1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
5 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
6 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
8 This file is part of GDB.
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program. If not, see <http://www.gnu.org/licenses/>. */
24 #include "gdb_string.h"
29 #include "exceptions.h"
30 #include "breakpoint.h"
34 #include "cli/cli-script.h"
36 #include "gdbthread.h"
48 #include "dictionary.h"
50 #include "gdb_assert.h"
51 #include "mi/mi-common.h"
52 #include "event-top.h"
54 #include "inline-frame.h"
56 #include "tracepoint.h"
57 #include "continuations.h"
61 /* Prototypes for local functions */
63 static void signals_info (char *, int);
65 static void handle_command (char *, int);
67 static void sig_print_info (enum target_signal);
69 static void sig_print_header (void);
71 static void resume_cleanups (void *);
73 static int hook_stop_stub (void *);
75 static int restore_selected_frame (void *);
77 static int follow_fork (void);
79 static void set_schedlock_func (char *args, int from_tty,
80 struct cmd_list_element *c);
82 static int currently_stepping (struct thread_info *tp);
84 static int currently_stepping_or_nexting_callback (struct thread_info *tp,
87 static void xdb_handle_command (char *args, int from_tty);
89 static int prepare_to_proceed (int);
91 static void print_exited_reason (int exitstatus);
93 static void print_signal_exited_reason (enum target_signal siggnal);
95 static void print_no_history_reason (void);
97 static void print_signal_received_reason (enum target_signal siggnal);
99 static void print_end_stepping_range_reason (void);
101 void _initialize_infrun (void);
103 void nullify_last_target_wait_ptid (void);
105 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info *);
107 static void insert_step_resume_breakpoint_at_caller (struct frame_info *);
109 static void insert_longjmp_resume_breakpoint (struct gdbarch *, CORE_ADDR);
111 /* When set, stop the 'step' command if we enter a function which has
112 no line number information. The normal behavior is that we step
113 over such function. */
114 int step_stop_if_no_debug = 0;
116 show_step_stop_if_no_debug (struct ui_file *file, int from_tty,
117 struct cmd_list_element *c, const char *value)
119 fprintf_filtered (file, _("Mode of the step operation is %s.\n"), value);
122 /* In asynchronous mode, but simulating synchronous execution. */
124 int sync_execution = 0;
126 /* wait_for_inferior and normal_stop use this to notify the user
127 when the inferior stopped in a different thread than it had been
130 static ptid_t previous_inferior_ptid;
132 /* Default behavior is to detach newly forked processes (legacy). */
135 int debug_displaced = 0;
137 show_debug_displaced (struct ui_file *file, int from_tty,
138 struct cmd_list_element *c, const char *value)
140 fprintf_filtered (file, _("Displace stepping debugging is %s.\n"), value);
143 int debug_infrun = 0;
145 show_debug_infrun (struct ui_file *file, int from_tty,
146 struct cmd_list_element *c, const char *value)
148 fprintf_filtered (file, _("Inferior debugging is %s.\n"), value);
152 /* Support for disabling address space randomization. */
154 int disable_randomization = 1;
157 show_disable_randomization (struct ui_file *file, int from_tty,
158 struct cmd_list_element *c, const char *value)
160 if (target_supports_disable_randomization ())
161 fprintf_filtered (file,
162 _("Disabling randomization of debuggee's "
163 "virtual address space is %s.\n"),
166 fputs_filtered (_("Disabling randomization of debuggee's "
167 "virtual address space is unsupported on\n"
168 "this platform.\n"), file);
172 set_disable_randomization (char *args, int from_tty,
173 struct cmd_list_element *c)
175 if (!target_supports_disable_randomization ())
176 error (_("Disabling randomization of debuggee's "
177 "virtual address space is unsupported on\n"
182 /* If the program uses ELF-style shared libraries, then calls to
183 functions in shared libraries go through stubs, which live in a
184 table called the PLT (Procedure Linkage Table). The first time the
185 function is called, the stub sends control to the dynamic linker,
186 which looks up the function's real address, patches the stub so
187 that future calls will go directly to the function, and then passes
188 control to the function.
190 If we are stepping at the source level, we don't want to see any of
191 this --- we just want to skip over the stub and the dynamic linker.
192 The simple approach is to single-step until control leaves the
195 However, on some systems (e.g., Red Hat's 5.2 distribution) the
196 dynamic linker calls functions in the shared C library, so you
197 can't tell from the PC alone whether the dynamic linker is still
198 running. In this case, we use a step-resume breakpoint to get us
199 past the dynamic linker, as if we were using "next" to step over a
202 in_solib_dynsym_resolve_code() says whether we're in the dynamic
203 linker code or not. Normally, this means we single-step. However,
204 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
205 address where we can place a step-resume breakpoint to get past the
206 linker's symbol resolution function.
208 in_solib_dynsym_resolve_code() can generally be implemented in a
209 pretty portable way, by comparing the PC against the address ranges
210 of the dynamic linker's sections.
212 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
213 it depends on internal details of the dynamic linker. It's usually
214 not too hard to figure out where to put a breakpoint, but it
215 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
216 sanity checking. If it can't figure things out, returning zero and
217 getting the (possibly confusing) stepping behavior is better than
218 signalling an error, which will obscure the change in the
221 /* This function returns TRUE if pc is the address of an instruction
222 that lies within the dynamic linker (such as the event hook, or the
225 This function must be used only when a dynamic linker event has
226 been caught, and the inferior is being stepped out of the hook, or
227 undefined results are guaranteed. */
229 #ifndef SOLIB_IN_DYNAMIC_LINKER
230 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
233 /* "Observer mode" is somewhat like a more extreme version of
234 non-stop, in which all GDB operations that might affect the
235 target's execution have been disabled. */
237 static int non_stop_1 = 0;
239 int observer_mode = 0;
240 static int observer_mode_1 = 0;
243 set_observer_mode (char *args, int from_tty,
244 struct cmd_list_element *c)
246 extern int pagination_enabled;
248 if (target_has_execution)
250 observer_mode_1 = observer_mode;
251 error (_("Cannot change this setting while the inferior is running."));
254 observer_mode = observer_mode_1;
256 may_write_registers = !observer_mode;
257 may_write_memory = !observer_mode;
258 may_insert_breakpoints = !observer_mode;
259 may_insert_tracepoints = !observer_mode;
260 /* We can insert fast tracepoints in or out of observer mode,
261 but enable them if we're going into this mode. */
263 may_insert_fast_tracepoints = 1;
264 may_stop = !observer_mode;
265 update_target_permissions ();
267 /* Going *into* observer mode we must force non-stop, then
268 going out we leave it that way. */
271 target_async_permitted = 1;
272 pagination_enabled = 0;
273 non_stop = non_stop_1 = 1;
277 printf_filtered (_("Observer mode is now %s.\n"),
278 (observer_mode ? "on" : "off"));
282 show_observer_mode (struct ui_file *file, int from_tty,
283 struct cmd_list_element *c, const char *value)
285 fprintf_filtered (file, _("Observer mode is %s.\n"), value);
288 /* This updates the value of observer mode based on changes in
289 permissions. Note that we are deliberately ignoring the values of
290 may-write-registers and may-write-memory, since the user may have
291 reason to enable these during a session, for instance to turn on a
292 debugging-related global. */
295 update_observer_mode (void)
299 newval = (!may_insert_breakpoints
300 && !may_insert_tracepoints
301 && may_insert_fast_tracepoints
305 /* Let the user know if things change. */
306 if (newval != observer_mode)
307 printf_filtered (_("Observer mode is now %s.\n"),
308 (newval ? "on" : "off"));
310 observer_mode = observer_mode_1 = newval;
313 /* Tables of how to react to signals; the user sets them. */
315 static unsigned char *signal_stop;
316 static unsigned char *signal_print;
317 static unsigned char *signal_program;
319 /* Table of signals that the target may silently handle.
320 This is automatically determined from the flags above,
321 and simply cached here. */
322 static unsigned char *signal_pass;
324 #define SET_SIGS(nsigs,sigs,flags) \
326 int signum = (nsigs); \
327 while (signum-- > 0) \
328 if ((sigs)[signum]) \
329 (flags)[signum] = 1; \
332 #define UNSET_SIGS(nsigs,sigs,flags) \
334 int signum = (nsigs); \
335 while (signum-- > 0) \
336 if ((sigs)[signum]) \
337 (flags)[signum] = 0; \
340 /* Value to pass to target_resume() to cause all threads to resume. */
342 #define RESUME_ALL minus_one_ptid
344 /* Command list pointer for the "stop" placeholder. */
346 static struct cmd_list_element *stop_command;
348 /* Function inferior was in as of last step command. */
350 static struct symbol *step_start_function;
352 /* Nonzero if we want to give control to the user when we're notified
353 of shared library events by the dynamic linker. */
354 int stop_on_solib_events;
356 show_stop_on_solib_events (struct ui_file *file, int from_tty,
357 struct cmd_list_element *c, const char *value)
359 fprintf_filtered (file, _("Stopping for shared library events is %s.\n"),
363 /* Nonzero means expecting a trace trap
364 and should stop the inferior and return silently when it happens. */
368 /* Save register contents here when executing a "finish" command or are
369 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
370 Thus this contains the return value from the called function (assuming
371 values are returned in a register). */
373 struct regcache *stop_registers;
375 /* Nonzero after stop if current stack frame should be printed. */
377 static int stop_print_frame;
379 /* This is a cached copy of the pid/waitstatus of the last event
380 returned by target_wait()/deprecated_target_wait_hook(). This
381 information is returned by get_last_target_status(). */
382 static ptid_t target_last_wait_ptid;
383 static struct target_waitstatus target_last_waitstatus;
385 static void context_switch (ptid_t ptid);
387 void init_thread_stepping_state (struct thread_info *tss);
389 void init_infwait_state (void);
391 static const char follow_fork_mode_child[] = "child";
392 static const char follow_fork_mode_parent[] = "parent";
394 static const char *follow_fork_mode_kind_names[] = {
395 follow_fork_mode_child,
396 follow_fork_mode_parent,
400 static const char *follow_fork_mode_string = follow_fork_mode_parent;
402 show_follow_fork_mode_string (struct ui_file *file, int from_tty,
403 struct cmd_list_element *c, const char *value)
405 fprintf_filtered (file,
406 _("Debugger response to a program "
407 "call of fork or vfork is \"%s\".\n"),
412 /* Tell the target to follow the fork we're stopped at. Returns true
413 if the inferior should be resumed; false, if the target for some
414 reason decided it's best not to resume. */
419 int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
420 int should_resume = 1;
421 struct thread_info *tp;
423 /* Copy user stepping state to the new inferior thread. FIXME: the
424 followed fork child thread should have a copy of most of the
425 parent thread structure's run control related fields, not just these.
426 Initialized to avoid "may be used uninitialized" warnings from gcc. */
427 struct breakpoint *step_resume_breakpoint = NULL;
428 struct breakpoint *exception_resume_breakpoint = NULL;
429 CORE_ADDR step_range_start = 0;
430 CORE_ADDR step_range_end = 0;
431 struct frame_id step_frame_id = { 0 };
436 struct target_waitstatus wait_status;
438 /* Get the last target status returned by target_wait(). */
439 get_last_target_status (&wait_ptid, &wait_status);
441 /* If not stopped at a fork event, then there's nothing else to
443 if (wait_status.kind != TARGET_WAITKIND_FORKED
444 && wait_status.kind != TARGET_WAITKIND_VFORKED)
447 /* Check if we switched over from WAIT_PTID, since the event was
449 if (!ptid_equal (wait_ptid, minus_one_ptid)
450 && !ptid_equal (inferior_ptid, wait_ptid))
452 /* We did. Switch back to WAIT_PTID thread, to tell the
453 target to follow it (in either direction). We'll
454 afterwards refuse to resume, and inform the user what
456 switch_to_thread (wait_ptid);
461 tp = inferior_thread ();
463 /* If there were any forks/vforks that were caught and are now to be
464 followed, then do so now. */
465 switch (tp->pending_follow.kind)
467 case TARGET_WAITKIND_FORKED:
468 case TARGET_WAITKIND_VFORKED:
470 ptid_t parent, child;
472 /* If the user did a next/step, etc, over a fork call,
473 preserve the stepping state in the fork child. */
474 if (follow_child && should_resume)
476 step_resume_breakpoint = clone_momentary_breakpoint
477 (tp->control.step_resume_breakpoint);
478 step_range_start = tp->control.step_range_start;
479 step_range_end = tp->control.step_range_end;
480 step_frame_id = tp->control.step_frame_id;
481 exception_resume_breakpoint
482 = clone_momentary_breakpoint (tp->control.exception_resume_breakpoint);
484 /* For now, delete the parent's sr breakpoint, otherwise,
485 parent/child sr breakpoints are considered duplicates,
486 and the child version will not be installed. Remove
487 this when the breakpoints module becomes aware of
488 inferiors and address spaces. */
489 delete_step_resume_breakpoint (tp);
490 tp->control.step_range_start = 0;
491 tp->control.step_range_end = 0;
492 tp->control.step_frame_id = null_frame_id;
493 delete_exception_resume_breakpoint (tp);
496 parent = inferior_ptid;
497 child = tp->pending_follow.value.related_pid;
499 /* Tell the target to do whatever is necessary to follow
500 either parent or child. */
501 if (target_follow_fork (follow_child))
503 /* Target refused to follow, or there's some other reason
504 we shouldn't resume. */
509 /* This pending follow fork event is now handled, one way
510 or another. The previous selected thread may be gone
511 from the lists by now, but if it is still around, need
512 to clear the pending follow request. */
513 tp = find_thread_ptid (parent);
515 tp->pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
517 /* This makes sure we don't try to apply the "Switched
518 over from WAIT_PID" logic above. */
519 nullify_last_target_wait_ptid ();
521 /* If we followed the child, switch to it... */
524 switch_to_thread (child);
526 /* ... and preserve the stepping state, in case the
527 user was stepping over the fork call. */
530 tp = inferior_thread ();
531 tp->control.step_resume_breakpoint
532 = step_resume_breakpoint;
533 tp->control.step_range_start = step_range_start;
534 tp->control.step_range_end = step_range_end;
535 tp->control.step_frame_id = step_frame_id;
536 tp->control.exception_resume_breakpoint
537 = exception_resume_breakpoint;
541 /* If we get here, it was because we're trying to
542 resume from a fork catchpoint, but, the user
543 has switched threads away from the thread that
544 forked. In that case, the resume command
545 issued is most likely not applicable to the
546 child, so just warn, and refuse to resume. */
547 warning (_("Not resuming: switched threads "
548 "before following fork child.\n"));
551 /* Reset breakpoints in the child as appropriate. */
552 follow_inferior_reset_breakpoints ();
555 switch_to_thread (parent);
559 case TARGET_WAITKIND_SPURIOUS:
560 /* Nothing to follow. */
563 internal_error (__FILE__, __LINE__,
564 "Unexpected pending_follow.kind %d\n",
565 tp->pending_follow.kind);
569 return should_resume;
573 follow_inferior_reset_breakpoints (void)
575 struct thread_info *tp = inferior_thread ();
577 /* Was there a step_resume breakpoint? (There was if the user
578 did a "next" at the fork() call.) If so, explicitly reset its
581 step_resumes are a form of bp that are made to be per-thread.
582 Since we created the step_resume bp when the parent process
583 was being debugged, and now are switching to the child process,
584 from the breakpoint package's viewpoint, that's a switch of
585 "threads". We must update the bp's notion of which thread
586 it is for, or it'll be ignored when it triggers. */
588 if (tp->control.step_resume_breakpoint)
589 breakpoint_re_set_thread (tp->control.step_resume_breakpoint);
591 if (tp->control.exception_resume_breakpoint)
592 breakpoint_re_set_thread (tp->control.exception_resume_breakpoint);
594 /* Reinsert all breakpoints in the child. The user may have set
595 breakpoints after catching the fork, in which case those
596 were never set in the child, but only in the parent. This makes
597 sure the inserted breakpoints match the breakpoint list. */
599 breakpoint_re_set ();
600 insert_breakpoints ();
603 /* The child has exited or execed: resume threads of the parent the
604 user wanted to be executing. */
607 proceed_after_vfork_done (struct thread_info *thread,
610 int pid = * (int *) arg;
612 if (ptid_get_pid (thread->ptid) == pid
613 && is_running (thread->ptid)
614 && !is_executing (thread->ptid)
615 && !thread->stop_requested
616 && thread->suspend.stop_signal == TARGET_SIGNAL_0)
619 fprintf_unfiltered (gdb_stdlog,
620 "infrun: resuming vfork parent thread %s\n",
621 target_pid_to_str (thread->ptid));
623 switch_to_thread (thread->ptid);
624 clear_proceed_status ();
625 proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 0);
631 /* Called whenever we notice an exec or exit event, to handle
632 detaching or resuming a vfork parent. */
635 handle_vfork_child_exec_or_exit (int exec)
637 struct inferior *inf = current_inferior ();
639 if (inf->vfork_parent)
641 int resume_parent = -1;
643 /* This exec or exit marks the end of the shared memory region
644 between the parent and the child. If the user wanted to
645 detach from the parent, now is the time. */
647 if (inf->vfork_parent->pending_detach)
649 struct thread_info *tp;
650 struct cleanup *old_chain;
651 struct program_space *pspace;
652 struct address_space *aspace;
654 /* follow-fork child, detach-on-fork on. */
656 old_chain = make_cleanup_restore_current_thread ();
658 /* We're letting loose of the parent. */
659 tp = any_live_thread_of_process (inf->vfork_parent->pid);
660 switch_to_thread (tp->ptid);
662 /* We're about to detach from the parent, which implicitly
663 removes breakpoints from its address space. There's a
664 catch here: we want to reuse the spaces for the child,
665 but, parent/child are still sharing the pspace at this
666 point, although the exec in reality makes the kernel give
667 the child a fresh set of new pages. The problem here is
668 that the breakpoints module being unaware of this, would
669 likely chose the child process to write to the parent
670 address space. Swapping the child temporarily away from
671 the spaces has the desired effect. Yes, this is "sort
674 pspace = inf->pspace;
675 aspace = inf->aspace;
679 if (debug_infrun || info_verbose)
681 target_terminal_ours ();
684 fprintf_filtered (gdb_stdlog,
685 "Detaching vfork parent process "
686 "%d after child exec.\n",
687 inf->vfork_parent->pid);
689 fprintf_filtered (gdb_stdlog,
690 "Detaching vfork parent process "
691 "%d after child exit.\n",
692 inf->vfork_parent->pid);
695 target_detach (NULL, 0);
698 inf->pspace = pspace;
699 inf->aspace = aspace;
701 do_cleanups (old_chain);
705 /* We're staying attached to the parent, so, really give the
706 child a new address space. */
707 inf->pspace = add_program_space (maybe_new_address_space ());
708 inf->aspace = inf->pspace->aspace;
710 set_current_program_space (inf->pspace);
712 resume_parent = inf->vfork_parent->pid;
714 /* Break the bonds. */
715 inf->vfork_parent->vfork_child = NULL;
719 struct cleanup *old_chain;
720 struct program_space *pspace;
722 /* If this is a vfork child exiting, then the pspace and
723 aspaces were shared with the parent. Since we're
724 reporting the process exit, we'll be mourning all that is
725 found in the address space, and switching to null_ptid,
726 preparing to start a new inferior. But, since we don't
727 want to clobber the parent's address/program spaces, we
728 go ahead and create a new one for this exiting
731 /* Switch to null_ptid, so that clone_program_space doesn't want
732 to read the selected frame of a dead process. */
733 old_chain = save_inferior_ptid ();
734 inferior_ptid = null_ptid;
736 /* This inferior is dead, so avoid giving the breakpoints
737 module the option to write through to it (cloning a
738 program space resets breakpoints). */
741 pspace = add_program_space (maybe_new_address_space ());
742 set_current_program_space (pspace);
744 clone_program_space (pspace, inf->vfork_parent->pspace);
745 inf->pspace = pspace;
746 inf->aspace = pspace->aspace;
748 /* Put back inferior_ptid. We'll continue mourning this
750 do_cleanups (old_chain);
752 resume_parent = inf->vfork_parent->pid;
753 /* Break the bonds. */
754 inf->vfork_parent->vfork_child = NULL;
757 inf->vfork_parent = NULL;
759 gdb_assert (current_program_space == inf->pspace);
761 if (non_stop && resume_parent != -1)
763 /* If the user wanted the parent to be running, let it go
765 struct cleanup *old_chain = make_cleanup_restore_current_thread ();
768 fprintf_unfiltered (gdb_stdlog,
769 "infrun: resuming vfork parent process %d\n",
772 iterate_over_threads (proceed_after_vfork_done, &resume_parent);
774 do_cleanups (old_chain);
779 /* Enum strings for "set|show displaced-stepping". */
781 static const char follow_exec_mode_new[] = "new";
782 static const char follow_exec_mode_same[] = "same";
783 static const char *follow_exec_mode_names[] =
785 follow_exec_mode_new,
786 follow_exec_mode_same,
790 static const char *follow_exec_mode_string = follow_exec_mode_same;
792 show_follow_exec_mode_string (struct ui_file *file, int from_tty,
793 struct cmd_list_element *c, const char *value)
795 fprintf_filtered (file, _("Follow exec mode is \"%s\".\n"), value);
798 /* EXECD_PATHNAME is assumed to be non-NULL. */
801 follow_exec (ptid_t pid, char *execd_pathname)
803 struct thread_info *th = inferior_thread ();
804 struct inferior *inf = current_inferior ();
806 /* This is an exec event that we actually wish to pay attention to.
807 Refresh our symbol table to the newly exec'd program, remove any
810 If there are breakpoints, they aren't really inserted now,
811 since the exec() transformed our inferior into a fresh set
814 We want to preserve symbolic breakpoints on the list, since
815 we have hopes that they can be reset after the new a.out's
816 symbol table is read.
818 However, any "raw" breakpoints must be removed from the list
819 (e.g., the solib bp's), since their address is probably invalid
822 And, we DON'T want to call delete_breakpoints() here, since
823 that may write the bp's "shadow contents" (the instruction
824 value that was overwritten witha TRAP instruction). Since
825 we now have a new a.out, those shadow contents aren't valid. */
827 mark_breakpoints_out ();
829 update_breakpoints_after_exec ();
831 /* If there was one, it's gone now. We cannot truly step-to-next
832 statement through an exec(). */
833 th->control.step_resume_breakpoint = NULL;
834 th->control.exception_resume_breakpoint = NULL;
835 th->control.step_range_start = 0;
836 th->control.step_range_end = 0;
838 /* The target reports the exec event to the main thread, even if
839 some other thread does the exec, and even if the main thread was
840 already stopped --- if debugging in non-stop mode, it's possible
841 the user had the main thread held stopped in the previous image
842 --- release it now. This is the same behavior as step-over-exec
843 with scheduler-locking on in all-stop mode. */
844 th->stop_requested = 0;
846 /* What is this a.out's name? */
847 printf_unfiltered (_("%s is executing new program: %s\n"),
848 target_pid_to_str (inferior_ptid),
851 /* We've followed the inferior through an exec. Therefore, the
852 inferior has essentially been killed & reborn. */
854 gdb_flush (gdb_stdout);
856 breakpoint_init_inferior (inf_execd);
858 if (gdb_sysroot && *gdb_sysroot)
860 char *name = alloca (strlen (gdb_sysroot)
861 + strlen (execd_pathname)
864 strcpy (name, gdb_sysroot);
865 strcat (name, execd_pathname);
866 execd_pathname = name;
869 /* Reset the shared library package. This ensures that we get a
870 shlib event when the child reaches "_start", at which point the
871 dld will have had a chance to initialize the child. */
872 /* Also, loading a symbol file below may trigger symbol lookups, and
873 we don't want those to be satisfied by the libraries of the
874 previous incarnation of this process. */
875 no_shared_libraries (NULL, 0);
877 if (follow_exec_mode_string == follow_exec_mode_new)
879 struct program_space *pspace;
881 /* The user wants to keep the old inferior and program spaces
882 around. Create a new fresh one, and switch to it. */
884 inf = add_inferior (current_inferior ()->pid);
885 pspace = add_program_space (maybe_new_address_space ());
886 inf->pspace = pspace;
887 inf->aspace = pspace->aspace;
889 exit_inferior_num_silent (current_inferior ()->num);
891 set_current_inferior (inf);
892 set_current_program_space (pspace);
895 gdb_assert (current_program_space == inf->pspace);
897 /* That a.out is now the one to use. */
898 exec_file_attach (execd_pathname, 0);
900 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
901 (Position Independent Executable) main symbol file will get applied by
902 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
903 the breakpoints with the zero displacement. */
905 symbol_file_add (execd_pathname, SYMFILE_MAINLINE | SYMFILE_DEFER_BP_RESET,
908 set_initial_language ();
910 #ifdef SOLIB_CREATE_INFERIOR_HOOK
911 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid));
913 solib_create_inferior_hook (0);
916 jit_inferior_created_hook ();
918 breakpoint_re_set ();
920 /* Reinsert all breakpoints. (Those which were symbolic have
921 been reset to the proper address in the new a.out, thanks
922 to symbol_file_command...). */
923 insert_breakpoints ();
925 /* The next resume of this inferior should bring it to the shlib
926 startup breakpoints. (If the user had also set bp's on
927 "main" from the old (parent) process, then they'll auto-
928 matically get reset there in the new process.). */
931 /* Non-zero if we just simulating a single-step. This is needed
932 because we cannot remove the breakpoints in the inferior process
933 until after the `wait' in `wait_for_inferior'. */
934 static int singlestep_breakpoints_inserted_p = 0;
936 /* The thread we inserted single-step breakpoints for. */
937 static ptid_t singlestep_ptid;
939 /* PC when we started this single-step. */
940 static CORE_ADDR singlestep_pc;
942 /* If another thread hit the singlestep breakpoint, we save the original
943 thread here so that we can resume single-stepping it later. */
944 static ptid_t saved_singlestep_ptid;
945 static int stepping_past_singlestep_breakpoint;
947 /* If not equal to null_ptid, this means that after stepping over breakpoint
948 is finished, we need to switch to deferred_step_ptid, and step it.
950 The use case is when one thread has hit a breakpoint, and then the user
951 has switched to another thread and issued 'step'. We need to step over
952 breakpoint in the thread which hit the breakpoint, but then continue
953 stepping the thread user has selected. */
954 static ptid_t deferred_step_ptid;
956 /* Displaced stepping. */
958 /* In non-stop debugging mode, we must take special care to manage
959 breakpoints properly; in particular, the traditional strategy for
960 stepping a thread past a breakpoint it has hit is unsuitable.
961 'Displaced stepping' is a tactic for stepping one thread past a
962 breakpoint it has hit while ensuring that other threads running
963 concurrently will hit the breakpoint as they should.
965 The traditional way to step a thread T off a breakpoint in a
966 multi-threaded program in all-stop mode is as follows:
968 a0) Initially, all threads are stopped, and breakpoints are not
970 a1) We single-step T, leaving breakpoints uninserted.
971 a2) We insert breakpoints, and resume all threads.
973 In non-stop debugging, however, this strategy is unsuitable: we
974 don't want to have to stop all threads in the system in order to
975 continue or step T past a breakpoint. Instead, we use displaced
978 n0) Initially, T is stopped, other threads are running, and
979 breakpoints are inserted.
980 n1) We copy the instruction "under" the breakpoint to a separate
981 location, outside the main code stream, making any adjustments
982 to the instruction, register, and memory state as directed by
984 n2) We single-step T over the instruction at its new location.
985 n3) We adjust the resulting register and memory state as directed
986 by T's architecture. This includes resetting T's PC to point
987 back into the main instruction stream.
990 This approach depends on the following gdbarch methods:
992 - gdbarch_max_insn_length and gdbarch_displaced_step_location
993 indicate where to copy the instruction, and how much space must
994 be reserved there. We use these in step n1.
996 - gdbarch_displaced_step_copy_insn copies a instruction to a new
997 address, and makes any necessary adjustments to the instruction,
998 register contents, and memory. We use this in step n1.
1000 - gdbarch_displaced_step_fixup adjusts registers and memory after
1001 we have successfuly single-stepped the instruction, to yield the
1002 same effect the instruction would have had if we had executed it
1003 at its original address. We use this in step n3.
1005 - gdbarch_displaced_step_free_closure provides cleanup.
1007 The gdbarch_displaced_step_copy_insn and
1008 gdbarch_displaced_step_fixup functions must be written so that
1009 copying an instruction with gdbarch_displaced_step_copy_insn,
1010 single-stepping across the copied instruction, and then applying
1011 gdbarch_displaced_insn_fixup should have the same effects on the
1012 thread's memory and registers as stepping the instruction in place
1013 would have. Exactly which responsibilities fall to the copy and
1014 which fall to the fixup is up to the author of those functions.
1016 See the comments in gdbarch.sh for details.
1018 Note that displaced stepping and software single-step cannot
1019 currently be used in combination, although with some care I think
1020 they could be made to. Software single-step works by placing
1021 breakpoints on all possible subsequent instructions; if the
1022 displaced instruction is a PC-relative jump, those breakpoints
1023 could fall in very strange places --- on pages that aren't
1024 executable, or at addresses that are not proper instruction
1025 boundaries. (We do generally let other threads run while we wait
1026 to hit the software single-step breakpoint, and they might
1027 encounter such a corrupted instruction.) One way to work around
1028 this would be to have gdbarch_displaced_step_copy_insn fully
1029 simulate the effect of PC-relative instructions (and return NULL)
1030 on architectures that use software single-stepping.
1032 In non-stop mode, we can have independent and simultaneous step
1033 requests, so more than one thread may need to simultaneously step
1034 over a breakpoint. The current implementation assumes there is
1035 only one scratch space per process. In this case, we have to
1036 serialize access to the scratch space. If thread A wants to step
1037 over a breakpoint, but we are currently waiting for some other
1038 thread to complete a displaced step, we leave thread A stopped and
1039 place it in the displaced_step_request_queue. Whenever a displaced
1040 step finishes, we pick the next thread in the queue and start a new
1041 displaced step operation on it. See displaced_step_prepare and
1042 displaced_step_fixup for details. */
1044 struct displaced_step_request
1047 struct displaced_step_request *next;
1050 /* Per-inferior displaced stepping state. */
1051 struct displaced_step_inferior_state
1053 /* Pointer to next in linked list. */
1054 struct displaced_step_inferior_state *next;
1056 /* The process this displaced step state refers to. */
1059 /* A queue of pending displaced stepping requests. One entry per
1060 thread that needs to do a displaced step. */
1061 struct displaced_step_request *step_request_queue;
1063 /* If this is not null_ptid, this is the thread carrying out a
1064 displaced single-step in process PID. This thread's state will
1065 require fixing up once it has completed its step. */
1068 /* The architecture the thread had when we stepped it. */
1069 struct gdbarch *step_gdbarch;
1071 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1072 for post-step cleanup. */
1073 struct displaced_step_closure *step_closure;
1075 /* The address of the original instruction, and the copy we
1077 CORE_ADDR step_original, step_copy;
1079 /* Saved contents of copy area. */
1080 gdb_byte *step_saved_copy;
1083 /* The list of states of processes involved in displaced stepping
1085 static struct displaced_step_inferior_state *displaced_step_inferior_states;
1087 /* Get the displaced stepping state of process PID. */
1089 static struct displaced_step_inferior_state *
1090 get_displaced_stepping_state (int pid)
1092 struct displaced_step_inferior_state *state;
1094 for (state = displaced_step_inferior_states;
1096 state = state->next)
1097 if (state->pid == pid)
1103 /* Add a new displaced stepping state for process PID to the displaced
1104 stepping state list, or return a pointer to an already existing
1105 entry, if it already exists. Never returns NULL. */
1107 static struct displaced_step_inferior_state *
1108 add_displaced_stepping_state (int pid)
1110 struct displaced_step_inferior_state *state;
1112 for (state = displaced_step_inferior_states;
1114 state = state->next)
1115 if (state->pid == pid)
1118 state = xcalloc (1, sizeof (*state));
1120 state->next = displaced_step_inferior_states;
1121 displaced_step_inferior_states = state;
1126 /* If inferior is in displaced stepping, and ADDR equals to starting address
1127 of copy area, return corresponding displaced_step_closure. Otherwise,
1130 struct displaced_step_closure*
1131 get_displaced_step_closure_by_addr (CORE_ADDR addr)
1133 struct displaced_step_inferior_state *displaced
1134 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
1136 /* If checking the mode of displaced instruction in copy area. */
1137 if (displaced && !ptid_equal (displaced->step_ptid, null_ptid)
1138 && (displaced->step_copy == addr))
1139 return displaced->step_closure;
1144 /* Remove the displaced stepping state of process PID. */
1147 remove_displaced_stepping_state (int pid)
1149 struct displaced_step_inferior_state *it, **prev_next_p;
1151 gdb_assert (pid != 0);
1153 it = displaced_step_inferior_states;
1154 prev_next_p = &displaced_step_inferior_states;
1159 *prev_next_p = it->next;
1164 prev_next_p = &it->next;
1170 infrun_inferior_exit (struct inferior *inf)
1172 remove_displaced_stepping_state (inf->pid);
1175 /* Enum strings for "set|show displaced-stepping". */
1177 static const char can_use_displaced_stepping_auto[] = "auto";
1178 static const char can_use_displaced_stepping_on[] = "on";
1179 static const char can_use_displaced_stepping_off[] = "off";
1180 static const char *can_use_displaced_stepping_enum[] =
1182 can_use_displaced_stepping_auto,
1183 can_use_displaced_stepping_on,
1184 can_use_displaced_stepping_off,
1188 /* If ON, and the architecture supports it, GDB will use displaced
1189 stepping to step over breakpoints. If OFF, or if the architecture
1190 doesn't support it, GDB will instead use the traditional
1191 hold-and-step approach. If AUTO (which is the default), GDB will
1192 decide which technique to use to step over breakpoints depending on
1193 which of all-stop or non-stop mode is active --- displaced stepping
1194 in non-stop mode; hold-and-step in all-stop mode. */
1196 static const char *can_use_displaced_stepping =
1197 can_use_displaced_stepping_auto;
1200 show_can_use_displaced_stepping (struct ui_file *file, int from_tty,
1201 struct cmd_list_element *c,
1204 if (can_use_displaced_stepping == can_use_displaced_stepping_auto)
1205 fprintf_filtered (file,
1206 _("Debugger's willingness to use displaced stepping "
1207 "to step over breakpoints is %s (currently %s).\n"),
1208 value, non_stop ? "on" : "off");
1210 fprintf_filtered (file,
1211 _("Debugger's willingness to use displaced stepping "
1212 "to step over breakpoints is %s.\n"), value);
1215 /* Return non-zero if displaced stepping can/should be used to step
1216 over breakpoints. */
1219 use_displaced_stepping (struct gdbarch *gdbarch)
1221 return (((can_use_displaced_stepping == can_use_displaced_stepping_auto
1223 || can_use_displaced_stepping == can_use_displaced_stepping_on)
1224 && gdbarch_displaced_step_copy_insn_p (gdbarch)
1225 && !RECORD_IS_USED);
1228 /* Clean out any stray displaced stepping state. */
1230 displaced_step_clear (struct displaced_step_inferior_state *displaced)
1232 /* Indicate that there is no cleanup pending. */
1233 displaced->step_ptid = null_ptid;
1235 if (displaced->step_closure)
1237 gdbarch_displaced_step_free_closure (displaced->step_gdbarch,
1238 displaced->step_closure);
1239 displaced->step_closure = NULL;
1244 displaced_step_clear_cleanup (void *arg)
1246 struct displaced_step_inferior_state *state = arg;
1248 displaced_step_clear (state);
1251 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1253 displaced_step_dump_bytes (struct ui_file *file,
1254 const gdb_byte *buf,
1259 for (i = 0; i < len; i++)
1260 fprintf_unfiltered (file, "%02x ", buf[i]);
1261 fputs_unfiltered ("\n", file);
1264 /* Prepare to single-step, using displaced stepping.
1266 Note that we cannot use displaced stepping when we have a signal to
1267 deliver. If we have a signal to deliver and an instruction to step
1268 over, then after the step, there will be no indication from the
1269 target whether the thread entered a signal handler or ignored the
1270 signal and stepped over the instruction successfully --- both cases
1271 result in a simple SIGTRAP. In the first case we mustn't do a
1272 fixup, and in the second case we must --- but we can't tell which.
1273 Comments in the code for 'random signals' in handle_inferior_event
1274 explain how we handle this case instead.
1276 Returns 1 if preparing was successful -- this thread is going to be
1277 stepped now; or 0 if displaced stepping this thread got queued. */
1279 displaced_step_prepare (ptid_t ptid)
1281 struct cleanup *old_cleanups, *ignore_cleanups;
1282 struct regcache *regcache = get_thread_regcache (ptid);
1283 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1284 CORE_ADDR original, copy;
1286 struct displaced_step_closure *closure;
1287 struct displaced_step_inferior_state *displaced;
1289 /* We should never reach this function if the architecture does not
1290 support displaced stepping. */
1291 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch));
1293 /* We have to displaced step one thread at a time, as we only have
1294 access to a single scratch space per inferior. */
1296 displaced = add_displaced_stepping_state (ptid_get_pid (ptid));
1298 if (!ptid_equal (displaced->step_ptid, null_ptid))
1300 /* Already waiting for a displaced step to finish. Defer this
1301 request and place in queue. */
1302 struct displaced_step_request *req, *new_req;
1304 if (debug_displaced)
1305 fprintf_unfiltered (gdb_stdlog,
1306 "displaced: defering step of %s\n",
1307 target_pid_to_str (ptid));
1309 new_req = xmalloc (sizeof (*new_req));
1310 new_req->ptid = ptid;
1311 new_req->next = NULL;
1313 if (displaced->step_request_queue)
1315 for (req = displaced->step_request_queue;
1319 req->next = new_req;
1322 displaced->step_request_queue = new_req;
1328 if (debug_displaced)
1329 fprintf_unfiltered (gdb_stdlog,
1330 "displaced: stepping %s now\n",
1331 target_pid_to_str (ptid));
1334 displaced_step_clear (displaced);
1336 old_cleanups = save_inferior_ptid ();
1337 inferior_ptid = ptid;
1339 original = regcache_read_pc (regcache);
1341 copy = gdbarch_displaced_step_location (gdbarch);
1342 len = gdbarch_max_insn_length (gdbarch);
1344 /* Save the original contents of the copy area. */
1345 displaced->step_saved_copy = xmalloc (len);
1346 ignore_cleanups = make_cleanup (free_current_contents,
1347 &displaced->step_saved_copy);
1348 read_memory (copy, displaced->step_saved_copy, len);
1349 if (debug_displaced)
1351 fprintf_unfiltered (gdb_stdlog, "displaced: saved %s: ",
1352 paddress (gdbarch, copy));
1353 displaced_step_dump_bytes (gdb_stdlog,
1354 displaced->step_saved_copy,
1358 closure = gdbarch_displaced_step_copy_insn (gdbarch,
1359 original, copy, regcache);
1361 /* We don't support the fully-simulated case at present. */
1362 gdb_assert (closure);
1364 /* Save the information we need to fix things up if the step
1366 displaced->step_ptid = ptid;
1367 displaced->step_gdbarch = gdbarch;
1368 displaced->step_closure = closure;
1369 displaced->step_original = original;
1370 displaced->step_copy = copy;
1372 make_cleanup (displaced_step_clear_cleanup, displaced);
1374 /* Resume execution at the copy. */
1375 regcache_write_pc (regcache, copy);
1377 discard_cleanups (ignore_cleanups);
1379 do_cleanups (old_cleanups);
1381 if (debug_displaced)
1382 fprintf_unfiltered (gdb_stdlog, "displaced: displaced pc to %s\n",
1383 paddress (gdbarch, copy));
1389 write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr,
1390 const gdb_byte *myaddr, int len)
1392 struct cleanup *ptid_cleanup = save_inferior_ptid ();
1394 inferior_ptid = ptid;
1395 write_memory (memaddr, myaddr, len);
1396 do_cleanups (ptid_cleanup);
1399 /* Restore the contents of the copy area for thread PTID. */
1402 displaced_step_restore (struct displaced_step_inferior_state *displaced,
1405 ULONGEST len = gdbarch_max_insn_length (displaced->step_gdbarch);
1407 write_memory_ptid (ptid, displaced->step_copy,
1408 displaced->step_saved_copy, len);
1409 if (debug_displaced)
1410 fprintf_unfiltered (gdb_stdlog, "displaced: restored %s %s\n",
1411 target_pid_to_str (ptid),
1412 paddress (displaced->step_gdbarch,
1413 displaced->step_copy));
1417 displaced_step_fixup (ptid_t event_ptid, enum target_signal signal)
1419 struct cleanup *old_cleanups;
1420 struct displaced_step_inferior_state *displaced
1421 = get_displaced_stepping_state (ptid_get_pid (event_ptid));
1423 /* Was any thread of this process doing a displaced step? */
1424 if (displaced == NULL)
1427 /* Was this event for the pid we displaced? */
1428 if (ptid_equal (displaced->step_ptid, null_ptid)
1429 || ! ptid_equal (displaced->step_ptid, event_ptid))
1432 old_cleanups = make_cleanup (displaced_step_clear_cleanup, displaced);
1434 displaced_step_restore (displaced, displaced->step_ptid);
1436 /* Did the instruction complete successfully? */
1437 if (signal == TARGET_SIGNAL_TRAP)
1439 /* Fix up the resulting state. */
1440 gdbarch_displaced_step_fixup (displaced->step_gdbarch,
1441 displaced->step_closure,
1442 displaced->step_original,
1443 displaced->step_copy,
1444 get_thread_regcache (displaced->step_ptid));
1448 /* Since the instruction didn't complete, all we can do is
1450 struct regcache *regcache = get_thread_regcache (event_ptid);
1451 CORE_ADDR pc = regcache_read_pc (regcache);
1453 pc = displaced->step_original + (pc - displaced->step_copy);
1454 regcache_write_pc (regcache, pc);
1457 do_cleanups (old_cleanups);
1459 displaced->step_ptid = null_ptid;
1461 /* Are there any pending displaced stepping requests? If so, run
1462 one now. Leave the state object around, since we're likely to
1463 need it again soon. */
1464 while (displaced->step_request_queue)
1466 struct displaced_step_request *head;
1468 struct regcache *regcache;
1469 struct gdbarch *gdbarch;
1470 CORE_ADDR actual_pc;
1471 struct address_space *aspace;
1473 head = displaced->step_request_queue;
1475 displaced->step_request_queue = head->next;
1478 context_switch (ptid);
1480 regcache = get_thread_regcache (ptid);
1481 actual_pc = regcache_read_pc (regcache);
1482 aspace = get_regcache_aspace (regcache);
1484 if (breakpoint_here_p (aspace, actual_pc))
1486 if (debug_displaced)
1487 fprintf_unfiltered (gdb_stdlog,
1488 "displaced: stepping queued %s now\n",
1489 target_pid_to_str (ptid));
1491 displaced_step_prepare (ptid);
1493 gdbarch = get_regcache_arch (regcache);
1495 if (debug_displaced)
1497 CORE_ADDR actual_pc = regcache_read_pc (regcache);
1500 fprintf_unfiltered (gdb_stdlog, "displaced: run %s: ",
1501 paddress (gdbarch, actual_pc));
1502 read_memory (actual_pc, buf, sizeof (buf));
1503 displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
1506 if (gdbarch_displaced_step_hw_singlestep (gdbarch,
1507 displaced->step_closure))
1508 target_resume (ptid, 1, TARGET_SIGNAL_0);
1510 target_resume (ptid, 0, TARGET_SIGNAL_0);
1512 /* Done, we're stepping a thread. */
1518 struct thread_info *tp = inferior_thread ();
1520 /* The breakpoint we were sitting under has since been
1522 tp->control.trap_expected = 0;
1524 /* Go back to what we were trying to do. */
1525 step = currently_stepping (tp);
1527 if (debug_displaced)
1528 fprintf_unfiltered (gdb_stdlog,
1529 "breakpoint is gone %s: step(%d)\n",
1530 target_pid_to_str (tp->ptid), step);
1532 target_resume (ptid, step, TARGET_SIGNAL_0);
1533 tp->suspend.stop_signal = TARGET_SIGNAL_0;
1535 /* This request was discarded. See if there's any other
1536 thread waiting for its turn. */
1541 /* Update global variables holding ptids to hold NEW_PTID if they were
1542 holding OLD_PTID. */
1544 infrun_thread_ptid_changed (ptid_t old_ptid, ptid_t new_ptid)
1546 struct displaced_step_request *it;
1547 struct displaced_step_inferior_state *displaced;
1549 if (ptid_equal (inferior_ptid, old_ptid))
1550 inferior_ptid = new_ptid;
1552 if (ptid_equal (singlestep_ptid, old_ptid))
1553 singlestep_ptid = new_ptid;
1555 if (ptid_equal (deferred_step_ptid, old_ptid))
1556 deferred_step_ptid = new_ptid;
1558 for (displaced = displaced_step_inferior_states;
1560 displaced = displaced->next)
1562 if (ptid_equal (displaced->step_ptid, old_ptid))
1563 displaced->step_ptid = new_ptid;
1565 for (it = displaced->step_request_queue; it; it = it->next)
1566 if (ptid_equal (it->ptid, old_ptid))
1567 it->ptid = new_ptid;
1574 /* Things to clean up if we QUIT out of resume (). */
1576 resume_cleanups (void *ignore)
1581 static const char schedlock_off[] = "off";
1582 static const char schedlock_on[] = "on";
1583 static const char schedlock_step[] = "step";
1584 static const char *scheduler_enums[] = {
1590 static const char *scheduler_mode = schedlock_off;
1592 show_scheduler_mode (struct ui_file *file, int from_tty,
1593 struct cmd_list_element *c, const char *value)
1595 fprintf_filtered (file,
1596 _("Mode for locking scheduler "
1597 "during execution is \"%s\".\n"),
1602 set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
1604 if (!target_can_lock_scheduler)
1606 scheduler_mode = schedlock_off;
1607 error (_("Target '%s' cannot support this command."), target_shortname);
1611 /* True if execution commands resume all threads of all processes by
1612 default; otherwise, resume only threads of the current inferior
1614 int sched_multi = 0;
1616 /* Try to setup for software single stepping over the specified location.
1617 Return 1 if target_resume() should use hardware single step.
1619 GDBARCH the current gdbarch.
1620 PC the location to step over. */
1623 maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc)
1627 if (execution_direction == EXEC_FORWARD
1628 && gdbarch_software_single_step_p (gdbarch)
1629 && gdbarch_software_single_step (gdbarch, get_current_frame ()))
1632 /* Do not pull these breakpoints until after a `wait' in
1633 `wait_for_inferior'. */
1634 singlestep_breakpoints_inserted_p = 1;
1635 singlestep_ptid = inferior_ptid;
1641 /* Return a ptid representing the set of threads that we will proceed,
1642 in the perspective of the user/frontend. We may actually resume
1643 fewer threads at first, e.g., if a thread is stopped at a
1644 breakpoint that needs stepping-off, but that should not be visible
1645 to the user/frontend, and neither should the frontend/user be
1646 allowed to proceed any of the threads that happen to be stopped for
1647 internal run control handling, if a previous command wanted them
1651 user_visible_resume_ptid (int step)
1653 /* By default, resume all threads of all processes. */
1654 ptid_t resume_ptid = RESUME_ALL;
1656 /* Maybe resume only all threads of the current process. */
1657 if (!sched_multi && target_supports_multi_process ())
1659 resume_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
1662 /* Maybe resume a single thread after all. */
1665 /* With non-stop mode on, threads are always handled
1667 resume_ptid = inferior_ptid;
1669 else if ((scheduler_mode == schedlock_on)
1670 || (scheduler_mode == schedlock_step
1671 && (step || singlestep_breakpoints_inserted_p)))
1673 /* User-settable 'scheduler' mode requires solo thread resume. */
1674 resume_ptid = inferior_ptid;
1680 /* Resume the inferior, but allow a QUIT. This is useful if the user
1681 wants to interrupt some lengthy single-stepping operation
1682 (for child processes, the SIGINT goes to the inferior, and so
1683 we get a SIGINT random_signal, but for remote debugging and perhaps
1684 other targets, that's not true).
1686 STEP nonzero if we should step (zero to continue instead).
1687 SIG is the signal to give the inferior (zero for none). */
1689 resume (int step, enum target_signal sig)
1691 int should_resume = 1;
1692 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
1693 struct regcache *regcache = get_current_regcache ();
1694 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1695 struct thread_info *tp = inferior_thread ();
1696 CORE_ADDR pc = regcache_read_pc (regcache);
1697 struct address_space *aspace = get_regcache_aspace (regcache);
1701 if (current_inferior ()->waiting_for_vfork_done)
1703 /* Don't try to single-step a vfork parent that is waiting for
1704 the child to get out of the shared memory region (by exec'ing
1705 or exiting). This is particularly important on software
1706 single-step archs, as the child process would trip on the
1707 software single step breakpoint inserted for the parent
1708 process. Since the parent will not actually execute any
1709 instruction until the child is out of the shared region (such
1710 are vfork's semantics), it is safe to simply continue it.
1711 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
1712 the parent, and tell it to `keep_going', which automatically
1713 re-sets it stepping. */
1715 fprintf_unfiltered (gdb_stdlog,
1716 "infrun: resume : clear step\n");
1721 fprintf_unfiltered (gdb_stdlog,
1722 "infrun: resume (step=%d, signal=%d), "
1723 "trap_expected=%d, current thread [%s] at %s\n",
1724 step, sig, tp->control.trap_expected,
1725 target_pid_to_str (inferior_ptid),
1726 paddress (gdbarch, pc));
1728 /* Normally, by the time we reach `resume', the breakpoints are either
1729 removed or inserted, as appropriate. The exception is if we're sitting
1730 at a permanent breakpoint; we need to step over it, but permanent
1731 breakpoints can't be removed. So we have to test for it here. */
1732 if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here)
1734 if (gdbarch_skip_permanent_breakpoint_p (gdbarch))
1735 gdbarch_skip_permanent_breakpoint (gdbarch, regcache);
1738 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1739 how to step past a permanent breakpoint on this architecture. Try using\n\
1740 a command like `return' or `jump' to continue execution."));
1743 /* If enabled, step over breakpoints by executing a copy of the
1744 instruction at a different address.
1746 We can't use displaced stepping when we have a signal to deliver;
1747 the comments for displaced_step_prepare explain why. The
1748 comments in the handle_inferior event for dealing with 'random
1749 signals' explain what we do instead.
1751 We can't use displaced stepping when we are waiting for vfork_done
1752 event, displaced stepping breaks the vfork child similarly as single
1753 step software breakpoint. */
1754 if (use_displaced_stepping (gdbarch)
1755 && (tp->control.trap_expected
1756 || (step && gdbarch_software_single_step_p (gdbarch)))
1757 && sig == TARGET_SIGNAL_0
1758 && !current_inferior ()->waiting_for_vfork_done)
1760 struct displaced_step_inferior_state *displaced;
1762 if (!displaced_step_prepare (inferior_ptid))
1764 /* Got placed in displaced stepping queue. Will be resumed
1765 later when all the currently queued displaced stepping
1766 requests finish. The thread is not executing at this point,
1767 and the call to set_executing will be made later. But we
1768 need to call set_running here, since from frontend point of view,
1769 the thread is running. */
1770 set_running (inferior_ptid, 1);
1771 discard_cleanups (old_cleanups);
1775 displaced = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
1776 step = gdbarch_displaced_step_hw_singlestep (gdbarch,
1777 displaced->step_closure);
1780 /* Do we need to do it the hard way, w/temp breakpoints? */
1782 step = maybe_software_singlestep (gdbarch, pc);
1784 /* Currently, our software single-step implementation leads to different
1785 results than hardware single-stepping in one situation: when stepping
1786 into delivering a signal which has an associated signal handler,
1787 hardware single-step will stop at the first instruction of the handler,
1788 while software single-step will simply skip execution of the handler.
1790 For now, this difference in behavior is accepted since there is no
1791 easy way to actually implement single-stepping into a signal handler
1792 without kernel support.
1794 However, there is one scenario where this difference leads to follow-on
1795 problems: if we're stepping off a breakpoint by removing all breakpoints
1796 and then single-stepping. In this case, the software single-step
1797 behavior means that even if there is a *breakpoint* in the signal
1798 handler, GDB still would not stop.
1800 Fortunately, we can at least fix this particular issue. We detect
1801 here the case where we are about to deliver a signal while software
1802 single-stepping with breakpoints removed. In this situation, we
1803 revert the decisions to remove all breakpoints and insert single-
1804 step breakpoints, and instead we install a step-resume breakpoint
1805 at the current address, deliver the signal without stepping, and
1806 once we arrive back at the step-resume breakpoint, actually step
1807 over the breakpoint we originally wanted to step over. */
1808 if (singlestep_breakpoints_inserted_p
1809 && tp->control.trap_expected && sig != TARGET_SIGNAL_0)
1811 /* If we have nested signals or a pending signal is delivered
1812 immediately after a handler returns, might might already have
1813 a step-resume breakpoint set on the earlier handler. We cannot
1814 set another step-resume breakpoint; just continue on until the
1815 original breakpoint is hit. */
1816 if (tp->control.step_resume_breakpoint == NULL)
1818 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
1819 tp->step_after_step_resume_breakpoint = 1;
1822 remove_single_step_breakpoints ();
1823 singlestep_breakpoints_inserted_p = 0;
1825 insert_breakpoints ();
1826 tp->control.trap_expected = 0;
1833 /* If STEP is set, it's a request to use hardware stepping
1834 facilities. But in that case, we should never
1835 use singlestep breakpoint. */
1836 gdb_assert (!(singlestep_breakpoints_inserted_p && step));
1838 /* Decide the set of threads to ask the target to resume. Start
1839 by assuming everything will be resumed, than narrow the set
1840 by applying increasingly restricting conditions. */
1841 resume_ptid = user_visible_resume_ptid (step);
1843 /* Maybe resume a single thread after all. */
1844 if (singlestep_breakpoints_inserted_p
1845 && stepping_past_singlestep_breakpoint)
1847 /* The situation here is as follows. In thread T1 we wanted to
1848 single-step. Lacking hardware single-stepping we've
1849 set breakpoint at the PC of the next instruction -- call it
1850 P. After resuming, we've hit that breakpoint in thread T2.
1851 Now we've removed original breakpoint, inserted breakpoint
1852 at P+1, and try to step to advance T2 past breakpoint.
1853 We need to step only T2, as if T1 is allowed to freely run,
1854 it can run past P, and if other threads are allowed to run,
1855 they can hit breakpoint at P+1, and nested hits of single-step
1856 breakpoints is not something we'd want -- that's complicated
1857 to support, and has no value. */
1858 resume_ptid = inferior_ptid;
1860 else if ((step || singlestep_breakpoints_inserted_p)
1861 && tp->control.trap_expected)
1863 /* We're allowing a thread to run past a breakpoint it has
1864 hit, by single-stepping the thread with the breakpoint
1865 removed. In which case, we need to single-step only this
1866 thread, and keep others stopped, as they can miss this
1867 breakpoint if allowed to run.
1869 The current code actually removes all breakpoints when
1870 doing this, not just the one being stepped over, so if we
1871 let other threads run, we can actually miss any
1872 breakpoint, not just the one at PC. */
1873 resume_ptid = inferior_ptid;
1876 if (gdbarch_cannot_step_breakpoint (gdbarch))
1878 /* Most targets can step a breakpoint instruction, thus
1879 executing it normally. But if this one cannot, just
1880 continue and we will hit it anyway. */
1881 if (step && breakpoint_inserted_here_p (aspace, pc))
1886 && use_displaced_stepping (gdbarch)
1887 && tp->control.trap_expected)
1889 struct regcache *resume_regcache = get_thread_regcache (resume_ptid);
1890 struct gdbarch *resume_gdbarch = get_regcache_arch (resume_regcache);
1891 CORE_ADDR actual_pc = regcache_read_pc (resume_regcache);
1894 fprintf_unfiltered (gdb_stdlog, "displaced: run %s: ",
1895 paddress (resume_gdbarch, actual_pc));
1896 read_memory (actual_pc, buf, sizeof (buf));
1897 displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
1900 /* Install inferior's terminal modes. */
1901 target_terminal_inferior ();
1903 /* Avoid confusing the next resume, if the next stop/resume
1904 happens to apply to another thread. */
1905 tp->suspend.stop_signal = TARGET_SIGNAL_0;
1907 /* Advise target which signals may be handled silently. If we have
1908 removed breakpoints because we are stepping over one (which can
1909 happen only if we are not using displaced stepping), we need to
1910 receive all signals to avoid accidentally skipping a breakpoint
1911 during execution of a signal handler. */
1912 if ((step || singlestep_breakpoints_inserted_p)
1913 && tp->control.trap_expected
1914 && !use_displaced_stepping (gdbarch))
1915 target_pass_signals (0, NULL);
1917 target_pass_signals ((int) TARGET_SIGNAL_LAST, signal_pass);
1919 target_resume (resume_ptid, step, sig);
1922 discard_cleanups (old_cleanups);
1927 /* Clear out all variables saying what to do when inferior is continued.
1928 First do this, then set the ones you want, then call `proceed'. */
1931 clear_proceed_status_thread (struct thread_info *tp)
1934 fprintf_unfiltered (gdb_stdlog,
1935 "infrun: clear_proceed_status_thread (%s)\n",
1936 target_pid_to_str (tp->ptid));
1938 tp->control.trap_expected = 0;
1939 tp->control.step_range_start = 0;
1940 tp->control.step_range_end = 0;
1941 tp->control.step_frame_id = null_frame_id;
1942 tp->control.step_stack_frame_id = null_frame_id;
1943 tp->control.step_over_calls = STEP_OVER_UNDEBUGGABLE;
1944 tp->stop_requested = 0;
1946 tp->control.stop_step = 0;
1948 tp->control.proceed_to_finish = 0;
1950 /* Discard any remaining commands or status from previous stop. */
1951 bpstat_clear (&tp->control.stop_bpstat);
1955 clear_proceed_status_callback (struct thread_info *tp, void *data)
1957 if (is_exited (tp->ptid))
1960 clear_proceed_status_thread (tp);
1965 clear_proceed_status (void)
1969 /* In all-stop mode, delete the per-thread status of all
1970 threads, even if inferior_ptid is null_ptid, there may be
1971 threads on the list. E.g., we may be launching a new
1972 process, while selecting the executable. */
1973 iterate_over_threads (clear_proceed_status_callback, NULL);
1976 if (!ptid_equal (inferior_ptid, null_ptid))
1978 struct inferior *inferior;
1982 /* If in non-stop mode, only delete the per-thread status of
1983 the current thread. */
1984 clear_proceed_status_thread (inferior_thread ());
1987 inferior = current_inferior ();
1988 inferior->control.stop_soon = NO_STOP_QUIETLY;
1991 stop_after_trap = 0;
1993 observer_notify_about_to_proceed ();
1997 regcache_xfree (stop_registers);
1998 stop_registers = NULL;
2002 /* Check the current thread against the thread that reported the most recent
2003 event. If a step-over is required return TRUE and set the current thread
2004 to the old thread. Otherwise return FALSE.
2006 This should be suitable for any targets that support threads. */
2009 prepare_to_proceed (int step)
2012 struct target_waitstatus wait_status;
2013 int schedlock_enabled;
2015 /* With non-stop mode on, threads are always handled individually. */
2016 gdb_assert (! non_stop);
2018 /* Get the last target status returned by target_wait(). */
2019 get_last_target_status (&wait_ptid, &wait_status);
2021 /* Make sure we were stopped at a breakpoint. */
2022 if (wait_status.kind != TARGET_WAITKIND_STOPPED
2023 || (wait_status.value.sig != TARGET_SIGNAL_TRAP
2024 && wait_status.value.sig != TARGET_SIGNAL_ILL
2025 && wait_status.value.sig != TARGET_SIGNAL_SEGV
2026 && wait_status.value.sig != TARGET_SIGNAL_EMT))
2031 schedlock_enabled = (scheduler_mode == schedlock_on
2032 || (scheduler_mode == schedlock_step
2035 /* Don't switch over to WAIT_PTID if scheduler locking is on. */
2036 if (schedlock_enabled)
2039 /* Don't switch over if we're about to resume some other process
2040 other than WAIT_PTID's, and schedule-multiple is off. */
2042 && ptid_get_pid (wait_ptid) != ptid_get_pid (inferior_ptid))
2045 /* Switched over from WAIT_PID. */
2046 if (!ptid_equal (wait_ptid, minus_one_ptid)
2047 && !ptid_equal (inferior_ptid, wait_ptid))
2049 struct regcache *regcache = get_thread_regcache (wait_ptid);
2051 if (breakpoint_here_p (get_regcache_aspace (regcache),
2052 regcache_read_pc (regcache)))
2054 /* If stepping, remember current thread to switch back to. */
2056 deferred_step_ptid = inferior_ptid;
2058 /* Switch back to WAIT_PID thread. */
2059 switch_to_thread (wait_ptid);
2062 fprintf_unfiltered (gdb_stdlog,
2063 "infrun: prepare_to_proceed (step=%d), "
2064 "switched to [%s]\n",
2065 step, target_pid_to_str (inferior_ptid));
2067 /* We return 1 to indicate that there is a breakpoint here,
2068 so we need to step over it before continuing to avoid
2069 hitting it straight away. */
2077 /* Basic routine for continuing the program in various fashions.
2079 ADDR is the address to resume at, or -1 for resume where stopped.
2080 SIGGNAL is the signal to give it, or 0 for none,
2081 or -1 for act according to how it stopped.
2082 STEP is nonzero if should trap after one instruction.
2083 -1 means return after that and print nothing.
2084 You should probably set various step_... variables
2085 before calling here, if you are stepping.
2087 You should call clear_proceed_status before calling proceed. */
2090 proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
2092 struct regcache *regcache;
2093 struct gdbarch *gdbarch;
2094 struct thread_info *tp;
2096 struct address_space *aspace;
2099 /* If we're stopped at a fork/vfork, follow the branch set by the
2100 "set follow-fork-mode" command; otherwise, we'll just proceed
2101 resuming the current thread. */
2102 if (!follow_fork ())
2104 /* The target for some reason decided not to resume. */
2106 if (target_can_async_p ())
2107 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
2111 /* We'll update this if & when we switch to a new thread. */
2112 previous_inferior_ptid = inferior_ptid;
2114 regcache = get_current_regcache ();
2115 gdbarch = get_regcache_arch (regcache);
2116 aspace = get_regcache_aspace (regcache);
2117 pc = regcache_read_pc (regcache);
2120 step_start_function = find_pc_function (pc);
2122 stop_after_trap = 1;
2124 if (addr == (CORE_ADDR) -1)
2126 if (pc == stop_pc && breakpoint_here_p (aspace, pc)
2127 && execution_direction != EXEC_REVERSE)
2128 /* There is a breakpoint at the address we will resume at,
2129 step one instruction before inserting breakpoints so that
2130 we do not stop right away (and report a second hit at this
2133 Note, we don't do this in reverse, because we won't
2134 actually be executing the breakpoint insn anyway.
2135 We'll be (un-)executing the previous instruction. */
2138 else if (gdbarch_single_step_through_delay_p (gdbarch)
2139 && gdbarch_single_step_through_delay (gdbarch,
2140 get_current_frame ()))
2141 /* We stepped onto an instruction that needs to be stepped
2142 again before re-inserting the breakpoint, do so. */
2147 regcache_write_pc (regcache, addr);
2151 fprintf_unfiltered (gdb_stdlog,
2152 "infrun: proceed (addr=%s, signal=%d, step=%d)\n",
2153 paddress (gdbarch, addr), siggnal, step);
2156 /* In non-stop, each thread is handled individually. The context
2157 must already be set to the right thread here. */
2161 /* In a multi-threaded task we may select another thread and
2162 then continue or step.
2164 But if the old thread was stopped at a breakpoint, it will
2165 immediately cause another breakpoint stop without any
2166 execution (i.e. it will report a breakpoint hit incorrectly).
2167 So we must step over it first.
2169 prepare_to_proceed checks the current thread against the
2170 thread that reported the most recent event. If a step-over
2171 is required it returns TRUE and sets the current thread to
2173 if (prepare_to_proceed (step))
2177 /* prepare_to_proceed may change the current thread. */
2178 tp = inferior_thread ();
2182 tp->control.trap_expected = 1;
2183 /* If displaced stepping is enabled, we can step over the
2184 breakpoint without hitting it, so leave all breakpoints
2185 inserted. Otherwise we need to disable all breakpoints, step
2186 one instruction, and then re-add them when that step is
2188 if (!use_displaced_stepping (gdbarch))
2189 remove_breakpoints ();
2192 /* We can insert breakpoints if we're not trying to step over one,
2193 or if we are stepping over one but we're using displaced stepping
2195 if (! tp->control.trap_expected || use_displaced_stepping (gdbarch))
2196 insert_breakpoints ();
2200 /* Pass the last stop signal to the thread we're resuming,
2201 irrespective of whether the current thread is the thread that
2202 got the last event or not. This was historically GDB's
2203 behaviour before keeping a stop_signal per thread. */
2205 struct thread_info *last_thread;
2207 struct target_waitstatus last_status;
2209 get_last_target_status (&last_ptid, &last_status);
2210 if (!ptid_equal (inferior_ptid, last_ptid)
2211 && !ptid_equal (last_ptid, null_ptid)
2212 && !ptid_equal (last_ptid, minus_one_ptid))
2214 last_thread = find_thread_ptid (last_ptid);
2217 tp->suspend.stop_signal = last_thread->suspend.stop_signal;
2218 last_thread->suspend.stop_signal = TARGET_SIGNAL_0;
2223 if (siggnal != TARGET_SIGNAL_DEFAULT)
2224 tp->suspend.stop_signal = siggnal;
2225 /* If this signal should not be seen by program,
2226 give it zero. Used for debugging signals. */
2227 else if (!signal_program[tp->suspend.stop_signal])
2228 tp->suspend.stop_signal = TARGET_SIGNAL_0;
2230 annotate_starting ();
2232 /* Make sure that output from GDB appears before output from the
2234 gdb_flush (gdb_stdout);
2236 /* Refresh prev_pc value just prior to resuming. This used to be
2237 done in stop_stepping, however, setting prev_pc there did not handle
2238 scenarios such as inferior function calls or returning from
2239 a function via the return command. In those cases, the prev_pc
2240 value was not set properly for subsequent commands. The prev_pc value
2241 is used to initialize the starting line number in the ecs. With an
2242 invalid value, the gdb next command ends up stopping at the position
2243 represented by the next line table entry past our start position.
2244 On platforms that generate one line table entry per line, this
2245 is not a problem. However, on the ia64, the compiler generates
2246 extraneous line table entries that do not increase the line number.
2247 When we issue the gdb next command on the ia64 after an inferior call
2248 or a return command, we often end up a few instructions forward, still
2249 within the original line we started.
2251 An attempt was made to refresh the prev_pc at the same time the
2252 execution_control_state is initialized (for instance, just before
2253 waiting for an inferior event). But this approach did not work
2254 because of platforms that use ptrace, where the pc register cannot
2255 be read unless the inferior is stopped. At that point, we are not
2256 guaranteed the inferior is stopped and so the regcache_read_pc() call
2257 can fail. Setting the prev_pc value here ensures the value is updated
2258 correctly when the inferior is stopped. */
2259 tp->prev_pc = regcache_read_pc (get_current_regcache ());
2261 /* Fill in with reasonable starting values. */
2262 init_thread_stepping_state (tp);
2264 /* Reset to normal state. */
2265 init_infwait_state ();
2267 /* Resume inferior. */
2268 resume (oneproc || step || bpstat_should_step (), tp->suspend.stop_signal);
2270 /* Wait for it to stop (if not standalone)
2271 and in any case decode why it stopped, and act accordingly. */
2272 /* Do this only if we are not using the event loop, or if the target
2273 does not support asynchronous execution. */
2274 if (!target_can_async_p ())
2276 wait_for_inferior ();
2282 /* Start remote-debugging of a machine over a serial link. */
2285 start_remote (int from_tty)
2287 struct inferior *inferior;
2289 inferior = current_inferior ();
2290 inferior->control.stop_soon = STOP_QUIETLY_REMOTE;
2292 /* Always go on waiting for the target, regardless of the mode. */
2293 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2294 indicate to wait_for_inferior that a target should timeout if
2295 nothing is returned (instead of just blocking). Because of this,
2296 targets expecting an immediate response need to, internally, set
2297 things up so that the target_wait() is forced to eventually
2299 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2300 differentiate to its caller what the state of the target is after
2301 the initial open has been performed. Here we're assuming that
2302 the target has stopped. It should be possible to eventually have
2303 target_open() return to the caller an indication that the target
2304 is currently running and GDB state should be set to the same as
2305 for an async run. */
2306 wait_for_inferior ();
2308 /* Now that the inferior has stopped, do any bookkeeping like
2309 loading shared libraries. We want to do this before normal_stop,
2310 so that the displayed frame is up to date. */
2311 post_create_inferior (¤t_target, from_tty);
2316 /* Initialize static vars when a new inferior begins. */
2319 init_wait_for_inferior (void)
2321 /* These are meaningless until the first time through wait_for_inferior. */
2323 breakpoint_init_inferior (inf_starting);
2325 clear_proceed_status ();
2327 stepping_past_singlestep_breakpoint = 0;
2328 deferred_step_ptid = null_ptid;
2330 target_last_wait_ptid = minus_one_ptid;
2332 previous_inferior_ptid = inferior_ptid;
2333 init_infwait_state ();
2335 /* Discard any skipped inlined frames. */
2336 clear_inline_frame_state (minus_one_ptid);
2340 /* This enum encodes possible reasons for doing a target_wait, so that
2341 wfi can call target_wait in one place. (Ultimately the call will be
2342 moved out of the infinite loop entirely.) */
2346 infwait_normal_state,
2347 infwait_thread_hop_state,
2348 infwait_step_watch_state,
2349 infwait_nonstep_watch_state
2352 /* The PTID we'll do a target_wait on.*/
2355 /* Current inferior wait state. */
2356 enum infwait_states infwait_state;
2358 /* Data to be passed around while handling an event. This data is
2359 discarded between events. */
2360 struct execution_control_state
2363 /* The thread that got the event, if this was a thread event; NULL
2365 struct thread_info *event_thread;
2367 struct target_waitstatus ws;
2369 int stop_func_filled_in;
2370 CORE_ADDR stop_func_start;
2371 CORE_ADDR stop_func_end;
2372 char *stop_func_name;
2373 int new_thread_event;
2377 static void handle_inferior_event (struct execution_control_state *ecs);
2379 static void handle_step_into_function (struct gdbarch *gdbarch,
2380 struct execution_control_state *ecs);
2381 static void handle_step_into_function_backward (struct gdbarch *gdbarch,
2382 struct execution_control_state *ecs);
2383 static void check_exception_resume (struct execution_control_state *,
2384 struct frame_info *, struct symbol *);
2386 static void stop_stepping (struct execution_control_state *ecs);
2387 static void prepare_to_wait (struct execution_control_state *ecs);
2388 static void keep_going (struct execution_control_state *ecs);
2390 /* Callback for iterate over threads. If the thread is stopped, but
2391 the user/frontend doesn't know about that yet, go through
2392 normal_stop, as if the thread had just stopped now. ARG points at
2393 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2394 ptid_is_pid(PTID) is true, applies to all threads of the process
2395 pointed at by PTID. Otherwise, apply only to the thread pointed by
2399 infrun_thread_stop_requested_callback (struct thread_info *info, void *arg)
2401 ptid_t ptid = * (ptid_t *) arg;
2403 if ((ptid_equal (info->ptid, ptid)
2404 || ptid_equal (minus_one_ptid, ptid)
2405 || (ptid_is_pid (ptid)
2406 && ptid_get_pid (ptid) == ptid_get_pid (info->ptid)))
2407 && is_running (info->ptid)
2408 && !is_executing (info->ptid))
2410 struct cleanup *old_chain;
2411 struct execution_control_state ecss;
2412 struct execution_control_state *ecs = &ecss;
2414 memset (ecs, 0, sizeof (*ecs));
2416 old_chain = make_cleanup_restore_current_thread ();
2418 switch_to_thread (info->ptid);
2420 /* Go through handle_inferior_event/normal_stop, so we always
2421 have consistent output as if the stop event had been
2423 ecs->ptid = info->ptid;
2424 ecs->event_thread = find_thread_ptid (info->ptid);
2425 ecs->ws.kind = TARGET_WAITKIND_STOPPED;
2426 ecs->ws.value.sig = TARGET_SIGNAL_0;
2428 handle_inferior_event (ecs);
2430 if (!ecs->wait_some_more)
2432 struct thread_info *tp;
2436 /* Finish off the continuations. */
2437 tp = inferior_thread ();
2438 do_all_intermediate_continuations_thread (tp, 1);
2439 do_all_continuations_thread (tp, 1);
2442 do_cleanups (old_chain);
2448 /* This function is attached as a "thread_stop_requested" observer.
2449 Cleanup local state that assumed the PTID was to be resumed, and
2450 report the stop to the frontend. */
2453 infrun_thread_stop_requested (ptid_t ptid)
2455 struct displaced_step_inferior_state *displaced;
2457 /* PTID was requested to stop. Remove it from the displaced
2458 stepping queue, so we don't try to resume it automatically. */
2460 for (displaced = displaced_step_inferior_states;
2462 displaced = displaced->next)
2464 struct displaced_step_request *it, **prev_next_p;
2466 it = displaced->step_request_queue;
2467 prev_next_p = &displaced->step_request_queue;
2470 if (ptid_match (it->ptid, ptid))
2472 *prev_next_p = it->next;
2478 prev_next_p = &it->next;
2485 iterate_over_threads (infrun_thread_stop_requested_callback, &ptid);
2489 infrun_thread_thread_exit (struct thread_info *tp, int silent)
2491 if (ptid_equal (target_last_wait_ptid, tp->ptid))
2492 nullify_last_target_wait_ptid ();
2495 /* Callback for iterate_over_threads. */
2498 delete_step_resume_breakpoint_callback (struct thread_info *info, void *data)
2500 if (is_exited (info->ptid))
2503 delete_step_resume_breakpoint (info);
2504 delete_exception_resume_breakpoint (info);
2508 /* In all-stop, delete the step resume breakpoint of any thread that
2509 had one. In non-stop, delete the step resume breakpoint of the
2510 thread that just stopped. */
2513 delete_step_thread_step_resume_breakpoint (void)
2515 if (!target_has_execution
2516 || ptid_equal (inferior_ptid, null_ptid))
2517 /* If the inferior has exited, we have already deleted the step
2518 resume breakpoints out of GDB's lists. */
2523 /* If in non-stop mode, only delete the step-resume or
2524 longjmp-resume breakpoint of the thread that just stopped
2526 struct thread_info *tp = inferior_thread ();
2528 delete_step_resume_breakpoint (tp);
2529 delete_exception_resume_breakpoint (tp);
2532 /* In all-stop mode, delete all step-resume and longjmp-resume
2533 breakpoints of any thread that had them. */
2534 iterate_over_threads (delete_step_resume_breakpoint_callback, NULL);
2537 /* A cleanup wrapper. */
2540 delete_step_thread_step_resume_breakpoint_cleanup (void *arg)
2542 delete_step_thread_step_resume_breakpoint ();
2545 /* Pretty print the results of target_wait, for debugging purposes. */
2548 print_target_wait_results (ptid_t waiton_ptid, ptid_t result_ptid,
2549 const struct target_waitstatus *ws)
2551 char *status_string = target_waitstatus_to_string (ws);
2552 struct ui_file *tmp_stream = mem_fileopen ();
2555 /* The text is split over several lines because it was getting too long.
2556 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2557 output as a unit; we want only one timestamp printed if debug_timestamp
2560 fprintf_unfiltered (tmp_stream,
2561 "infrun: target_wait (%d", PIDGET (waiton_ptid));
2562 if (PIDGET (waiton_ptid) != -1)
2563 fprintf_unfiltered (tmp_stream,
2564 " [%s]", target_pid_to_str (waiton_ptid));
2565 fprintf_unfiltered (tmp_stream, ", status) =\n");
2566 fprintf_unfiltered (tmp_stream,
2567 "infrun: %d [%s],\n",
2568 PIDGET (result_ptid), target_pid_to_str (result_ptid));
2569 fprintf_unfiltered (tmp_stream,
2573 text = ui_file_xstrdup (tmp_stream, NULL);
2575 /* This uses %s in part to handle %'s in the text, but also to avoid
2576 a gcc error: the format attribute requires a string literal. */
2577 fprintf_unfiltered (gdb_stdlog, "%s", text);
2579 xfree (status_string);
2581 ui_file_delete (tmp_stream);
2584 /* Prepare and stabilize the inferior for detaching it. E.g.,
2585 detaching while a thread is displaced stepping is a recipe for
2586 crashing it, as nothing would readjust the PC out of the scratch
2590 prepare_for_detach (void)
2592 struct inferior *inf = current_inferior ();
2593 ptid_t pid_ptid = pid_to_ptid (inf->pid);
2594 struct cleanup *old_chain_1;
2595 struct displaced_step_inferior_state *displaced;
2597 displaced = get_displaced_stepping_state (inf->pid);
2599 /* Is any thread of this process displaced stepping? If not,
2600 there's nothing else to do. */
2601 if (displaced == NULL || ptid_equal (displaced->step_ptid, null_ptid))
2605 fprintf_unfiltered (gdb_stdlog,
2606 "displaced-stepping in-process while detaching");
2608 old_chain_1 = make_cleanup_restore_integer (&inf->detaching);
2611 while (!ptid_equal (displaced->step_ptid, null_ptid))
2613 struct cleanup *old_chain_2;
2614 struct execution_control_state ecss;
2615 struct execution_control_state *ecs;
2618 memset (ecs, 0, sizeof (*ecs));
2620 overlay_cache_invalid = 1;
2622 if (deprecated_target_wait_hook)
2623 ecs->ptid = deprecated_target_wait_hook (pid_ptid, &ecs->ws, 0);
2625 ecs->ptid = target_wait (pid_ptid, &ecs->ws, 0);
2628 print_target_wait_results (pid_ptid, ecs->ptid, &ecs->ws);
2630 /* If an error happens while handling the event, propagate GDB's
2631 knowledge of the executing state to the frontend/user running
2633 old_chain_2 = make_cleanup (finish_thread_state_cleanup,
2636 /* In non-stop mode, each thread is handled individually.
2637 Switch early, so the global state is set correctly for this
2640 && ecs->ws.kind != TARGET_WAITKIND_EXITED
2641 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
2642 context_switch (ecs->ptid);
2644 /* Now figure out what to do with the result of the result. */
2645 handle_inferior_event (ecs);
2647 /* No error, don't finish the state yet. */
2648 discard_cleanups (old_chain_2);
2650 /* Breakpoints and watchpoints are not installed on the target
2651 at this point, and signals are passed directly to the
2652 inferior, so this must mean the process is gone. */
2653 if (!ecs->wait_some_more)
2655 discard_cleanups (old_chain_1);
2656 error (_("Program exited while detaching"));
2660 discard_cleanups (old_chain_1);
2663 /* Wait for control to return from inferior to debugger.
2665 If inferior gets a signal, we may decide to start it up again
2666 instead of returning. That is why there is a loop in this function.
2667 When this function actually returns it means the inferior
2668 should be left stopped and GDB should read more commands. */
2671 wait_for_inferior (void)
2673 struct cleanup *old_cleanups;
2674 struct execution_control_state ecss;
2675 struct execution_control_state *ecs;
2679 (gdb_stdlog, "infrun: wait_for_inferior ()\n");
2682 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup, NULL);
2685 memset (ecs, 0, sizeof (*ecs));
2689 struct cleanup *old_chain;
2691 overlay_cache_invalid = 1;
2693 if (deprecated_target_wait_hook)
2694 ecs->ptid = deprecated_target_wait_hook (waiton_ptid, &ecs->ws, 0);
2696 ecs->ptid = target_wait (waiton_ptid, &ecs->ws, 0);
2699 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
2701 /* If an error happens while handling the event, propagate GDB's
2702 knowledge of the executing state to the frontend/user running
2704 old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
2706 if (ecs->ws.kind == TARGET_WAITKIND_SYSCALL_ENTRY
2707 || ecs->ws.kind == TARGET_WAITKIND_SYSCALL_RETURN)
2708 ecs->ws.value.syscall_number = UNKNOWN_SYSCALL;
2710 /* Now figure out what to do with the result of the result. */
2711 handle_inferior_event (ecs);
2713 /* No error, don't finish the state yet. */
2714 discard_cleanups (old_chain);
2716 if (!ecs->wait_some_more)
2720 do_cleanups (old_cleanups);
2723 /* Asynchronous version of wait_for_inferior. It is called by the
2724 event loop whenever a change of state is detected on the file
2725 descriptor corresponding to the target. It can be called more than
2726 once to complete a single execution command. In such cases we need
2727 to keep the state in a global variable ECSS. If it is the last time
2728 that this function is called for a single execution command, then
2729 report to the user that the inferior has stopped, and do the
2730 necessary cleanups. */
2733 fetch_inferior_event (void *client_data)
2735 struct execution_control_state ecss;
2736 struct execution_control_state *ecs = &ecss;
2737 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
2738 struct cleanup *ts_old_chain;
2739 int was_sync = sync_execution;
2742 memset (ecs, 0, sizeof (*ecs));
2744 /* We're handling a live event, so make sure we're doing live
2745 debugging. If we're looking at traceframes while the target is
2746 running, we're going to need to get back to that mode after
2747 handling the event. */
2750 make_cleanup_restore_current_traceframe ();
2751 set_current_traceframe (-1);
2755 /* In non-stop mode, the user/frontend should not notice a thread
2756 switch due to internal events. Make sure we reverse to the
2757 user selected thread and frame after handling the event and
2758 running any breakpoint commands. */
2759 make_cleanup_restore_current_thread ();
2761 overlay_cache_invalid = 1;
2763 make_cleanup_restore_integer (&execution_direction);
2764 execution_direction = target_execution_direction ();
2766 if (deprecated_target_wait_hook)
2768 deprecated_target_wait_hook (waiton_ptid, &ecs->ws, TARGET_WNOHANG);
2770 ecs->ptid = target_wait (waiton_ptid, &ecs->ws, TARGET_WNOHANG);
2773 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
2776 && ecs->ws.kind != TARGET_WAITKIND_IGNORE
2777 && ecs->ws.kind != TARGET_WAITKIND_NO_RESUMED
2778 && ecs->ws.kind != TARGET_WAITKIND_EXITED
2779 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
2780 /* In non-stop mode, each thread is handled individually. Switch
2781 early, so the global state is set correctly for this
2783 context_switch (ecs->ptid);
2785 /* If an error happens while handling the event, propagate GDB's
2786 knowledge of the executing state to the frontend/user running
2789 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
2791 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &ecs->ptid);
2793 /* Get executed before make_cleanup_restore_current_thread above to apply
2794 still for the thread which has thrown the exception. */
2795 make_bpstat_clear_actions_cleanup ();
2797 /* Now figure out what to do with the result of the result. */
2798 handle_inferior_event (ecs);
2800 if (!ecs->wait_some_more)
2802 struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
2804 delete_step_thread_step_resume_breakpoint ();
2806 /* We may not find an inferior if this was a process exit. */
2807 if (inf == NULL || inf->control.stop_soon == NO_STOP_QUIETLY)
2810 if (target_has_execution
2811 && ecs->ws.kind != TARGET_WAITKIND_NO_RESUMED
2812 && ecs->ws.kind != TARGET_WAITKIND_EXITED
2813 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
2814 && ecs->event_thread->step_multi
2815 && ecs->event_thread->control.stop_step)
2816 inferior_event_handler (INF_EXEC_CONTINUE, NULL);
2819 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
2824 /* No error, don't finish the thread states yet. */
2825 discard_cleanups (ts_old_chain);
2827 /* Revert thread and frame. */
2828 do_cleanups (old_chain);
2830 /* If the inferior was in sync execution mode, and now isn't,
2831 restore the prompt (a synchronous execution command has finished,
2832 and we're ready for input). */
2833 if (interpreter_async && was_sync && !sync_execution)
2834 display_gdb_prompt (0);
2838 && exec_done_display_p
2839 && (ptid_equal (inferior_ptid, null_ptid)
2840 || !is_running (inferior_ptid)))
2841 printf_unfiltered (_("completed.\n"));
2844 /* Record the frame and location we're currently stepping through. */
2846 set_step_info (struct frame_info *frame, struct symtab_and_line sal)
2848 struct thread_info *tp = inferior_thread ();
2850 tp->control.step_frame_id = get_frame_id (frame);
2851 tp->control.step_stack_frame_id = get_stack_frame_id (frame);
2853 tp->current_symtab = sal.symtab;
2854 tp->current_line = sal.line;
2857 /* Clear context switchable stepping state. */
2860 init_thread_stepping_state (struct thread_info *tss)
2862 tss->stepping_over_breakpoint = 0;
2863 tss->step_after_step_resume_breakpoint = 0;
2866 /* Return the cached copy of the last pid/waitstatus returned by
2867 target_wait()/deprecated_target_wait_hook(). The data is actually
2868 cached by handle_inferior_event(), which gets called immediately
2869 after target_wait()/deprecated_target_wait_hook(). */
2872 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
2874 *ptidp = target_last_wait_ptid;
2875 *status = target_last_waitstatus;
2879 nullify_last_target_wait_ptid (void)
2881 target_last_wait_ptid = minus_one_ptid;
2884 /* Switch thread contexts. */
2887 context_switch (ptid_t ptid)
2889 if (debug_infrun && !ptid_equal (ptid, inferior_ptid))
2891 fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ",
2892 target_pid_to_str (inferior_ptid));
2893 fprintf_unfiltered (gdb_stdlog, "to %s\n",
2894 target_pid_to_str (ptid));
2897 switch_to_thread (ptid);
2901 adjust_pc_after_break (struct execution_control_state *ecs)
2903 struct regcache *regcache;
2904 struct gdbarch *gdbarch;
2905 struct address_space *aspace;
2906 CORE_ADDR breakpoint_pc;
2908 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2909 we aren't, just return.
2911 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2912 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2913 implemented by software breakpoints should be handled through the normal
2916 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2917 different signals (SIGILL or SIGEMT for instance), but it is less
2918 clear where the PC is pointing afterwards. It may not match
2919 gdbarch_decr_pc_after_break. I don't know any specific target that
2920 generates these signals at breakpoints (the code has been in GDB since at
2921 least 1992) so I can not guess how to handle them here.
2923 In earlier versions of GDB, a target with
2924 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2925 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2926 target with both of these set in GDB history, and it seems unlikely to be
2927 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2929 if (ecs->ws.kind != TARGET_WAITKIND_STOPPED)
2932 if (ecs->ws.value.sig != TARGET_SIGNAL_TRAP)
2935 /* In reverse execution, when a breakpoint is hit, the instruction
2936 under it has already been de-executed. The reported PC always
2937 points at the breakpoint address, so adjusting it further would
2938 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2941 B1 0x08000000 : INSN1
2942 B2 0x08000001 : INSN2
2944 PC -> 0x08000003 : INSN4
2946 Say you're stopped at 0x08000003 as above. Reverse continuing
2947 from that point should hit B2 as below. Reading the PC when the
2948 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2949 been de-executed already.
2951 B1 0x08000000 : INSN1
2952 B2 PC -> 0x08000001 : INSN2
2956 We can't apply the same logic as for forward execution, because
2957 we would wrongly adjust the PC to 0x08000000, since there's a
2958 breakpoint at PC - 1. We'd then report a hit on B1, although
2959 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2961 if (execution_direction == EXEC_REVERSE)
2964 /* If this target does not decrement the PC after breakpoints, then
2965 we have nothing to do. */
2966 regcache = get_thread_regcache (ecs->ptid);
2967 gdbarch = get_regcache_arch (regcache);
2968 if (gdbarch_decr_pc_after_break (gdbarch) == 0)
2971 aspace = get_regcache_aspace (regcache);
2973 /* Find the location where (if we've hit a breakpoint) the
2974 breakpoint would be. */
2975 breakpoint_pc = regcache_read_pc (regcache)
2976 - gdbarch_decr_pc_after_break (gdbarch);
2978 /* Check whether there actually is a software breakpoint inserted at
2981 If in non-stop mode, a race condition is possible where we've
2982 removed a breakpoint, but stop events for that breakpoint were
2983 already queued and arrive later. To suppress those spurious
2984 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
2985 and retire them after a number of stop events are reported. */
2986 if (software_breakpoint_inserted_here_p (aspace, breakpoint_pc)
2987 || (non_stop && moribund_breakpoint_here_p (aspace, breakpoint_pc)))
2989 struct cleanup *old_cleanups = NULL;
2992 old_cleanups = record_gdb_operation_disable_set ();
2994 /* When using hardware single-step, a SIGTRAP is reported for both
2995 a completed single-step and a software breakpoint. Need to
2996 differentiate between the two, as the latter needs adjusting
2997 but the former does not.
2999 The SIGTRAP can be due to a completed hardware single-step only if
3000 - we didn't insert software single-step breakpoints
3001 - the thread to be examined is still the current thread
3002 - this thread is currently being stepped
3004 If any of these events did not occur, we must have stopped due
3005 to hitting a software breakpoint, and have to back up to the
3008 As a special case, we could have hardware single-stepped a
3009 software breakpoint. In this case (prev_pc == breakpoint_pc),
3010 we also need to back up to the breakpoint address. */
3012 if (singlestep_breakpoints_inserted_p
3013 || !ptid_equal (ecs->ptid, inferior_ptid)
3014 || !currently_stepping (ecs->event_thread)
3015 || ecs->event_thread->prev_pc == breakpoint_pc)
3016 regcache_write_pc (regcache, breakpoint_pc);
3019 do_cleanups (old_cleanups);
3024 init_infwait_state (void)
3026 waiton_ptid = pid_to_ptid (-1);
3027 infwait_state = infwait_normal_state;
3031 error_is_running (void)
3033 error (_("Cannot execute this command while "
3034 "the selected thread is running."));
3038 ensure_not_running (void)
3040 if (is_running (inferior_ptid))
3041 error_is_running ();
3045 stepped_in_from (struct frame_info *frame, struct frame_id step_frame_id)
3047 for (frame = get_prev_frame (frame);
3049 frame = get_prev_frame (frame))
3051 if (frame_id_eq (get_frame_id (frame), step_frame_id))
3053 if (get_frame_type (frame) != INLINE_FRAME)
3060 /* Auxiliary function that handles syscall entry/return events.
3061 It returns 1 if the inferior should keep going (and GDB
3062 should ignore the event), or 0 if the event deserves to be
3066 handle_syscall_event (struct execution_control_state *ecs)
3068 struct regcache *regcache;
3069 struct gdbarch *gdbarch;
3072 if (!ptid_equal (ecs->ptid, inferior_ptid))
3073 context_switch (ecs->ptid);
3075 regcache = get_thread_regcache (ecs->ptid);
3076 gdbarch = get_regcache_arch (regcache);
3077 syscall_number = gdbarch_get_syscall_number (gdbarch, ecs->ptid);
3078 stop_pc = regcache_read_pc (regcache);
3080 target_last_waitstatus.value.syscall_number = syscall_number;
3082 if (catch_syscall_enabled () > 0
3083 && catching_syscall_number (syscall_number) > 0)
3086 fprintf_unfiltered (gdb_stdlog, "infrun: syscall number = '%d'\n",
3089 ecs->event_thread->control.stop_bpstat
3090 = bpstat_stop_status (get_regcache_aspace (regcache),
3091 stop_pc, ecs->ptid);
3093 = !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat);
3095 if (!ecs->random_signal)
3097 /* Catchpoint hit. */
3098 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_TRAP;
3103 /* If no catchpoint triggered for this, then keep going. */
3104 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
3109 /* Clear the supplied execution_control_state's stop_func_* fields. */
3112 clear_stop_func (struct execution_control_state *ecs)
3114 ecs->stop_func_filled_in = 0;
3115 ecs->stop_func_start = 0;
3116 ecs->stop_func_end = 0;
3117 ecs->stop_func_name = NULL;
3120 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3123 fill_in_stop_func (struct gdbarch *gdbarch,
3124 struct execution_control_state *ecs)
3126 if (!ecs->stop_func_filled_in)
3128 /* Don't care about return value; stop_func_start and stop_func_name
3129 will both be 0 if it doesn't work. */
3130 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
3131 &ecs->stop_func_start, &ecs->stop_func_end);
3132 ecs->stop_func_start
3133 += gdbarch_deprecated_function_start_offset (gdbarch);
3135 ecs->stop_func_filled_in = 1;
3139 /* Given an execution control state that has been freshly filled in
3140 by an event from the inferior, figure out what it means and take
3141 appropriate action. */
3144 handle_inferior_event (struct execution_control_state *ecs)
3146 struct frame_info *frame;
3147 struct gdbarch *gdbarch;
3148 int stopped_by_watchpoint;
3149 int stepped_after_stopped_by_watchpoint = 0;
3150 struct symtab_and_line stop_pc_sal;
3151 enum stop_kind stop_soon;
3153 if (ecs->ws.kind == TARGET_WAITKIND_IGNORE)
3155 /* We had an event in the inferior, but we are not interested in
3156 handling it at this level. The lower layers have already
3157 done what needs to be done, if anything.
3159 One of the possible circumstances for this is when the
3160 inferior produces output for the console. The inferior has
3161 not stopped, and we are ignoring the event. Another possible
3162 circumstance is any event which the lower level knows will be
3163 reported multiple times without an intervening resume. */
3165 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n");
3166 prepare_to_wait (ecs);
3170 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED
3171 && target_can_async_p () && !sync_execution)
3173 /* There were no unwaited-for children left in the target, but,
3174 we're not synchronously waiting for events either. Just
3175 ignore. Otherwise, if we were running a synchronous
3176 execution command, we need to cancel it and give the user
3177 back the terminal. */
3179 fprintf_unfiltered (gdb_stdlog,
3180 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3181 prepare_to_wait (ecs);
3185 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
3186 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
3187 && ecs->ws.kind != TARGET_WAITKIND_NO_RESUMED)
3189 struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
3192 stop_soon = inf->control.stop_soon;
3195 stop_soon = NO_STOP_QUIETLY;
3197 /* Cache the last pid/waitstatus. */
3198 target_last_wait_ptid = ecs->ptid;
3199 target_last_waitstatus = ecs->ws;
3201 /* Always clear state belonging to the previous time we stopped. */
3202 stop_stack_dummy = STOP_NONE;
3204 if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED)
3206 /* No unwaited-for children left. IOW, all resumed children
3209 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3211 stop_print_frame = 0;
3212 stop_stepping (ecs);
3216 /* If it's a new process, add it to the thread database. */
3218 ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid)
3219 && !ptid_equal (ecs->ptid, minus_one_ptid)
3220 && !in_thread_list (ecs->ptid));
3222 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
3223 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event)
3224 add_thread (ecs->ptid);
3226 ecs->event_thread = find_thread_ptid (ecs->ptid);
3228 /* Dependent on valid ECS->EVENT_THREAD. */
3229 adjust_pc_after_break (ecs);
3231 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3232 reinit_frame_cache ();
3234 breakpoint_retire_moribund ();
3236 /* First, distinguish signals caused by the debugger from signals
3237 that have to do with the program's own actions. Note that
3238 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3239 on the operating system version. Here we detect when a SIGILL or
3240 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3241 something similar for SIGSEGV, since a SIGSEGV will be generated
3242 when we're trying to execute a breakpoint instruction on a
3243 non-executable stack. This happens for call dummy breakpoints
3244 for architectures like SPARC that place call dummies on the
3246 if (ecs->ws.kind == TARGET_WAITKIND_STOPPED
3247 && (ecs->ws.value.sig == TARGET_SIGNAL_ILL
3248 || ecs->ws.value.sig == TARGET_SIGNAL_SEGV
3249 || ecs->ws.value.sig == TARGET_SIGNAL_EMT))
3251 struct regcache *regcache = get_thread_regcache (ecs->ptid);
3253 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache),
3254 regcache_read_pc (regcache)))
3257 fprintf_unfiltered (gdb_stdlog,
3258 "infrun: Treating signal as SIGTRAP\n");
3259 ecs->ws.value.sig = TARGET_SIGNAL_TRAP;
3263 /* Mark the non-executing threads accordingly. In all-stop, all
3264 threads of all processes are stopped when we get any event
3265 reported. In non-stop mode, only the event thread stops. If
3266 we're handling a process exit in non-stop mode, there's nothing
3267 to do, as threads of the dead process are gone, and threads of
3268 any other process were left running. */
3270 set_executing (minus_one_ptid, 0);
3271 else if (ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
3272 && ecs->ws.kind != TARGET_WAITKIND_EXITED)
3273 set_executing (ecs->ptid, 0);
3275 switch (infwait_state)
3277 case infwait_thread_hop_state:
3279 fprintf_unfiltered (gdb_stdlog, "infrun: infwait_thread_hop_state\n");
3282 case infwait_normal_state:
3284 fprintf_unfiltered (gdb_stdlog, "infrun: infwait_normal_state\n");
3287 case infwait_step_watch_state:
3289 fprintf_unfiltered (gdb_stdlog,
3290 "infrun: infwait_step_watch_state\n");
3292 stepped_after_stopped_by_watchpoint = 1;
3295 case infwait_nonstep_watch_state:
3297 fprintf_unfiltered (gdb_stdlog,
3298 "infrun: infwait_nonstep_watch_state\n");
3299 insert_breakpoints ();
3301 /* FIXME-maybe: is this cleaner than setting a flag? Does it
3302 handle things like signals arriving and other things happening
3303 in combination correctly? */
3304 stepped_after_stopped_by_watchpoint = 1;
3308 internal_error (__FILE__, __LINE__, _("bad switch"));
3311 infwait_state = infwait_normal_state;
3312 waiton_ptid = pid_to_ptid (-1);
3314 switch (ecs->ws.kind)
3316 case TARGET_WAITKIND_LOADED:
3318 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n");
3319 /* Ignore gracefully during startup of the inferior, as it might
3320 be the shell which has just loaded some objects, otherwise
3321 add the symbols for the newly loaded objects. Also ignore at
3322 the beginning of an attach or remote session; we will query
3323 the full list of libraries once the connection is
3325 if (stop_soon == NO_STOP_QUIETLY)
3327 /* Check for any newly added shared libraries if we're
3328 supposed to be adding them automatically. Switch
3329 terminal for any messages produced by
3330 breakpoint_re_set. */
3331 target_terminal_ours_for_output ();
3332 /* NOTE: cagney/2003-11-25: Make certain that the target
3333 stack's section table is kept up-to-date. Architectures,
3334 (e.g., PPC64), use the section table to perform
3335 operations such as address => section name and hence
3336 require the table to contain all sections (including
3337 those found in shared libraries). */
3339 SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
3341 solib_add (NULL, 0, ¤t_target, auto_solib_add);
3343 target_terminal_inferior ();
3345 /* If requested, stop when the dynamic linker notifies
3346 gdb of events. This allows the user to get control
3347 and place breakpoints in initializer routines for
3348 dynamically loaded objects (among other things). */
3349 if (stop_on_solib_events)
3351 /* Make sure we print "Stopped due to solib-event" in
3353 stop_print_frame = 1;
3355 stop_stepping (ecs);
3359 /* NOTE drow/2007-05-11: This might be a good place to check
3360 for "catch load". */
3363 /* If we are skipping through a shell, or through shared library
3364 loading that we aren't interested in, resume the program. If
3365 we're running the program normally, also resume. But stop if
3366 we're attaching or setting up a remote connection. */
3367 if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY)
3369 /* Loading of shared libraries might have changed breakpoint
3370 addresses. Make sure new breakpoints are inserted. */
3371 if (stop_soon == NO_STOP_QUIETLY
3372 && !breakpoints_always_inserted_mode ())
3373 insert_breakpoints ();
3374 resume (0, TARGET_SIGNAL_0);
3375 prepare_to_wait (ecs);
3381 case TARGET_WAITKIND_SPURIOUS:
3383 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3384 resume (0, TARGET_SIGNAL_0);
3385 prepare_to_wait (ecs);
3388 case TARGET_WAITKIND_EXITED:
3390 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXITED\n");
3391 inferior_ptid = ecs->ptid;
3392 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs->ptid)));
3393 set_current_program_space (current_inferior ()->pspace);
3394 handle_vfork_child_exec_or_exit (0);
3395 target_terminal_ours (); /* Must do this before mourn anyway. */
3396 print_exited_reason (ecs->ws.value.integer);
3398 /* Record the exit code in the convenience variable $_exitcode, so
3399 that the user can inspect this again later. */
3400 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3401 (LONGEST) ecs->ws.value.integer);
3403 /* Also record this in the inferior itself. */
3404 current_inferior ()->has_exit_code = 1;
3405 current_inferior ()->exit_code = (LONGEST) ecs->ws.value.integer;
3407 gdb_flush (gdb_stdout);
3408 target_mourn_inferior ();
3409 singlestep_breakpoints_inserted_p = 0;
3410 cancel_single_step_breakpoints ();
3411 stop_print_frame = 0;
3412 stop_stepping (ecs);
3415 case TARGET_WAITKIND_SIGNALLED:
3417 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SIGNALLED\n");
3418 inferior_ptid = ecs->ptid;
3419 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs->ptid)));
3420 set_current_program_space (current_inferior ()->pspace);
3421 handle_vfork_child_exec_or_exit (0);
3422 stop_print_frame = 0;
3423 target_terminal_ours (); /* Must do this before mourn anyway. */
3425 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
3426 reach here unless the inferior is dead. However, for years
3427 target_kill() was called here, which hints that fatal signals aren't
3428 really fatal on some systems. If that's true, then some changes
3430 target_mourn_inferior ();
3432 print_signal_exited_reason (ecs->ws.value.sig);
3433 singlestep_breakpoints_inserted_p = 0;
3434 cancel_single_step_breakpoints ();
3435 stop_stepping (ecs);
3438 /* The following are the only cases in which we keep going;
3439 the above cases end in a continue or goto. */
3440 case TARGET_WAITKIND_FORKED:
3441 case TARGET_WAITKIND_VFORKED:
3443 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
3445 /* Check whether the inferior is displaced stepping. */
3447 struct regcache *regcache = get_thread_regcache (ecs->ptid);
3448 struct gdbarch *gdbarch = get_regcache_arch (regcache);
3449 struct displaced_step_inferior_state *displaced
3450 = get_displaced_stepping_state (ptid_get_pid (ecs->ptid));
3452 /* If checking displaced stepping is supported, and thread
3453 ecs->ptid is displaced stepping. */
3454 if (displaced && ptid_equal (displaced->step_ptid, ecs->ptid))
3456 struct inferior *parent_inf
3457 = find_inferior_pid (ptid_get_pid (ecs->ptid));
3458 struct regcache *child_regcache;
3459 CORE_ADDR parent_pc;
3461 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3462 indicating that the displaced stepping of syscall instruction
3463 has been done. Perform cleanup for parent process here. Note
3464 that this operation also cleans up the child process for vfork,
3465 because their pages are shared. */
3466 displaced_step_fixup (ecs->ptid, TARGET_SIGNAL_TRAP);
3468 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
3470 /* Restore scratch pad for child process. */
3471 displaced_step_restore (displaced, ecs->ws.value.related_pid);
3474 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3475 the child's PC is also within the scratchpad. Set the child's PC
3476 to the parent's PC value, which has already been fixed up.
3477 FIXME: we use the parent's aspace here, although we're touching
3478 the child, because the child hasn't been added to the inferior
3479 list yet at this point. */
3482 = get_thread_arch_aspace_regcache (ecs->ws.value.related_pid,
3484 parent_inf->aspace);
3485 /* Read PC value of parent process. */
3486 parent_pc = regcache_read_pc (regcache);
3488 if (debug_displaced)
3489 fprintf_unfiltered (gdb_stdlog,
3490 "displaced: write child pc from %s to %s\n",
3492 regcache_read_pc (child_regcache)),
3493 paddress (gdbarch, parent_pc));
3495 regcache_write_pc (child_regcache, parent_pc);
3499 if (!ptid_equal (ecs->ptid, inferior_ptid))
3501 context_switch (ecs->ptid);
3502 reinit_frame_cache ();
3505 /* Immediately detach breakpoints from the child before there's
3506 any chance of letting the user delete breakpoints from the
3507 breakpoint lists. If we don't do this early, it's easy to
3508 leave left over traps in the child, vis: "break foo; catch
3509 fork; c; <fork>; del; c; <child calls foo>". We only follow
3510 the fork on the last `continue', and by that time the
3511 breakpoint at "foo" is long gone from the breakpoint table.
3512 If we vforked, then we don't need to unpatch here, since both
3513 parent and child are sharing the same memory pages; we'll
3514 need to unpatch at follow/detach time instead to be certain
3515 that new breakpoints added between catchpoint hit time and
3516 vfork follow are detached. */
3517 if (ecs->ws.kind != TARGET_WAITKIND_VFORKED)
3519 int child_pid = ptid_get_pid (ecs->ws.value.related_pid);
3521 /* This won't actually modify the breakpoint list, but will
3522 physically remove the breakpoints from the child. */
3523 detach_breakpoints (child_pid);
3526 if (singlestep_breakpoints_inserted_p)
3528 /* Pull the single step breakpoints out of the target. */
3529 remove_single_step_breakpoints ();
3530 singlestep_breakpoints_inserted_p = 0;
3533 /* In case the event is caught by a catchpoint, remember that
3534 the event is to be followed at the next resume of the thread,
3535 and not immediately. */
3536 ecs->event_thread->pending_follow = ecs->ws;
3538 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3540 ecs->event_thread->control.stop_bpstat
3541 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3542 stop_pc, ecs->ptid);
3544 /* Note that we're interested in knowing the bpstat actually
3545 causes a stop, not just if it may explain the signal.
3546 Software watchpoints, for example, always appear in the
3549 = !bpstat_causes_stop (ecs->event_thread->control.stop_bpstat);
3551 /* If no catchpoint triggered for this, then keep going. */
3552 if (ecs->random_signal)
3558 = (follow_fork_mode_string == follow_fork_mode_child);
3560 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
3562 should_resume = follow_fork ();
3565 child = ecs->ws.value.related_pid;
3567 /* In non-stop mode, also resume the other branch. */
3568 if (non_stop && !detach_fork)
3571 switch_to_thread (parent);
3573 switch_to_thread (child);
3575 ecs->event_thread = inferior_thread ();
3576 ecs->ptid = inferior_ptid;
3581 switch_to_thread (child);
3583 switch_to_thread (parent);
3585 ecs->event_thread = inferior_thread ();
3586 ecs->ptid = inferior_ptid;
3591 stop_stepping (ecs);
3594 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_TRAP;
3595 goto process_event_stop_test;
3597 case TARGET_WAITKIND_VFORK_DONE:
3598 /* Done with the shared memory region. Re-insert breakpoints in
3599 the parent, and keep going. */
3602 fprintf_unfiltered (gdb_stdlog,
3603 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3605 if (!ptid_equal (ecs->ptid, inferior_ptid))
3606 context_switch (ecs->ptid);
3608 current_inferior ()->waiting_for_vfork_done = 0;
3609 current_inferior ()->pspace->breakpoints_not_allowed = 0;
3610 /* This also takes care of reinserting breakpoints in the
3611 previously locked inferior. */
3615 case TARGET_WAITKIND_EXECD:
3617 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n");
3619 if (!ptid_equal (ecs->ptid, inferior_ptid))
3621 context_switch (ecs->ptid);
3622 reinit_frame_cache ();
3625 singlestep_breakpoints_inserted_p = 0;
3626 cancel_single_step_breakpoints ();
3628 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3630 /* Do whatever is necessary to the parent branch of the vfork. */
3631 handle_vfork_child_exec_or_exit (1);
3633 /* This causes the eventpoints and symbol table to be reset.
3634 Must do this now, before trying to determine whether to
3636 follow_exec (inferior_ptid, ecs->ws.value.execd_pathname);
3638 ecs->event_thread->control.stop_bpstat
3639 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3640 stop_pc, ecs->ptid);
3642 = !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat);
3644 /* Note that this may be referenced from inside
3645 bpstat_stop_status above, through inferior_has_execd. */
3646 xfree (ecs->ws.value.execd_pathname);
3647 ecs->ws.value.execd_pathname = NULL;
3649 /* If no catchpoint triggered for this, then keep going. */
3650 if (ecs->random_signal)
3652 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
3656 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_TRAP;
3657 goto process_event_stop_test;
3659 /* Be careful not to try to gather much state about a thread
3660 that's in a syscall. It's frequently a losing proposition. */
3661 case TARGET_WAITKIND_SYSCALL_ENTRY:
3663 fprintf_unfiltered (gdb_stdlog,
3664 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3665 /* Getting the current syscall number. */
3666 if (handle_syscall_event (ecs) != 0)
3668 goto process_event_stop_test;
3670 /* Before examining the threads further, step this thread to
3671 get it entirely out of the syscall. (We get notice of the
3672 event when the thread is just on the verge of exiting a
3673 syscall. Stepping one instruction seems to get it back
3675 case TARGET_WAITKIND_SYSCALL_RETURN:
3677 fprintf_unfiltered (gdb_stdlog,
3678 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3679 if (handle_syscall_event (ecs) != 0)
3681 goto process_event_stop_test;
3683 case TARGET_WAITKIND_STOPPED:
3685 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n");
3686 ecs->event_thread->suspend.stop_signal = ecs->ws.value.sig;
3689 case TARGET_WAITKIND_NO_HISTORY:
3691 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
3692 /* Reverse execution: target ran out of history info. */
3693 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3694 print_no_history_reason ();
3695 stop_stepping (ecs);
3699 if (ecs->new_thread_event)
3702 /* Non-stop assumes that the target handles adding new threads
3703 to the thread list. */
3704 internal_error (__FILE__, __LINE__,
3705 "targets should add new threads to the thread "
3706 "list themselves in non-stop mode.");
3708 /* We may want to consider not doing a resume here in order to
3709 give the user a chance to play with the new thread. It might
3710 be good to make that a user-settable option. */
3712 /* At this point, all threads are stopped (happens automatically
3713 in either the OS or the native code). Therefore we need to
3714 continue all threads in order to make progress. */
3716 if (!ptid_equal (ecs->ptid, inferior_ptid))
3717 context_switch (ecs->ptid);
3718 target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
3719 prepare_to_wait (ecs);
3723 if (ecs->ws.kind == TARGET_WAITKIND_STOPPED)
3725 /* Do we need to clean up the state of a thread that has
3726 completed a displaced single-step? (Doing so usually affects
3727 the PC, so do it here, before we set stop_pc.) */
3728 displaced_step_fixup (ecs->ptid,
3729 ecs->event_thread->suspend.stop_signal);
3731 /* If we either finished a single-step or hit a breakpoint, but
3732 the user wanted this thread to be stopped, pretend we got a
3733 SIG0 (generic unsignaled stop). */
3735 if (ecs->event_thread->stop_requested
3736 && ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP)
3737 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
3740 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3744 struct regcache *regcache = get_thread_regcache (ecs->ptid);
3745 struct gdbarch *gdbarch = get_regcache_arch (regcache);
3746 struct cleanup *old_chain = save_inferior_ptid ();
3748 inferior_ptid = ecs->ptid;
3750 fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = %s\n",
3751 paddress (gdbarch, stop_pc));
3752 if (target_stopped_by_watchpoint ())
3756 fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n");
3758 if (target_stopped_data_address (¤t_target, &addr))
3759 fprintf_unfiltered (gdb_stdlog,
3760 "infrun: stopped data address = %s\n",
3761 paddress (gdbarch, addr));
3763 fprintf_unfiltered (gdb_stdlog,
3764 "infrun: (no data address available)\n");
3767 do_cleanups (old_chain);
3770 if (stepping_past_singlestep_breakpoint)
3772 gdb_assert (singlestep_breakpoints_inserted_p);
3773 gdb_assert (ptid_equal (singlestep_ptid, ecs->ptid));
3774 gdb_assert (!ptid_equal (singlestep_ptid, saved_singlestep_ptid));
3776 stepping_past_singlestep_breakpoint = 0;
3778 /* We've either finished single-stepping past the single-step
3779 breakpoint, or stopped for some other reason. It would be nice if
3780 we could tell, but we can't reliably. */
3781 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP)
3784 fprintf_unfiltered (gdb_stdlog,
3785 "infrun: stepping_past_"
3786 "singlestep_breakpoint\n");
3787 /* Pull the single step breakpoints out of the target. */
3788 remove_single_step_breakpoints ();
3789 singlestep_breakpoints_inserted_p = 0;
3791 ecs->random_signal = 0;
3792 ecs->event_thread->control.trap_expected = 0;
3794 context_switch (saved_singlestep_ptid);
3795 if (deprecated_context_hook)
3796 deprecated_context_hook (pid_to_thread_id (ecs->ptid));
3798 resume (1, TARGET_SIGNAL_0);
3799 prepare_to_wait (ecs);
3804 if (!ptid_equal (deferred_step_ptid, null_ptid))
3806 /* In non-stop mode, there's never a deferred_step_ptid set. */
3807 gdb_assert (!non_stop);
3809 /* If we stopped for some other reason than single-stepping, ignore
3810 the fact that we were supposed to switch back. */
3811 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP)
3814 fprintf_unfiltered (gdb_stdlog,
3815 "infrun: handling deferred step\n");
3817 /* Pull the single step breakpoints out of the target. */
3818 if (singlestep_breakpoints_inserted_p)
3820 remove_single_step_breakpoints ();
3821 singlestep_breakpoints_inserted_p = 0;
3824 ecs->event_thread->control.trap_expected = 0;
3826 /* Note: We do not call context_switch at this point, as the
3827 context is already set up for stepping the original thread. */
3828 switch_to_thread (deferred_step_ptid);
3829 deferred_step_ptid = null_ptid;
3830 /* Suppress spurious "Switching to ..." message. */
3831 previous_inferior_ptid = inferior_ptid;
3833 resume (1, TARGET_SIGNAL_0);
3834 prepare_to_wait (ecs);
3838 deferred_step_ptid = null_ptid;
3841 /* See if a thread hit a thread-specific breakpoint that was meant for
3842 another thread. If so, then step that thread past the breakpoint,
3845 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP)
3847 int thread_hop_needed = 0;
3848 struct address_space *aspace =
3849 get_regcache_aspace (get_thread_regcache (ecs->ptid));
3851 /* Check if a regular breakpoint has been hit before checking
3852 for a potential single step breakpoint. Otherwise, GDB will
3853 not see this breakpoint hit when stepping onto breakpoints. */
3854 if (regular_breakpoint_inserted_here_p (aspace, stop_pc))
3856 ecs->random_signal = 0;
3857 if (!breakpoint_thread_match (aspace, stop_pc, ecs->ptid))
3858 thread_hop_needed = 1;
3860 else if (singlestep_breakpoints_inserted_p)
3862 /* We have not context switched yet, so this should be true
3863 no matter which thread hit the singlestep breakpoint. */
3864 gdb_assert (ptid_equal (inferior_ptid, singlestep_ptid));
3866 fprintf_unfiltered (gdb_stdlog, "infrun: software single step "
3868 target_pid_to_str (ecs->ptid));
3870 ecs->random_signal = 0;
3871 /* The call to in_thread_list is necessary because PTIDs sometimes
3872 change when we go from single-threaded to multi-threaded. If
3873 the singlestep_ptid is still in the list, assume that it is
3874 really different from ecs->ptid. */
3875 if (!ptid_equal (singlestep_ptid, ecs->ptid)
3876 && in_thread_list (singlestep_ptid))
3878 /* If the PC of the thread we were trying to single-step
3879 has changed, discard this event (which we were going
3880 to ignore anyway), and pretend we saw that thread
3881 trap. This prevents us continuously moving the
3882 single-step breakpoint forward, one instruction at a
3883 time. If the PC has changed, then the thread we were
3884 trying to single-step has trapped or been signalled,
3885 but the event has not been reported to GDB yet.
3887 There might be some cases where this loses signal
3888 information, if a signal has arrived at exactly the
3889 same time that the PC changed, but this is the best
3890 we can do with the information available. Perhaps we
3891 should arrange to report all events for all threads
3892 when they stop, or to re-poll the remote looking for
3893 this particular thread (i.e. temporarily enable
3896 CORE_ADDR new_singlestep_pc
3897 = regcache_read_pc (get_thread_regcache (singlestep_ptid));
3899 if (new_singlestep_pc != singlestep_pc)
3901 enum target_signal stop_signal;
3904 fprintf_unfiltered (gdb_stdlog, "infrun: unexpected thread,"
3905 " but expected thread advanced also\n");
3907 /* The current context still belongs to
3908 singlestep_ptid. Don't swap here, since that's
3909 the context we want to use. Just fudge our
3910 state and continue. */
3911 stop_signal = ecs->event_thread->suspend.stop_signal;
3912 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
3913 ecs->ptid = singlestep_ptid;
3914 ecs->event_thread = find_thread_ptid (ecs->ptid);
3915 ecs->event_thread->suspend.stop_signal = stop_signal;
3916 stop_pc = new_singlestep_pc;
3921 fprintf_unfiltered (gdb_stdlog,
3922 "infrun: unexpected thread\n");
3924 thread_hop_needed = 1;
3925 stepping_past_singlestep_breakpoint = 1;
3926 saved_singlestep_ptid = singlestep_ptid;
3931 if (thread_hop_needed)
3933 struct regcache *thread_regcache;
3934 int remove_status = 0;
3937 fprintf_unfiltered (gdb_stdlog, "infrun: thread_hop_needed\n");
3939 /* Switch context before touching inferior memory, the
3940 previous thread may have exited. */
3941 if (!ptid_equal (inferior_ptid, ecs->ptid))
3942 context_switch (ecs->ptid);
3944 /* Saw a breakpoint, but it was hit by the wrong thread.
3947 if (singlestep_breakpoints_inserted_p)
3949 /* Pull the single step breakpoints out of the target. */
3950 remove_single_step_breakpoints ();
3951 singlestep_breakpoints_inserted_p = 0;
3954 /* If the arch can displace step, don't remove the
3956 thread_regcache = get_thread_regcache (ecs->ptid);
3957 if (!use_displaced_stepping (get_regcache_arch (thread_regcache)))
3958 remove_status = remove_breakpoints ();
3960 /* Did we fail to remove breakpoints? If so, try
3961 to set the PC past the bp. (There's at least
3962 one situation in which we can fail to remove
3963 the bp's: On HP-UX's that use ttrace, we can't
3964 change the address space of a vforking child
3965 process until the child exits (well, okay, not
3966 then either :-) or execs. */
3967 if (remove_status != 0)
3968 error (_("Cannot step over breakpoint hit in wrong thread"));
3973 /* Only need to require the next event from this
3974 thread in all-stop mode. */
3975 waiton_ptid = ecs->ptid;
3976 infwait_state = infwait_thread_hop_state;
3979 ecs->event_thread->stepping_over_breakpoint = 1;
3984 else if (singlestep_breakpoints_inserted_p)
3986 ecs->random_signal = 0;
3990 ecs->random_signal = 1;
3992 /* See if something interesting happened to the non-current thread. If
3993 so, then switch to that thread. */
3994 if (!ptid_equal (ecs->ptid, inferior_ptid))
3997 fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n");
3999 context_switch (ecs->ptid);
4001 if (deprecated_context_hook)
4002 deprecated_context_hook (pid_to_thread_id (ecs->ptid));
4005 /* At this point, get hold of the now-current thread's frame. */
4006 frame = get_current_frame ();
4007 gdbarch = get_frame_arch (frame);
4009 if (singlestep_breakpoints_inserted_p)
4011 /* Pull the single step breakpoints out of the target. */
4012 remove_single_step_breakpoints ();
4013 singlestep_breakpoints_inserted_p = 0;
4016 if (stepped_after_stopped_by_watchpoint)
4017 stopped_by_watchpoint = 0;
4019 stopped_by_watchpoint = watchpoints_triggered (&ecs->ws);
4021 /* If necessary, step over this watchpoint. We'll be back to display
4023 if (stopped_by_watchpoint
4024 && (target_have_steppable_watchpoint
4025 || gdbarch_have_nonsteppable_watchpoint (gdbarch)))
4027 /* At this point, we are stopped at an instruction which has
4028 attempted to write to a piece of memory under control of
4029 a watchpoint. The instruction hasn't actually executed
4030 yet. If we were to evaluate the watchpoint expression
4031 now, we would get the old value, and therefore no change
4032 would seem to have occurred.
4034 In order to make watchpoints work `right', we really need
4035 to complete the memory write, and then evaluate the
4036 watchpoint expression. We do this by single-stepping the
4039 It may not be necessary to disable the watchpoint to stop over
4040 it. For example, the PA can (with some kernel cooperation)
4041 single step over a watchpoint without disabling the watchpoint.
4043 It is far more common to need to disable a watchpoint to step
4044 the inferior over it. If we have non-steppable watchpoints,
4045 we must disable the current watchpoint; it's simplest to
4046 disable all watchpoints and breakpoints. */
4049 if (!target_have_steppable_watchpoint)
4051 remove_breakpoints ();
4052 /* See comment in resume why we need to stop bypassing signals
4053 while breakpoints have been removed. */
4054 target_pass_signals (0, NULL);
4057 hw_step = maybe_software_singlestep (gdbarch, stop_pc);
4058 target_resume (ecs->ptid, hw_step, TARGET_SIGNAL_0);
4059 waiton_ptid = ecs->ptid;
4060 if (target_have_steppable_watchpoint)
4061 infwait_state = infwait_step_watch_state;
4063 infwait_state = infwait_nonstep_watch_state;
4064 prepare_to_wait (ecs);
4068 clear_stop_func (ecs);
4069 ecs->event_thread->stepping_over_breakpoint = 0;
4070 bpstat_clear (&ecs->event_thread->control.stop_bpstat);
4071 ecs->event_thread->control.stop_step = 0;
4072 stop_print_frame = 1;
4073 ecs->random_signal = 0;
4074 stopped_by_random_signal = 0;
4076 /* Hide inlined functions starting here, unless we just performed stepi or
4077 nexti. After stepi and nexti, always show the innermost frame (not any
4078 inline function call sites). */
4079 if (ecs->event_thread->control.step_range_end != 1)
4081 struct address_space *aspace =
4082 get_regcache_aspace (get_thread_regcache (ecs->ptid));
4084 /* skip_inline_frames is expensive, so we avoid it if we can
4085 determine that the address is one where functions cannot have
4086 been inlined. This improves performance with inferiors that
4087 load a lot of shared libraries, because the solib event
4088 breakpoint is defined as the address of a function (i.e. not
4089 inline). Note that we have to check the previous PC as well
4090 as the current one to catch cases when we have just
4091 single-stepped off a breakpoint prior to reinstating it.
4092 Note that we're assuming that the code we single-step to is
4093 not inline, but that's not definitive: there's nothing
4094 preventing the event breakpoint function from containing
4095 inlined code, and the single-step ending up there. If the
4096 user had set a breakpoint on that inlined code, the missing
4097 skip_inline_frames call would break things. Fortunately
4098 that's an extremely unlikely scenario. */
4099 if (!pc_at_non_inline_function (aspace, stop_pc)
4100 && !(ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP
4101 && ecs->event_thread->control.trap_expected
4102 && pc_at_non_inline_function (aspace,
4103 ecs->event_thread->prev_pc)))
4104 skip_inline_frames (ecs->ptid);
4107 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP
4108 && ecs->event_thread->control.trap_expected
4109 && gdbarch_single_step_through_delay_p (gdbarch)
4110 && currently_stepping (ecs->event_thread))
4112 /* We're trying to step off a breakpoint. Turns out that we're
4113 also on an instruction that needs to be stepped multiple
4114 times before it's been fully executing. E.g., architectures
4115 with a delay slot. It needs to be stepped twice, once for
4116 the instruction and once for the delay slot. */
4117 int step_through_delay
4118 = gdbarch_single_step_through_delay (gdbarch, frame);
4120 if (debug_infrun && step_through_delay)
4121 fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n");
4122 if (ecs->event_thread->control.step_range_end == 0
4123 && step_through_delay)
4125 /* The user issued a continue when stopped at a breakpoint.
4126 Set up for another trap and get out of here. */
4127 ecs->event_thread->stepping_over_breakpoint = 1;
4131 else if (step_through_delay)
4133 /* The user issued a step when stopped at a breakpoint.
4134 Maybe we should stop, maybe we should not - the delay
4135 slot *might* correspond to a line of source. In any
4136 case, don't decide that here, just set
4137 ecs->stepping_over_breakpoint, making sure we
4138 single-step again before breakpoints are re-inserted. */
4139 ecs->event_thread->stepping_over_breakpoint = 1;
4143 /* Look at the cause of the stop, and decide what to do.
4144 The alternatives are:
4145 1) stop_stepping and return; to really stop and return to the debugger,
4146 2) keep_going and return to start up again
4147 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
4148 3) set ecs->random_signal to 1, and the decision between 1 and 2
4149 will be made according to the signal handling tables. */
4151 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP
4152 || stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_NO_SIGSTOP
4153 || stop_soon == STOP_QUIETLY_REMOTE)
4155 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP
4159 fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n");
4160 stop_print_frame = 0;
4161 stop_stepping (ecs);
4165 /* This is originated from start_remote(), start_inferior() and
4166 shared libraries hook functions. */
4167 if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE)
4170 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
4171 stop_stepping (ecs);
4175 /* This originates from attach_command(). We need to overwrite
4176 the stop_signal here, because some kernels don't ignore a
4177 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4178 See more comments in inferior.h. On the other hand, if we
4179 get a non-SIGSTOP, report it to the user - assume the backend
4180 will handle the SIGSTOP if it should show up later.
4182 Also consider that the attach is complete when we see a
4183 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4184 target extended-remote report it instead of a SIGSTOP
4185 (e.g. gdbserver). We already rely on SIGTRAP being our
4186 signal, so this is no exception.
4188 Also consider that the attach is complete when we see a
4189 TARGET_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4190 the target to stop all threads of the inferior, in case the
4191 low level attach operation doesn't stop them implicitly. If
4192 they weren't stopped implicitly, then the stub will report a
4193 TARGET_SIGNAL_0, meaning: stopped for no particular reason
4194 other than GDB's request. */
4195 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
4196 && (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_STOP
4197 || ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP
4198 || ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_0))
4200 stop_stepping (ecs);
4201 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
4205 /* See if there is a breakpoint at the current PC. */
4206 ecs->event_thread->control.stop_bpstat
4207 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4208 stop_pc, ecs->ptid);
4210 /* Following in case break condition called a
4212 stop_print_frame = 1;
4214 /* This is where we handle "moribund" watchpoints. Unlike
4215 software breakpoints traps, hardware watchpoint traps are
4216 always distinguishable from random traps. If no high-level
4217 watchpoint is associated with the reported stop data address
4218 anymore, then the bpstat does not explain the signal ---
4219 simply make sure to ignore it if `stopped_by_watchpoint' is
4223 && ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP
4224 && !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat)
4225 && stopped_by_watchpoint)
4226 fprintf_unfiltered (gdb_stdlog,
4227 "infrun: no user watchpoint explains "
4228 "watchpoint SIGTRAP, ignoring\n");
4230 /* NOTE: cagney/2003-03-29: These two checks for a random signal
4231 at one stage in the past included checks for an inferior
4232 function call's call dummy's return breakpoint. The original
4233 comment, that went with the test, read:
4235 ``End of a stack dummy. Some systems (e.g. Sony news) give
4236 another signal besides SIGTRAP, so check here as well as
4239 If someone ever tries to get call dummys on a
4240 non-executable stack to work (where the target would stop
4241 with something like a SIGSEGV), then those tests might need
4242 to be re-instated. Given, however, that the tests were only
4243 enabled when momentary breakpoints were not being used, I
4244 suspect that it won't be the case.
4246 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4247 be necessary for call dummies on a non-executable stack on
4250 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP)
4252 = !(bpstat_explains_signal (ecs->event_thread->control.stop_bpstat)
4253 || stopped_by_watchpoint
4254 || ecs->event_thread->control.trap_expected
4255 || (ecs->event_thread->control.step_range_end
4256 && (ecs->event_thread->control.step_resume_breakpoint
4260 ecs->random_signal = !bpstat_explains_signal
4261 (ecs->event_thread->control.stop_bpstat);
4262 if (!ecs->random_signal)
4263 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_TRAP;
4267 /* When we reach this point, we've pretty much decided
4268 that the reason for stopping must've been a random
4269 (unexpected) signal. */
4272 ecs->random_signal = 1;
4274 process_event_stop_test:
4276 /* Re-fetch current thread's frame in case we did a
4277 "goto process_event_stop_test" above. */
4278 frame = get_current_frame ();
4279 gdbarch = get_frame_arch (frame);
4281 /* For the program's own signals, act according to
4282 the signal handling tables. */
4284 if (ecs->random_signal)
4286 /* Signal not for debugging purposes. */
4288 struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
4291 fprintf_unfiltered (gdb_stdlog, "infrun: random signal %d\n",
4292 ecs->event_thread->suspend.stop_signal);
4294 stopped_by_random_signal = 1;
4296 if (signal_print[ecs->event_thread->suspend.stop_signal])
4299 target_terminal_ours_for_output ();
4300 print_signal_received_reason
4301 (ecs->event_thread->suspend.stop_signal);
4303 /* Always stop on signals if we're either just gaining control
4304 of the program, or the user explicitly requested this thread
4305 to remain stopped. */
4306 if (stop_soon != NO_STOP_QUIETLY
4307 || ecs->event_thread->stop_requested
4309 && signal_stop_state (ecs->event_thread->suspend.stop_signal)))
4311 stop_stepping (ecs);
4314 /* If not going to stop, give terminal back
4315 if we took it away. */
4317 target_terminal_inferior ();
4319 /* Clear the signal if it should not be passed. */
4320 if (signal_program[ecs->event_thread->suspend.stop_signal] == 0)
4321 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
4323 if (ecs->event_thread->prev_pc == stop_pc
4324 && ecs->event_thread->control.trap_expected
4325 && ecs->event_thread->control.step_resume_breakpoint == NULL)
4327 /* We were just starting a new sequence, attempting to
4328 single-step off of a breakpoint and expecting a SIGTRAP.
4329 Instead this signal arrives. This signal will take us out
4330 of the stepping range so GDB needs to remember to, when
4331 the signal handler returns, resume stepping off that
4333 /* To simplify things, "continue" is forced to use the same
4334 code paths as single-step - set a breakpoint at the
4335 signal return address and then, once hit, step off that
4338 fprintf_unfiltered (gdb_stdlog,
4339 "infrun: signal arrived while stepping over "
4342 insert_hp_step_resume_breakpoint_at_frame (frame);
4343 ecs->event_thread->step_after_step_resume_breakpoint = 1;
4344 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4345 ecs->event_thread->control.trap_expected = 0;
4350 if (ecs->event_thread->control.step_range_end != 0
4351 && ecs->event_thread->suspend.stop_signal != TARGET_SIGNAL_0
4352 && (ecs->event_thread->control.step_range_start <= stop_pc
4353 && stop_pc < ecs->event_thread->control.step_range_end)
4354 && frame_id_eq (get_stack_frame_id (frame),
4355 ecs->event_thread->control.step_stack_frame_id)
4356 && ecs->event_thread->control.step_resume_breakpoint == NULL)
4358 /* The inferior is about to take a signal that will take it
4359 out of the single step range. Set a breakpoint at the
4360 current PC (which is presumably where the signal handler
4361 will eventually return) and then allow the inferior to
4364 Note that this is only needed for a signal delivered
4365 while in the single-step range. Nested signals aren't a
4366 problem as they eventually all return. */
4368 fprintf_unfiltered (gdb_stdlog,
4369 "infrun: signal may take us out of "
4370 "single-step range\n");
4372 insert_hp_step_resume_breakpoint_at_frame (frame);
4373 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4374 ecs->event_thread->control.trap_expected = 0;
4379 /* Note: step_resume_breakpoint may be non-NULL. This occures
4380 when either there's a nested signal, or when there's a
4381 pending signal enabled just as the signal handler returns
4382 (leaving the inferior at the step-resume-breakpoint without
4383 actually executing it). Either way continue until the
4384 breakpoint is really hit. */
4389 /* Handle cases caused by hitting a breakpoint. */
4391 CORE_ADDR jmp_buf_pc;
4392 struct bpstat_what what;
4394 what = bpstat_what (ecs->event_thread->control.stop_bpstat);
4396 if (what.call_dummy)
4398 stop_stack_dummy = what.call_dummy;
4401 /* If we hit an internal event that triggers symbol changes, the
4402 current frame will be invalidated within bpstat_what (e.g., if
4403 we hit an internal solib event). Re-fetch it. */
4404 frame = get_current_frame ();
4405 gdbarch = get_frame_arch (frame);
4407 switch (what.main_action)
4409 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
4410 /* If we hit the breakpoint at longjmp while stepping, we
4411 install a momentary breakpoint at the target of the
4415 fprintf_unfiltered (gdb_stdlog,
4416 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4418 ecs->event_thread->stepping_over_breakpoint = 1;
4420 if (what.is_longjmp)
4422 if (!gdbarch_get_longjmp_target_p (gdbarch)
4423 || !gdbarch_get_longjmp_target (gdbarch,
4424 frame, &jmp_buf_pc))
4427 fprintf_unfiltered (gdb_stdlog,
4428 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4429 "(!gdbarch_get_longjmp_target)\n");
4434 /* We're going to replace the current step-resume breakpoint
4435 with a longjmp-resume breakpoint. */
4436 delete_step_resume_breakpoint (ecs->event_thread);
4438 /* Insert a breakpoint at resume address. */
4439 insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc);
4443 struct symbol *func = get_frame_function (frame);
4446 check_exception_resume (ecs, frame, func);
4451 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
4453 fprintf_unfiltered (gdb_stdlog,
4454 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4456 if (what.is_longjmp)
4458 gdb_assert (ecs->event_thread->control.step_resume_breakpoint
4460 delete_step_resume_breakpoint (ecs->event_thread);
4464 /* There are several cases to consider.
4466 1. The initiating frame no longer exists. In this case
4467 we must stop, because the exception has gone too far.
4469 2. The initiating frame exists, and is the same as the
4470 current frame. We stop, because the exception has been
4473 3. The initiating frame exists and is different from
4474 the current frame. This means the exception has been
4475 caught beneath the initiating frame, so keep going. */
4476 struct frame_info *init_frame
4477 = frame_find_by_id (ecs->event_thread->initiating_frame);
4479 gdb_assert (ecs->event_thread->control.exception_resume_breakpoint
4481 delete_exception_resume_breakpoint (ecs->event_thread);
4485 struct frame_id current_id
4486 = get_frame_id (get_current_frame ());
4487 if (frame_id_eq (current_id,
4488 ecs->event_thread->initiating_frame))
4490 /* Case 2. Fall through. */
4500 /* For Cases 1 and 2, remove the step-resume breakpoint,
4502 delete_step_resume_breakpoint (ecs->event_thread);
4505 ecs->event_thread->control.stop_step = 1;
4506 print_end_stepping_range_reason ();
4507 stop_stepping (ecs);
4510 case BPSTAT_WHAT_SINGLE:
4512 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
4513 ecs->event_thread->stepping_over_breakpoint = 1;
4514 /* Still need to check other stuff, at least the case
4515 where we are stepping and step out of the right range. */
4518 case BPSTAT_WHAT_STEP_RESUME:
4520 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4522 delete_step_resume_breakpoint (ecs->event_thread);
4523 if (ecs->event_thread->control.proceed_to_finish
4524 && execution_direction == EXEC_REVERSE)
4526 struct thread_info *tp = ecs->event_thread;
4528 /* We are finishing a function in reverse, and just hit
4529 the step-resume breakpoint at the start address of the
4530 function, and we're almost there -- just need to back
4531 up by one more single-step, which should take us back
4532 to the function call. */
4533 tp->control.step_range_start = tp->control.step_range_end = 1;
4537 fill_in_stop_func (gdbarch, ecs);
4538 if (stop_pc == ecs->stop_func_start
4539 && execution_direction == EXEC_REVERSE)
4541 /* We are stepping over a function call in reverse, and
4542 just hit the step-resume breakpoint at the start
4543 address of the function. Go back to single-stepping,
4544 which should take us back to the function call. */
4545 ecs->event_thread->stepping_over_breakpoint = 1;
4551 case BPSTAT_WHAT_STOP_NOISY:
4553 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4554 stop_print_frame = 1;
4556 /* We are about to nuke the step_resume_breakpointt via the
4557 cleanup chain, so no need to worry about it here. */
4559 stop_stepping (ecs);
4562 case BPSTAT_WHAT_STOP_SILENT:
4564 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4565 stop_print_frame = 0;
4567 /* We are about to nuke the step_resume_breakpoin via the
4568 cleanup chain, so no need to worry about it here. */
4570 stop_stepping (ecs);
4573 case BPSTAT_WHAT_HP_STEP_RESUME:
4575 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4577 delete_step_resume_breakpoint (ecs->event_thread);
4578 if (ecs->event_thread->step_after_step_resume_breakpoint)
4580 /* Back when the step-resume breakpoint was inserted, we
4581 were trying to single-step off a breakpoint. Go back
4583 ecs->event_thread->step_after_step_resume_breakpoint = 0;
4584 ecs->event_thread->stepping_over_breakpoint = 1;
4590 case BPSTAT_WHAT_KEEP_CHECKING:
4595 /* We come here if we hit a breakpoint but should not
4596 stop for it. Possibly we also were stepping
4597 and should stop for that. So fall through and
4598 test for stepping. But, if not stepping,
4601 /* In all-stop mode, if we're currently stepping but have stopped in
4602 some other thread, we need to switch back to the stepped thread. */
4605 struct thread_info *tp;
4607 tp = iterate_over_threads (currently_stepping_or_nexting_callback,
4611 /* However, if the current thread is blocked on some internal
4612 breakpoint, and we simply need to step over that breakpoint
4613 to get it going again, do that first. */
4614 if ((ecs->event_thread->control.trap_expected
4615 && ecs->event_thread->suspend.stop_signal != TARGET_SIGNAL_TRAP)
4616 || ecs->event_thread->stepping_over_breakpoint)
4622 /* If the stepping thread exited, then don't try to switch
4623 back and resume it, which could fail in several different
4624 ways depending on the target. Instead, just keep going.
4626 We can find a stepping dead thread in the thread list in
4629 - The target supports thread exit events, and when the
4630 target tries to delete the thread from the thread list,
4631 inferior_ptid pointed at the exiting thread. In such
4632 case, calling delete_thread does not really remove the
4633 thread from the list; instead, the thread is left listed,
4634 with 'exited' state.
4636 - The target's debug interface does not support thread
4637 exit events, and so we have no idea whatsoever if the
4638 previously stepping thread is still alive. For that
4639 reason, we need to synchronously query the target
4641 if (is_exited (tp->ptid)
4642 || !target_thread_alive (tp->ptid))
4645 fprintf_unfiltered (gdb_stdlog,
4646 "infrun: not switching back to "
4647 "stepped thread, it has vanished\n");
4649 delete_thread (tp->ptid);
4654 /* Otherwise, we no longer expect a trap in the current thread.
4655 Clear the trap_expected flag before switching back -- this is
4656 what keep_going would do as well, if we called it. */
4657 ecs->event_thread->control.trap_expected = 0;
4660 fprintf_unfiltered (gdb_stdlog,
4661 "infrun: switching back to stepped thread\n");
4663 ecs->event_thread = tp;
4664 ecs->ptid = tp->ptid;
4665 context_switch (ecs->ptid);
4671 if (ecs->event_thread->control.step_resume_breakpoint)
4674 fprintf_unfiltered (gdb_stdlog,
4675 "infrun: step-resume breakpoint is inserted\n");
4677 /* Having a step-resume breakpoint overrides anything
4678 else having to do with stepping commands until
4679 that breakpoint is reached. */
4684 if (ecs->event_thread->control.step_range_end == 0)
4687 fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n");
4688 /* Likewise if we aren't even stepping. */
4693 /* Re-fetch current thread's frame in case the code above caused
4694 the frame cache to be re-initialized, making our FRAME variable
4695 a dangling pointer. */
4696 frame = get_current_frame ();
4697 gdbarch = get_frame_arch (frame);
4698 fill_in_stop_func (gdbarch, ecs);
4700 /* If stepping through a line, keep going if still within it.
4702 Note that step_range_end is the address of the first instruction
4703 beyond the step range, and NOT the address of the last instruction
4706 Note also that during reverse execution, we may be stepping
4707 through a function epilogue and therefore must detect when
4708 the current-frame changes in the middle of a line. */
4710 if (stop_pc >= ecs->event_thread->control.step_range_start
4711 && stop_pc < ecs->event_thread->control.step_range_end
4712 && (execution_direction != EXEC_REVERSE
4713 || frame_id_eq (get_frame_id (frame),
4714 ecs->event_thread->control.step_frame_id)))
4718 (gdb_stdlog, "infrun: stepping inside range [%s-%s]\n",
4719 paddress (gdbarch, ecs->event_thread->control.step_range_start),
4720 paddress (gdbarch, ecs->event_thread->control.step_range_end));
4722 /* When stepping backward, stop at beginning of line range
4723 (unless it's the function entry point, in which case
4724 keep going back to the call point). */
4725 if (stop_pc == ecs->event_thread->control.step_range_start
4726 && stop_pc != ecs->stop_func_start
4727 && execution_direction == EXEC_REVERSE)
4729 ecs->event_thread->control.stop_step = 1;
4730 print_end_stepping_range_reason ();
4731 stop_stepping (ecs);
4739 /* We stepped out of the stepping range. */
4741 /* If we are stepping at the source level and entered the runtime
4742 loader dynamic symbol resolution code...
4744 EXEC_FORWARD: we keep on single stepping until we exit the run
4745 time loader code and reach the callee's address.
4747 EXEC_REVERSE: we've already executed the callee (backward), and
4748 the runtime loader code is handled just like any other
4749 undebuggable function call. Now we need only keep stepping
4750 backward through the trampoline code, and that's handled further
4751 down, so there is nothing for us to do here. */
4753 if (execution_direction != EXEC_REVERSE
4754 && ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
4755 && in_solib_dynsym_resolve_code (stop_pc))
4757 CORE_ADDR pc_after_resolver =
4758 gdbarch_skip_solib_resolver (gdbarch, stop_pc);
4761 fprintf_unfiltered (gdb_stdlog,
4762 "infrun: stepped into dynsym resolve code\n");
4764 if (pc_after_resolver)
4766 /* Set up a step-resume breakpoint at the address
4767 indicated by SKIP_SOLIB_RESOLVER. */
4768 struct symtab_and_line sr_sal;
4771 sr_sal.pc = pc_after_resolver;
4772 sr_sal.pspace = get_frame_program_space (frame);
4774 insert_step_resume_breakpoint_at_sal (gdbarch,
4775 sr_sal, null_frame_id);
4782 if (ecs->event_thread->control.step_range_end != 1
4783 && (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
4784 || ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
4785 && get_frame_type (frame) == SIGTRAMP_FRAME)
4788 fprintf_unfiltered (gdb_stdlog,
4789 "infrun: stepped into signal trampoline\n");
4790 /* The inferior, while doing a "step" or "next", has ended up in
4791 a signal trampoline (either by a signal being delivered or by
4792 the signal handler returning). Just single-step until the
4793 inferior leaves the trampoline (either by calling the handler
4799 /* Check for subroutine calls. The check for the current frame
4800 equalling the step ID is not necessary - the check of the
4801 previous frame's ID is sufficient - but it is a common case and
4802 cheaper than checking the previous frame's ID.
4804 NOTE: frame_id_eq will never report two invalid frame IDs as
4805 being equal, so to get into this block, both the current and
4806 previous frame must have valid frame IDs. */
4807 /* The outer_frame_id check is a heuristic to detect stepping
4808 through startup code. If we step over an instruction which
4809 sets the stack pointer from an invalid value to a valid value,
4810 we may detect that as a subroutine call from the mythical
4811 "outermost" function. This could be fixed by marking
4812 outermost frames as !stack_p,code_p,special_p. Then the
4813 initial outermost frame, before sp was valid, would
4814 have code_addr == &_start. See the comment in frame_id_eq
4816 if (!frame_id_eq (get_stack_frame_id (frame),
4817 ecs->event_thread->control.step_stack_frame_id)
4818 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4819 ecs->event_thread->control.step_stack_frame_id)
4820 && (!frame_id_eq (ecs->event_thread->control.step_stack_frame_id,
4822 || step_start_function != find_pc_function (stop_pc))))
4824 CORE_ADDR real_stop_pc;
4827 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n");
4829 if ((ecs->event_thread->control.step_over_calls == STEP_OVER_NONE)
4830 || ((ecs->event_thread->control.step_range_end == 1)
4831 && in_prologue (gdbarch, ecs->event_thread->prev_pc,
4832 ecs->stop_func_start)))
4834 /* I presume that step_over_calls is only 0 when we're
4835 supposed to be stepping at the assembly language level
4836 ("stepi"). Just stop. */
4837 /* Also, maybe we just did a "nexti" inside a prolog, so we
4838 thought it was a subroutine call but it was not. Stop as
4840 /* And this works the same backward as frontward. MVS */
4841 ecs->event_thread->control.stop_step = 1;
4842 print_end_stepping_range_reason ();
4843 stop_stepping (ecs);
4847 /* Reverse stepping through solib trampolines. */
4849 if (execution_direction == EXEC_REVERSE
4850 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE
4851 && (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
4852 || (ecs->stop_func_start == 0
4853 && in_solib_dynsym_resolve_code (stop_pc))))
4855 /* Any solib trampoline code can be handled in reverse
4856 by simply continuing to single-step. We have already
4857 executed the solib function (backwards), and a few
4858 steps will take us back through the trampoline to the
4864 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
4866 /* We're doing a "next".
4868 Normal (forward) execution: set a breakpoint at the
4869 callee's return address (the address at which the caller
4872 Reverse (backward) execution. set the step-resume
4873 breakpoint at the start of the function that we just
4874 stepped into (backwards), and continue to there. When we
4875 get there, we'll need to single-step back to the caller. */
4877 if (execution_direction == EXEC_REVERSE)
4879 struct symtab_and_line sr_sal;
4881 /* Normal function call return (static or dynamic). */
4883 sr_sal.pc = ecs->stop_func_start;
4884 sr_sal.pspace = get_frame_program_space (frame);
4885 insert_step_resume_breakpoint_at_sal (gdbarch,
4886 sr_sal, null_frame_id);
4889 insert_step_resume_breakpoint_at_caller (frame);
4895 /* If we are in a function call trampoline (a stub between the
4896 calling routine and the real function), locate the real
4897 function. That's what tells us (a) whether we want to step
4898 into it at all, and (b) what prologue we want to run to the
4899 end of, if we do step into it. */
4900 real_stop_pc = skip_language_trampoline (frame, stop_pc);
4901 if (real_stop_pc == 0)
4902 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
4903 if (real_stop_pc != 0)
4904 ecs->stop_func_start = real_stop_pc;
4906 if (real_stop_pc != 0 && in_solib_dynsym_resolve_code (real_stop_pc))
4908 struct symtab_and_line sr_sal;
4911 sr_sal.pc = ecs->stop_func_start;
4912 sr_sal.pspace = get_frame_program_space (frame);
4914 insert_step_resume_breakpoint_at_sal (gdbarch,
4915 sr_sal, null_frame_id);
4920 /* If we have line number information for the function we are
4921 thinking of stepping into and the function isn't on the skip
4924 If there are several symtabs at that PC (e.g. with include
4925 files), just want to know whether *any* of them have line
4926 numbers. find_pc_line handles this. */
4928 struct symtab_and_line tmp_sal;
4930 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
4931 if (tmp_sal.line != 0 &&
4932 !function_pc_is_marked_for_skip (ecs->stop_func_start))
4934 if (execution_direction == EXEC_REVERSE)
4935 handle_step_into_function_backward (gdbarch, ecs);
4937 handle_step_into_function (gdbarch, ecs);
4942 /* If we have no line number and the step-stop-if-no-debug is
4943 set, we stop the step so that the user has a chance to switch
4944 in assembly mode. */
4945 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
4946 && step_stop_if_no_debug)
4948 ecs->event_thread->control.stop_step = 1;
4949 print_end_stepping_range_reason ();
4950 stop_stepping (ecs);
4954 if (execution_direction == EXEC_REVERSE)
4956 /* Set a breakpoint at callee's start address.
4957 From there we can step once and be back in the caller. */
4958 struct symtab_and_line sr_sal;
4961 sr_sal.pc = ecs->stop_func_start;
4962 sr_sal.pspace = get_frame_program_space (frame);
4963 insert_step_resume_breakpoint_at_sal (gdbarch,
4964 sr_sal, null_frame_id);
4967 /* Set a breakpoint at callee's return address (the address
4968 at which the caller will resume). */
4969 insert_step_resume_breakpoint_at_caller (frame);
4975 /* Reverse stepping through solib trampolines. */
4977 if (execution_direction == EXEC_REVERSE
4978 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
4980 if (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
4981 || (ecs->stop_func_start == 0
4982 && in_solib_dynsym_resolve_code (stop_pc)))
4984 /* Any solib trampoline code can be handled in reverse
4985 by simply continuing to single-step. We have already
4986 executed the solib function (backwards), and a few
4987 steps will take us back through the trampoline to the
4992 else if (in_solib_dynsym_resolve_code (stop_pc))
4994 /* Stepped backward into the solib dynsym resolver.
4995 Set a breakpoint at its start and continue, then
4996 one more step will take us out. */
4997 struct symtab_and_line sr_sal;
5000 sr_sal.pc = ecs->stop_func_start;
5001 sr_sal.pspace = get_frame_program_space (frame);
5002 insert_step_resume_breakpoint_at_sal (gdbarch,
5003 sr_sal, null_frame_id);
5009 /* If we're in the return path from a shared library trampoline,
5010 we want to proceed through the trampoline when stepping. */
5011 if (gdbarch_in_solib_return_trampoline (gdbarch,
5012 stop_pc, ecs->stop_func_name))
5014 /* Determine where this trampoline returns. */
5015 CORE_ADDR real_stop_pc;
5017 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
5020 fprintf_unfiltered (gdb_stdlog,
5021 "infrun: stepped into solib return tramp\n");
5023 /* Only proceed through if we know where it's going. */
5026 /* And put the step-breakpoint there and go until there. */
5027 struct symtab_and_line sr_sal;
5029 init_sal (&sr_sal); /* initialize to zeroes */
5030 sr_sal.pc = real_stop_pc;
5031 sr_sal.section = find_pc_overlay (sr_sal.pc);
5032 sr_sal.pspace = get_frame_program_space (frame);
5034 /* Do not specify what the fp should be when we stop since
5035 on some machines the prologue is where the new fp value
5037 insert_step_resume_breakpoint_at_sal (gdbarch,
5038 sr_sal, null_frame_id);
5040 /* Restart without fiddling with the step ranges or
5047 stop_pc_sal = find_pc_line (stop_pc, 0);
5049 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5050 the trampoline processing logic, however, there are some trampolines
5051 that have no names, so we should do trampoline handling first. */
5052 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
5053 && ecs->stop_func_name == NULL
5054 && stop_pc_sal.line == 0)
5057 fprintf_unfiltered (gdb_stdlog,
5058 "infrun: stepped into undebuggable function\n");
5060 /* The inferior just stepped into, or returned to, an
5061 undebuggable function (where there is no debugging information
5062 and no line number corresponding to the address where the
5063 inferior stopped). Since we want to skip this kind of code,
5064 we keep going until the inferior returns from this
5065 function - unless the user has asked us not to (via
5066 set step-mode) or we no longer know how to get back
5067 to the call site. */
5068 if (step_stop_if_no_debug
5069 || !frame_id_p (frame_unwind_caller_id (frame)))
5071 /* If we have no line number and the step-stop-if-no-debug
5072 is set, we stop the step so that the user has a chance to
5073 switch in assembly mode. */
5074 ecs->event_thread->control.stop_step = 1;
5075 print_end_stepping_range_reason ();
5076 stop_stepping (ecs);
5081 /* Set a breakpoint at callee's return address (the address
5082 at which the caller will resume). */
5083 insert_step_resume_breakpoint_at_caller (frame);
5089 if (ecs->event_thread->control.step_range_end == 1)
5091 /* It is stepi or nexti. We always want to stop stepping after
5094 fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
5095 ecs->event_thread->control.stop_step = 1;
5096 print_end_stepping_range_reason ();
5097 stop_stepping (ecs);
5101 if (stop_pc_sal.line == 0)
5103 /* We have no line number information. That means to stop
5104 stepping (does this always happen right after one instruction,
5105 when we do "s" in a function with no line numbers,
5106 or can this happen as a result of a return or longjmp?). */
5108 fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n");
5109 ecs->event_thread->control.stop_step = 1;
5110 print_end_stepping_range_reason ();
5111 stop_stepping (ecs);
5115 /* Look for "calls" to inlined functions, part one. If the inline
5116 frame machinery detected some skipped call sites, we have entered
5117 a new inline function. */
5119 if (frame_id_eq (get_frame_id (get_current_frame ()),
5120 ecs->event_thread->control.step_frame_id)
5121 && inline_skipped_frames (ecs->ptid))
5123 struct symtab_and_line call_sal;
5126 fprintf_unfiltered (gdb_stdlog,
5127 "infrun: stepped into inlined function\n");
5129 find_frame_sal (get_current_frame (), &call_sal);
5131 if (ecs->event_thread->control.step_over_calls != STEP_OVER_ALL)
5133 /* For "step", we're going to stop. But if the call site
5134 for this inlined function is on the same source line as
5135 we were previously stepping, go down into the function
5136 first. Otherwise stop at the call site. */
5138 if (call_sal.line == ecs->event_thread->current_line
5139 && call_sal.symtab == ecs->event_thread->current_symtab)
5140 step_into_inline_frame (ecs->ptid);
5142 ecs->event_thread->control.stop_step = 1;
5143 print_end_stepping_range_reason ();
5144 stop_stepping (ecs);
5149 /* For "next", we should stop at the call site if it is on a
5150 different source line. Otherwise continue through the
5151 inlined function. */
5152 if (call_sal.line == ecs->event_thread->current_line
5153 && call_sal.symtab == ecs->event_thread->current_symtab)
5157 ecs->event_thread->control.stop_step = 1;
5158 print_end_stepping_range_reason ();
5159 stop_stepping (ecs);
5165 /* Look for "calls" to inlined functions, part two. If we are still
5166 in the same real function we were stepping through, but we have
5167 to go further up to find the exact frame ID, we are stepping
5168 through a more inlined call beyond its call site. */
5170 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5171 && !frame_id_eq (get_frame_id (get_current_frame ()),
5172 ecs->event_thread->control.step_frame_id)
5173 && stepped_in_from (get_current_frame (),
5174 ecs->event_thread->control.step_frame_id))
5177 fprintf_unfiltered (gdb_stdlog,
5178 "infrun: stepping through inlined function\n");
5180 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
5184 ecs->event_thread->control.stop_step = 1;
5185 print_end_stepping_range_reason ();
5186 stop_stepping (ecs);
5191 if ((stop_pc == stop_pc_sal.pc)
5192 && (ecs->event_thread->current_line != stop_pc_sal.line
5193 || ecs->event_thread->current_symtab != stop_pc_sal.symtab))
5195 /* We are at the start of a different line. So stop. Note that
5196 we don't stop if we step into the middle of a different line.
5197 That is said to make things like for (;;) statements work
5200 fprintf_unfiltered (gdb_stdlog,
5201 "infrun: stepped to a different line\n");
5202 ecs->event_thread->control.stop_step = 1;
5203 print_end_stepping_range_reason ();
5204 stop_stepping (ecs);
5208 /* We aren't done stepping.
5210 Optimize by setting the stepping range to the line.
5211 (We might not be in the original line, but if we entered a
5212 new line in mid-statement, we continue stepping. This makes
5213 things like for(;;) statements work better.) */
5215 ecs->event_thread->control.step_range_start = stop_pc_sal.pc;
5216 ecs->event_thread->control.step_range_end = stop_pc_sal.end;
5217 set_step_info (frame, stop_pc_sal);
5220 fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n");
5224 /* Is thread TP in the middle of single-stepping? */
5227 currently_stepping (struct thread_info *tp)
5229 return ((tp->control.step_range_end
5230 && tp->control.step_resume_breakpoint == NULL)
5231 || tp->control.trap_expected
5232 || bpstat_should_step ());
5235 /* Returns true if any thread *but* the one passed in "data" is in the
5236 middle of stepping or of handling a "next". */
5239 currently_stepping_or_nexting_callback (struct thread_info *tp, void *data)
5244 return (tp->control.step_range_end
5245 || tp->control.trap_expected);
5248 /* Inferior has stepped into a subroutine call with source code that
5249 we should not step over. Do step to the first line of code in
5253 handle_step_into_function (struct gdbarch *gdbarch,
5254 struct execution_control_state *ecs)
5257 struct symtab_and_line stop_func_sal, sr_sal;
5259 fill_in_stop_func (gdbarch, ecs);
5261 s = find_pc_symtab (stop_pc);
5262 if (s && s->language != language_asm)
5263 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
5264 ecs->stop_func_start);
5266 stop_func_sal = find_pc_line (ecs->stop_func_start, 0);
5267 /* Use the step_resume_break to step until the end of the prologue,
5268 even if that involves jumps (as it seems to on the vax under
5270 /* If the prologue ends in the middle of a source line, continue to
5271 the end of that source line (if it is still within the function).
5272 Otherwise, just go to end of prologue. */
5273 if (stop_func_sal.end
5274 && stop_func_sal.pc != ecs->stop_func_start
5275 && stop_func_sal.end < ecs->stop_func_end)
5276 ecs->stop_func_start = stop_func_sal.end;
5278 /* Architectures which require breakpoint adjustment might not be able
5279 to place a breakpoint at the computed address. If so, the test
5280 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5281 ecs->stop_func_start to an address at which a breakpoint may be
5282 legitimately placed.
5284 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5285 made, GDB will enter an infinite loop when stepping through
5286 optimized code consisting of VLIW instructions which contain
5287 subinstructions corresponding to different source lines. On
5288 FR-V, it's not permitted to place a breakpoint on any but the
5289 first subinstruction of a VLIW instruction. When a breakpoint is
5290 set, GDB will adjust the breakpoint address to the beginning of
5291 the VLIW instruction. Thus, we need to make the corresponding
5292 adjustment here when computing the stop address. */
5294 if (gdbarch_adjust_breakpoint_address_p (gdbarch))
5296 ecs->stop_func_start
5297 = gdbarch_adjust_breakpoint_address (gdbarch,
5298 ecs->stop_func_start);
5301 if (ecs->stop_func_start == stop_pc)
5303 /* We are already there: stop now. */
5304 ecs->event_thread->control.stop_step = 1;
5305 print_end_stepping_range_reason ();
5306 stop_stepping (ecs);
5311 /* Put the step-breakpoint there and go until there. */
5312 init_sal (&sr_sal); /* initialize to zeroes */
5313 sr_sal.pc = ecs->stop_func_start;
5314 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
5315 sr_sal.pspace = get_frame_program_space (get_current_frame ());
5317 /* Do not specify what the fp should be when we stop since on
5318 some machines the prologue is where the new fp value is
5320 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal, null_frame_id);
5322 /* And make sure stepping stops right away then. */
5323 ecs->event_thread->control.step_range_end
5324 = ecs->event_thread->control.step_range_start;
5329 /* Inferior has stepped backward into a subroutine call with source
5330 code that we should not step over. Do step to the beginning of the
5331 last line of code in it. */
5334 handle_step_into_function_backward (struct gdbarch *gdbarch,
5335 struct execution_control_state *ecs)
5338 struct symtab_and_line stop_func_sal;
5340 fill_in_stop_func (gdbarch, ecs);
5342 s = find_pc_symtab (stop_pc);
5343 if (s && s->language != language_asm)
5344 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
5345 ecs->stop_func_start);
5347 stop_func_sal = find_pc_line (stop_pc, 0);
5349 /* OK, we're just going to keep stepping here. */
5350 if (stop_func_sal.pc == stop_pc)
5352 /* We're there already. Just stop stepping now. */
5353 ecs->event_thread->control.stop_step = 1;
5354 print_end_stepping_range_reason ();
5355 stop_stepping (ecs);
5359 /* Else just reset the step range and keep going.
5360 No step-resume breakpoint, they don't work for
5361 epilogues, which can have multiple entry paths. */
5362 ecs->event_thread->control.step_range_start = stop_func_sal.pc;
5363 ecs->event_thread->control.step_range_end = stop_func_sal.end;
5369 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5370 This is used to both functions and to skip over code. */
5373 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch *gdbarch,
5374 struct symtab_and_line sr_sal,
5375 struct frame_id sr_id,
5376 enum bptype sr_type)
5378 /* There should never be more than one step-resume or longjmp-resume
5379 breakpoint per thread, so we should never be setting a new
5380 step_resume_breakpoint when one is already active. */
5381 gdb_assert (inferior_thread ()->control.step_resume_breakpoint == NULL);
5382 gdb_assert (sr_type == bp_step_resume || sr_type == bp_hp_step_resume);
5385 fprintf_unfiltered (gdb_stdlog,
5386 "infrun: inserting step-resume breakpoint at %s\n",
5387 paddress (gdbarch, sr_sal.pc));
5389 inferior_thread ()->control.step_resume_breakpoint
5390 = set_momentary_breakpoint (gdbarch, sr_sal, sr_id, sr_type);
5394 insert_step_resume_breakpoint_at_sal (struct gdbarch *gdbarch,
5395 struct symtab_and_line sr_sal,
5396 struct frame_id sr_id)
5398 insert_step_resume_breakpoint_at_sal_1 (gdbarch,
5403 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5404 This is used to skip a potential signal handler.
5406 This is called with the interrupted function's frame. The signal
5407 handler, when it returns, will resume the interrupted function at
5411 insert_hp_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
5413 struct symtab_and_line sr_sal;
5414 struct gdbarch *gdbarch;
5416 gdb_assert (return_frame != NULL);
5417 init_sal (&sr_sal); /* initialize to zeros */
5419 gdbarch = get_frame_arch (return_frame);
5420 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch, get_frame_pc (return_frame));
5421 sr_sal.section = find_pc_overlay (sr_sal.pc);
5422 sr_sal.pspace = get_frame_program_space (return_frame);
5424 insert_step_resume_breakpoint_at_sal_1 (gdbarch, sr_sal,
5425 get_stack_frame_id (return_frame),
5429 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5430 is used to skip a function after stepping into it (for "next" or if
5431 the called function has no debugging information).
5433 The current function has almost always been reached by single
5434 stepping a call or return instruction. NEXT_FRAME belongs to the
5435 current function, and the breakpoint will be set at the caller's
5438 This is a separate function rather than reusing
5439 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5440 get_prev_frame, which may stop prematurely (see the implementation
5441 of frame_unwind_caller_id for an example). */
5444 insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame)
5446 struct symtab_and_line sr_sal;
5447 struct gdbarch *gdbarch;
5449 /* We shouldn't have gotten here if we don't know where the call site
5451 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame)));
5453 init_sal (&sr_sal); /* initialize to zeros */
5455 gdbarch = frame_unwind_caller_arch (next_frame);
5456 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch,
5457 frame_unwind_caller_pc (next_frame));
5458 sr_sal.section = find_pc_overlay (sr_sal.pc);
5459 sr_sal.pspace = frame_unwind_program_space (next_frame);
5461 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal,
5462 frame_unwind_caller_id (next_frame));
5465 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5466 new breakpoint at the target of a jmp_buf. The handling of
5467 longjmp-resume uses the same mechanisms used for handling
5468 "step-resume" breakpoints. */
5471 insert_longjmp_resume_breakpoint (struct gdbarch *gdbarch, CORE_ADDR pc)
5473 /* There should never be more than one step-resume or longjmp-resume
5474 breakpoint per thread, so we should never be setting a new
5475 longjmp_resume_breakpoint when one is already active. */
5476 gdb_assert (inferior_thread ()->control.step_resume_breakpoint == NULL);
5479 fprintf_unfiltered (gdb_stdlog,
5480 "infrun: inserting longjmp-resume breakpoint at %s\n",
5481 paddress (gdbarch, pc));
5483 inferior_thread ()->control.step_resume_breakpoint =
5484 set_momentary_breakpoint_at_pc (gdbarch, pc, bp_longjmp_resume);
5487 /* Insert an exception resume breakpoint. TP is the thread throwing
5488 the exception. The block B is the block of the unwinder debug hook
5489 function. FRAME is the frame corresponding to the call to this
5490 function. SYM is the symbol of the function argument holding the
5491 target PC of the exception. */
5494 insert_exception_resume_breakpoint (struct thread_info *tp,
5496 struct frame_info *frame,
5499 struct gdb_exception e;
5501 /* We want to ignore errors here. */
5502 TRY_CATCH (e, RETURN_MASK_ERROR)
5504 struct symbol *vsym;
5505 struct value *value;
5507 struct breakpoint *bp;
5509 vsym = lookup_symbol (SYMBOL_LINKAGE_NAME (sym), b, VAR_DOMAIN, NULL);
5510 value = read_var_value (vsym, frame);
5511 /* If the value was optimized out, revert to the old behavior. */
5512 if (! value_optimized_out (value))
5514 handler = value_as_address (value);
5517 fprintf_unfiltered (gdb_stdlog,
5518 "infrun: exception resume at %lx\n",
5519 (unsigned long) handler);
5521 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
5522 handler, bp_exception_resume);
5523 bp->thread = tp->num;
5524 inferior_thread ()->control.exception_resume_breakpoint = bp;
5529 /* This is called when an exception has been intercepted. Check to
5530 see whether the exception's destination is of interest, and if so,
5531 set an exception resume breakpoint there. */
5534 check_exception_resume (struct execution_control_state *ecs,
5535 struct frame_info *frame, struct symbol *func)
5537 struct gdb_exception e;
5539 TRY_CATCH (e, RETURN_MASK_ERROR)
5542 struct dict_iterator iter;
5546 /* The exception breakpoint is a thread-specific breakpoint on
5547 the unwinder's debug hook, declared as:
5549 void _Unwind_DebugHook (void *cfa, void *handler);
5551 The CFA argument indicates the frame to which control is
5552 about to be transferred. HANDLER is the destination PC.
5554 We ignore the CFA and set a temporary breakpoint at HANDLER.
5555 This is not extremely efficient but it avoids issues in gdb
5556 with computing the DWARF CFA, and it also works even in weird
5557 cases such as throwing an exception from inside a signal
5560 b = SYMBOL_BLOCK_VALUE (func);
5561 ALL_BLOCK_SYMBOLS (b, iter, sym)
5563 if (!SYMBOL_IS_ARGUMENT (sym))
5570 insert_exception_resume_breakpoint (ecs->event_thread,
5579 stop_stepping (struct execution_control_state *ecs)
5582 fprintf_unfiltered (gdb_stdlog, "infrun: stop_stepping\n");
5584 /* Let callers know we don't want to wait for the inferior anymore. */
5585 ecs->wait_some_more = 0;
5588 /* This function handles various cases where we need to continue
5589 waiting for the inferior. */
5590 /* (Used to be the keep_going: label in the old wait_for_inferior). */
5593 keep_going (struct execution_control_state *ecs)
5595 /* Make sure normal_stop is called if we get a QUIT handled before
5597 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
5599 /* Save the pc before execution, to compare with pc after stop. */
5600 ecs->event_thread->prev_pc
5601 = regcache_read_pc (get_thread_regcache (ecs->ptid));
5603 /* If we did not do break;, it means we should keep running the
5604 inferior and not return to debugger. */
5606 if (ecs->event_thread->control.trap_expected
5607 && ecs->event_thread->suspend.stop_signal != TARGET_SIGNAL_TRAP)
5609 /* We took a signal (which we are supposed to pass through to
5610 the inferior, else we'd not get here) and we haven't yet
5611 gotten our trap. Simply continue. */
5613 discard_cleanups (old_cleanups);
5614 resume (currently_stepping (ecs->event_thread),
5615 ecs->event_thread->suspend.stop_signal);
5619 /* Either the trap was not expected, but we are continuing
5620 anyway (the user asked that this signal be passed to the
5623 The signal was SIGTRAP, e.g. it was our signal, but we
5624 decided we should resume from it.
5626 We're going to run this baby now!
5628 Note that insert_breakpoints won't try to re-insert
5629 already inserted breakpoints. Therefore, we don't
5630 care if breakpoints were already inserted, or not. */
5632 if (ecs->event_thread->stepping_over_breakpoint)
5634 struct regcache *thread_regcache = get_thread_regcache (ecs->ptid);
5636 if (!use_displaced_stepping (get_regcache_arch (thread_regcache)))
5637 /* Since we can't do a displaced step, we have to remove
5638 the breakpoint while we step it. To keep things
5639 simple, we remove them all. */
5640 remove_breakpoints ();
5644 struct gdb_exception e;
5646 /* Stop stepping when inserting breakpoints
5648 TRY_CATCH (e, RETURN_MASK_ERROR)
5650 insert_breakpoints ();
5654 exception_print (gdb_stderr, e);
5655 stop_stepping (ecs);
5660 ecs->event_thread->control.trap_expected
5661 = ecs->event_thread->stepping_over_breakpoint;
5663 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
5664 specifies that such a signal should be delivered to the
5667 Typically, this would occure when a user is debugging a
5668 target monitor on a simulator: the target monitor sets a
5669 breakpoint; the simulator encounters this break-point and
5670 halts the simulation handing control to GDB; GDB, noteing
5671 that the break-point isn't valid, returns control back to the
5672 simulator; the simulator then delivers the hardware
5673 equivalent of a SIGNAL_TRAP to the program being debugged. */
5675 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP
5676 && !signal_program[ecs->event_thread->suspend.stop_signal])
5677 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
5679 discard_cleanups (old_cleanups);
5680 resume (currently_stepping (ecs->event_thread),
5681 ecs->event_thread->suspend.stop_signal);
5684 prepare_to_wait (ecs);
5687 /* This function normally comes after a resume, before
5688 handle_inferior_event exits. It takes care of any last bits of
5689 housekeeping, and sets the all-important wait_some_more flag. */
5692 prepare_to_wait (struct execution_control_state *ecs)
5695 fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n");
5697 /* This is the old end of the while loop. Let everybody know we
5698 want to wait for the inferior some more and get called again
5700 ecs->wait_some_more = 1;
5703 /* Several print_*_reason functions to print why the inferior has stopped.
5704 We always print something when the inferior exits, or receives a signal.
5705 The rest of the cases are dealt with later on in normal_stop and
5706 print_it_typical. Ideally there should be a call to one of these
5707 print_*_reason functions functions from handle_inferior_event each time
5708 stop_stepping is called. */
5710 /* Print why the inferior has stopped.
5711 We are done with a step/next/si/ni command, print why the inferior has
5712 stopped. For now print nothing. Print a message only if not in the middle
5713 of doing a "step n" operation for n > 1. */
5716 print_end_stepping_range_reason (void)
5718 if ((!inferior_thread ()->step_multi
5719 || !inferior_thread ()->control.stop_step)
5720 && ui_out_is_mi_like_p (current_uiout))
5721 ui_out_field_string (current_uiout, "reason",
5722 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE));
5725 /* The inferior was terminated by a signal, print why it stopped. */
5728 print_signal_exited_reason (enum target_signal siggnal)
5730 struct ui_out *uiout = current_uiout;
5732 annotate_signalled ();
5733 if (ui_out_is_mi_like_p (uiout))
5735 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED));
5736 ui_out_text (uiout, "\nProgram terminated with signal ");
5737 annotate_signal_name ();
5738 ui_out_field_string (uiout, "signal-name",
5739 target_signal_to_name (siggnal));
5740 annotate_signal_name_end ();
5741 ui_out_text (uiout, ", ");
5742 annotate_signal_string ();
5743 ui_out_field_string (uiout, "signal-meaning",
5744 target_signal_to_string (siggnal));
5745 annotate_signal_string_end ();
5746 ui_out_text (uiout, ".\n");
5747 ui_out_text (uiout, "The program no longer exists.\n");
5750 /* The inferior program is finished, print why it stopped. */
5753 print_exited_reason (int exitstatus)
5755 struct inferior *inf = current_inferior ();
5756 const char *pidstr = target_pid_to_str (pid_to_ptid (inf->pid));
5757 struct ui_out *uiout = current_uiout;
5759 annotate_exited (exitstatus);
5762 if (ui_out_is_mi_like_p (uiout))
5763 ui_out_field_string (uiout, "reason",
5764 async_reason_lookup (EXEC_ASYNC_EXITED));
5765 ui_out_text (uiout, "[Inferior ");
5766 ui_out_text (uiout, plongest (inf->num));
5767 ui_out_text (uiout, " (");
5768 ui_out_text (uiout, pidstr);
5769 ui_out_text (uiout, ") exited with code ");
5770 ui_out_field_fmt (uiout, "exit-code", "0%o", (unsigned int) exitstatus);
5771 ui_out_text (uiout, "]\n");
5775 if (ui_out_is_mi_like_p (uiout))
5777 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY));
5778 ui_out_text (uiout, "[Inferior ");
5779 ui_out_text (uiout, plongest (inf->num));
5780 ui_out_text (uiout, " (");
5781 ui_out_text (uiout, pidstr);
5782 ui_out_text (uiout, ") exited normally]\n");
5784 /* Support the --return-child-result option. */
5785 return_child_result_value = exitstatus;
5788 /* Signal received, print why the inferior has stopped. The signal table
5789 tells us to print about it. */
5792 print_signal_received_reason (enum target_signal siggnal)
5794 struct ui_out *uiout = current_uiout;
5798 if (siggnal == TARGET_SIGNAL_0 && !ui_out_is_mi_like_p (uiout))
5800 struct thread_info *t = inferior_thread ();
5802 ui_out_text (uiout, "\n[");
5803 ui_out_field_string (uiout, "thread-name",
5804 target_pid_to_str (t->ptid));
5805 ui_out_field_fmt (uiout, "thread-id", "] #%d", t->num);
5806 ui_out_text (uiout, " stopped");
5810 ui_out_text (uiout, "\nProgram received signal ");
5811 annotate_signal_name ();
5812 if (ui_out_is_mi_like_p (uiout))
5814 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
5815 ui_out_field_string (uiout, "signal-name",
5816 target_signal_to_name (siggnal));
5817 annotate_signal_name_end ();
5818 ui_out_text (uiout, ", ");
5819 annotate_signal_string ();
5820 ui_out_field_string (uiout, "signal-meaning",
5821 target_signal_to_string (siggnal));
5822 annotate_signal_string_end ();
5824 ui_out_text (uiout, ".\n");
5827 /* Reverse execution: target ran out of history info, print why the inferior
5831 print_no_history_reason (void)
5833 ui_out_text (current_uiout, "\nNo more reverse-execution history.\n");
5836 /* Here to return control to GDB when the inferior stops for real.
5837 Print appropriate messages, remove breakpoints, give terminal our modes.
5839 STOP_PRINT_FRAME nonzero means print the executing frame
5840 (pc, function, args, file, line number and line text).
5841 BREAKPOINTS_FAILED nonzero means stop was due to error
5842 attempting to insert breakpoints. */
5847 struct target_waitstatus last;
5849 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
5851 get_last_target_status (&last_ptid, &last);
5853 /* If an exception is thrown from this point on, make sure to
5854 propagate GDB's knowledge of the executing state to the
5855 frontend/user running state. A QUIT is an easy exception to see
5856 here, so do this before any filtered output. */
5858 make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
5859 else if (last.kind != TARGET_WAITKIND_SIGNALLED
5860 && last.kind != TARGET_WAITKIND_EXITED
5861 && last.kind != TARGET_WAITKIND_NO_RESUMED)
5862 make_cleanup (finish_thread_state_cleanup, &inferior_ptid);
5864 /* In non-stop mode, we don't want GDB to switch threads behind the
5865 user's back, to avoid races where the user is typing a command to
5866 apply to thread x, but GDB switches to thread y before the user
5867 finishes entering the command. */
5869 /* As with the notification of thread events, we want to delay
5870 notifying the user that we've switched thread context until
5871 the inferior actually stops.
5873 There's no point in saying anything if the inferior has exited.
5874 Note that SIGNALLED here means "exited with a signal", not
5875 "received a signal". */
5877 && !ptid_equal (previous_inferior_ptid, inferior_ptid)
5878 && target_has_execution
5879 && last.kind != TARGET_WAITKIND_SIGNALLED
5880 && last.kind != TARGET_WAITKIND_EXITED
5881 && last.kind != TARGET_WAITKIND_NO_RESUMED)
5883 target_terminal_ours_for_output ();
5884 printf_filtered (_("[Switching to %s]\n"),
5885 target_pid_to_str (inferior_ptid));
5886 annotate_thread_changed ();
5887 previous_inferior_ptid = inferior_ptid;
5890 if (last.kind == TARGET_WAITKIND_NO_RESUMED)
5892 gdb_assert (sync_execution || !target_can_async_p ());
5894 target_terminal_ours_for_output ();
5895 printf_filtered (_("No unwaited-for children left.\n"));
5898 if (!breakpoints_always_inserted_mode () && target_has_execution)
5900 if (remove_breakpoints ())
5902 target_terminal_ours_for_output ();
5903 printf_filtered (_("Cannot remove breakpoints because "
5904 "program is no longer writable.\nFurther "
5905 "execution is probably impossible.\n"));
5909 /* If an auto-display called a function and that got a signal,
5910 delete that auto-display to avoid an infinite recursion. */
5912 if (stopped_by_random_signal)
5913 disable_current_display ();
5915 /* Don't print a message if in the middle of doing a "step n"
5916 operation for n > 1 */
5917 if (target_has_execution
5918 && last.kind != TARGET_WAITKIND_SIGNALLED
5919 && last.kind != TARGET_WAITKIND_EXITED
5920 && inferior_thread ()->step_multi
5921 && inferior_thread ()->control.stop_step)
5924 target_terminal_ours ();
5925 async_enable_stdin ();
5927 /* Set the current source location. This will also happen if we
5928 display the frame below, but the current SAL will be incorrect
5929 during a user hook-stop function. */
5930 if (has_stack_frames () && !stop_stack_dummy)
5931 set_current_sal_from_frame (get_current_frame (), 1);
5933 /* Let the user/frontend see the threads as stopped. */
5934 do_cleanups (old_chain);
5936 /* Look up the hook_stop and run it (CLI internally handles problem
5937 of stop_command's pre-hook not existing). */
5939 catch_errors (hook_stop_stub, stop_command,
5940 "Error while running hook_stop:\n", RETURN_MASK_ALL);
5942 if (!has_stack_frames ())
5945 if (last.kind == TARGET_WAITKIND_SIGNALLED
5946 || last.kind == TARGET_WAITKIND_EXITED)
5949 /* Select innermost stack frame - i.e., current frame is frame 0,
5950 and current location is based on that.
5951 Don't do this on return from a stack dummy routine,
5952 or if the program has exited. */
5954 if (!stop_stack_dummy)
5956 select_frame (get_current_frame ());
5958 /* Print current location without a level number, if
5959 we have changed functions or hit a breakpoint.
5960 Print source line if we have one.
5961 bpstat_print() contains the logic deciding in detail
5962 what to print, based on the event(s) that just occurred. */
5964 /* If --batch-silent is enabled then there's no need to print the current
5965 source location, and to try risks causing an error message about
5966 missing source files. */
5967 if (stop_print_frame && !batch_silent)
5971 int do_frame_printing = 1;
5972 struct thread_info *tp = inferior_thread ();
5974 bpstat_ret = bpstat_print (tp->control.stop_bpstat);
5978 /* If we had hit a shared library event breakpoint,
5979 bpstat_print would print out this message. If we hit
5980 an OS-level shared library event, do the same
5982 if (last.kind == TARGET_WAITKIND_LOADED)
5984 printf_filtered (_("Stopped due to shared library event\n"));
5985 source_flag = SRC_LINE; /* something bogus */
5986 do_frame_printing = 0;
5990 /* FIXME: cagney/2002-12-01: Given that a frame ID does
5991 (or should) carry around the function and does (or
5992 should) use that when doing a frame comparison. */
5993 if (tp->control.stop_step
5994 && frame_id_eq (tp->control.step_frame_id,
5995 get_frame_id (get_current_frame ()))
5996 && step_start_function == find_pc_function (stop_pc))
5997 source_flag = SRC_LINE; /* Finished step, just
5998 print source line. */
6000 source_flag = SRC_AND_LOC; /* Print location and
6003 case PRINT_SRC_AND_LOC:
6004 source_flag = SRC_AND_LOC; /* Print location and
6007 case PRINT_SRC_ONLY:
6008 source_flag = SRC_LINE;
6011 source_flag = SRC_LINE; /* something bogus */
6012 do_frame_printing = 0;
6015 internal_error (__FILE__, __LINE__, _("Unknown value."));
6018 /* The behavior of this routine with respect to the source
6020 SRC_LINE: Print only source line
6021 LOCATION: Print only location
6022 SRC_AND_LOC: Print location and source line. */
6023 if (do_frame_printing)
6024 print_stack_frame (get_selected_frame (NULL), 0, source_flag);
6026 /* Display the auto-display expressions. */
6031 /* Save the function value return registers, if we care.
6032 We might be about to restore their previous contents. */
6033 if (inferior_thread ()->control.proceed_to_finish
6034 && execution_direction != EXEC_REVERSE)
6036 /* This should not be necessary. */
6038 regcache_xfree (stop_registers);
6040 /* NB: The copy goes through to the target picking up the value of
6041 all the registers. */
6042 stop_registers = regcache_dup (get_current_regcache ());
6045 if (stop_stack_dummy == STOP_STACK_DUMMY)
6047 /* Pop the empty frame that contains the stack dummy.
6048 This also restores inferior state prior to the call
6049 (struct infcall_suspend_state). */
6050 struct frame_info *frame = get_current_frame ();
6052 gdb_assert (get_frame_type (frame) == DUMMY_FRAME);
6054 /* frame_pop() calls reinit_frame_cache as the last thing it
6055 does which means there's currently no selected frame. We
6056 don't need to re-establish a selected frame if the dummy call
6057 returns normally, that will be done by
6058 restore_infcall_control_state. However, we do have to handle
6059 the case where the dummy call is returning after being
6060 stopped (e.g. the dummy call previously hit a breakpoint).
6061 We can't know which case we have so just always re-establish
6062 a selected frame here. */
6063 select_frame (get_current_frame ());
6067 annotate_stopped ();
6069 /* Suppress the stop observer if we're in the middle of:
6071 - a step n (n > 1), as there still more steps to be done.
6073 - a "finish" command, as the observer will be called in
6074 finish_command_continuation, so it can include the inferior
6075 function's return value.
6077 - calling an inferior function, as we pretend we inferior didn't
6078 run at all. The return value of the call is handled by the
6079 expression evaluator, through call_function_by_hand. */
6081 if (!target_has_execution
6082 || last.kind == TARGET_WAITKIND_SIGNALLED
6083 || last.kind == TARGET_WAITKIND_EXITED
6084 || last.kind == TARGET_WAITKIND_NO_RESUMED
6085 || (!inferior_thread ()->step_multi
6086 && !(inferior_thread ()->control.stop_bpstat
6087 && inferior_thread ()->control.proceed_to_finish)
6088 && !inferior_thread ()->control.in_infcall))
6090 if (!ptid_equal (inferior_ptid, null_ptid))
6091 observer_notify_normal_stop (inferior_thread ()->control.stop_bpstat,
6094 observer_notify_normal_stop (NULL, stop_print_frame);
6097 if (target_has_execution)
6099 if (last.kind != TARGET_WAITKIND_SIGNALLED
6100 && last.kind != TARGET_WAITKIND_EXITED)
6101 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6102 Delete any breakpoint that is to be deleted at the next stop. */
6103 breakpoint_auto_delete (inferior_thread ()->control.stop_bpstat);
6106 /* Try to get rid of automatically added inferiors that are no
6107 longer needed. Keeping those around slows down things linearly.
6108 Note that this never removes the current inferior. */
6113 hook_stop_stub (void *cmd)
6115 execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
6120 signal_stop_state (int signo)
6122 return signal_stop[signo];
6126 signal_print_state (int signo)
6128 return signal_print[signo];
6132 signal_pass_state (int signo)
6134 return signal_program[signo];
6138 signal_cache_update (int signo)
6142 for (signo = 0; signo < (int) TARGET_SIGNAL_LAST; signo++)
6143 signal_cache_update (signo);
6148 signal_pass[signo] = (signal_stop[signo] == 0
6149 && signal_print[signo] == 0
6150 && signal_program[signo] == 1);
6154 signal_stop_update (int signo, int state)
6156 int ret = signal_stop[signo];
6158 signal_stop[signo] = state;
6159 signal_cache_update (signo);
6164 signal_print_update (int signo, int state)
6166 int ret = signal_print[signo];
6168 signal_print[signo] = state;
6169 signal_cache_update (signo);
6174 signal_pass_update (int signo, int state)
6176 int ret = signal_program[signo];
6178 signal_program[signo] = state;
6179 signal_cache_update (signo);
6184 sig_print_header (void)
6186 printf_filtered (_("Signal Stop\tPrint\tPass "
6187 "to program\tDescription\n"));
6191 sig_print_info (enum target_signal oursig)
6193 const char *name = target_signal_to_name (oursig);
6194 int name_padding = 13 - strlen (name);
6196 if (name_padding <= 0)
6199 printf_filtered ("%s", name);
6200 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
6201 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
6202 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
6203 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
6204 printf_filtered ("%s\n", target_signal_to_string (oursig));
6207 /* Specify how various signals in the inferior should be handled. */
6210 handle_command (char *args, int from_tty)
6213 int digits, wordlen;
6214 int sigfirst, signum, siglast;
6215 enum target_signal oursig;
6218 unsigned char *sigs;
6219 struct cleanup *old_chain;
6223 error_no_arg (_("signal to handle"));
6226 /* Allocate and zero an array of flags for which signals to handle. */
6228 nsigs = (int) TARGET_SIGNAL_LAST;
6229 sigs = (unsigned char *) alloca (nsigs);
6230 memset (sigs, 0, nsigs);
6232 /* Break the command line up into args. */
6234 argv = gdb_buildargv (args);
6235 old_chain = make_cleanup_freeargv (argv);
6237 /* Walk through the args, looking for signal oursigs, signal names, and
6238 actions. Signal numbers and signal names may be interspersed with
6239 actions, with the actions being performed for all signals cumulatively
6240 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6242 while (*argv != NULL)
6244 wordlen = strlen (*argv);
6245 for (digits = 0; isdigit ((*argv)[digits]); digits++)
6249 sigfirst = siglast = -1;
6251 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
6253 /* Apply action to all signals except those used by the
6254 debugger. Silently skip those. */
6257 siglast = nsigs - 1;
6259 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
6261 SET_SIGS (nsigs, sigs, signal_stop);
6262 SET_SIGS (nsigs, sigs, signal_print);
6264 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
6266 UNSET_SIGS (nsigs, sigs, signal_program);
6268 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
6270 SET_SIGS (nsigs, sigs, signal_print);
6272 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
6274 SET_SIGS (nsigs, sigs, signal_program);
6276 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
6278 UNSET_SIGS (nsigs, sigs, signal_stop);
6280 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
6282 SET_SIGS (nsigs, sigs, signal_program);
6284 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
6286 UNSET_SIGS (nsigs, sigs, signal_print);
6287 UNSET_SIGS (nsigs, sigs, signal_stop);
6289 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
6291 UNSET_SIGS (nsigs, sigs, signal_program);
6293 else if (digits > 0)
6295 /* It is numeric. The numeric signal refers to our own
6296 internal signal numbering from target.h, not to host/target
6297 signal number. This is a feature; users really should be
6298 using symbolic names anyway, and the common ones like
6299 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6301 sigfirst = siglast = (int)
6302 target_signal_from_command (atoi (*argv));
6303 if ((*argv)[digits] == '-')
6306 target_signal_from_command (atoi ((*argv) + digits + 1));
6308 if (sigfirst > siglast)
6310 /* Bet he didn't figure we'd think of this case... */
6318 oursig = target_signal_from_name (*argv);
6319 if (oursig != TARGET_SIGNAL_UNKNOWN)
6321 sigfirst = siglast = (int) oursig;
6325 /* Not a number and not a recognized flag word => complain. */
6326 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv);
6330 /* If any signal numbers or symbol names were found, set flags for
6331 which signals to apply actions to. */
6333 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
6335 switch ((enum target_signal) signum)
6337 case TARGET_SIGNAL_TRAP:
6338 case TARGET_SIGNAL_INT:
6339 if (!allsigs && !sigs[signum])
6341 if (query (_("%s is used by the debugger.\n\
6342 Are you sure you want to change it? "),
6343 target_signal_to_name ((enum target_signal) signum)))
6349 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6350 gdb_flush (gdb_stdout);
6354 case TARGET_SIGNAL_0:
6355 case TARGET_SIGNAL_DEFAULT:
6356 case TARGET_SIGNAL_UNKNOWN:
6357 /* Make sure that "all" doesn't print these. */
6368 for (signum = 0; signum < nsigs; signum++)
6371 signal_cache_update (-1);
6372 target_pass_signals ((int) TARGET_SIGNAL_LAST, signal_pass);
6376 /* Show the results. */
6377 sig_print_header ();
6378 for (; signum < nsigs; signum++)
6380 sig_print_info (signum);
6386 do_cleanups (old_chain);
6390 xdb_handle_command (char *args, int from_tty)
6393 struct cleanup *old_chain;
6396 error_no_arg (_("xdb command"));
6398 /* Break the command line up into args. */
6400 argv = gdb_buildargv (args);
6401 old_chain = make_cleanup_freeargv (argv);
6402 if (argv[1] != (char *) NULL)
6407 bufLen = strlen (argv[0]) + 20;
6408 argBuf = (char *) xmalloc (bufLen);
6412 enum target_signal oursig;
6414 oursig = target_signal_from_name (argv[0]);
6415 memset (argBuf, 0, bufLen);
6416 if (strcmp (argv[1], "Q") == 0)
6417 sprintf (argBuf, "%s %s", argv[0], "noprint");
6420 if (strcmp (argv[1], "s") == 0)
6422 if (!signal_stop[oursig])
6423 sprintf (argBuf, "%s %s", argv[0], "stop");
6425 sprintf (argBuf, "%s %s", argv[0], "nostop");
6427 else if (strcmp (argv[1], "i") == 0)
6429 if (!signal_program[oursig])
6430 sprintf (argBuf, "%s %s", argv[0], "pass");
6432 sprintf (argBuf, "%s %s", argv[0], "nopass");
6434 else if (strcmp (argv[1], "r") == 0)
6436 if (!signal_print[oursig])
6437 sprintf (argBuf, "%s %s", argv[0], "print");
6439 sprintf (argBuf, "%s %s", argv[0], "noprint");
6445 handle_command (argBuf, from_tty);
6447 printf_filtered (_("Invalid signal handling flag.\n"));
6452 do_cleanups (old_chain);
6455 /* Print current contents of the tables set by the handle command.
6456 It is possible we should just be printing signals actually used
6457 by the current target (but for things to work right when switching
6458 targets, all signals should be in the signal tables). */
6461 signals_info (char *signum_exp, int from_tty)
6463 enum target_signal oursig;
6465 sig_print_header ();
6469 /* First see if this is a symbol name. */
6470 oursig = target_signal_from_name (signum_exp);
6471 if (oursig == TARGET_SIGNAL_UNKNOWN)
6473 /* No, try numeric. */
6475 target_signal_from_command (parse_and_eval_long (signum_exp));
6477 sig_print_info (oursig);
6481 printf_filtered ("\n");
6482 /* These ugly casts brought to you by the native VAX compiler. */
6483 for (oursig = TARGET_SIGNAL_FIRST;
6484 (int) oursig < (int) TARGET_SIGNAL_LAST;
6485 oursig = (enum target_signal) ((int) oursig + 1))
6489 if (oursig != TARGET_SIGNAL_UNKNOWN
6490 && oursig != TARGET_SIGNAL_DEFAULT && oursig != TARGET_SIGNAL_0)
6491 sig_print_info (oursig);
6494 printf_filtered (_("\nUse the \"handle\" command "
6495 "to change these tables.\n"));
6498 /* Check if it makes sense to read $_siginfo from the current thread
6499 at this point. If not, throw an error. */
6502 validate_siginfo_access (void)
6504 /* No current inferior, no siginfo. */
6505 if (ptid_equal (inferior_ptid, null_ptid))
6506 error (_("No thread selected."));
6508 /* Don't try to read from a dead thread. */
6509 if (is_exited (inferior_ptid))
6510 error (_("The current thread has terminated"));
6512 /* ... or from a spinning thread. */
6513 if (is_running (inferior_ptid))
6514 error (_("Selected thread is running."));
6517 /* The $_siginfo convenience variable is a bit special. We don't know
6518 for sure the type of the value until we actually have a chance to
6519 fetch the data. The type can change depending on gdbarch, so it is
6520 also dependent on which thread you have selected.
6522 1. making $_siginfo be an internalvar that creates a new value on
6525 2. making the value of $_siginfo be an lval_computed value. */
6527 /* This function implements the lval_computed support for reading a
6531 siginfo_value_read (struct value *v)
6533 LONGEST transferred;
6535 validate_siginfo_access ();
6538 target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO,
6540 value_contents_all_raw (v),
6542 TYPE_LENGTH (value_type (v)));
6544 if (transferred != TYPE_LENGTH (value_type (v)))
6545 error (_("Unable to read siginfo"));
6548 /* This function implements the lval_computed support for writing a
6552 siginfo_value_write (struct value *v, struct value *fromval)
6554 LONGEST transferred;
6556 validate_siginfo_access ();
6558 transferred = target_write (¤t_target,
6559 TARGET_OBJECT_SIGNAL_INFO,
6561 value_contents_all_raw (fromval),
6563 TYPE_LENGTH (value_type (fromval)));
6565 if (transferred != TYPE_LENGTH (value_type (fromval)))
6566 error (_("Unable to write siginfo"));
6569 static const struct lval_funcs siginfo_value_funcs =
6575 /* Return a new value with the correct type for the siginfo object of
6576 the current thread using architecture GDBARCH. Return a void value
6577 if there's no object available. */
6579 static struct value *
6580 siginfo_make_value (struct gdbarch *gdbarch, struct internalvar *var)
6582 if (target_has_stack
6583 && !ptid_equal (inferior_ptid, null_ptid)
6584 && gdbarch_get_siginfo_type_p (gdbarch))
6586 struct type *type = gdbarch_get_siginfo_type (gdbarch);
6588 return allocate_computed_value (type, &siginfo_value_funcs, NULL);
6591 return allocate_value (builtin_type (gdbarch)->builtin_void);
6595 /* infcall_suspend_state contains state about the program itself like its
6596 registers and any signal it received when it last stopped.
6597 This state must be restored regardless of how the inferior function call
6598 ends (either successfully, or after it hits a breakpoint or signal)
6599 if the program is to properly continue where it left off. */
6601 struct infcall_suspend_state
6603 struct thread_suspend_state thread_suspend;
6604 struct inferior_suspend_state inferior_suspend;
6608 struct regcache *registers;
6610 /* Format of SIGINFO_DATA or NULL if it is not present. */
6611 struct gdbarch *siginfo_gdbarch;
6613 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
6614 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
6615 content would be invalid. */
6616 gdb_byte *siginfo_data;
6619 struct infcall_suspend_state *
6620 save_infcall_suspend_state (void)
6622 struct infcall_suspend_state *inf_state;
6623 struct thread_info *tp = inferior_thread ();
6624 struct inferior *inf = current_inferior ();
6625 struct regcache *regcache = get_current_regcache ();
6626 struct gdbarch *gdbarch = get_regcache_arch (regcache);
6627 gdb_byte *siginfo_data = NULL;
6629 if (gdbarch_get_siginfo_type_p (gdbarch))
6631 struct type *type = gdbarch_get_siginfo_type (gdbarch);
6632 size_t len = TYPE_LENGTH (type);
6633 struct cleanup *back_to;
6635 siginfo_data = xmalloc (len);
6636 back_to = make_cleanup (xfree, siginfo_data);
6638 if (target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
6639 siginfo_data, 0, len) == len)
6640 discard_cleanups (back_to);
6643 /* Errors ignored. */
6644 do_cleanups (back_to);
6645 siginfo_data = NULL;
6649 inf_state = XZALLOC (struct infcall_suspend_state);
6653 inf_state->siginfo_gdbarch = gdbarch;
6654 inf_state->siginfo_data = siginfo_data;
6657 inf_state->thread_suspend = tp->suspend;
6658 inf_state->inferior_suspend = inf->suspend;
6660 /* run_inferior_call will not use the signal due to its `proceed' call with
6661 TARGET_SIGNAL_0 anyway. */
6662 tp->suspend.stop_signal = TARGET_SIGNAL_0;
6664 inf_state->stop_pc = stop_pc;
6666 inf_state->registers = regcache_dup (regcache);
6671 /* Restore inferior session state to INF_STATE. */
6674 restore_infcall_suspend_state (struct infcall_suspend_state *inf_state)
6676 struct thread_info *tp = inferior_thread ();
6677 struct inferior *inf = current_inferior ();
6678 struct regcache *regcache = get_current_regcache ();
6679 struct gdbarch *gdbarch = get_regcache_arch (regcache);
6681 tp->suspend = inf_state->thread_suspend;
6682 inf->suspend = inf_state->inferior_suspend;
6684 stop_pc = inf_state->stop_pc;
6686 if (inf_state->siginfo_gdbarch == gdbarch)
6688 struct type *type = gdbarch_get_siginfo_type (gdbarch);
6689 size_t len = TYPE_LENGTH (type);
6691 /* Errors ignored. */
6692 target_write (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
6693 inf_state->siginfo_data, 0, len);
6696 /* The inferior can be gone if the user types "print exit(0)"
6697 (and perhaps other times). */
6698 if (target_has_execution)
6699 /* NB: The register write goes through to the target. */
6700 regcache_cpy (regcache, inf_state->registers);
6702 discard_infcall_suspend_state (inf_state);
6706 do_restore_infcall_suspend_state_cleanup (void *state)
6708 restore_infcall_suspend_state (state);
6712 make_cleanup_restore_infcall_suspend_state
6713 (struct infcall_suspend_state *inf_state)
6715 return make_cleanup (do_restore_infcall_suspend_state_cleanup, inf_state);
6719 discard_infcall_suspend_state (struct infcall_suspend_state *inf_state)
6721 regcache_xfree (inf_state->registers);
6722 xfree (inf_state->siginfo_data);
6727 get_infcall_suspend_state_regcache (struct infcall_suspend_state *inf_state)
6729 return inf_state->registers;
6732 /* infcall_control_state contains state regarding gdb's control of the
6733 inferior itself like stepping control. It also contains session state like
6734 the user's currently selected frame. */
6736 struct infcall_control_state
6738 struct thread_control_state thread_control;
6739 struct inferior_control_state inferior_control;
6742 enum stop_stack_kind stop_stack_dummy;
6743 int stopped_by_random_signal;
6744 int stop_after_trap;
6746 /* ID if the selected frame when the inferior function call was made. */
6747 struct frame_id selected_frame_id;
6750 /* Save all of the information associated with the inferior<==>gdb
6753 struct infcall_control_state *
6754 save_infcall_control_state (void)
6756 struct infcall_control_state *inf_status = xmalloc (sizeof (*inf_status));
6757 struct thread_info *tp = inferior_thread ();
6758 struct inferior *inf = current_inferior ();
6760 inf_status->thread_control = tp->control;
6761 inf_status->inferior_control = inf->control;
6763 tp->control.step_resume_breakpoint = NULL;
6764 tp->control.exception_resume_breakpoint = NULL;
6766 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
6767 chain. If caller's caller is walking the chain, they'll be happier if we
6768 hand them back the original chain when restore_infcall_control_state is
6770 tp->control.stop_bpstat = bpstat_copy (tp->control.stop_bpstat);
6773 inf_status->stop_stack_dummy = stop_stack_dummy;
6774 inf_status->stopped_by_random_signal = stopped_by_random_signal;
6775 inf_status->stop_after_trap = stop_after_trap;
6777 inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL));
6783 restore_selected_frame (void *args)
6785 struct frame_id *fid = (struct frame_id *) args;
6786 struct frame_info *frame;
6788 frame = frame_find_by_id (*fid);
6790 /* If inf_status->selected_frame_id is NULL, there was no previously
6794 warning (_("Unable to restore previously selected frame."));
6798 select_frame (frame);
6803 /* Restore inferior session state to INF_STATUS. */
6806 restore_infcall_control_state (struct infcall_control_state *inf_status)
6808 struct thread_info *tp = inferior_thread ();
6809 struct inferior *inf = current_inferior ();
6811 if (tp->control.step_resume_breakpoint)
6812 tp->control.step_resume_breakpoint->disposition = disp_del_at_next_stop;
6814 if (tp->control.exception_resume_breakpoint)
6815 tp->control.exception_resume_breakpoint->disposition
6816 = disp_del_at_next_stop;
6818 /* Handle the bpstat_copy of the chain. */
6819 bpstat_clear (&tp->control.stop_bpstat);
6821 tp->control = inf_status->thread_control;
6822 inf->control = inf_status->inferior_control;
6825 stop_stack_dummy = inf_status->stop_stack_dummy;
6826 stopped_by_random_signal = inf_status->stopped_by_random_signal;
6827 stop_after_trap = inf_status->stop_after_trap;
6829 if (target_has_stack)
6831 /* The point of catch_errors is that if the stack is clobbered,
6832 walking the stack might encounter a garbage pointer and
6833 error() trying to dereference it. */
6835 (restore_selected_frame, &inf_status->selected_frame_id,
6836 "Unable to restore previously selected frame:\n",
6837 RETURN_MASK_ERROR) == 0)
6838 /* Error in restoring the selected frame. Select the innermost
6840 select_frame (get_current_frame ());
6847 do_restore_infcall_control_state_cleanup (void *sts)
6849 restore_infcall_control_state (sts);
6853 make_cleanup_restore_infcall_control_state
6854 (struct infcall_control_state *inf_status)
6856 return make_cleanup (do_restore_infcall_control_state_cleanup, inf_status);
6860 discard_infcall_control_state (struct infcall_control_state *inf_status)
6862 if (inf_status->thread_control.step_resume_breakpoint)
6863 inf_status->thread_control.step_resume_breakpoint->disposition
6864 = disp_del_at_next_stop;
6866 if (inf_status->thread_control.exception_resume_breakpoint)
6867 inf_status->thread_control.exception_resume_breakpoint->disposition
6868 = disp_del_at_next_stop;
6870 /* See save_infcall_control_state for info on stop_bpstat. */
6871 bpstat_clear (&inf_status->thread_control.stop_bpstat);
6877 inferior_has_forked (ptid_t pid, ptid_t *child_pid)
6879 struct target_waitstatus last;
6882 get_last_target_status (&last_ptid, &last);
6884 if (last.kind != TARGET_WAITKIND_FORKED)
6887 if (!ptid_equal (last_ptid, pid))
6890 *child_pid = last.value.related_pid;
6895 inferior_has_vforked (ptid_t pid, ptid_t *child_pid)
6897 struct target_waitstatus last;
6900 get_last_target_status (&last_ptid, &last);
6902 if (last.kind != TARGET_WAITKIND_VFORKED)
6905 if (!ptid_equal (last_ptid, pid))
6908 *child_pid = last.value.related_pid;
6913 inferior_has_execd (ptid_t pid, char **execd_pathname)
6915 struct target_waitstatus last;
6918 get_last_target_status (&last_ptid, &last);
6920 if (last.kind != TARGET_WAITKIND_EXECD)
6923 if (!ptid_equal (last_ptid, pid))
6926 *execd_pathname = xstrdup (last.value.execd_pathname);
6931 inferior_has_called_syscall (ptid_t pid, int *syscall_number)
6933 struct target_waitstatus last;
6936 get_last_target_status (&last_ptid, &last);
6938 if (last.kind != TARGET_WAITKIND_SYSCALL_ENTRY &&
6939 last.kind != TARGET_WAITKIND_SYSCALL_RETURN)
6942 if (!ptid_equal (last_ptid, pid))
6945 *syscall_number = last.value.syscall_number;
6950 ptid_match (ptid_t ptid, ptid_t filter)
6952 if (ptid_equal (filter, minus_one_ptid))
6954 if (ptid_is_pid (filter)
6955 && ptid_get_pid (ptid) == ptid_get_pid (filter))
6957 else if (ptid_equal (ptid, filter))
6963 /* restore_inferior_ptid() will be used by the cleanup machinery
6964 to restore the inferior_ptid value saved in a call to
6965 save_inferior_ptid(). */
6968 restore_inferior_ptid (void *arg)
6970 ptid_t *saved_ptid_ptr = arg;
6972 inferior_ptid = *saved_ptid_ptr;
6976 /* Save the value of inferior_ptid so that it may be restored by a
6977 later call to do_cleanups(). Returns the struct cleanup pointer
6978 needed for later doing the cleanup. */
6981 save_inferior_ptid (void)
6983 ptid_t *saved_ptid_ptr;
6985 saved_ptid_ptr = xmalloc (sizeof (ptid_t));
6986 *saved_ptid_ptr = inferior_ptid;
6987 return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
6991 /* User interface for reverse debugging:
6992 Set exec-direction / show exec-direction commands
6993 (returns error unless target implements to_set_exec_direction method). */
6995 int execution_direction = EXEC_FORWARD;
6996 static const char exec_forward[] = "forward";
6997 static const char exec_reverse[] = "reverse";
6998 static const char *exec_direction = exec_forward;
6999 static const char *exec_direction_names[] = {
7006 set_exec_direction_func (char *args, int from_tty,
7007 struct cmd_list_element *cmd)
7009 if (target_can_execute_reverse)
7011 if (!strcmp (exec_direction, exec_forward))
7012 execution_direction = EXEC_FORWARD;
7013 else if (!strcmp (exec_direction, exec_reverse))
7014 execution_direction = EXEC_REVERSE;
7018 exec_direction = exec_forward;
7019 error (_("Target does not support this operation."));
7024 show_exec_direction_func (struct ui_file *out, int from_tty,
7025 struct cmd_list_element *cmd, const char *value)
7027 switch (execution_direction) {
7029 fprintf_filtered (out, _("Forward.\n"));
7032 fprintf_filtered (out, _("Reverse.\n"));
7035 internal_error (__FILE__, __LINE__,
7036 _("bogus execution_direction value: %d"),
7037 (int) execution_direction);
7041 /* User interface for non-stop mode. */
7046 set_non_stop (char *args, int from_tty,
7047 struct cmd_list_element *c)
7049 if (target_has_execution)
7051 non_stop_1 = non_stop;
7052 error (_("Cannot change this setting while the inferior is running."));
7055 non_stop = non_stop_1;
7059 show_non_stop (struct ui_file *file, int from_tty,
7060 struct cmd_list_element *c, const char *value)
7062 fprintf_filtered (file,
7063 _("Controlling the inferior in non-stop mode is %s.\n"),
7068 show_schedule_multiple (struct ui_file *file, int from_tty,
7069 struct cmd_list_element *c, const char *value)
7071 fprintf_filtered (file, _("Resuming the execution of threads "
7072 "of all processes is %s.\n"), value);
7076 _initialize_infrun (void)
7081 add_info ("signals", signals_info, _("\
7082 What debugger does when program gets various signals.\n\
7083 Specify a signal as argument to print info on that signal only."));
7084 add_info_alias ("handle", "signals", 0);
7086 add_com ("handle", class_run, handle_command, _("\
7087 Specify how to handle a signal.\n\
7088 Args are signals and actions to apply to those signals.\n\
7089 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7090 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7091 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7092 The special arg \"all\" is recognized to mean all signals except those\n\
7093 used by the debugger, typically SIGTRAP and SIGINT.\n\
7094 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7095 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7096 Stop means reenter debugger if this signal happens (implies print).\n\
7097 Print means print a message if this signal happens.\n\
7098 Pass means let program see this signal; otherwise program doesn't know.\n\
7099 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7100 Pass and Stop may be combined."));
7103 add_com ("lz", class_info, signals_info, _("\
7104 What debugger does when program gets various signals.\n\
7105 Specify a signal as argument to print info on that signal only."));
7106 add_com ("z", class_run, xdb_handle_command, _("\
7107 Specify how to handle a signal.\n\
7108 Args are signals and actions to apply to those signals.\n\
7109 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7110 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7111 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7112 The special arg \"all\" is recognized to mean all signals except those\n\
7113 used by the debugger, typically SIGTRAP and SIGINT.\n\
7114 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7115 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7116 nopass), \"Q\" (noprint)\n\
7117 Stop means reenter debugger if this signal happens (implies print).\n\
7118 Print means print a message if this signal happens.\n\
7119 Pass means let program see this signal; otherwise program doesn't know.\n\
7120 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7121 Pass and Stop may be combined."));
7125 stop_command = add_cmd ("stop", class_obscure,
7126 not_just_help_class_command, _("\
7127 There is no `stop' command, but you can set a hook on `stop'.\n\
7128 This allows you to set a list of commands to be run each time execution\n\
7129 of the program stops."), &cmdlist);
7131 add_setshow_zinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\
7132 Set inferior debugging."), _("\
7133 Show inferior debugging."), _("\
7134 When non-zero, inferior specific debugging is enabled."),
7137 &setdebuglist, &showdebuglist);
7139 add_setshow_boolean_cmd ("displaced", class_maintenance,
7140 &debug_displaced, _("\
7141 Set displaced stepping debugging."), _("\
7142 Show displaced stepping debugging."), _("\
7143 When non-zero, displaced stepping specific debugging is enabled."),
7145 show_debug_displaced,
7146 &setdebuglist, &showdebuglist);
7148 add_setshow_boolean_cmd ("non-stop", no_class,
7150 Set whether gdb controls the inferior in non-stop mode."), _("\
7151 Show whether gdb controls the inferior in non-stop mode."), _("\
7152 When debugging a multi-threaded program and this setting is\n\
7153 off (the default, also called all-stop mode), when one thread stops\n\
7154 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7155 all other threads in the program while you interact with the thread of\n\
7156 interest. When you continue or step a thread, you can allow the other\n\
7157 threads to run, or have them remain stopped, but while you inspect any\n\
7158 thread's state, all threads stop.\n\
7160 In non-stop mode, when one thread stops, other threads can continue\n\
7161 to run freely. You'll be able to step each thread independently,\n\
7162 leave it stopped or free to run as needed."),
7168 numsigs = (int) TARGET_SIGNAL_LAST;
7169 signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs);
7170 signal_print = (unsigned char *)
7171 xmalloc (sizeof (signal_print[0]) * numsigs);
7172 signal_program = (unsigned char *)
7173 xmalloc (sizeof (signal_program[0]) * numsigs);
7174 signal_pass = (unsigned char *)
7175 xmalloc (sizeof (signal_program[0]) * numsigs);
7176 for (i = 0; i < numsigs; i++)
7179 signal_print[i] = 1;
7180 signal_program[i] = 1;
7183 /* Signals caused by debugger's own actions
7184 should not be given to the program afterwards. */
7185 signal_program[TARGET_SIGNAL_TRAP] = 0;
7186 signal_program[TARGET_SIGNAL_INT] = 0;
7188 /* Signals that are not errors should not normally enter the debugger. */
7189 signal_stop[TARGET_SIGNAL_ALRM] = 0;
7190 signal_print[TARGET_SIGNAL_ALRM] = 0;
7191 signal_stop[TARGET_SIGNAL_VTALRM] = 0;
7192 signal_print[TARGET_SIGNAL_VTALRM] = 0;
7193 signal_stop[TARGET_SIGNAL_PROF] = 0;
7194 signal_print[TARGET_SIGNAL_PROF] = 0;
7195 signal_stop[TARGET_SIGNAL_CHLD] = 0;
7196 signal_print[TARGET_SIGNAL_CHLD] = 0;
7197 signal_stop[TARGET_SIGNAL_IO] = 0;
7198 signal_print[TARGET_SIGNAL_IO] = 0;
7199 signal_stop[TARGET_SIGNAL_POLL] = 0;
7200 signal_print[TARGET_SIGNAL_POLL] = 0;
7201 signal_stop[TARGET_SIGNAL_URG] = 0;
7202 signal_print[TARGET_SIGNAL_URG] = 0;
7203 signal_stop[TARGET_SIGNAL_WINCH] = 0;
7204 signal_print[TARGET_SIGNAL_WINCH] = 0;
7205 signal_stop[TARGET_SIGNAL_PRIO] = 0;
7206 signal_print[TARGET_SIGNAL_PRIO] = 0;
7208 /* These signals are used internally by user-level thread
7209 implementations. (See signal(5) on Solaris.) Like the above
7210 signals, a healthy program receives and handles them as part of
7211 its normal operation. */
7212 signal_stop[TARGET_SIGNAL_LWP] = 0;
7213 signal_print[TARGET_SIGNAL_LWP] = 0;
7214 signal_stop[TARGET_SIGNAL_WAITING] = 0;
7215 signal_print[TARGET_SIGNAL_WAITING] = 0;
7216 signal_stop[TARGET_SIGNAL_CANCEL] = 0;
7217 signal_print[TARGET_SIGNAL_CANCEL] = 0;
7219 /* Update cached state. */
7220 signal_cache_update (-1);
7222 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support,
7223 &stop_on_solib_events, _("\
7224 Set stopping for shared library events."), _("\
7225 Show stopping for shared library events."), _("\
7226 If nonzero, gdb will give control to the user when the dynamic linker\n\
7227 notifies gdb of shared library events. The most common event of interest\n\
7228 to the user would be loading/unloading of a new library."),
7230 show_stop_on_solib_events,
7231 &setlist, &showlist);
7233 add_setshow_enum_cmd ("follow-fork-mode", class_run,
7234 follow_fork_mode_kind_names,
7235 &follow_fork_mode_string, _("\
7236 Set debugger response to a program call of fork or vfork."), _("\
7237 Show debugger response to a program call of fork or vfork."), _("\
7238 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7239 parent - the original process is debugged after a fork\n\
7240 child - the new process is debugged after a fork\n\
7241 The unfollowed process will continue to run.\n\
7242 By default, the debugger will follow the parent process."),
7244 show_follow_fork_mode_string,
7245 &setlist, &showlist);
7247 add_setshow_enum_cmd ("follow-exec-mode", class_run,
7248 follow_exec_mode_names,
7249 &follow_exec_mode_string, _("\
7250 Set debugger response to a program call of exec."), _("\
7251 Show debugger response to a program call of exec."), _("\
7252 An exec call replaces the program image of a process.\n\
7254 follow-exec-mode can be:\n\
7256 new - the debugger creates a new inferior and rebinds the process\n\
7257 to this new inferior. The program the process was running before\n\
7258 the exec call can be restarted afterwards by restarting the original\n\
7261 same - the debugger keeps the process bound to the same inferior.\n\
7262 The new executable image replaces the previous executable loaded in\n\
7263 the inferior. Restarting the inferior after the exec call restarts\n\
7264 the executable the process was running after the exec call.\n\
7266 By default, the debugger will use the same inferior."),
7268 show_follow_exec_mode_string,
7269 &setlist, &showlist);
7271 add_setshow_enum_cmd ("scheduler-locking", class_run,
7272 scheduler_enums, &scheduler_mode, _("\
7273 Set mode for locking scheduler during execution."), _("\
7274 Show mode for locking scheduler during execution."), _("\
7275 off == no locking (threads may preempt at any time)\n\
7276 on == full locking (no thread except the current thread may run)\n\
7277 step == scheduler locked during every single-step operation.\n\
7278 In this mode, no other thread may run during a step command.\n\
7279 Other threads may run while stepping over a function call ('next')."),
7280 set_schedlock_func, /* traps on target vector */
7281 show_scheduler_mode,
7282 &setlist, &showlist);
7284 add_setshow_boolean_cmd ("schedule-multiple", class_run, &sched_multi, _("\
7285 Set mode for resuming threads of all processes."), _("\
7286 Show mode for resuming threads of all processes."), _("\
7287 When on, execution commands (such as 'continue' or 'next') resume all\n\
7288 threads of all processes. When off (which is the default), execution\n\
7289 commands only resume the threads of the current process. The set of\n\
7290 threads that are resumed is further refined by the scheduler-locking\n\
7291 mode (see help set scheduler-locking)."),
7293 show_schedule_multiple,
7294 &setlist, &showlist);
7296 add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\
7297 Set mode of the step operation."), _("\
7298 Show mode of the step operation."), _("\
7299 When set, doing a step over a function without debug line information\n\
7300 will stop at the first instruction of that function. Otherwise, the\n\
7301 function is skipped and the step command stops at a different source line."),
7303 show_step_stop_if_no_debug,
7304 &setlist, &showlist);
7306 add_setshow_enum_cmd ("displaced-stepping", class_run,
7307 can_use_displaced_stepping_enum,
7308 &can_use_displaced_stepping, _("\
7309 Set debugger's willingness to use displaced stepping."), _("\
7310 Show debugger's willingness to use displaced stepping."), _("\
7311 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7312 supported by the target architecture. If off, gdb will not use displaced\n\
7313 stepping to step over breakpoints, even if such is supported by the target\n\
7314 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7315 if the target architecture supports it and non-stop mode is active, but will not\n\
7316 use it in all-stop mode (see help set non-stop)."),
7318 show_can_use_displaced_stepping,
7319 &setlist, &showlist);
7321 add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names,
7322 &exec_direction, _("Set direction of execution.\n\
7323 Options are 'forward' or 'reverse'."),
7324 _("Show direction of execution (forward/reverse)."),
7325 _("Tells gdb whether to execute forward or backward."),
7326 set_exec_direction_func, show_exec_direction_func,
7327 &setlist, &showlist);
7329 /* Set/show detach-on-fork: user-settable mode. */
7331 add_setshow_boolean_cmd ("detach-on-fork", class_run, &detach_fork, _("\
7332 Set whether gdb will detach the child of a fork."), _("\
7333 Show whether gdb will detach the child of a fork."), _("\
7334 Tells gdb whether to detach the child of a fork."),
7335 NULL, NULL, &setlist, &showlist);
7337 /* Set/show disable address space randomization mode. */
7339 add_setshow_boolean_cmd ("disable-randomization", class_support,
7340 &disable_randomization, _("\
7341 Set disabling of debuggee's virtual address space randomization."), _("\
7342 Show disabling of debuggee's virtual address space randomization."), _("\
7343 When this mode is on (which is the default), randomization of the virtual\n\
7344 address space is disabled. Standalone programs run with the randomization\n\
7345 enabled by default on some platforms."),
7346 &set_disable_randomization,
7347 &show_disable_randomization,
7348 &setlist, &showlist);
7350 /* ptid initializations */
7351 inferior_ptid = null_ptid;
7352 target_last_wait_ptid = minus_one_ptid;
7354 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed);
7355 observer_attach_thread_stop_requested (infrun_thread_stop_requested);
7356 observer_attach_thread_exit (infrun_thread_thread_exit);
7357 observer_attach_inferior_exit (infrun_inferior_exit);
7359 /* Explicitly create without lookup, since that tries to create a
7360 value with a void typed value, and when we get here, gdbarch
7361 isn't initialized yet. At this point, we're quite sure there
7362 isn't another convenience variable of the same name. */
7363 create_internalvar_type_lazy ("_siginfo", siginfo_make_value);
7365 add_setshow_boolean_cmd ("observer", no_class,
7366 &observer_mode_1, _("\
7367 Set whether gdb controls the inferior in observer mode."), _("\
7368 Show whether gdb controls the inferior in observer mode."), _("\
7369 In observer mode, GDB can get data from the inferior, but not\n\
7370 affect its execution. Registers and memory may not be changed,\n\
7371 breakpoints may not be set, and the program cannot be interrupted\n\