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"
58 /* Prototypes for local functions */
60 static void signals_info (char *, int);
62 static void handle_command (char *, int);
64 static void sig_print_info (enum target_signal);
66 static void sig_print_header (void);
68 static void resume_cleanups (void *);
70 static int hook_stop_stub (void *);
72 static int restore_selected_frame (void *);
74 static int follow_fork (void);
76 static void set_schedlock_func (char *args, int from_tty,
77 struct cmd_list_element *c);
79 static int currently_stepping (struct thread_info *tp);
81 static int currently_stepping_or_nexting_callback (struct thread_info *tp,
84 static void xdb_handle_command (char *args, int from_tty);
86 static int prepare_to_proceed (int);
88 static void print_exited_reason (int exitstatus);
90 static void print_signal_exited_reason (enum target_signal siggnal);
92 static void print_no_history_reason (void);
94 static void print_signal_received_reason (enum target_signal siggnal);
96 static void print_end_stepping_range_reason (void);
98 void _initialize_infrun (void);
100 void nullify_last_target_wait_ptid (void);
102 /* When set, stop the 'step' command if we enter a function which has
103 no line number information. The normal behavior is that we step
104 over such function. */
105 int step_stop_if_no_debug = 0;
107 show_step_stop_if_no_debug (struct ui_file *file, int from_tty,
108 struct cmd_list_element *c, const char *value)
110 fprintf_filtered (file, _("Mode of the step operation is %s.\n"), value);
113 /* In asynchronous mode, but simulating synchronous execution. */
115 int sync_execution = 0;
117 /* wait_for_inferior and normal_stop use this to notify the user
118 when the inferior stopped in a different thread than it had been
121 static ptid_t previous_inferior_ptid;
123 /* Default behavior is to detach newly forked processes (legacy). */
126 int debug_displaced = 0;
128 show_debug_displaced (struct ui_file *file, int from_tty,
129 struct cmd_list_element *c, const char *value)
131 fprintf_filtered (file, _("Displace stepping debugging is %s.\n"), value);
134 int debug_infrun = 0;
136 show_debug_infrun (struct ui_file *file, int from_tty,
137 struct cmd_list_element *c, const char *value)
139 fprintf_filtered (file, _("Inferior debugging is %s.\n"), value);
142 /* If the program uses ELF-style shared libraries, then calls to
143 functions in shared libraries go through stubs, which live in a
144 table called the PLT (Procedure Linkage Table). The first time the
145 function is called, the stub sends control to the dynamic linker,
146 which looks up the function's real address, patches the stub so
147 that future calls will go directly to the function, and then passes
148 control to the function.
150 If we are stepping at the source level, we don't want to see any of
151 this --- we just want to skip over the stub and the dynamic linker.
152 The simple approach is to single-step until control leaves the
155 However, on some systems (e.g., Red Hat's 5.2 distribution) the
156 dynamic linker calls functions in the shared C library, so you
157 can't tell from the PC alone whether the dynamic linker is still
158 running. In this case, we use a step-resume breakpoint to get us
159 past the dynamic linker, as if we were using "next" to step over a
162 in_solib_dynsym_resolve_code() says whether we're in the dynamic
163 linker code or not. Normally, this means we single-step. However,
164 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
165 address where we can place a step-resume breakpoint to get past the
166 linker's symbol resolution function.
168 in_solib_dynsym_resolve_code() can generally be implemented in a
169 pretty portable way, by comparing the PC against the address ranges
170 of the dynamic linker's sections.
172 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
173 it depends on internal details of the dynamic linker. It's usually
174 not too hard to figure out where to put a breakpoint, but it
175 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
176 sanity checking. If it can't figure things out, returning zero and
177 getting the (possibly confusing) stepping behavior is better than
178 signalling an error, which will obscure the change in the
181 /* This function returns TRUE if pc is the address of an instruction
182 that lies within the dynamic linker (such as the event hook, or the
185 This function must be used only when a dynamic linker event has
186 been caught, and the inferior is being stepped out of the hook, or
187 undefined results are guaranteed. */
189 #ifndef SOLIB_IN_DYNAMIC_LINKER
190 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
193 /* "Observer mode" is somewhat like a more extreme version of
194 non-stop, in which all GDB operations that might affect the
195 target's execution have been disabled. */
197 static int non_stop_1 = 0;
199 int observer_mode = 0;
200 static int observer_mode_1 = 0;
203 set_observer_mode (char *args, int from_tty,
204 struct cmd_list_element *c)
206 extern int pagination_enabled;
208 if (target_has_execution)
210 observer_mode_1 = observer_mode;
211 error (_("Cannot change this setting while the inferior is running."));
214 observer_mode = observer_mode_1;
216 may_write_registers = !observer_mode;
217 may_write_memory = !observer_mode;
218 may_insert_breakpoints = !observer_mode;
219 may_insert_tracepoints = !observer_mode;
220 /* We can insert fast tracepoints in or out of observer mode,
221 but enable them if we're going into this mode. */
223 may_insert_fast_tracepoints = 1;
224 may_stop = !observer_mode;
225 update_target_permissions ();
227 /* Going *into* observer mode we must force non-stop, then
228 going out we leave it that way. */
231 target_async_permitted = 1;
232 pagination_enabled = 0;
233 non_stop = non_stop_1 = 1;
237 printf_filtered (_("Observer mode is now %s.\n"),
238 (observer_mode ? "on" : "off"));
242 show_observer_mode (struct ui_file *file, int from_tty,
243 struct cmd_list_element *c, const char *value)
245 fprintf_filtered (file, _("Observer mode is %s.\n"), value);
248 /* This updates the value of observer mode based on changes in
249 permissions. Note that we are deliberately ignoring the values of
250 may-write-registers and may-write-memory, since the user may have
251 reason to enable these during a session, for instance to turn on a
252 debugging-related global. */
255 update_observer_mode (void)
259 newval = (!may_insert_breakpoints
260 && !may_insert_tracepoints
261 && may_insert_fast_tracepoints
265 /* Let the user know if things change. */
266 if (newval != observer_mode)
267 printf_filtered (_("Observer mode is now %s.\n"),
268 (newval ? "on" : "off"));
270 observer_mode = observer_mode_1 = newval;
273 /* Tables of how to react to signals; the user sets them. */
275 static unsigned char *signal_stop;
276 static unsigned char *signal_print;
277 static unsigned char *signal_program;
279 #define SET_SIGS(nsigs,sigs,flags) \
281 int signum = (nsigs); \
282 while (signum-- > 0) \
283 if ((sigs)[signum]) \
284 (flags)[signum] = 1; \
287 #define UNSET_SIGS(nsigs,sigs,flags) \
289 int signum = (nsigs); \
290 while (signum-- > 0) \
291 if ((sigs)[signum]) \
292 (flags)[signum] = 0; \
295 /* Value to pass to target_resume() to cause all threads to resume. */
297 #define RESUME_ALL minus_one_ptid
299 /* Command list pointer for the "stop" placeholder. */
301 static struct cmd_list_element *stop_command;
303 /* Function inferior was in as of last step command. */
305 static struct symbol *step_start_function;
307 /* Nonzero if we want to give control to the user when we're notified
308 of shared library events by the dynamic linker. */
309 int stop_on_solib_events;
311 show_stop_on_solib_events (struct ui_file *file, int from_tty,
312 struct cmd_list_element *c, const char *value)
314 fprintf_filtered (file, _("Stopping for shared library events is %s.\n"),
318 /* Nonzero means expecting a trace trap
319 and should stop the inferior and return silently when it happens. */
323 /* Save register contents here when executing a "finish" command or are
324 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
325 Thus this contains the return value from the called function (assuming
326 values are returned in a register). */
328 struct regcache *stop_registers;
330 /* Nonzero after stop if current stack frame should be printed. */
332 static int stop_print_frame;
334 /* This is a cached copy of the pid/waitstatus of the last event
335 returned by target_wait()/deprecated_target_wait_hook(). This
336 information is returned by get_last_target_status(). */
337 static ptid_t target_last_wait_ptid;
338 static struct target_waitstatus target_last_waitstatus;
340 static void context_switch (ptid_t ptid);
342 void init_thread_stepping_state (struct thread_info *tss);
344 void init_infwait_state (void);
346 static const char follow_fork_mode_child[] = "child";
347 static const char follow_fork_mode_parent[] = "parent";
349 static const char *follow_fork_mode_kind_names[] = {
350 follow_fork_mode_child,
351 follow_fork_mode_parent,
355 static const char *follow_fork_mode_string = follow_fork_mode_parent;
357 show_follow_fork_mode_string (struct ui_file *file, int from_tty,
358 struct cmd_list_element *c, const char *value)
360 fprintf_filtered (file,
361 _("Debugger response to a program "
362 "call of fork or vfork is \"%s\".\n"),
367 /* Tell the target to follow the fork we're stopped at. Returns true
368 if the inferior should be resumed; false, if the target for some
369 reason decided it's best not to resume. */
374 int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
375 int should_resume = 1;
376 struct thread_info *tp;
378 /* Copy user stepping state to the new inferior thread. FIXME: the
379 followed fork child thread should have a copy of most of the
380 parent thread structure's run control related fields, not just these.
381 Initialized to avoid "may be used uninitialized" warnings from gcc. */
382 struct breakpoint *step_resume_breakpoint = NULL;
383 struct breakpoint *exception_resume_breakpoint = NULL;
384 CORE_ADDR step_range_start = 0;
385 CORE_ADDR step_range_end = 0;
386 struct frame_id step_frame_id = { 0 };
391 struct target_waitstatus wait_status;
393 /* Get the last target status returned by target_wait(). */
394 get_last_target_status (&wait_ptid, &wait_status);
396 /* If not stopped at a fork event, then there's nothing else to
398 if (wait_status.kind != TARGET_WAITKIND_FORKED
399 && wait_status.kind != TARGET_WAITKIND_VFORKED)
402 /* Check if we switched over from WAIT_PTID, since the event was
404 if (!ptid_equal (wait_ptid, minus_one_ptid)
405 && !ptid_equal (inferior_ptid, wait_ptid))
407 /* We did. Switch back to WAIT_PTID thread, to tell the
408 target to follow it (in either direction). We'll
409 afterwards refuse to resume, and inform the user what
411 switch_to_thread (wait_ptid);
416 tp = inferior_thread ();
418 /* If there were any forks/vforks that were caught and are now to be
419 followed, then do so now. */
420 switch (tp->pending_follow.kind)
422 case TARGET_WAITKIND_FORKED:
423 case TARGET_WAITKIND_VFORKED:
425 ptid_t parent, child;
427 /* If the user did a next/step, etc, over a fork call,
428 preserve the stepping state in the fork child. */
429 if (follow_child && should_resume)
431 step_resume_breakpoint = clone_momentary_breakpoint
432 (tp->control.step_resume_breakpoint);
433 step_range_start = tp->control.step_range_start;
434 step_range_end = tp->control.step_range_end;
435 step_frame_id = tp->control.step_frame_id;
436 exception_resume_breakpoint
437 = clone_momentary_breakpoint (tp->control.exception_resume_breakpoint);
439 /* For now, delete the parent's sr breakpoint, otherwise,
440 parent/child sr breakpoints are considered duplicates,
441 and the child version will not be installed. Remove
442 this when the breakpoints module becomes aware of
443 inferiors and address spaces. */
444 delete_step_resume_breakpoint (tp);
445 tp->control.step_range_start = 0;
446 tp->control.step_range_end = 0;
447 tp->control.step_frame_id = null_frame_id;
448 delete_exception_resume_breakpoint (tp);
451 parent = inferior_ptid;
452 child = tp->pending_follow.value.related_pid;
454 /* Tell the target to do whatever is necessary to follow
455 either parent or child. */
456 if (target_follow_fork (follow_child))
458 /* Target refused to follow, or there's some other reason
459 we shouldn't resume. */
464 /* This pending follow fork event is now handled, one way
465 or another. The previous selected thread may be gone
466 from the lists by now, but if it is still around, need
467 to clear the pending follow request. */
468 tp = find_thread_ptid (parent);
470 tp->pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
472 /* This makes sure we don't try to apply the "Switched
473 over from WAIT_PID" logic above. */
474 nullify_last_target_wait_ptid ();
476 /* If we followed the child, switch to it... */
479 switch_to_thread (child);
481 /* ... and preserve the stepping state, in case the
482 user was stepping over the fork call. */
485 tp = inferior_thread ();
486 tp->control.step_resume_breakpoint
487 = step_resume_breakpoint;
488 tp->control.step_range_start = step_range_start;
489 tp->control.step_range_end = step_range_end;
490 tp->control.step_frame_id = step_frame_id;
491 tp->control.exception_resume_breakpoint
492 = exception_resume_breakpoint;
496 /* If we get here, it was because we're trying to
497 resume from a fork catchpoint, but, the user
498 has switched threads away from the thread that
499 forked. In that case, the resume command
500 issued is most likely not applicable to the
501 child, so just warn, and refuse to resume. */
502 warning (_("Not resuming: switched threads "
503 "before following fork child.\n"));
506 /* Reset breakpoints in the child as appropriate. */
507 follow_inferior_reset_breakpoints ();
510 switch_to_thread (parent);
514 case TARGET_WAITKIND_SPURIOUS:
515 /* Nothing to follow. */
518 internal_error (__FILE__, __LINE__,
519 "Unexpected pending_follow.kind %d\n",
520 tp->pending_follow.kind);
524 return should_resume;
528 follow_inferior_reset_breakpoints (void)
530 struct thread_info *tp = inferior_thread ();
532 /* Was there a step_resume breakpoint? (There was if the user
533 did a "next" at the fork() call.) If so, explicitly reset its
536 step_resumes are a form of bp that are made to be per-thread.
537 Since we created the step_resume bp when the parent process
538 was being debugged, and now are switching to the child process,
539 from the breakpoint package's viewpoint, that's a switch of
540 "threads". We must update the bp's notion of which thread
541 it is for, or it'll be ignored when it triggers. */
543 if (tp->control.step_resume_breakpoint)
544 breakpoint_re_set_thread (tp->control.step_resume_breakpoint);
546 if (tp->control.exception_resume_breakpoint)
547 breakpoint_re_set_thread (tp->control.exception_resume_breakpoint);
549 /* Reinsert all breakpoints in the child. The user may have set
550 breakpoints after catching the fork, in which case those
551 were never set in the child, but only in the parent. This makes
552 sure the inserted breakpoints match the breakpoint list. */
554 breakpoint_re_set ();
555 insert_breakpoints ();
558 /* The child has exited or execed: resume threads of the parent the
559 user wanted to be executing. */
562 proceed_after_vfork_done (struct thread_info *thread,
565 int pid = * (int *) arg;
567 if (ptid_get_pid (thread->ptid) == pid
568 && is_running (thread->ptid)
569 && !is_executing (thread->ptid)
570 && !thread->stop_requested
571 && thread->suspend.stop_signal == TARGET_SIGNAL_0)
574 fprintf_unfiltered (gdb_stdlog,
575 "infrun: resuming vfork parent thread %s\n",
576 target_pid_to_str (thread->ptid));
578 switch_to_thread (thread->ptid);
579 clear_proceed_status ();
580 proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 0);
586 /* Called whenever we notice an exec or exit event, to handle
587 detaching or resuming a vfork parent. */
590 handle_vfork_child_exec_or_exit (int exec)
592 struct inferior *inf = current_inferior ();
594 if (inf->vfork_parent)
596 int resume_parent = -1;
598 /* This exec or exit marks the end of the shared memory region
599 between the parent and the child. If the user wanted to
600 detach from the parent, now is the time. */
602 if (inf->vfork_parent->pending_detach)
604 struct thread_info *tp;
605 struct cleanup *old_chain;
606 struct program_space *pspace;
607 struct address_space *aspace;
609 /* follow-fork child, detach-on-fork on. */
611 old_chain = make_cleanup_restore_current_thread ();
613 /* We're letting loose of the parent. */
614 tp = any_live_thread_of_process (inf->vfork_parent->pid);
615 switch_to_thread (tp->ptid);
617 /* We're about to detach from the parent, which implicitly
618 removes breakpoints from its address space. There's a
619 catch here: we want to reuse the spaces for the child,
620 but, parent/child are still sharing the pspace at this
621 point, although the exec in reality makes the kernel give
622 the child a fresh set of new pages. The problem here is
623 that the breakpoints module being unaware of this, would
624 likely chose the child process to write to the parent
625 address space. Swapping the child temporarily away from
626 the spaces has the desired effect. Yes, this is "sort
629 pspace = inf->pspace;
630 aspace = inf->aspace;
634 if (debug_infrun || info_verbose)
636 target_terminal_ours ();
639 fprintf_filtered (gdb_stdlog,
640 "Detaching vfork parent process "
641 "%d after child exec.\n",
642 inf->vfork_parent->pid);
644 fprintf_filtered (gdb_stdlog,
645 "Detaching vfork parent process "
646 "%d after child exit.\n",
647 inf->vfork_parent->pid);
650 target_detach (NULL, 0);
653 inf->pspace = pspace;
654 inf->aspace = aspace;
656 do_cleanups (old_chain);
660 /* We're staying attached to the parent, so, really give the
661 child a new address space. */
662 inf->pspace = add_program_space (maybe_new_address_space ());
663 inf->aspace = inf->pspace->aspace;
665 set_current_program_space (inf->pspace);
667 resume_parent = inf->vfork_parent->pid;
669 /* Break the bonds. */
670 inf->vfork_parent->vfork_child = NULL;
674 struct cleanup *old_chain;
675 struct program_space *pspace;
677 /* If this is a vfork child exiting, then the pspace and
678 aspaces were shared with the parent. Since we're
679 reporting the process exit, we'll be mourning all that is
680 found in the address space, and switching to null_ptid,
681 preparing to start a new inferior. But, since we don't
682 want to clobber the parent's address/program spaces, we
683 go ahead and create a new one for this exiting
686 /* Switch to null_ptid, so that clone_program_space doesn't want
687 to read the selected frame of a dead process. */
688 old_chain = save_inferior_ptid ();
689 inferior_ptid = null_ptid;
691 /* This inferior is dead, so avoid giving the breakpoints
692 module the option to write through to it (cloning a
693 program space resets breakpoints). */
696 pspace = add_program_space (maybe_new_address_space ());
697 set_current_program_space (pspace);
699 clone_program_space (pspace, inf->vfork_parent->pspace);
700 inf->pspace = pspace;
701 inf->aspace = pspace->aspace;
703 /* Put back inferior_ptid. We'll continue mourning this
705 do_cleanups (old_chain);
707 resume_parent = inf->vfork_parent->pid;
708 /* Break the bonds. */
709 inf->vfork_parent->vfork_child = NULL;
712 inf->vfork_parent = NULL;
714 gdb_assert (current_program_space == inf->pspace);
716 if (non_stop && resume_parent != -1)
718 /* If the user wanted the parent to be running, let it go
720 struct cleanup *old_chain = make_cleanup_restore_current_thread ();
723 fprintf_unfiltered (gdb_stdlog,
724 "infrun: resuming vfork parent process %d\n",
727 iterate_over_threads (proceed_after_vfork_done, &resume_parent);
729 do_cleanups (old_chain);
734 /* Enum strings for "set|show displaced-stepping". */
736 static const char follow_exec_mode_new[] = "new";
737 static const char follow_exec_mode_same[] = "same";
738 static const char *follow_exec_mode_names[] =
740 follow_exec_mode_new,
741 follow_exec_mode_same,
745 static const char *follow_exec_mode_string = follow_exec_mode_same;
747 show_follow_exec_mode_string (struct ui_file *file, int from_tty,
748 struct cmd_list_element *c, const char *value)
750 fprintf_filtered (file, _("Follow exec mode is \"%s\".\n"), value);
753 /* EXECD_PATHNAME is assumed to be non-NULL. */
756 follow_exec (ptid_t pid, char *execd_pathname)
758 struct thread_info *th = inferior_thread ();
759 struct inferior *inf = current_inferior ();
761 /* This is an exec event that we actually wish to pay attention to.
762 Refresh our symbol table to the newly exec'd program, remove any
765 If there are breakpoints, they aren't really inserted now,
766 since the exec() transformed our inferior into a fresh set
769 We want to preserve symbolic breakpoints on the list, since
770 we have hopes that they can be reset after the new a.out's
771 symbol table is read.
773 However, any "raw" breakpoints must be removed from the list
774 (e.g., the solib bp's), since their address is probably invalid
777 And, we DON'T want to call delete_breakpoints() here, since
778 that may write the bp's "shadow contents" (the instruction
779 value that was overwritten witha TRAP instruction). Since
780 we now have a new a.out, those shadow contents aren't valid. */
782 mark_breakpoints_out ();
784 update_breakpoints_after_exec ();
786 /* If there was one, it's gone now. We cannot truly step-to-next
787 statement through an exec(). */
788 th->control.step_resume_breakpoint = NULL;
789 th->control.exception_resume_breakpoint = NULL;
790 th->control.step_range_start = 0;
791 th->control.step_range_end = 0;
793 /* The target reports the exec event to the main thread, even if
794 some other thread does the exec, and even if the main thread was
795 already stopped --- if debugging in non-stop mode, it's possible
796 the user had the main thread held stopped in the previous image
797 --- release it now. This is the same behavior as step-over-exec
798 with scheduler-locking on in all-stop mode. */
799 th->stop_requested = 0;
801 /* What is this a.out's name? */
802 printf_unfiltered (_("%s is executing new program: %s\n"),
803 target_pid_to_str (inferior_ptid),
806 /* We've followed the inferior through an exec. Therefore, the
807 inferior has essentially been killed & reborn. */
809 gdb_flush (gdb_stdout);
811 breakpoint_init_inferior (inf_execd);
813 if (gdb_sysroot && *gdb_sysroot)
815 char *name = alloca (strlen (gdb_sysroot)
816 + strlen (execd_pathname)
819 strcpy (name, gdb_sysroot);
820 strcat (name, execd_pathname);
821 execd_pathname = name;
824 /* Reset the shared library package. This ensures that we get a
825 shlib event when the child reaches "_start", at which point the
826 dld will have had a chance to initialize the child. */
827 /* Also, loading a symbol file below may trigger symbol lookups, and
828 we don't want those to be satisfied by the libraries of the
829 previous incarnation of this process. */
830 no_shared_libraries (NULL, 0);
832 if (follow_exec_mode_string == follow_exec_mode_new)
834 struct program_space *pspace;
836 /* The user wants to keep the old inferior and program spaces
837 around. Create a new fresh one, and switch to it. */
839 inf = add_inferior (current_inferior ()->pid);
840 pspace = add_program_space (maybe_new_address_space ());
841 inf->pspace = pspace;
842 inf->aspace = pspace->aspace;
844 exit_inferior_num_silent (current_inferior ()->num);
846 set_current_inferior (inf);
847 set_current_program_space (pspace);
850 gdb_assert (current_program_space == inf->pspace);
852 /* That a.out is now the one to use. */
853 exec_file_attach (execd_pathname, 0);
855 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
856 (Position Independent Executable) main symbol file will get applied by
857 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
858 the breakpoints with the zero displacement. */
860 symbol_file_add (execd_pathname, SYMFILE_MAINLINE | SYMFILE_DEFER_BP_RESET,
863 set_initial_language ();
865 #ifdef SOLIB_CREATE_INFERIOR_HOOK
866 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid));
868 solib_create_inferior_hook (0);
871 jit_inferior_created_hook ();
873 breakpoint_re_set ();
875 /* Reinsert all breakpoints. (Those which were symbolic have
876 been reset to the proper address in the new a.out, thanks
877 to symbol_file_command...). */
878 insert_breakpoints ();
880 /* The next resume of this inferior should bring it to the shlib
881 startup breakpoints. (If the user had also set bp's on
882 "main" from the old (parent) process, then they'll auto-
883 matically get reset there in the new process.). */
886 /* Non-zero if we just simulating a single-step. This is needed
887 because we cannot remove the breakpoints in the inferior process
888 until after the `wait' in `wait_for_inferior'. */
889 static int singlestep_breakpoints_inserted_p = 0;
891 /* The thread we inserted single-step breakpoints for. */
892 static ptid_t singlestep_ptid;
894 /* PC when we started this single-step. */
895 static CORE_ADDR singlestep_pc;
897 /* If another thread hit the singlestep breakpoint, we save the original
898 thread here so that we can resume single-stepping it later. */
899 static ptid_t saved_singlestep_ptid;
900 static int stepping_past_singlestep_breakpoint;
902 /* If not equal to null_ptid, this means that after stepping over breakpoint
903 is finished, we need to switch to deferred_step_ptid, and step it.
905 The use case is when one thread has hit a breakpoint, and then the user
906 has switched to another thread and issued 'step'. We need to step over
907 breakpoint in the thread which hit the breakpoint, but then continue
908 stepping the thread user has selected. */
909 static ptid_t deferred_step_ptid;
911 /* Displaced stepping. */
913 /* In non-stop debugging mode, we must take special care to manage
914 breakpoints properly; in particular, the traditional strategy for
915 stepping a thread past a breakpoint it has hit is unsuitable.
916 'Displaced stepping' is a tactic for stepping one thread past a
917 breakpoint it has hit while ensuring that other threads running
918 concurrently will hit the breakpoint as they should.
920 The traditional way to step a thread T off a breakpoint in a
921 multi-threaded program in all-stop mode is as follows:
923 a0) Initially, all threads are stopped, and breakpoints are not
925 a1) We single-step T, leaving breakpoints uninserted.
926 a2) We insert breakpoints, and resume all threads.
928 In non-stop debugging, however, this strategy is unsuitable: we
929 don't want to have to stop all threads in the system in order to
930 continue or step T past a breakpoint. Instead, we use displaced
933 n0) Initially, T is stopped, other threads are running, and
934 breakpoints are inserted.
935 n1) We copy the instruction "under" the breakpoint to a separate
936 location, outside the main code stream, making any adjustments
937 to the instruction, register, and memory state as directed by
939 n2) We single-step T over the instruction at its new location.
940 n3) We adjust the resulting register and memory state as directed
941 by T's architecture. This includes resetting T's PC to point
942 back into the main instruction stream.
945 This approach depends on the following gdbarch methods:
947 - gdbarch_max_insn_length and gdbarch_displaced_step_location
948 indicate where to copy the instruction, and how much space must
949 be reserved there. We use these in step n1.
951 - gdbarch_displaced_step_copy_insn copies a instruction to a new
952 address, and makes any necessary adjustments to the instruction,
953 register contents, and memory. We use this in step n1.
955 - gdbarch_displaced_step_fixup adjusts registers and memory after
956 we have successfuly single-stepped the instruction, to yield the
957 same effect the instruction would have had if we had executed it
958 at its original address. We use this in step n3.
960 - gdbarch_displaced_step_free_closure provides cleanup.
962 The gdbarch_displaced_step_copy_insn and
963 gdbarch_displaced_step_fixup functions must be written so that
964 copying an instruction with gdbarch_displaced_step_copy_insn,
965 single-stepping across the copied instruction, and then applying
966 gdbarch_displaced_insn_fixup should have the same effects on the
967 thread's memory and registers as stepping the instruction in place
968 would have. Exactly which responsibilities fall to the copy and
969 which fall to the fixup is up to the author of those functions.
971 See the comments in gdbarch.sh for details.
973 Note that displaced stepping and software single-step cannot
974 currently be used in combination, although with some care I think
975 they could be made to. Software single-step works by placing
976 breakpoints on all possible subsequent instructions; if the
977 displaced instruction is a PC-relative jump, those breakpoints
978 could fall in very strange places --- on pages that aren't
979 executable, or at addresses that are not proper instruction
980 boundaries. (We do generally let other threads run while we wait
981 to hit the software single-step breakpoint, and they might
982 encounter such a corrupted instruction.) One way to work around
983 this would be to have gdbarch_displaced_step_copy_insn fully
984 simulate the effect of PC-relative instructions (and return NULL)
985 on architectures that use software single-stepping.
987 In non-stop mode, we can have independent and simultaneous step
988 requests, so more than one thread may need to simultaneously step
989 over a breakpoint. The current implementation assumes there is
990 only one scratch space per process. In this case, we have to
991 serialize access to the scratch space. If thread A wants to step
992 over a breakpoint, but we are currently waiting for some other
993 thread to complete a displaced step, we leave thread A stopped and
994 place it in the displaced_step_request_queue. Whenever a displaced
995 step finishes, we pick the next thread in the queue and start a new
996 displaced step operation on it. See displaced_step_prepare and
997 displaced_step_fixup for details. */
999 struct displaced_step_request
1002 struct displaced_step_request *next;
1005 /* Per-inferior displaced stepping state. */
1006 struct displaced_step_inferior_state
1008 /* Pointer to next in linked list. */
1009 struct displaced_step_inferior_state *next;
1011 /* The process this displaced step state refers to. */
1014 /* A queue of pending displaced stepping requests. One entry per
1015 thread that needs to do a displaced step. */
1016 struct displaced_step_request *step_request_queue;
1018 /* If this is not null_ptid, this is the thread carrying out a
1019 displaced single-step in process PID. This thread's state will
1020 require fixing up once it has completed its step. */
1023 /* The architecture the thread had when we stepped it. */
1024 struct gdbarch *step_gdbarch;
1026 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1027 for post-step cleanup. */
1028 struct displaced_step_closure *step_closure;
1030 /* The address of the original instruction, and the copy we
1032 CORE_ADDR step_original, step_copy;
1034 /* Saved contents of copy area. */
1035 gdb_byte *step_saved_copy;
1038 /* The list of states of processes involved in displaced stepping
1040 static struct displaced_step_inferior_state *displaced_step_inferior_states;
1042 /* Get the displaced stepping state of process PID. */
1044 static struct displaced_step_inferior_state *
1045 get_displaced_stepping_state (int pid)
1047 struct displaced_step_inferior_state *state;
1049 for (state = displaced_step_inferior_states;
1051 state = state->next)
1052 if (state->pid == pid)
1058 /* Add a new displaced stepping state for process PID to the displaced
1059 stepping state list, or return a pointer to an already existing
1060 entry, if it already exists. Never returns NULL. */
1062 static struct displaced_step_inferior_state *
1063 add_displaced_stepping_state (int pid)
1065 struct displaced_step_inferior_state *state;
1067 for (state = displaced_step_inferior_states;
1069 state = state->next)
1070 if (state->pid == pid)
1073 state = xcalloc (1, sizeof (*state));
1075 state->next = displaced_step_inferior_states;
1076 displaced_step_inferior_states = state;
1081 /* If inferior is in displaced stepping, and ADDR equals to starting address
1082 of copy area, return corresponding displaced_step_closure. Otherwise,
1085 struct displaced_step_closure*
1086 get_displaced_step_closure_by_addr (CORE_ADDR addr)
1088 struct displaced_step_inferior_state *displaced
1089 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
1091 /* If checking the mode of displaced instruction in copy area. */
1092 if (displaced && !ptid_equal (displaced->step_ptid, null_ptid)
1093 && (displaced->step_copy == addr))
1094 return displaced->step_closure;
1099 /* Remove the displaced stepping state of process PID. */
1102 remove_displaced_stepping_state (int pid)
1104 struct displaced_step_inferior_state *it, **prev_next_p;
1106 gdb_assert (pid != 0);
1108 it = displaced_step_inferior_states;
1109 prev_next_p = &displaced_step_inferior_states;
1114 *prev_next_p = it->next;
1119 prev_next_p = &it->next;
1125 infrun_inferior_exit (struct inferior *inf)
1127 remove_displaced_stepping_state (inf->pid);
1130 /* Enum strings for "set|show displaced-stepping". */
1132 static const char can_use_displaced_stepping_auto[] = "auto";
1133 static const char can_use_displaced_stepping_on[] = "on";
1134 static const char can_use_displaced_stepping_off[] = "off";
1135 static const char *can_use_displaced_stepping_enum[] =
1137 can_use_displaced_stepping_auto,
1138 can_use_displaced_stepping_on,
1139 can_use_displaced_stepping_off,
1143 /* If ON, and the architecture supports it, GDB will use displaced
1144 stepping to step over breakpoints. If OFF, or if the architecture
1145 doesn't support it, GDB will instead use the traditional
1146 hold-and-step approach. If AUTO (which is the default), GDB will
1147 decide which technique to use to step over breakpoints depending on
1148 which of all-stop or non-stop mode is active --- displaced stepping
1149 in non-stop mode; hold-and-step in all-stop mode. */
1151 static const char *can_use_displaced_stepping =
1152 can_use_displaced_stepping_auto;
1155 show_can_use_displaced_stepping (struct ui_file *file, int from_tty,
1156 struct cmd_list_element *c,
1159 if (can_use_displaced_stepping == can_use_displaced_stepping_auto)
1160 fprintf_filtered (file,
1161 _("Debugger's willingness to use displaced stepping "
1162 "to step over breakpoints is %s (currently %s).\n"),
1163 value, non_stop ? "on" : "off");
1165 fprintf_filtered (file,
1166 _("Debugger's willingness to use displaced stepping "
1167 "to step over breakpoints is %s.\n"), value);
1170 /* Return non-zero if displaced stepping can/should be used to step
1171 over breakpoints. */
1174 use_displaced_stepping (struct gdbarch *gdbarch)
1176 return (((can_use_displaced_stepping == can_use_displaced_stepping_auto
1178 || can_use_displaced_stepping == can_use_displaced_stepping_on)
1179 && gdbarch_displaced_step_copy_insn_p (gdbarch)
1180 && !RECORD_IS_USED);
1183 /* Clean out any stray displaced stepping state. */
1185 displaced_step_clear (struct displaced_step_inferior_state *displaced)
1187 /* Indicate that there is no cleanup pending. */
1188 displaced->step_ptid = null_ptid;
1190 if (displaced->step_closure)
1192 gdbarch_displaced_step_free_closure (displaced->step_gdbarch,
1193 displaced->step_closure);
1194 displaced->step_closure = NULL;
1199 displaced_step_clear_cleanup (void *arg)
1201 struct displaced_step_inferior_state *state = arg;
1203 displaced_step_clear (state);
1206 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1208 displaced_step_dump_bytes (struct ui_file *file,
1209 const gdb_byte *buf,
1214 for (i = 0; i < len; i++)
1215 fprintf_unfiltered (file, "%02x ", buf[i]);
1216 fputs_unfiltered ("\n", file);
1219 /* Prepare to single-step, using displaced stepping.
1221 Note that we cannot use displaced stepping when we have a signal to
1222 deliver. If we have a signal to deliver and an instruction to step
1223 over, then after the step, there will be no indication from the
1224 target whether the thread entered a signal handler or ignored the
1225 signal and stepped over the instruction successfully --- both cases
1226 result in a simple SIGTRAP. In the first case we mustn't do a
1227 fixup, and in the second case we must --- but we can't tell which.
1228 Comments in the code for 'random signals' in handle_inferior_event
1229 explain how we handle this case instead.
1231 Returns 1 if preparing was successful -- this thread is going to be
1232 stepped now; or 0 if displaced stepping this thread got queued. */
1234 displaced_step_prepare (ptid_t ptid)
1236 struct cleanup *old_cleanups, *ignore_cleanups;
1237 struct regcache *regcache = get_thread_regcache (ptid);
1238 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1239 CORE_ADDR original, copy;
1241 struct displaced_step_closure *closure;
1242 struct displaced_step_inferior_state *displaced;
1244 /* We should never reach this function if the architecture does not
1245 support displaced stepping. */
1246 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch));
1248 /* We have to displaced step one thread at a time, as we only have
1249 access to a single scratch space per inferior. */
1251 displaced = add_displaced_stepping_state (ptid_get_pid (ptid));
1253 if (!ptid_equal (displaced->step_ptid, null_ptid))
1255 /* Already waiting for a displaced step to finish. Defer this
1256 request and place in queue. */
1257 struct displaced_step_request *req, *new_req;
1259 if (debug_displaced)
1260 fprintf_unfiltered (gdb_stdlog,
1261 "displaced: defering step of %s\n",
1262 target_pid_to_str (ptid));
1264 new_req = xmalloc (sizeof (*new_req));
1265 new_req->ptid = ptid;
1266 new_req->next = NULL;
1268 if (displaced->step_request_queue)
1270 for (req = displaced->step_request_queue;
1274 req->next = new_req;
1277 displaced->step_request_queue = new_req;
1283 if (debug_displaced)
1284 fprintf_unfiltered (gdb_stdlog,
1285 "displaced: stepping %s now\n",
1286 target_pid_to_str (ptid));
1289 displaced_step_clear (displaced);
1291 old_cleanups = save_inferior_ptid ();
1292 inferior_ptid = ptid;
1294 original = regcache_read_pc (regcache);
1296 copy = gdbarch_displaced_step_location (gdbarch);
1297 len = gdbarch_max_insn_length (gdbarch);
1299 /* Save the original contents of the copy area. */
1300 displaced->step_saved_copy = xmalloc (len);
1301 ignore_cleanups = make_cleanup (free_current_contents,
1302 &displaced->step_saved_copy);
1303 read_memory (copy, displaced->step_saved_copy, len);
1304 if (debug_displaced)
1306 fprintf_unfiltered (gdb_stdlog, "displaced: saved %s: ",
1307 paddress (gdbarch, copy));
1308 displaced_step_dump_bytes (gdb_stdlog,
1309 displaced->step_saved_copy,
1313 closure = gdbarch_displaced_step_copy_insn (gdbarch,
1314 original, copy, regcache);
1316 /* We don't support the fully-simulated case at present. */
1317 gdb_assert (closure);
1319 /* Save the information we need to fix things up if the step
1321 displaced->step_ptid = ptid;
1322 displaced->step_gdbarch = gdbarch;
1323 displaced->step_closure = closure;
1324 displaced->step_original = original;
1325 displaced->step_copy = copy;
1327 make_cleanup (displaced_step_clear_cleanup, displaced);
1329 /* Resume execution at the copy. */
1330 regcache_write_pc (regcache, copy);
1332 discard_cleanups (ignore_cleanups);
1334 do_cleanups (old_cleanups);
1336 if (debug_displaced)
1337 fprintf_unfiltered (gdb_stdlog, "displaced: displaced pc to %s\n",
1338 paddress (gdbarch, copy));
1344 write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr,
1345 const gdb_byte *myaddr, int len)
1347 struct cleanup *ptid_cleanup = save_inferior_ptid ();
1349 inferior_ptid = ptid;
1350 write_memory (memaddr, myaddr, len);
1351 do_cleanups (ptid_cleanup);
1355 displaced_step_fixup (ptid_t event_ptid, enum target_signal signal)
1357 struct cleanup *old_cleanups;
1358 struct displaced_step_inferior_state *displaced
1359 = get_displaced_stepping_state (ptid_get_pid (event_ptid));
1361 /* Was any thread of this process doing a displaced step? */
1362 if (displaced == NULL)
1365 /* Was this event for the pid we displaced? */
1366 if (ptid_equal (displaced->step_ptid, null_ptid)
1367 || ! ptid_equal (displaced->step_ptid, event_ptid))
1370 old_cleanups = make_cleanup (displaced_step_clear_cleanup, displaced);
1372 /* Restore the contents of the copy area. */
1374 ULONGEST len = gdbarch_max_insn_length (displaced->step_gdbarch);
1376 write_memory_ptid (displaced->step_ptid, displaced->step_copy,
1377 displaced->step_saved_copy, len);
1378 if (debug_displaced)
1379 fprintf_unfiltered (gdb_stdlog, "displaced: restored %s\n",
1380 paddress (displaced->step_gdbarch,
1381 displaced->step_copy));
1384 /* Did the instruction complete successfully? */
1385 if (signal == TARGET_SIGNAL_TRAP)
1387 /* Fix up the resulting state. */
1388 gdbarch_displaced_step_fixup (displaced->step_gdbarch,
1389 displaced->step_closure,
1390 displaced->step_original,
1391 displaced->step_copy,
1392 get_thread_regcache (displaced->step_ptid));
1396 /* Since the instruction didn't complete, all we can do is
1398 struct regcache *regcache = get_thread_regcache (event_ptid);
1399 CORE_ADDR pc = regcache_read_pc (regcache);
1401 pc = displaced->step_original + (pc - displaced->step_copy);
1402 regcache_write_pc (regcache, pc);
1405 do_cleanups (old_cleanups);
1407 displaced->step_ptid = null_ptid;
1409 /* Are there any pending displaced stepping requests? If so, run
1410 one now. Leave the state object around, since we're likely to
1411 need it again soon. */
1412 while (displaced->step_request_queue)
1414 struct displaced_step_request *head;
1416 struct regcache *regcache;
1417 struct gdbarch *gdbarch;
1418 CORE_ADDR actual_pc;
1419 struct address_space *aspace;
1421 head = displaced->step_request_queue;
1423 displaced->step_request_queue = head->next;
1426 context_switch (ptid);
1428 regcache = get_thread_regcache (ptid);
1429 actual_pc = regcache_read_pc (regcache);
1430 aspace = get_regcache_aspace (regcache);
1432 if (breakpoint_here_p (aspace, actual_pc))
1434 if (debug_displaced)
1435 fprintf_unfiltered (gdb_stdlog,
1436 "displaced: stepping queued %s now\n",
1437 target_pid_to_str (ptid));
1439 displaced_step_prepare (ptid);
1441 gdbarch = get_regcache_arch (regcache);
1443 if (debug_displaced)
1445 CORE_ADDR actual_pc = regcache_read_pc (regcache);
1448 fprintf_unfiltered (gdb_stdlog, "displaced: run %s: ",
1449 paddress (gdbarch, actual_pc));
1450 read_memory (actual_pc, buf, sizeof (buf));
1451 displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
1454 if (gdbarch_displaced_step_hw_singlestep (gdbarch,
1455 displaced->step_closure))
1456 target_resume (ptid, 1, TARGET_SIGNAL_0);
1458 target_resume (ptid, 0, TARGET_SIGNAL_0);
1460 /* Done, we're stepping a thread. */
1466 struct thread_info *tp = inferior_thread ();
1468 /* The breakpoint we were sitting under has since been
1470 tp->control.trap_expected = 0;
1472 /* Go back to what we were trying to do. */
1473 step = currently_stepping (tp);
1475 if (debug_displaced)
1476 fprintf_unfiltered (gdb_stdlog,
1477 "breakpoint is gone %s: step(%d)\n",
1478 target_pid_to_str (tp->ptid), step);
1480 target_resume (ptid, step, TARGET_SIGNAL_0);
1481 tp->suspend.stop_signal = TARGET_SIGNAL_0;
1483 /* This request was discarded. See if there's any other
1484 thread waiting for its turn. */
1489 /* Update global variables holding ptids to hold NEW_PTID if they were
1490 holding OLD_PTID. */
1492 infrun_thread_ptid_changed (ptid_t old_ptid, ptid_t new_ptid)
1494 struct displaced_step_request *it;
1495 struct displaced_step_inferior_state *displaced;
1497 if (ptid_equal (inferior_ptid, old_ptid))
1498 inferior_ptid = new_ptid;
1500 if (ptid_equal (singlestep_ptid, old_ptid))
1501 singlestep_ptid = new_ptid;
1503 if (ptid_equal (deferred_step_ptid, old_ptid))
1504 deferred_step_ptid = new_ptid;
1506 for (displaced = displaced_step_inferior_states;
1508 displaced = displaced->next)
1510 if (ptid_equal (displaced->step_ptid, old_ptid))
1511 displaced->step_ptid = new_ptid;
1513 for (it = displaced->step_request_queue; it; it = it->next)
1514 if (ptid_equal (it->ptid, old_ptid))
1515 it->ptid = new_ptid;
1522 /* Things to clean up if we QUIT out of resume (). */
1524 resume_cleanups (void *ignore)
1529 static const char schedlock_off[] = "off";
1530 static const char schedlock_on[] = "on";
1531 static const char schedlock_step[] = "step";
1532 static const char *scheduler_enums[] = {
1538 static const char *scheduler_mode = schedlock_off;
1540 show_scheduler_mode (struct ui_file *file, int from_tty,
1541 struct cmd_list_element *c, const char *value)
1543 fprintf_filtered (file,
1544 _("Mode for locking scheduler "
1545 "during execution is \"%s\".\n"),
1550 set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
1552 if (!target_can_lock_scheduler)
1554 scheduler_mode = schedlock_off;
1555 error (_("Target '%s' cannot support this command."), target_shortname);
1559 /* True if execution commands resume all threads of all processes by
1560 default; otherwise, resume only threads of the current inferior
1562 int sched_multi = 0;
1564 /* Try to setup for software single stepping over the specified location.
1565 Return 1 if target_resume() should use hardware single step.
1567 GDBARCH the current gdbarch.
1568 PC the location to step over. */
1571 maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc)
1575 if (execution_direction == EXEC_FORWARD
1576 && gdbarch_software_single_step_p (gdbarch)
1577 && gdbarch_software_single_step (gdbarch, get_current_frame ()))
1580 /* Do not pull these breakpoints until after a `wait' in
1581 `wait_for_inferior'. */
1582 singlestep_breakpoints_inserted_p = 1;
1583 singlestep_ptid = inferior_ptid;
1589 /* Resume the inferior, but allow a QUIT. This is useful if the user
1590 wants to interrupt some lengthy single-stepping operation
1591 (for child processes, the SIGINT goes to the inferior, and so
1592 we get a SIGINT random_signal, but for remote debugging and perhaps
1593 other targets, that's not true).
1595 STEP nonzero if we should step (zero to continue instead).
1596 SIG is the signal to give the inferior (zero for none). */
1598 resume (int step, enum target_signal sig)
1600 int should_resume = 1;
1601 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
1602 struct regcache *regcache = get_current_regcache ();
1603 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1604 struct thread_info *tp = inferior_thread ();
1605 CORE_ADDR pc = regcache_read_pc (regcache);
1606 struct address_space *aspace = get_regcache_aspace (regcache);
1610 if (current_inferior ()->waiting_for_vfork_done)
1612 /* Don't try to single-step a vfork parent that is waiting for
1613 the child to get out of the shared memory region (by exec'ing
1614 or exiting). This is particularly important on software
1615 single-step archs, as the child process would trip on the
1616 software single step breakpoint inserted for the parent
1617 process. Since the parent will not actually execute any
1618 instruction until the child is out of the shared region (such
1619 are vfork's semantics), it is safe to simply continue it.
1620 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
1621 the parent, and tell it to `keep_going', which automatically
1622 re-sets it stepping. */
1624 fprintf_unfiltered (gdb_stdlog,
1625 "infrun: resume : clear step\n");
1630 fprintf_unfiltered (gdb_stdlog,
1631 "infrun: resume (step=%d, signal=%d), "
1632 "trap_expected=%d\n",
1633 step, sig, tp->control.trap_expected);
1635 /* Normally, by the time we reach `resume', the breakpoints are either
1636 removed or inserted, as appropriate. The exception is if we're sitting
1637 at a permanent breakpoint; we need to step over it, but permanent
1638 breakpoints can't be removed. So we have to test for it here. */
1639 if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here)
1641 if (gdbarch_skip_permanent_breakpoint_p (gdbarch))
1642 gdbarch_skip_permanent_breakpoint (gdbarch, regcache);
1645 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1646 how to step past a permanent breakpoint on this architecture. Try using\n\
1647 a command like `return' or `jump' to continue execution."));
1650 /* If enabled, step over breakpoints by executing a copy of the
1651 instruction at a different address.
1653 We can't use displaced stepping when we have a signal to deliver;
1654 the comments for displaced_step_prepare explain why. The
1655 comments in the handle_inferior event for dealing with 'random
1656 signals' explain what we do instead.
1658 We can't use displaced stepping when we are waiting for vfork_done
1659 event, displaced stepping breaks the vfork child similarly as single
1660 step software breakpoint. */
1661 if (use_displaced_stepping (gdbarch)
1662 && (tp->control.trap_expected
1663 || (step && gdbarch_software_single_step_p (gdbarch)))
1664 && sig == TARGET_SIGNAL_0
1665 && !current_inferior ()->waiting_for_vfork_done)
1667 struct displaced_step_inferior_state *displaced;
1669 if (!displaced_step_prepare (inferior_ptid))
1671 /* Got placed in displaced stepping queue. Will be resumed
1672 later when all the currently queued displaced stepping
1673 requests finish. The thread is not executing at this point,
1674 and the call to set_executing will be made later. But we
1675 need to call set_running here, since from frontend point of view,
1676 the thread is running. */
1677 set_running (inferior_ptid, 1);
1678 discard_cleanups (old_cleanups);
1682 displaced = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
1683 step = gdbarch_displaced_step_hw_singlestep (gdbarch,
1684 displaced->step_closure);
1687 /* Do we need to do it the hard way, w/temp breakpoints? */
1689 step = maybe_software_singlestep (gdbarch, pc);
1695 /* If STEP is set, it's a request to use hardware stepping
1696 facilities. But in that case, we should never
1697 use singlestep breakpoint. */
1698 gdb_assert (!(singlestep_breakpoints_inserted_p && step));
1700 /* Decide the set of threads to ask the target to resume. Start
1701 by assuming everything will be resumed, than narrow the set
1702 by applying increasingly restricting conditions. */
1704 /* By default, resume all threads of all processes. */
1705 resume_ptid = RESUME_ALL;
1707 /* Maybe resume only all threads of the current process. */
1708 if (!sched_multi && target_supports_multi_process ())
1710 resume_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
1713 /* Maybe resume a single thread after all. */
1714 if (singlestep_breakpoints_inserted_p
1715 && stepping_past_singlestep_breakpoint)
1717 /* The situation here is as follows. In thread T1 we wanted to
1718 single-step. Lacking hardware single-stepping we've
1719 set breakpoint at the PC of the next instruction -- call it
1720 P. After resuming, we've hit that breakpoint in thread T2.
1721 Now we've removed original breakpoint, inserted breakpoint
1722 at P+1, and try to step to advance T2 past breakpoint.
1723 We need to step only T2, as if T1 is allowed to freely run,
1724 it can run past P, and if other threads are allowed to run,
1725 they can hit breakpoint at P+1, and nested hits of single-step
1726 breakpoints is not something we'd want -- that's complicated
1727 to support, and has no value. */
1728 resume_ptid = inferior_ptid;
1730 else if ((step || singlestep_breakpoints_inserted_p)
1731 && tp->control.trap_expected)
1733 /* We're allowing a thread to run past a breakpoint it has
1734 hit, by single-stepping the thread with the breakpoint
1735 removed. In which case, we need to single-step only this
1736 thread, and keep others stopped, as they can miss this
1737 breakpoint if allowed to run.
1739 The current code actually removes all breakpoints when
1740 doing this, not just the one being stepped over, so if we
1741 let other threads run, we can actually miss any
1742 breakpoint, not just the one at PC. */
1743 resume_ptid = inferior_ptid;
1747 /* With non-stop mode on, threads are always handled
1749 resume_ptid = inferior_ptid;
1751 else if ((scheduler_mode == schedlock_on)
1752 || (scheduler_mode == schedlock_step
1753 && (step || singlestep_breakpoints_inserted_p)))
1755 /* User-settable 'scheduler' mode requires solo thread resume. */
1756 resume_ptid = inferior_ptid;
1759 if (gdbarch_cannot_step_breakpoint (gdbarch))
1761 /* Most targets can step a breakpoint instruction, thus
1762 executing it normally. But if this one cannot, just
1763 continue and we will hit it anyway. */
1764 if (step && breakpoint_inserted_here_p (aspace, pc))
1769 && use_displaced_stepping (gdbarch)
1770 && tp->control.trap_expected)
1772 struct regcache *resume_regcache = get_thread_regcache (resume_ptid);
1773 struct gdbarch *resume_gdbarch = get_regcache_arch (resume_regcache);
1774 CORE_ADDR actual_pc = regcache_read_pc (resume_regcache);
1777 fprintf_unfiltered (gdb_stdlog, "displaced: run %s: ",
1778 paddress (resume_gdbarch, actual_pc));
1779 read_memory (actual_pc, buf, sizeof (buf));
1780 displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
1783 /* Install inferior's terminal modes. */
1784 target_terminal_inferior ();
1786 /* Avoid confusing the next resume, if the next stop/resume
1787 happens to apply to another thread. */
1788 tp->suspend.stop_signal = TARGET_SIGNAL_0;
1790 target_resume (resume_ptid, step, sig);
1793 discard_cleanups (old_cleanups);
1798 /* Clear out all variables saying what to do when inferior is continued.
1799 First do this, then set the ones you want, then call `proceed'. */
1802 clear_proceed_status_thread (struct thread_info *tp)
1805 fprintf_unfiltered (gdb_stdlog,
1806 "infrun: clear_proceed_status_thread (%s)\n",
1807 target_pid_to_str (tp->ptid));
1809 tp->control.trap_expected = 0;
1810 tp->control.step_range_start = 0;
1811 tp->control.step_range_end = 0;
1812 tp->control.step_frame_id = null_frame_id;
1813 tp->control.step_stack_frame_id = null_frame_id;
1814 tp->control.step_over_calls = STEP_OVER_UNDEBUGGABLE;
1815 tp->stop_requested = 0;
1817 tp->control.stop_step = 0;
1819 tp->control.proceed_to_finish = 0;
1821 /* Discard any remaining commands or status from previous stop. */
1822 bpstat_clear (&tp->control.stop_bpstat);
1826 clear_proceed_status_callback (struct thread_info *tp, void *data)
1828 if (is_exited (tp->ptid))
1831 clear_proceed_status_thread (tp);
1836 clear_proceed_status (void)
1840 /* In all-stop mode, delete the per-thread status of all
1841 threads, even if inferior_ptid is null_ptid, there may be
1842 threads on the list. E.g., we may be launching a new
1843 process, while selecting the executable. */
1844 iterate_over_threads (clear_proceed_status_callback, NULL);
1847 if (!ptid_equal (inferior_ptid, null_ptid))
1849 struct inferior *inferior;
1853 /* If in non-stop mode, only delete the per-thread status of
1854 the current thread. */
1855 clear_proceed_status_thread (inferior_thread ());
1858 inferior = current_inferior ();
1859 inferior->control.stop_soon = NO_STOP_QUIETLY;
1862 stop_after_trap = 0;
1864 observer_notify_about_to_proceed ();
1868 regcache_xfree (stop_registers);
1869 stop_registers = NULL;
1873 /* Check the current thread against the thread that reported the most recent
1874 event. If a step-over is required return TRUE and set the current thread
1875 to the old thread. Otherwise return FALSE.
1877 This should be suitable for any targets that support threads. */
1880 prepare_to_proceed (int step)
1883 struct target_waitstatus wait_status;
1884 int schedlock_enabled;
1886 /* With non-stop mode on, threads are always handled individually. */
1887 gdb_assert (! non_stop);
1889 /* Get the last target status returned by target_wait(). */
1890 get_last_target_status (&wait_ptid, &wait_status);
1892 /* Make sure we were stopped at a breakpoint. */
1893 if (wait_status.kind != TARGET_WAITKIND_STOPPED
1894 || (wait_status.value.sig != TARGET_SIGNAL_TRAP
1895 && wait_status.value.sig != TARGET_SIGNAL_ILL
1896 && wait_status.value.sig != TARGET_SIGNAL_SEGV
1897 && wait_status.value.sig != TARGET_SIGNAL_EMT))
1902 schedlock_enabled = (scheduler_mode == schedlock_on
1903 || (scheduler_mode == schedlock_step
1906 /* Don't switch over to WAIT_PTID if scheduler locking is on. */
1907 if (schedlock_enabled)
1910 /* Don't switch over if we're about to resume some other process
1911 other than WAIT_PTID's, and schedule-multiple is off. */
1913 && ptid_get_pid (wait_ptid) != ptid_get_pid (inferior_ptid))
1916 /* Switched over from WAIT_PID. */
1917 if (!ptid_equal (wait_ptid, minus_one_ptid)
1918 && !ptid_equal (inferior_ptid, wait_ptid))
1920 struct regcache *regcache = get_thread_regcache (wait_ptid);
1922 if (breakpoint_here_p (get_regcache_aspace (regcache),
1923 regcache_read_pc (regcache)))
1925 /* If stepping, remember current thread to switch back to. */
1927 deferred_step_ptid = inferior_ptid;
1929 /* Switch back to WAIT_PID thread. */
1930 switch_to_thread (wait_ptid);
1932 /* We return 1 to indicate that there is a breakpoint here,
1933 so we need to step over it before continuing to avoid
1934 hitting it straight away. */
1942 /* Basic routine for continuing the program in various fashions.
1944 ADDR is the address to resume at, or -1 for resume where stopped.
1945 SIGGNAL is the signal to give it, or 0 for none,
1946 or -1 for act according to how it stopped.
1947 STEP is nonzero if should trap after one instruction.
1948 -1 means return after that and print nothing.
1949 You should probably set various step_... variables
1950 before calling here, if you are stepping.
1952 You should call clear_proceed_status before calling proceed. */
1955 proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
1957 struct regcache *regcache;
1958 struct gdbarch *gdbarch;
1959 struct thread_info *tp;
1961 struct address_space *aspace;
1964 /* If we're stopped at a fork/vfork, follow the branch set by the
1965 "set follow-fork-mode" command; otherwise, we'll just proceed
1966 resuming the current thread. */
1967 if (!follow_fork ())
1969 /* The target for some reason decided not to resume. */
1974 regcache = get_current_regcache ();
1975 gdbarch = get_regcache_arch (regcache);
1976 aspace = get_regcache_aspace (regcache);
1977 pc = regcache_read_pc (regcache);
1980 step_start_function = find_pc_function (pc);
1982 stop_after_trap = 1;
1984 if (addr == (CORE_ADDR) -1)
1986 if (pc == stop_pc && breakpoint_here_p (aspace, pc)
1987 && execution_direction != EXEC_REVERSE)
1988 /* There is a breakpoint at the address we will resume at,
1989 step one instruction before inserting breakpoints so that
1990 we do not stop right away (and report a second hit at this
1993 Note, we don't do this in reverse, because we won't
1994 actually be executing the breakpoint insn anyway.
1995 We'll be (un-)executing the previous instruction. */
1998 else if (gdbarch_single_step_through_delay_p (gdbarch)
1999 && gdbarch_single_step_through_delay (gdbarch,
2000 get_current_frame ()))
2001 /* We stepped onto an instruction that needs to be stepped
2002 again before re-inserting the breakpoint, do so. */
2007 regcache_write_pc (regcache, addr);
2011 fprintf_unfiltered (gdb_stdlog,
2012 "infrun: proceed (addr=%s, signal=%d, step=%d)\n",
2013 paddress (gdbarch, addr), siggnal, step);
2016 /* In non-stop, each thread is handled individually. The context
2017 must already be set to the right thread here. */
2021 /* In a multi-threaded task we may select another thread and
2022 then continue or step.
2024 But if the old thread was stopped at a breakpoint, it will
2025 immediately cause another breakpoint stop without any
2026 execution (i.e. it will report a breakpoint hit incorrectly).
2027 So we must step over it first.
2029 prepare_to_proceed checks the current thread against the
2030 thread that reported the most recent event. If a step-over
2031 is required it returns TRUE and sets the current thread to
2033 if (prepare_to_proceed (step))
2037 /* prepare_to_proceed may change the current thread. */
2038 tp = inferior_thread ();
2042 tp->control.trap_expected = 1;
2043 /* If displaced stepping is enabled, we can step over the
2044 breakpoint without hitting it, so leave all breakpoints
2045 inserted. Otherwise we need to disable all breakpoints, step
2046 one instruction, and then re-add them when that step is
2048 if (!use_displaced_stepping (gdbarch))
2049 remove_breakpoints ();
2052 /* We can insert breakpoints if we're not trying to step over one,
2053 or if we are stepping over one but we're using displaced stepping
2055 if (! tp->control.trap_expected || use_displaced_stepping (gdbarch))
2056 insert_breakpoints ();
2060 /* Pass the last stop signal to the thread we're resuming,
2061 irrespective of whether the current thread is the thread that
2062 got the last event or not. This was historically GDB's
2063 behaviour before keeping a stop_signal per thread. */
2065 struct thread_info *last_thread;
2067 struct target_waitstatus last_status;
2069 get_last_target_status (&last_ptid, &last_status);
2070 if (!ptid_equal (inferior_ptid, last_ptid)
2071 && !ptid_equal (last_ptid, null_ptid)
2072 && !ptid_equal (last_ptid, minus_one_ptid))
2074 last_thread = find_thread_ptid (last_ptid);
2077 tp->suspend.stop_signal = last_thread->suspend.stop_signal;
2078 last_thread->suspend.stop_signal = TARGET_SIGNAL_0;
2083 if (siggnal != TARGET_SIGNAL_DEFAULT)
2084 tp->suspend.stop_signal = siggnal;
2085 /* If this signal should not be seen by program,
2086 give it zero. Used for debugging signals. */
2087 else if (!signal_program[tp->suspend.stop_signal])
2088 tp->suspend.stop_signal = TARGET_SIGNAL_0;
2090 annotate_starting ();
2092 /* Make sure that output from GDB appears before output from the
2094 gdb_flush (gdb_stdout);
2096 /* Refresh prev_pc value just prior to resuming. This used to be
2097 done in stop_stepping, however, setting prev_pc there did not handle
2098 scenarios such as inferior function calls or returning from
2099 a function via the return command. In those cases, the prev_pc
2100 value was not set properly for subsequent commands. The prev_pc value
2101 is used to initialize the starting line number in the ecs. With an
2102 invalid value, the gdb next command ends up stopping at the position
2103 represented by the next line table entry past our start position.
2104 On platforms that generate one line table entry per line, this
2105 is not a problem. However, on the ia64, the compiler generates
2106 extraneous line table entries that do not increase the line number.
2107 When we issue the gdb next command on the ia64 after an inferior call
2108 or a return command, we often end up a few instructions forward, still
2109 within the original line we started.
2111 An attempt was made to refresh the prev_pc at the same time the
2112 execution_control_state is initialized (for instance, just before
2113 waiting for an inferior event). But this approach did not work
2114 because of platforms that use ptrace, where the pc register cannot
2115 be read unless the inferior is stopped. At that point, we are not
2116 guaranteed the inferior is stopped and so the regcache_read_pc() call
2117 can fail. Setting the prev_pc value here ensures the value is updated
2118 correctly when the inferior is stopped. */
2119 tp->prev_pc = regcache_read_pc (get_current_regcache ());
2121 /* Fill in with reasonable starting values. */
2122 init_thread_stepping_state (tp);
2124 /* Reset to normal state. */
2125 init_infwait_state ();
2127 /* Resume inferior. */
2128 resume (oneproc || step || bpstat_should_step (), tp->suspend.stop_signal);
2130 /* Wait for it to stop (if not standalone)
2131 and in any case decode why it stopped, and act accordingly. */
2132 /* Do this only if we are not using the event loop, or if the target
2133 does not support asynchronous execution. */
2134 if (!target_can_async_p ())
2136 wait_for_inferior (0);
2142 /* Start remote-debugging of a machine over a serial link. */
2145 start_remote (int from_tty)
2147 struct inferior *inferior;
2149 init_wait_for_inferior ();
2150 inferior = current_inferior ();
2151 inferior->control.stop_soon = STOP_QUIETLY_REMOTE;
2153 /* Always go on waiting for the target, regardless of the mode. */
2154 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2155 indicate to wait_for_inferior that a target should timeout if
2156 nothing is returned (instead of just blocking). Because of this,
2157 targets expecting an immediate response need to, internally, set
2158 things up so that the target_wait() is forced to eventually
2160 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2161 differentiate to its caller what the state of the target is after
2162 the initial open has been performed. Here we're assuming that
2163 the target has stopped. It should be possible to eventually have
2164 target_open() return to the caller an indication that the target
2165 is currently running and GDB state should be set to the same as
2166 for an async run. */
2167 wait_for_inferior (0);
2169 /* Now that the inferior has stopped, do any bookkeeping like
2170 loading shared libraries. We want to do this before normal_stop,
2171 so that the displayed frame is up to date. */
2172 post_create_inferior (¤t_target, from_tty);
2177 /* Initialize static vars when a new inferior begins. */
2180 init_wait_for_inferior (void)
2182 /* These are meaningless until the first time through wait_for_inferior. */
2184 breakpoint_init_inferior (inf_starting);
2186 clear_proceed_status ();
2188 stepping_past_singlestep_breakpoint = 0;
2189 deferred_step_ptid = null_ptid;
2191 target_last_wait_ptid = minus_one_ptid;
2193 previous_inferior_ptid = null_ptid;
2194 init_infwait_state ();
2196 /* Discard any skipped inlined frames. */
2197 clear_inline_frame_state (minus_one_ptid);
2201 /* This enum encodes possible reasons for doing a target_wait, so that
2202 wfi can call target_wait in one place. (Ultimately the call will be
2203 moved out of the infinite loop entirely.) */
2207 infwait_normal_state,
2208 infwait_thread_hop_state,
2209 infwait_step_watch_state,
2210 infwait_nonstep_watch_state
2213 /* The PTID we'll do a target_wait on.*/
2216 /* Current inferior wait state. */
2217 enum infwait_states infwait_state;
2219 /* Data to be passed around while handling an event. This data is
2220 discarded between events. */
2221 struct execution_control_state
2224 /* The thread that got the event, if this was a thread event; NULL
2226 struct thread_info *event_thread;
2228 struct target_waitstatus ws;
2230 CORE_ADDR stop_func_start;
2231 CORE_ADDR stop_func_end;
2232 char *stop_func_name;
2233 int new_thread_event;
2237 static void handle_inferior_event (struct execution_control_state *ecs);
2239 static void handle_step_into_function (struct gdbarch *gdbarch,
2240 struct execution_control_state *ecs);
2241 static void handle_step_into_function_backward (struct gdbarch *gdbarch,
2242 struct execution_control_state *ecs);
2243 static void insert_step_resume_breakpoint_at_frame (struct frame_info *);
2244 static void insert_step_resume_breakpoint_at_caller (struct frame_info *);
2245 static void insert_step_resume_breakpoint_at_sal (struct gdbarch *,
2246 struct symtab_and_line ,
2248 static void insert_longjmp_resume_breakpoint (struct gdbarch *, CORE_ADDR);
2249 static void check_exception_resume (struct execution_control_state *,
2250 struct frame_info *, struct symbol *);
2252 static void stop_stepping (struct execution_control_state *ecs);
2253 static void prepare_to_wait (struct execution_control_state *ecs);
2254 static void keep_going (struct execution_control_state *ecs);
2256 /* Callback for iterate over threads. If the thread is stopped, but
2257 the user/frontend doesn't know about that yet, go through
2258 normal_stop, as if the thread had just stopped now. ARG points at
2259 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2260 ptid_is_pid(PTID) is true, applies to all threads of the process
2261 pointed at by PTID. Otherwise, apply only to the thread pointed by
2265 infrun_thread_stop_requested_callback (struct thread_info *info, void *arg)
2267 ptid_t ptid = * (ptid_t *) arg;
2269 if ((ptid_equal (info->ptid, ptid)
2270 || ptid_equal (minus_one_ptid, ptid)
2271 || (ptid_is_pid (ptid)
2272 && ptid_get_pid (ptid) == ptid_get_pid (info->ptid)))
2273 && is_running (info->ptid)
2274 && !is_executing (info->ptid))
2276 struct cleanup *old_chain;
2277 struct execution_control_state ecss;
2278 struct execution_control_state *ecs = &ecss;
2280 memset (ecs, 0, sizeof (*ecs));
2282 old_chain = make_cleanup_restore_current_thread ();
2284 switch_to_thread (info->ptid);
2286 /* Go through handle_inferior_event/normal_stop, so we always
2287 have consistent output as if the stop event had been
2289 ecs->ptid = info->ptid;
2290 ecs->event_thread = find_thread_ptid (info->ptid);
2291 ecs->ws.kind = TARGET_WAITKIND_STOPPED;
2292 ecs->ws.value.sig = TARGET_SIGNAL_0;
2294 handle_inferior_event (ecs);
2296 if (!ecs->wait_some_more)
2298 struct thread_info *tp;
2302 /* Finish off the continuations. The continations
2303 themselves are responsible for realising the thread
2304 didn't finish what it was supposed to do. */
2305 tp = inferior_thread ();
2306 do_all_intermediate_continuations_thread (tp);
2307 do_all_continuations_thread (tp);
2310 do_cleanups (old_chain);
2316 /* This function is attached as a "thread_stop_requested" observer.
2317 Cleanup local state that assumed the PTID was to be resumed, and
2318 report the stop to the frontend. */
2321 infrun_thread_stop_requested (ptid_t ptid)
2323 struct displaced_step_inferior_state *displaced;
2325 /* PTID was requested to stop. Remove it from the displaced
2326 stepping queue, so we don't try to resume it automatically. */
2328 for (displaced = displaced_step_inferior_states;
2330 displaced = displaced->next)
2332 struct displaced_step_request *it, **prev_next_p;
2334 it = displaced->step_request_queue;
2335 prev_next_p = &displaced->step_request_queue;
2338 if (ptid_match (it->ptid, ptid))
2340 *prev_next_p = it->next;
2346 prev_next_p = &it->next;
2353 iterate_over_threads (infrun_thread_stop_requested_callback, &ptid);
2357 infrun_thread_thread_exit (struct thread_info *tp, int silent)
2359 if (ptid_equal (target_last_wait_ptid, tp->ptid))
2360 nullify_last_target_wait_ptid ();
2363 /* Callback for iterate_over_threads. */
2366 delete_step_resume_breakpoint_callback (struct thread_info *info, void *data)
2368 if (is_exited (info->ptid))
2371 delete_step_resume_breakpoint (info);
2372 delete_exception_resume_breakpoint (info);
2376 /* In all-stop, delete the step resume breakpoint of any thread that
2377 had one. In non-stop, delete the step resume breakpoint of the
2378 thread that just stopped. */
2381 delete_step_thread_step_resume_breakpoint (void)
2383 if (!target_has_execution
2384 || ptid_equal (inferior_ptid, null_ptid))
2385 /* If the inferior has exited, we have already deleted the step
2386 resume breakpoints out of GDB's lists. */
2391 /* If in non-stop mode, only delete the step-resume or
2392 longjmp-resume breakpoint of the thread that just stopped
2394 struct thread_info *tp = inferior_thread ();
2396 delete_step_resume_breakpoint (tp);
2397 delete_exception_resume_breakpoint (tp);
2400 /* In all-stop mode, delete all step-resume and longjmp-resume
2401 breakpoints of any thread that had them. */
2402 iterate_over_threads (delete_step_resume_breakpoint_callback, NULL);
2405 /* A cleanup wrapper. */
2408 delete_step_thread_step_resume_breakpoint_cleanup (void *arg)
2410 delete_step_thread_step_resume_breakpoint ();
2413 /* Pretty print the results of target_wait, for debugging purposes. */
2416 print_target_wait_results (ptid_t waiton_ptid, ptid_t result_ptid,
2417 const struct target_waitstatus *ws)
2419 char *status_string = target_waitstatus_to_string (ws);
2420 struct ui_file *tmp_stream = mem_fileopen ();
2423 /* The text is split over several lines because it was getting too long.
2424 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2425 output as a unit; we want only one timestamp printed if debug_timestamp
2428 fprintf_unfiltered (tmp_stream,
2429 "infrun: target_wait (%d", PIDGET (waiton_ptid));
2430 if (PIDGET (waiton_ptid) != -1)
2431 fprintf_unfiltered (tmp_stream,
2432 " [%s]", target_pid_to_str (waiton_ptid));
2433 fprintf_unfiltered (tmp_stream, ", status) =\n");
2434 fprintf_unfiltered (tmp_stream,
2435 "infrun: %d [%s],\n",
2436 PIDGET (result_ptid), target_pid_to_str (result_ptid));
2437 fprintf_unfiltered (tmp_stream,
2441 text = ui_file_xstrdup (tmp_stream, NULL);
2443 /* This uses %s in part to handle %'s in the text, but also to avoid
2444 a gcc error: the format attribute requires a string literal. */
2445 fprintf_unfiltered (gdb_stdlog, "%s", text);
2447 xfree (status_string);
2449 ui_file_delete (tmp_stream);
2452 /* Prepare and stabilize the inferior for detaching it. E.g.,
2453 detaching while a thread is displaced stepping is a recipe for
2454 crashing it, as nothing would readjust the PC out of the scratch
2458 prepare_for_detach (void)
2460 struct inferior *inf = current_inferior ();
2461 ptid_t pid_ptid = pid_to_ptid (inf->pid);
2462 struct cleanup *old_chain_1;
2463 struct displaced_step_inferior_state *displaced;
2465 displaced = get_displaced_stepping_state (inf->pid);
2467 /* Is any thread of this process displaced stepping? If not,
2468 there's nothing else to do. */
2469 if (displaced == NULL || ptid_equal (displaced->step_ptid, null_ptid))
2473 fprintf_unfiltered (gdb_stdlog,
2474 "displaced-stepping in-process while detaching");
2476 old_chain_1 = make_cleanup_restore_integer (&inf->detaching);
2479 while (!ptid_equal (displaced->step_ptid, null_ptid))
2481 struct cleanup *old_chain_2;
2482 struct execution_control_state ecss;
2483 struct execution_control_state *ecs;
2486 memset (ecs, 0, sizeof (*ecs));
2488 overlay_cache_invalid = 1;
2490 /* We have to invalidate the registers BEFORE calling
2491 target_wait because they can be loaded from the target while
2492 in target_wait. This makes remote debugging a bit more
2493 efficient for those targets that provide critical registers
2494 as part of their normal status mechanism. */
2496 registers_changed ();
2498 if (deprecated_target_wait_hook)
2499 ecs->ptid = deprecated_target_wait_hook (pid_ptid, &ecs->ws, 0);
2501 ecs->ptid = target_wait (pid_ptid, &ecs->ws, 0);
2504 print_target_wait_results (pid_ptid, ecs->ptid, &ecs->ws);
2506 /* If an error happens while handling the event, propagate GDB's
2507 knowledge of the executing state to the frontend/user running
2509 old_chain_2 = make_cleanup (finish_thread_state_cleanup,
2512 /* In non-stop mode, each thread is handled individually.
2513 Switch early, so the global state is set correctly for this
2516 && ecs->ws.kind != TARGET_WAITKIND_EXITED
2517 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
2518 context_switch (ecs->ptid);
2520 /* Now figure out what to do with the result of the result. */
2521 handle_inferior_event (ecs);
2523 /* No error, don't finish the state yet. */
2524 discard_cleanups (old_chain_2);
2526 /* Breakpoints and watchpoints are not installed on the target
2527 at this point, and signals are passed directly to the
2528 inferior, so this must mean the process is gone. */
2529 if (!ecs->wait_some_more)
2531 discard_cleanups (old_chain_1);
2532 error (_("Program exited while detaching"));
2536 discard_cleanups (old_chain_1);
2539 /* Wait for control to return from inferior to debugger.
2541 If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
2542 as if they were SIGTRAP signals. This can be useful during
2543 the startup sequence on some targets such as HP/UX, where
2544 we receive an EXEC event instead of the expected SIGTRAP.
2546 If inferior gets a signal, we may decide to start it up again
2547 instead of returning. That is why there is a loop in this function.
2548 When this function actually returns it means the inferior
2549 should be left stopped and GDB should read more commands. */
2552 wait_for_inferior (int treat_exec_as_sigtrap)
2554 struct cleanup *old_cleanups;
2555 struct execution_control_state ecss;
2556 struct execution_control_state *ecs;
2560 (gdb_stdlog, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
2561 treat_exec_as_sigtrap);
2564 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup, NULL);
2567 memset (ecs, 0, sizeof (*ecs));
2569 /* We'll update this if & when we switch to a new thread. */
2570 previous_inferior_ptid = inferior_ptid;
2574 struct cleanup *old_chain;
2576 /* We have to invalidate the registers BEFORE calling target_wait
2577 because they can be loaded from the target while in target_wait.
2578 This makes remote debugging a bit more efficient for those
2579 targets that provide critical registers as part of their normal
2580 status mechanism. */
2582 overlay_cache_invalid = 1;
2583 registers_changed ();
2585 if (deprecated_target_wait_hook)
2586 ecs->ptid = deprecated_target_wait_hook (waiton_ptid, &ecs->ws, 0);
2588 ecs->ptid = target_wait (waiton_ptid, &ecs->ws, 0);
2591 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
2593 if (treat_exec_as_sigtrap && ecs->ws.kind == TARGET_WAITKIND_EXECD)
2595 xfree (ecs->ws.value.execd_pathname);
2596 ecs->ws.kind = TARGET_WAITKIND_STOPPED;
2597 ecs->ws.value.sig = TARGET_SIGNAL_TRAP;
2600 /* If an error happens while handling the event, propagate GDB's
2601 knowledge of the executing state to the frontend/user running
2603 old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
2605 if (ecs->ws.kind == TARGET_WAITKIND_SYSCALL_ENTRY
2606 || ecs->ws.kind == TARGET_WAITKIND_SYSCALL_RETURN)
2607 ecs->ws.value.syscall_number = UNKNOWN_SYSCALL;
2609 /* Now figure out what to do with the result of the result. */
2610 handle_inferior_event (ecs);
2612 /* No error, don't finish the state yet. */
2613 discard_cleanups (old_chain);
2615 if (!ecs->wait_some_more)
2619 do_cleanups (old_cleanups);
2622 /* Asynchronous version of wait_for_inferior. It is called by the
2623 event loop whenever a change of state is detected on the file
2624 descriptor corresponding to the target. It can be called more than
2625 once to complete a single execution command. In such cases we need
2626 to keep the state in a global variable ECSS. If it is the last time
2627 that this function is called for a single execution command, then
2628 report to the user that the inferior has stopped, and do the
2629 necessary cleanups. */
2632 fetch_inferior_event (void *client_data)
2634 struct execution_control_state ecss;
2635 struct execution_control_state *ecs = &ecss;
2636 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
2637 struct cleanup *ts_old_chain;
2638 int was_sync = sync_execution;
2640 memset (ecs, 0, sizeof (*ecs));
2642 /* We'll update this if & when we switch to a new thread. */
2643 previous_inferior_ptid = inferior_ptid;
2645 /* We're handling a live event, so make sure we're doing live
2646 debugging. If we're looking at traceframes while the target is
2647 running, we're going to need to get back to that mode after
2648 handling the event. */
2651 make_cleanup_restore_current_traceframe ();
2652 set_current_traceframe (-1);
2656 /* In non-stop mode, the user/frontend should not notice a thread
2657 switch due to internal events. Make sure we reverse to the
2658 user selected thread and frame after handling the event and
2659 running any breakpoint commands. */
2660 make_cleanup_restore_current_thread ();
2662 /* We have to invalidate the registers BEFORE calling target_wait
2663 because they can be loaded from the target while in target_wait.
2664 This makes remote debugging a bit more efficient for those
2665 targets that provide critical registers as part of their normal
2666 status mechanism. */
2668 overlay_cache_invalid = 1;
2669 registers_changed ();
2671 if (deprecated_target_wait_hook)
2673 deprecated_target_wait_hook (waiton_ptid, &ecs->ws, TARGET_WNOHANG);
2675 ecs->ptid = target_wait (waiton_ptid, &ecs->ws, TARGET_WNOHANG);
2678 print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
2681 && ecs->ws.kind != TARGET_WAITKIND_IGNORE
2682 && ecs->ws.kind != TARGET_WAITKIND_EXITED
2683 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
2684 /* In non-stop mode, each thread is handled individually. Switch
2685 early, so the global state is set correctly for this
2687 context_switch (ecs->ptid);
2689 /* If an error happens while handling the event, propagate GDB's
2690 knowledge of the executing state to the frontend/user running
2693 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
2695 ts_old_chain = make_cleanup (finish_thread_state_cleanup, &ecs->ptid);
2697 /* Now figure out what to do with the result of the result. */
2698 handle_inferior_event (ecs);
2700 if (!ecs->wait_some_more)
2702 struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
2704 delete_step_thread_step_resume_breakpoint ();
2706 /* We may not find an inferior if this was a process exit. */
2707 if (inf == NULL || inf->control.stop_soon == NO_STOP_QUIETLY)
2710 if (target_has_execution
2711 && ecs->ws.kind != TARGET_WAITKIND_EXITED
2712 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
2713 && ecs->event_thread->step_multi
2714 && ecs->event_thread->control.stop_step)
2715 inferior_event_handler (INF_EXEC_CONTINUE, NULL);
2717 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
2720 /* No error, don't finish the thread states yet. */
2721 discard_cleanups (ts_old_chain);
2723 /* Revert thread and frame. */
2724 do_cleanups (old_chain);
2726 /* If the inferior was in sync execution mode, and now isn't,
2727 restore the prompt. */
2728 if (was_sync && !sync_execution)
2729 display_gdb_prompt (0);
2732 /* Record the frame and location we're currently stepping through. */
2734 set_step_info (struct frame_info *frame, struct symtab_and_line sal)
2736 struct thread_info *tp = inferior_thread ();
2738 tp->control.step_frame_id = get_frame_id (frame);
2739 tp->control.step_stack_frame_id = get_stack_frame_id (frame);
2741 tp->current_symtab = sal.symtab;
2742 tp->current_line = sal.line;
2745 /* Clear context switchable stepping state. */
2748 init_thread_stepping_state (struct thread_info *tss)
2750 tss->stepping_over_breakpoint = 0;
2751 tss->step_after_step_resume_breakpoint = 0;
2752 tss->stepping_through_solib_after_catch = 0;
2753 tss->stepping_through_solib_catchpoints = NULL;
2756 /* Return the cached copy of the last pid/waitstatus returned by
2757 target_wait()/deprecated_target_wait_hook(). The data is actually
2758 cached by handle_inferior_event(), which gets called immediately
2759 after target_wait()/deprecated_target_wait_hook(). */
2762 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
2764 *ptidp = target_last_wait_ptid;
2765 *status = target_last_waitstatus;
2769 nullify_last_target_wait_ptid (void)
2771 target_last_wait_ptid = minus_one_ptid;
2774 /* Switch thread contexts. */
2777 context_switch (ptid_t ptid)
2781 fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ",
2782 target_pid_to_str (inferior_ptid));
2783 fprintf_unfiltered (gdb_stdlog, "to %s\n",
2784 target_pid_to_str (ptid));
2787 switch_to_thread (ptid);
2791 adjust_pc_after_break (struct execution_control_state *ecs)
2793 struct regcache *regcache;
2794 struct gdbarch *gdbarch;
2795 struct address_space *aspace;
2796 CORE_ADDR breakpoint_pc;
2798 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2799 we aren't, just return.
2801 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2802 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2803 implemented by software breakpoints should be handled through the normal
2806 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2807 different signals (SIGILL or SIGEMT for instance), but it is less
2808 clear where the PC is pointing afterwards. It may not match
2809 gdbarch_decr_pc_after_break. I don't know any specific target that
2810 generates these signals at breakpoints (the code has been in GDB since at
2811 least 1992) so I can not guess how to handle them here.
2813 In earlier versions of GDB, a target with
2814 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2815 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2816 target with both of these set in GDB history, and it seems unlikely to be
2817 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2819 if (ecs->ws.kind != TARGET_WAITKIND_STOPPED)
2822 if (ecs->ws.value.sig != TARGET_SIGNAL_TRAP)
2825 /* In reverse execution, when a breakpoint is hit, the instruction
2826 under it has already been de-executed. The reported PC always
2827 points at the breakpoint address, so adjusting it further would
2828 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2831 B1 0x08000000 : INSN1
2832 B2 0x08000001 : INSN2
2834 PC -> 0x08000003 : INSN4
2836 Say you're stopped at 0x08000003 as above. Reverse continuing
2837 from that point should hit B2 as below. Reading the PC when the
2838 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2839 been de-executed already.
2841 B1 0x08000000 : INSN1
2842 B2 PC -> 0x08000001 : INSN2
2846 We can't apply the same logic as for forward execution, because
2847 we would wrongly adjust the PC to 0x08000000, since there's a
2848 breakpoint at PC - 1. We'd then report a hit on B1, although
2849 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2851 if (execution_direction == EXEC_REVERSE)
2854 /* If this target does not decrement the PC after breakpoints, then
2855 we have nothing to do. */
2856 regcache = get_thread_regcache (ecs->ptid);
2857 gdbarch = get_regcache_arch (regcache);
2858 if (gdbarch_decr_pc_after_break (gdbarch) == 0)
2861 aspace = get_regcache_aspace (regcache);
2863 /* Find the location where (if we've hit a breakpoint) the
2864 breakpoint would be. */
2865 breakpoint_pc = regcache_read_pc (regcache)
2866 - gdbarch_decr_pc_after_break (gdbarch);
2868 /* Check whether there actually is a software breakpoint inserted at
2871 If in non-stop mode, a race condition is possible where we've
2872 removed a breakpoint, but stop events for that breakpoint were
2873 already queued and arrive later. To suppress those spurious
2874 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
2875 and retire them after a number of stop events are reported. */
2876 if (software_breakpoint_inserted_here_p (aspace, breakpoint_pc)
2877 || (non_stop && moribund_breakpoint_here_p (aspace, breakpoint_pc)))
2879 struct cleanup *old_cleanups = NULL;
2882 old_cleanups = record_gdb_operation_disable_set ();
2884 /* When using hardware single-step, a SIGTRAP is reported for both
2885 a completed single-step and a software breakpoint. Need to
2886 differentiate between the two, as the latter needs adjusting
2887 but the former does not.
2889 The SIGTRAP can be due to a completed hardware single-step only if
2890 - we didn't insert software single-step breakpoints
2891 - the thread to be examined is still the current thread
2892 - this thread is currently being stepped
2894 If any of these events did not occur, we must have stopped due
2895 to hitting a software breakpoint, and have to back up to the
2898 As a special case, we could have hardware single-stepped a
2899 software breakpoint. In this case (prev_pc == breakpoint_pc),
2900 we also need to back up to the breakpoint address. */
2902 if (singlestep_breakpoints_inserted_p
2903 || !ptid_equal (ecs->ptid, inferior_ptid)
2904 || !currently_stepping (ecs->event_thread)
2905 || ecs->event_thread->prev_pc == breakpoint_pc)
2906 regcache_write_pc (regcache, breakpoint_pc);
2909 do_cleanups (old_cleanups);
2914 init_infwait_state (void)
2916 waiton_ptid = pid_to_ptid (-1);
2917 infwait_state = infwait_normal_state;
2921 error_is_running (void)
2923 error (_("Cannot execute this command while "
2924 "the selected thread is running."));
2928 ensure_not_running (void)
2930 if (is_running (inferior_ptid))
2931 error_is_running ();
2935 stepped_in_from (struct frame_info *frame, struct frame_id step_frame_id)
2937 for (frame = get_prev_frame (frame);
2939 frame = get_prev_frame (frame))
2941 if (frame_id_eq (get_frame_id (frame), step_frame_id))
2943 if (get_frame_type (frame) != INLINE_FRAME)
2950 /* Auxiliary function that handles syscall entry/return events.
2951 It returns 1 if the inferior should keep going (and GDB
2952 should ignore the event), or 0 if the event deserves to be
2956 handle_syscall_event (struct execution_control_state *ecs)
2958 struct regcache *regcache;
2959 struct gdbarch *gdbarch;
2962 if (!ptid_equal (ecs->ptid, inferior_ptid))
2963 context_switch (ecs->ptid);
2965 regcache = get_thread_regcache (ecs->ptid);
2966 gdbarch = get_regcache_arch (regcache);
2967 syscall_number = gdbarch_get_syscall_number (gdbarch, ecs->ptid);
2968 stop_pc = regcache_read_pc (regcache);
2970 target_last_waitstatus.value.syscall_number = syscall_number;
2972 if (catch_syscall_enabled () > 0
2973 && catching_syscall_number (syscall_number) > 0)
2976 fprintf_unfiltered (gdb_stdlog, "infrun: syscall number = '%d'\n",
2979 ecs->event_thread->control.stop_bpstat
2980 = bpstat_stop_status (get_regcache_aspace (regcache),
2981 stop_pc, ecs->ptid);
2983 = !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat);
2985 if (!ecs->random_signal)
2987 /* Catchpoint hit. */
2988 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_TRAP;
2993 /* If no catchpoint triggered for this, then keep going. */
2994 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
2999 /* Given an execution control state that has been freshly filled in
3000 by an event from the inferior, figure out what it means and take
3001 appropriate action. */
3004 handle_inferior_event (struct execution_control_state *ecs)
3006 struct frame_info *frame;
3007 struct gdbarch *gdbarch;
3008 int sw_single_step_trap_p = 0;
3009 int stopped_by_watchpoint;
3010 int stepped_after_stopped_by_watchpoint = 0;
3011 struct symtab_and_line stop_pc_sal;
3012 enum stop_kind stop_soon;
3014 if (ecs->ws.kind == TARGET_WAITKIND_IGNORE)
3016 /* We had an event in the inferior, but we are not interested in
3017 handling it at this level. The lower layers have already
3018 done what needs to be done, if anything.
3020 One of the possible circumstances for this is when the
3021 inferior produces output for the console. The inferior has
3022 not stopped, and we are ignoring the event. Another possible
3023 circumstance is any event which the lower level knows will be
3024 reported multiple times without an intervening resume. */
3026 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n");
3027 prepare_to_wait (ecs);
3031 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
3032 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
3034 struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
3037 stop_soon = inf->control.stop_soon;
3040 stop_soon = NO_STOP_QUIETLY;
3042 /* Cache the last pid/waitstatus. */
3043 target_last_wait_ptid = ecs->ptid;
3044 target_last_waitstatus = ecs->ws;
3046 /* Always clear state belonging to the previous time we stopped. */
3047 stop_stack_dummy = STOP_NONE;
3049 /* If it's a new process, add it to the thread database. */
3051 ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid)
3052 && !ptid_equal (ecs->ptid, minus_one_ptid)
3053 && !in_thread_list (ecs->ptid));
3055 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
3056 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event)
3057 add_thread (ecs->ptid);
3059 ecs->event_thread = find_thread_ptid (ecs->ptid);
3061 /* Dependent on valid ECS->EVENT_THREAD. */
3062 adjust_pc_after_break (ecs);
3064 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3065 reinit_frame_cache ();
3067 breakpoint_retire_moribund ();
3069 /* First, distinguish signals caused by the debugger from signals
3070 that have to do with the program's own actions. Note that
3071 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3072 on the operating system version. Here we detect when a SIGILL or
3073 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3074 something similar for SIGSEGV, since a SIGSEGV will be generated
3075 when we're trying to execute a breakpoint instruction on a
3076 non-executable stack. This happens for call dummy breakpoints
3077 for architectures like SPARC that place call dummies on the
3079 if (ecs->ws.kind == TARGET_WAITKIND_STOPPED
3080 && (ecs->ws.value.sig == TARGET_SIGNAL_ILL
3081 || ecs->ws.value.sig == TARGET_SIGNAL_SEGV
3082 || ecs->ws.value.sig == TARGET_SIGNAL_EMT))
3084 struct regcache *regcache = get_thread_regcache (ecs->ptid);
3086 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache),
3087 regcache_read_pc (regcache)))
3090 fprintf_unfiltered (gdb_stdlog,
3091 "infrun: Treating signal as SIGTRAP\n");
3092 ecs->ws.value.sig = TARGET_SIGNAL_TRAP;
3096 /* Mark the non-executing threads accordingly. In all-stop, all
3097 threads of all processes are stopped when we get any event
3098 reported. In non-stop mode, only the event thread stops. If
3099 we're handling a process exit in non-stop mode, there's nothing
3100 to do, as threads of the dead process are gone, and threads of
3101 any other process were left running. */
3103 set_executing (minus_one_ptid, 0);
3104 else if (ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
3105 && ecs->ws.kind != TARGET_WAITKIND_EXITED)
3106 set_executing (inferior_ptid, 0);
3108 switch (infwait_state)
3110 case infwait_thread_hop_state:
3112 fprintf_unfiltered (gdb_stdlog, "infrun: infwait_thread_hop_state\n");
3115 case infwait_normal_state:
3117 fprintf_unfiltered (gdb_stdlog, "infrun: infwait_normal_state\n");
3120 case infwait_step_watch_state:
3122 fprintf_unfiltered (gdb_stdlog,
3123 "infrun: infwait_step_watch_state\n");
3125 stepped_after_stopped_by_watchpoint = 1;
3128 case infwait_nonstep_watch_state:
3130 fprintf_unfiltered (gdb_stdlog,
3131 "infrun: infwait_nonstep_watch_state\n");
3132 insert_breakpoints ();
3134 /* FIXME-maybe: is this cleaner than setting a flag? Does it
3135 handle things like signals arriving and other things happening
3136 in combination correctly? */
3137 stepped_after_stopped_by_watchpoint = 1;
3141 internal_error (__FILE__, __LINE__, _("bad switch"));
3144 infwait_state = infwait_normal_state;
3145 waiton_ptid = pid_to_ptid (-1);
3147 switch (ecs->ws.kind)
3149 case TARGET_WAITKIND_LOADED:
3151 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n");
3152 /* Ignore gracefully during startup of the inferior, as it might
3153 be the shell which has just loaded some objects, otherwise
3154 add the symbols for the newly loaded objects. Also ignore at
3155 the beginning of an attach or remote session; we will query
3156 the full list of libraries once the connection is
3158 if (stop_soon == NO_STOP_QUIETLY)
3160 /* Check for any newly added shared libraries if we're
3161 supposed to be adding them automatically. Switch
3162 terminal for any messages produced by
3163 breakpoint_re_set. */
3164 target_terminal_ours_for_output ();
3165 /* NOTE: cagney/2003-11-25: Make certain that the target
3166 stack's section table is kept up-to-date. Architectures,
3167 (e.g., PPC64), use the section table to perform
3168 operations such as address => section name and hence
3169 require the table to contain all sections (including
3170 those found in shared libraries). */
3172 SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
3174 solib_add (NULL, 0, ¤t_target, auto_solib_add);
3176 target_terminal_inferior ();
3178 /* If requested, stop when the dynamic linker notifies
3179 gdb of events. This allows the user to get control
3180 and place breakpoints in initializer routines for
3181 dynamically loaded objects (among other things). */
3182 if (stop_on_solib_events)
3184 /* Make sure we print "Stopped due to solib-event" in
3186 stop_print_frame = 1;
3188 stop_stepping (ecs);
3192 /* NOTE drow/2007-05-11: This might be a good place to check
3193 for "catch load". */
3196 /* If we are skipping through a shell, or through shared library
3197 loading that we aren't interested in, resume the program. If
3198 we're running the program normally, also resume. But stop if
3199 we're attaching or setting up a remote connection. */
3200 if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY)
3202 /* Loading of shared libraries might have changed breakpoint
3203 addresses. Make sure new breakpoints are inserted. */
3204 if (stop_soon == NO_STOP_QUIETLY
3205 && !breakpoints_always_inserted_mode ())
3206 insert_breakpoints ();
3207 resume (0, TARGET_SIGNAL_0);
3208 prepare_to_wait (ecs);
3214 case TARGET_WAITKIND_SPURIOUS:
3216 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3217 resume (0, TARGET_SIGNAL_0);
3218 prepare_to_wait (ecs);
3221 case TARGET_WAITKIND_EXITED:
3223 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXITED\n");
3224 inferior_ptid = ecs->ptid;
3225 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs->ptid)));
3226 set_current_program_space (current_inferior ()->pspace);
3227 handle_vfork_child_exec_or_exit (0);
3228 target_terminal_ours (); /* Must do this before mourn anyway. */
3229 print_exited_reason (ecs->ws.value.integer);
3231 /* Record the exit code in the convenience variable $_exitcode, so
3232 that the user can inspect this again later. */
3233 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3234 (LONGEST) ecs->ws.value.integer);
3235 gdb_flush (gdb_stdout);
3236 target_mourn_inferior ();
3237 singlestep_breakpoints_inserted_p = 0;
3238 cancel_single_step_breakpoints ();
3239 stop_print_frame = 0;
3240 stop_stepping (ecs);
3243 case TARGET_WAITKIND_SIGNALLED:
3245 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SIGNALLED\n");
3246 inferior_ptid = ecs->ptid;
3247 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs->ptid)));
3248 set_current_program_space (current_inferior ()->pspace);
3249 handle_vfork_child_exec_or_exit (0);
3250 stop_print_frame = 0;
3251 target_terminal_ours (); /* Must do this before mourn anyway. */
3253 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
3254 reach here unless the inferior is dead. However, for years
3255 target_kill() was called here, which hints that fatal signals aren't
3256 really fatal on some systems. If that's true, then some changes
3258 target_mourn_inferior ();
3260 print_signal_exited_reason (ecs->ws.value.sig);
3261 singlestep_breakpoints_inserted_p = 0;
3262 cancel_single_step_breakpoints ();
3263 stop_stepping (ecs);
3266 /* The following are the only cases in which we keep going;
3267 the above cases end in a continue or goto. */
3268 case TARGET_WAITKIND_FORKED:
3269 case TARGET_WAITKIND_VFORKED:
3271 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
3273 if (!ptid_equal (ecs->ptid, inferior_ptid))
3275 context_switch (ecs->ptid);
3276 reinit_frame_cache ();
3279 /* Immediately detach breakpoints from the child before there's
3280 any chance of letting the user delete breakpoints from the
3281 breakpoint lists. If we don't do this early, it's easy to
3282 leave left over traps in the child, vis: "break foo; catch
3283 fork; c; <fork>; del; c; <child calls foo>". We only follow
3284 the fork on the last `continue', and by that time the
3285 breakpoint at "foo" is long gone from the breakpoint table.
3286 If we vforked, then we don't need to unpatch here, since both
3287 parent and child are sharing the same memory pages; we'll
3288 need to unpatch at follow/detach time instead to be certain
3289 that new breakpoints added between catchpoint hit time and
3290 vfork follow are detached. */
3291 if (ecs->ws.kind != TARGET_WAITKIND_VFORKED)
3293 int child_pid = ptid_get_pid (ecs->ws.value.related_pid);
3295 /* This won't actually modify the breakpoint list, but will
3296 physically remove the breakpoints from the child. */
3297 detach_breakpoints (child_pid);
3300 if (singlestep_breakpoints_inserted_p)
3302 /* Pull the single step breakpoints out of the target. */
3303 remove_single_step_breakpoints ();
3304 singlestep_breakpoints_inserted_p = 0;
3307 /* In case the event is caught by a catchpoint, remember that
3308 the event is to be followed at the next resume of the thread,
3309 and not immediately. */
3310 ecs->event_thread->pending_follow = ecs->ws;
3312 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3314 ecs->event_thread->control.stop_bpstat
3315 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3316 stop_pc, ecs->ptid);
3318 /* Note that we're interested in knowing the bpstat actually
3319 causes a stop, not just if it may explain the signal.
3320 Software watchpoints, for example, always appear in the
3323 = !bpstat_causes_stop (ecs->event_thread->control.stop_bpstat);
3325 /* If no catchpoint triggered for this, then keep going. */
3326 if (ecs->random_signal)
3332 = (follow_fork_mode_string == follow_fork_mode_child);
3334 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
3336 should_resume = follow_fork ();
3339 child = ecs->ws.value.related_pid;
3341 /* In non-stop mode, also resume the other branch. */
3342 if (non_stop && !detach_fork)
3345 switch_to_thread (parent);
3347 switch_to_thread (child);
3349 ecs->event_thread = inferior_thread ();
3350 ecs->ptid = inferior_ptid;
3355 switch_to_thread (child);
3357 switch_to_thread (parent);
3359 ecs->event_thread = inferior_thread ();
3360 ecs->ptid = inferior_ptid;
3365 stop_stepping (ecs);
3368 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_TRAP;
3369 goto process_event_stop_test;
3371 case TARGET_WAITKIND_VFORK_DONE:
3372 /* Done with the shared memory region. Re-insert breakpoints in
3373 the parent, and keep going. */
3376 fprintf_unfiltered (gdb_stdlog,
3377 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3379 if (!ptid_equal (ecs->ptid, inferior_ptid))
3380 context_switch (ecs->ptid);
3382 current_inferior ()->waiting_for_vfork_done = 0;
3383 current_inferior ()->pspace->breakpoints_not_allowed = 0;
3384 /* This also takes care of reinserting breakpoints in the
3385 previously locked inferior. */
3389 case TARGET_WAITKIND_EXECD:
3391 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n");
3393 if (!ptid_equal (ecs->ptid, inferior_ptid))
3395 context_switch (ecs->ptid);
3396 reinit_frame_cache ();
3399 singlestep_breakpoints_inserted_p = 0;
3400 cancel_single_step_breakpoints ();
3402 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3404 /* Do whatever is necessary to the parent branch of the vfork. */
3405 handle_vfork_child_exec_or_exit (1);
3407 /* This causes the eventpoints and symbol table to be reset.
3408 Must do this now, before trying to determine whether to
3410 follow_exec (inferior_ptid, ecs->ws.value.execd_pathname);
3412 ecs->event_thread->control.stop_bpstat
3413 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3414 stop_pc, ecs->ptid);
3416 = !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat);
3418 /* Note that this may be referenced from inside
3419 bpstat_stop_status above, through inferior_has_execd. */
3420 xfree (ecs->ws.value.execd_pathname);
3421 ecs->ws.value.execd_pathname = NULL;
3423 /* If no catchpoint triggered for this, then keep going. */
3424 if (ecs->random_signal)
3426 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
3430 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_TRAP;
3431 goto process_event_stop_test;
3433 /* Be careful not to try to gather much state about a thread
3434 that's in a syscall. It's frequently a losing proposition. */
3435 case TARGET_WAITKIND_SYSCALL_ENTRY:
3437 fprintf_unfiltered (gdb_stdlog,
3438 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3439 /* Getting the current syscall number. */
3440 if (handle_syscall_event (ecs) != 0)
3442 goto process_event_stop_test;
3444 /* Before examining the threads further, step this thread to
3445 get it entirely out of the syscall. (We get notice of the
3446 event when the thread is just on the verge of exiting a
3447 syscall. Stepping one instruction seems to get it back
3449 case TARGET_WAITKIND_SYSCALL_RETURN:
3451 fprintf_unfiltered (gdb_stdlog,
3452 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3453 if (handle_syscall_event (ecs) != 0)
3455 goto process_event_stop_test;
3457 case TARGET_WAITKIND_STOPPED:
3459 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n");
3460 ecs->event_thread->suspend.stop_signal = ecs->ws.value.sig;
3463 case TARGET_WAITKIND_NO_HISTORY:
3464 /* Reverse execution: target ran out of history info. */
3465 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3466 print_no_history_reason ();
3467 stop_stepping (ecs);
3471 if (ecs->new_thread_event)
3474 /* Non-stop assumes that the target handles adding new threads
3475 to the thread list. */
3476 internal_error (__FILE__, __LINE__,
3477 "targets should add new threads to the thread "
3478 "list themselves in non-stop mode.");
3480 /* We may want to consider not doing a resume here in order to
3481 give the user a chance to play with the new thread. It might
3482 be good to make that a user-settable option. */
3484 /* At this point, all threads are stopped (happens automatically
3485 in either the OS or the native code). Therefore we need to
3486 continue all threads in order to make progress. */
3488 if (!ptid_equal (ecs->ptid, inferior_ptid))
3489 context_switch (ecs->ptid);
3490 target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
3491 prepare_to_wait (ecs);
3495 if (ecs->ws.kind == TARGET_WAITKIND_STOPPED)
3497 /* Do we need to clean up the state of a thread that has
3498 completed a displaced single-step? (Doing so usually affects
3499 the PC, so do it here, before we set stop_pc.) */
3500 displaced_step_fixup (ecs->ptid,
3501 ecs->event_thread->suspend.stop_signal);
3503 /* If we either finished a single-step or hit a breakpoint, but
3504 the user wanted this thread to be stopped, pretend we got a
3505 SIG0 (generic unsignaled stop). */
3507 if (ecs->event_thread->stop_requested
3508 && ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP)
3509 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
3512 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
3516 struct regcache *regcache = get_thread_regcache (ecs->ptid);
3517 struct gdbarch *gdbarch = get_regcache_arch (regcache);
3518 struct cleanup *old_chain = save_inferior_ptid ();
3520 inferior_ptid = ecs->ptid;
3522 fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = %s\n",
3523 paddress (gdbarch, stop_pc));
3524 if (target_stopped_by_watchpoint ())
3528 fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n");
3530 if (target_stopped_data_address (¤t_target, &addr))
3531 fprintf_unfiltered (gdb_stdlog,
3532 "infrun: stopped data address = %s\n",
3533 paddress (gdbarch, addr));
3535 fprintf_unfiltered (gdb_stdlog,
3536 "infrun: (no data address available)\n");
3539 do_cleanups (old_chain);
3542 if (stepping_past_singlestep_breakpoint)
3544 gdb_assert (singlestep_breakpoints_inserted_p);
3545 gdb_assert (ptid_equal (singlestep_ptid, ecs->ptid));
3546 gdb_assert (!ptid_equal (singlestep_ptid, saved_singlestep_ptid));
3548 stepping_past_singlestep_breakpoint = 0;
3550 /* We've either finished single-stepping past the single-step
3551 breakpoint, or stopped for some other reason. It would be nice if
3552 we could tell, but we can't reliably. */
3553 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP)
3556 fprintf_unfiltered (gdb_stdlog,
3557 "infrun: stepping_past_"
3558 "singlestep_breakpoint\n");
3559 /* Pull the single step breakpoints out of the target. */
3560 remove_single_step_breakpoints ();
3561 singlestep_breakpoints_inserted_p = 0;
3563 ecs->random_signal = 0;
3564 ecs->event_thread->control.trap_expected = 0;
3566 context_switch (saved_singlestep_ptid);
3567 if (deprecated_context_hook)
3568 deprecated_context_hook (pid_to_thread_id (ecs->ptid));
3570 resume (1, TARGET_SIGNAL_0);
3571 prepare_to_wait (ecs);
3576 if (!ptid_equal (deferred_step_ptid, null_ptid))
3578 /* In non-stop mode, there's never a deferred_step_ptid set. */
3579 gdb_assert (!non_stop);
3581 /* If we stopped for some other reason than single-stepping, ignore
3582 the fact that we were supposed to switch back. */
3583 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP)
3586 fprintf_unfiltered (gdb_stdlog,
3587 "infrun: handling deferred step\n");
3589 /* Pull the single step breakpoints out of the target. */
3590 if (singlestep_breakpoints_inserted_p)
3592 remove_single_step_breakpoints ();
3593 singlestep_breakpoints_inserted_p = 0;
3596 /* Note: We do not call context_switch at this point, as the
3597 context is already set up for stepping the original thread. */
3598 switch_to_thread (deferred_step_ptid);
3599 deferred_step_ptid = null_ptid;
3600 /* Suppress spurious "Switching to ..." message. */
3601 previous_inferior_ptid = inferior_ptid;
3603 resume (1, TARGET_SIGNAL_0);
3604 prepare_to_wait (ecs);
3608 deferred_step_ptid = null_ptid;
3611 /* See if a thread hit a thread-specific breakpoint that was meant for
3612 another thread. If so, then step that thread past the breakpoint,
3615 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP)
3617 int thread_hop_needed = 0;
3618 struct address_space *aspace =
3619 get_regcache_aspace (get_thread_regcache (ecs->ptid));
3621 /* Check if a regular breakpoint has been hit before checking
3622 for a potential single step breakpoint. Otherwise, GDB will
3623 not see this breakpoint hit when stepping onto breakpoints. */
3624 if (regular_breakpoint_inserted_here_p (aspace, stop_pc))
3626 ecs->random_signal = 0;
3627 if (!breakpoint_thread_match (aspace, stop_pc, ecs->ptid))
3628 thread_hop_needed = 1;
3630 else if (singlestep_breakpoints_inserted_p)
3632 /* We have not context switched yet, so this should be true
3633 no matter which thread hit the singlestep breakpoint. */
3634 gdb_assert (ptid_equal (inferior_ptid, singlestep_ptid));
3636 fprintf_unfiltered (gdb_stdlog, "infrun: software single step "
3638 target_pid_to_str (ecs->ptid));
3640 ecs->random_signal = 0;
3641 /* The call to in_thread_list is necessary because PTIDs sometimes
3642 change when we go from single-threaded to multi-threaded. If
3643 the singlestep_ptid is still in the list, assume that it is
3644 really different from ecs->ptid. */
3645 if (!ptid_equal (singlestep_ptid, ecs->ptid)
3646 && in_thread_list (singlestep_ptid))
3648 /* If the PC of the thread we were trying to single-step
3649 has changed, discard this event (which we were going
3650 to ignore anyway), and pretend we saw that thread
3651 trap. This prevents us continuously moving the
3652 single-step breakpoint forward, one instruction at a
3653 time. If the PC has changed, then the thread we were
3654 trying to single-step has trapped or been signalled,
3655 but the event has not been reported to GDB yet.
3657 There might be some cases where this loses signal
3658 information, if a signal has arrived at exactly the
3659 same time that the PC changed, but this is the best
3660 we can do with the information available. Perhaps we
3661 should arrange to report all events for all threads
3662 when they stop, or to re-poll the remote looking for
3663 this particular thread (i.e. temporarily enable
3666 CORE_ADDR new_singlestep_pc
3667 = regcache_read_pc (get_thread_regcache (singlestep_ptid));
3669 if (new_singlestep_pc != singlestep_pc)
3671 enum target_signal stop_signal;
3674 fprintf_unfiltered (gdb_stdlog, "infrun: unexpected thread,"
3675 " but expected thread advanced also\n");
3677 /* The current context still belongs to
3678 singlestep_ptid. Don't swap here, since that's
3679 the context we want to use. Just fudge our
3680 state and continue. */
3681 stop_signal = ecs->event_thread->suspend.stop_signal;
3682 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
3683 ecs->ptid = singlestep_ptid;
3684 ecs->event_thread = find_thread_ptid (ecs->ptid);
3685 ecs->event_thread->suspend.stop_signal = stop_signal;
3686 stop_pc = new_singlestep_pc;
3691 fprintf_unfiltered (gdb_stdlog,
3692 "infrun: unexpected thread\n");
3694 thread_hop_needed = 1;
3695 stepping_past_singlestep_breakpoint = 1;
3696 saved_singlestep_ptid = singlestep_ptid;
3701 if (thread_hop_needed)
3703 struct regcache *thread_regcache;
3704 int remove_status = 0;
3707 fprintf_unfiltered (gdb_stdlog, "infrun: thread_hop_needed\n");
3709 /* Switch context before touching inferior memory, the
3710 previous thread may have exited. */
3711 if (!ptid_equal (inferior_ptid, ecs->ptid))
3712 context_switch (ecs->ptid);
3714 /* Saw a breakpoint, but it was hit by the wrong thread.
3717 if (singlestep_breakpoints_inserted_p)
3719 /* Pull the single step breakpoints out of the target. */
3720 remove_single_step_breakpoints ();
3721 singlestep_breakpoints_inserted_p = 0;
3724 /* If the arch can displace step, don't remove the
3726 thread_regcache = get_thread_regcache (ecs->ptid);
3727 if (!use_displaced_stepping (get_regcache_arch (thread_regcache)))
3728 remove_status = remove_breakpoints ();
3730 /* Did we fail to remove breakpoints? If so, try
3731 to set the PC past the bp. (There's at least
3732 one situation in which we can fail to remove
3733 the bp's: On HP-UX's that use ttrace, we can't
3734 change the address space of a vforking child
3735 process until the child exits (well, okay, not
3736 then either :-) or execs. */
3737 if (remove_status != 0)
3738 error (_("Cannot step over breakpoint hit in wrong thread"));
3743 /* Only need to require the next event from this
3744 thread in all-stop mode. */
3745 waiton_ptid = ecs->ptid;
3746 infwait_state = infwait_thread_hop_state;
3749 ecs->event_thread->stepping_over_breakpoint = 1;
3754 else if (singlestep_breakpoints_inserted_p)
3756 sw_single_step_trap_p = 1;
3757 ecs->random_signal = 0;
3761 ecs->random_signal = 1;
3763 /* See if something interesting happened to the non-current thread. If
3764 so, then switch to that thread. */
3765 if (!ptid_equal (ecs->ptid, inferior_ptid))
3768 fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n");
3770 context_switch (ecs->ptid);
3772 if (deprecated_context_hook)
3773 deprecated_context_hook (pid_to_thread_id (ecs->ptid));
3776 /* At this point, get hold of the now-current thread's frame. */
3777 frame = get_current_frame ();
3778 gdbarch = get_frame_arch (frame);
3780 if (singlestep_breakpoints_inserted_p)
3782 /* Pull the single step breakpoints out of the target. */
3783 remove_single_step_breakpoints ();
3784 singlestep_breakpoints_inserted_p = 0;
3787 if (stepped_after_stopped_by_watchpoint)
3788 stopped_by_watchpoint = 0;
3790 stopped_by_watchpoint = watchpoints_triggered (&ecs->ws);
3792 /* If necessary, step over this watchpoint. We'll be back to display
3794 if (stopped_by_watchpoint
3795 && (target_have_steppable_watchpoint
3796 || gdbarch_have_nonsteppable_watchpoint (gdbarch)))
3798 /* At this point, we are stopped at an instruction which has
3799 attempted to write to a piece of memory under control of
3800 a watchpoint. The instruction hasn't actually executed
3801 yet. If we were to evaluate the watchpoint expression
3802 now, we would get the old value, and therefore no change
3803 would seem to have occurred.
3805 In order to make watchpoints work `right', we really need
3806 to complete the memory write, and then evaluate the
3807 watchpoint expression. We do this by single-stepping the
3810 It may not be necessary to disable the watchpoint to stop over
3811 it. For example, the PA can (with some kernel cooperation)
3812 single step over a watchpoint without disabling the watchpoint.
3814 It is far more common to need to disable a watchpoint to step
3815 the inferior over it. If we have non-steppable watchpoints,
3816 we must disable the current watchpoint; it's simplest to
3817 disable all watchpoints and breakpoints. */
3820 if (!target_have_steppable_watchpoint)
3821 remove_breakpoints ();
3823 hw_step = maybe_software_singlestep (gdbarch, stop_pc);
3824 target_resume (ecs->ptid, hw_step, TARGET_SIGNAL_0);
3825 waiton_ptid = ecs->ptid;
3826 if (target_have_steppable_watchpoint)
3827 infwait_state = infwait_step_watch_state;
3829 infwait_state = infwait_nonstep_watch_state;
3830 prepare_to_wait (ecs);
3834 ecs->stop_func_start = 0;
3835 ecs->stop_func_end = 0;
3836 ecs->stop_func_name = 0;
3837 /* Don't care about return value; stop_func_start and stop_func_name
3838 will both be 0 if it doesn't work. */
3839 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
3840 &ecs->stop_func_start, &ecs->stop_func_end);
3841 ecs->stop_func_start
3842 += gdbarch_deprecated_function_start_offset (gdbarch);
3843 ecs->event_thread->stepping_over_breakpoint = 0;
3844 bpstat_clear (&ecs->event_thread->control.stop_bpstat);
3845 ecs->event_thread->control.stop_step = 0;
3846 stop_print_frame = 1;
3847 ecs->random_signal = 0;
3848 stopped_by_random_signal = 0;
3850 /* Hide inlined functions starting here, unless we just performed stepi or
3851 nexti. After stepi and nexti, always show the innermost frame (not any
3852 inline function call sites). */
3853 if (ecs->event_thread->control.step_range_end != 1)
3854 skip_inline_frames (ecs->ptid);
3856 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP
3857 && ecs->event_thread->control.trap_expected
3858 && gdbarch_single_step_through_delay_p (gdbarch)
3859 && currently_stepping (ecs->event_thread))
3861 /* We're trying to step off a breakpoint. Turns out that we're
3862 also on an instruction that needs to be stepped multiple
3863 times before it's been fully executing. E.g., architectures
3864 with a delay slot. It needs to be stepped twice, once for
3865 the instruction and once for the delay slot. */
3866 int step_through_delay
3867 = gdbarch_single_step_through_delay (gdbarch, frame);
3869 if (debug_infrun && step_through_delay)
3870 fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n");
3871 if (ecs->event_thread->control.step_range_end == 0
3872 && step_through_delay)
3874 /* The user issued a continue when stopped at a breakpoint.
3875 Set up for another trap and get out of here. */
3876 ecs->event_thread->stepping_over_breakpoint = 1;
3880 else if (step_through_delay)
3882 /* The user issued a step when stopped at a breakpoint.
3883 Maybe we should stop, maybe we should not - the delay
3884 slot *might* correspond to a line of source. In any
3885 case, don't decide that here, just set
3886 ecs->stepping_over_breakpoint, making sure we
3887 single-step again before breakpoints are re-inserted. */
3888 ecs->event_thread->stepping_over_breakpoint = 1;
3892 /* Look at the cause of the stop, and decide what to do.
3893 The alternatives are:
3894 1) stop_stepping and return; to really stop and return to the debugger,
3895 2) keep_going and return to start up again
3896 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
3897 3) set ecs->random_signal to 1, and the decision between 1 and 2
3898 will be made according to the signal handling tables. */
3900 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP
3901 || stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_NO_SIGSTOP
3902 || stop_soon == STOP_QUIETLY_REMOTE)
3904 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP
3908 fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n");
3909 stop_print_frame = 0;
3910 stop_stepping (ecs);
3914 /* This is originated from start_remote(), start_inferior() and
3915 shared libraries hook functions. */
3916 if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE)
3919 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
3920 stop_stepping (ecs);
3924 /* This originates from attach_command(). We need to overwrite
3925 the stop_signal here, because some kernels don't ignore a
3926 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
3927 See more comments in inferior.h. On the other hand, if we
3928 get a non-SIGSTOP, report it to the user - assume the backend
3929 will handle the SIGSTOP if it should show up later.
3931 Also consider that the attach is complete when we see a
3932 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
3933 target extended-remote report it instead of a SIGSTOP
3934 (e.g. gdbserver). We already rely on SIGTRAP being our
3935 signal, so this is no exception.
3937 Also consider that the attach is complete when we see a
3938 TARGET_SIGNAL_0. In non-stop mode, GDB will explicitly tell
3939 the target to stop all threads of the inferior, in case the
3940 low level attach operation doesn't stop them implicitly. If
3941 they weren't stopped implicitly, then the stub will report a
3942 TARGET_SIGNAL_0, meaning: stopped for no particular reason
3943 other than GDB's request. */
3944 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
3945 && (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_STOP
3946 || ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP
3947 || ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_0))
3949 stop_stepping (ecs);
3950 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
3954 /* See if there is a breakpoint at the current PC. */
3955 ecs->event_thread->control.stop_bpstat
3956 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3957 stop_pc, ecs->ptid);
3959 /* Following in case break condition called a
3961 stop_print_frame = 1;
3963 /* This is where we handle "moribund" watchpoints. Unlike
3964 software breakpoints traps, hardware watchpoint traps are
3965 always distinguishable from random traps. If no high-level
3966 watchpoint is associated with the reported stop data address
3967 anymore, then the bpstat does not explain the signal ---
3968 simply make sure to ignore it if `stopped_by_watchpoint' is
3972 && ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP
3973 && !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat)
3974 && stopped_by_watchpoint)
3975 fprintf_unfiltered (gdb_stdlog,
3976 "infrun: no user watchpoint explains "
3977 "watchpoint SIGTRAP, ignoring\n");
3979 /* NOTE: cagney/2003-03-29: These two checks for a random signal
3980 at one stage in the past included checks for an inferior
3981 function call's call dummy's return breakpoint. The original
3982 comment, that went with the test, read:
3984 ``End of a stack dummy. Some systems (e.g. Sony news) give
3985 another signal besides SIGTRAP, so check here as well as
3988 If someone ever tries to get call dummys on a
3989 non-executable stack to work (where the target would stop
3990 with something like a SIGSEGV), then those tests might need
3991 to be re-instated. Given, however, that the tests were only
3992 enabled when momentary breakpoints were not being used, I
3993 suspect that it won't be the case.
3995 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
3996 be necessary for call dummies on a non-executable stack on
3999 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP)
4001 = !(bpstat_explains_signal (ecs->event_thread->control.stop_bpstat)
4002 || stopped_by_watchpoint
4003 || ecs->event_thread->control.trap_expected
4004 || (ecs->event_thread->control.step_range_end
4005 && (ecs->event_thread->control.step_resume_breakpoint
4009 ecs->random_signal = !bpstat_explains_signal
4010 (ecs->event_thread->control.stop_bpstat);
4011 if (!ecs->random_signal)
4012 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_TRAP;
4016 /* When we reach this point, we've pretty much decided
4017 that the reason for stopping must've been a random
4018 (unexpected) signal. */
4021 ecs->random_signal = 1;
4023 process_event_stop_test:
4025 /* Re-fetch current thread's frame in case we did a
4026 "goto process_event_stop_test" above. */
4027 frame = get_current_frame ();
4028 gdbarch = get_frame_arch (frame);
4030 /* For the program's own signals, act according to
4031 the signal handling tables. */
4033 if (ecs->random_signal)
4035 /* Signal not for debugging purposes. */
4037 struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
4040 fprintf_unfiltered (gdb_stdlog, "infrun: random signal %d\n",
4041 ecs->event_thread->suspend.stop_signal);
4043 stopped_by_random_signal = 1;
4045 if (signal_print[ecs->event_thread->suspend.stop_signal])
4048 target_terminal_ours_for_output ();
4049 print_signal_received_reason
4050 (ecs->event_thread->suspend.stop_signal);
4052 /* Always stop on signals if we're either just gaining control
4053 of the program, or the user explicitly requested this thread
4054 to remain stopped. */
4055 if (stop_soon != NO_STOP_QUIETLY
4056 || ecs->event_thread->stop_requested
4058 && signal_stop_state (ecs->event_thread->suspend.stop_signal)))
4060 stop_stepping (ecs);
4063 /* If not going to stop, give terminal back
4064 if we took it away. */
4066 target_terminal_inferior ();
4068 /* Clear the signal if it should not be passed. */
4069 if (signal_program[ecs->event_thread->suspend.stop_signal] == 0)
4070 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
4072 if (ecs->event_thread->prev_pc == stop_pc
4073 && ecs->event_thread->control.trap_expected
4074 && ecs->event_thread->control.step_resume_breakpoint == NULL)
4076 /* We were just starting a new sequence, attempting to
4077 single-step off of a breakpoint and expecting a SIGTRAP.
4078 Instead this signal arrives. This signal will take us out
4079 of the stepping range so GDB needs to remember to, when
4080 the signal handler returns, resume stepping off that
4082 /* To simplify things, "continue" is forced to use the same
4083 code paths as single-step - set a breakpoint at the
4084 signal return address and then, once hit, step off that
4087 fprintf_unfiltered (gdb_stdlog,
4088 "infrun: signal arrived while stepping over "
4091 insert_step_resume_breakpoint_at_frame (frame);
4092 ecs->event_thread->step_after_step_resume_breakpoint = 1;
4097 if (ecs->event_thread->control.step_range_end != 0
4098 && ecs->event_thread->suspend.stop_signal != TARGET_SIGNAL_0
4099 && (ecs->event_thread->control.step_range_start <= stop_pc
4100 && stop_pc < ecs->event_thread->control.step_range_end)
4101 && frame_id_eq (get_stack_frame_id (frame),
4102 ecs->event_thread->control.step_stack_frame_id)
4103 && ecs->event_thread->control.step_resume_breakpoint == NULL)
4105 /* The inferior is about to take a signal that will take it
4106 out of the single step range. Set a breakpoint at the
4107 current PC (which is presumably where the signal handler
4108 will eventually return) and then allow the inferior to
4111 Note that this is only needed for a signal delivered
4112 while in the single-step range. Nested signals aren't a
4113 problem as they eventually all return. */
4115 fprintf_unfiltered (gdb_stdlog,
4116 "infrun: signal may take us out of "
4117 "single-step range\n");
4119 insert_step_resume_breakpoint_at_frame (frame);
4124 /* Note: step_resume_breakpoint may be non-NULL. This occures
4125 when either there's a nested signal, or when there's a
4126 pending signal enabled just as the signal handler returns
4127 (leaving the inferior at the step-resume-breakpoint without
4128 actually executing it). Either way continue until the
4129 breakpoint is really hit. */
4134 /* Handle cases caused by hitting a breakpoint. */
4136 CORE_ADDR jmp_buf_pc;
4137 struct bpstat_what what;
4139 what = bpstat_what (ecs->event_thread->control.stop_bpstat);
4141 if (what.call_dummy)
4143 stop_stack_dummy = what.call_dummy;
4146 /* If we hit an internal event that triggers symbol changes, the
4147 current frame will be invalidated within bpstat_what (e.g., if
4148 we hit an internal solib event). Re-fetch it. */
4149 frame = get_current_frame ();
4150 gdbarch = get_frame_arch (frame);
4152 switch (what.main_action)
4154 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
4155 /* If we hit the breakpoint at longjmp while stepping, we
4156 install a momentary breakpoint at the target of the
4160 fprintf_unfiltered (gdb_stdlog,
4161 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4163 ecs->event_thread->stepping_over_breakpoint = 1;
4165 if (what.is_longjmp)
4167 if (!gdbarch_get_longjmp_target_p (gdbarch)
4168 || !gdbarch_get_longjmp_target (gdbarch,
4169 frame, &jmp_buf_pc))
4172 fprintf_unfiltered (gdb_stdlog,
4173 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4174 "(!gdbarch_get_longjmp_target)\n");
4179 /* We're going to replace the current step-resume breakpoint
4180 with a longjmp-resume breakpoint. */
4181 delete_step_resume_breakpoint (ecs->event_thread);
4183 /* Insert a breakpoint at resume address. */
4184 insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc);
4188 struct symbol *func = get_frame_function (frame);
4191 check_exception_resume (ecs, frame, func);
4196 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
4198 fprintf_unfiltered (gdb_stdlog,
4199 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4201 if (what.is_longjmp)
4203 gdb_assert (ecs->event_thread->control.step_resume_breakpoint
4205 delete_step_resume_breakpoint (ecs->event_thread);
4209 /* There are several cases to consider.
4211 1. The initiating frame no longer exists. In this case
4212 we must stop, because the exception has gone too far.
4214 2. The initiating frame exists, and is the same as the
4215 current frame. We stop, because the exception has been
4218 3. The initiating frame exists and is different from
4219 the current frame. This means the exception has been
4220 caught beneath the initiating frame, so keep going. */
4221 struct frame_info *init_frame
4222 = frame_find_by_id (ecs->event_thread->initiating_frame);
4224 gdb_assert (ecs->event_thread->control.exception_resume_breakpoint
4226 delete_exception_resume_breakpoint (ecs->event_thread);
4230 struct frame_id current_id
4231 = get_frame_id (get_current_frame ());
4232 if (frame_id_eq (current_id,
4233 ecs->event_thread->initiating_frame))
4235 /* Case 2. Fall through. */
4245 /* For Cases 1 and 2, remove the step-resume breakpoint,
4247 delete_step_resume_breakpoint (ecs->event_thread);
4250 ecs->event_thread->control.stop_step = 1;
4251 print_end_stepping_range_reason ();
4252 stop_stepping (ecs);
4255 case BPSTAT_WHAT_SINGLE:
4257 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
4258 ecs->event_thread->stepping_over_breakpoint = 1;
4259 /* Still need to check other stuff, at least the case
4260 where we are stepping and step out of the right range. */
4263 case BPSTAT_WHAT_STOP_NOISY:
4265 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4266 stop_print_frame = 1;
4268 /* We are about to nuke the step_resume_breakpointt via the
4269 cleanup chain, so no need to worry about it here. */
4271 stop_stepping (ecs);
4274 case BPSTAT_WHAT_STOP_SILENT:
4276 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4277 stop_print_frame = 0;
4279 /* We are about to nuke the step_resume_breakpoin via the
4280 cleanup chain, so no need to worry about it here. */
4282 stop_stepping (ecs);
4285 case BPSTAT_WHAT_STEP_RESUME:
4287 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4289 delete_step_resume_breakpoint (ecs->event_thread);
4290 if (ecs->event_thread->step_after_step_resume_breakpoint)
4292 /* Back when the step-resume breakpoint was inserted, we
4293 were trying to single-step off a breakpoint. Go back
4295 ecs->event_thread->step_after_step_resume_breakpoint = 0;
4296 ecs->event_thread->stepping_over_breakpoint = 1;
4300 if (stop_pc == ecs->stop_func_start
4301 && execution_direction == EXEC_REVERSE)
4303 /* We are stepping over a function call in reverse, and
4304 just hit the step-resume breakpoint at the start
4305 address of the function. Go back to single-stepping,
4306 which should take us back to the function call. */
4307 ecs->event_thread->stepping_over_breakpoint = 1;
4313 case BPSTAT_WHAT_KEEP_CHECKING:
4318 /* We come here if we hit a breakpoint but should not
4319 stop for it. Possibly we also were stepping
4320 and should stop for that. So fall through and
4321 test for stepping. But, if not stepping,
4324 /* In all-stop mode, if we're currently stepping but have stopped in
4325 some other thread, we need to switch back to the stepped thread. */
4328 struct thread_info *tp;
4330 tp = iterate_over_threads (currently_stepping_or_nexting_callback,
4334 /* However, if the current thread is blocked on some internal
4335 breakpoint, and we simply need to step over that breakpoint
4336 to get it going again, do that first. */
4337 if ((ecs->event_thread->control.trap_expected
4338 && ecs->event_thread->suspend.stop_signal != TARGET_SIGNAL_TRAP)
4339 || ecs->event_thread->stepping_over_breakpoint)
4345 /* If the stepping thread exited, then don't try to switch
4346 back and resume it, which could fail in several different
4347 ways depending on the target. Instead, just keep going.
4349 We can find a stepping dead thread in the thread list in
4352 - The target supports thread exit events, and when the
4353 target tries to delete the thread from the thread list,
4354 inferior_ptid pointed at the exiting thread. In such
4355 case, calling delete_thread does not really remove the
4356 thread from the list; instead, the thread is left listed,
4357 with 'exited' state.
4359 - The target's debug interface does not support thread
4360 exit events, and so we have no idea whatsoever if the
4361 previously stepping thread is still alive. For that
4362 reason, we need to synchronously query the target
4364 if (is_exited (tp->ptid)
4365 || !target_thread_alive (tp->ptid))
4368 fprintf_unfiltered (gdb_stdlog,
4369 "infrun: not switching back to "
4370 "stepped thread, it has vanished\n");
4372 delete_thread (tp->ptid);
4377 /* Otherwise, we no longer expect a trap in the current thread.
4378 Clear the trap_expected flag before switching back -- this is
4379 what keep_going would do as well, if we called it. */
4380 ecs->event_thread->control.trap_expected = 0;
4383 fprintf_unfiltered (gdb_stdlog,
4384 "infrun: switching back to stepped thread\n");
4386 ecs->event_thread = tp;
4387 ecs->ptid = tp->ptid;
4388 context_switch (ecs->ptid);
4394 /* Are we stepping to get the inferior out of the dynamic linker's
4395 hook (and possibly the dld itself) after catching a shlib
4397 if (ecs->event_thread->stepping_through_solib_after_catch)
4399 #if defined(SOLIB_ADD)
4400 /* Have we reached our destination? If not, keep going. */
4401 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs->ptid), stop_pc))
4404 fprintf_unfiltered (gdb_stdlog,
4405 "infrun: stepping in dynamic linker\n");
4406 ecs->event_thread->stepping_over_breakpoint = 1;
4412 fprintf_unfiltered (gdb_stdlog, "infrun: step past dynamic linker\n");
4413 /* Else, stop and report the catchpoint(s) whose triggering
4414 caused us to begin stepping. */
4415 ecs->event_thread->stepping_through_solib_after_catch = 0;
4416 bpstat_clear (&ecs->event_thread->control.stop_bpstat);
4417 ecs->event_thread->control.stop_bpstat
4418 = bpstat_copy (ecs->event_thread->stepping_through_solib_catchpoints);
4419 bpstat_clear (&ecs->event_thread->stepping_through_solib_catchpoints);
4420 stop_print_frame = 1;
4421 stop_stepping (ecs);
4425 if (ecs->event_thread->control.step_resume_breakpoint)
4428 fprintf_unfiltered (gdb_stdlog,
4429 "infrun: step-resume breakpoint is inserted\n");
4431 /* Having a step-resume breakpoint overrides anything
4432 else having to do with stepping commands until
4433 that breakpoint is reached. */
4438 if (ecs->event_thread->control.step_range_end == 0)
4441 fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n");
4442 /* Likewise if we aren't even stepping. */
4447 /* Re-fetch current thread's frame in case the code above caused
4448 the frame cache to be re-initialized, making our FRAME variable
4449 a dangling pointer. */
4450 frame = get_current_frame ();
4451 gdbarch = get_frame_arch (frame);
4453 /* If stepping through a line, keep going if still within it.
4455 Note that step_range_end is the address of the first instruction
4456 beyond the step range, and NOT the address of the last instruction
4459 Note also that during reverse execution, we may be stepping
4460 through a function epilogue and therefore must detect when
4461 the current-frame changes in the middle of a line. */
4463 if (stop_pc >= ecs->event_thread->control.step_range_start
4464 && stop_pc < ecs->event_thread->control.step_range_end
4465 && (execution_direction != EXEC_REVERSE
4466 || frame_id_eq (get_frame_id (frame),
4467 ecs->event_thread->control.step_frame_id)))
4471 (gdb_stdlog, "infrun: stepping inside range [%s-%s]\n",
4472 paddress (gdbarch, ecs->event_thread->control.step_range_start),
4473 paddress (gdbarch, ecs->event_thread->control.step_range_end));
4475 /* When stepping backward, stop at beginning of line range
4476 (unless it's the function entry point, in which case
4477 keep going back to the call point). */
4478 if (stop_pc == ecs->event_thread->control.step_range_start
4479 && stop_pc != ecs->stop_func_start
4480 && execution_direction == EXEC_REVERSE)
4482 ecs->event_thread->control.stop_step = 1;
4483 print_end_stepping_range_reason ();
4484 stop_stepping (ecs);
4492 /* We stepped out of the stepping range. */
4494 /* If we are stepping at the source level and entered the runtime
4495 loader dynamic symbol resolution code...
4497 EXEC_FORWARD: we keep on single stepping until we exit the run
4498 time loader code and reach the callee's address.
4500 EXEC_REVERSE: we've already executed the callee (backward), and
4501 the runtime loader code is handled just like any other
4502 undebuggable function call. Now we need only keep stepping
4503 backward through the trampoline code, and that's handled further
4504 down, so there is nothing for us to do here. */
4506 if (execution_direction != EXEC_REVERSE
4507 && ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
4508 && in_solib_dynsym_resolve_code (stop_pc))
4510 CORE_ADDR pc_after_resolver =
4511 gdbarch_skip_solib_resolver (gdbarch, stop_pc);
4514 fprintf_unfiltered (gdb_stdlog,
4515 "infrun: stepped into dynsym resolve code\n");
4517 if (pc_after_resolver)
4519 /* Set up a step-resume breakpoint at the address
4520 indicated by SKIP_SOLIB_RESOLVER. */
4521 struct symtab_and_line sr_sal;
4524 sr_sal.pc = pc_after_resolver;
4525 sr_sal.pspace = get_frame_program_space (frame);
4527 insert_step_resume_breakpoint_at_sal (gdbarch,
4528 sr_sal, null_frame_id);
4535 if (ecs->event_thread->control.step_range_end != 1
4536 && (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
4537 || ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
4538 && get_frame_type (frame) == SIGTRAMP_FRAME)
4541 fprintf_unfiltered (gdb_stdlog,
4542 "infrun: stepped into signal trampoline\n");
4543 /* The inferior, while doing a "step" or "next", has ended up in
4544 a signal trampoline (either by a signal being delivered or by
4545 the signal handler returning). Just single-step until the
4546 inferior leaves the trampoline (either by calling the handler
4552 /* Check for subroutine calls. The check for the current frame
4553 equalling the step ID is not necessary - the check of the
4554 previous frame's ID is sufficient - but it is a common case and
4555 cheaper than checking the previous frame's ID.
4557 NOTE: frame_id_eq will never report two invalid frame IDs as
4558 being equal, so to get into this block, both the current and
4559 previous frame must have valid frame IDs. */
4560 /* The outer_frame_id check is a heuristic to detect stepping
4561 through startup code. If we step over an instruction which
4562 sets the stack pointer from an invalid value to a valid value,
4563 we may detect that as a subroutine call from the mythical
4564 "outermost" function. This could be fixed by marking
4565 outermost frames as !stack_p,code_p,special_p. Then the
4566 initial outermost frame, before sp was valid, would
4567 have code_addr == &_start. See the comment in frame_id_eq
4569 if (!frame_id_eq (get_stack_frame_id (frame),
4570 ecs->event_thread->control.step_stack_frame_id)
4571 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4572 ecs->event_thread->control.step_stack_frame_id)
4573 && (!frame_id_eq (ecs->event_thread->control.step_stack_frame_id,
4575 || step_start_function != find_pc_function (stop_pc))))
4577 CORE_ADDR real_stop_pc;
4580 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n");
4582 if ((ecs->event_thread->control.step_over_calls == STEP_OVER_NONE)
4583 || ((ecs->event_thread->control.step_range_end == 1)
4584 && in_prologue (gdbarch, ecs->event_thread->prev_pc,
4585 ecs->stop_func_start)))
4587 /* I presume that step_over_calls is only 0 when we're
4588 supposed to be stepping at the assembly language level
4589 ("stepi"). Just stop. */
4590 /* Also, maybe we just did a "nexti" inside a prolog, so we
4591 thought it was a subroutine call but it was not. Stop as
4593 /* And this works the same backward as frontward. MVS */
4594 ecs->event_thread->control.stop_step = 1;
4595 print_end_stepping_range_reason ();
4596 stop_stepping (ecs);
4600 /* Reverse stepping through solib trampolines. */
4602 if (execution_direction == EXEC_REVERSE
4603 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE
4604 && (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
4605 || (ecs->stop_func_start == 0
4606 && in_solib_dynsym_resolve_code (stop_pc))))
4608 /* Any solib trampoline code can be handled in reverse
4609 by simply continuing to single-step. We have already
4610 executed the solib function (backwards), and a few
4611 steps will take us back through the trampoline to the
4617 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
4619 /* We're doing a "next".
4621 Normal (forward) execution: set a breakpoint at the
4622 callee's return address (the address at which the caller
4625 Reverse (backward) execution. set the step-resume
4626 breakpoint at the start of the function that we just
4627 stepped into (backwards), and continue to there. When we
4628 get there, we'll need to single-step back to the caller. */
4630 if (execution_direction == EXEC_REVERSE)
4632 struct symtab_and_line sr_sal;
4634 /* Normal function call return (static or dynamic). */
4636 sr_sal.pc = ecs->stop_func_start;
4637 sr_sal.pspace = get_frame_program_space (frame);
4638 insert_step_resume_breakpoint_at_sal (gdbarch,
4639 sr_sal, null_frame_id);
4642 insert_step_resume_breakpoint_at_caller (frame);
4648 /* If we are in a function call trampoline (a stub between the
4649 calling routine and the real function), locate the real
4650 function. That's what tells us (a) whether we want to step
4651 into it at all, and (b) what prologue we want to run to the
4652 end of, if we do step into it. */
4653 real_stop_pc = skip_language_trampoline (frame, stop_pc);
4654 if (real_stop_pc == 0)
4655 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
4656 if (real_stop_pc != 0)
4657 ecs->stop_func_start = real_stop_pc;
4659 if (real_stop_pc != 0 && in_solib_dynsym_resolve_code (real_stop_pc))
4661 struct symtab_and_line sr_sal;
4664 sr_sal.pc = ecs->stop_func_start;
4665 sr_sal.pspace = get_frame_program_space (frame);
4667 insert_step_resume_breakpoint_at_sal (gdbarch,
4668 sr_sal, null_frame_id);
4673 /* If we have line number information for the function we are
4674 thinking of stepping into, step into it.
4676 If there are several symtabs at that PC (e.g. with include
4677 files), just want to know whether *any* of them have line
4678 numbers. find_pc_line handles this. */
4680 struct symtab_and_line tmp_sal;
4682 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
4683 if (tmp_sal.line != 0)
4685 if (execution_direction == EXEC_REVERSE)
4686 handle_step_into_function_backward (gdbarch, ecs);
4688 handle_step_into_function (gdbarch, ecs);
4693 /* If we have no line number and the step-stop-if-no-debug is
4694 set, we stop the step so that the user has a chance to switch
4695 in assembly mode. */
4696 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
4697 && step_stop_if_no_debug)
4699 ecs->event_thread->control.stop_step = 1;
4700 print_end_stepping_range_reason ();
4701 stop_stepping (ecs);
4705 if (execution_direction == EXEC_REVERSE)
4707 /* Set a breakpoint at callee's start address.
4708 From there we can step once and be back in the caller. */
4709 struct symtab_and_line sr_sal;
4712 sr_sal.pc = ecs->stop_func_start;
4713 sr_sal.pspace = get_frame_program_space (frame);
4714 insert_step_resume_breakpoint_at_sal (gdbarch,
4715 sr_sal, null_frame_id);
4718 /* Set a breakpoint at callee's return address (the address
4719 at which the caller will resume). */
4720 insert_step_resume_breakpoint_at_caller (frame);
4726 /* Reverse stepping through solib trampolines. */
4728 if (execution_direction == EXEC_REVERSE
4729 && ecs->event_thread->control.step_over_calls != STEP_OVER_NONE)
4731 if (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
4732 || (ecs->stop_func_start == 0
4733 && in_solib_dynsym_resolve_code (stop_pc)))
4735 /* Any solib trampoline code can be handled in reverse
4736 by simply continuing to single-step. We have already
4737 executed the solib function (backwards), and a few
4738 steps will take us back through the trampoline to the
4743 else if (in_solib_dynsym_resolve_code (stop_pc))
4745 /* Stepped backward into the solib dynsym resolver.
4746 Set a breakpoint at its start and continue, then
4747 one more step will take us out. */
4748 struct symtab_and_line sr_sal;
4751 sr_sal.pc = ecs->stop_func_start;
4752 sr_sal.pspace = get_frame_program_space (frame);
4753 insert_step_resume_breakpoint_at_sal (gdbarch,
4754 sr_sal, null_frame_id);
4760 /* If we're in the return path from a shared library trampoline,
4761 we want to proceed through the trampoline when stepping. */
4762 if (gdbarch_in_solib_return_trampoline (gdbarch,
4763 stop_pc, ecs->stop_func_name))
4765 /* Determine where this trampoline returns. */
4766 CORE_ADDR real_stop_pc;
4768 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
4771 fprintf_unfiltered (gdb_stdlog,
4772 "infrun: stepped into solib return tramp\n");
4774 /* Only proceed through if we know where it's going. */
4777 /* And put the step-breakpoint there and go until there. */
4778 struct symtab_and_line sr_sal;
4780 init_sal (&sr_sal); /* initialize to zeroes */
4781 sr_sal.pc = real_stop_pc;
4782 sr_sal.section = find_pc_overlay (sr_sal.pc);
4783 sr_sal.pspace = get_frame_program_space (frame);
4785 /* Do not specify what the fp should be when we stop since
4786 on some machines the prologue is where the new fp value
4788 insert_step_resume_breakpoint_at_sal (gdbarch,
4789 sr_sal, null_frame_id);
4791 /* Restart without fiddling with the step ranges or
4798 stop_pc_sal = find_pc_line (stop_pc, 0);
4800 /* NOTE: tausq/2004-05-24: This if block used to be done before all
4801 the trampoline processing logic, however, there are some trampolines
4802 that have no names, so we should do trampoline handling first. */
4803 if (ecs->event_thread->control.step_over_calls == STEP_OVER_UNDEBUGGABLE
4804 && ecs->stop_func_name == NULL
4805 && stop_pc_sal.line == 0)
4808 fprintf_unfiltered (gdb_stdlog,
4809 "infrun: stepped into undebuggable function\n");
4811 /* The inferior just stepped into, or returned to, an
4812 undebuggable function (where there is no debugging information
4813 and no line number corresponding to the address where the
4814 inferior stopped). Since we want to skip this kind of code,
4815 we keep going until the inferior returns from this
4816 function - unless the user has asked us not to (via
4817 set step-mode) or we no longer know how to get back
4818 to the call site. */
4819 if (step_stop_if_no_debug
4820 || !frame_id_p (frame_unwind_caller_id (frame)))
4822 /* If we have no line number and the step-stop-if-no-debug
4823 is set, we stop the step so that the user has a chance to
4824 switch in assembly mode. */
4825 ecs->event_thread->control.stop_step = 1;
4826 print_end_stepping_range_reason ();
4827 stop_stepping (ecs);
4832 /* Set a breakpoint at callee's return address (the address
4833 at which the caller will resume). */
4834 insert_step_resume_breakpoint_at_caller (frame);
4840 if (ecs->event_thread->control.step_range_end == 1)
4842 /* It is stepi or nexti. We always want to stop stepping after
4845 fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
4846 ecs->event_thread->control.stop_step = 1;
4847 print_end_stepping_range_reason ();
4848 stop_stepping (ecs);
4852 if (stop_pc_sal.line == 0)
4854 /* We have no line number information. That means to stop
4855 stepping (does this always happen right after one instruction,
4856 when we do "s" in a function with no line numbers,
4857 or can this happen as a result of a return or longjmp?). */
4859 fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n");
4860 ecs->event_thread->control.stop_step = 1;
4861 print_end_stepping_range_reason ();
4862 stop_stepping (ecs);
4866 /* Look for "calls" to inlined functions, part one. If the inline
4867 frame machinery detected some skipped call sites, we have entered
4868 a new inline function. */
4870 if (frame_id_eq (get_frame_id (get_current_frame ()),
4871 ecs->event_thread->control.step_frame_id)
4872 && inline_skipped_frames (ecs->ptid))
4874 struct symtab_and_line call_sal;
4877 fprintf_unfiltered (gdb_stdlog,
4878 "infrun: stepped into inlined function\n");
4880 find_frame_sal (get_current_frame (), &call_sal);
4882 if (ecs->event_thread->control.step_over_calls != STEP_OVER_ALL)
4884 /* For "step", we're going to stop. But if the call site
4885 for this inlined function is on the same source line as
4886 we were previously stepping, go down into the function
4887 first. Otherwise stop at the call site. */
4889 if (call_sal.line == ecs->event_thread->current_line
4890 && call_sal.symtab == ecs->event_thread->current_symtab)
4891 step_into_inline_frame (ecs->ptid);
4893 ecs->event_thread->control.stop_step = 1;
4894 print_end_stepping_range_reason ();
4895 stop_stepping (ecs);
4900 /* For "next", we should stop at the call site if it is on a
4901 different source line. Otherwise continue through the
4902 inlined function. */
4903 if (call_sal.line == ecs->event_thread->current_line
4904 && call_sal.symtab == ecs->event_thread->current_symtab)
4908 ecs->event_thread->control.stop_step = 1;
4909 print_end_stepping_range_reason ();
4910 stop_stepping (ecs);
4916 /* Look for "calls" to inlined functions, part two. If we are still
4917 in the same real function we were stepping through, but we have
4918 to go further up to find the exact frame ID, we are stepping
4919 through a more inlined call beyond its call site. */
4921 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
4922 && !frame_id_eq (get_frame_id (get_current_frame ()),
4923 ecs->event_thread->control.step_frame_id)
4924 && stepped_in_from (get_current_frame (),
4925 ecs->event_thread->control.step_frame_id))
4928 fprintf_unfiltered (gdb_stdlog,
4929 "infrun: stepping through inlined function\n");
4931 if (ecs->event_thread->control.step_over_calls == STEP_OVER_ALL)
4935 ecs->event_thread->control.stop_step = 1;
4936 print_end_stepping_range_reason ();
4937 stop_stepping (ecs);
4942 if ((stop_pc == stop_pc_sal.pc)
4943 && (ecs->event_thread->current_line != stop_pc_sal.line
4944 || ecs->event_thread->current_symtab != stop_pc_sal.symtab))
4946 /* We are at the start of a different line. So stop. Note that
4947 we don't stop if we step into the middle of a different line.
4948 That is said to make things like for (;;) statements work
4951 fprintf_unfiltered (gdb_stdlog,
4952 "infrun: stepped to a different line\n");
4953 ecs->event_thread->control.stop_step = 1;
4954 print_end_stepping_range_reason ();
4955 stop_stepping (ecs);
4959 /* We aren't done stepping.
4961 Optimize by setting the stepping range to the line.
4962 (We might not be in the original line, but if we entered a
4963 new line in mid-statement, we continue stepping. This makes
4964 things like for(;;) statements work better.) */
4966 ecs->event_thread->control.step_range_start = stop_pc_sal.pc;
4967 ecs->event_thread->control.step_range_end = stop_pc_sal.end;
4968 set_step_info (frame, stop_pc_sal);
4971 fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n");
4975 /* Is thread TP in the middle of single-stepping? */
4978 currently_stepping (struct thread_info *tp)
4980 return ((tp->control.step_range_end
4981 && tp->control.step_resume_breakpoint == NULL)
4982 || tp->control.trap_expected
4983 || tp->stepping_through_solib_after_catch
4984 || bpstat_should_step ());
4987 /* Returns true if any thread *but* the one passed in "data" is in the
4988 middle of stepping or of handling a "next". */
4991 currently_stepping_or_nexting_callback (struct thread_info *tp, void *data)
4996 return (tp->control.step_range_end
4997 || tp->control.trap_expected
4998 || tp->stepping_through_solib_after_catch);
5001 /* Inferior has stepped into a subroutine call with source code that
5002 we should not step over. Do step to the first line of code in
5006 handle_step_into_function (struct gdbarch *gdbarch,
5007 struct execution_control_state *ecs)
5010 struct symtab_and_line stop_func_sal, sr_sal;
5012 s = find_pc_symtab (stop_pc);
5013 if (s && s->language != language_asm)
5014 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
5015 ecs->stop_func_start);
5017 stop_func_sal = find_pc_line (ecs->stop_func_start, 0);
5018 /* Use the step_resume_break to step until the end of the prologue,
5019 even if that involves jumps (as it seems to on the vax under
5021 /* If the prologue ends in the middle of a source line, continue to
5022 the end of that source line (if it is still within the function).
5023 Otherwise, just go to end of prologue. */
5024 if (stop_func_sal.end
5025 && stop_func_sal.pc != ecs->stop_func_start
5026 && stop_func_sal.end < ecs->stop_func_end)
5027 ecs->stop_func_start = stop_func_sal.end;
5029 /* Architectures which require breakpoint adjustment might not be able
5030 to place a breakpoint at the computed address. If so, the test
5031 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5032 ecs->stop_func_start to an address at which a breakpoint may be
5033 legitimately placed.
5035 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5036 made, GDB will enter an infinite loop when stepping through
5037 optimized code consisting of VLIW instructions which contain
5038 subinstructions corresponding to different source lines. On
5039 FR-V, it's not permitted to place a breakpoint on any but the
5040 first subinstruction of a VLIW instruction. When a breakpoint is
5041 set, GDB will adjust the breakpoint address to the beginning of
5042 the VLIW instruction. Thus, we need to make the corresponding
5043 adjustment here when computing the stop address. */
5045 if (gdbarch_adjust_breakpoint_address_p (gdbarch))
5047 ecs->stop_func_start
5048 = gdbarch_adjust_breakpoint_address (gdbarch,
5049 ecs->stop_func_start);
5052 if (ecs->stop_func_start == stop_pc)
5054 /* We are already there: stop now. */
5055 ecs->event_thread->control.stop_step = 1;
5056 print_end_stepping_range_reason ();
5057 stop_stepping (ecs);
5062 /* Put the step-breakpoint there and go until there. */
5063 init_sal (&sr_sal); /* initialize to zeroes */
5064 sr_sal.pc = ecs->stop_func_start;
5065 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
5066 sr_sal.pspace = get_frame_program_space (get_current_frame ());
5068 /* Do not specify what the fp should be when we stop since on
5069 some machines the prologue is where the new fp value is
5071 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal, null_frame_id);
5073 /* And make sure stepping stops right away then. */
5074 ecs->event_thread->control.step_range_end
5075 = ecs->event_thread->control.step_range_start;
5080 /* Inferior has stepped backward into a subroutine call with source
5081 code that we should not step over. Do step to the beginning of the
5082 last line of code in it. */
5085 handle_step_into_function_backward (struct gdbarch *gdbarch,
5086 struct execution_control_state *ecs)
5089 struct symtab_and_line stop_func_sal;
5091 s = find_pc_symtab (stop_pc);
5092 if (s && s->language != language_asm)
5093 ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
5094 ecs->stop_func_start);
5096 stop_func_sal = find_pc_line (stop_pc, 0);
5098 /* OK, we're just going to keep stepping here. */
5099 if (stop_func_sal.pc == stop_pc)
5101 /* We're there already. Just stop stepping now. */
5102 ecs->event_thread->control.stop_step = 1;
5103 print_end_stepping_range_reason ();
5104 stop_stepping (ecs);
5108 /* Else just reset the step range and keep going.
5109 No step-resume breakpoint, they don't work for
5110 epilogues, which can have multiple entry paths. */
5111 ecs->event_thread->control.step_range_start = stop_func_sal.pc;
5112 ecs->event_thread->control.step_range_end = stop_func_sal.end;
5118 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5119 This is used to both functions and to skip over code. */
5122 insert_step_resume_breakpoint_at_sal (struct gdbarch *gdbarch,
5123 struct symtab_and_line sr_sal,
5124 struct frame_id sr_id)
5126 /* There should never be more than one step-resume or longjmp-resume
5127 breakpoint per thread, so we should never be setting a new
5128 step_resume_breakpoint when one is already active. */
5129 gdb_assert (inferior_thread ()->control.step_resume_breakpoint == NULL);
5132 fprintf_unfiltered (gdb_stdlog,
5133 "infrun: inserting step-resume breakpoint at %s\n",
5134 paddress (gdbarch, sr_sal.pc));
5136 inferior_thread ()->control.step_resume_breakpoint
5137 = set_momentary_breakpoint (gdbarch, sr_sal, sr_id, bp_step_resume);
5140 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
5141 to skip a potential signal handler.
5143 This is called with the interrupted function's frame. The signal
5144 handler, when it returns, will resume the interrupted function at
5148 insert_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
5150 struct symtab_and_line sr_sal;
5151 struct gdbarch *gdbarch;
5153 gdb_assert (return_frame != NULL);
5154 init_sal (&sr_sal); /* initialize to zeros */
5156 gdbarch = get_frame_arch (return_frame);
5157 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch, get_frame_pc (return_frame));
5158 sr_sal.section = find_pc_overlay (sr_sal.pc);
5159 sr_sal.pspace = get_frame_program_space (return_frame);
5161 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal,
5162 get_stack_frame_id (return_frame));
5165 /* Similar to insert_step_resume_breakpoint_at_frame, except
5166 but a breakpoint at the previous frame's PC. This is used to
5167 skip a function after stepping into it (for "next" or if the called
5168 function has no debugging information).
5170 The current function has almost always been reached by single
5171 stepping a call or return instruction. NEXT_FRAME belongs to the
5172 current function, and the breakpoint will be set at the caller's
5175 This is a separate function rather than reusing
5176 insert_step_resume_breakpoint_at_frame in order to avoid
5177 get_prev_frame, which may stop prematurely (see the implementation
5178 of frame_unwind_caller_id for an example). */
5181 insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame)
5183 struct symtab_and_line sr_sal;
5184 struct gdbarch *gdbarch;
5186 /* We shouldn't have gotten here if we don't know where the call site
5188 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame)));
5190 init_sal (&sr_sal); /* initialize to zeros */
5192 gdbarch = frame_unwind_caller_arch (next_frame);
5193 sr_sal.pc = gdbarch_addr_bits_remove (gdbarch,
5194 frame_unwind_caller_pc (next_frame));
5195 sr_sal.section = find_pc_overlay (sr_sal.pc);
5196 sr_sal.pspace = frame_unwind_program_space (next_frame);
5198 insert_step_resume_breakpoint_at_sal (gdbarch, sr_sal,
5199 frame_unwind_caller_id (next_frame));
5202 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5203 new breakpoint at the target of a jmp_buf. The handling of
5204 longjmp-resume uses the same mechanisms used for handling
5205 "step-resume" breakpoints. */
5208 insert_longjmp_resume_breakpoint (struct gdbarch *gdbarch, CORE_ADDR pc)
5210 /* There should never be more than one step-resume or longjmp-resume
5211 breakpoint per thread, so we should never be setting a new
5212 longjmp_resume_breakpoint when one is already active. */
5213 gdb_assert (inferior_thread ()->control.step_resume_breakpoint == NULL);
5216 fprintf_unfiltered (gdb_stdlog,
5217 "infrun: inserting longjmp-resume breakpoint at %s\n",
5218 paddress (gdbarch, pc));
5220 inferior_thread ()->control.step_resume_breakpoint =
5221 set_momentary_breakpoint_at_pc (gdbarch, pc, bp_longjmp_resume);
5224 /* Insert an exception resume breakpoint. TP is the thread throwing
5225 the exception. The block B is the block of the unwinder debug hook
5226 function. FRAME is the frame corresponding to the call to this
5227 function. SYM is the symbol of the function argument holding the
5228 target PC of the exception. */
5231 insert_exception_resume_breakpoint (struct thread_info *tp,
5233 struct frame_info *frame,
5236 struct gdb_exception e;
5238 /* We want to ignore errors here. */
5239 TRY_CATCH (e, RETURN_MASK_ERROR)
5241 struct symbol *vsym;
5242 struct value *value;
5244 struct breakpoint *bp;
5246 vsym = lookup_symbol (SYMBOL_LINKAGE_NAME (sym), b, VAR_DOMAIN, NULL);
5247 value = read_var_value (vsym, frame);
5248 /* If the value was optimized out, revert to the old behavior. */
5249 if (! value_optimized_out (value))
5251 handler = value_as_address (value);
5254 fprintf_unfiltered (gdb_stdlog,
5255 "infrun: exception resume at %lx\n",
5256 (unsigned long) handler);
5258 bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
5259 handler, bp_exception_resume);
5260 bp->thread = tp->num;
5261 inferior_thread ()->control.exception_resume_breakpoint = bp;
5266 /* This is called when an exception has been intercepted. Check to
5267 see whether the exception's destination is of interest, and if so,
5268 set an exception resume breakpoint there. */
5271 check_exception_resume (struct execution_control_state *ecs,
5272 struct frame_info *frame, struct symbol *func)
5274 struct gdb_exception e;
5276 TRY_CATCH (e, RETURN_MASK_ERROR)
5279 struct dict_iterator iter;
5283 /* The exception breakpoint is a thread-specific breakpoint on
5284 the unwinder's debug hook, declared as:
5286 void _Unwind_DebugHook (void *cfa, void *handler);
5288 The CFA argument indicates the frame to which control is
5289 about to be transferred. HANDLER is the destination PC.
5291 We ignore the CFA and set a temporary breakpoint at HANDLER.
5292 This is not extremely efficient but it avoids issues in gdb
5293 with computing the DWARF CFA, and it also works even in weird
5294 cases such as throwing an exception from inside a signal
5297 b = SYMBOL_BLOCK_VALUE (func);
5298 ALL_BLOCK_SYMBOLS (b, iter, sym)
5300 if (!SYMBOL_IS_ARGUMENT (sym))
5307 insert_exception_resume_breakpoint (ecs->event_thread,
5316 stop_stepping (struct execution_control_state *ecs)
5319 fprintf_unfiltered (gdb_stdlog, "infrun: stop_stepping\n");
5321 /* Let callers know we don't want to wait for the inferior anymore. */
5322 ecs->wait_some_more = 0;
5325 /* This function handles various cases where we need to continue
5326 waiting for the inferior. */
5327 /* (Used to be the keep_going: label in the old wait_for_inferior). */
5330 keep_going (struct execution_control_state *ecs)
5332 /* Make sure normal_stop is called if we get a QUIT handled before
5334 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
5336 /* Save the pc before execution, to compare with pc after stop. */
5337 ecs->event_thread->prev_pc
5338 = regcache_read_pc (get_thread_regcache (ecs->ptid));
5340 /* If we did not do break;, it means we should keep running the
5341 inferior and not return to debugger. */
5343 if (ecs->event_thread->control.trap_expected
5344 && ecs->event_thread->suspend.stop_signal != TARGET_SIGNAL_TRAP)
5346 /* We took a signal (which we are supposed to pass through to
5347 the inferior, else we'd not get here) and we haven't yet
5348 gotten our trap. Simply continue. */
5350 discard_cleanups (old_cleanups);
5351 resume (currently_stepping (ecs->event_thread),
5352 ecs->event_thread->suspend.stop_signal);
5356 /* Either the trap was not expected, but we are continuing
5357 anyway (the user asked that this signal be passed to the
5360 The signal was SIGTRAP, e.g. it was our signal, but we
5361 decided we should resume from it.
5363 We're going to run this baby now!
5365 Note that insert_breakpoints won't try to re-insert
5366 already inserted breakpoints. Therefore, we don't
5367 care if breakpoints were already inserted, or not. */
5369 if (ecs->event_thread->stepping_over_breakpoint)
5371 struct regcache *thread_regcache = get_thread_regcache (ecs->ptid);
5373 if (!use_displaced_stepping (get_regcache_arch (thread_regcache)))
5374 /* Since we can't do a displaced step, we have to remove
5375 the breakpoint while we step it. To keep things
5376 simple, we remove them all. */
5377 remove_breakpoints ();
5381 struct gdb_exception e;
5383 /* Stop stepping when inserting breakpoints
5385 TRY_CATCH (e, RETURN_MASK_ERROR)
5387 insert_breakpoints ();
5391 exception_print (gdb_stderr, e);
5392 stop_stepping (ecs);
5397 ecs->event_thread->control.trap_expected
5398 = ecs->event_thread->stepping_over_breakpoint;
5400 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
5401 specifies that such a signal should be delivered to the
5404 Typically, this would occure when a user is debugging a
5405 target monitor on a simulator: the target monitor sets a
5406 breakpoint; the simulator encounters this break-point and
5407 halts the simulation handing control to GDB; GDB, noteing
5408 that the break-point isn't valid, returns control back to the
5409 simulator; the simulator then delivers the hardware
5410 equivalent of a SIGNAL_TRAP to the program being debugged. */
5412 if (ecs->event_thread->suspend.stop_signal == TARGET_SIGNAL_TRAP
5413 && !signal_program[ecs->event_thread->suspend.stop_signal])
5414 ecs->event_thread->suspend.stop_signal = TARGET_SIGNAL_0;
5416 discard_cleanups (old_cleanups);
5417 resume (currently_stepping (ecs->event_thread),
5418 ecs->event_thread->suspend.stop_signal);
5421 prepare_to_wait (ecs);
5424 /* This function normally comes after a resume, before
5425 handle_inferior_event exits. It takes care of any last bits of
5426 housekeeping, and sets the all-important wait_some_more flag. */
5429 prepare_to_wait (struct execution_control_state *ecs)
5432 fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n");
5434 /* This is the old end of the while loop. Let everybody know we
5435 want to wait for the inferior some more and get called again
5437 ecs->wait_some_more = 1;
5440 /* Several print_*_reason functions to print why the inferior has stopped.
5441 We always print something when the inferior exits, or receives a signal.
5442 The rest of the cases are dealt with later on in normal_stop and
5443 print_it_typical. Ideally there should be a call to one of these
5444 print_*_reason functions functions from handle_inferior_event each time
5445 stop_stepping is called. */
5447 /* Print why the inferior has stopped.
5448 We are done with a step/next/si/ni command, print why the inferior has
5449 stopped. For now print nothing. Print a message only if not in the middle
5450 of doing a "step n" operation for n > 1. */
5453 print_end_stepping_range_reason (void)
5455 if ((!inferior_thread ()->step_multi
5456 || !inferior_thread ()->control.stop_step)
5457 && ui_out_is_mi_like_p (uiout))
5458 ui_out_field_string (uiout, "reason",
5459 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE));
5462 /* The inferior was terminated by a signal, print why it stopped. */
5465 print_signal_exited_reason (enum target_signal siggnal)
5467 annotate_signalled ();
5468 if (ui_out_is_mi_like_p (uiout))
5470 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED));
5471 ui_out_text (uiout, "\nProgram terminated with signal ");
5472 annotate_signal_name ();
5473 ui_out_field_string (uiout, "signal-name",
5474 target_signal_to_name (siggnal));
5475 annotate_signal_name_end ();
5476 ui_out_text (uiout, ", ");
5477 annotate_signal_string ();
5478 ui_out_field_string (uiout, "signal-meaning",
5479 target_signal_to_string (siggnal));
5480 annotate_signal_string_end ();
5481 ui_out_text (uiout, ".\n");
5482 ui_out_text (uiout, "The program no longer exists.\n");
5485 /* The inferior program is finished, print why it stopped. */
5488 print_exited_reason (int exitstatus)
5490 annotate_exited (exitstatus);
5493 if (ui_out_is_mi_like_p (uiout))
5494 ui_out_field_string (uiout, "reason",
5495 async_reason_lookup (EXEC_ASYNC_EXITED));
5496 ui_out_text (uiout, "\nProgram exited with code ");
5497 ui_out_field_fmt (uiout, "exit-code", "0%o", (unsigned int) exitstatus);
5498 ui_out_text (uiout, ".\n");
5502 if (ui_out_is_mi_like_p (uiout))
5504 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY));
5505 ui_out_text (uiout, "\nProgram exited normally.\n");
5507 /* Support the --return-child-result option. */
5508 return_child_result_value = exitstatus;
5511 /* Signal received, print why the inferior has stopped. The signal table
5512 tells us to print about it. */
5515 print_signal_received_reason (enum target_signal siggnal)
5519 if (siggnal == TARGET_SIGNAL_0 && !ui_out_is_mi_like_p (uiout))
5521 struct thread_info *t = inferior_thread ();
5523 ui_out_text (uiout, "\n[");
5524 ui_out_field_string (uiout, "thread-name",
5525 target_pid_to_str (t->ptid));
5526 ui_out_field_fmt (uiout, "thread-id", "] #%d", t->num);
5527 ui_out_text (uiout, " stopped");
5531 ui_out_text (uiout, "\nProgram received signal ");
5532 annotate_signal_name ();
5533 if (ui_out_is_mi_like_p (uiout))
5535 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
5536 ui_out_field_string (uiout, "signal-name",
5537 target_signal_to_name (siggnal));
5538 annotate_signal_name_end ();
5539 ui_out_text (uiout, ", ");
5540 annotate_signal_string ();
5541 ui_out_field_string (uiout, "signal-meaning",
5542 target_signal_to_string (siggnal));
5543 annotate_signal_string_end ();
5545 ui_out_text (uiout, ".\n");
5548 /* Reverse execution: target ran out of history info, print why the inferior
5552 print_no_history_reason (void)
5554 ui_out_text (uiout, "\nNo more reverse-execution history.\n");
5557 /* Here to return control to GDB when the inferior stops for real.
5558 Print appropriate messages, remove breakpoints, give terminal our modes.
5560 STOP_PRINT_FRAME nonzero means print the executing frame
5561 (pc, function, args, file, line number and line text).
5562 BREAKPOINTS_FAILED nonzero means stop was due to error
5563 attempting to insert breakpoints. */
5568 struct target_waitstatus last;
5570 struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
5572 get_last_target_status (&last_ptid, &last);
5574 /* If an exception is thrown from this point on, make sure to
5575 propagate GDB's knowledge of the executing state to the
5576 frontend/user running state. A QUIT is an easy exception to see
5577 here, so do this before any filtered output. */
5579 make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
5580 else if (last.kind != TARGET_WAITKIND_SIGNALLED
5581 && last.kind != TARGET_WAITKIND_EXITED)
5582 make_cleanup (finish_thread_state_cleanup, &inferior_ptid);
5584 /* In non-stop mode, we don't want GDB to switch threads behind the
5585 user's back, to avoid races where the user is typing a command to
5586 apply to thread x, but GDB switches to thread y before the user
5587 finishes entering the command. */
5589 /* As with the notification of thread events, we want to delay
5590 notifying the user that we've switched thread context until
5591 the inferior actually stops.
5593 There's no point in saying anything if the inferior has exited.
5594 Note that SIGNALLED here means "exited with a signal", not
5595 "received a signal". */
5597 && !ptid_equal (previous_inferior_ptid, inferior_ptid)
5598 && target_has_execution
5599 && last.kind != TARGET_WAITKIND_SIGNALLED
5600 && last.kind != TARGET_WAITKIND_EXITED)
5602 target_terminal_ours_for_output ();
5603 printf_filtered (_("[Switching to %s]\n"),
5604 target_pid_to_str (inferior_ptid));
5605 annotate_thread_changed ();
5606 previous_inferior_ptid = inferior_ptid;
5609 if (!breakpoints_always_inserted_mode () && target_has_execution)
5611 if (remove_breakpoints ())
5613 target_terminal_ours_for_output ();
5614 printf_filtered (_("Cannot remove breakpoints because "
5615 "program is no longer writable.\nFurther "
5616 "execution is probably impossible.\n"));
5620 /* If an auto-display called a function and that got a signal,
5621 delete that auto-display to avoid an infinite recursion. */
5623 if (stopped_by_random_signal)
5624 disable_current_display ();
5626 /* Don't print a message if in the middle of doing a "step n"
5627 operation for n > 1 */
5628 if (target_has_execution
5629 && last.kind != TARGET_WAITKIND_SIGNALLED
5630 && last.kind != TARGET_WAITKIND_EXITED
5631 && inferior_thread ()->step_multi
5632 && inferior_thread ()->control.stop_step)
5635 target_terminal_ours ();
5637 /* Set the current source location. This will also happen if we
5638 display the frame below, but the current SAL will be incorrect
5639 during a user hook-stop function. */
5640 if (has_stack_frames () && !stop_stack_dummy)
5641 set_current_sal_from_frame (get_current_frame (), 1);
5643 /* Let the user/frontend see the threads as stopped. */
5644 do_cleanups (old_chain);
5646 /* Look up the hook_stop and run it (CLI internally handles problem
5647 of stop_command's pre-hook not existing). */
5649 catch_errors (hook_stop_stub, stop_command,
5650 "Error while running hook_stop:\n", RETURN_MASK_ALL);
5652 if (!has_stack_frames ())
5655 if (last.kind == TARGET_WAITKIND_SIGNALLED
5656 || last.kind == TARGET_WAITKIND_EXITED)
5659 /* Select innermost stack frame - i.e., current frame is frame 0,
5660 and current location is based on that.
5661 Don't do this on return from a stack dummy routine,
5662 or if the program has exited. */
5664 if (!stop_stack_dummy)
5666 select_frame (get_current_frame ());
5668 /* Print current location without a level number, if
5669 we have changed functions or hit a breakpoint.
5670 Print source line if we have one.
5671 bpstat_print() contains the logic deciding in detail
5672 what to print, based on the event(s) that just occurred. */
5674 /* If --batch-silent is enabled then there's no need to print the current
5675 source location, and to try risks causing an error message about
5676 missing source files. */
5677 if (stop_print_frame && !batch_silent)
5681 int do_frame_printing = 1;
5682 struct thread_info *tp = inferior_thread ();
5684 bpstat_ret = bpstat_print (tp->control.stop_bpstat);
5688 /* If we had hit a shared library event breakpoint,
5689 bpstat_print would print out this message. If we hit
5690 an OS-level shared library event, do the same
5692 if (last.kind == TARGET_WAITKIND_LOADED)
5694 printf_filtered (_("Stopped due to shared library event\n"));
5695 source_flag = SRC_LINE; /* something bogus */
5696 do_frame_printing = 0;
5700 /* FIXME: cagney/2002-12-01: Given that a frame ID does
5701 (or should) carry around the function and does (or
5702 should) use that when doing a frame comparison. */
5703 if (tp->control.stop_step
5704 && frame_id_eq (tp->control.step_frame_id,
5705 get_frame_id (get_current_frame ()))
5706 && step_start_function == find_pc_function (stop_pc))
5707 source_flag = SRC_LINE; /* Finished step, just
5708 print source line. */
5710 source_flag = SRC_AND_LOC; /* Print location and
5713 case PRINT_SRC_AND_LOC:
5714 source_flag = SRC_AND_LOC; /* Print location and
5717 case PRINT_SRC_ONLY:
5718 source_flag = SRC_LINE;
5721 source_flag = SRC_LINE; /* something bogus */
5722 do_frame_printing = 0;
5725 internal_error (__FILE__, __LINE__, _("Unknown value."));
5728 /* The behavior of this routine with respect to the source
5730 SRC_LINE: Print only source line
5731 LOCATION: Print only location
5732 SRC_AND_LOC: Print location and source line. */
5733 if (do_frame_printing)
5734 print_stack_frame (get_selected_frame (NULL), 0, source_flag);
5736 /* Display the auto-display expressions. */
5741 /* Save the function value return registers, if we care.
5742 We might be about to restore their previous contents. */
5743 if (inferior_thread ()->control.proceed_to_finish)
5745 /* This should not be necessary. */
5747 regcache_xfree (stop_registers);
5749 /* NB: The copy goes through to the target picking up the value of
5750 all the registers. */
5751 stop_registers = regcache_dup (get_current_regcache ());
5754 if (stop_stack_dummy == STOP_STACK_DUMMY)
5756 /* Pop the empty frame that contains the stack dummy.
5757 This also restores inferior state prior to the call
5758 (struct infcall_suspend_state). */
5759 struct frame_info *frame = get_current_frame ();
5761 gdb_assert (get_frame_type (frame) == DUMMY_FRAME);
5763 /* frame_pop() calls reinit_frame_cache as the last thing it
5764 does which means there's currently no selected frame. We
5765 don't need to re-establish a selected frame if the dummy call
5766 returns normally, that will be done by
5767 restore_infcall_control_state. However, we do have to handle
5768 the case where the dummy call is returning after being
5769 stopped (e.g. the dummy call previously hit a breakpoint).
5770 We can't know which case we have so just always re-establish
5771 a selected frame here. */
5772 select_frame (get_current_frame ());
5776 annotate_stopped ();
5778 /* Suppress the stop observer if we're in the middle of:
5780 - a step n (n > 1), as there still more steps to be done.
5782 - a "finish" command, as the observer will be called in
5783 finish_command_continuation, so it can include the inferior
5784 function's return value.
5786 - calling an inferior function, as we pretend we inferior didn't
5787 run at all. The return value of the call is handled by the
5788 expression evaluator, through call_function_by_hand. */
5790 if (!target_has_execution
5791 || last.kind == TARGET_WAITKIND_SIGNALLED
5792 || last.kind == TARGET_WAITKIND_EXITED
5793 || (!inferior_thread ()->step_multi
5794 && !(inferior_thread ()->control.stop_bpstat
5795 && inferior_thread ()->control.proceed_to_finish)
5796 && !inferior_thread ()->control.in_infcall))
5798 if (!ptid_equal (inferior_ptid, null_ptid))
5799 observer_notify_normal_stop (inferior_thread ()->control.stop_bpstat,
5802 observer_notify_normal_stop (NULL, stop_print_frame);
5805 if (target_has_execution)
5807 if (last.kind != TARGET_WAITKIND_SIGNALLED
5808 && last.kind != TARGET_WAITKIND_EXITED)
5809 /* Delete the breakpoint we stopped at, if it wants to be deleted.
5810 Delete any breakpoint that is to be deleted at the next stop. */
5811 breakpoint_auto_delete (inferior_thread ()->control.stop_bpstat);
5814 /* Try to get rid of automatically added inferiors that are no
5815 longer needed. Keeping those around slows down things linearly.
5816 Note that this never removes the current inferior. */
5821 hook_stop_stub (void *cmd)
5823 execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
5828 signal_stop_state (int signo)
5830 return signal_stop[signo];
5834 signal_print_state (int signo)
5836 return signal_print[signo];
5840 signal_pass_state (int signo)
5842 return signal_program[signo];
5846 signal_stop_update (int signo, int state)
5848 int ret = signal_stop[signo];
5850 signal_stop[signo] = state;
5855 signal_print_update (int signo, int state)
5857 int ret = signal_print[signo];
5859 signal_print[signo] = state;
5864 signal_pass_update (int signo, int state)
5866 int ret = signal_program[signo];
5868 signal_program[signo] = state;
5873 sig_print_header (void)
5875 printf_filtered (_("Signal Stop\tPrint\tPass "
5876 "to program\tDescription\n"));
5880 sig_print_info (enum target_signal oursig)
5882 const char *name = target_signal_to_name (oursig);
5883 int name_padding = 13 - strlen (name);
5885 if (name_padding <= 0)
5888 printf_filtered ("%s", name);
5889 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
5890 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
5891 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
5892 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
5893 printf_filtered ("%s\n", target_signal_to_string (oursig));
5896 /* Specify how various signals in the inferior should be handled. */
5899 handle_command (char *args, int from_tty)
5902 int digits, wordlen;
5903 int sigfirst, signum, siglast;
5904 enum target_signal oursig;
5907 unsigned char *sigs;
5908 struct cleanup *old_chain;
5912 error_no_arg (_("signal to handle"));
5915 /* Allocate and zero an array of flags for which signals to handle. */
5917 nsigs = (int) TARGET_SIGNAL_LAST;
5918 sigs = (unsigned char *) alloca (nsigs);
5919 memset (sigs, 0, nsigs);
5921 /* Break the command line up into args. */
5923 argv = gdb_buildargv (args);
5924 old_chain = make_cleanup_freeargv (argv);
5926 /* Walk through the args, looking for signal oursigs, signal names, and
5927 actions. Signal numbers and signal names may be interspersed with
5928 actions, with the actions being performed for all signals cumulatively
5929 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
5931 while (*argv != NULL)
5933 wordlen = strlen (*argv);
5934 for (digits = 0; isdigit ((*argv)[digits]); digits++)
5938 sigfirst = siglast = -1;
5940 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
5942 /* Apply action to all signals except those used by the
5943 debugger. Silently skip those. */
5946 siglast = nsigs - 1;
5948 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
5950 SET_SIGS (nsigs, sigs, signal_stop);
5951 SET_SIGS (nsigs, sigs, signal_print);
5953 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
5955 UNSET_SIGS (nsigs, sigs, signal_program);
5957 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
5959 SET_SIGS (nsigs, sigs, signal_print);
5961 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
5963 SET_SIGS (nsigs, sigs, signal_program);
5965 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
5967 UNSET_SIGS (nsigs, sigs, signal_stop);
5969 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
5971 SET_SIGS (nsigs, sigs, signal_program);
5973 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
5975 UNSET_SIGS (nsigs, sigs, signal_print);
5976 UNSET_SIGS (nsigs, sigs, signal_stop);
5978 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
5980 UNSET_SIGS (nsigs, sigs, signal_program);
5982 else if (digits > 0)
5984 /* It is numeric. The numeric signal refers to our own
5985 internal signal numbering from target.h, not to host/target
5986 signal number. This is a feature; users really should be
5987 using symbolic names anyway, and the common ones like
5988 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
5990 sigfirst = siglast = (int)
5991 target_signal_from_command (atoi (*argv));
5992 if ((*argv)[digits] == '-')
5995 target_signal_from_command (atoi ((*argv) + digits + 1));
5997 if (sigfirst > siglast)
5999 /* Bet he didn't figure we'd think of this case... */
6007 oursig = target_signal_from_name (*argv);
6008 if (oursig != TARGET_SIGNAL_UNKNOWN)
6010 sigfirst = siglast = (int) oursig;
6014 /* Not a number and not a recognized flag word => complain. */
6015 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv);
6019 /* If any signal numbers or symbol names were found, set flags for
6020 which signals to apply actions to. */
6022 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
6024 switch ((enum target_signal) signum)
6026 case TARGET_SIGNAL_TRAP:
6027 case TARGET_SIGNAL_INT:
6028 if (!allsigs && !sigs[signum])
6030 if (query (_("%s is used by the debugger.\n\
6031 Are you sure you want to change it? "),
6032 target_signal_to_name ((enum target_signal) signum)))
6038 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6039 gdb_flush (gdb_stdout);
6043 case TARGET_SIGNAL_0:
6044 case TARGET_SIGNAL_DEFAULT:
6045 case TARGET_SIGNAL_UNKNOWN:
6046 /* Make sure that "all" doesn't print these. */
6057 for (signum = 0; signum < nsigs; signum++)
6060 target_notice_signals (inferior_ptid);
6064 /* Show the results. */
6065 sig_print_header ();
6066 for (; signum < nsigs; signum++)
6068 sig_print_info (signum);
6074 do_cleanups (old_chain);
6078 xdb_handle_command (char *args, int from_tty)
6081 struct cleanup *old_chain;
6084 error_no_arg (_("xdb command"));
6086 /* Break the command line up into args. */
6088 argv = gdb_buildargv (args);
6089 old_chain = make_cleanup_freeargv (argv);
6090 if (argv[1] != (char *) NULL)
6095 bufLen = strlen (argv[0]) + 20;
6096 argBuf = (char *) xmalloc (bufLen);
6100 enum target_signal oursig;
6102 oursig = target_signal_from_name (argv[0]);
6103 memset (argBuf, 0, bufLen);
6104 if (strcmp (argv[1], "Q") == 0)
6105 sprintf (argBuf, "%s %s", argv[0], "noprint");
6108 if (strcmp (argv[1], "s") == 0)
6110 if (!signal_stop[oursig])
6111 sprintf (argBuf, "%s %s", argv[0], "stop");
6113 sprintf (argBuf, "%s %s", argv[0], "nostop");
6115 else if (strcmp (argv[1], "i") == 0)
6117 if (!signal_program[oursig])
6118 sprintf (argBuf, "%s %s", argv[0], "pass");
6120 sprintf (argBuf, "%s %s", argv[0], "nopass");
6122 else if (strcmp (argv[1], "r") == 0)
6124 if (!signal_print[oursig])
6125 sprintf (argBuf, "%s %s", argv[0], "print");
6127 sprintf (argBuf, "%s %s", argv[0], "noprint");
6133 handle_command (argBuf, from_tty);
6135 printf_filtered (_("Invalid signal handling flag.\n"));
6140 do_cleanups (old_chain);
6143 /* Print current contents of the tables set by the handle command.
6144 It is possible we should just be printing signals actually used
6145 by the current target (but for things to work right when switching
6146 targets, all signals should be in the signal tables). */
6149 signals_info (char *signum_exp, int from_tty)
6151 enum target_signal oursig;
6153 sig_print_header ();
6157 /* First see if this is a symbol name. */
6158 oursig = target_signal_from_name (signum_exp);
6159 if (oursig == TARGET_SIGNAL_UNKNOWN)
6161 /* No, try numeric. */
6163 target_signal_from_command (parse_and_eval_long (signum_exp));
6165 sig_print_info (oursig);
6169 printf_filtered ("\n");
6170 /* These ugly casts brought to you by the native VAX compiler. */
6171 for (oursig = TARGET_SIGNAL_FIRST;
6172 (int) oursig < (int) TARGET_SIGNAL_LAST;
6173 oursig = (enum target_signal) ((int) oursig + 1))
6177 if (oursig != TARGET_SIGNAL_UNKNOWN
6178 && oursig != TARGET_SIGNAL_DEFAULT && oursig != TARGET_SIGNAL_0)
6179 sig_print_info (oursig);
6182 printf_filtered (_("\nUse the \"handle\" command "
6183 "to change these tables.\n"));
6186 /* The $_siginfo convenience variable is a bit special. We don't know
6187 for sure the type of the value until we actually have a chance to
6188 fetch the data. The type can change depending on gdbarch, so it it
6189 also dependent on which thread you have selected.
6191 1. making $_siginfo be an internalvar that creates a new value on
6194 2. making the value of $_siginfo be an lval_computed value. */
6196 /* This function implements the lval_computed support for reading a
6200 siginfo_value_read (struct value *v)
6202 LONGEST transferred;
6205 target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO,
6207 value_contents_all_raw (v),
6209 TYPE_LENGTH (value_type (v)));
6211 if (transferred != TYPE_LENGTH (value_type (v)))
6212 error (_("Unable to read siginfo"));
6215 /* This function implements the lval_computed support for writing a
6219 siginfo_value_write (struct value *v, struct value *fromval)
6221 LONGEST transferred;
6223 transferred = target_write (¤t_target,
6224 TARGET_OBJECT_SIGNAL_INFO,
6226 value_contents_all_raw (fromval),
6228 TYPE_LENGTH (value_type (fromval)));
6230 if (transferred != TYPE_LENGTH (value_type (fromval)))
6231 error (_("Unable to write siginfo"));
6234 static struct lval_funcs siginfo_value_funcs =
6240 /* Return a new value with the correct type for the siginfo object of
6241 the current thread using architecture GDBARCH. Return a void value
6242 if there's no object available. */
6244 static struct value *
6245 siginfo_make_value (struct gdbarch *gdbarch, struct internalvar *var)
6247 if (target_has_stack
6248 && !ptid_equal (inferior_ptid, null_ptid)
6249 && gdbarch_get_siginfo_type_p (gdbarch))
6251 struct type *type = gdbarch_get_siginfo_type (gdbarch);
6253 return allocate_computed_value (type, &siginfo_value_funcs, NULL);
6256 return allocate_value (builtin_type (gdbarch)->builtin_void);
6260 /* infcall_suspend_state contains state about the program itself like its
6261 registers and any signal it received when it last stopped.
6262 This state must be restored regardless of how the inferior function call
6263 ends (either successfully, or after it hits a breakpoint or signal)
6264 if the program is to properly continue where it left off. */
6266 struct infcall_suspend_state
6268 struct thread_suspend_state thread_suspend;
6269 struct inferior_suspend_state inferior_suspend;
6273 struct regcache *registers;
6275 /* Format of SIGINFO_DATA or NULL if it is not present. */
6276 struct gdbarch *siginfo_gdbarch;
6278 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
6279 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
6280 content would be invalid. */
6281 gdb_byte *siginfo_data;
6284 struct infcall_suspend_state *
6285 save_infcall_suspend_state (void)
6287 struct infcall_suspend_state *inf_state;
6288 struct thread_info *tp = inferior_thread ();
6289 struct inferior *inf = current_inferior ();
6290 struct regcache *regcache = get_current_regcache ();
6291 struct gdbarch *gdbarch = get_regcache_arch (regcache);
6292 gdb_byte *siginfo_data = NULL;
6294 if (gdbarch_get_siginfo_type_p (gdbarch))
6296 struct type *type = gdbarch_get_siginfo_type (gdbarch);
6297 size_t len = TYPE_LENGTH (type);
6298 struct cleanup *back_to;
6300 siginfo_data = xmalloc (len);
6301 back_to = make_cleanup (xfree, siginfo_data);
6303 if (target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
6304 siginfo_data, 0, len) == len)
6305 discard_cleanups (back_to);
6308 /* Errors ignored. */
6309 do_cleanups (back_to);
6310 siginfo_data = NULL;
6314 inf_state = XZALLOC (struct infcall_suspend_state);
6318 inf_state->siginfo_gdbarch = gdbarch;
6319 inf_state->siginfo_data = siginfo_data;
6322 inf_state->thread_suspend = tp->suspend;
6323 inf_state->inferior_suspend = inf->suspend;
6325 /* run_inferior_call will not use the signal due to its `proceed' call with
6326 TARGET_SIGNAL_0 anyway. */
6327 tp->suspend.stop_signal = TARGET_SIGNAL_0;
6329 inf_state->stop_pc = stop_pc;
6331 inf_state->registers = regcache_dup (regcache);
6336 /* Restore inferior session state to INF_STATE. */
6339 restore_infcall_suspend_state (struct infcall_suspend_state *inf_state)
6341 struct thread_info *tp = inferior_thread ();
6342 struct inferior *inf = current_inferior ();
6343 struct regcache *regcache = get_current_regcache ();
6344 struct gdbarch *gdbarch = get_regcache_arch (regcache);
6346 tp->suspend = inf_state->thread_suspend;
6347 inf->suspend = inf_state->inferior_suspend;
6349 stop_pc = inf_state->stop_pc;
6351 if (inf_state->siginfo_gdbarch == gdbarch)
6353 struct type *type = gdbarch_get_siginfo_type (gdbarch);
6354 size_t len = TYPE_LENGTH (type);
6356 /* Errors ignored. */
6357 target_write (¤t_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
6358 inf_state->siginfo_data, 0, len);
6361 /* The inferior can be gone if the user types "print exit(0)"
6362 (and perhaps other times). */
6363 if (target_has_execution)
6364 /* NB: The register write goes through to the target. */
6365 regcache_cpy (regcache, inf_state->registers);
6367 discard_infcall_suspend_state (inf_state);
6371 do_restore_infcall_suspend_state_cleanup (void *state)
6373 restore_infcall_suspend_state (state);
6377 make_cleanup_restore_infcall_suspend_state
6378 (struct infcall_suspend_state *inf_state)
6380 return make_cleanup (do_restore_infcall_suspend_state_cleanup, inf_state);
6384 discard_infcall_suspend_state (struct infcall_suspend_state *inf_state)
6386 regcache_xfree (inf_state->registers);
6387 xfree (inf_state->siginfo_data);
6392 get_infcall_suspend_state_regcache (struct infcall_suspend_state *inf_state)
6394 return inf_state->registers;
6397 /* infcall_control_state contains state regarding gdb's control of the
6398 inferior itself like stepping control. It also contains session state like
6399 the user's currently selected frame. */
6401 struct infcall_control_state
6403 struct thread_control_state thread_control;
6404 struct inferior_control_state inferior_control;
6407 enum stop_stack_kind stop_stack_dummy;
6408 int stopped_by_random_signal;
6409 int stop_after_trap;
6411 /* ID if the selected frame when the inferior function call was made. */
6412 struct frame_id selected_frame_id;
6415 /* Save all of the information associated with the inferior<==>gdb
6418 struct infcall_control_state *
6419 save_infcall_control_state (void)
6421 struct infcall_control_state *inf_status = xmalloc (sizeof (*inf_status));
6422 struct thread_info *tp = inferior_thread ();
6423 struct inferior *inf = current_inferior ();
6425 inf_status->thread_control = tp->control;
6426 inf_status->inferior_control = inf->control;
6428 tp->control.step_resume_breakpoint = NULL;
6429 tp->control.exception_resume_breakpoint = NULL;
6431 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
6432 chain. If caller's caller is walking the chain, they'll be happier if we
6433 hand them back the original chain when restore_infcall_control_state is
6435 tp->control.stop_bpstat = bpstat_copy (tp->control.stop_bpstat);
6438 inf_status->stop_stack_dummy = stop_stack_dummy;
6439 inf_status->stopped_by_random_signal = stopped_by_random_signal;
6440 inf_status->stop_after_trap = stop_after_trap;
6442 inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL));
6448 restore_selected_frame (void *args)
6450 struct frame_id *fid = (struct frame_id *) args;
6451 struct frame_info *frame;
6453 frame = frame_find_by_id (*fid);
6455 /* If inf_status->selected_frame_id is NULL, there was no previously
6459 warning (_("Unable to restore previously selected frame."));
6463 select_frame (frame);
6468 /* Restore inferior session state to INF_STATUS. */
6471 restore_infcall_control_state (struct infcall_control_state *inf_status)
6473 struct thread_info *tp = inferior_thread ();
6474 struct inferior *inf = current_inferior ();
6476 if (tp->control.step_resume_breakpoint)
6477 tp->control.step_resume_breakpoint->disposition = disp_del_at_next_stop;
6479 if (tp->control.exception_resume_breakpoint)
6480 tp->control.exception_resume_breakpoint->disposition
6481 = disp_del_at_next_stop;
6483 /* Handle the bpstat_copy of the chain. */
6484 bpstat_clear (&tp->control.stop_bpstat);
6486 tp->control = inf_status->thread_control;
6487 inf->control = inf_status->inferior_control;
6490 stop_stack_dummy = inf_status->stop_stack_dummy;
6491 stopped_by_random_signal = inf_status->stopped_by_random_signal;
6492 stop_after_trap = inf_status->stop_after_trap;
6494 if (target_has_stack)
6496 /* The point of catch_errors is that if the stack is clobbered,
6497 walking the stack might encounter a garbage pointer and
6498 error() trying to dereference it. */
6500 (restore_selected_frame, &inf_status->selected_frame_id,
6501 "Unable to restore previously selected frame:\n",
6502 RETURN_MASK_ERROR) == 0)
6503 /* Error in restoring the selected frame. Select the innermost
6505 select_frame (get_current_frame ());
6512 do_restore_infcall_control_state_cleanup (void *sts)
6514 restore_infcall_control_state (sts);
6518 make_cleanup_restore_infcall_control_state
6519 (struct infcall_control_state *inf_status)
6521 return make_cleanup (do_restore_infcall_control_state_cleanup, inf_status);
6525 discard_infcall_control_state (struct infcall_control_state *inf_status)
6527 if (inf_status->thread_control.step_resume_breakpoint)
6528 inf_status->thread_control.step_resume_breakpoint->disposition
6529 = disp_del_at_next_stop;
6531 if (inf_status->thread_control.exception_resume_breakpoint)
6532 inf_status->thread_control.exception_resume_breakpoint->disposition
6533 = disp_del_at_next_stop;
6535 /* See save_infcall_control_state for info on stop_bpstat. */
6536 bpstat_clear (&inf_status->thread_control.stop_bpstat);
6542 inferior_has_forked (ptid_t pid, ptid_t *child_pid)
6544 struct target_waitstatus last;
6547 get_last_target_status (&last_ptid, &last);
6549 if (last.kind != TARGET_WAITKIND_FORKED)
6552 if (!ptid_equal (last_ptid, pid))
6555 *child_pid = last.value.related_pid;
6560 inferior_has_vforked (ptid_t pid, ptid_t *child_pid)
6562 struct target_waitstatus last;
6565 get_last_target_status (&last_ptid, &last);
6567 if (last.kind != TARGET_WAITKIND_VFORKED)
6570 if (!ptid_equal (last_ptid, pid))
6573 *child_pid = last.value.related_pid;
6578 inferior_has_execd (ptid_t pid, char **execd_pathname)
6580 struct target_waitstatus last;
6583 get_last_target_status (&last_ptid, &last);
6585 if (last.kind != TARGET_WAITKIND_EXECD)
6588 if (!ptid_equal (last_ptid, pid))
6591 *execd_pathname = xstrdup (last.value.execd_pathname);
6596 inferior_has_called_syscall (ptid_t pid, int *syscall_number)
6598 struct target_waitstatus last;
6601 get_last_target_status (&last_ptid, &last);
6603 if (last.kind != TARGET_WAITKIND_SYSCALL_ENTRY &&
6604 last.kind != TARGET_WAITKIND_SYSCALL_RETURN)
6607 if (!ptid_equal (last_ptid, pid))
6610 *syscall_number = last.value.syscall_number;
6614 /* Oft used ptids */
6616 ptid_t minus_one_ptid;
6618 /* Create a ptid given the necessary PID, LWP, and TID components. */
6621 ptid_build (int pid, long lwp, long tid)
6631 /* Create a ptid from just a pid. */
6634 pid_to_ptid (int pid)
6636 return ptid_build (pid, 0, 0);
6639 /* Fetch the pid (process id) component from a ptid. */
6642 ptid_get_pid (ptid_t ptid)
6647 /* Fetch the lwp (lightweight process) component from a ptid. */
6650 ptid_get_lwp (ptid_t ptid)
6655 /* Fetch the tid (thread id) component from a ptid. */
6658 ptid_get_tid (ptid_t ptid)
6663 /* ptid_equal() is used to test equality of two ptids. */
6666 ptid_equal (ptid_t ptid1, ptid_t ptid2)
6668 return (ptid1.pid == ptid2.pid && ptid1.lwp == ptid2.lwp
6669 && ptid1.tid == ptid2.tid);
6672 /* Returns true if PTID represents a process. */
6675 ptid_is_pid (ptid_t ptid)
6677 if (ptid_equal (minus_one_ptid, ptid))
6679 if (ptid_equal (null_ptid, ptid))
6682 return (ptid_get_lwp (ptid) == 0 && ptid_get_tid (ptid) == 0);
6686 ptid_match (ptid_t ptid, ptid_t filter)
6688 /* Since both parameters have the same type, prevent easy mistakes
6690 gdb_assert (!ptid_equal (ptid, minus_one_ptid)
6691 && !ptid_equal (ptid, null_ptid));
6693 if (ptid_equal (filter, minus_one_ptid))
6695 if (ptid_is_pid (filter)
6696 && ptid_get_pid (ptid) == ptid_get_pid (filter))
6698 else if (ptid_equal (ptid, filter))
6704 /* restore_inferior_ptid() will be used by the cleanup machinery
6705 to restore the inferior_ptid value saved in a call to
6706 save_inferior_ptid(). */
6709 restore_inferior_ptid (void *arg)
6711 ptid_t *saved_ptid_ptr = arg;
6713 inferior_ptid = *saved_ptid_ptr;
6717 /* Save the value of inferior_ptid so that it may be restored by a
6718 later call to do_cleanups(). Returns the struct cleanup pointer
6719 needed for later doing the cleanup. */
6722 save_inferior_ptid (void)
6724 ptid_t *saved_ptid_ptr;
6726 saved_ptid_ptr = xmalloc (sizeof (ptid_t));
6727 *saved_ptid_ptr = inferior_ptid;
6728 return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
6732 /* User interface for reverse debugging:
6733 Set exec-direction / show exec-direction commands
6734 (returns error unless target implements to_set_exec_direction method). */
6736 enum exec_direction_kind execution_direction = EXEC_FORWARD;
6737 static const char exec_forward[] = "forward";
6738 static const char exec_reverse[] = "reverse";
6739 static const char *exec_direction = exec_forward;
6740 static const char *exec_direction_names[] = {
6747 set_exec_direction_func (char *args, int from_tty,
6748 struct cmd_list_element *cmd)
6750 if (target_can_execute_reverse)
6752 if (!strcmp (exec_direction, exec_forward))
6753 execution_direction = EXEC_FORWARD;
6754 else if (!strcmp (exec_direction, exec_reverse))
6755 execution_direction = EXEC_REVERSE;
6759 exec_direction = exec_forward;
6760 error (_("Target does not support this operation."));
6765 show_exec_direction_func (struct ui_file *out, int from_tty,
6766 struct cmd_list_element *cmd, const char *value)
6768 switch (execution_direction) {
6770 fprintf_filtered (out, _("Forward.\n"));
6773 fprintf_filtered (out, _("Reverse.\n"));
6777 fprintf_filtered (out, _("Forward (target `%s' does not "
6778 "support exec-direction).\n"),
6784 /* User interface for non-stop mode. */
6789 set_non_stop (char *args, int from_tty,
6790 struct cmd_list_element *c)
6792 if (target_has_execution)
6794 non_stop_1 = non_stop;
6795 error (_("Cannot change this setting while the inferior is running."));
6798 non_stop = non_stop_1;
6802 show_non_stop (struct ui_file *file, int from_tty,
6803 struct cmd_list_element *c, const char *value)
6805 fprintf_filtered (file,
6806 _("Controlling the inferior in non-stop mode is %s.\n"),
6811 show_schedule_multiple (struct ui_file *file, int from_tty,
6812 struct cmd_list_element *c, const char *value)
6814 fprintf_filtered (file, _("Resuming the execution of threads "
6815 "of all processes is %s.\n"), value);
6819 _initialize_infrun (void)
6824 add_info ("signals", signals_info, _("\
6825 What debugger does when program gets various signals.\n\
6826 Specify a signal as argument to print info on that signal only."));
6827 add_info_alias ("handle", "signals", 0);
6829 add_com ("handle", class_run, handle_command, _("\
6830 Specify how to handle a signal.\n\
6831 Args are signals and actions to apply to those signals.\n\
6832 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
6833 from 1-15 are allowed for compatibility with old versions of GDB.\n\
6834 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
6835 The special arg \"all\" is recognized to mean all signals except those\n\
6836 used by the debugger, typically SIGTRAP and SIGINT.\n\
6837 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
6838 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
6839 Stop means reenter debugger if this signal happens (implies print).\n\
6840 Print means print a message if this signal happens.\n\
6841 Pass means let program see this signal; otherwise program doesn't know.\n\
6842 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
6843 Pass and Stop may be combined."));
6846 add_com ("lz", class_info, signals_info, _("\
6847 What debugger does when program gets various signals.\n\
6848 Specify a signal as argument to print info on that signal only."));
6849 add_com ("z", class_run, xdb_handle_command, _("\
6850 Specify how to handle a signal.\n\
6851 Args are signals and actions to apply to those signals.\n\
6852 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
6853 from 1-15 are allowed for compatibility with old versions of GDB.\n\
6854 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
6855 The special arg \"all\" is recognized to mean all signals except those\n\
6856 used by the debugger, typically SIGTRAP and SIGINT.\n\
6857 Recognized actions include \"s\" (toggles between stop and nostop),\n\
6858 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
6859 nopass), \"Q\" (noprint)\n\
6860 Stop means reenter debugger if this signal happens (implies print).\n\
6861 Print means print a message if this signal happens.\n\
6862 Pass means let program see this signal; otherwise program doesn't know.\n\
6863 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
6864 Pass and Stop may be combined."));
6868 stop_command = add_cmd ("stop", class_obscure,
6869 not_just_help_class_command, _("\
6870 There is no `stop' command, but you can set a hook on `stop'.\n\
6871 This allows you to set a list of commands to be run each time execution\n\
6872 of the program stops."), &cmdlist);
6874 add_setshow_zinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\
6875 Set inferior debugging."), _("\
6876 Show inferior debugging."), _("\
6877 When non-zero, inferior specific debugging is enabled."),
6880 &setdebuglist, &showdebuglist);
6882 add_setshow_boolean_cmd ("displaced", class_maintenance,
6883 &debug_displaced, _("\
6884 Set displaced stepping debugging."), _("\
6885 Show displaced stepping debugging."), _("\
6886 When non-zero, displaced stepping specific debugging is enabled."),
6888 show_debug_displaced,
6889 &setdebuglist, &showdebuglist);
6891 add_setshow_boolean_cmd ("non-stop", no_class,
6893 Set whether gdb controls the inferior in non-stop mode."), _("\
6894 Show whether gdb controls the inferior in non-stop mode."), _("\
6895 When debugging a multi-threaded program and this setting is\n\
6896 off (the default, also called all-stop mode), when one thread stops\n\
6897 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
6898 all other threads in the program while you interact with the thread of\n\
6899 interest. When you continue or step a thread, you can allow the other\n\
6900 threads to run, or have them remain stopped, but while you inspect any\n\
6901 thread's state, all threads stop.\n\
6903 In non-stop mode, when one thread stops, other threads can continue\n\
6904 to run freely. You'll be able to step each thread independently,\n\
6905 leave it stopped or free to run as needed."),
6911 numsigs = (int) TARGET_SIGNAL_LAST;
6912 signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs);
6913 signal_print = (unsigned char *)
6914 xmalloc (sizeof (signal_print[0]) * numsigs);
6915 signal_program = (unsigned char *)
6916 xmalloc (sizeof (signal_program[0]) * numsigs);
6917 for (i = 0; i < numsigs; i++)
6920 signal_print[i] = 1;
6921 signal_program[i] = 1;
6924 /* Signals caused by debugger's own actions
6925 should not be given to the program afterwards. */
6926 signal_program[TARGET_SIGNAL_TRAP] = 0;
6927 signal_program[TARGET_SIGNAL_INT] = 0;
6929 /* Signals that are not errors should not normally enter the debugger. */
6930 signal_stop[TARGET_SIGNAL_ALRM] = 0;
6931 signal_print[TARGET_SIGNAL_ALRM] = 0;
6932 signal_stop[TARGET_SIGNAL_VTALRM] = 0;
6933 signal_print[TARGET_SIGNAL_VTALRM] = 0;
6934 signal_stop[TARGET_SIGNAL_PROF] = 0;
6935 signal_print[TARGET_SIGNAL_PROF] = 0;
6936 signal_stop[TARGET_SIGNAL_CHLD] = 0;
6937 signal_print[TARGET_SIGNAL_CHLD] = 0;
6938 signal_stop[TARGET_SIGNAL_IO] = 0;
6939 signal_print[TARGET_SIGNAL_IO] = 0;
6940 signal_stop[TARGET_SIGNAL_POLL] = 0;
6941 signal_print[TARGET_SIGNAL_POLL] = 0;
6942 signal_stop[TARGET_SIGNAL_URG] = 0;
6943 signal_print[TARGET_SIGNAL_URG] = 0;
6944 signal_stop[TARGET_SIGNAL_WINCH] = 0;
6945 signal_print[TARGET_SIGNAL_WINCH] = 0;
6946 signal_stop[TARGET_SIGNAL_PRIO] = 0;
6947 signal_print[TARGET_SIGNAL_PRIO] = 0;
6949 /* These signals are used internally by user-level thread
6950 implementations. (See signal(5) on Solaris.) Like the above
6951 signals, a healthy program receives and handles them as part of
6952 its normal operation. */
6953 signal_stop[TARGET_SIGNAL_LWP] = 0;
6954 signal_print[TARGET_SIGNAL_LWP] = 0;
6955 signal_stop[TARGET_SIGNAL_WAITING] = 0;
6956 signal_print[TARGET_SIGNAL_WAITING] = 0;
6957 signal_stop[TARGET_SIGNAL_CANCEL] = 0;
6958 signal_print[TARGET_SIGNAL_CANCEL] = 0;
6960 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support,
6961 &stop_on_solib_events, _("\
6962 Set stopping for shared library events."), _("\
6963 Show stopping for shared library events."), _("\
6964 If nonzero, gdb will give control to the user when the dynamic linker\n\
6965 notifies gdb of shared library events. The most common event of interest\n\
6966 to the user would be loading/unloading of a new library."),
6968 show_stop_on_solib_events,
6969 &setlist, &showlist);
6971 add_setshow_enum_cmd ("follow-fork-mode", class_run,
6972 follow_fork_mode_kind_names,
6973 &follow_fork_mode_string, _("\
6974 Set debugger response to a program call of fork or vfork."), _("\
6975 Show debugger response to a program call of fork or vfork."), _("\
6976 A fork or vfork creates a new process. follow-fork-mode can be:\n\
6977 parent - the original process is debugged after a fork\n\
6978 child - the new process is debugged after a fork\n\
6979 The unfollowed process will continue to run.\n\
6980 By default, the debugger will follow the parent process."),
6982 show_follow_fork_mode_string,
6983 &setlist, &showlist);
6985 add_setshow_enum_cmd ("follow-exec-mode", class_run,
6986 follow_exec_mode_names,
6987 &follow_exec_mode_string, _("\
6988 Set debugger response to a program call of exec."), _("\
6989 Show debugger response to a program call of exec."), _("\
6990 An exec call replaces the program image of a process.\n\
6992 follow-exec-mode can be:\n\
6994 new - the debugger creates a new inferior and rebinds the process\n\
6995 to this new inferior. The program the process was running before\n\
6996 the exec call can be restarted afterwards by restarting the original\n\
6999 same - the debugger keeps the process bound to the same inferior.\n\
7000 The new executable image replaces the previous executable loaded in\n\
7001 the inferior. Restarting the inferior after the exec call restarts\n\
7002 the executable the process was running after the exec call.\n\
7004 By default, the debugger will use the same inferior."),
7006 show_follow_exec_mode_string,
7007 &setlist, &showlist);
7009 add_setshow_enum_cmd ("scheduler-locking", class_run,
7010 scheduler_enums, &scheduler_mode, _("\
7011 Set mode for locking scheduler during execution."), _("\
7012 Show mode for locking scheduler during execution."), _("\
7013 off == no locking (threads may preempt at any time)\n\
7014 on == full locking (no thread except the current thread may run)\n\
7015 step == scheduler locked during every single-step operation.\n\
7016 In this mode, no other thread may run during a step command.\n\
7017 Other threads may run while stepping over a function call ('next')."),
7018 set_schedlock_func, /* traps on target vector */
7019 show_scheduler_mode,
7020 &setlist, &showlist);
7022 add_setshow_boolean_cmd ("schedule-multiple", class_run, &sched_multi, _("\
7023 Set mode for resuming threads of all processes."), _("\
7024 Show mode for resuming threads of all processes."), _("\
7025 When on, execution commands (such as 'continue' or 'next') resume all\n\
7026 threads of all processes. When off (which is the default), execution\n\
7027 commands only resume the threads of the current process. The set of\n\
7028 threads that are resumed is further refined by the scheduler-locking\n\
7029 mode (see help set scheduler-locking)."),
7031 show_schedule_multiple,
7032 &setlist, &showlist);
7034 add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\
7035 Set mode of the step operation."), _("\
7036 Show mode of the step operation."), _("\
7037 When set, doing a step over a function without debug line information\n\
7038 will stop at the first instruction of that function. Otherwise, the\n\
7039 function is skipped and the step command stops at a different source line."),
7041 show_step_stop_if_no_debug,
7042 &setlist, &showlist);
7044 add_setshow_enum_cmd ("displaced-stepping", class_run,
7045 can_use_displaced_stepping_enum,
7046 &can_use_displaced_stepping, _("\
7047 Set debugger's willingness to use displaced stepping."), _("\
7048 Show debugger's willingness to use displaced stepping."), _("\
7049 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7050 supported by the target architecture. If off, gdb will not use displaced\n\
7051 stepping to step over breakpoints, even if such is supported by the target\n\
7052 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7053 if the target architecture supports it and non-stop mode is active, but will not\n\
7054 use it in all-stop mode (see help set non-stop)."),
7056 show_can_use_displaced_stepping,
7057 &setlist, &showlist);
7059 add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names,
7060 &exec_direction, _("Set direction of execution.\n\
7061 Options are 'forward' or 'reverse'."),
7062 _("Show direction of execution (forward/reverse)."),
7063 _("Tells gdb whether to execute forward or backward."),
7064 set_exec_direction_func, show_exec_direction_func,
7065 &setlist, &showlist);
7067 /* Set/show detach-on-fork: user-settable mode. */
7069 add_setshow_boolean_cmd ("detach-on-fork", class_run, &detach_fork, _("\
7070 Set whether gdb will detach the child of a fork."), _("\
7071 Show whether gdb will detach the child of a fork."), _("\
7072 Tells gdb whether to detach the child of a fork."),
7073 NULL, NULL, &setlist, &showlist);
7075 /* ptid initializations */
7076 null_ptid = ptid_build (0, 0, 0);
7077 minus_one_ptid = ptid_build (-1, 0, 0);
7078 inferior_ptid = null_ptid;
7079 target_last_wait_ptid = minus_one_ptid;
7081 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed);
7082 observer_attach_thread_stop_requested (infrun_thread_stop_requested);
7083 observer_attach_thread_exit (infrun_thread_thread_exit);
7084 observer_attach_inferior_exit (infrun_inferior_exit);
7086 /* Explicitly create without lookup, since that tries to create a
7087 value with a void typed value, and when we get here, gdbarch
7088 isn't initialized yet. At this point, we're quite sure there
7089 isn't another convenience variable of the same name. */
7090 create_internalvar_type_lazy ("_siginfo", siginfo_make_value);
7092 add_setshow_boolean_cmd ("observer", no_class,
7093 &observer_mode_1, _("\
7094 Set whether gdb controls the inferior in observer mode."), _("\
7095 Show whether gdb controls the inferior in observer mode."), _("\
7096 In observer mode, GDB can get data from the inferior, but not\n\
7097 affect its execution. Registers and memory may not be changed,\n\
7098 breakpoints may not be set, and the program cannot be interrupted\n\