
6120 all the registers. */
6121 stop_registers = regcache_dup (get_current_regcache ());
6124 if (stop_stack_dummy == STOP_STACK_DUMMY)
6126 /* Pop the empty frame that contains the stack dummy.
6127 This also restores inferior state prior to the call
6128 (struct infcall_suspend_state). */
6129 struct frame_info *frame = get_current_frame ();
6131 gdb_assert (get_frame_type (frame) == DUMMY_FRAME);
6133 /* frame_pop() calls reinit_frame_cache as the last thing it
6134 does which means there's currently no selected frame. We
6135 don't need to re-establish a selected frame if the dummy call
6136 returns normally, that will be done by
6137 restore_infcall_control_state. However, we do have to handle
6138 the case where the dummy call is returning after being
6139 stopped (e.g. the dummy call previously hit a breakpoint).
6140 We can't know which case we have so just always re-establish
6141 a selected frame here. */
6142 select_frame (get_current_frame ());
6146 annotate_stopped ();
6148 /* Suppress the stop observer if we're in the middle of:
6150 - a step n (n > 1), as there still more steps to be done.
6152 - a "finish" command, as the observer will be called in
6153 finish_command_continuation, so it can include the inferior
6154 function's return value.
6156 - calling an inferior function, as we pretend we inferior didn't
6157 run at all. The return value of the call is handled by the
6158 expression evaluator, through call_function_by_hand. */
6160 if (!target_has_execution
6161 || last.kind == TARGET_WAITKIND_SIGNALLED
6162 || last.kind == TARGET_WAITKIND_EXITED
6163 || last.kind == TARGET_WAITKIND_NO_RESUMED
6164 || (!(inferior_thread ()->step_multi
6165 && inferior_thread ()->control.stop_step)
6166 && !(inferior_thread ()->control.stop_bpstat
6167 && inferior_thread ()->control.proceed_to_finish)
6168 && !inferior_thread ()->control.in_infcall))
6170 if (!ptid_equal (inferior_ptid, null_ptid))
6171 observer_notify_normal_stop (inferior_thread ()->control.stop_bpstat,
6174 observer_notify_normal_stop (NULL, stop_print_frame);
6177 if (target_has_execution)
6179 if (last.kind != TARGET_WAITKIND_SIGNALLED
6180 && last.kind != TARGET_WAITKIND_EXITED)
6181 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6182 Delete any breakpoint that is to be deleted at the next stop. */
6183 breakpoint_auto_delete (inferior_thread ()->control.stop_bpstat);
6186 /* Try to get rid of automatically added inferiors that are no
6187 longer needed. Keeping those around slows down things linearly.
6188 Note that this never removes the current inferior. */
6193 hook_stop_stub (void *cmd)
6195 execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
6200 signal_stop_state (int signo)
6202 return signal_stop[signo];
6206 signal_print_state (int signo)
6208 return signal_print[signo];
6212 signal_pass_state (int signo)
6214 return signal_program[signo];
6218 signal_cache_update (int signo)
6222 for (signo = 0; signo < (int) GDB_SIGNAL_LAST; signo++)
6223 signal_cache_update (signo);
6228 signal_pass[signo] = (signal_stop[signo] == 0
6229 && signal_print[signo] == 0
6230 && signal_program[signo] == 1
6231 && signal_catch[signo] == 0);
6235 signal_stop_update (int signo, int state)
6237 int ret = signal_stop[signo];
6239 signal_stop[signo] = state;
6240 signal_cache_update (signo);
6245 signal_print_update (int signo, int state)
6247 int ret = signal_print[signo];
6249 signal_print[signo] = state;
6250 signal_cache_update (signo);
6255 signal_pass_update (int signo, int state)
6257 int ret = signal_program[signo];
6259 signal_program[signo] = state;
6260 signal_cache_update (signo);
6264 /* Update the global 'signal_catch' from INFO and notify the
6268 signal_catch_update (const unsigned int *info)
6272 for (i = 0; i < GDB_SIGNAL_LAST; ++i)
6273 signal_catch[i] = info[i] > 0;
6274 signal_cache_update (-1);
6275 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
6279 sig_print_header (void)
6281 printf_filtered (_("Signal Stop\tPrint\tPass "
6282 "to program\tDescription\n"));
6286 sig_print_info (enum gdb_signal oursig)
6288 const char *name = gdb_signal_to_name (oursig);
6289 int name_padding = 13 - strlen (name);
6291 if (name_padding <= 0)
6294 printf_filtered ("%s", name);
6295 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
6296 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
6297 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
6298 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
6299 printf_filtered ("%s\n", gdb_signal_to_string (oursig));
6302 /* Specify how various signals in the inferior should be handled. */
6305 handle_command (char *args, int from_tty)
6308 int digits, wordlen;
6309 int sigfirst, signum, siglast;
6310 enum gdb_signal oursig;
6313 unsigned char *sigs;
6314 struct cleanup *old_chain;
6318 error_no_arg (_("signal to handle"));
6321 /* Allocate and zero an array of flags for which signals to handle. */
6323 nsigs = (int) GDB_SIGNAL_LAST;
6324 sigs = (unsigned char *) alloca (nsigs);
6325 memset (sigs, 0, nsigs);
6327 /* Break the command line up into args. */
6329 argv = gdb_buildargv (args);
6330 old_chain = make_cleanup_freeargv (argv);
6332 /* Walk through the args, looking for signal oursigs, signal names, and
6333 actions. Signal numbers and signal names may be interspersed with
6334 actions, with the actions being performed for all signals cumulatively
6335 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6337 while (*argv != NULL)
6339 wordlen = strlen (*argv);
6340 for (digits = 0; isdigit ((*argv)[digits]); digits++)
6344 sigfirst = siglast = -1;
6346 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
6348 /* Apply action to all signals except those used by the
6349 debugger. Silently skip those. */
6352 siglast = nsigs - 1;
6354 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
6356 SET_SIGS (nsigs, sigs, signal_stop);
6357 SET_SIGS (nsigs, sigs, signal_print);
6359 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
6361 UNSET_SIGS (nsigs, sigs, signal_program);
6363 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
6365 SET_SIGS (nsigs, sigs, signal_print);
6367 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
6369 SET_SIGS (nsigs, sigs, signal_program);
6371 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
6373 UNSET_SIGS (nsigs, sigs, signal_stop);
6375 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
6377 SET_SIGS (nsigs, sigs, signal_program);
6379 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
6381 UNSET_SIGS (nsigs, sigs, signal_print);
6382 UNSET_SIGS (nsigs, sigs, signal_stop);
6384 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
6386 UNSET_SIGS (nsigs, sigs, signal_program);
6388 else if (digits > 0)
6390 /* It is numeric. The numeric signal refers to our own
6391 internal signal numbering from target.h, not to host/target
6392 signal number. This is a feature; users really should be
6393 using symbolic names anyway, and the common ones like
6394 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6396 sigfirst = siglast = (int)
6397 gdb_signal_from_command (atoi (*argv));
6398 if ((*argv)[digits] == '-')
6401 gdb_signal_from_command (atoi ((*argv) + digits + 1));
6403 if (sigfirst > siglast)
6405 /* Bet he didn't figure we'd think of this case... */
6413 oursig = gdb_signal_from_name (*argv);
6414 if (oursig != GDB_SIGNAL_UNKNOWN)
6416 sigfirst = siglast = (int) oursig;
6420 /* Not a number and not a recognized flag word => complain. */
6421 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv);
6425 /* If any signal numbers or symbol names were found, set flags for
6426 which signals to apply actions to. */
6428 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
6430 switch ((enum gdb_signal) signum)
6432 case GDB_SIGNAL_TRAP:
6433 case GDB_SIGNAL_INT:
6434 if (!allsigs && !sigs[signum])
6436 if (query (_("%s is used by the debugger.\n\
6437 Are you sure you want to change it? "),
6438 gdb_signal_to_name ((enum gdb_signal) signum)))
6444 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6445 gdb_flush (gdb_stdout);
6450 case GDB_SIGNAL_DEFAULT:
6451 case GDB_SIGNAL_UNKNOWN:
6452 /* Make sure that "all" doesn't print these. */
6463 for (signum = 0; signum < nsigs; signum++)
6466 signal_cache_update (-1);
6467 target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
6468 target_program_signals ((int) GDB_SIGNAL_LAST, signal_program);
6472 /* Show the results. */
6473 sig_print_header ();
6474 for (; signum < nsigs; signum++)
6476 sig_print_info (signum);
6482 do_cleanups (old_chain);
6485 /* Complete the "handle" command. */
6487 static VEC (char_ptr) *
6488 handle_completer (struct cmd_list_element *ignore,
6489 const char *text, const char *word)
6491 VEC (char_ptr) *vec_signals, *vec_keywords, *return_val;
6492 static const char * const keywords[] =
6506 vec_signals = signal_completer (ignore, text, word);
6507 vec_keywords = complete_on_enum (keywords, word, word);
6509 return_val = VEC_merge (char_ptr, vec_signals, vec_keywords);
6510 VEC_free (char_ptr, vec_signals);
6511 VEC_free (char_ptr, vec_keywords);
6516 xdb_handle_command (char *args, int from_tty)
6519 struct cleanup *old_chain;
6522 error_no_arg (_("xdb command"));
6524 /* Break the command line up into args. */
6526 argv = gdb_buildargv (args);
6527 old_chain = make_cleanup_freeargv (argv);
6528 if (argv[1] != (char *) NULL)
6533 bufLen = strlen (argv[0]) + 20;
6534 argBuf = (char *) xmalloc (bufLen);
6538 enum gdb_signal oursig;
6540 oursig = gdb_signal_from_name (argv[0]);
6541 memset (argBuf, 0, bufLen);
6542 if (strcmp (argv[1], "Q") == 0)
6543 sprintf (argBuf, "%s %s", argv[0], "noprint");
6546 if (strcmp (argv[1], "s") == 0)
6548 if (!signal_stop[oursig])
6549 sprintf (argBuf, "%s %s", argv[0], "stop");
6551 sprintf (argBuf, "%s %s", argv[0], "nostop");
6553 else if (strcmp (argv[1], "i") == 0)
6555 if (!signal_program[oursig])
6556 sprintf (argBuf, "%s %s", argv[0], "pass");
6558 sprintf (argBuf, "%s %s", argv[0], "nopass");
6560 else if (strcmp (argv[1], "r") == 0)
6562 if (!signal_print[oursig])
6563 sprintf (argBuf, "%s %s", argv[0], "print");
6565 sprintf (argBuf, "%s %s", argv[0], "noprint");
6571 handle_command (argBuf, from_tty);
6573 printf_filtered (_("Invalid signal handling flag.\n"));
6578 do_cleanups (old_chain);
6582 gdb_signal_from_command (int num)
6584 if (num >= 1 && num <= 15)
6585 return (enum gdb_signal) num;
6586 error (_("Only signals 1-15 are valid as numeric signals.\n\
6587 Use \"info signals\" for a list of symbolic signals."));
6590 /* Print current contents of the tables set by the handle command.
6591 It is possible we should just be printing signals actually used
6592 by the current target (but for things to work right when switching
6593 targets, all signals should be in the signal tables). */
6596 signals_info (char *signum_exp, int from_tty)
6598 enum gdb_signal oursig;
6600 sig_print_header ();
6604 /* First see if this is a symbol name. */
6605 oursig = gdb_signal_from_name (signum_exp);
6606 if (oursig == GDB_SIGNAL_UNKNOWN)
6608 /* No, try numeric. */
6610 gdb_signal_from_command (parse_and_eval_long (signum_exp));
6612 sig_print_info (oursig);
6616 printf_filtered ("\n");
6617 /* These ugly casts brought to you by the native VAX compiler. */
6618 for (oursig = GDB_SIGNAL_FIRST;
6619 (int) oursig < (int) GDB_SIGNAL_LAST;
6620 oursig = (enum gdb_signal) ((int) oursig + 1))
6624 if (oursig != GDB_SIGNAL_UNKNOWN
6625 && oursig != GDB_SIGNAL_DEFAULT && oursig != GDB_SIGNAL_0)
6626 sig_print_info (oursig);
6629 printf_filtered (_("\nUse the \"handle\" command "
6630 "to change these tables.\n"));
6633 /* Check if it makes sense to read $_siginfo from the current thread
6634 at this point. If not, throw an error. */
6637 validate_siginfo_access (void)
6639 /* No current inferior, no siginfo. */
6640 if (ptid_equal (inferior_ptid, null_ptid))
6641 error (_("No thread selected."));
6643 /* Don't try to read from a dead thread. */
6644 if (is_exited (inferior_ptid))
6645 error (_("The current thread has terminated"));
6647 /* ... or from a spinning thread. */
6648 if (is_running (inferior_ptid))
6649 error (_("Selected thread is running."));
6652 /* The $_siginfo convenience variable is a bit special. We don't know
6653 for sure the type of the value until we actually have a chance to
6654 fetch the data. The type can change depending on gdbarch, so it is
6655 also dependent on which thread you have selected.
6657 1. making $_siginfo be an internalvar that creates a new value on
6660 2. making the value of $_siginfo be an lval_computed value. */
6662 /* This function implements the lval_computed support for reading a
6666 siginfo_value_read (struct value *v)
6668 LONGEST transferred;
6670 validate_siginfo_access ();
6673 target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO,
6675 value_contents_all_raw (v),
6677 TYPE_LENGTH (value_type (v)));
6679 if (transferred != TYPE_LENGTH (value_type (v)))
6680 error (_("Unable to read siginfo"));
6683 /* This function implements the lval_computed support for writing a
6687 siginfo_value_write (struct value *v, struct value *fromval)
6689 LONGEST transferred;
6691 validate_siginfo_access ();
6693 transferred = target_write (¤t_target,
6694 TARGET_OBJECT_SIGNAL_INFO,
6696 value_contents_all_raw (fromval),
6698 TYPE_LENGTH (value_type (fromval)));
6700 if (transferred != TYPE_LENGTH (value_type (fromval)))
6701 error (_("Unable to write siginfo"));
6704 static const struct lval_funcs siginfo_value_funcs =
6710 /* Return a new value with the correct type for the siginfo object of
6711 the current thread using architecture GDBARCH. Return a void value
6712 if there's no object available. */
6714 static struct value *
6715 siginfo_make_value (struct gdbarch *gdbarch, struct internalvar *var,
6718 if (target_has_stack
6719 && !ptid_equal (inferior_ptid, null_ptid)
6720 && gdbarch_get_siginfo_type_p (gdbarch))
6722 struct type *type = gdbarch_get_siginfo_type (gdbarch);
6724 return allocate_computed_value (type, &siginfo_value_funcs, NULL);
6727 return allocate_value (builtin_type (gdbarch)->builtin_void);
6731 /* infcall_suspend_state contains state about the program itself like its
6732 registers and any signal it received when it last stopped.
6733 This state must be restored regardless of how the inferior function call
6734 ends (either successfully, or after it hits a breakpoint or signal)
6735 if the program is to properly continue where it left off. */
6737 struct infcall_suspend_state
6739 struct thread_suspend_state thread_suspend;
6740 #if 0 /* Currently unused and empty structures are not valid C. */
6741 struct inferior_suspend_state inferior_suspend;
6746 struct regcache *registers;
6748 /* Format of SIGINFO_DATA or NULL if it is not present. */
6749 struct gdbarch *siginfo_gdbarch;
6751 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
6752 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
6753 content would be invalid. */
6754 gdb_byte *siginfo_data;
6757 struct infcall_suspend_state *
6758 save_infcall_suspend_state (void)
6760 struct infcall_suspend_state *inf_state;
6761 struct thread_info *tp = inferior_thread ();
6763 struct inferior *inf = current_inferior ();
6765 struct regcache *regcache = get_current_regcache ();
6766 struct gdbarch *gdbarch = get_regcache_arch (regcache);
6767 gdb_byte *siginfo_data = NULL;
6769 if (gdbarch_get_siginfo_type_p (gdbarch))
6771 struct type *type = gdbarch_get_siginfo_type (gdbarch);
6772 size_t len = TYPE_LENGTH (type);
6773 struct cleanup *back_to;
6775 siginfo_data = xmalloc (len);
6776 back_to = make_cleanup (xfree, siginfo_data);
6778 if (target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
6779 siginfo_data, 0, len) == len)
6780 discard_cleanups (back_to);
6783 /* Errors ignored. */
6784 do_cleanups (back_to);
6785 siginfo_data = NULL;
6789 inf_state = XZALLOC (struct infcall_suspend_state);
6793 inf_state->siginfo_gdbarch = gdbarch;
6794 inf_state->siginfo_data = siginfo_data;
6797 inf_state->thread_suspend = tp->suspend;
6798 #if 0 /* Currently unused and empty structures are not valid C. */
6799 inf_state->inferior_suspend = inf->suspend;
6802 /* run_inferior_call will not use the signal due to its `proceed' call with
6803 GDB_SIGNAL_0 anyway. */
6804 tp->suspend.stop_signal = GDB_SIGNAL_0;
6806 inf_state->stop_pc = stop_pc;
6808 inf_state->registers = regcache_dup (regcache);
6813 /* Restore inferior session state to INF_STATE. */
6816 restore_infcall_suspend_state (struct infcall_suspend_state *inf_state)
6818 struct thread_info *tp = inferior_thread ();
6820 struct inferior *inf = current_inferior ();
6822 struct regcache *regcache = get_current_regcache ();
6823 struct gdbarch *gdbarch = get_regcache_arch (regcache);
6825 tp->suspend = inf_state->thread_suspend;
6826 #if 0 /* Currently unused and empty structures are not valid C. */
6827 inf->suspend = inf_state->inferior_suspend;
6830 stop_pc = inf_state->stop_pc;
6832 if (inf_state->siginfo_gdbarch == gdbarch)
6834 struct type *type = gdbarch_get_siginfo_type (gdbarch);
6836 /* Errors ignored. */
6837 target_write (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
6838 inf_state->siginfo_data, 0, TYPE_LENGTH (type));
6841 /* The inferior can be gone if the user types "print exit(0)"
6842 (and perhaps other times). */
6843 if (target_has_execution)
6844 /* NB: The register write goes through to the target. */
6845 regcache_cpy (regcache, inf_state->registers);
6847 discard_infcall_suspend_state (inf_state);
6851 do_restore_infcall_suspend_state_cleanup (void *state)
6853 restore_infcall_suspend_state (state);
6857 make_cleanup_restore_infcall_suspend_state
6858 (struct infcall_suspend_state *inf_state)
6860 return make_cleanup (do_restore_infcall_suspend_state_cleanup, inf_state);
6864 discard_infcall_suspend_state (struct infcall_suspend_state *inf_state)
6866 regcache_xfree (inf_state->registers);
6867 xfree (inf_state->siginfo_data);
6872 get_infcall_suspend_state_regcache (struct infcall_suspend_state *inf_state)
6874 return inf_state->registers;
6877 /* infcall_control_state contains state regarding gdb's control of the
6878 inferior itself like stepping control. It also contains session state like
6879 the user's currently selected frame. */
6881 struct infcall_control_state
6883 struct thread_control_state thread_control;
6884 struct inferior_control_state inferior_control;
6887 enum stop_stack_kind stop_stack_dummy;
6888 int stopped_by_random_signal;
6889 int stop_after_trap;
6891 /* ID if the selected frame when the inferior function call was made. */
6892 struct frame_id selected_frame_id;
6895 /* Save all of the information associated with the inferior<==>gdb
6898 struct infcall_control_state *
6899 save_infcall_control_state (void)
6901 struct infcall_control_state *inf_status = xmalloc (sizeof (*inf_status));
6902 struct thread_info *tp = inferior_thread ();
6903 struct inferior *inf = current_inferior ();
6905 inf_status->thread_control = tp->control;
6906 inf_status->inferior_control = inf->control;
6908 tp->control.step_resume_breakpoint = NULL;
6909 tp->control.exception_resume_breakpoint = NULL;
6911 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
6912 chain. If caller's caller is walking the chain, they'll be happier if we
6913 hand them back the original chain when restore_infcall_control_state is
6915 tp->control.stop_bpstat = bpstat_copy (tp->control.stop_bpstat);
6918 inf_status->stop_stack_dummy = stop_stack_dummy;
6919 inf_status->stopped_by_random_signal = stopped_by_random_signal;
6920 inf_status->stop_after_trap = stop_after_trap;
6922 inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL));
6928 restore_selected_frame (void *args)
6930 struct frame_id *fid = (struct frame_id *) args;
6931 struct frame_info *frame;
6933 frame = frame_find_by_id (*fid);
6935 /* If inf_status->selected_frame_id is NULL, there was no previously
6939 warning (_("Unable to restore previously selected frame."));
6943 select_frame (frame);
6948 /* Restore inferior session state to INF_STATUS. */
6951 restore_infcall_control_state (struct infcall_control_state *inf_status)
6953 struct thread_info *tp = inferior_thread ();
6954 struct inferior *inf = current_inferior ();
6956 if (tp->control.step_resume_breakpoint)
6957 tp->control.step_resume_breakpoint->disposition = disp_del_at_next_stop;
6959 if (tp->control.exception_resume_breakpoint)
6960 tp->control.exception_resume_breakpoint->disposition
6961 = disp_del_at_next_stop;
6963 /* Handle the bpstat_copy of the chain. */
6964 bpstat_clear (&tp->control.stop_bpstat);
6966 tp->control = inf_status->thread_control;
6967 inf->control = inf_status->inferior_control;
6970 stop_stack_dummy = inf_status->stop_stack_dummy;
6971 stopped_by_random_signal = inf_status->stopped_by_random_signal;
6972 stop_after_trap = inf_status->stop_after_trap;
6974 if (target_has_stack)
6976 /* The point of catch_errors is that if the stack is clobbered,
6977 walking the stack might encounter a garbage pointer and
6978 error() trying to dereference it. */
6980 (restore_selected_frame, &inf_status->selected_frame_id,
6981 "Unable to restore previously selected frame:\n",
6982 RETURN_MASK_ERROR) == 0)
6983 /* Error in restoring the selected frame. Select the innermost
6985 select_frame (get_current_frame ());
6992 do_restore_infcall_control_state_cleanup (void *sts)
6994 restore_infcall_control_state (sts);
6998 make_cleanup_restore_infcall_control_state
6999 (struct infcall_control_state *inf_status)
7001 return make_cleanup (do_restore_infcall_control_state_cleanup, inf_status);
7005 discard_infcall_control_state (struct infcall_control_state *inf_status)
7007 if (inf_status->thread_control.step_resume_breakpoint)
7008 inf_status->thread_control.step_resume_breakpoint->disposition
7009 = disp_del_at_next_stop;
7011 if (inf_status->thread_control.exception_resume_breakpoint)
7012 inf_status->thread_control.exception_resume_breakpoint->disposition
7013 = disp_del_at_next_stop;
7015 /* See save_infcall_control_state for info on stop_bpstat. */
7016 bpstat_clear (&inf_status->thread_control.stop_bpstat);
7022 ptid_match (ptid_t ptid, ptid_t filter)
7024 if (ptid_equal (filter, minus_one_ptid))
7026 if (ptid_is_pid (filter)
7027 && ptid_get_pid (ptid) == ptid_get_pid (filter))
7029 else if (ptid_equal (ptid, filter))
7035 /* restore_inferior_ptid() will be used by the cleanup machinery
7036 to restore the inferior_ptid value saved in a call to
7037 save_inferior_ptid(). */
7040 restore_inferior_ptid (void *arg)
7042 ptid_t *saved_ptid_ptr = arg;
7044 inferior_ptid = *saved_ptid_ptr;
7048 /* Save the value of inferior_ptid so that it may be restored by a
7049 later call to do_cleanups(). Returns the struct cleanup pointer
7050 needed for later doing the cleanup. */
7053 save_inferior_ptid (void)
7055 ptid_t *saved_ptid_ptr;
7057 saved_ptid_ptr = xmalloc (sizeof (ptid_t));
7058 *saved_ptid_ptr = inferior_ptid;
7059 return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
7063 /* User interface for reverse debugging:
7064 Set exec-direction / show exec-direction commands
7065 (returns error unless target implements to_set_exec_direction method). */
7067 int execution_direction = EXEC_FORWARD;
7068 static const char exec_forward[] = "forward";
7069 static const char exec_reverse[] = "reverse";
7070 static const char *exec_direction = exec_forward;
7071 static const char *const exec_direction_names[] = {
7078 set_exec_direction_func (char *args, int from_tty,
7079 struct cmd_list_element *cmd)
7081 if (target_can_execute_reverse)
7083 if (!strcmp (exec_direction, exec_forward))
7084 execution_direction = EXEC_FORWARD;
7085 else if (!strcmp (exec_direction, exec_reverse))
7086 execution_direction = EXEC_REVERSE;
7090 exec_direction = exec_forward;
7091 error (_("Target does not support this operation."));
7096 show_exec_direction_func (struct ui_file *out, int from_tty,
7097 struct cmd_list_element *cmd, const char *value)
7099 switch (execution_direction) {
7101 fprintf_filtered (out, _("Forward.\n"));
7104 fprintf_filtered (out, _("Reverse.\n"));
7107 internal_error (__FILE__, __LINE__,
7108 _("bogus execution_direction value: %d"),
7109 (int) execution_direction);
7114 show_schedule_multiple (struct ui_file *file, int from_tty,
7115 struct cmd_list_element *c, const char *value)
7117 fprintf_filtered (file, _("Resuming the execution of threads "
7118 "of all processes is %s.\n"), value);
7121 /* Implementation of `siginfo' variable. */
7123 static const struct internalvar_funcs siginfo_funcs =
7131 _initialize_infrun (void)
7135 struct cmd_list_element *c;
7137 add_info ("signals", signals_info, _("\
7138 What debugger does when program gets various signals.\n\
7139 Specify a signal as argument to print info on that signal only."));
7140 add_info_alias ("handle", "signals", 0);
7142 c = add_com ("handle", class_run, handle_command, _("\
7143 Specify how to handle signals.\n\
7144 Usage: handle SIGNAL [ACTIONS]\n\
7145 Args are signals and actions to apply to those signals.\n\
7146 If no actions are specified, the current settings for the specified signals\n\
7147 will be displayed instead.\n\
7149 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7150 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7151 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7152 The special arg \"all\" is recognized to mean all signals except those\n\
7153 used by the debugger, typically SIGTRAP and SIGINT.\n\
7155 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7156 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7157 Stop means reenter debugger if this signal happens (implies print).\n\
7158 Print means print a message if this signal happens.\n\
7159 Pass means let program see this signal; otherwise program doesn't know.\n\
7160 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7161 Pass and Stop may be combined.\n\
7163 Multiple signals may be specified. Signal numbers and signal names\n\
7164 may be interspersed with actions, with the actions being performed for\n\
7165 all signals cumulatively specified."));
7166 set_cmd_completer (c, handle_completer);
7170 add_com ("lz", class_info, signals_info, _("\
7171 What debugger does when program gets various signals.\n\
7172 Specify a signal as argument to print info on that signal only."));
7173 add_com ("z", class_run, xdb_handle_command, _("\
7174 Specify how to handle a signal.\n\
7175 Args are signals and actions to apply to those signals.\n\
7176 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7177 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7178 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7179 The special arg \"all\" is recognized to mean all signals except those\n\
7180 used by the debugger, typically SIGTRAP and SIGINT.\n\
7181 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7182 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7183 nopass), \"Q\" (noprint)\n\
7184 Stop means reenter debugger if this signal happens (implies print).\n\
7185 Print means print a message if this signal happens.\n\
7186 Pass means let program see this signal; otherwise program doesn't know.\n\
7187 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7188 Pass and Stop may be combined."));
7192 stop_command = add_cmd ("stop", class_obscure,
7193 not_just_help_class_command, _("\
7194 There is no `stop' command, but you can set a hook on `stop'.\n\
7195 This allows you to set a list of commands to be run each time execution\n\
7196 of the program stops."), &cmdlist);
7198 add_setshow_zuinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\
7199 Set inferior debugging."), _("\
7200 Show inferior debugging."), _("\
7201 When non-zero, inferior specific debugging is enabled."),
7204 &setdebuglist, &showdebuglist);
7206 add_setshow_boolean_cmd ("displaced", class_maintenance,
7207 &debug_displaced, _("\
7208 Set displaced stepping debugging."), _("\
7209 Show displaced stepping debugging."), _("\
7210 When non-zero, displaced stepping specific debugging is enabled."),
7212 show_debug_displaced,
7213 &setdebuglist, &showdebuglist);
7215 add_setshow_boolean_cmd ("non-stop", no_class,
7217 Set whether gdb controls the inferior in non-stop mode."), _("\
7218 Show whether gdb controls the inferior in non-stop mode."), _("\
7219 When debugging a multi-threaded program and this setting is\n\
7220 off (the default, also called all-stop mode), when one thread stops\n\
7221 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7222 all other threads in the program while you interact with the thread of\n\
7223 interest. When you continue or step a thread, you can allow the other\n\
7224 threads to run, or have them remain stopped, but while you inspect any\n\
7225 thread's state, all threads stop.\n\
7227 In non-stop mode, when one thread stops, other threads can continue\n\
7228 to run freely. You'll be able to step each thread independently,\n\
7229 leave it stopped or free to run as needed."),
7235 numsigs = (int) GDB_SIGNAL_LAST;
7236 signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs);
7237 signal_print = (unsigned char *)
7238 xmalloc (sizeof (signal_print[0]) * numsigs);
7239 signal_program = (unsigned char *)
7240 xmalloc (sizeof (signal_program[0]) * numsigs);
7241 signal_catch = (unsigned char *)
7242 xmalloc (sizeof (signal_catch[0]) * numsigs);
7243 signal_pass = (unsigned char *)
7244 xmalloc (sizeof (signal_program[0]) * numsigs);
7245 for (i = 0; i < numsigs; i++)
7248 signal_print[i] = 1;
7249 signal_program[i] = 1;
7250 signal_catch[i] = 0;
7253 /* Signals caused by debugger's own actions
7254 should not be given to the program afterwards. */
7255 signal_program[GDB_SIGNAL_TRAP] = 0;
7256 signal_program[GDB_SIGNAL_INT] = 0;
7258 /* Signals that are not errors should not normally enter the debugger. */
7259 signal_stop[GDB_SIGNAL_ALRM] = 0;
7260 signal_print[GDB_SIGNAL_ALRM] = 0;
7261 signal_stop[GDB_SIGNAL_VTALRM] = 0;
7262 signal_print[GDB_SIGNAL_VTALRM] = 0;
7263 signal_stop[GDB_SIGNAL_PROF] = 0;
7264 signal_print[GDB_SIGNAL_PROF] = 0;
7265 signal_stop[GDB_SIGNAL_CHLD] = 0;
7266 signal_print[GDB_SIGNAL_CHLD] = 0;
7267 signal_stop[GDB_SIGNAL_IO] = 0;
7268 signal_print[GDB_SIGNAL_IO] = 0;
7269 signal_stop[GDB_SIGNAL_POLL] = 0;
7270 signal_print[GDB_SIGNAL_POLL] = 0;
7271 signal_stop[GDB_SIGNAL_URG] = 0;
7272 signal_print[GDB_SIGNAL_URG] = 0;
7273 signal_stop[GDB_SIGNAL_WINCH] = 0;
7274 signal_print[GDB_SIGNAL_WINCH] = 0;
7275 signal_stop[GDB_SIGNAL_PRIO] = 0;
7276 signal_print[GDB_SIGNAL_PRIO] = 0;
7278 /* These signals are used internally by user-level thread
7279 implementations. (See signal(5) on Solaris.) Like the above
7280 signals, a healthy program receives and handles them as part of
7281 its normal operation. */
7282 signal_stop[GDB_SIGNAL_LWP] = 0;
7283 signal_print[GDB_SIGNAL_LWP] = 0;
7284 signal_stop[GDB_SIGNAL_WAITING] = 0;
7285 signal_print[GDB_SIGNAL_WAITING] = 0;
7286 signal_stop[GDB_SIGNAL_CANCEL] = 0;
7287 signal_print[GDB_SIGNAL_CANCEL] = 0;
7289 /* Update cached state. */
7290 signal_cache_update (-1);
7292 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support,
7293 &stop_on_solib_events, _("\
7294 Set stopping for shared library events."), _("\
7295 Show stopping for shared library events."), _("\
7296 If nonzero, gdb will give control to the user when the dynamic linker\n\
7297 notifies gdb of shared library events. The most common event of interest\n\
7298 to the user would be loading/unloading of a new library."),
7299 set_stop_on_solib_events,
7300 show_stop_on_solib_events,
7301 &setlist, &showlist);
7303 add_setshow_enum_cmd ("follow-fork-mode", class_run,
7304 follow_fork_mode_kind_names,
7305 &follow_fork_mode_string, _("\
7306 Set debugger response to a program call of fork or vfork."), _("\
7307 Show debugger response to a program call of fork or vfork."), _("\
7308 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7309 parent - the original process is debugged after a fork\n\
7310 child - the new process is debugged after a fork\n\
7311 The unfollowed process will continue to run.\n\
7312 By default, the debugger will follow the parent process."),
7314 show_follow_fork_mode_string,
7315 &setlist, &showlist);
7317 add_setshow_enum_cmd ("follow-exec-mode", class_run,
7318 follow_exec_mode_names,
7319 &follow_exec_mode_string, _("\
7320 Set debugger response to a program call of exec."), _("\
7321 Show debugger response to a program call of exec."), _("\
7322 An exec call replaces the program image of a process.\n\
7324 follow-exec-mode can be:\n\
7326 new - the debugger creates a new inferior and rebinds the process\n\
7327 to this new inferior. The program the process was running before\n\
7328 the exec call can be restarted afterwards by restarting the original\n\
7331 same - the debugger keeps the process bound to the same inferior.\n\
7332 The new executable image replaces the previous executable loaded in\n\
7333 the inferior. Restarting the inferior after the exec call restarts\n\
7334 the executable the process was running after the exec call.\n\
7336 By default, the debugger will use the same inferior."),
7338 show_follow_exec_mode_string,
7339 &setlist, &showlist);
7341 add_setshow_enum_cmd ("scheduler-locking", class_run,
7342 scheduler_enums, &scheduler_mode, _("\
7343 Set mode for locking scheduler during execution."), _("\
7344 Show mode for locking scheduler during execution."), _("\
7345 off == no locking (threads may preempt at any time)\n\
7346 on == full locking (no thread except the current thread may run)\n\
7347 step == scheduler locked during every single-step operation.\n\
7348 In this mode, no other thread may run during a step command.\n\
7349 Other threads may run while stepping over a function call ('next')."),
7350 set_schedlock_func, /* traps on target vector */
7351 show_scheduler_mode,
7352 &setlist, &showlist);
7354 add_setshow_boolean_cmd ("schedule-multiple", class_run, &sched_multi, _("\
7355 Set mode for resuming threads of all processes."), _("\
7356 Show mode for resuming threads of all processes."), _("\
7357 When on, execution commands (such as 'continue' or 'next') resume all\n\
7358 threads of all processes. When off (which is the default), execution\n\
7359 commands only resume the threads of the current process. The set of\n\
7360 threads that are resumed is further refined by the scheduler-locking\n\
7361 mode (see help set scheduler-locking)."),
7363 show_schedule_multiple,
7364 &setlist, &showlist);
7366 add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\
7367 Set mode of the step operation."), _("\
7368 Show mode of the step operation."), _("\
7369 When set, doing a step over a function without debug line information\n\
7370 will stop at the first instruction of that function. Otherwise, the\n\
7371 function is skipped and the step command stops at a different source line."),
7373 show_step_stop_if_no_debug,
7374 &setlist, &showlist);
7376 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run,
7377 &can_use_displaced_stepping, _("\
7378 Set debugger's willingness to use displaced stepping."), _("\
7379 Show debugger's willingness to use displaced stepping."), _("\
7380 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7381 supported by the target architecture. If off, gdb will not use displaced\n\
7382 stepping to step over breakpoints, even if such is supported by the target\n\
7383 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7384 if the target architecture supports it and non-stop mode is active, but will not\n\
7385 use it in all-stop mode (see help set non-stop)."),
7387 show_can_use_displaced_stepping,
7388 &setlist, &showlist);
7390 add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names,
7391 &exec_direction, _("Set direction of execution.\n\
7392 Options are 'forward' or 'reverse'."),
7393 _("Show direction of execution (forward/reverse)."),
7394 _("Tells gdb whether to execute forward or backward."),
7395 set_exec_direction_func, show_exec_direction_func,
7396 &setlist, &showlist);
7398 /* Set/show detach-on-fork: user-settable mode. */
7400 add_setshow_boolean_cmd ("detach-on-fork", class_run, &detach_fork, _("\
7401 Set whether gdb will detach the child of a fork."), _("\
7402 Show whether gdb will detach the child of a fork."), _("\
7403 Tells gdb whether to detach the child of a fork."),
7404 NULL, NULL, &setlist, &showlist);
7406 /* Set/show disable address space randomization mode. */
7408 add_setshow_boolean_cmd ("disable-randomization", class_support,
7409 &disable_randomization, _("\
7410 Set disabling of debuggee's virtual address space randomization."), _("\
7411 Show disabling of debuggee's virtual address space randomization."), _("\
7412 When this mode is on (which is the default), randomization of the virtual\n\
7413 address space is disabled. Standalone programs run with the randomization\n\
7414 enabled by default on some platforms."),
7415 &set_disable_randomization,
7416 &show_disable_randomization,
7417 &setlist, &showlist);
7419 /* ptid initializations */
7420 inferior_ptid = null_ptid;
7421 target_last_wait_ptid = minus_one_ptid;
7423 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed);
7424 observer_attach_thread_stop_requested (infrun_thread_stop_requested);
7425 observer_attach_thread_exit (infrun_thread_thread_exit);
7426 observer_attach_inferior_exit (infrun_inferior_exit);
7428 /* Explicitly create without lookup, since that tries to create a
7429 value with a void typed value, and when we get here, gdbarch
7430 isn't initialized yet. At this point, we're quite sure there
7431 isn't another convenience variable of the same name. */
7432 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs, NULL);
7434 add_setshow_boolean_cmd ("observer", no_class,
7435 &observer_mode_1, _("\
7436 Set whether gdb controls the inferior in observer mode."), _("\
7437 Show whether gdb controls the inferior in observer mode."), _("\
7438 In observer mode, GDB can get data from the inferior, but not\n\
7439 affect its execution. Registers and memory may not be changed,\n\
7440 breakpoints may not be set, and the program cannot be interrupted\n\