1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
5 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
6 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
8 This file is part of GDB.
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program. If not, see <http://www.gnu.org/licenses/>. */
24 #include "gdb_string.h"
29 #include "exceptions.h"
30 #include "breakpoint.h"
34 #include "cli/cli-script.h"
36 #include "gdbthread.h"
48 #include "dictionary.h"
50 #include "gdb_assert.h"
51 #include "mi/mi-common.h"
52 #include "event-top.h"
54 #include "inline-frame.h"
56 #include "tracepoint.h"
57 #include "continuations.h"
60 /* Prototypes for local functions */
62 static void signals_info (char *, int);
64 static void handle_command (char *, int);
66 static void sig_print_info (enum target_signal
);
68 static void sig_print_header (void);
70 static void resume_cleanups (void *);
72 static int hook_stop_stub (void *);
74 static int restore_selected_frame (void *);
76 static int follow_fork (void);
78 static void set_schedlock_func (char *args
, int from_tty
,
79 struct cmd_list_element
*c
);
81 static int currently_stepping (struct thread_info
*tp
);
83 static int currently_stepping_or_nexting_callback (struct thread_info
*tp
,
86 static void xdb_handle_command (char *args
, int from_tty
);
88 static int prepare_to_proceed (int);
90 static void print_exited_reason (int exitstatus
);
92 static void print_signal_exited_reason (enum target_signal siggnal
);
94 static void print_no_history_reason (void);
96 static void print_signal_received_reason (enum target_signal siggnal
);
98 static void print_end_stepping_range_reason (void);
100 void _initialize_infrun (void);
102 void nullify_last_target_wait_ptid (void);
104 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
106 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
108 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
110 /* When set, stop the 'step' command if we enter a function which has
111 no line number information. The normal behavior is that we step
112 over such function. */
113 int step_stop_if_no_debug
= 0;
115 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
116 struct cmd_list_element
*c
, const char *value
)
118 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
121 /* In asynchronous mode, but simulating synchronous execution. */
123 int sync_execution
= 0;
125 /* wait_for_inferior and normal_stop use this to notify the user
126 when the inferior stopped in a different thread than it had been
129 static ptid_t previous_inferior_ptid
;
131 /* Default behavior is to detach newly forked processes (legacy). */
134 int debug_displaced
= 0;
136 show_debug_displaced (struct ui_file
*file
, int from_tty
,
137 struct cmd_list_element
*c
, const char *value
)
139 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
142 int debug_infrun
= 0;
144 show_debug_infrun (struct ui_file
*file
, int from_tty
,
145 struct cmd_list_element
*c
, const char *value
)
147 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
150 /* If the program uses ELF-style shared libraries, then calls to
151 functions in shared libraries go through stubs, which live in a
152 table called the PLT (Procedure Linkage Table). The first time the
153 function is called, the stub sends control to the dynamic linker,
154 which looks up the function's real address, patches the stub so
155 that future calls will go directly to the function, and then passes
156 control to the function.
158 If we are stepping at the source level, we don't want to see any of
159 this --- we just want to skip over the stub and the dynamic linker.
160 The simple approach is to single-step until control leaves the
163 However, on some systems (e.g., Red Hat's 5.2 distribution) the
164 dynamic linker calls functions in the shared C library, so you
165 can't tell from the PC alone whether the dynamic linker is still
166 running. In this case, we use a step-resume breakpoint to get us
167 past the dynamic linker, as if we were using "next" to step over a
170 in_solib_dynsym_resolve_code() says whether we're in the dynamic
171 linker code or not. Normally, this means we single-step. However,
172 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
173 address where we can place a step-resume breakpoint to get past the
174 linker's symbol resolution function.
176 in_solib_dynsym_resolve_code() can generally be implemented in a
177 pretty portable way, by comparing the PC against the address ranges
178 of the dynamic linker's sections.
180 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
181 it depends on internal details of the dynamic linker. It's usually
182 not too hard to figure out where to put a breakpoint, but it
183 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
184 sanity checking. If it can't figure things out, returning zero and
185 getting the (possibly confusing) stepping behavior is better than
186 signalling an error, which will obscure the change in the
189 /* This function returns TRUE if pc is the address of an instruction
190 that lies within the dynamic linker (such as the event hook, or the
193 This function must be used only when a dynamic linker event has
194 been caught, and the inferior is being stepped out of the hook, or
195 undefined results are guaranteed. */
197 #ifndef SOLIB_IN_DYNAMIC_LINKER
198 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
201 /* "Observer mode" is somewhat like a more extreme version of
202 non-stop, in which all GDB operations that might affect the
203 target's execution have been disabled. */
205 static int non_stop_1
= 0;
207 int observer_mode
= 0;
208 static int observer_mode_1
= 0;
211 set_observer_mode (char *args
, int from_tty
,
212 struct cmd_list_element
*c
)
214 extern int pagination_enabled
;
216 if (target_has_execution
)
218 observer_mode_1
= observer_mode
;
219 error (_("Cannot change this setting while the inferior is running."));
222 observer_mode
= observer_mode_1
;
224 may_write_registers
= !observer_mode
;
225 may_write_memory
= !observer_mode
;
226 may_insert_breakpoints
= !observer_mode
;
227 may_insert_tracepoints
= !observer_mode
;
228 /* We can insert fast tracepoints in or out of observer mode,
229 but enable them if we're going into this mode. */
231 may_insert_fast_tracepoints
= 1;
232 may_stop
= !observer_mode
;
233 update_target_permissions ();
235 /* Going *into* observer mode we must force non-stop, then
236 going out we leave it that way. */
239 target_async_permitted
= 1;
240 pagination_enabled
= 0;
241 non_stop
= non_stop_1
= 1;
245 printf_filtered (_("Observer mode is now %s.\n"),
246 (observer_mode
? "on" : "off"));
250 show_observer_mode (struct ui_file
*file
, int from_tty
,
251 struct cmd_list_element
*c
, const char *value
)
253 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
256 /* This updates the value of observer mode based on changes in
257 permissions. Note that we are deliberately ignoring the values of
258 may-write-registers and may-write-memory, since the user may have
259 reason to enable these during a session, for instance to turn on a
260 debugging-related global. */
263 update_observer_mode (void)
267 newval
= (!may_insert_breakpoints
268 && !may_insert_tracepoints
269 && may_insert_fast_tracepoints
273 /* Let the user know if things change. */
274 if (newval
!= observer_mode
)
275 printf_filtered (_("Observer mode is now %s.\n"),
276 (newval
? "on" : "off"));
278 observer_mode
= observer_mode_1
= newval
;
281 /* Tables of how to react to signals; the user sets them. */
283 static unsigned char *signal_stop
;
284 static unsigned char *signal_print
;
285 static unsigned char *signal_program
;
287 /* Table of signals that the target may silently handle.
288 This is automatically determined from the flags above,
289 and simply cached here. */
290 static unsigned char *signal_pass
;
292 #define SET_SIGS(nsigs,sigs,flags) \
294 int signum = (nsigs); \
295 while (signum-- > 0) \
296 if ((sigs)[signum]) \
297 (flags)[signum] = 1; \
300 #define UNSET_SIGS(nsigs,sigs,flags) \
302 int signum = (nsigs); \
303 while (signum-- > 0) \
304 if ((sigs)[signum]) \
305 (flags)[signum] = 0; \
308 /* Value to pass to target_resume() to cause all threads to resume. */
310 #define RESUME_ALL minus_one_ptid
312 /* Command list pointer for the "stop" placeholder. */
314 static struct cmd_list_element
*stop_command
;
316 /* Function inferior was in as of last step command. */
318 static struct symbol
*step_start_function
;
320 /* Nonzero if we want to give control to the user when we're notified
321 of shared library events by the dynamic linker. */
322 int stop_on_solib_events
;
324 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
325 struct cmd_list_element
*c
, const char *value
)
327 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
331 /* Nonzero means expecting a trace trap
332 and should stop the inferior and return silently when it happens. */
336 /* Save register contents here when executing a "finish" command or are
337 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
338 Thus this contains the return value from the called function (assuming
339 values are returned in a register). */
341 struct regcache
*stop_registers
;
343 /* Nonzero after stop if current stack frame should be printed. */
345 static int stop_print_frame
;
347 /* This is a cached copy of the pid/waitstatus of the last event
348 returned by target_wait()/deprecated_target_wait_hook(). This
349 information is returned by get_last_target_status(). */
350 static ptid_t target_last_wait_ptid
;
351 static struct target_waitstatus target_last_waitstatus
;
353 static void context_switch (ptid_t ptid
);
355 void init_thread_stepping_state (struct thread_info
*tss
);
357 void init_infwait_state (void);
359 static const char follow_fork_mode_child
[] = "child";
360 static const char follow_fork_mode_parent
[] = "parent";
362 static const char *follow_fork_mode_kind_names
[] = {
363 follow_fork_mode_child
,
364 follow_fork_mode_parent
,
368 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
370 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
371 struct cmd_list_element
*c
, const char *value
)
373 fprintf_filtered (file
,
374 _("Debugger response to a program "
375 "call of fork or vfork is \"%s\".\n"),
380 /* Tell the target to follow the fork we're stopped at. Returns true
381 if the inferior should be resumed; false, if the target for some
382 reason decided it's best not to resume. */
387 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
388 int should_resume
= 1;
389 struct thread_info
*tp
;
391 /* Copy user stepping state to the new inferior thread. FIXME: the
392 followed fork child thread should have a copy of most of the
393 parent thread structure's run control related fields, not just these.
394 Initialized to avoid "may be used uninitialized" warnings from gcc. */
395 struct breakpoint
*step_resume_breakpoint
= NULL
;
396 struct breakpoint
*exception_resume_breakpoint
= NULL
;
397 CORE_ADDR step_range_start
= 0;
398 CORE_ADDR step_range_end
= 0;
399 struct frame_id step_frame_id
= { 0 };
404 struct target_waitstatus wait_status
;
406 /* Get the last target status returned by target_wait(). */
407 get_last_target_status (&wait_ptid
, &wait_status
);
409 /* If not stopped at a fork event, then there's nothing else to
411 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
412 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
415 /* Check if we switched over from WAIT_PTID, since the event was
417 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
418 && !ptid_equal (inferior_ptid
, wait_ptid
))
420 /* We did. Switch back to WAIT_PTID thread, to tell the
421 target to follow it (in either direction). We'll
422 afterwards refuse to resume, and inform the user what
424 switch_to_thread (wait_ptid
);
429 tp
= inferior_thread ();
431 /* If there were any forks/vforks that were caught and are now to be
432 followed, then do so now. */
433 switch (tp
->pending_follow
.kind
)
435 case TARGET_WAITKIND_FORKED
:
436 case TARGET_WAITKIND_VFORKED
:
438 ptid_t parent
, child
;
440 /* If the user did a next/step, etc, over a fork call,
441 preserve the stepping state in the fork child. */
442 if (follow_child
&& should_resume
)
444 step_resume_breakpoint
= clone_momentary_breakpoint
445 (tp
->control
.step_resume_breakpoint
);
446 step_range_start
= tp
->control
.step_range_start
;
447 step_range_end
= tp
->control
.step_range_end
;
448 step_frame_id
= tp
->control
.step_frame_id
;
449 exception_resume_breakpoint
450 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
452 /* For now, delete the parent's sr breakpoint, otherwise,
453 parent/child sr breakpoints are considered duplicates,
454 and the child version will not be installed. Remove
455 this when the breakpoints module becomes aware of
456 inferiors and address spaces. */
457 delete_step_resume_breakpoint (tp
);
458 tp
->control
.step_range_start
= 0;
459 tp
->control
.step_range_end
= 0;
460 tp
->control
.step_frame_id
= null_frame_id
;
461 delete_exception_resume_breakpoint (tp
);
464 parent
= inferior_ptid
;
465 child
= tp
->pending_follow
.value
.related_pid
;
467 /* Tell the target to do whatever is necessary to follow
468 either parent or child. */
469 if (target_follow_fork (follow_child
))
471 /* Target refused to follow, or there's some other reason
472 we shouldn't resume. */
477 /* This pending follow fork event is now handled, one way
478 or another. The previous selected thread may be gone
479 from the lists by now, but if it is still around, need
480 to clear the pending follow request. */
481 tp
= find_thread_ptid (parent
);
483 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
485 /* This makes sure we don't try to apply the "Switched
486 over from WAIT_PID" logic above. */
487 nullify_last_target_wait_ptid ();
489 /* If we followed the child, switch to it... */
492 switch_to_thread (child
);
494 /* ... and preserve the stepping state, in case the
495 user was stepping over the fork call. */
498 tp
= inferior_thread ();
499 tp
->control
.step_resume_breakpoint
500 = step_resume_breakpoint
;
501 tp
->control
.step_range_start
= step_range_start
;
502 tp
->control
.step_range_end
= step_range_end
;
503 tp
->control
.step_frame_id
= step_frame_id
;
504 tp
->control
.exception_resume_breakpoint
505 = exception_resume_breakpoint
;
509 /* If we get here, it was because we're trying to
510 resume from a fork catchpoint, but, the user
511 has switched threads away from the thread that
512 forked. In that case, the resume command
513 issued is most likely not applicable to the
514 child, so just warn, and refuse to resume. */
515 warning (_("Not resuming: switched threads "
516 "before following fork child.\n"));
519 /* Reset breakpoints in the child as appropriate. */
520 follow_inferior_reset_breakpoints ();
523 switch_to_thread (parent
);
527 case TARGET_WAITKIND_SPURIOUS
:
528 /* Nothing to follow. */
531 internal_error (__FILE__
, __LINE__
,
532 "Unexpected pending_follow.kind %d\n",
533 tp
->pending_follow
.kind
);
537 return should_resume
;
541 follow_inferior_reset_breakpoints (void)
543 struct thread_info
*tp
= inferior_thread ();
545 /* Was there a step_resume breakpoint? (There was if the user
546 did a "next" at the fork() call.) If so, explicitly reset its
549 step_resumes are a form of bp that are made to be per-thread.
550 Since we created the step_resume bp when the parent process
551 was being debugged, and now are switching to the child process,
552 from the breakpoint package's viewpoint, that's a switch of
553 "threads". We must update the bp's notion of which thread
554 it is for, or it'll be ignored when it triggers. */
556 if (tp
->control
.step_resume_breakpoint
)
557 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
559 if (tp
->control
.exception_resume_breakpoint
)
560 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
562 /* Reinsert all breakpoints in the child. The user may have set
563 breakpoints after catching the fork, in which case those
564 were never set in the child, but only in the parent. This makes
565 sure the inserted breakpoints match the breakpoint list. */
567 breakpoint_re_set ();
568 insert_breakpoints ();
571 /* The child has exited or execed: resume threads of the parent the
572 user wanted to be executing. */
575 proceed_after_vfork_done (struct thread_info
*thread
,
578 int pid
= * (int *) arg
;
580 if (ptid_get_pid (thread
->ptid
) == pid
581 && is_running (thread
->ptid
)
582 && !is_executing (thread
->ptid
)
583 && !thread
->stop_requested
584 && thread
->suspend
.stop_signal
== TARGET_SIGNAL_0
)
587 fprintf_unfiltered (gdb_stdlog
,
588 "infrun: resuming vfork parent thread %s\n",
589 target_pid_to_str (thread
->ptid
));
591 switch_to_thread (thread
->ptid
);
592 clear_proceed_status ();
593 proceed ((CORE_ADDR
) -1, TARGET_SIGNAL_DEFAULT
, 0);
599 /* Called whenever we notice an exec or exit event, to handle
600 detaching or resuming a vfork parent. */
603 handle_vfork_child_exec_or_exit (int exec
)
605 struct inferior
*inf
= current_inferior ();
607 if (inf
->vfork_parent
)
609 int resume_parent
= -1;
611 /* This exec or exit marks the end of the shared memory region
612 between the parent and the child. If the user wanted to
613 detach from the parent, now is the time. */
615 if (inf
->vfork_parent
->pending_detach
)
617 struct thread_info
*tp
;
618 struct cleanup
*old_chain
;
619 struct program_space
*pspace
;
620 struct address_space
*aspace
;
622 /* follow-fork child, detach-on-fork on. */
624 old_chain
= make_cleanup_restore_current_thread ();
626 /* We're letting loose of the parent. */
627 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
628 switch_to_thread (tp
->ptid
);
630 /* We're about to detach from the parent, which implicitly
631 removes breakpoints from its address space. There's a
632 catch here: we want to reuse the spaces for the child,
633 but, parent/child are still sharing the pspace at this
634 point, although the exec in reality makes the kernel give
635 the child a fresh set of new pages. The problem here is
636 that the breakpoints module being unaware of this, would
637 likely chose the child process to write to the parent
638 address space. Swapping the child temporarily away from
639 the spaces has the desired effect. Yes, this is "sort
642 pspace
= inf
->pspace
;
643 aspace
= inf
->aspace
;
647 if (debug_infrun
|| info_verbose
)
649 target_terminal_ours ();
652 fprintf_filtered (gdb_stdlog
,
653 "Detaching vfork parent process "
654 "%d after child exec.\n",
655 inf
->vfork_parent
->pid
);
657 fprintf_filtered (gdb_stdlog
,
658 "Detaching vfork parent process "
659 "%d after child exit.\n",
660 inf
->vfork_parent
->pid
);
663 target_detach (NULL
, 0);
666 inf
->pspace
= pspace
;
667 inf
->aspace
= aspace
;
669 do_cleanups (old_chain
);
673 /* We're staying attached to the parent, so, really give the
674 child a new address space. */
675 inf
->pspace
= add_program_space (maybe_new_address_space ());
676 inf
->aspace
= inf
->pspace
->aspace
;
678 set_current_program_space (inf
->pspace
);
680 resume_parent
= inf
->vfork_parent
->pid
;
682 /* Break the bonds. */
683 inf
->vfork_parent
->vfork_child
= NULL
;
687 struct cleanup
*old_chain
;
688 struct program_space
*pspace
;
690 /* If this is a vfork child exiting, then the pspace and
691 aspaces were shared with the parent. Since we're
692 reporting the process exit, we'll be mourning all that is
693 found in the address space, and switching to null_ptid,
694 preparing to start a new inferior. But, since we don't
695 want to clobber the parent's address/program spaces, we
696 go ahead and create a new one for this exiting
699 /* Switch to null_ptid, so that clone_program_space doesn't want
700 to read the selected frame of a dead process. */
701 old_chain
= save_inferior_ptid ();
702 inferior_ptid
= null_ptid
;
704 /* This inferior is dead, so avoid giving the breakpoints
705 module the option to write through to it (cloning a
706 program space resets breakpoints). */
709 pspace
= add_program_space (maybe_new_address_space ());
710 set_current_program_space (pspace
);
712 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
713 inf
->pspace
= pspace
;
714 inf
->aspace
= pspace
->aspace
;
716 /* Put back inferior_ptid. We'll continue mourning this
718 do_cleanups (old_chain
);
720 resume_parent
= inf
->vfork_parent
->pid
;
721 /* Break the bonds. */
722 inf
->vfork_parent
->vfork_child
= NULL
;
725 inf
->vfork_parent
= NULL
;
727 gdb_assert (current_program_space
== inf
->pspace
);
729 if (non_stop
&& resume_parent
!= -1)
731 /* If the user wanted the parent to be running, let it go
733 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
736 fprintf_unfiltered (gdb_stdlog
,
737 "infrun: resuming vfork parent process %d\n",
740 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
742 do_cleanups (old_chain
);
747 /* Enum strings for "set|show displaced-stepping". */
749 static const char follow_exec_mode_new
[] = "new";
750 static const char follow_exec_mode_same
[] = "same";
751 static const char *follow_exec_mode_names
[] =
753 follow_exec_mode_new
,
754 follow_exec_mode_same
,
758 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
760 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
761 struct cmd_list_element
*c
, const char *value
)
763 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
766 /* EXECD_PATHNAME is assumed to be non-NULL. */
769 follow_exec (ptid_t pid
, char *execd_pathname
)
771 struct thread_info
*th
= inferior_thread ();
772 struct inferior
*inf
= current_inferior ();
774 /* This is an exec event that we actually wish to pay attention to.
775 Refresh our symbol table to the newly exec'd program, remove any
778 If there are breakpoints, they aren't really inserted now,
779 since the exec() transformed our inferior into a fresh set
782 We want to preserve symbolic breakpoints on the list, since
783 we have hopes that they can be reset after the new a.out's
784 symbol table is read.
786 However, any "raw" breakpoints must be removed from the list
787 (e.g., the solib bp's), since their address is probably invalid
790 And, we DON'T want to call delete_breakpoints() here, since
791 that may write the bp's "shadow contents" (the instruction
792 value that was overwritten witha TRAP instruction). Since
793 we now have a new a.out, those shadow contents aren't valid. */
795 mark_breakpoints_out ();
797 update_breakpoints_after_exec ();
799 /* If there was one, it's gone now. We cannot truly step-to-next
800 statement through an exec(). */
801 th
->control
.step_resume_breakpoint
= NULL
;
802 th
->control
.exception_resume_breakpoint
= NULL
;
803 th
->control
.step_range_start
= 0;
804 th
->control
.step_range_end
= 0;
806 /* The target reports the exec event to the main thread, even if
807 some other thread does the exec, and even if the main thread was
808 already stopped --- if debugging in non-stop mode, it's possible
809 the user had the main thread held stopped in the previous image
810 --- release it now. This is the same behavior as step-over-exec
811 with scheduler-locking on in all-stop mode. */
812 th
->stop_requested
= 0;
814 /* What is this a.out's name? */
815 printf_unfiltered (_("%s is executing new program: %s\n"),
816 target_pid_to_str (inferior_ptid
),
819 /* We've followed the inferior through an exec. Therefore, the
820 inferior has essentially been killed & reborn. */
822 gdb_flush (gdb_stdout
);
824 breakpoint_init_inferior (inf_execd
);
826 if (gdb_sysroot
&& *gdb_sysroot
)
828 char *name
= alloca (strlen (gdb_sysroot
)
829 + strlen (execd_pathname
)
832 strcpy (name
, gdb_sysroot
);
833 strcat (name
, execd_pathname
);
834 execd_pathname
= name
;
837 /* Reset the shared library package. This ensures that we get a
838 shlib event when the child reaches "_start", at which point the
839 dld will have had a chance to initialize the child. */
840 /* Also, loading a symbol file below may trigger symbol lookups, and
841 we don't want those to be satisfied by the libraries of the
842 previous incarnation of this process. */
843 no_shared_libraries (NULL
, 0);
845 if (follow_exec_mode_string
== follow_exec_mode_new
)
847 struct program_space
*pspace
;
849 /* The user wants to keep the old inferior and program spaces
850 around. Create a new fresh one, and switch to it. */
852 inf
= add_inferior (current_inferior ()->pid
);
853 pspace
= add_program_space (maybe_new_address_space ());
854 inf
->pspace
= pspace
;
855 inf
->aspace
= pspace
->aspace
;
857 exit_inferior_num_silent (current_inferior ()->num
);
859 set_current_inferior (inf
);
860 set_current_program_space (pspace
);
863 gdb_assert (current_program_space
== inf
->pspace
);
865 /* That a.out is now the one to use. */
866 exec_file_attach (execd_pathname
, 0);
868 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
869 (Position Independent Executable) main symbol file will get applied by
870 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
871 the breakpoints with the zero displacement. */
873 symbol_file_add (execd_pathname
, SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
,
876 set_initial_language ();
878 #ifdef SOLIB_CREATE_INFERIOR_HOOK
879 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid
));
881 solib_create_inferior_hook (0);
884 jit_inferior_created_hook ();
886 breakpoint_re_set ();
888 /* Reinsert all breakpoints. (Those which were symbolic have
889 been reset to the proper address in the new a.out, thanks
890 to symbol_file_command...). */
891 insert_breakpoints ();
893 /* The next resume of this inferior should bring it to the shlib
894 startup breakpoints. (If the user had also set bp's on
895 "main" from the old (parent) process, then they'll auto-
896 matically get reset there in the new process.). */
899 /* Non-zero if we just simulating a single-step. This is needed
900 because we cannot remove the breakpoints in the inferior process
901 until after the `wait' in `wait_for_inferior'. */
902 static int singlestep_breakpoints_inserted_p
= 0;
904 /* The thread we inserted single-step breakpoints for. */
905 static ptid_t singlestep_ptid
;
907 /* PC when we started this single-step. */
908 static CORE_ADDR singlestep_pc
;
910 /* If another thread hit the singlestep breakpoint, we save the original
911 thread here so that we can resume single-stepping it later. */
912 static ptid_t saved_singlestep_ptid
;
913 static int stepping_past_singlestep_breakpoint
;
915 /* If not equal to null_ptid, this means that after stepping over breakpoint
916 is finished, we need to switch to deferred_step_ptid, and step it.
918 The use case is when one thread has hit a breakpoint, and then the user
919 has switched to another thread and issued 'step'. We need to step over
920 breakpoint in the thread which hit the breakpoint, but then continue
921 stepping the thread user has selected. */
922 static ptid_t deferred_step_ptid
;
924 /* Displaced stepping. */
926 /* In non-stop debugging mode, we must take special care to manage
927 breakpoints properly; in particular, the traditional strategy for
928 stepping a thread past a breakpoint it has hit is unsuitable.
929 'Displaced stepping' is a tactic for stepping one thread past a
930 breakpoint it has hit while ensuring that other threads running
931 concurrently will hit the breakpoint as they should.
933 The traditional way to step a thread T off a breakpoint in a
934 multi-threaded program in all-stop mode is as follows:
936 a0) Initially, all threads are stopped, and breakpoints are not
938 a1) We single-step T, leaving breakpoints uninserted.
939 a2) We insert breakpoints, and resume all threads.
941 In non-stop debugging, however, this strategy is unsuitable: we
942 don't want to have to stop all threads in the system in order to
943 continue or step T past a breakpoint. Instead, we use displaced
946 n0) Initially, T is stopped, other threads are running, and
947 breakpoints are inserted.
948 n1) We copy the instruction "under" the breakpoint to a separate
949 location, outside the main code stream, making any adjustments
950 to the instruction, register, and memory state as directed by
952 n2) We single-step T over the instruction at its new location.
953 n3) We adjust the resulting register and memory state as directed
954 by T's architecture. This includes resetting T's PC to point
955 back into the main instruction stream.
958 This approach depends on the following gdbarch methods:
960 - gdbarch_max_insn_length and gdbarch_displaced_step_location
961 indicate where to copy the instruction, and how much space must
962 be reserved there. We use these in step n1.
964 - gdbarch_displaced_step_copy_insn copies a instruction to a new
965 address, and makes any necessary adjustments to the instruction,
966 register contents, and memory. We use this in step n1.
968 - gdbarch_displaced_step_fixup adjusts registers and memory after
969 we have successfuly single-stepped the instruction, to yield the
970 same effect the instruction would have had if we had executed it
971 at its original address. We use this in step n3.
973 - gdbarch_displaced_step_free_closure provides cleanup.
975 The gdbarch_displaced_step_copy_insn and
976 gdbarch_displaced_step_fixup functions must be written so that
977 copying an instruction with gdbarch_displaced_step_copy_insn,
978 single-stepping across the copied instruction, and then applying
979 gdbarch_displaced_insn_fixup should have the same effects on the
980 thread's memory and registers as stepping the instruction in place
981 would have. Exactly which responsibilities fall to the copy and
982 which fall to the fixup is up to the author of those functions.
984 See the comments in gdbarch.sh for details.
986 Note that displaced stepping and software single-step cannot
987 currently be used in combination, although with some care I think
988 they could be made to. Software single-step works by placing
989 breakpoints on all possible subsequent instructions; if the
990 displaced instruction is a PC-relative jump, those breakpoints
991 could fall in very strange places --- on pages that aren't
992 executable, or at addresses that are not proper instruction
993 boundaries. (We do generally let other threads run while we wait
994 to hit the software single-step breakpoint, and they might
995 encounter such a corrupted instruction.) One way to work around
996 this would be to have gdbarch_displaced_step_copy_insn fully
997 simulate the effect of PC-relative instructions (and return NULL)
998 on architectures that use software single-stepping.
1000 In non-stop mode, we can have independent and simultaneous step
1001 requests, so more than one thread may need to simultaneously step
1002 over a breakpoint. The current implementation assumes there is
1003 only one scratch space per process. In this case, we have to
1004 serialize access to the scratch space. If thread A wants to step
1005 over a breakpoint, but we are currently waiting for some other
1006 thread to complete a displaced step, we leave thread A stopped and
1007 place it in the displaced_step_request_queue. Whenever a displaced
1008 step finishes, we pick the next thread in the queue and start a new
1009 displaced step operation on it. See displaced_step_prepare and
1010 displaced_step_fixup for details. */
1012 struct displaced_step_request
1015 struct displaced_step_request
*next
;
1018 /* Per-inferior displaced stepping state. */
1019 struct displaced_step_inferior_state
1021 /* Pointer to next in linked list. */
1022 struct displaced_step_inferior_state
*next
;
1024 /* The process this displaced step state refers to. */
1027 /* A queue of pending displaced stepping requests. One entry per
1028 thread that needs to do a displaced step. */
1029 struct displaced_step_request
*step_request_queue
;
1031 /* If this is not null_ptid, this is the thread carrying out a
1032 displaced single-step in process PID. This thread's state will
1033 require fixing up once it has completed its step. */
1036 /* The architecture the thread had when we stepped it. */
1037 struct gdbarch
*step_gdbarch
;
1039 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1040 for post-step cleanup. */
1041 struct displaced_step_closure
*step_closure
;
1043 /* The address of the original instruction, and the copy we
1045 CORE_ADDR step_original
, step_copy
;
1047 /* Saved contents of copy area. */
1048 gdb_byte
*step_saved_copy
;
1051 /* The list of states of processes involved in displaced stepping
1053 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1055 /* Get the displaced stepping state of process PID. */
1057 static struct displaced_step_inferior_state
*
1058 get_displaced_stepping_state (int pid
)
1060 struct displaced_step_inferior_state
*state
;
1062 for (state
= displaced_step_inferior_states
;
1064 state
= state
->next
)
1065 if (state
->pid
== pid
)
1071 /* Add a new displaced stepping state for process PID to the displaced
1072 stepping state list, or return a pointer to an already existing
1073 entry, if it already exists. Never returns NULL. */
1075 static struct displaced_step_inferior_state
*
1076 add_displaced_stepping_state (int pid
)
1078 struct displaced_step_inferior_state
*state
;
1080 for (state
= displaced_step_inferior_states
;
1082 state
= state
->next
)
1083 if (state
->pid
== pid
)
1086 state
= xcalloc (1, sizeof (*state
));
1088 state
->next
= displaced_step_inferior_states
;
1089 displaced_step_inferior_states
= state
;
1094 /* If inferior is in displaced stepping, and ADDR equals to starting address
1095 of copy area, return corresponding displaced_step_closure. Otherwise,
1098 struct displaced_step_closure
*
1099 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1101 struct displaced_step_inferior_state
*displaced
1102 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1104 /* If checking the mode of displaced instruction in copy area. */
1105 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1106 && (displaced
->step_copy
== addr
))
1107 return displaced
->step_closure
;
1112 /* Remove the displaced stepping state of process PID. */
1115 remove_displaced_stepping_state (int pid
)
1117 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1119 gdb_assert (pid
!= 0);
1121 it
= displaced_step_inferior_states
;
1122 prev_next_p
= &displaced_step_inferior_states
;
1127 *prev_next_p
= it
->next
;
1132 prev_next_p
= &it
->next
;
1138 infrun_inferior_exit (struct inferior
*inf
)
1140 remove_displaced_stepping_state (inf
->pid
);
1143 /* Enum strings for "set|show displaced-stepping". */
1145 static const char can_use_displaced_stepping_auto
[] = "auto";
1146 static const char can_use_displaced_stepping_on
[] = "on";
1147 static const char can_use_displaced_stepping_off
[] = "off";
1148 static const char *can_use_displaced_stepping_enum
[] =
1150 can_use_displaced_stepping_auto
,
1151 can_use_displaced_stepping_on
,
1152 can_use_displaced_stepping_off
,
1156 /* If ON, and the architecture supports it, GDB will use displaced
1157 stepping to step over breakpoints. If OFF, or if the architecture
1158 doesn't support it, GDB will instead use the traditional
1159 hold-and-step approach. If AUTO (which is the default), GDB will
1160 decide which technique to use to step over breakpoints depending on
1161 which of all-stop or non-stop mode is active --- displaced stepping
1162 in non-stop mode; hold-and-step in all-stop mode. */
1164 static const char *can_use_displaced_stepping
=
1165 can_use_displaced_stepping_auto
;
1168 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1169 struct cmd_list_element
*c
,
1172 if (can_use_displaced_stepping
== can_use_displaced_stepping_auto
)
1173 fprintf_filtered (file
,
1174 _("Debugger's willingness to use displaced stepping "
1175 "to step over breakpoints is %s (currently %s).\n"),
1176 value
, non_stop
? "on" : "off");
1178 fprintf_filtered (file
,
1179 _("Debugger's willingness to use displaced stepping "
1180 "to step over breakpoints is %s.\n"), value
);
1183 /* Return non-zero if displaced stepping can/should be used to step
1184 over breakpoints. */
1187 use_displaced_stepping (struct gdbarch
*gdbarch
)
1189 return (((can_use_displaced_stepping
== can_use_displaced_stepping_auto
1191 || can_use_displaced_stepping
== can_use_displaced_stepping_on
)
1192 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1193 && !RECORD_IS_USED
);
1196 /* Clean out any stray displaced stepping state. */
1198 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1200 /* Indicate that there is no cleanup pending. */
1201 displaced
->step_ptid
= null_ptid
;
1203 if (displaced
->step_closure
)
1205 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1206 displaced
->step_closure
);
1207 displaced
->step_closure
= NULL
;
1212 displaced_step_clear_cleanup (void *arg
)
1214 struct displaced_step_inferior_state
*state
= arg
;
1216 displaced_step_clear (state
);
1219 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1221 displaced_step_dump_bytes (struct ui_file
*file
,
1222 const gdb_byte
*buf
,
1227 for (i
= 0; i
< len
; i
++)
1228 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1229 fputs_unfiltered ("\n", file
);
1232 /* Prepare to single-step, using displaced stepping.
1234 Note that we cannot use displaced stepping when we have a signal to
1235 deliver. If we have a signal to deliver and an instruction to step
1236 over, then after the step, there will be no indication from the
1237 target whether the thread entered a signal handler or ignored the
1238 signal and stepped over the instruction successfully --- both cases
1239 result in a simple SIGTRAP. In the first case we mustn't do a
1240 fixup, and in the second case we must --- but we can't tell which.
1241 Comments in the code for 'random signals' in handle_inferior_event
1242 explain how we handle this case instead.
1244 Returns 1 if preparing was successful -- this thread is going to be
1245 stepped now; or 0 if displaced stepping this thread got queued. */
1247 displaced_step_prepare (ptid_t ptid
)
1249 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1250 struct regcache
*regcache
= get_thread_regcache (ptid
);
1251 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1252 CORE_ADDR original
, copy
;
1254 struct displaced_step_closure
*closure
;
1255 struct displaced_step_inferior_state
*displaced
;
1257 /* We should never reach this function if the architecture does not
1258 support displaced stepping. */
1259 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1261 /* We have to displaced step one thread at a time, as we only have
1262 access to a single scratch space per inferior. */
1264 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1266 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1268 /* Already waiting for a displaced step to finish. Defer this
1269 request and place in queue. */
1270 struct displaced_step_request
*req
, *new_req
;
1272 if (debug_displaced
)
1273 fprintf_unfiltered (gdb_stdlog
,
1274 "displaced: defering step of %s\n",
1275 target_pid_to_str (ptid
));
1277 new_req
= xmalloc (sizeof (*new_req
));
1278 new_req
->ptid
= ptid
;
1279 new_req
->next
= NULL
;
1281 if (displaced
->step_request_queue
)
1283 for (req
= displaced
->step_request_queue
;
1287 req
->next
= new_req
;
1290 displaced
->step_request_queue
= new_req
;
1296 if (debug_displaced
)
1297 fprintf_unfiltered (gdb_stdlog
,
1298 "displaced: stepping %s now\n",
1299 target_pid_to_str (ptid
));
1302 displaced_step_clear (displaced
);
1304 old_cleanups
= save_inferior_ptid ();
1305 inferior_ptid
= ptid
;
1307 original
= regcache_read_pc (regcache
);
1309 copy
= gdbarch_displaced_step_location (gdbarch
);
1310 len
= gdbarch_max_insn_length (gdbarch
);
1312 /* Save the original contents of the copy area. */
1313 displaced
->step_saved_copy
= xmalloc (len
);
1314 ignore_cleanups
= make_cleanup (free_current_contents
,
1315 &displaced
->step_saved_copy
);
1316 read_memory (copy
, displaced
->step_saved_copy
, len
);
1317 if (debug_displaced
)
1319 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1320 paddress (gdbarch
, copy
));
1321 displaced_step_dump_bytes (gdb_stdlog
,
1322 displaced
->step_saved_copy
,
1326 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1327 original
, copy
, regcache
);
1329 /* We don't support the fully-simulated case at present. */
1330 gdb_assert (closure
);
1332 /* Save the information we need to fix things up if the step
1334 displaced
->step_ptid
= ptid
;
1335 displaced
->step_gdbarch
= gdbarch
;
1336 displaced
->step_closure
= closure
;
1337 displaced
->step_original
= original
;
1338 displaced
->step_copy
= copy
;
1340 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1342 /* Resume execution at the copy. */
1343 regcache_write_pc (regcache
, copy
);
1345 discard_cleanups (ignore_cleanups
);
1347 do_cleanups (old_cleanups
);
1349 if (debug_displaced
)
1350 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1351 paddress (gdbarch
, copy
));
1357 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1358 const gdb_byte
*myaddr
, int len
)
1360 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1362 inferior_ptid
= ptid
;
1363 write_memory (memaddr
, myaddr
, len
);
1364 do_cleanups (ptid_cleanup
);
1367 /* Restore the contents of the copy area for thread PTID. */
1370 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1373 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1375 write_memory_ptid (ptid
, displaced
->step_copy
,
1376 displaced
->step_saved_copy
, len
);
1377 if (debug_displaced
)
1378 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1379 target_pid_to_str (ptid
),
1380 paddress (displaced
->step_gdbarch
,
1381 displaced
->step_copy
));
1385 displaced_step_fixup (ptid_t event_ptid
, enum target_signal signal
)
1387 struct cleanup
*old_cleanups
;
1388 struct displaced_step_inferior_state
*displaced
1389 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1391 /* Was any thread of this process doing a displaced step? */
1392 if (displaced
== NULL
)
1395 /* Was this event for the pid we displaced? */
1396 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1397 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1400 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1402 displaced_step_restore (displaced
, displaced
->step_ptid
);
1404 /* Did the instruction complete successfully? */
1405 if (signal
== TARGET_SIGNAL_TRAP
)
1407 /* Fix up the resulting state. */
1408 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1409 displaced
->step_closure
,
1410 displaced
->step_original
,
1411 displaced
->step_copy
,
1412 get_thread_regcache (displaced
->step_ptid
));
1416 /* Since the instruction didn't complete, all we can do is
1418 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1419 CORE_ADDR pc
= regcache_read_pc (regcache
);
1421 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1422 regcache_write_pc (regcache
, pc
);
1425 do_cleanups (old_cleanups
);
1427 displaced
->step_ptid
= null_ptid
;
1429 /* Are there any pending displaced stepping requests? If so, run
1430 one now. Leave the state object around, since we're likely to
1431 need it again soon. */
1432 while (displaced
->step_request_queue
)
1434 struct displaced_step_request
*head
;
1436 struct regcache
*regcache
;
1437 struct gdbarch
*gdbarch
;
1438 CORE_ADDR actual_pc
;
1439 struct address_space
*aspace
;
1441 head
= displaced
->step_request_queue
;
1443 displaced
->step_request_queue
= head
->next
;
1446 context_switch (ptid
);
1448 regcache
= get_thread_regcache (ptid
);
1449 actual_pc
= regcache_read_pc (regcache
);
1450 aspace
= get_regcache_aspace (regcache
);
1452 if (breakpoint_here_p (aspace
, actual_pc
))
1454 if (debug_displaced
)
1455 fprintf_unfiltered (gdb_stdlog
,
1456 "displaced: stepping queued %s now\n",
1457 target_pid_to_str (ptid
));
1459 displaced_step_prepare (ptid
);
1461 gdbarch
= get_regcache_arch (regcache
);
1463 if (debug_displaced
)
1465 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
1468 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1469 paddress (gdbarch
, actual_pc
));
1470 read_memory (actual_pc
, buf
, sizeof (buf
));
1471 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1474 if (gdbarch_displaced_step_hw_singlestep (gdbarch
,
1475 displaced
->step_closure
))
1476 target_resume (ptid
, 1, TARGET_SIGNAL_0
);
1478 target_resume (ptid
, 0, TARGET_SIGNAL_0
);
1480 /* Done, we're stepping a thread. */
1486 struct thread_info
*tp
= inferior_thread ();
1488 /* The breakpoint we were sitting under has since been
1490 tp
->control
.trap_expected
= 0;
1492 /* Go back to what we were trying to do. */
1493 step
= currently_stepping (tp
);
1495 if (debug_displaced
)
1496 fprintf_unfiltered (gdb_stdlog
,
1497 "breakpoint is gone %s: step(%d)\n",
1498 target_pid_to_str (tp
->ptid
), step
);
1500 target_resume (ptid
, step
, TARGET_SIGNAL_0
);
1501 tp
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
1503 /* This request was discarded. See if there's any other
1504 thread waiting for its turn. */
1509 /* Update global variables holding ptids to hold NEW_PTID if they were
1510 holding OLD_PTID. */
1512 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1514 struct displaced_step_request
*it
;
1515 struct displaced_step_inferior_state
*displaced
;
1517 if (ptid_equal (inferior_ptid
, old_ptid
))
1518 inferior_ptid
= new_ptid
;
1520 if (ptid_equal (singlestep_ptid
, old_ptid
))
1521 singlestep_ptid
= new_ptid
;
1523 if (ptid_equal (deferred_step_ptid
, old_ptid
))
1524 deferred_step_ptid
= new_ptid
;
1526 for (displaced
= displaced_step_inferior_states
;
1528 displaced
= displaced
->next
)
1530 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
1531 displaced
->step_ptid
= new_ptid
;
1533 for (it
= displaced
->step_request_queue
; it
; it
= it
->next
)
1534 if (ptid_equal (it
->ptid
, old_ptid
))
1535 it
->ptid
= new_ptid
;
1542 /* Things to clean up if we QUIT out of resume (). */
1544 resume_cleanups (void *ignore
)
1549 static const char schedlock_off
[] = "off";
1550 static const char schedlock_on
[] = "on";
1551 static const char schedlock_step
[] = "step";
1552 static const char *scheduler_enums
[] = {
1558 static const char *scheduler_mode
= schedlock_off
;
1560 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1561 struct cmd_list_element
*c
, const char *value
)
1563 fprintf_filtered (file
,
1564 _("Mode for locking scheduler "
1565 "during execution is \"%s\".\n"),
1570 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1572 if (!target_can_lock_scheduler
)
1574 scheduler_mode
= schedlock_off
;
1575 error (_("Target '%s' cannot support this command."), target_shortname
);
1579 /* True if execution commands resume all threads of all processes by
1580 default; otherwise, resume only threads of the current inferior
1582 int sched_multi
= 0;
1584 /* Try to setup for software single stepping over the specified location.
1585 Return 1 if target_resume() should use hardware single step.
1587 GDBARCH the current gdbarch.
1588 PC the location to step over. */
1591 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1595 if (execution_direction
== EXEC_FORWARD
1596 && gdbarch_software_single_step_p (gdbarch
)
1597 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1600 /* Do not pull these breakpoints until after a `wait' in
1601 `wait_for_inferior'. */
1602 singlestep_breakpoints_inserted_p
= 1;
1603 singlestep_ptid
= inferior_ptid
;
1609 /* Return a ptid representing the set of threads that we will proceed,
1610 in the perspective of the user/frontend. We may actually resume
1611 fewer threads at first, e.g., if a thread is stopped at a
1612 breakpoint that needs stepping-off, but that should not be visible
1613 to the user/frontend, and neither should the frontend/user be
1614 allowed to proceed any of the threads that happen to be stopped for
1615 internal run control handling, if a previous command wanted them
1619 user_visible_resume_ptid (int step
)
1621 /* By default, resume all threads of all processes. */
1622 ptid_t resume_ptid
= RESUME_ALL
;
1624 /* Maybe resume only all threads of the current process. */
1625 if (!sched_multi
&& target_supports_multi_process ())
1627 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
1630 /* Maybe resume a single thread after all. */
1633 /* With non-stop mode on, threads are always handled
1635 resume_ptid
= inferior_ptid
;
1637 else if ((scheduler_mode
== schedlock_on
)
1638 || (scheduler_mode
== schedlock_step
1639 && (step
|| singlestep_breakpoints_inserted_p
)))
1641 /* User-settable 'scheduler' mode requires solo thread resume. */
1642 resume_ptid
= inferior_ptid
;
1648 /* Resume the inferior, but allow a QUIT. This is useful if the user
1649 wants to interrupt some lengthy single-stepping operation
1650 (for child processes, the SIGINT goes to the inferior, and so
1651 we get a SIGINT random_signal, but for remote debugging and perhaps
1652 other targets, that's not true).
1654 STEP nonzero if we should step (zero to continue instead).
1655 SIG is the signal to give the inferior (zero for none). */
1657 resume (int step
, enum target_signal sig
)
1659 int should_resume
= 1;
1660 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
1661 struct regcache
*regcache
= get_current_regcache ();
1662 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1663 struct thread_info
*tp
= inferior_thread ();
1664 CORE_ADDR pc
= regcache_read_pc (regcache
);
1665 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1669 if (current_inferior ()->waiting_for_vfork_done
)
1671 /* Don't try to single-step a vfork parent that is waiting for
1672 the child to get out of the shared memory region (by exec'ing
1673 or exiting). This is particularly important on software
1674 single-step archs, as the child process would trip on the
1675 software single step breakpoint inserted for the parent
1676 process. Since the parent will not actually execute any
1677 instruction until the child is out of the shared region (such
1678 are vfork's semantics), it is safe to simply continue it.
1679 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
1680 the parent, and tell it to `keep_going', which automatically
1681 re-sets it stepping. */
1683 fprintf_unfiltered (gdb_stdlog
,
1684 "infrun: resume : clear step\n");
1689 fprintf_unfiltered (gdb_stdlog
,
1690 "infrun: resume (step=%d, signal=%d), "
1691 "trap_expected=%d, current thread [%s] at %s\n",
1692 step
, sig
, tp
->control
.trap_expected
,
1693 target_pid_to_str (inferior_ptid
),
1694 paddress (gdbarch
, pc
));
1696 /* Normally, by the time we reach `resume', the breakpoints are either
1697 removed or inserted, as appropriate. The exception is if we're sitting
1698 at a permanent breakpoint; we need to step over it, but permanent
1699 breakpoints can't be removed. So we have to test for it here. */
1700 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
1702 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
1703 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
1706 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1707 how to step past a permanent breakpoint on this architecture. Try using\n\
1708 a command like `return' or `jump' to continue execution."));
1711 /* If enabled, step over breakpoints by executing a copy of the
1712 instruction at a different address.
1714 We can't use displaced stepping when we have a signal to deliver;
1715 the comments for displaced_step_prepare explain why. The
1716 comments in the handle_inferior event for dealing with 'random
1717 signals' explain what we do instead.
1719 We can't use displaced stepping when we are waiting for vfork_done
1720 event, displaced stepping breaks the vfork child similarly as single
1721 step software breakpoint. */
1722 if (use_displaced_stepping (gdbarch
)
1723 && (tp
->control
.trap_expected
1724 || (step
&& gdbarch_software_single_step_p (gdbarch
)))
1725 && sig
== TARGET_SIGNAL_0
1726 && !current_inferior ()->waiting_for_vfork_done
)
1728 struct displaced_step_inferior_state
*displaced
;
1730 if (!displaced_step_prepare (inferior_ptid
))
1732 /* Got placed in displaced stepping queue. Will be resumed
1733 later when all the currently queued displaced stepping
1734 requests finish. The thread is not executing at this point,
1735 and the call to set_executing will be made later. But we
1736 need to call set_running here, since from frontend point of view,
1737 the thread is running. */
1738 set_running (inferior_ptid
, 1);
1739 discard_cleanups (old_cleanups
);
1743 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1744 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
1745 displaced
->step_closure
);
1748 /* Do we need to do it the hard way, w/temp breakpoints? */
1750 step
= maybe_software_singlestep (gdbarch
, pc
);
1752 /* Currently, our software single-step implementation leads to different
1753 results than hardware single-stepping in one situation: when stepping
1754 into delivering a signal which has an associated signal handler,
1755 hardware single-step will stop at the first instruction of the handler,
1756 while software single-step will simply skip execution of the handler.
1758 For now, this difference in behavior is accepted since there is no
1759 easy way to actually implement single-stepping into a signal handler
1760 without kernel support.
1762 However, there is one scenario where this difference leads to follow-on
1763 problems: if we're stepping off a breakpoint by removing all breakpoints
1764 and then single-stepping. In this case, the software single-step
1765 behavior means that even if there is a *breakpoint* in the signal
1766 handler, GDB still would not stop.
1768 Fortunately, we can at least fix this particular issue. We detect
1769 here the case where we are about to deliver a signal while software
1770 single-stepping with breakpoints removed. In this situation, we
1771 revert the decisions to remove all breakpoints and insert single-
1772 step breakpoints, and instead we install a step-resume breakpoint
1773 at the current address, deliver the signal without stepping, and
1774 once we arrive back at the step-resume breakpoint, actually step
1775 over the breakpoint we originally wanted to step over. */
1776 if (singlestep_breakpoints_inserted_p
1777 && tp
->control
.trap_expected
&& sig
!= TARGET_SIGNAL_0
)
1779 /* If we have nested signals or a pending signal is delivered
1780 immediately after a handler returns, might might already have
1781 a step-resume breakpoint set on the earlier handler. We cannot
1782 set another step-resume breakpoint; just continue on until the
1783 original breakpoint is hit. */
1784 if (tp
->control
.step_resume_breakpoint
== NULL
)
1786 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
1787 tp
->step_after_step_resume_breakpoint
= 1;
1790 remove_single_step_breakpoints ();
1791 singlestep_breakpoints_inserted_p
= 0;
1793 insert_breakpoints ();
1794 tp
->control
.trap_expected
= 0;
1801 /* If STEP is set, it's a request to use hardware stepping
1802 facilities. But in that case, we should never
1803 use singlestep breakpoint. */
1804 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1806 /* Decide the set of threads to ask the target to resume. Start
1807 by assuming everything will be resumed, than narrow the set
1808 by applying increasingly restricting conditions. */
1809 resume_ptid
= user_visible_resume_ptid (step
);
1811 /* Maybe resume a single thread after all. */
1812 if (singlestep_breakpoints_inserted_p
1813 && stepping_past_singlestep_breakpoint
)
1815 /* The situation here is as follows. In thread T1 we wanted to
1816 single-step. Lacking hardware single-stepping we've
1817 set breakpoint at the PC of the next instruction -- call it
1818 P. After resuming, we've hit that breakpoint in thread T2.
1819 Now we've removed original breakpoint, inserted breakpoint
1820 at P+1, and try to step to advance T2 past breakpoint.
1821 We need to step only T2, as if T1 is allowed to freely run,
1822 it can run past P, and if other threads are allowed to run,
1823 they can hit breakpoint at P+1, and nested hits of single-step
1824 breakpoints is not something we'd want -- that's complicated
1825 to support, and has no value. */
1826 resume_ptid
= inferior_ptid
;
1828 else if ((step
|| singlestep_breakpoints_inserted_p
)
1829 && tp
->control
.trap_expected
)
1831 /* We're allowing a thread to run past a breakpoint it has
1832 hit, by single-stepping the thread with the breakpoint
1833 removed. In which case, we need to single-step only this
1834 thread, and keep others stopped, as they can miss this
1835 breakpoint if allowed to run.
1837 The current code actually removes all breakpoints when
1838 doing this, not just the one being stepped over, so if we
1839 let other threads run, we can actually miss any
1840 breakpoint, not just the one at PC. */
1841 resume_ptid
= inferior_ptid
;
1844 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1846 /* Most targets can step a breakpoint instruction, thus
1847 executing it normally. But if this one cannot, just
1848 continue and we will hit it anyway. */
1849 if (step
&& breakpoint_inserted_here_p (aspace
, pc
))
1854 && use_displaced_stepping (gdbarch
)
1855 && tp
->control
.trap_expected
)
1857 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1858 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
1859 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1862 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1863 paddress (resume_gdbarch
, actual_pc
));
1864 read_memory (actual_pc
, buf
, sizeof (buf
));
1865 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1868 /* Install inferior's terminal modes. */
1869 target_terminal_inferior ();
1871 /* Avoid confusing the next resume, if the next stop/resume
1872 happens to apply to another thread. */
1873 tp
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
1875 /* Advise target which signals may be handled silently. If we have
1876 removed breakpoints because we are stepping over one (which can
1877 happen only if we are not using displaced stepping), we need to
1878 receive all signals to avoid accidentally skipping a breakpoint
1879 during execution of a signal handler. */
1880 if ((step
|| singlestep_breakpoints_inserted_p
)
1881 && tp
->control
.trap_expected
1882 && !use_displaced_stepping (gdbarch
))
1883 target_pass_signals (0, NULL
);
1885 target_pass_signals ((int) TARGET_SIGNAL_LAST
, signal_pass
);
1887 target_resume (resume_ptid
, step
, sig
);
1890 discard_cleanups (old_cleanups
);
1895 /* Clear out all variables saying what to do when inferior is continued.
1896 First do this, then set the ones you want, then call `proceed'. */
1899 clear_proceed_status_thread (struct thread_info
*tp
)
1902 fprintf_unfiltered (gdb_stdlog
,
1903 "infrun: clear_proceed_status_thread (%s)\n",
1904 target_pid_to_str (tp
->ptid
));
1906 tp
->control
.trap_expected
= 0;
1907 tp
->control
.step_range_start
= 0;
1908 tp
->control
.step_range_end
= 0;
1909 tp
->control
.step_frame_id
= null_frame_id
;
1910 tp
->control
.step_stack_frame_id
= null_frame_id
;
1911 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1912 tp
->stop_requested
= 0;
1914 tp
->control
.stop_step
= 0;
1916 tp
->control
.proceed_to_finish
= 0;
1918 /* Discard any remaining commands or status from previous stop. */
1919 bpstat_clear (&tp
->control
.stop_bpstat
);
1923 clear_proceed_status_callback (struct thread_info
*tp
, void *data
)
1925 if (is_exited (tp
->ptid
))
1928 clear_proceed_status_thread (tp
);
1933 clear_proceed_status (void)
1937 /* In all-stop mode, delete the per-thread status of all
1938 threads, even if inferior_ptid is null_ptid, there may be
1939 threads on the list. E.g., we may be launching a new
1940 process, while selecting the executable. */
1941 iterate_over_threads (clear_proceed_status_callback
, NULL
);
1944 if (!ptid_equal (inferior_ptid
, null_ptid
))
1946 struct inferior
*inferior
;
1950 /* If in non-stop mode, only delete the per-thread status of
1951 the current thread. */
1952 clear_proceed_status_thread (inferior_thread ());
1955 inferior
= current_inferior ();
1956 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
1959 stop_after_trap
= 0;
1961 observer_notify_about_to_proceed ();
1965 regcache_xfree (stop_registers
);
1966 stop_registers
= NULL
;
1970 /* Check the current thread against the thread that reported the most recent
1971 event. If a step-over is required return TRUE and set the current thread
1972 to the old thread. Otherwise return FALSE.
1974 This should be suitable for any targets that support threads. */
1977 prepare_to_proceed (int step
)
1980 struct target_waitstatus wait_status
;
1981 int schedlock_enabled
;
1983 /* With non-stop mode on, threads are always handled individually. */
1984 gdb_assert (! non_stop
);
1986 /* Get the last target status returned by target_wait(). */
1987 get_last_target_status (&wait_ptid
, &wait_status
);
1989 /* Make sure we were stopped at a breakpoint. */
1990 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
1991 || (wait_status
.value
.sig
!= TARGET_SIGNAL_TRAP
1992 && wait_status
.value
.sig
!= TARGET_SIGNAL_ILL
1993 && wait_status
.value
.sig
!= TARGET_SIGNAL_SEGV
1994 && wait_status
.value
.sig
!= TARGET_SIGNAL_EMT
))
1999 schedlock_enabled
= (scheduler_mode
== schedlock_on
2000 || (scheduler_mode
== schedlock_step
2003 /* Don't switch over to WAIT_PTID if scheduler locking is on. */
2004 if (schedlock_enabled
)
2007 /* Don't switch over if we're about to resume some other process
2008 other than WAIT_PTID's, and schedule-multiple is off. */
2010 && ptid_get_pid (wait_ptid
) != ptid_get_pid (inferior_ptid
))
2013 /* Switched over from WAIT_PID. */
2014 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
2015 && !ptid_equal (inferior_ptid
, wait_ptid
))
2017 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
2019 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2020 regcache_read_pc (regcache
)))
2022 /* If stepping, remember current thread to switch back to. */
2024 deferred_step_ptid
= inferior_ptid
;
2026 /* Switch back to WAIT_PID thread. */
2027 switch_to_thread (wait_ptid
);
2030 fprintf_unfiltered (gdb_stdlog
,
2031 "infrun: prepare_to_proceed (step=%d), "
2032 "switched to [%s]\n",
2033 step
, target_pid_to_str (inferior_ptid
));
2035 /* We return 1 to indicate that there is a breakpoint here,
2036 so we need to step over it before continuing to avoid
2037 hitting it straight away. */
2045 /* Basic routine for continuing the program in various fashions.
2047 ADDR is the address to resume at, or -1 for resume where stopped.
2048 SIGGNAL is the signal to give it, or 0 for none,
2049 or -1 for act according to how it stopped.
2050 STEP is nonzero if should trap after one instruction.
2051 -1 means return after that and print nothing.
2052 You should probably set various step_... variables
2053 before calling here, if you are stepping.
2055 You should call clear_proceed_status before calling proceed. */
2058 proceed (CORE_ADDR addr
, enum target_signal siggnal
, int step
)
2060 struct regcache
*regcache
;
2061 struct gdbarch
*gdbarch
;
2062 struct thread_info
*tp
;
2064 struct address_space
*aspace
;
2067 /* If we're stopped at a fork/vfork, follow the branch set by the
2068 "set follow-fork-mode" command; otherwise, we'll just proceed
2069 resuming the current thread. */
2070 if (!follow_fork ())
2072 /* The target for some reason decided not to resume. */
2074 if (target_can_async_p ())
2075 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2079 /* We'll update this if & when we switch to a new thread. */
2080 previous_inferior_ptid
= inferior_ptid
;
2082 regcache
= get_current_regcache ();
2083 gdbarch
= get_regcache_arch (regcache
);
2084 aspace
= get_regcache_aspace (regcache
);
2085 pc
= regcache_read_pc (regcache
);
2088 step_start_function
= find_pc_function (pc
);
2090 stop_after_trap
= 1;
2092 if (addr
== (CORE_ADDR
) -1)
2094 if (pc
== stop_pc
&& breakpoint_here_p (aspace
, pc
)
2095 && execution_direction
!= EXEC_REVERSE
)
2096 /* There is a breakpoint at the address we will resume at,
2097 step one instruction before inserting breakpoints so that
2098 we do not stop right away (and report a second hit at this
2101 Note, we don't do this in reverse, because we won't
2102 actually be executing the breakpoint insn anyway.
2103 We'll be (un-)executing the previous instruction. */
2106 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2107 && gdbarch_single_step_through_delay (gdbarch
,
2108 get_current_frame ()))
2109 /* We stepped onto an instruction that needs to be stepped
2110 again before re-inserting the breakpoint, do so. */
2115 regcache_write_pc (regcache
, addr
);
2119 fprintf_unfiltered (gdb_stdlog
,
2120 "infrun: proceed (addr=%s, signal=%d, step=%d)\n",
2121 paddress (gdbarch
, addr
), siggnal
, step
);
2124 /* In non-stop, each thread is handled individually. The context
2125 must already be set to the right thread here. */
2129 /* In a multi-threaded task we may select another thread and
2130 then continue or step.
2132 But if the old thread was stopped at a breakpoint, it will
2133 immediately cause another breakpoint stop without any
2134 execution (i.e. it will report a breakpoint hit incorrectly).
2135 So we must step over it first.
2137 prepare_to_proceed checks the current thread against the
2138 thread that reported the most recent event. If a step-over
2139 is required it returns TRUE and sets the current thread to
2141 if (prepare_to_proceed (step
))
2145 /* prepare_to_proceed may change the current thread. */
2146 tp
= inferior_thread ();
2150 tp
->control
.trap_expected
= 1;
2151 /* If displaced stepping is enabled, we can step over the
2152 breakpoint without hitting it, so leave all breakpoints
2153 inserted. Otherwise we need to disable all breakpoints, step
2154 one instruction, and then re-add them when that step is
2156 if (!use_displaced_stepping (gdbarch
))
2157 remove_breakpoints ();
2160 /* We can insert breakpoints if we're not trying to step over one,
2161 or if we are stepping over one but we're using displaced stepping
2163 if (! tp
->control
.trap_expected
|| use_displaced_stepping (gdbarch
))
2164 insert_breakpoints ();
2168 /* Pass the last stop signal to the thread we're resuming,
2169 irrespective of whether the current thread is the thread that
2170 got the last event or not. This was historically GDB's
2171 behaviour before keeping a stop_signal per thread. */
2173 struct thread_info
*last_thread
;
2175 struct target_waitstatus last_status
;
2177 get_last_target_status (&last_ptid
, &last_status
);
2178 if (!ptid_equal (inferior_ptid
, last_ptid
)
2179 && !ptid_equal (last_ptid
, null_ptid
)
2180 && !ptid_equal (last_ptid
, minus_one_ptid
))
2182 last_thread
= find_thread_ptid (last_ptid
);
2185 tp
->suspend
.stop_signal
= last_thread
->suspend
.stop_signal
;
2186 last_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
2191 if (siggnal
!= TARGET_SIGNAL_DEFAULT
)
2192 tp
->suspend
.stop_signal
= siggnal
;
2193 /* If this signal should not be seen by program,
2194 give it zero. Used for debugging signals. */
2195 else if (!signal_program
[tp
->suspend
.stop_signal
])
2196 tp
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
2198 annotate_starting ();
2200 /* Make sure that output from GDB appears before output from the
2202 gdb_flush (gdb_stdout
);
2204 /* Refresh prev_pc value just prior to resuming. This used to be
2205 done in stop_stepping, however, setting prev_pc there did not handle
2206 scenarios such as inferior function calls or returning from
2207 a function via the return command. In those cases, the prev_pc
2208 value was not set properly for subsequent commands. The prev_pc value
2209 is used to initialize the starting line number in the ecs. With an
2210 invalid value, the gdb next command ends up stopping at the position
2211 represented by the next line table entry past our start position.
2212 On platforms that generate one line table entry per line, this
2213 is not a problem. However, on the ia64, the compiler generates
2214 extraneous line table entries that do not increase the line number.
2215 When we issue the gdb next command on the ia64 after an inferior call
2216 or a return command, we often end up a few instructions forward, still
2217 within the original line we started.
2219 An attempt was made to refresh the prev_pc at the same time the
2220 execution_control_state is initialized (for instance, just before
2221 waiting for an inferior event). But this approach did not work
2222 because of platforms that use ptrace, where the pc register cannot
2223 be read unless the inferior is stopped. At that point, we are not
2224 guaranteed the inferior is stopped and so the regcache_read_pc() call
2225 can fail. Setting the prev_pc value here ensures the value is updated
2226 correctly when the inferior is stopped. */
2227 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2229 /* Fill in with reasonable starting values. */
2230 init_thread_stepping_state (tp
);
2232 /* Reset to normal state. */
2233 init_infwait_state ();
2235 /* Resume inferior. */
2236 resume (oneproc
|| step
|| bpstat_should_step (), tp
->suspend
.stop_signal
);
2238 /* Wait for it to stop (if not standalone)
2239 and in any case decode why it stopped, and act accordingly. */
2240 /* Do this only if we are not using the event loop, or if the target
2241 does not support asynchronous execution. */
2242 if (!target_can_async_p ())
2244 wait_for_inferior ();
2250 /* Start remote-debugging of a machine over a serial link. */
2253 start_remote (int from_tty
)
2255 struct inferior
*inferior
;
2257 inferior
= current_inferior ();
2258 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
2260 /* Always go on waiting for the target, regardless of the mode. */
2261 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2262 indicate to wait_for_inferior that a target should timeout if
2263 nothing is returned (instead of just blocking). Because of this,
2264 targets expecting an immediate response need to, internally, set
2265 things up so that the target_wait() is forced to eventually
2267 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2268 differentiate to its caller what the state of the target is after
2269 the initial open has been performed. Here we're assuming that
2270 the target has stopped. It should be possible to eventually have
2271 target_open() return to the caller an indication that the target
2272 is currently running and GDB state should be set to the same as
2273 for an async run. */
2274 wait_for_inferior ();
2276 /* Now that the inferior has stopped, do any bookkeeping like
2277 loading shared libraries. We want to do this before normal_stop,
2278 so that the displayed frame is up to date. */
2279 post_create_inferior (¤t_target
, from_tty
);
2284 /* Initialize static vars when a new inferior begins. */
2287 init_wait_for_inferior (void)
2289 /* These are meaningless until the first time through wait_for_inferior. */
2291 breakpoint_init_inferior (inf_starting
);
2293 clear_proceed_status ();
2295 stepping_past_singlestep_breakpoint
= 0;
2296 deferred_step_ptid
= null_ptid
;
2298 target_last_wait_ptid
= minus_one_ptid
;
2300 previous_inferior_ptid
= inferior_ptid
;
2301 init_infwait_state ();
2303 /* Discard any skipped inlined frames. */
2304 clear_inline_frame_state (minus_one_ptid
);
2308 /* This enum encodes possible reasons for doing a target_wait, so that
2309 wfi can call target_wait in one place. (Ultimately the call will be
2310 moved out of the infinite loop entirely.) */
2314 infwait_normal_state
,
2315 infwait_thread_hop_state
,
2316 infwait_step_watch_state
,
2317 infwait_nonstep_watch_state
2320 /* The PTID we'll do a target_wait on.*/
2323 /* Current inferior wait state. */
2324 enum infwait_states infwait_state
;
2326 /* Data to be passed around while handling an event. This data is
2327 discarded between events. */
2328 struct execution_control_state
2331 /* The thread that got the event, if this was a thread event; NULL
2333 struct thread_info
*event_thread
;
2335 struct target_waitstatus ws
;
2337 int stop_func_filled_in
;
2338 CORE_ADDR stop_func_start
;
2339 CORE_ADDR stop_func_end
;
2340 char *stop_func_name
;
2341 int new_thread_event
;
2345 static void handle_inferior_event (struct execution_control_state
*ecs
);
2347 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2348 struct execution_control_state
*ecs
);
2349 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2350 struct execution_control_state
*ecs
);
2351 static void check_exception_resume (struct execution_control_state
*,
2352 struct frame_info
*, struct symbol
*);
2354 static void stop_stepping (struct execution_control_state
*ecs
);
2355 static void prepare_to_wait (struct execution_control_state
*ecs
);
2356 static void keep_going (struct execution_control_state
*ecs
);
2358 /* Callback for iterate over threads. If the thread is stopped, but
2359 the user/frontend doesn't know about that yet, go through
2360 normal_stop, as if the thread had just stopped now. ARG points at
2361 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2362 ptid_is_pid(PTID) is true, applies to all threads of the process
2363 pointed at by PTID. Otherwise, apply only to the thread pointed by
2367 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2369 ptid_t ptid
= * (ptid_t
*) arg
;
2371 if ((ptid_equal (info
->ptid
, ptid
)
2372 || ptid_equal (minus_one_ptid
, ptid
)
2373 || (ptid_is_pid (ptid
)
2374 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2375 && is_running (info
->ptid
)
2376 && !is_executing (info
->ptid
))
2378 struct cleanup
*old_chain
;
2379 struct execution_control_state ecss
;
2380 struct execution_control_state
*ecs
= &ecss
;
2382 memset (ecs
, 0, sizeof (*ecs
));
2384 old_chain
= make_cleanup_restore_current_thread ();
2386 switch_to_thread (info
->ptid
);
2388 /* Go through handle_inferior_event/normal_stop, so we always
2389 have consistent output as if the stop event had been
2391 ecs
->ptid
= info
->ptid
;
2392 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2393 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2394 ecs
->ws
.value
.sig
= TARGET_SIGNAL_0
;
2396 handle_inferior_event (ecs
);
2398 if (!ecs
->wait_some_more
)
2400 struct thread_info
*tp
;
2404 /* Finish off the continuations. */
2405 tp
= inferior_thread ();
2406 do_all_intermediate_continuations_thread (tp
, 1);
2407 do_all_continuations_thread (tp
, 1);
2410 do_cleanups (old_chain
);
2416 /* This function is attached as a "thread_stop_requested" observer.
2417 Cleanup local state that assumed the PTID was to be resumed, and
2418 report the stop to the frontend. */
2421 infrun_thread_stop_requested (ptid_t ptid
)
2423 struct displaced_step_inferior_state
*displaced
;
2425 /* PTID was requested to stop. Remove it from the displaced
2426 stepping queue, so we don't try to resume it automatically. */
2428 for (displaced
= displaced_step_inferior_states
;
2430 displaced
= displaced
->next
)
2432 struct displaced_step_request
*it
, **prev_next_p
;
2434 it
= displaced
->step_request_queue
;
2435 prev_next_p
= &displaced
->step_request_queue
;
2438 if (ptid_match (it
->ptid
, ptid
))
2440 *prev_next_p
= it
->next
;
2446 prev_next_p
= &it
->next
;
2453 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2457 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2459 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2460 nullify_last_target_wait_ptid ();
2463 /* Callback for iterate_over_threads. */
2466 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
2468 if (is_exited (info
->ptid
))
2471 delete_step_resume_breakpoint (info
);
2472 delete_exception_resume_breakpoint (info
);
2476 /* In all-stop, delete the step resume breakpoint of any thread that
2477 had one. In non-stop, delete the step resume breakpoint of the
2478 thread that just stopped. */
2481 delete_step_thread_step_resume_breakpoint (void)
2483 if (!target_has_execution
2484 || ptid_equal (inferior_ptid
, null_ptid
))
2485 /* If the inferior has exited, we have already deleted the step
2486 resume breakpoints out of GDB's lists. */
2491 /* If in non-stop mode, only delete the step-resume or
2492 longjmp-resume breakpoint of the thread that just stopped
2494 struct thread_info
*tp
= inferior_thread ();
2496 delete_step_resume_breakpoint (tp
);
2497 delete_exception_resume_breakpoint (tp
);
2500 /* In all-stop mode, delete all step-resume and longjmp-resume
2501 breakpoints of any thread that had them. */
2502 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
2505 /* A cleanup wrapper. */
2508 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
2510 delete_step_thread_step_resume_breakpoint ();
2513 /* Pretty print the results of target_wait, for debugging purposes. */
2516 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
2517 const struct target_waitstatus
*ws
)
2519 char *status_string
= target_waitstatus_to_string (ws
);
2520 struct ui_file
*tmp_stream
= mem_fileopen ();
2523 /* The text is split over several lines because it was getting too long.
2524 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2525 output as a unit; we want only one timestamp printed if debug_timestamp
2528 fprintf_unfiltered (tmp_stream
,
2529 "infrun: target_wait (%d", PIDGET (waiton_ptid
));
2530 if (PIDGET (waiton_ptid
) != -1)
2531 fprintf_unfiltered (tmp_stream
,
2532 " [%s]", target_pid_to_str (waiton_ptid
));
2533 fprintf_unfiltered (tmp_stream
, ", status) =\n");
2534 fprintf_unfiltered (tmp_stream
,
2535 "infrun: %d [%s],\n",
2536 PIDGET (result_ptid
), target_pid_to_str (result_ptid
));
2537 fprintf_unfiltered (tmp_stream
,
2541 text
= ui_file_xstrdup (tmp_stream
, NULL
);
2543 /* This uses %s in part to handle %'s in the text, but also to avoid
2544 a gcc error: the format attribute requires a string literal. */
2545 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
2547 xfree (status_string
);
2549 ui_file_delete (tmp_stream
);
2552 /* Prepare and stabilize the inferior for detaching it. E.g.,
2553 detaching while a thread is displaced stepping is a recipe for
2554 crashing it, as nothing would readjust the PC out of the scratch
2558 prepare_for_detach (void)
2560 struct inferior
*inf
= current_inferior ();
2561 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
2562 struct cleanup
*old_chain_1
;
2563 struct displaced_step_inferior_state
*displaced
;
2565 displaced
= get_displaced_stepping_state (inf
->pid
);
2567 /* Is any thread of this process displaced stepping? If not,
2568 there's nothing else to do. */
2569 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
2573 fprintf_unfiltered (gdb_stdlog
,
2574 "displaced-stepping in-process while detaching");
2576 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
2579 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
2581 struct cleanup
*old_chain_2
;
2582 struct execution_control_state ecss
;
2583 struct execution_control_state
*ecs
;
2586 memset (ecs
, 0, sizeof (*ecs
));
2588 overlay_cache_invalid
= 1;
2590 if (deprecated_target_wait_hook
)
2591 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
2593 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
2596 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
2598 /* If an error happens while handling the event, propagate GDB's
2599 knowledge of the executing state to the frontend/user running
2601 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
2604 /* In non-stop mode, each thread is handled individually.
2605 Switch early, so the global state is set correctly for this
2608 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2609 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2610 context_switch (ecs
->ptid
);
2612 /* Now figure out what to do with the result of the result. */
2613 handle_inferior_event (ecs
);
2615 /* No error, don't finish the state yet. */
2616 discard_cleanups (old_chain_2
);
2618 /* Breakpoints and watchpoints are not installed on the target
2619 at this point, and signals are passed directly to the
2620 inferior, so this must mean the process is gone. */
2621 if (!ecs
->wait_some_more
)
2623 discard_cleanups (old_chain_1
);
2624 error (_("Program exited while detaching"));
2628 discard_cleanups (old_chain_1
);
2631 /* Wait for control to return from inferior to debugger.
2633 If inferior gets a signal, we may decide to start it up again
2634 instead of returning. That is why there is a loop in this function.
2635 When this function actually returns it means the inferior
2636 should be left stopped and GDB should read more commands. */
2639 wait_for_inferior (void)
2641 struct cleanup
*old_cleanups
;
2642 struct execution_control_state ecss
;
2643 struct execution_control_state
*ecs
;
2647 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
2650 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
2653 memset (ecs
, 0, sizeof (*ecs
));
2657 struct cleanup
*old_chain
;
2659 overlay_cache_invalid
= 1;
2661 if (deprecated_target_wait_hook
)
2662 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
2664 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
2667 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2669 /* If an error happens while handling the event, propagate GDB's
2670 knowledge of the executing state to the frontend/user running
2672 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2674 if (ecs
->ws
.kind
== TARGET_WAITKIND_SYSCALL_ENTRY
2675 || ecs
->ws
.kind
== TARGET_WAITKIND_SYSCALL_RETURN
)
2676 ecs
->ws
.value
.syscall_number
= UNKNOWN_SYSCALL
;
2678 /* Now figure out what to do with the result of the result. */
2679 handle_inferior_event (ecs
);
2681 /* No error, don't finish the state yet. */
2682 discard_cleanups (old_chain
);
2684 if (!ecs
->wait_some_more
)
2688 do_cleanups (old_cleanups
);
2691 /* Asynchronous version of wait_for_inferior. It is called by the
2692 event loop whenever a change of state is detected on the file
2693 descriptor corresponding to the target. It can be called more than
2694 once to complete a single execution command. In such cases we need
2695 to keep the state in a global variable ECSS. If it is the last time
2696 that this function is called for a single execution command, then
2697 report to the user that the inferior has stopped, and do the
2698 necessary cleanups. */
2701 fetch_inferior_event (void *client_data
)
2703 struct execution_control_state ecss
;
2704 struct execution_control_state
*ecs
= &ecss
;
2705 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
2706 struct cleanup
*ts_old_chain
;
2707 int was_sync
= sync_execution
;
2710 memset (ecs
, 0, sizeof (*ecs
));
2712 /* We're handling a live event, so make sure we're doing live
2713 debugging. If we're looking at traceframes while the target is
2714 running, we're going to need to get back to that mode after
2715 handling the event. */
2718 make_cleanup_restore_current_traceframe ();
2719 set_current_traceframe (-1);
2723 /* In non-stop mode, the user/frontend should not notice a thread
2724 switch due to internal events. Make sure we reverse to the
2725 user selected thread and frame after handling the event and
2726 running any breakpoint commands. */
2727 make_cleanup_restore_current_thread ();
2729 overlay_cache_invalid
= 1;
2731 make_cleanup_restore_integer (&execution_direction
);
2732 execution_direction
= target_execution_direction ();
2734 if (deprecated_target_wait_hook
)
2736 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2738 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2741 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2744 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
2745 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2746 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2747 /* In non-stop mode, each thread is handled individually. Switch
2748 early, so the global state is set correctly for this
2750 context_switch (ecs
->ptid
);
2752 /* If an error happens while handling the event, propagate GDB's
2753 knowledge of the executing state to the frontend/user running
2756 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2758 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
2760 /* Get executed before make_cleanup_restore_current_thread above to apply
2761 still for the thread which has thrown the exception. */
2762 make_bpstat_clear_actions_cleanup ();
2764 /* Now figure out what to do with the result of the result. */
2765 handle_inferior_event (ecs
);
2767 if (!ecs
->wait_some_more
)
2769 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2771 delete_step_thread_step_resume_breakpoint ();
2773 /* We may not find an inferior if this was a process exit. */
2774 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
2777 if (target_has_execution
2778 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2779 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2780 && ecs
->event_thread
->step_multi
2781 && ecs
->event_thread
->control
.stop_step
)
2782 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
2785 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2790 /* No error, don't finish the thread states yet. */
2791 discard_cleanups (ts_old_chain
);
2793 /* Revert thread and frame. */
2794 do_cleanups (old_chain
);
2796 /* If the inferior was in sync execution mode, and now isn't,
2797 restore the prompt (a synchronous execution command has finished,
2798 and we're ready for input). */
2799 if (interpreter_async
&& was_sync
&& !sync_execution
)
2800 display_gdb_prompt (0);
2804 && exec_done_display_p
2805 && (ptid_equal (inferior_ptid
, null_ptid
)
2806 || !is_running (inferior_ptid
)))
2807 printf_unfiltered (_("completed.\n"));
2810 /* Record the frame and location we're currently stepping through. */
2812 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
2814 struct thread_info
*tp
= inferior_thread ();
2816 tp
->control
.step_frame_id
= get_frame_id (frame
);
2817 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
2819 tp
->current_symtab
= sal
.symtab
;
2820 tp
->current_line
= sal
.line
;
2823 /* Clear context switchable stepping state. */
2826 init_thread_stepping_state (struct thread_info
*tss
)
2828 tss
->stepping_over_breakpoint
= 0;
2829 tss
->step_after_step_resume_breakpoint
= 0;
2832 /* Return the cached copy of the last pid/waitstatus returned by
2833 target_wait()/deprecated_target_wait_hook(). The data is actually
2834 cached by handle_inferior_event(), which gets called immediately
2835 after target_wait()/deprecated_target_wait_hook(). */
2838 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
2840 *ptidp
= target_last_wait_ptid
;
2841 *status
= target_last_waitstatus
;
2845 nullify_last_target_wait_ptid (void)
2847 target_last_wait_ptid
= minus_one_ptid
;
2850 /* Switch thread contexts. */
2853 context_switch (ptid_t ptid
)
2857 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
2858 target_pid_to_str (inferior_ptid
));
2859 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
2860 target_pid_to_str (ptid
));
2863 switch_to_thread (ptid
);
2867 adjust_pc_after_break (struct execution_control_state
*ecs
)
2869 struct regcache
*regcache
;
2870 struct gdbarch
*gdbarch
;
2871 struct address_space
*aspace
;
2872 CORE_ADDR breakpoint_pc
;
2874 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2875 we aren't, just return.
2877 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2878 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2879 implemented by software breakpoints should be handled through the normal
2882 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2883 different signals (SIGILL or SIGEMT for instance), but it is less
2884 clear where the PC is pointing afterwards. It may not match
2885 gdbarch_decr_pc_after_break. I don't know any specific target that
2886 generates these signals at breakpoints (the code has been in GDB since at
2887 least 1992) so I can not guess how to handle them here.
2889 In earlier versions of GDB, a target with
2890 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2891 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2892 target with both of these set in GDB history, and it seems unlikely to be
2893 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2895 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
2898 if (ecs
->ws
.value
.sig
!= TARGET_SIGNAL_TRAP
)
2901 /* In reverse execution, when a breakpoint is hit, the instruction
2902 under it has already been de-executed. The reported PC always
2903 points at the breakpoint address, so adjusting it further would
2904 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2907 B1 0x08000000 : INSN1
2908 B2 0x08000001 : INSN2
2910 PC -> 0x08000003 : INSN4
2912 Say you're stopped at 0x08000003 as above. Reverse continuing
2913 from that point should hit B2 as below. Reading the PC when the
2914 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2915 been de-executed already.
2917 B1 0x08000000 : INSN1
2918 B2 PC -> 0x08000001 : INSN2
2922 We can't apply the same logic as for forward execution, because
2923 we would wrongly adjust the PC to 0x08000000, since there's a
2924 breakpoint at PC - 1. We'd then report a hit on B1, although
2925 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2927 if (execution_direction
== EXEC_REVERSE
)
2930 /* If this target does not decrement the PC after breakpoints, then
2931 we have nothing to do. */
2932 regcache
= get_thread_regcache (ecs
->ptid
);
2933 gdbarch
= get_regcache_arch (regcache
);
2934 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
2937 aspace
= get_regcache_aspace (regcache
);
2939 /* Find the location where (if we've hit a breakpoint) the
2940 breakpoint would be. */
2941 breakpoint_pc
= regcache_read_pc (regcache
)
2942 - gdbarch_decr_pc_after_break (gdbarch
);
2944 /* Check whether there actually is a software breakpoint inserted at
2947 If in non-stop mode, a race condition is possible where we've
2948 removed a breakpoint, but stop events for that breakpoint were
2949 already queued and arrive later. To suppress those spurious
2950 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
2951 and retire them after a number of stop events are reported. */
2952 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
2953 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
2955 struct cleanup
*old_cleanups
= NULL
;
2958 old_cleanups
= record_gdb_operation_disable_set ();
2960 /* When using hardware single-step, a SIGTRAP is reported for both
2961 a completed single-step and a software breakpoint. Need to
2962 differentiate between the two, as the latter needs adjusting
2963 but the former does not.
2965 The SIGTRAP can be due to a completed hardware single-step only if
2966 - we didn't insert software single-step breakpoints
2967 - the thread to be examined is still the current thread
2968 - this thread is currently being stepped
2970 If any of these events did not occur, we must have stopped due
2971 to hitting a software breakpoint, and have to back up to the
2974 As a special case, we could have hardware single-stepped a
2975 software breakpoint. In this case (prev_pc == breakpoint_pc),
2976 we also need to back up to the breakpoint address. */
2978 if (singlestep_breakpoints_inserted_p
2979 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
2980 || !currently_stepping (ecs
->event_thread
)
2981 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
2982 regcache_write_pc (regcache
, breakpoint_pc
);
2985 do_cleanups (old_cleanups
);
2990 init_infwait_state (void)
2992 waiton_ptid
= pid_to_ptid (-1);
2993 infwait_state
= infwait_normal_state
;
2997 error_is_running (void)
2999 error (_("Cannot execute this command while "
3000 "the selected thread is running."));
3004 ensure_not_running (void)
3006 if (is_running (inferior_ptid
))
3007 error_is_running ();
3011 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3013 for (frame
= get_prev_frame (frame
);
3015 frame
= get_prev_frame (frame
))
3017 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3019 if (get_frame_type (frame
) != INLINE_FRAME
)
3026 /* Auxiliary function that handles syscall entry/return events.
3027 It returns 1 if the inferior should keep going (and GDB
3028 should ignore the event), or 0 if the event deserves to be
3032 handle_syscall_event (struct execution_control_state
*ecs
)
3034 struct regcache
*regcache
;
3035 struct gdbarch
*gdbarch
;
3038 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3039 context_switch (ecs
->ptid
);
3041 regcache
= get_thread_regcache (ecs
->ptid
);
3042 gdbarch
= get_regcache_arch (regcache
);
3043 syscall_number
= gdbarch_get_syscall_number (gdbarch
, ecs
->ptid
);
3044 stop_pc
= regcache_read_pc (regcache
);
3046 target_last_waitstatus
.value
.syscall_number
= syscall_number
;
3048 if (catch_syscall_enabled () > 0
3049 && catching_syscall_number (syscall_number
) > 0)
3052 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3055 ecs
->event_thread
->control
.stop_bpstat
3056 = bpstat_stop_status (get_regcache_aspace (regcache
),
3057 stop_pc
, ecs
->ptid
);
3059 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3061 if (!ecs
->random_signal
)
3063 /* Catchpoint hit. */
3064 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_TRAP
;
3069 /* If no catchpoint triggered for this, then keep going. */
3070 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
3075 /* Clear the supplied execution_control_state's stop_func_* fields. */
3078 clear_stop_func (struct execution_control_state
*ecs
)
3080 ecs
->stop_func_filled_in
= 0;
3081 ecs
->stop_func_start
= 0;
3082 ecs
->stop_func_end
= 0;
3083 ecs
->stop_func_name
= NULL
;
3086 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3089 fill_in_stop_func (struct gdbarch
*gdbarch
,
3090 struct execution_control_state
*ecs
)
3092 if (!ecs
->stop_func_filled_in
)
3094 /* Don't care about return value; stop_func_start and stop_func_name
3095 will both be 0 if it doesn't work. */
3096 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3097 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3098 ecs
->stop_func_start
3099 += gdbarch_deprecated_function_start_offset (gdbarch
);
3101 ecs
->stop_func_filled_in
= 1;
3105 /* Given an execution control state that has been freshly filled in
3106 by an event from the inferior, figure out what it means and take
3107 appropriate action. */
3110 handle_inferior_event (struct execution_control_state
*ecs
)
3112 struct frame_info
*frame
;
3113 struct gdbarch
*gdbarch
;
3114 int stopped_by_watchpoint
;
3115 int stepped_after_stopped_by_watchpoint
= 0;
3116 struct symtab_and_line stop_pc_sal
;
3117 enum stop_kind stop_soon
;
3119 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3121 /* We had an event in the inferior, but we are not interested in
3122 handling it at this level. The lower layers have already
3123 done what needs to be done, if anything.
3125 One of the possible circumstances for this is when the
3126 inferior produces output for the console. The inferior has
3127 not stopped, and we are ignoring the event. Another possible
3128 circumstance is any event which the lower level knows will be
3129 reported multiple times without an intervening resume. */
3131 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3132 prepare_to_wait (ecs
);
3136 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3137 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
3139 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3142 stop_soon
= inf
->control
.stop_soon
;
3145 stop_soon
= NO_STOP_QUIETLY
;
3147 /* Cache the last pid/waitstatus. */
3148 target_last_wait_ptid
= ecs
->ptid
;
3149 target_last_waitstatus
= ecs
->ws
;
3151 /* Always clear state belonging to the previous time we stopped. */
3152 stop_stack_dummy
= STOP_NONE
;
3154 /* If it's a new process, add it to the thread database. */
3156 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
3157 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
3158 && !in_thread_list (ecs
->ptid
));
3160 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3161 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
3162 add_thread (ecs
->ptid
);
3164 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3166 /* Dependent on valid ECS->EVENT_THREAD. */
3167 adjust_pc_after_break (ecs
);
3169 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3170 reinit_frame_cache ();
3172 breakpoint_retire_moribund ();
3174 /* First, distinguish signals caused by the debugger from signals
3175 that have to do with the program's own actions. Note that
3176 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3177 on the operating system version. Here we detect when a SIGILL or
3178 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3179 something similar for SIGSEGV, since a SIGSEGV will be generated
3180 when we're trying to execute a breakpoint instruction on a
3181 non-executable stack. This happens for call dummy breakpoints
3182 for architectures like SPARC that place call dummies on the
3184 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3185 && (ecs
->ws
.value
.sig
== TARGET_SIGNAL_ILL
3186 || ecs
->ws
.value
.sig
== TARGET_SIGNAL_SEGV
3187 || ecs
->ws
.value
.sig
== TARGET_SIGNAL_EMT
))
3189 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3191 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3192 regcache_read_pc (regcache
)))
3195 fprintf_unfiltered (gdb_stdlog
,
3196 "infrun: Treating signal as SIGTRAP\n");
3197 ecs
->ws
.value
.sig
= TARGET_SIGNAL_TRAP
;
3201 /* Mark the non-executing threads accordingly. In all-stop, all
3202 threads of all processes are stopped when we get any event
3203 reported. In non-stop mode, only the event thread stops. If
3204 we're handling a process exit in non-stop mode, there's nothing
3205 to do, as threads of the dead process are gone, and threads of
3206 any other process were left running. */
3208 set_executing (minus_one_ptid
, 0);
3209 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3210 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3211 set_executing (inferior_ptid
, 0);
3213 switch (infwait_state
)
3215 case infwait_thread_hop_state
:
3217 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
3220 case infwait_normal_state
:
3222 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
3225 case infwait_step_watch_state
:
3227 fprintf_unfiltered (gdb_stdlog
,
3228 "infrun: infwait_step_watch_state\n");
3230 stepped_after_stopped_by_watchpoint
= 1;
3233 case infwait_nonstep_watch_state
:
3235 fprintf_unfiltered (gdb_stdlog
,
3236 "infrun: infwait_nonstep_watch_state\n");
3237 insert_breakpoints ();
3239 /* FIXME-maybe: is this cleaner than setting a flag? Does it
3240 handle things like signals arriving and other things happening
3241 in combination correctly? */
3242 stepped_after_stopped_by_watchpoint
= 1;
3246 internal_error (__FILE__
, __LINE__
, _("bad switch"));
3249 infwait_state
= infwait_normal_state
;
3250 waiton_ptid
= pid_to_ptid (-1);
3252 switch (ecs
->ws
.kind
)
3254 case TARGET_WAITKIND_LOADED
:
3256 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3257 /* Ignore gracefully during startup of the inferior, as it might
3258 be the shell which has just loaded some objects, otherwise
3259 add the symbols for the newly loaded objects. Also ignore at
3260 the beginning of an attach or remote session; we will query
3261 the full list of libraries once the connection is
3263 if (stop_soon
== NO_STOP_QUIETLY
)
3265 /* Check for any newly added shared libraries if we're
3266 supposed to be adding them automatically. Switch
3267 terminal for any messages produced by
3268 breakpoint_re_set. */
3269 target_terminal_ours_for_output ();
3270 /* NOTE: cagney/2003-11-25: Make certain that the target
3271 stack's section table is kept up-to-date. Architectures,
3272 (e.g., PPC64), use the section table to perform
3273 operations such as address => section name and hence
3274 require the table to contain all sections (including
3275 those found in shared libraries). */
3277 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
3279 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
3281 target_terminal_inferior ();
3283 /* If requested, stop when the dynamic linker notifies
3284 gdb of events. This allows the user to get control
3285 and place breakpoints in initializer routines for
3286 dynamically loaded objects (among other things). */
3287 if (stop_on_solib_events
)
3289 /* Make sure we print "Stopped due to solib-event" in
3291 stop_print_frame
= 1;
3293 stop_stepping (ecs
);
3297 /* NOTE drow/2007-05-11: This might be a good place to check
3298 for "catch load". */
3301 /* If we are skipping through a shell, or through shared library
3302 loading that we aren't interested in, resume the program. If
3303 we're running the program normally, also resume. But stop if
3304 we're attaching or setting up a remote connection. */
3305 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3307 /* Loading of shared libraries might have changed breakpoint
3308 addresses. Make sure new breakpoints are inserted. */
3309 if (stop_soon
== NO_STOP_QUIETLY
3310 && !breakpoints_always_inserted_mode ())
3311 insert_breakpoints ();
3312 resume (0, TARGET_SIGNAL_0
);
3313 prepare_to_wait (ecs
);
3319 case TARGET_WAITKIND_SPURIOUS
:
3321 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3322 resume (0, TARGET_SIGNAL_0
);
3323 prepare_to_wait (ecs
);
3326 case TARGET_WAITKIND_EXITED
:
3328 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
3329 inferior_ptid
= ecs
->ptid
;
3330 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3331 set_current_program_space (current_inferior ()->pspace
);
3332 handle_vfork_child_exec_or_exit (0);
3333 target_terminal_ours (); /* Must do this before mourn anyway. */
3334 print_exited_reason (ecs
->ws
.value
.integer
);
3336 /* Record the exit code in the convenience variable $_exitcode, so
3337 that the user can inspect this again later. */
3338 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3339 (LONGEST
) ecs
->ws
.value
.integer
);
3341 /* Also record this in the inferior itself. */
3342 current_inferior ()->has_exit_code
= 1;
3343 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3345 gdb_flush (gdb_stdout
);
3346 target_mourn_inferior ();
3347 singlestep_breakpoints_inserted_p
= 0;
3348 cancel_single_step_breakpoints ();
3349 stop_print_frame
= 0;
3350 stop_stepping (ecs
);
3353 case TARGET_WAITKIND_SIGNALLED
:
3355 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
3356 inferior_ptid
= ecs
->ptid
;
3357 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3358 set_current_program_space (current_inferior ()->pspace
);
3359 handle_vfork_child_exec_or_exit (0);
3360 stop_print_frame
= 0;
3361 target_terminal_ours (); /* Must do this before mourn anyway. */
3363 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
3364 reach here unless the inferior is dead. However, for years
3365 target_kill() was called here, which hints that fatal signals aren't
3366 really fatal on some systems. If that's true, then some changes
3368 target_mourn_inferior ();
3370 print_signal_exited_reason (ecs
->ws
.value
.sig
);
3371 singlestep_breakpoints_inserted_p
= 0;
3372 cancel_single_step_breakpoints ();
3373 stop_stepping (ecs
);
3376 /* The following are the only cases in which we keep going;
3377 the above cases end in a continue or goto. */
3378 case TARGET_WAITKIND_FORKED
:
3379 case TARGET_WAITKIND_VFORKED
:
3381 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3383 /* Check whether the inferior is displaced stepping. */
3385 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3386 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3387 struct displaced_step_inferior_state
*displaced
3388 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3390 /* If checking displaced stepping is supported, and thread
3391 ecs->ptid is displaced stepping. */
3392 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3394 struct inferior
*parent_inf
3395 = find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3396 struct regcache
*child_regcache
;
3397 CORE_ADDR parent_pc
;
3399 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3400 indicating that the displaced stepping of syscall instruction
3401 has been done. Perform cleanup for parent process here. Note
3402 that this operation also cleans up the child process for vfork,
3403 because their pages are shared. */
3404 displaced_step_fixup (ecs
->ptid
, TARGET_SIGNAL_TRAP
);
3406 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3408 /* Restore scratch pad for child process. */
3409 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3412 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3413 the child's PC is also within the scratchpad. Set the child's PC
3414 to the parent's PC value, which has already been fixed up.
3415 FIXME: we use the parent's aspace here, although we're touching
3416 the child, because the child hasn't been added to the inferior
3417 list yet at this point. */
3420 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3422 parent_inf
->aspace
);
3423 /* Read PC value of parent process. */
3424 parent_pc
= regcache_read_pc (regcache
);
3426 if (debug_displaced
)
3427 fprintf_unfiltered (gdb_stdlog
,
3428 "displaced: write child pc from %s to %s\n",
3430 regcache_read_pc (child_regcache
)),
3431 paddress (gdbarch
, parent_pc
));
3433 regcache_write_pc (child_regcache
, parent_pc
);
3437 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3439 context_switch (ecs
->ptid
);
3440 reinit_frame_cache ();
3443 /* Immediately detach breakpoints from the child before there's
3444 any chance of letting the user delete breakpoints from the
3445 breakpoint lists. If we don't do this early, it's easy to
3446 leave left over traps in the child, vis: "break foo; catch
3447 fork; c; <fork>; del; c; <child calls foo>". We only follow
3448 the fork on the last `continue', and by that time the
3449 breakpoint at "foo" is long gone from the breakpoint table.
3450 If we vforked, then we don't need to unpatch here, since both
3451 parent and child are sharing the same memory pages; we'll
3452 need to unpatch at follow/detach time instead to be certain
3453 that new breakpoints added between catchpoint hit time and
3454 vfork follow are detached. */
3455 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3457 int child_pid
= ptid_get_pid (ecs
->ws
.value
.related_pid
);
3459 /* This won't actually modify the breakpoint list, but will
3460 physically remove the breakpoints from the child. */
3461 detach_breakpoints (child_pid
);
3464 if (singlestep_breakpoints_inserted_p
)
3466 /* Pull the single step breakpoints out of the target. */
3467 remove_single_step_breakpoints ();
3468 singlestep_breakpoints_inserted_p
= 0;
3471 /* In case the event is caught by a catchpoint, remember that
3472 the event is to be followed at the next resume of the thread,
3473 and not immediately. */
3474 ecs
->event_thread
->pending_follow
= ecs
->ws
;
3476 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3478 ecs
->event_thread
->control
.stop_bpstat
3479 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3480 stop_pc
, ecs
->ptid
);
3482 /* Note that we're interested in knowing the bpstat actually
3483 causes a stop, not just if it may explain the signal.
3484 Software watchpoints, for example, always appear in the
3487 = !bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
);
3489 /* If no catchpoint triggered for this, then keep going. */
3490 if (ecs
->random_signal
)
3496 = (follow_fork_mode_string
== follow_fork_mode_child
);
3498 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
3500 should_resume
= follow_fork ();
3503 child
= ecs
->ws
.value
.related_pid
;
3505 /* In non-stop mode, also resume the other branch. */
3506 if (non_stop
&& !detach_fork
)
3509 switch_to_thread (parent
);
3511 switch_to_thread (child
);
3513 ecs
->event_thread
= inferior_thread ();
3514 ecs
->ptid
= inferior_ptid
;
3519 switch_to_thread (child
);
3521 switch_to_thread (parent
);
3523 ecs
->event_thread
= inferior_thread ();
3524 ecs
->ptid
= inferior_ptid
;
3529 stop_stepping (ecs
);
3532 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_TRAP
;
3533 goto process_event_stop_test
;
3535 case TARGET_WAITKIND_VFORK_DONE
:
3536 /* Done with the shared memory region. Re-insert breakpoints in
3537 the parent, and keep going. */
3540 fprintf_unfiltered (gdb_stdlog
,
3541 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3543 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3544 context_switch (ecs
->ptid
);
3546 current_inferior ()->waiting_for_vfork_done
= 0;
3547 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
3548 /* This also takes care of reinserting breakpoints in the
3549 previously locked inferior. */
3553 case TARGET_WAITKIND_EXECD
:
3555 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
3557 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3559 context_switch (ecs
->ptid
);
3560 reinit_frame_cache ();
3563 singlestep_breakpoints_inserted_p
= 0;
3564 cancel_single_step_breakpoints ();
3566 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3568 /* Do whatever is necessary to the parent branch of the vfork. */
3569 handle_vfork_child_exec_or_exit (1);
3571 /* This causes the eventpoints and symbol table to be reset.
3572 Must do this now, before trying to determine whether to
3574 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
3576 ecs
->event_thread
->control
.stop_bpstat
3577 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3578 stop_pc
, ecs
->ptid
);
3580 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3582 /* Note that this may be referenced from inside
3583 bpstat_stop_status above, through inferior_has_execd. */
3584 xfree (ecs
->ws
.value
.execd_pathname
);
3585 ecs
->ws
.value
.execd_pathname
= NULL
;
3587 /* If no catchpoint triggered for this, then keep going. */
3588 if (ecs
->random_signal
)
3590 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
3594 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_TRAP
;
3595 goto process_event_stop_test
;
3597 /* Be careful not to try to gather much state about a thread
3598 that's in a syscall. It's frequently a losing proposition. */
3599 case TARGET_WAITKIND_SYSCALL_ENTRY
:
3601 fprintf_unfiltered (gdb_stdlog
,
3602 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3603 /* Getting the current syscall number. */
3604 if (handle_syscall_event (ecs
) != 0)
3606 goto process_event_stop_test
;
3608 /* Before examining the threads further, step this thread to
3609 get it entirely out of the syscall. (We get notice of the
3610 event when the thread is just on the verge of exiting a
3611 syscall. Stepping one instruction seems to get it back
3613 case TARGET_WAITKIND_SYSCALL_RETURN
:
3615 fprintf_unfiltered (gdb_stdlog
,
3616 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3617 if (handle_syscall_event (ecs
) != 0)
3619 goto process_event_stop_test
;
3621 case TARGET_WAITKIND_STOPPED
:
3623 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
3624 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
3627 case TARGET_WAITKIND_NO_HISTORY
:
3628 /* Reverse execution: target ran out of history info. */
3629 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3630 print_no_history_reason ();
3631 stop_stepping (ecs
);
3635 if (ecs
->new_thread_event
)
3638 /* Non-stop assumes that the target handles adding new threads
3639 to the thread list. */
3640 internal_error (__FILE__
, __LINE__
,
3641 "targets should add new threads to the thread "
3642 "list themselves in non-stop mode.");
3644 /* We may want to consider not doing a resume here in order to
3645 give the user a chance to play with the new thread. It might
3646 be good to make that a user-settable option. */
3648 /* At this point, all threads are stopped (happens automatically
3649 in either the OS or the native code). Therefore we need to
3650 continue all threads in order to make progress. */
3652 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3653 context_switch (ecs
->ptid
);
3654 target_resume (RESUME_ALL
, 0, TARGET_SIGNAL_0
);
3655 prepare_to_wait (ecs
);
3659 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
3661 /* Do we need to clean up the state of a thread that has
3662 completed a displaced single-step? (Doing so usually affects
3663 the PC, so do it here, before we set stop_pc.) */
3664 displaced_step_fixup (ecs
->ptid
,
3665 ecs
->event_thread
->suspend
.stop_signal
);
3667 /* If we either finished a single-step or hit a breakpoint, but
3668 the user wanted this thread to be stopped, pretend we got a
3669 SIG0 (generic unsignaled stop). */
3671 if (ecs
->event_thread
->stop_requested
3672 && ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
)
3673 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
3676 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3680 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3681 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3682 struct cleanup
*old_chain
= save_inferior_ptid ();
3684 inferior_ptid
= ecs
->ptid
;
3686 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
3687 paddress (gdbarch
, stop_pc
));
3688 if (target_stopped_by_watchpoint ())
3692 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
3694 if (target_stopped_data_address (¤t_target
, &addr
))
3695 fprintf_unfiltered (gdb_stdlog
,
3696 "infrun: stopped data address = %s\n",
3697 paddress (gdbarch
, addr
));
3699 fprintf_unfiltered (gdb_stdlog
,
3700 "infrun: (no data address available)\n");
3703 do_cleanups (old_chain
);
3706 if (stepping_past_singlestep_breakpoint
)
3708 gdb_assert (singlestep_breakpoints_inserted_p
);
3709 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
3710 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
3712 stepping_past_singlestep_breakpoint
= 0;
3714 /* We've either finished single-stepping past the single-step
3715 breakpoint, or stopped for some other reason. It would be nice if
3716 we could tell, but we can't reliably. */
3717 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
)
3720 fprintf_unfiltered (gdb_stdlog
,
3721 "infrun: stepping_past_"
3722 "singlestep_breakpoint\n");
3723 /* Pull the single step breakpoints out of the target. */
3724 remove_single_step_breakpoints ();
3725 singlestep_breakpoints_inserted_p
= 0;
3727 ecs
->random_signal
= 0;
3728 ecs
->event_thread
->control
.trap_expected
= 0;
3730 context_switch (saved_singlestep_ptid
);
3731 if (deprecated_context_hook
)
3732 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3734 resume (1, TARGET_SIGNAL_0
);
3735 prepare_to_wait (ecs
);
3740 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
3742 /* In non-stop mode, there's never a deferred_step_ptid set. */
3743 gdb_assert (!non_stop
);
3745 /* If we stopped for some other reason than single-stepping, ignore
3746 the fact that we were supposed to switch back. */
3747 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
)
3750 fprintf_unfiltered (gdb_stdlog
,
3751 "infrun: handling deferred step\n");
3753 /* Pull the single step breakpoints out of the target. */
3754 if (singlestep_breakpoints_inserted_p
)
3756 remove_single_step_breakpoints ();
3757 singlestep_breakpoints_inserted_p
= 0;
3760 ecs
->event_thread
->control
.trap_expected
= 0;
3762 /* Note: We do not call context_switch at this point, as the
3763 context is already set up for stepping the original thread. */
3764 switch_to_thread (deferred_step_ptid
);
3765 deferred_step_ptid
= null_ptid
;
3766 /* Suppress spurious "Switching to ..." message. */
3767 previous_inferior_ptid
= inferior_ptid
;
3769 resume (1, TARGET_SIGNAL_0
);
3770 prepare_to_wait (ecs
);
3774 deferred_step_ptid
= null_ptid
;
3777 /* See if a thread hit a thread-specific breakpoint that was meant for
3778 another thread. If so, then step that thread past the breakpoint,
3781 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
)
3783 int thread_hop_needed
= 0;
3784 struct address_space
*aspace
=
3785 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
3787 /* Check if a regular breakpoint has been hit before checking
3788 for a potential single step breakpoint. Otherwise, GDB will
3789 not see this breakpoint hit when stepping onto breakpoints. */
3790 if (regular_breakpoint_inserted_here_p (aspace
, stop_pc
))
3792 ecs
->random_signal
= 0;
3793 if (!breakpoint_thread_match (aspace
, stop_pc
, ecs
->ptid
))
3794 thread_hop_needed
= 1;
3796 else if (singlestep_breakpoints_inserted_p
)
3798 /* We have not context switched yet, so this should be true
3799 no matter which thread hit the singlestep breakpoint. */
3800 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
3802 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
3804 target_pid_to_str (ecs
->ptid
));
3806 ecs
->random_signal
= 0;
3807 /* The call to in_thread_list is necessary because PTIDs sometimes
3808 change when we go from single-threaded to multi-threaded. If
3809 the singlestep_ptid is still in the list, assume that it is
3810 really different from ecs->ptid. */
3811 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
3812 && in_thread_list (singlestep_ptid
))
3814 /* If the PC of the thread we were trying to single-step
3815 has changed, discard this event (which we were going
3816 to ignore anyway), and pretend we saw that thread
3817 trap. This prevents us continuously moving the
3818 single-step breakpoint forward, one instruction at a
3819 time. If the PC has changed, then the thread we were
3820 trying to single-step has trapped or been signalled,
3821 but the event has not been reported to GDB yet.
3823 There might be some cases where this loses signal
3824 information, if a signal has arrived at exactly the
3825 same time that the PC changed, but this is the best
3826 we can do with the information available. Perhaps we
3827 should arrange to report all events for all threads
3828 when they stop, or to re-poll the remote looking for
3829 this particular thread (i.e. temporarily enable
3832 CORE_ADDR new_singlestep_pc
3833 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
3835 if (new_singlestep_pc
!= singlestep_pc
)
3837 enum target_signal stop_signal
;
3840 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
3841 " but expected thread advanced also\n");
3843 /* The current context still belongs to
3844 singlestep_ptid. Don't swap here, since that's
3845 the context we want to use. Just fudge our
3846 state and continue. */
3847 stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
3848 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
3849 ecs
->ptid
= singlestep_ptid
;
3850 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3851 ecs
->event_thread
->suspend
.stop_signal
= stop_signal
;
3852 stop_pc
= new_singlestep_pc
;
3857 fprintf_unfiltered (gdb_stdlog
,
3858 "infrun: unexpected thread\n");
3860 thread_hop_needed
= 1;
3861 stepping_past_singlestep_breakpoint
= 1;
3862 saved_singlestep_ptid
= singlestep_ptid
;
3867 if (thread_hop_needed
)
3869 struct regcache
*thread_regcache
;
3870 int remove_status
= 0;
3873 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
3875 /* Switch context before touching inferior memory, the
3876 previous thread may have exited. */
3877 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
3878 context_switch (ecs
->ptid
);
3880 /* Saw a breakpoint, but it was hit by the wrong thread.
3883 if (singlestep_breakpoints_inserted_p
)
3885 /* Pull the single step breakpoints out of the target. */
3886 remove_single_step_breakpoints ();
3887 singlestep_breakpoints_inserted_p
= 0;
3890 /* If the arch can displace step, don't remove the
3892 thread_regcache
= get_thread_regcache (ecs
->ptid
);
3893 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
3894 remove_status
= remove_breakpoints ();
3896 /* Did we fail to remove breakpoints? If so, try
3897 to set the PC past the bp. (There's at least
3898 one situation in which we can fail to remove
3899 the bp's: On HP-UX's that use ttrace, we can't
3900 change the address space of a vforking child
3901 process until the child exits (well, okay, not
3902 then either :-) or execs. */
3903 if (remove_status
!= 0)
3904 error (_("Cannot step over breakpoint hit in wrong thread"));
3909 /* Only need to require the next event from this
3910 thread in all-stop mode. */
3911 waiton_ptid
= ecs
->ptid
;
3912 infwait_state
= infwait_thread_hop_state
;
3915 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3920 else if (singlestep_breakpoints_inserted_p
)
3922 ecs
->random_signal
= 0;
3926 ecs
->random_signal
= 1;
3928 /* See if something interesting happened to the non-current thread. If
3929 so, then switch to that thread. */
3930 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3933 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
3935 context_switch (ecs
->ptid
);
3937 if (deprecated_context_hook
)
3938 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3941 /* At this point, get hold of the now-current thread's frame. */
3942 frame
= get_current_frame ();
3943 gdbarch
= get_frame_arch (frame
);
3945 if (singlestep_breakpoints_inserted_p
)
3947 /* Pull the single step breakpoints out of the target. */
3948 remove_single_step_breakpoints ();
3949 singlestep_breakpoints_inserted_p
= 0;
3952 if (stepped_after_stopped_by_watchpoint
)
3953 stopped_by_watchpoint
= 0;
3955 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
3957 /* If necessary, step over this watchpoint. We'll be back to display
3959 if (stopped_by_watchpoint
3960 && (target_have_steppable_watchpoint
3961 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
3963 /* At this point, we are stopped at an instruction which has
3964 attempted to write to a piece of memory under control of
3965 a watchpoint. The instruction hasn't actually executed
3966 yet. If we were to evaluate the watchpoint expression
3967 now, we would get the old value, and therefore no change
3968 would seem to have occurred.
3970 In order to make watchpoints work `right', we really need
3971 to complete the memory write, and then evaluate the
3972 watchpoint expression. We do this by single-stepping the
3975 It may not be necessary to disable the watchpoint to stop over
3976 it. For example, the PA can (with some kernel cooperation)
3977 single step over a watchpoint without disabling the watchpoint.
3979 It is far more common to need to disable a watchpoint to step
3980 the inferior over it. If we have non-steppable watchpoints,
3981 we must disable the current watchpoint; it's simplest to
3982 disable all watchpoints and breakpoints. */
3985 if (!target_have_steppable_watchpoint
)
3987 remove_breakpoints ();
3988 /* See comment in resume why we need to stop bypassing signals
3989 while breakpoints have been removed. */
3990 target_pass_signals (0, NULL
);
3993 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
3994 target_resume (ecs
->ptid
, hw_step
, TARGET_SIGNAL_0
);
3995 waiton_ptid
= ecs
->ptid
;
3996 if (target_have_steppable_watchpoint
)
3997 infwait_state
= infwait_step_watch_state
;
3999 infwait_state
= infwait_nonstep_watch_state
;
4000 prepare_to_wait (ecs
);
4004 clear_stop_func (ecs
);
4005 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4006 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4007 ecs
->event_thread
->control
.stop_step
= 0;
4008 stop_print_frame
= 1;
4009 ecs
->random_signal
= 0;
4010 stopped_by_random_signal
= 0;
4012 /* Hide inlined functions starting here, unless we just performed stepi or
4013 nexti. After stepi and nexti, always show the innermost frame (not any
4014 inline function call sites). */
4015 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4016 skip_inline_frames (ecs
->ptid
);
4018 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
4019 && ecs
->event_thread
->control
.trap_expected
4020 && gdbarch_single_step_through_delay_p (gdbarch
)
4021 && currently_stepping (ecs
->event_thread
))
4023 /* We're trying to step off a breakpoint. Turns out that we're
4024 also on an instruction that needs to be stepped multiple
4025 times before it's been fully executing. E.g., architectures
4026 with a delay slot. It needs to be stepped twice, once for
4027 the instruction and once for the delay slot. */
4028 int step_through_delay
4029 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4031 if (debug_infrun
&& step_through_delay
)
4032 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4033 if (ecs
->event_thread
->control
.step_range_end
== 0
4034 && step_through_delay
)
4036 /* The user issued a continue when stopped at a breakpoint.
4037 Set up for another trap and get out of here. */
4038 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4042 else if (step_through_delay
)
4044 /* The user issued a step when stopped at a breakpoint.
4045 Maybe we should stop, maybe we should not - the delay
4046 slot *might* correspond to a line of source. In any
4047 case, don't decide that here, just set
4048 ecs->stepping_over_breakpoint, making sure we
4049 single-step again before breakpoints are re-inserted. */
4050 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4054 /* Look at the cause of the stop, and decide what to do.
4055 The alternatives are:
4056 1) stop_stepping and return; to really stop and return to the debugger,
4057 2) keep_going and return to start up again
4058 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
4059 3) set ecs->random_signal to 1, and the decision between 1 and 2
4060 will be made according to the signal handling tables. */
4062 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
4063 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4064 || stop_soon
== STOP_QUIETLY_REMOTE
)
4066 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
4070 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4071 stop_print_frame
= 0;
4072 stop_stepping (ecs
);
4076 /* This is originated from start_remote(), start_inferior() and
4077 shared libraries hook functions. */
4078 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4081 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4082 stop_stepping (ecs
);
4086 /* This originates from attach_command(). We need to overwrite
4087 the stop_signal here, because some kernels don't ignore a
4088 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4089 See more comments in inferior.h. On the other hand, if we
4090 get a non-SIGSTOP, report it to the user - assume the backend
4091 will handle the SIGSTOP if it should show up later.
4093 Also consider that the attach is complete when we see a
4094 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4095 target extended-remote report it instead of a SIGSTOP
4096 (e.g. gdbserver). We already rely on SIGTRAP being our
4097 signal, so this is no exception.
4099 Also consider that the attach is complete when we see a
4100 TARGET_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4101 the target to stop all threads of the inferior, in case the
4102 low level attach operation doesn't stop them implicitly. If
4103 they weren't stopped implicitly, then the stub will report a
4104 TARGET_SIGNAL_0, meaning: stopped for no particular reason
4105 other than GDB's request. */
4106 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4107 && (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_STOP
4108 || ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
4109 || ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_0
))
4111 stop_stepping (ecs
);
4112 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
4116 /* See if there is a breakpoint at the current PC. */
4117 ecs
->event_thread
->control
.stop_bpstat
4118 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4119 stop_pc
, ecs
->ptid
);
4121 /* Following in case break condition called a
4123 stop_print_frame
= 1;
4125 /* This is where we handle "moribund" watchpoints. Unlike
4126 software breakpoints traps, hardware watchpoint traps are
4127 always distinguishable from random traps. If no high-level
4128 watchpoint is associated with the reported stop data address
4129 anymore, then the bpstat does not explain the signal ---
4130 simply make sure to ignore it if `stopped_by_watchpoint' is
4134 && ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
4135 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4136 && stopped_by_watchpoint
)
4137 fprintf_unfiltered (gdb_stdlog
,
4138 "infrun: no user watchpoint explains "
4139 "watchpoint SIGTRAP, ignoring\n");
4141 /* NOTE: cagney/2003-03-29: These two checks for a random signal
4142 at one stage in the past included checks for an inferior
4143 function call's call dummy's return breakpoint. The original
4144 comment, that went with the test, read:
4146 ``End of a stack dummy. Some systems (e.g. Sony news) give
4147 another signal besides SIGTRAP, so check here as well as
4150 If someone ever tries to get call dummys on a
4151 non-executable stack to work (where the target would stop
4152 with something like a SIGSEGV), then those tests might need
4153 to be re-instated. Given, however, that the tests were only
4154 enabled when momentary breakpoints were not being used, I
4155 suspect that it won't be the case.
4157 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4158 be necessary for call dummies on a non-executable stack on
4161 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
)
4163 = !(bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4164 || stopped_by_watchpoint
4165 || ecs
->event_thread
->control
.trap_expected
4166 || (ecs
->event_thread
->control
.step_range_end
4167 && (ecs
->event_thread
->control
.step_resume_breakpoint
4171 ecs
->random_signal
= !bpstat_explains_signal
4172 (ecs
->event_thread
->control
.stop_bpstat
);
4173 if (!ecs
->random_signal
)
4174 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_TRAP
;
4178 /* When we reach this point, we've pretty much decided
4179 that the reason for stopping must've been a random
4180 (unexpected) signal. */
4183 ecs
->random_signal
= 1;
4185 process_event_stop_test
:
4187 /* Re-fetch current thread's frame in case we did a
4188 "goto process_event_stop_test" above. */
4189 frame
= get_current_frame ();
4190 gdbarch
= get_frame_arch (frame
);
4192 /* For the program's own signals, act according to
4193 the signal handling tables. */
4195 if (ecs
->random_signal
)
4197 /* Signal not for debugging purposes. */
4199 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
4202 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
4203 ecs
->event_thread
->suspend
.stop_signal
);
4205 stopped_by_random_signal
= 1;
4207 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4210 target_terminal_ours_for_output ();
4211 print_signal_received_reason
4212 (ecs
->event_thread
->suspend
.stop_signal
);
4214 /* Always stop on signals if we're either just gaining control
4215 of the program, or the user explicitly requested this thread
4216 to remain stopped. */
4217 if (stop_soon
!= NO_STOP_QUIETLY
4218 || ecs
->event_thread
->stop_requested
4220 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4222 stop_stepping (ecs
);
4225 /* If not going to stop, give terminal back
4226 if we took it away. */
4228 target_terminal_inferior ();
4230 /* Clear the signal if it should not be passed. */
4231 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4232 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
4234 if (ecs
->event_thread
->prev_pc
== stop_pc
4235 && ecs
->event_thread
->control
.trap_expected
4236 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4238 /* We were just starting a new sequence, attempting to
4239 single-step off of a breakpoint and expecting a SIGTRAP.
4240 Instead this signal arrives. This signal will take us out
4241 of the stepping range so GDB needs to remember to, when
4242 the signal handler returns, resume stepping off that
4244 /* To simplify things, "continue" is forced to use the same
4245 code paths as single-step - set a breakpoint at the
4246 signal return address and then, once hit, step off that
4249 fprintf_unfiltered (gdb_stdlog
,
4250 "infrun: signal arrived while stepping over "
4253 insert_hp_step_resume_breakpoint_at_frame (frame
);
4254 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4255 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4256 ecs
->event_thread
->control
.trap_expected
= 0;
4261 if (ecs
->event_thread
->control
.step_range_end
!= 0
4262 && ecs
->event_thread
->suspend
.stop_signal
!= TARGET_SIGNAL_0
4263 && (ecs
->event_thread
->control
.step_range_start
<= stop_pc
4264 && stop_pc
< ecs
->event_thread
->control
.step_range_end
)
4265 && frame_id_eq (get_stack_frame_id (frame
),
4266 ecs
->event_thread
->control
.step_stack_frame_id
)
4267 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4269 /* The inferior is about to take a signal that will take it
4270 out of the single step range. Set a breakpoint at the
4271 current PC (which is presumably where the signal handler
4272 will eventually return) and then allow the inferior to
4275 Note that this is only needed for a signal delivered
4276 while in the single-step range. Nested signals aren't a
4277 problem as they eventually all return. */
4279 fprintf_unfiltered (gdb_stdlog
,
4280 "infrun: signal may take us out of "
4281 "single-step range\n");
4283 insert_hp_step_resume_breakpoint_at_frame (frame
);
4284 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4285 ecs
->event_thread
->control
.trap_expected
= 0;
4290 /* Note: step_resume_breakpoint may be non-NULL. This occures
4291 when either there's a nested signal, or when there's a
4292 pending signal enabled just as the signal handler returns
4293 (leaving the inferior at the step-resume-breakpoint without
4294 actually executing it). Either way continue until the
4295 breakpoint is really hit. */
4300 /* Handle cases caused by hitting a breakpoint. */
4302 CORE_ADDR jmp_buf_pc
;
4303 struct bpstat_what what
;
4305 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4307 if (what
.call_dummy
)
4309 stop_stack_dummy
= what
.call_dummy
;
4312 /* If we hit an internal event that triggers symbol changes, the
4313 current frame will be invalidated within bpstat_what (e.g., if
4314 we hit an internal solib event). Re-fetch it. */
4315 frame
= get_current_frame ();
4316 gdbarch
= get_frame_arch (frame
);
4318 switch (what
.main_action
)
4320 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4321 /* If we hit the breakpoint at longjmp while stepping, we
4322 install a momentary breakpoint at the target of the
4326 fprintf_unfiltered (gdb_stdlog
,
4327 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4329 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4331 if (what
.is_longjmp
)
4333 if (!gdbarch_get_longjmp_target_p (gdbarch
)
4334 || !gdbarch_get_longjmp_target (gdbarch
,
4335 frame
, &jmp_buf_pc
))
4338 fprintf_unfiltered (gdb_stdlog
,
4339 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4340 "(!gdbarch_get_longjmp_target)\n");
4345 /* We're going to replace the current step-resume breakpoint
4346 with a longjmp-resume breakpoint. */
4347 delete_step_resume_breakpoint (ecs
->event_thread
);
4349 /* Insert a breakpoint at resume address. */
4350 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4354 struct symbol
*func
= get_frame_function (frame
);
4357 check_exception_resume (ecs
, frame
, func
);
4362 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4364 fprintf_unfiltered (gdb_stdlog
,
4365 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4367 if (what
.is_longjmp
)
4369 gdb_assert (ecs
->event_thread
->control
.step_resume_breakpoint
4371 delete_step_resume_breakpoint (ecs
->event_thread
);
4375 /* There are several cases to consider.
4377 1. The initiating frame no longer exists. In this case
4378 we must stop, because the exception has gone too far.
4380 2. The initiating frame exists, and is the same as the
4381 current frame. We stop, because the exception has been
4384 3. The initiating frame exists and is different from
4385 the current frame. This means the exception has been
4386 caught beneath the initiating frame, so keep going. */
4387 struct frame_info
*init_frame
4388 = frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4390 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4392 delete_exception_resume_breakpoint (ecs
->event_thread
);
4396 struct frame_id current_id
4397 = get_frame_id (get_current_frame ());
4398 if (frame_id_eq (current_id
,
4399 ecs
->event_thread
->initiating_frame
))
4401 /* Case 2. Fall through. */
4411 /* For Cases 1 and 2, remove the step-resume breakpoint,
4413 delete_step_resume_breakpoint (ecs
->event_thread
);
4416 ecs
->event_thread
->control
.stop_step
= 1;
4417 print_end_stepping_range_reason ();
4418 stop_stepping (ecs
);
4421 case BPSTAT_WHAT_SINGLE
:
4423 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4424 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4425 /* Still need to check other stuff, at least the case
4426 where we are stepping and step out of the right range. */
4429 case BPSTAT_WHAT_STEP_RESUME
:
4431 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4433 delete_step_resume_breakpoint (ecs
->event_thread
);
4434 if (ecs
->event_thread
->control
.proceed_to_finish
4435 && execution_direction
== EXEC_REVERSE
)
4437 struct thread_info
*tp
= ecs
->event_thread
;
4439 /* We are finishing a function in reverse, and just hit
4440 the step-resume breakpoint at the start address of the
4441 function, and we're almost there -- just need to back
4442 up by one more single-step, which should take us back
4443 to the function call. */
4444 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4448 fill_in_stop_func (gdbarch
, ecs
);
4449 if (stop_pc
== ecs
->stop_func_start
4450 && execution_direction
== EXEC_REVERSE
)
4452 /* We are stepping over a function call in reverse, and
4453 just hit the step-resume breakpoint at the start
4454 address of the function. Go back to single-stepping,
4455 which should take us back to the function call. */
4456 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4462 case BPSTAT_WHAT_STOP_NOISY
:
4464 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4465 stop_print_frame
= 1;
4467 /* We are about to nuke the step_resume_breakpointt via the
4468 cleanup chain, so no need to worry about it here. */
4470 stop_stepping (ecs
);
4473 case BPSTAT_WHAT_STOP_SILENT
:
4475 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4476 stop_print_frame
= 0;
4478 /* We are about to nuke the step_resume_breakpoin via the
4479 cleanup chain, so no need to worry about it here. */
4481 stop_stepping (ecs
);
4484 case BPSTAT_WHAT_HP_STEP_RESUME
:
4486 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4488 delete_step_resume_breakpoint (ecs
->event_thread
);
4489 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4491 /* Back when the step-resume breakpoint was inserted, we
4492 were trying to single-step off a breakpoint. Go back
4494 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4495 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4501 case BPSTAT_WHAT_KEEP_CHECKING
:
4506 /* We come here if we hit a breakpoint but should not
4507 stop for it. Possibly we also were stepping
4508 and should stop for that. So fall through and
4509 test for stepping. But, if not stepping,
4512 /* In all-stop mode, if we're currently stepping but have stopped in
4513 some other thread, we need to switch back to the stepped thread. */
4516 struct thread_info
*tp
;
4518 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
4522 /* However, if the current thread is blocked on some internal
4523 breakpoint, and we simply need to step over that breakpoint
4524 to get it going again, do that first. */
4525 if ((ecs
->event_thread
->control
.trap_expected
4526 && ecs
->event_thread
->suspend
.stop_signal
!= TARGET_SIGNAL_TRAP
)
4527 || ecs
->event_thread
->stepping_over_breakpoint
)
4533 /* If the stepping thread exited, then don't try to switch
4534 back and resume it, which could fail in several different
4535 ways depending on the target. Instead, just keep going.
4537 We can find a stepping dead thread in the thread list in
4540 - The target supports thread exit events, and when the
4541 target tries to delete the thread from the thread list,
4542 inferior_ptid pointed at the exiting thread. In such
4543 case, calling delete_thread does not really remove the
4544 thread from the list; instead, the thread is left listed,
4545 with 'exited' state.
4547 - The target's debug interface does not support thread
4548 exit events, and so we have no idea whatsoever if the
4549 previously stepping thread is still alive. For that
4550 reason, we need to synchronously query the target
4552 if (is_exited (tp
->ptid
)
4553 || !target_thread_alive (tp
->ptid
))
4556 fprintf_unfiltered (gdb_stdlog
,
4557 "infrun: not switching back to "
4558 "stepped thread, it has vanished\n");
4560 delete_thread (tp
->ptid
);
4565 /* Otherwise, we no longer expect a trap in the current thread.
4566 Clear the trap_expected flag before switching back -- this is
4567 what keep_going would do as well, if we called it. */
4568 ecs
->event_thread
->control
.trap_expected
= 0;
4571 fprintf_unfiltered (gdb_stdlog
,
4572 "infrun: switching back to stepped thread\n");
4574 ecs
->event_thread
= tp
;
4575 ecs
->ptid
= tp
->ptid
;
4576 context_switch (ecs
->ptid
);
4582 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4585 fprintf_unfiltered (gdb_stdlog
,
4586 "infrun: step-resume breakpoint is inserted\n");
4588 /* Having a step-resume breakpoint overrides anything
4589 else having to do with stepping commands until
4590 that breakpoint is reached. */
4595 if (ecs
->event_thread
->control
.step_range_end
== 0)
4598 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4599 /* Likewise if we aren't even stepping. */
4604 /* Re-fetch current thread's frame in case the code above caused
4605 the frame cache to be re-initialized, making our FRAME variable
4606 a dangling pointer. */
4607 frame
= get_current_frame ();
4608 gdbarch
= get_frame_arch (frame
);
4609 fill_in_stop_func (gdbarch
, ecs
);
4611 /* If stepping through a line, keep going if still within it.
4613 Note that step_range_end is the address of the first instruction
4614 beyond the step range, and NOT the address of the last instruction
4617 Note also that during reverse execution, we may be stepping
4618 through a function epilogue and therefore must detect when
4619 the current-frame changes in the middle of a line. */
4621 if (stop_pc
>= ecs
->event_thread
->control
.step_range_start
4622 && stop_pc
< ecs
->event_thread
->control
.step_range_end
4623 && (execution_direction
!= EXEC_REVERSE
4624 || frame_id_eq (get_frame_id (frame
),
4625 ecs
->event_thread
->control
.step_frame_id
)))
4629 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4630 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4631 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4633 /* When stepping backward, stop at beginning of line range
4634 (unless it's the function entry point, in which case
4635 keep going back to the call point). */
4636 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4637 && stop_pc
!= ecs
->stop_func_start
4638 && execution_direction
== EXEC_REVERSE
)
4640 ecs
->event_thread
->control
.stop_step
= 1;
4641 print_end_stepping_range_reason ();
4642 stop_stepping (ecs
);
4650 /* We stepped out of the stepping range. */
4652 /* If we are stepping at the source level and entered the runtime
4653 loader dynamic symbol resolution code...
4655 EXEC_FORWARD: we keep on single stepping until we exit the run
4656 time loader code and reach the callee's address.
4658 EXEC_REVERSE: we've already executed the callee (backward), and
4659 the runtime loader code is handled just like any other
4660 undebuggable function call. Now we need only keep stepping
4661 backward through the trampoline code, and that's handled further
4662 down, so there is nothing for us to do here. */
4664 if (execution_direction
!= EXEC_REVERSE
4665 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4666 && in_solib_dynsym_resolve_code (stop_pc
))
4668 CORE_ADDR pc_after_resolver
=
4669 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
4672 fprintf_unfiltered (gdb_stdlog
,
4673 "infrun: stepped into dynsym resolve code\n");
4675 if (pc_after_resolver
)
4677 /* Set up a step-resume breakpoint at the address
4678 indicated by SKIP_SOLIB_RESOLVER. */
4679 struct symtab_and_line sr_sal
;
4682 sr_sal
.pc
= pc_after_resolver
;
4683 sr_sal
.pspace
= get_frame_program_space (frame
);
4685 insert_step_resume_breakpoint_at_sal (gdbarch
,
4686 sr_sal
, null_frame_id
);
4693 if (ecs
->event_thread
->control
.step_range_end
!= 1
4694 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4695 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4696 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
4699 fprintf_unfiltered (gdb_stdlog
,
4700 "infrun: stepped into signal trampoline\n");
4701 /* The inferior, while doing a "step" or "next", has ended up in
4702 a signal trampoline (either by a signal being delivered or by
4703 the signal handler returning). Just single-step until the
4704 inferior leaves the trampoline (either by calling the handler
4710 /* Check for subroutine calls. The check for the current frame
4711 equalling the step ID is not necessary - the check of the
4712 previous frame's ID is sufficient - but it is a common case and
4713 cheaper than checking the previous frame's ID.
4715 NOTE: frame_id_eq will never report two invalid frame IDs as
4716 being equal, so to get into this block, both the current and
4717 previous frame must have valid frame IDs. */
4718 /* The outer_frame_id check is a heuristic to detect stepping
4719 through startup code. If we step over an instruction which
4720 sets the stack pointer from an invalid value to a valid value,
4721 we may detect that as a subroutine call from the mythical
4722 "outermost" function. This could be fixed by marking
4723 outermost frames as !stack_p,code_p,special_p. Then the
4724 initial outermost frame, before sp was valid, would
4725 have code_addr == &_start. See the comment in frame_id_eq
4727 if (!frame_id_eq (get_stack_frame_id (frame
),
4728 ecs
->event_thread
->control
.step_stack_frame_id
)
4729 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4730 ecs
->event_thread
->control
.step_stack_frame_id
)
4731 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
4733 || step_start_function
!= find_pc_function (stop_pc
))))
4735 CORE_ADDR real_stop_pc
;
4738 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
4740 if ((ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
4741 || ((ecs
->event_thread
->control
.step_range_end
== 1)
4742 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
4743 ecs
->stop_func_start
)))
4745 /* I presume that step_over_calls is only 0 when we're
4746 supposed to be stepping at the assembly language level
4747 ("stepi"). Just stop. */
4748 /* Also, maybe we just did a "nexti" inside a prolog, so we
4749 thought it was a subroutine call but it was not. Stop as
4751 /* And this works the same backward as frontward. MVS */
4752 ecs
->event_thread
->control
.stop_step
= 1;
4753 print_end_stepping_range_reason ();
4754 stop_stepping (ecs
);
4758 /* Reverse stepping through solib trampolines. */
4760 if (execution_direction
== EXEC_REVERSE
4761 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
4762 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4763 || (ecs
->stop_func_start
== 0
4764 && in_solib_dynsym_resolve_code (stop_pc
))))
4766 /* Any solib trampoline code can be handled in reverse
4767 by simply continuing to single-step. We have already
4768 executed the solib function (backwards), and a few
4769 steps will take us back through the trampoline to the
4775 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4777 /* We're doing a "next".
4779 Normal (forward) execution: set a breakpoint at the
4780 callee's return address (the address at which the caller
4783 Reverse (backward) execution. set the step-resume
4784 breakpoint at the start of the function that we just
4785 stepped into (backwards), and continue to there. When we
4786 get there, we'll need to single-step back to the caller. */
4788 if (execution_direction
== EXEC_REVERSE
)
4790 struct symtab_and_line sr_sal
;
4792 /* Normal function call return (static or dynamic). */
4794 sr_sal
.pc
= ecs
->stop_func_start
;
4795 sr_sal
.pspace
= get_frame_program_space (frame
);
4796 insert_step_resume_breakpoint_at_sal (gdbarch
,
4797 sr_sal
, null_frame_id
);
4800 insert_step_resume_breakpoint_at_caller (frame
);
4806 /* If we are in a function call trampoline (a stub between the
4807 calling routine and the real function), locate the real
4808 function. That's what tells us (a) whether we want to step
4809 into it at all, and (b) what prologue we want to run to the
4810 end of, if we do step into it. */
4811 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
4812 if (real_stop_pc
== 0)
4813 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4814 if (real_stop_pc
!= 0)
4815 ecs
->stop_func_start
= real_stop_pc
;
4817 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
4819 struct symtab_and_line sr_sal
;
4822 sr_sal
.pc
= ecs
->stop_func_start
;
4823 sr_sal
.pspace
= get_frame_program_space (frame
);
4825 insert_step_resume_breakpoint_at_sal (gdbarch
,
4826 sr_sal
, null_frame_id
);
4831 /* If we have line number information for the function we are
4832 thinking of stepping into, step into it.
4834 If there are several symtabs at that PC (e.g. with include
4835 files), just want to know whether *any* of them have line
4836 numbers. find_pc_line handles this. */
4838 struct symtab_and_line tmp_sal
;
4840 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4841 if (tmp_sal
.line
!= 0)
4843 if (execution_direction
== EXEC_REVERSE
)
4844 handle_step_into_function_backward (gdbarch
, ecs
);
4846 handle_step_into_function (gdbarch
, ecs
);
4851 /* If we have no line number and the step-stop-if-no-debug is
4852 set, we stop the step so that the user has a chance to switch
4853 in assembly mode. */
4854 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4855 && step_stop_if_no_debug
)
4857 ecs
->event_thread
->control
.stop_step
= 1;
4858 print_end_stepping_range_reason ();
4859 stop_stepping (ecs
);
4863 if (execution_direction
== EXEC_REVERSE
)
4865 /* Set a breakpoint at callee's start address.
4866 From there we can step once and be back in the caller. */
4867 struct symtab_and_line sr_sal
;
4870 sr_sal
.pc
= ecs
->stop_func_start
;
4871 sr_sal
.pspace
= get_frame_program_space (frame
);
4872 insert_step_resume_breakpoint_at_sal (gdbarch
,
4873 sr_sal
, null_frame_id
);
4876 /* Set a breakpoint at callee's return address (the address
4877 at which the caller will resume). */
4878 insert_step_resume_breakpoint_at_caller (frame
);
4884 /* Reverse stepping through solib trampolines. */
4886 if (execution_direction
== EXEC_REVERSE
4887 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
4889 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4890 || (ecs
->stop_func_start
== 0
4891 && in_solib_dynsym_resolve_code (stop_pc
)))
4893 /* Any solib trampoline code can be handled in reverse
4894 by simply continuing to single-step. We have already
4895 executed the solib function (backwards), and a few
4896 steps will take us back through the trampoline to the
4901 else if (in_solib_dynsym_resolve_code (stop_pc
))
4903 /* Stepped backward into the solib dynsym resolver.
4904 Set a breakpoint at its start and continue, then
4905 one more step will take us out. */
4906 struct symtab_and_line sr_sal
;
4909 sr_sal
.pc
= ecs
->stop_func_start
;
4910 sr_sal
.pspace
= get_frame_program_space (frame
);
4911 insert_step_resume_breakpoint_at_sal (gdbarch
,
4912 sr_sal
, null_frame_id
);
4918 /* If we're in the return path from a shared library trampoline,
4919 we want to proceed through the trampoline when stepping. */
4920 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4921 stop_pc
, ecs
->stop_func_name
))
4923 /* Determine where this trampoline returns. */
4924 CORE_ADDR real_stop_pc
;
4926 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4929 fprintf_unfiltered (gdb_stdlog
,
4930 "infrun: stepped into solib return tramp\n");
4932 /* Only proceed through if we know where it's going. */
4935 /* And put the step-breakpoint there and go until there. */
4936 struct symtab_and_line sr_sal
;
4938 init_sal (&sr_sal
); /* initialize to zeroes */
4939 sr_sal
.pc
= real_stop_pc
;
4940 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4941 sr_sal
.pspace
= get_frame_program_space (frame
);
4943 /* Do not specify what the fp should be when we stop since
4944 on some machines the prologue is where the new fp value
4946 insert_step_resume_breakpoint_at_sal (gdbarch
,
4947 sr_sal
, null_frame_id
);
4949 /* Restart without fiddling with the step ranges or
4956 stop_pc_sal
= find_pc_line (stop_pc
, 0);
4958 /* NOTE: tausq/2004-05-24: This if block used to be done before all
4959 the trampoline processing logic, however, there are some trampolines
4960 that have no names, so we should do trampoline handling first. */
4961 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4962 && ecs
->stop_func_name
== NULL
4963 && stop_pc_sal
.line
== 0)
4966 fprintf_unfiltered (gdb_stdlog
,
4967 "infrun: stepped into undebuggable function\n");
4969 /* The inferior just stepped into, or returned to, an
4970 undebuggable function (where there is no debugging information
4971 and no line number corresponding to the address where the
4972 inferior stopped). Since we want to skip this kind of code,
4973 we keep going until the inferior returns from this
4974 function - unless the user has asked us not to (via
4975 set step-mode) or we no longer know how to get back
4976 to the call site. */
4977 if (step_stop_if_no_debug
4978 || !frame_id_p (frame_unwind_caller_id (frame
)))
4980 /* If we have no line number and the step-stop-if-no-debug
4981 is set, we stop the step so that the user has a chance to
4982 switch in assembly mode. */
4983 ecs
->event_thread
->control
.stop_step
= 1;
4984 print_end_stepping_range_reason ();
4985 stop_stepping (ecs
);
4990 /* Set a breakpoint at callee's return address (the address
4991 at which the caller will resume). */
4992 insert_step_resume_breakpoint_at_caller (frame
);
4998 if (ecs
->event_thread
->control
.step_range_end
== 1)
5000 /* It is stepi or nexti. We always want to stop stepping after
5003 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5004 ecs
->event_thread
->control
.stop_step
= 1;
5005 print_end_stepping_range_reason ();
5006 stop_stepping (ecs
);
5010 if (stop_pc_sal
.line
== 0)
5012 /* We have no line number information. That means to stop
5013 stepping (does this always happen right after one instruction,
5014 when we do "s" in a function with no line numbers,
5015 or can this happen as a result of a return or longjmp?). */
5017 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5018 ecs
->event_thread
->control
.stop_step
= 1;
5019 print_end_stepping_range_reason ();
5020 stop_stepping (ecs
);
5024 /* Look for "calls" to inlined functions, part one. If the inline
5025 frame machinery detected some skipped call sites, we have entered
5026 a new inline function. */
5028 if (frame_id_eq (get_frame_id (get_current_frame ()),
5029 ecs
->event_thread
->control
.step_frame_id
)
5030 && inline_skipped_frames (ecs
->ptid
))
5032 struct symtab_and_line call_sal
;
5035 fprintf_unfiltered (gdb_stdlog
,
5036 "infrun: stepped into inlined function\n");
5038 find_frame_sal (get_current_frame (), &call_sal
);
5040 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5042 /* For "step", we're going to stop. But if the call site
5043 for this inlined function is on the same source line as
5044 we were previously stepping, go down into the function
5045 first. Otherwise stop at the call site. */
5047 if (call_sal
.line
== ecs
->event_thread
->current_line
5048 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5049 step_into_inline_frame (ecs
->ptid
);
5051 ecs
->event_thread
->control
.stop_step
= 1;
5052 print_end_stepping_range_reason ();
5053 stop_stepping (ecs
);
5058 /* For "next", we should stop at the call site if it is on a
5059 different source line. Otherwise continue through the
5060 inlined function. */
5061 if (call_sal
.line
== ecs
->event_thread
->current_line
5062 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5066 ecs
->event_thread
->control
.stop_step
= 1;
5067 print_end_stepping_range_reason ();
5068 stop_stepping (ecs
);
5074 /* Look for "calls" to inlined functions, part two. If we are still
5075 in the same real function we were stepping through, but we have
5076 to go further up to find the exact frame ID, we are stepping
5077 through a more inlined call beyond its call site. */
5079 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5080 && !frame_id_eq (get_frame_id (get_current_frame ()),
5081 ecs
->event_thread
->control
.step_frame_id
)
5082 && stepped_in_from (get_current_frame (),
5083 ecs
->event_thread
->control
.step_frame_id
))
5086 fprintf_unfiltered (gdb_stdlog
,
5087 "infrun: stepping through inlined function\n");
5089 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5093 ecs
->event_thread
->control
.stop_step
= 1;
5094 print_end_stepping_range_reason ();
5095 stop_stepping (ecs
);
5100 if ((stop_pc
== stop_pc_sal
.pc
)
5101 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5102 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5104 /* We are at the start of a different line. So stop. Note that
5105 we don't stop if we step into the middle of a different line.
5106 That is said to make things like for (;;) statements work
5109 fprintf_unfiltered (gdb_stdlog
,
5110 "infrun: stepped to a different line\n");
5111 ecs
->event_thread
->control
.stop_step
= 1;
5112 print_end_stepping_range_reason ();
5113 stop_stepping (ecs
);
5117 /* We aren't done stepping.
5119 Optimize by setting the stepping range to the line.
5120 (We might not be in the original line, but if we entered a
5121 new line in mid-statement, we continue stepping. This makes
5122 things like for(;;) statements work better.) */
5124 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5125 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5126 set_step_info (frame
, stop_pc_sal
);
5129 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5133 /* Is thread TP in the middle of single-stepping? */
5136 currently_stepping (struct thread_info
*tp
)
5138 return ((tp
->control
.step_range_end
5139 && tp
->control
.step_resume_breakpoint
== NULL
)
5140 || tp
->control
.trap_expected
5141 || bpstat_should_step ());
5144 /* Returns true if any thread *but* the one passed in "data" is in the
5145 middle of stepping or of handling a "next". */
5148 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
5153 return (tp
->control
.step_range_end
5154 || tp
->control
.trap_expected
);
5157 /* Inferior has stepped into a subroutine call with source code that
5158 we should not step over. Do step to the first line of code in
5162 handle_step_into_function (struct gdbarch
*gdbarch
,
5163 struct execution_control_state
*ecs
)
5166 struct symtab_and_line stop_func_sal
, sr_sal
;
5168 fill_in_stop_func (gdbarch
, ecs
);
5170 s
= find_pc_symtab (stop_pc
);
5171 if (s
&& s
->language
!= language_asm
)
5172 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5173 ecs
->stop_func_start
);
5175 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5176 /* Use the step_resume_break to step until the end of the prologue,
5177 even if that involves jumps (as it seems to on the vax under
5179 /* If the prologue ends in the middle of a source line, continue to
5180 the end of that source line (if it is still within the function).
5181 Otherwise, just go to end of prologue. */
5182 if (stop_func_sal
.end
5183 && stop_func_sal
.pc
!= ecs
->stop_func_start
5184 && stop_func_sal
.end
< ecs
->stop_func_end
)
5185 ecs
->stop_func_start
= stop_func_sal
.end
;
5187 /* Architectures which require breakpoint adjustment might not be able
5188 to place a breakpoint at the computed address. If so, the test
5189 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5190 ecs->stop_func_start to an address at which a breakpoint may be
5191 legitimately placed.
5193 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5194 made, GDB will enter an infinite loop when stepping through
5195 optimized code consisting of VLIW instructions which contain
5196 subinstructions corresponding to different source lines. On
5197 FR-V, it's not permitted to place a breakpoint on any but the
5198 first subinstruction of a VLIW instruction. When a breakpoint is
5199 set, GDB will adjust the breakpoint address to the beginning of
5200 the VLIW instruction. Thus, we need to make the corresponding
5201 adjustment here when computing the stop address. */
5203 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5205 ecs
->stop_func_start
5206 = gdbarch_adjust_breakpoint_address (gdbarch
,
5207 ecs
->stop_func_start
);
5210 if (ecs
->stop_func_start
== stop_pc
)
5212 /* We are already there: stop now. */
5213 ecs
->event_thread
->control
.stop_step
= 1;
5214 print_end_stepping_range_reason ();
5215 stop_stepping (ecs
);
5220 /* Put the step-breakpoint there and go until there. */
5221 init_sal (&sr_sal
); /* initialize to zeroes */
5222 sr_sal
.pc
= ecs
->stop_func_start
;
5223 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5224 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5226 /* Do not specify what the fp should be when we stop since on
5227 some machines the prologue is where the new fp value is
5229 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5231 /* And make sure stepping stops right away then. */
5232 ecs
->event_thread
->control
.step_range_end
5233 = ecs
->event_thread
->control
.step_range_start
;
5238 /* Inferior has stepped backward into a subroutine call with source
5239 code that we should not step over. Do step to the beginning of the
5240 last line of code in it. */
5243 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5244 struct execution_control_state
*ecs
)
5247 struct symtab_and_line stop_func_sal
;
5249 fill_in_stop_func (gdbarch
, ecs
);
5251 s
= find_pc_symtab (stop_pc
);
5252 if (s
&& s
->language
!= language_asm
)
5253 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5254 ecs
->stop_func_start
);
5256 stop_func_sal
= find_pc_line (stop_pc
, 0);
5258 /* OK, we're just going to keep stepping here. */
5259 if (stop_func_sal
.pc
== stop_pc
)
5261 /* We're there already. Just stop stepping now. */
5262 ecs
->event_thread
->control
.stop_step
= 1;
5263 print_end_stepping_range_reason ();
5264 stop_stepping (ecs
);
5268 /* Else just reset the step range and keep going.
5269 No step-resume breakpoint, they don't work for
5270 epilogues, which can have multiple entry paths. */
5271 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5272 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5278 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5279 This is used to both functions and to skip over code. */
5282 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5283 struct symtab_and_line sr_sal
,
5284 struct frame_id sr_id
,
5285 enum bptype sr_type
)
5287 /* There should never be more than one step-resume or longjmp-resume
5288 breakpoint per thread, so we should never be setting a new
5289 step_resume_breakpoint when one is already active. */
5290 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5291 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5294 fprintf_unfiltered (gdb_stdlog
,
5295 "infrun: inserting step-resume breakpoint at %s\n",
5296 paddress (gdbarch
, sr_sal
.pc
));
5298 inferior_thread ()->control
.step_resume_breakpoint
5299 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5303 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5304 struct symtab_and_line sr_sal
,
5305 struct frame_id sr_id
)
5307 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5312 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5313 This is used to skip a potential signal handler.
5315 This is called with the interrupted function's frame. The signal
5316 handler, when it returns, will resume the interrupted function at
5320 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5322 struct symtab_and_line sr_sal
;
5323 struct gdbarch
*gdbarch
;
5325 gdb_assert (return_frame
!= NULL
);
5326 init_sal (&sr_sal
); /* initialize to zeros */
5328 gdbarch
= get_frame_arch (return_frame
);
5329 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5330 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5331 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5333 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5334 get_stack_frame_id (return_frame
),
5338 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5339 is used to skip a function after stepping into it (for "next" or if
5340 the called function has no debugging information).
5342 The current function has almost always been reached by single
5343 stepping a call or return instruction. NEXT_FRAME belongs to the
5344 current function, and the breakpoint will be set at the caller's
5347 This is a separate function rather than reusing
5348 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5349 get_prev_frame, which may stop prematurely (see the implementation
5350 of frame_unwind_caller_id for an example). */
5353 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5355 struct symtab_and_line sr_sal
;
5356 struct gdbarch
*gdbarch
;
5358 /* We shouldn't have gotten here if we don't know where the call site
5360 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5362 init_sal (&sr_sal
); /* initialize to zeros */
5364 gdbarch
= frame_unwind_caller_arch (next_frame
);
5365 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5366 frame_unwind_caller_pc (next_frame
));
5367 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5368 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5370 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5371 frame_unwind_caller_id (next_frame
));
5374 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5375 new breakpoint at the target of a jmp_buf. The handling of
5376 longjmp-resume uses the same mechanisms used for handling
5377 "step-resume" breakpoints. */
5380 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5382 /* There should never be more than one step-resume or longjmp-resume
5383 breakpoint per thread, so we should never be setting a new
5384 longjmp_resume_breakpoint when one is already active. */
5385 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5388 fprintf_unfiltered (gdb_stdlog
,
5389 "infrun: inserting longjmp-resume breakpoint at %s\n",
5390 paddress (gdbarch
, pc
));
5392 inferior_thread ()->control
.step_resume_breakpoint
=
5393 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5396 /* Insert an exception resume breakpoint. TP is the thread throwing
5397 the exception. The block B is the block of the unwinder debug hook
5398 function. FRAME is the frame corresponding to the call to this
5399 function. SYM is the symbol of the function argument holding the
5400 target PC of the exception. */
5403 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5405 struct frame_info
*frame
,
5408 struct gdb_exception e
;
5410 /* We want to ignore errors here. */
5411 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5413 struct symbol
*vsym
;
5414 struct value
*value
;
5416 struct breakpoint
*bp
;
5418 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5419 value
= read_var_value (vsym
, frame
);
5420 /* If the value was optimized out, revert to the old behavior. */
5421 if (! value_optimized_out (value
))
5423 handler
= value_as_address (value
);
5426 fprintf_unfiltered (gdb_stdlog
,
5427 "infrun: exception resume at %lx\n",
5428 (unsigned long) handler
);
5430 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5431 handler
, bp_exception_resume
);
5432 bp
->thread
= tp
->num
;
5433 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5438 /* This is called when an exception has been intercepted. Check to
5439 see whether the exception's destination is of interest, and if so,
5440 set an exception resume breakpoint there. */
5443 check_exception_resume (struct execution_control_state
*ecs
,
5444 struct frame_info
*frame
, struct symbol
*func
)
5446 struct gdb_exception e
;
5448 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5451 struct dict_iterator iter
;
5455 /* The exception breakpoint is a thread-specific breakpoint on
5456 the unwinder's debug hook, declared as:
5458 void _Unwind_DebugHook (void *cfa, void *handler);
5460 The CFA argument indicates the frame to which control is
5461 about to be transferred. HANDLER is the destination PC.
5463 We ignore the CFA and set a temporary breakpoint at HANDLER.
5464 This is not extremely efficient but it avoids issues in gdb
5465 with computing the DWARF CFA, and it also works even in weird
5466 cases such as throwing an exception from inside a signal
5469 b
= SYMBOL_BLOCK_VALUE (func
);
5470 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
5472 if (!SYMBOL_IS_ARGUMENT (sym
))
5479 insert_exception_resume_breakpoint (ecs
->event_thread
,
5488 stop_stepping (struct execution_control_state
*ecs
)
5491 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
5493 /* Let callers know we don't want to wait for the inferior anymore. */
5494 ecs
->wait_some_more
= 0;
5497 /* This function handles various cases where we need to continue
5498 waiting for the inferior. */
5499 /* (Used to be the keep_going: label in the old wait_for_inferior). */
5502 keep_going (struct execution_control_state
*ecs
)
5504 /* Make sure normal_stop is called if we get a QUIT handled before
5506 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
5508 /* Save the pc before execution, to compare with pc after stop. */
5509 ecs
->event_thread
->prev_pc
5510 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5512 /* If we did not do break;, it means we should keep running the
5513 inferior and not return to debugger. */
5515 if (ecs
->event_thread
->control
.trap_expected
5516 && ecs
->event_thread
->suspend
.stop_signal
!= TARGET_SIGNAL_TRAP
)
5518 /* We took a signal (which we are supposed to pass through to
5519 the inferior, else we'd not get here) and we haven't yet
5520 gotten our trap. Simply continue. */
5522 discard_cleanups (old_cleanups
);
5523 resume (currently_stepping (ecs
->event_thread
),
5524 ecs
->event_thread
->suspend
.stop_signal
);
5528 /* Either the trap was not expected, but we are continuing
5529 anyway (the user asked that this signal be passed to the
5532 The signal was SIGTRAP, e.g. it was our signal, but we
5533 decided we should resume from it.
5535 We're going to run this baby now!
5537 Note that insert_breakpoints won't try to re-insert
5538 already inserted breakpoints. Therefore, we don't
5539 care if breakpoints were already inserted, or not. */
5541 if (ecs
->event_thread
->stepping_over_breakpoint
)
5543 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
5545 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
5546 /* Since we can't do a displaced step, we have to remove
5547 the breakpoint while we step it. To keep things
5548 simple, we remove them all. */
5549 remove_breakpoints ();
5553 struct gdb_exception e
;
5555 /* Stop stepping when inserting breakpoints
5557 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5559 insert_breakpoints ();
5563 exception_print (gdb_stderr
, e
);
5564 stop_stepping (ecs
);
5569 ecs
->event_thread
->control
.trap_expected
5570 = ecs
->event_thread
->stepping_over_breakpoint
;
5572 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
5573 specifies that such a signal should be delivered to the
5576 Typically, this would occure when a user is debugging a
5577 target monitor on a simulator: the target monitor sets a
5578 breakpoint; the simulator encounters this break-point and
5579 halts the simulation handing control to GDB; GDB, noteing
5580 that the break-point isn't valid, returns control back to the
5581 simulator; the simulator then delivers the hardware
5582 equivalent of a SIGNAL_TRAP to the program being debugged. */
5584 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
5585 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5586 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
5588 discard_cleanups (old_cleanups
);
5589 resume (currently_stepping (ecs
->event_thread
),
5590 ecs
->event_thread
->suspend
.stop_signal
);
5593 prepare_to_wait (ecs
);
5596 /* This function normally comes after a resume, before
5597 handle_inferior_event exits. It takes care of any last bits of
5598 housekeeping, and sets the all-important wait_some_more flag. */
5601 prepare_to_wait (struct execution_control_state
*ecs
)
5604 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
5606 /* This is the old end of the while loop. Let everybody know we
5607 want to wait for the inferior some more and get called again
5609 ecs
->wait_some_more
= 1;
5612 /* Several print_*_reason functions to print why the inferior has stopped.
5613 We always print something when the inferior exits, or receives a signal.
5614 The rest of the cases are dealt with later on in normal_stop and
5615 print_it_typical. Ideally there should be a call to one of these
5616 print_*_reason functions functions from handle_inferior_event each time
5617 stop_stepping is called. */
5619 /* Print why the inferior has stopped.
5620 We are done with a step/next/si/ni command, print why the inferior has
5621 stopped. For now print nothing. Print a message only if not in the middle
5622 of doing a "step n" operation for n > 1. */
5625 print_end_stepping_range_reason (void)
5627 if ((!inferior_thread ()->step_multi
5628 || !inferior_thread ()->control
.stop_step
)
5629 && ui_out_is_mi_like_p (current_uiout
))
5630 ui_out_field_string (current_uiout
, "reason",
5631 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
5634 /* The inferior was terminated by a signal, print why it stopped. */
5637 print_signal_exited_reason (enum target_signal siggnal
)
5639 struct ui_out
*uiout
= current_uiout
;
5641 annotate_signalled ();
5642 if (ui_out_is_mi_like_p (uiout
))
5644 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
5645 ui_out_text (uiout
, "\nProgram terminated with signal ");
5646 annotate_signal_name ();
5647 ui_out_field_string (uiout
, "signal-name",
5648 target_signal_to_name (siggnal
));
5649 annotate_signal_name_end ();
5650 ui_out_text (uiout
, ", ");
5651 annotate_signal_string ();
5652 ui_out_field_string (uiout
, "signal-meaning",
5653 target_signal_to_string (siggnal
));
5654 annotate_signal_string_end ();
5655 ui_out_text (uiout
, ".\n");
5656 ui_out_text (uiout
, "The program no longer exists.\n");
5659 /* The inferior program is finished, print why it stopped. */
5662 print_exited_reason (int exitstatus
)
5664 struct inferior
*inf
= current_inferior ();
5665 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
5666 struct ui_out
*uiout
= current_uiout
;
5668 annotate_exited (exitstatus
);
5671 if (ui_out_is_mi_like_p (uiout
))
5672 ui_out_field_string (uiout
, "reason",
5673 async_reason_lookup (EXEC_ASYNC_EXITED
));
5674 ui_out_text (uiout
, "[Inferior ");
5675 ui_out_text (uiout
, plongest (inf
->num
));
5676 ui_out_text (uiout
, " (");
5677 ui_out_text (uiout
, pidstr
);
5678 ui_out_text (uiout
, ") exited with code ");
5679 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
5680 ui_out_text (uiout
, "]\n");
5684 if (ui_out_is_mi_like_p (uiout
))
5686 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
5687 ui_out_text (uiout
, "[Inferior ");
5688 ui_out_text (uiout
, plongest (inf
->num
));
5689 ui_out_text (uiout
, " (");
5690 ui_out_text (uiout
, pidstr
);
5691 ui_out_text (uiout
, ") exited normally]\n");
5693 /* Support the --return-child-result option. */
5694 return_child_result_value
= exitstatus
;
5697 /* Signal received, print why the inferior has stopped. The signal table
5698 tells us to print about it. */
5701 print_signal_received_reason (enum target_signal siggnal
)
5703 struct ui_out
*uiout
= current_uiout
;
5707 if (siggnal
== TARGET_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
5709 struct thread_info
*t
= inferior_thread ();
5711 ui_out_text (uiout
, "\n[");
5712 ui_out_field_string (uiout
, "thread-name",
5713 target_pid_to_str (t
->ptid
));
5714 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
5715 ui_out_text (uiout
, " stopped");
5719 ui_out_text (uiout
, "\nProgram received signal ");
5720 annotate_signal_name ();
5721 if (ui_out_is_mi_like_p (uiout
))
5723 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
5724 ui_out_field_string (uiout
, "signal-name",
5725 target_signal_to_name (siggnal
));
5726 annotate_signal_name_end ();
5727 ui_out_text (uiout
, ", ");
5728 annotate_signal_string ();
5729 ui_out_field_string (uiout
, "signal-meaning",
5730 target_signal_to_string (siggnal
));
5731 annotate_signal_string_end ();
5733 ui_out_text (uiout
, ".\n");
5736 /* Reverse execution: target ran out of history info, print why the inferior
5740 print_no_history_reason (void)
5742 ui_out_text (current_uiout
, "\nNo more reverse-execution history.\n");
5745 /* Here to return control to GDB when the inferior stops for real.
5746 Print appropriate messages, remove breakpoints, give terminal our modes.
5748 STOP_PRINT_FRAME nonzero means print the executing frame
5749 (pc, function, args, file, line number and line text).
5750 BREAKPOINTS_FAILED nonzero means stop was due to error
5751 attempting to insert breakpoints. */
5756 struct target_waitstatus last
;
5758 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
5760 get_last_target_status (&last_ptid
, &last
);
5762 /* If an exception is thrown from this point on, make sure to
5763 propagate GDB's knowledge of the executing state to the
5764 frontend/user running state. A QUIT is an easy exception to see
5765 here, so do this before any filtered output. */
5767 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
5768 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
5769 && last
.kind
!= TARGET_WAITKIND_EXITED
)
5770 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
5772 /* In non-stop mode, we don't want GDB to switch threads behind the
5773 user's back, to avoid races where the user is typing a command to
5774 apply to thread x, but GDB switches to thread y before the user
5775 finishes entering the command. */
5777 /* As with the notification of thread events, we want to delay
5778 notifying the user that we've switched thread context until
5779 the inferior actually stops.
5781 There's no point in saying anything if the inferior has exited.
5782 Note that SIGNALLED here means "exited with a signal", not
5783 "received a signal". */
5785 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
5786 && target_has_execution
5787 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5788 && last
.kind
!= TARGET_WAITKIND_EXITED
)
5790 target_terminal_ours_for_output ();
5791 printf_filtered (_("[Switching to %s]\n"),
5792 target_pid_to_str (inferior_ptid
));
5793 annotate_thread_changed ();
5794 previous_inferior_ptid
= inferior_ptid
;
5797 if (!breakpoints_always_inserted_mode () && target_has_execution
)
5799 if (remove_breakpoints ())
5801 target_terminal_ours_for_output ();
5802 printf_filtered (_("Cannot remove breakpoints because "
5803 "program is no longer writable.\nFurther "
5804 "execution is probably impossible.\n"));
5808 /* If an auto-display called a function and that got a signal,
5809 delete that auto-display to avoid an infinite recursion. */
5811 if (stopped_by_random_signal
)
5812 disable_current_display ();
5814 /* Don't print a message if in the middle of doing a "step n"
5815 operation for n > 1 */
5816 if (target_has_execution
5817 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5818 && last
.kind
!= TARGET_WAITKIND_EXITED
5819 && inferior_thread ()->step_multi
5820 && inferior_thread ()->control
.stop_step
)
5823 target_terminal_ours ();
5824 async_enable_stdin ();
5826 /* Set the current source location. This will also happen if we
5827 display the frame below, but the current SAL will be incorrect
5828 during a user hook-stop function. */
5829 if (has_stack_frames () && !stop_stack_dummy
)
5830 set_current_sal_from_frame (get_current_frame (), 1);
5832 /* Let the user/frontend see the threads as stopped. */
5833 do_cleanups (old_chain
);
5835 /* Look up the hook_stop and run it (CLI internally handles problem
5836 of stop_command's pre-hook not existing). */
5838 catch_errors (hook_stop_stub
, stop_command
,
5839 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
5841 if (!has_stack_frames ())
5844 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
5845 || last
.kind
== TARGET_WAITKIND_EXITED
)
5848 /* Select innermost stack frame - i.e., current frame is frame 0,
5849 and current location is based on that.
5850 Don't do this on return from a stack dummy routine,
5851 or if the program has exited. */
5853 if (!stop_stack_dummy
)
5855 select_frame (get_current_frame ());
5857 /* Print current location without a level number, if
5858 we have changed functions or hit a breakpoint.
5859 Print source line if we have one.
5860 bpstat_print() contains the logic deciding in detail
5861 what to print, based on the event(s) that just occurred. */
5863 /* If --batch-silent is enabled then there's no need to print the current
5864 source location, and to try risks causing an error message about
5865 missing source files. */
5866 if (stop_print_frame
&& !batch_silent
)
5870 int do_frame_printing
= 1;
5871 struct thread_info
*tp
= inferior_thread ();
5873 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
);
5877 /* If we had hit a shared library event breakpoint,
5878 bpstat_print would print out this message. If we hit
5879 an OS-level shared library event, do the same
5881 if (last
.kind
== TARGET_WAITKIND_LOADED
)
5883 printf_filtered (_("Stopped due to shared library event\n"));
5884 source_flag
= SRC_LINE
; /* something bogus */
5885 do_frame_printing
= 0;
5889 /* FIXME: cagney/2002-12-01: Given that a frame ID does
5890 (or should) carry around the function and does (or
5891 should) use that when doing a frame comparison. */
5892 if (tp
->control
.stop_step
5893 && frame_id_eq (tp
->control
.step_frame_id
,
5894 get_frame_id (get_current_frame ()))
5895 && step_start_function
== find_pc_function (stop_pc
))
5896 source_flag
= SRC_LINE
; /* Finished step, just
5897 print source line. */
5899 source_flag
= SRC_AND_LOC
; /* Print location and
5902 case PRINT_SRC_AND_LOC
:
5903 source_flag
= SRC_AND_LOC
; /* Print location and
5906 case PRINT_SRC_ONLY
:
5907 source_flag
= SRC_LINE
;
5910 source_flag
= SRC_LINE
; /* something bogus */
5911 do_frame_printing
= 0;
5914 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
5917 /* The behavior of this routine with respect to the source
5919 SRC_LINE: Print only source line
5920 LOCATION: Print only location
5921 SRC_AND_LOC: Print location and source line. */
5922 if (do_frame_printing
)
5923 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
5925 /* Display the auto-display expressions. */
5930 /* Save the function value return registers, if we care.
5931 We might be about to restore their previous contents. */
5932 if (inferior_thread ()->control
.proceed_to_finish
5933 && execution_direction
!= EXEC_REVERSE
)
5935 /* This should not be necessary. */
5937 regcache_xfree (stop_registers
);
5939 /* NB: The copy goes through to the target picking up the value of
5940 all the registers. */
5941 stop_registers
= regcache_dup (get_current_regcache ());
5944 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
5946 /* Pop the empty frame that contains the stack dummy.
5947 This also restores inferior state prior to the call
5948 (struct infcall_suspend_state). */
5949 struct frame_info
*frame
= get_current_frame ();
5951 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
5953 /* frame_pop() calls reinit_frame_cache as the last thing it
5954 does which means there's currently no selected frame. We
5955 don't need to re-establish a selected frame if the dummy call
5956 returns normally, that will be done by
5957 restore_infcall_control_state. However, we do have to handle
5958 the case where the dummy call is returning after being
5959 stopped (e.g. the dummy call previously hit a breakpoint).
5960 We can't know which case we have so just always re-establish
5961 a selected frame here. */
5962 select_frame (get_current_frame ());
5966 annotate_stopped ();
5968 /* Suppress the stop observer if we're in the middle of:
5970 - a step n (n > 1), as there still more steps to be done.
5972 - a "finish" command, as the observer will be called in
5973 finish_command_continuation, so it can include the inferior
5974 function's return value.
5976 - calling an inferior function, as we pretend we inferior didn't
5977 run at all. The return value of the call is handled by the
5978 expression evaluator, through call_function_by_hand. */
5980 if (!target_has_execution
5981 || last
.kind
== TARGET_WAITKIND_SIGNALLED
5982 || last
.kind
== TARGET_WAITKIND_EXITED
5983 || (!inferior_thread ()->step_multi
5984 && !(inferior_thread ()->control
.stop_bpstat
5985 && inferior_thread ()->control
.proceed_to_finish
)
5986 && !inferior_thread ()->control
.in_infcall
))
5988 if (!ptid_equal (inferior_ptid
, null_ptid
))
5989 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
5992 observer_notify_normal_stop (NULL
, stop_print_frame
);
5995 if (target_has_execution
)
5997 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
5998 && last
.kind
!= TARGET_WAITKIND_EXITED
)
5999 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6000 Delete any breakpoint that is to be deleted at the next stop. */
6001 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6004 /* Try to get rid of automatically added inferiors that are no
6005 longer needed. Keeping those around slows down things linearly.
6006 Note that this never removes the current inferior. */
6011 hook_stop_stub (void *cmd
)
6013 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6018 signal_stop_state (int signo
)
6020 return signal_stop
[signo
];
6024 signal_print_state (int signo
)
6026 return signal_print
[signo
];
6030 signal_pass_state (int signo
)
6032 return signal_program
[signo
];
6036 signal_cache_update (int signo
)
6040 for (signo
= 0; signo
< (int) TARGET_SIGNAL_LAST
; signo
++)
6041 signal_cache_update (signo
);
6046 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6047 && signal_print
[signo
] == 0
6048 && signal_program
[signo
] == 1);
6052 signal_stop_update (int signo
, int state
)
6054 int ret
= signal_stop
[signo
];
6056 signal_stop
[signo
] = state
;
6057 signal_cache_update (signo
);
6062 signal_print_update (int signo
, int state
)
6064 int ret
= signal_print
[signo
];
6066 signal_print
[signo
] = state
;
6067 signal_cache_update (signo
);
6072 signal_pass_update (int signo
, int state
)
6074 int ret
= signal_program
[signo
];
6076 signal_program
[signo
] = state
;
6077 signal_cache_update (signo
);
6082 sig_print_header (void)
6084 printf_filtered (_("Signal Stop\tPrint\tPass "
6085 "to program\tDescription\n"));
6089 sig_print_info (enum target_signal oursig
)
6091 const char *name
= target_signal_to_name (oursig
);
6092 int name_padding
= 13 - strlen (name
);
6094 if (name_padding
<= 0)
6097 printf_filtered ("%s", name
);
6098 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6099 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6100 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6101 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6102 printf_filtered ("%s\n", target_signal_to_string (oursig
));
6105 /* Specify how various signals in the inferior should be handled. */
6108 handle_command (char *args
, int from_tty
)
6111 int digits
, wordlen
;
6112 int sigfirst
, signum
, siglast
;
6113 enum target_signal oursig
;
6116 unsigned char *sigs
;
6117 struct cleanup
*old_chain
;
6121 error_no_arg (_("signal to handle"));
6124 /* Allocate and zero an array of flags for which signals to handle. */
6126 nsigs
= (int) TARGET_SIGNAL_LAST
;
6127 sigs
= (unsigned char *) alloca (nsigs
);
6128 memset (sigs
, 0, nsigs
);
6130 /* Break the command line up into args. */
6132 argv
= gdb_buildargv (args
);
6133 old_chain
= make_cleanup_freeargv (argv
);
6135 /* Walk through the args, looking for signal oursigs, signal names, and
6136 actions. Signal numbers and signal names may be interspersed with
6137 actions, with the actions being performed for all signals cumulatively
6138 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6140 while (*argv
!= NULL
)
6142 wordlen
= strlen (*argv
);
6143 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6147 sigfirst
= siglast
= -1;
6149 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6151 /* Apply action to all signals except those used by the
6152 debugger. Silently skip those. */
6155 siglast
= nsigs
- 1;
6157 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6159 SET_SIGS (nsigs
, sigs
, signal_stop
);
6160 SET_SIGS (nsigs
, sigs
, signal_print
);
6162 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6164 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6166 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6168 SET_SIGS (nsigs
, sigs
, signal_print
);
6170 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6172 SET_SIGS (nsigs
, sigs
, signal_program
);
6174 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6176 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6178 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6180 SET_SIGS (nsigs
, sigs
, signal_program
);
6182 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6184 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6185 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6187 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6189 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6191 else if (digits
> 0)
6193 /* It is numeric. The numeric signal refers to our own
6194 internal signal numbering from target.h, not to host/target
6195 signal number. This is a feature; users really should be
6196 using symbolic names anyway, and the common ones like
6197 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6199 sigfirst
= siglast
= (int)
6200 target_signal_from_command (atoi (*argv
));
6201 if ((*argv
)[digits
] == '-')
6204 target_signal_from_command (atoi ((*argv
) + digits
+ 1));
6206 if (sigfirst
> siglast
)
6208 /* Bet he didn't figure we'd think of this case... */
6216 oursig
= target_signal_from_name (*argv
);
6217 if (oursig
!= TARGET_SIGNAL_UNKNOWN
)
6219 sigfirst
= siglast
= (int) oursig
;
6223 /* Not a number and not a recognized flag word => complain. */
6224 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6228 /* If any signal numbers or symbol names were found, set flags for
6229 which signals to apply actions to. */
6231 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6233 switch ((enum target_signal
) signum
)
6235 case TARGET_SIGNAL_TRAP
:
6236 case TARGET_SIGNAL_INT
:
6237 if (!allsigs
&& !sigs
[signum
])
6239 if (query (_("%s is used by the debugger.\n\
6240 Are you sure you want to change it? "),
6241 target_signal_to_name ((enum target_signal
) signum
)))
6247 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6248 gdb_flush (gdb_stdout
);
6252 case TARGET_SIGNAL_0
:
6253 case TARGET_SIGNAL_DEFAULT
:
6254 case TARGET_SIGNAL_UNKNOWN
:
6255 /* Make sure that "all" doesn't print these. */
6266 for (signum
= 0; signum
< nsigs
; signum
++)
6269 signal_cache_update (-1);
6270 target_pass_signals ((int) TARGET_SIGNAL_LAST
, signal_pass
);
6274 /* Show the results. */
6275 sig_print_header ();
6276 for (; signum
< nsigs
; signum
++)
6278 sig_print_info (signum
);
6284 do_cleanups (old_chain
);
6288 xdb_handle_command (char *args
, int from_tty
)
6291 struct cleanup
*old_chain
;
6294 error_no_arg (_("xdb command"));
6296 /* Break the command line up into args. */
6298 argv
= gdb_buildargv (args
);
6299 old_chain
= make_cleanup_freeargv (argv
);
6300 if (argv
[1] != (char *) NULL
)
6305 bufLen
= strlen (argv
[0]) + 20;
6306 argBuf
= (char *) xmalloc (bufLen
);
6310 enum target_signal oursig
;
6312 oursig
= target_signal_from_name (argv
[0]);
6313 memset (argBuf
, 0, bufLen
);
6314 if (strcmp (argv
[1], "Q") == 0)
6315 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6318 if (strcmp (argv
[1], "s") == 0)
6320 if (!signal_stop
[oursig
])
6321 sprintf (argBuf
, "%s %s", argv
[0], "stop");
6323 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
6325 else if (strcmp (argv
[1], "i") == 0)
6327 if (!signal_program
[oursig
])
6328 sprintf (argBuf
, "%s %s", argv
[0], "pass");
6330 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
6332 else if (strcmp (argv
[1], "r") == 0)
6334 if (!signal_print
[oursig
])
6335 sprintf (argBuf
, "%s %s", argv
[0], "print");
6337 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6343 handle_command (argBuf
, from_tty
);
6345 printf_filtered (_("Invalid signal handling flag.\n"));
6350 do_cleanups (old_chain
);
6353 /* Print current contents of the tables set by the handle command.
6354 It is possible we should just be printing signals actually used
6355 by the current target (but for things to work right when switching
6356 targets, all signals should be in the signal tables). */
6359 signals_info (char *signum_exp
, int from_tty
)
6361 enum target_signal oursig
;
6363 sig_print_header ();
6367 /* First see if this is a symbol name. */
6368 oursig
= target_signal_from_name (signum_exp
);
6369 if (oursig
== TARGET_SIGNAL_UNKNOWN
)
6371 /* No, try numeric. */
6373 target_signal_from_command (parse_and_eval_long (signum_exp
));
6375 sig_print_info (oursig
);
6379 printf_filtered ("\n");
6380 /* These ugly casts brought to you by the native VAX compiler. */
6381 for (oursig
= TARGET_SIGNAL_FIRST
;
6382 (int) oursig
< (int) TARGET_SIGNAL_LAST
;
6383 oursig
= (enum target_signal
) ((int) oursig
+ 1))
6387 if (oursig
!= TARGET_SIGNAL_UNKNOWN
6388 && oursig
!= TARGET_SIGNAL_DEFAULT
&& oursig
!= TARGET_SIGNAL_0
)
6389 sig_print_info (oursig
);
6392 printf_filtered (_("\nUse the \"handle\" command "
6393 "to change these tables.\n"));
6396 /* Check if it makes sense to read $_siginfo from the current thread
6397 at this point. If not, throw an error. */
6400 validate_siginfo_access (void)
6402 /* No current inferior, no siginfo. */
6403 if (ptid_equal (inferior_ptid
, null_ptid
))
6404 error (_("No thread selected."));
6406 /* Don't try to read from a dead thread. */
6407 if (is_exited (inferior_ptid
))
6408 error (_("The current thread has terminated"));
6410 /* ... or from a spinning thread. */
6411 if (is_running (inferior_ptid
))
6412 error (_("Selected thread is running."));
6415 /* The $_siginfo convenience variable is a bit special. We don't know
6416 for sure the type of the value until we actually have a chance to
6417 fetch the data. The type can change depending on gdbarch, so it is
6418 also dependent on which thread you have selected.
6420 1. making $_siginfo be an internalvar that creates a new value on
6423 2. making the value of $_siginfo be an lval_computed value. */
6425 /* This function implements the lval_computed support for reading a
6429 siginfo_value_read (struct value
*v
)
6431 LONGEST transferred
;
6433 validate_siginfo_access ();
6436 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
6438 value_contents_all_raw (v
),
6440 TYPE_LENGTH (value_type (v
)));
6442 if (transferred
!= TYPE_LENGTH (value_type (v
)))
6443 error (_("Unable to read siginfo"));
6446 /* This function implements the lval_computed support for writing a
6450 siginfo_value_write (struct value
*v
, struct value
*fromval
)
6452 LONGEST transferred
;
6454 validate_siginfo_access ();
6456 transferred
= target_write (¤t_target
,
6457 TARGET_OBJECT_SIGNAL_INFO
,
6459 value_contents_all_raw (fromval
),
6461 TYPE_LENGTH (value_type (fromval
)));
6463 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
6464 error (_("Unable to write siginfo"));
6467 static const struct lval_funcs siginfo_value_funcs
=
6473 /* Return a new value with the correct type for the siginfo object of
6474 the current thread using architecture GDBARCH. Return a void value
6475 if there's no object available. */
6477 static struct value
*
6478 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
)
6480 if (target_has_stack
6481 && !ptid_equal (inferior_ptid
, null_ptid
)
6482 && gdbarch_get_siginfo_type_p (gdbarch
))
6484 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6486 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
6489 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
6493 /* infcall_suspend_state contains state about the program itself like its
6494 registers and any signal it received when it last stopped.
6495 This state must be restored regardless of how the inferior function call
6496 ends (either successfully, or after it hits a breakpoint or signal)
6497 if the program is to properly continue where it left off. */
6499 struct infcall_suspend_state
6501 struct thread_suspend_state thread_suspend
;
6502 struct inferior_suspend_state inferior_suspend
;
6506 struct regcache
*registers
;
6508 /* Format of SIGINFO_DATA or NULL if it is not present. */
6509 struct gdbarch
*siginfo_gdbarch
;
6511 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
6512 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
6513 content would be invalid. */
6514 gdb_byte
*siginfo_data
;
6517 struct infcall_suspend_state
*
6518 save_infcall_suspend_state (void)
6520 struct infcall_suspend_state
*inf_state
;
6521 struct thread_info
*tp
= inferior_thread ();
6522 struct inferior
*inf
= current_inferior ();
6523 struct regcache
*regcache
= get_current_regcache ();
6524 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6525 gdb_byte
*siginfo_data
= NULL
;
6527 if (gdbarch_get_siginfo_type_p (gdbarch
))
6529 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6530 size_t len
= TYPE_LENGTH (type
);
6531 struct cleanup
*back_to
;
6533 siginfo_data
= xmalloc (len
);
6534 back_to
= make_cleanup (xfree
, siginfo_data
);
6536 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6537 siginfo_data
, 0, len
) == len
)
6538 discard_cleanups (back_to
);
6541 /* Errors ignored. */
6542 do_cleanups (back_to
);
6543 siginfo_data
= NULL
;
6547 inf_state
= XZALLOC (struct infcall_suspend_state
);
6551 inf_state
->siginfo_gdbarch
= gdbarch
;
6552 inf_state
->siginfo_data
= siginfo_data
;
6555 inf_state
->thread_suspend
= tp
->suspend
;
6556 inf_state
->inferior_suspend
= inf
->suspend
;
6558 /* run_inferior_call will not use the signal due to its `proceed' call with
6559 TARGET_SIGNAL_0 anyway. */
6560 tp
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
6562 inf_state
->stop_pc
= stop_pc
;
6564 inf_state
->registers
= regcache_dup (regcache
);
6569 /* Restore inferior session state to INF_STATE. */
6572 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6574 struct thread_info
*tp
= inferior_thread ();
6575 struct inferior
*inf
= current_inferior ();
6576 struct regcache
*regcache
= get_current_regcache ();
6577 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6579 tp
->suspend
= inf_state
->thread_suspend
;
6580 inf
->suspend
= inf_state
->inferior_suspend
;
6582 stop_pc
= inf_state
->stop_pc
;
6584 if (inf_state
->siginfo_gdbarch
== gdbarch
)
6586 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6587 size_t len
= TYPE_LENGTH (type
);
6589 /* Errors ignored. */
6590 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6591 inf_state
->siginfo_data
, 0, len
);
6594 /* The inferior can be gone if the user types "print exit(0)"
6595 (and perhaps other times). */
6596 if (target_has_execution
)
6597 /* NB: The register write goes through to the target. */
6598 regcache_cpy (regcache
, inf_state
->registers
);
6600 discard_infcall_suspend_state (inf_state
);
6604 do_restore_infcall_suspend_state_cleanup (void *state
)
6606 restore_infcall_suspend_state (state
);
6610 make_cleanup_restore_infcall_suspend_state
6611 (struct infcall_suspend_state
*inf_state
)
6613 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
6617 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6619 regcache_xfree (inf_state
->registers
);
6620 xfree (inf_state
->siginfo_data
);
6625 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
6627 return inf_state
->registers
;
6630 /* infcall_control_state contains state regarding gdb's control of the
6631 inferior itself like stepping control. It also contains session state like
6632 the user's currently selected frame. */
6634 struct infcall_control_state
6636 struct thread_control_state thread_control
;
6637 struct inferior_control_state inferior_control
;
6640 enum stop_stack_kind stop_stack_dummy
;
6641 int stopped_by_random_signal
;
6642 int stop_after_trap
;
6644 /* ID if the selected frame when the inferior function call was made. */
6645 struct frame_id selected_frame_id
;
6648 /* Save all of the information associated with the inferior<==>gdb
6651 struct infcall_control_state
*
6652 save_infcall_control_state (void)
6654 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
6655 struct thread_info
*tp
= inferior_thread ();
6656 struct inferior
*inf
= current_inferior ();
6658 inf_status
->thread_control
= tp
->control
;
6659 inf_status
->inferior_control
= inf
->control
;
6661 tp
->control
.step_resume_breakpoint
= NULL
;
6662 tp
->control
.exception_resume_breakpoint
= NULL
;
6664 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
6665 chain. If caller's caller is walking the chain, they'll be happier if we
6666 hand them back the original chain when restore_infcall_control_state is
6668 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
6671 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
6672 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
6673 inf_status
->stop_after_trap
= stop_after_trap
;
6675 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
6681 restore_selected_frame (void *args
)
6683 struct frame_id
*fid
= (struct frame_id
*) args
;
6684 struct frame_info
*frame
;
6686 frame
= frame_find_by_id (*fid
);
6688 /* If inf_status->selected_frame_id is NULL, there was no previously
6692 warning (_("Unable to restore previously selected frame."));
6696 select_frame (frame
);
6701 /* Restore inferior session state to INF_STATUS. */
6704 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
6706 struct thread_info
*tp
= inferior_thread ();
6707 struct inferior
*inf
= current_inferior ();
6709 if (tp
->control
.step_resume_breakpoint
)
6710 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
6712 if (tp
->control
.exception_resume_breakpoint
)
6713 tp
->control
.exception_resume_breakpoint
->disposition
6714 = disp_del_at_next_stop
;
6716 /* Handle the bpstat_copy of the chain. */
6717 bpstat_clear (&tp
->control
.stop_bpstat
);
6719 tp
->control
= inf_status
->thread_control
;
6720 inf
->control
= inf_status
->inferior_control
;
6723 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
6724 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
6725 stop_after_trap
= inf_status
->stop_after_trap
;
6727 if (target_has_stack
)
6729 /* The point of catch_errors is that if the stack is clobbered,
6730 walking the stack might encounter a garbage pointer and
6731 error() trying to dereference it. */
6733 (restore_selected_frame
, &inf_status
->selected_frame_id
,
6734 "Unable to restore previously selected frame:\n",
6735 RETURN_MASK_ERROR
) == 0)
6736 /* Error in restoring the selected frame. Select the innermost
6738 select_frame (get_current_frame ());
6745 do_restore_infcall_control_state_cleanup (void *sts
)
6747 restore_infcall_control_state (sts
);
6751 make_cleanup_restore_infcall_control_state
6752 (struct infcall_control_state
*inf_status
)
6754 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
6758 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
6760 if (inf_status
->thread_control
.step_resume_breakpoint
)
6761 inf_status
->thread_control
.step_resume_breakpoint
->disposition
6762 = disp_del_at_next_stop
;
6764 if (inf_status
->thread_control
.exception_resume_breakpoint
)
6765 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
6766 = disp_del_at_next_stop
;
6768 /* See save_infcall_control_state for info on stop_bpstat. */
6769 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
6775 inferior_has_forked (ptid_t pid
, ptid_t
*child_pid
)
6777 struct target_waitstatus last
;
6780 get_last_target_status (&last_ptid
, &last
);
6782 if (last
.kind
!= TARGET_WAITKIND_FORKED
)
6785 if (!ptid_equal (last_ptid
, pid
))
6788 *child_pid
= last
.value
.related_pid
;
6793 inferior_has_vforked (ptid_t pid
, ptid_t
*child_pid
)
6795 struct target_waitstatus last
;
6798 get_last_target_status (&last_ptid
, &last
);
6800 if (last
.kind
!= TARGET_WAITKIND_VFORKED
)
6803 if (!ptid_equal (last_ptid
, pid
))
6806 *child_pid
= last
.value
.related_pid
;
6811 inferior_has_execd (ptid_t pid
, char **execd_pathname
)
6813 struct target_waitstatus last
;
6816 get_last_target_status (&last_ptid
, &last
);
6818 if (last
.kind
!= TARGET_WAITKIND_EXECD
)
6821 if (!ptid_equal (last_ptid
, pid
))
6824 *execd_pathname
= xstrdup (last
.value
.execd_pathname
);
6829 inferior_has_called_syscall (ptid_t pid
, int *syscall_number
)
6831 struct target_waitstatus last
;
6834 get_last_target_status (&last_ptid
, &last
);
6836 if (last
.kind
!= TARGET_WAITKIND_SYSCALL_ENTRY
&&
6837 last
.kind
!= TARGET_WAITKIND_SYSCALL_RETURN
)
6840 if (!ptid_equal (last_ptid
, pid
))
6843 *syscall_number
= last
.value
.syscall_number
;
6848 ptid_match (ptid_t ptid
, ptid_t filter
)
6850 if (ptid_equal (filter
, minus_one_ptid
))
6852 if (ptid_is_pid (filter
)
6853 && ptid_get_pid (ptid
) == ptid_get_pid (filter
))
6855 else if (ptid_equal (ptid
, filter
))
6861 /* restore_inferior_ptid() will be used by the cleanup machinery
6862 to restore the inferior_ptid value saved in a call to
6863 save_inferior_ptid(). */
6866 restore_inferior_ptid (void *arg
)
6868 ptid_t
*saved_ptid_ptr
= arg
;
6870 inferior_ptid
= *saved_ptid_ptr
;
6874 /* Save the value of inferior_ptid so that it may be restored by a
6875 later call to do_cleanups(). Returns the struct cleanup pointer
6876 needed for later doing the cleanup. */
6879 save_inferior_ptid (void)
6881 ptid_t
*saved_ptid_ptr
;
6883 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
6884 *saved_ptid_ptr
= inferior_ptid
;
6885 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
6889 /* User interface for reverse debugging:
6890 Set exec-direction / show exec-direction commands
6891 (returns error unless target implements to_set_exec_direction method). */
6893 int execution_direction
= EXEC_FORWARD
;
6894 static const char exec_forward
[] = "forward";
6895 static const char exec_reverse
[] = "reverse";
6896 static const char *exec_direction
= exec_forward
;
6897 static const char *exec_direction_names
[] = {
6904 set_exec_direction_func (char *args
, int from_tty
,
6905 struct cmd_list_element
*cmd
)
6907 if (target_can_execute_reverse
)
6909 if (!strcmp (exec_direction
, exec_forward
))
6910 execution_direction
= EXEC_FORWARD
;
6911 else if (!strcmp (exec_direction
, exec_reverse
))
6912 execution_direction
= EXEC_REVERSE
;
6916 exec_direction
= exec_forward
;
6917 error (_("Target does not support this operation."));
6922 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
6923 struct cmd_list_element
*cmd
, const char *value
)
6925 switch (execution_direction
) {
6927 fprintf_filtered (out
, _("Forward.\n"));
6930 fprintf_filtered (out
, _("Reverse.\n"));
6933 internal_error (__FILE__
, __LINE__
,
6934 _("bogus execution_direction value: %d"),
6935 (int) execution_direction
);
6939 /* User interface for non-stop mode. */
6944 set_non_stop (char *args
, int from_tty
,
6945 struct cmd_list_element
*c
)
6947 if (target_has_execution
)
6949 non_stop_1
= non_stop
;
6950 error (_("Cannot change this setting while the inferior is running."));
6953 non_stop
= non_stop_1
;
6957 show_non_stop (struct ui_file
*file
, int from_tty
,
6958 struct cmd_list_element
*c
, const char *value
)
6960 fprintf_filtered (file
,
6961 _("Controlling the inferior in non-stop mode is %s.\n"),
6966 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
6967 struct cmd_list_element
*c
, const char *value
)
6969 fprintf_filtered (file
, _("Resuming the execution of threads "
6970 "of all processes is %s.\n"), value
);
6974 _initialize_infrun (void)
6979 add_info ("signals", signals_info
, _("\
6980 What debugger does when program gets various signals.\n\
6981 Specify a signal as argument to print info on that signal only."));
6982 add_info_alias ("handle", "signals", 0);
6984 add_com ("handle", class_run
, handle_command
, _("\
6985 Specify how to handle a signal.\n\
6986 Args are signals and actions to apply to those signals.\n\
6987 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
6988 from 1-15 are allowed for compatibility with old versions of GDB.\n\
6989 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
6990 The special arg \"all\" is recognized to mean all signals except those\n\
6991 used by the debugger, typically SIGTRAP and SIGINT.\n\
6992 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
6993 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
6994 Stop means reenter debugger if this signal happens (implies print).\n\
6995 Print means print a message if this signal happens.\n\
6996 Pass means let program see this signal; otherwise program doesn't know.\n\
6997 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
6998 Pass and Stop may be combined."));
7001 add_com ("lz", class_info
, signals_info
, _("\
7002 What debugger does when program gets various signals.\n\
7003 Specify a signal as argument to print info on that signal only."));
7004 add_com ("z", class_run
, xdb_handle_command
, _("\
7005 Specify how to handle a signal.\n\
7006 Args are signals and actions to apply to those signals.\n\
7007 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7008 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7009 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7010 The special arg \"all\" is recognized to mean all signals except those\n\
7011 used by the debugger, typically SIGTRAP and SIGINT.\n\
7012 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7013 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7014 nopass), \"Q\" (noprint)\n\
7015 Stop means reenter debugger if this signal happens (implies print).\n\
7016 Print means print a message if this signal happens.\n\
7017 Pass means let program see this signal; otherwise program doesn't know.\n\
7018 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7019 Pass and Stop may be combined."));
7023 stop_command
= add_cmd ("stop", class_obscure
,
7024 not_just_help_class_command
, _("\
7025 There is no `stop' command, but you can set a hook on `stop'.\n\
7026 This allows you to set a list of commands to be run each time execution\n\
7027 of the program stops."), &cmdlist
);
7029 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7030 Set inferior debugging."), _("\
7031 Show inferior debugging."), _("\
7032 When non-zero, inferior specific debugging is enabled."),
7035 &setdebuglist
, &showdebuglist
);
7037 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7038 &debug_displaced
, _("\
7039 Set displaced stepping debugging."), _("\
7040 Show displaced stepping debugging."), _("\
7041 When non-zero, displaced stepping specific debugging is enabled."),
7043 show_debug_displaced
,
7044 &setdebuglist
, &showdebuglist
);
7046 add_setshow_boolean_cmd ("non-stop", no_class
,
7048 Set whether gdb controls the inferior in non-stop mode."), _("\
7049 Show whether gdb controls the inferior in non-stop mode."), _("\
7050 When debugging a multi-threaded program and this setting is\n\
7051 off (the default, also called all-stop mode), when one thread stops\n\
7052 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7053 all other threads in the program while you interact with the thread of\n\
7054 interest. When you continue or step a thread, you can allow the other\n\
7055 threads to run, or have them remain stopped, but while you inspect any\n\
7056 thread's state, all threads stop.\n\
7058 In non-stop mode, when one thread stops, other threads can continue\n\
7059 to run freely. You'll be able to step each thread independently,\n\
7060 leave it stopped or free to run as needed."),
7066 numsigs
= (int) TARGET_SIGNAL_LAST
;
7067 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7068 signal_print
= (unsigned char *)
7069 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7070 signal_program
= (unsigned char *)
7071 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7072 signal_pass
= (unsigned char *)
7073 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7074 for (i
= 0; i
< numsigs
; i
++)
7077 signal_print
[i
] = 1;
7078 signal_program
[i
] = 1;
7081 /* Signals caused by debugger's own actions
7082 should not be given to the program afterwards. */
7083 signal_program
[TARGET_SIGNAL_TRAP
] = 0;
7084 signal_program
[TARGET_SIGNAL_INT
] = 0;
7086 /* Signals that are not errors should not normally enter the debugger. */
7087 signal_stop
[TARGET_SIGNAL_ALRM
] = 0;
7088 signal_print
[TARGET_SIGNAL_ALRM
] = 0;
7089 signal_stop
[TARGET_SIGNAL_VTALRM
] = 0;
7090 signal_print
[TARGET_SIGNAL_VTALRM
] = 0;
7091 signal_stop
[TARGET_SIGNAL_PROF
] = 0;
7092 signal_print
[TARGET_SIGNAL_PROF
] = 0;
7093 signal_stop
[TARGET_SIGNAL_CHLD
] = 0;
7094 signal_print
[TARGET_SIGNAL_CHLD
] = 0;
7095 signal_stop
[TARGET_SIGNAL_IO
] = 0;
7096 signal_print
[TARGET_SIGNAL_IO
] = 0;
7097 signal_stop
[TARGET_SIGNAL_POLL
] = 0;
7098 signal_print
[TARGET_SIGNAL_POLL
] = 0;
7099 signal_stop
[TARGET_SIGNAL_URG
] = 0;
7100 signal_print
[TARGET_SIGNAL_URG
] = 0;
7101 signal_stop
[TARGET_SIGNAL_WINCH
] = 0;
7102 signal_print
[TARGET_SIGNAL_WINCH
] = 0;
7103 signal_stop
[TARGET_SIGNAL_PRIO
] = 0;
7104 signal_print
[TARGET_SIGNAL_PRIO
] = 0;
7106 /* These signals are used internally by user-level thread
7107 implementations. (See signal(5) on Solaris.) Like the above
7108 signals, a healthy program receives and handles them as part of
7109 its normal operation. */
7110 signal_stop
[TARGET_SIGNAL_LWP
] = 0;
7111 signal_print
[TARGET_SIGNAL_LWP
] = 0;
7112 signal_stop
[TARGET_SIGNAL_WAITING
] = 0;
7113 signal_print
[TARGET_SIGNAL_WAITING
] = 0;
7114 signal_stop
[TARGET_SIGNAL_CANCEL
] = 0;
7115 signal_print
[TARGET_SIGNAL_CANCEL
] = 0;
7117 /* Update cached state. */
7118 signal_cache_update (-1);
7120 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7121 &stop_on_solib_events
, _("\
7122 Set stopping for shared library events."), _("\
7123 Show stopping for shared library events."), _("\
7124 If nonzero, gdb will give control to the user when the dynamic linker\n\
7125 notifies gdb of shared library events. The most common event of interest\n\
7126 to the user would be loading/unloading of a new library."),
7128 show_stop_on_solib_events
,
7129 &setlist
, &showlist
);
7131 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7132 follow_fork_mode_kind_names
,
7133 &follow_fork_mode_string
, _("\
7134 Set debugger response to a program call of fork or vfork."), _("\
7135 Show debugger response to a program call of fork or vfork."), _("\
7136 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7137 parent - the original process is debugged after a fork\n\
7138 child - the new process is debugged after a fork\n\
7139 The unfollowed process will continue to run.\n\
7140 By default, the debugger will follow the parent process."),
7142 show_follow_fork_mode_string
,
7143 &setlist
, &showlist
);
7145 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7146 follow_exec_mode_names
,
7147 &follow_exec_mode_string
, _("\
7148 Set debugger response to a program call of exec."), _("\
7149 Show debugger response to a program call of exec."), _("\
7150 An exec call replaces the program image of a process.\n\
7152 follow-exec-mode can be:\n\
7154 new - the debugger creates a new inferior and rebinds the process\n\
7155 to this new inferior. The program the process was running before\n\
7156 the exec call can be restarted afterwards by restarting the original\n\
7159 same - the debugger keeps the process bound to the same inferior.\n\
7160 The new executable image replaces the previous executable loaded in\n\
7161 the inferior. Restarting the inferior after the exec call restarts\n\
7162 the executable the process was running after the exec call.\n\
7164 By default, the debugger will use the same inferior."),
7166 show_follow_exec_mode_string
,
7167 &setlist
, &showlist
);
7169 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7170 scheduler_enums
, &scheduler_mode
, _("\
7171 Set mode for locking scheduler during execution."), _("\
7172 Show mode for locking scheduler during execution."), _("\
7173 off == no locking (threads may preempt at any time)\n\
7174 on == full locking (no thread except the current thread may run)\n\
7175 step == scheduler locked during every single-step operation.\n\
7176 In this mode, no other thread may run during a step command.\n\
7177 Other threads may run while stepping over a function call ('next')."),
7178 set_schedlock_func
, /* traps on target vector */
7179 show_scheduler_mode
,
7180 &setlist
, &showlist
);
7182 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7183 Set mode for resuming threads of all processes."), _("\
7184 Show mode for resuming threads of all processes."), _("\
7185 When on, execution commands (such as 'continue' or 'next') resume all\n\
7186 threads of all processes. When off (which is the default), execution\n\
7187 commands only resume the threads of the current process. The set of\n\
7188 threads that are resumed is further refined by the scheduler-locking\n\
7189 mode (see help set scheduler-locking)."),
7191 show_schedule_multiple
,
7192 &setlist
, &showlist
);
7194 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7195 Set mode of the step operation."), _("\
7196 Show mode of the step operation."), _("\
7197 When set, doing a step over a function without debug line information\n\
7198 will stop at the first instruction of that function. Otherwise, the\n\
7199 function is skipped and the step command stops at a different source line."),
7201 show_step_stop_if_no_debug
,
7202 &setlist
, &showlist
);
7204 add_setshow_enum_cmd ("displaced-stepping", class_run
,
7205 can_use_displaced_stepping_enum
,
7206 &can_use_displaced_stepping
, _("\
7207 Set debugger's willingness to use displaced stepping."), _("\
7208 Show debugger's willingness to use displaced stepping."), _("\
7209 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7210 supported by the target architecture. If off, gdb will not use displaced\n\
7211 stepping to step over breakpoints, even if such is supported by the target\n\
7212 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7213 if the target architecture supports it and non-stop mode is active, but will not\n\
7214 use it in all-stop mode (see help set non-stop)."),
7216 show_can_use_displaced_stepping
,
7217 &setlist
, &showlist
);
7219 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7220 &exec_direction
, _("Set direction of execution.\n\
7221 Options are 'forward' or 'reverse'."),
7222 _("Show direction of execution (forward/reverse)."),
7223 _("Tells gdb whether to execute forward or backward."),
7224 set_exec_direction_func
, show_exec_direction_func
,
7225 &setlist
, &showlist
);
7227 /* Set/show detach-on-fork: user-settable mode. */
7229 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7230 Set whether gdb will detach the child of a fork."), _("\
7231 Show whether gdb will detach the child of a fork."), _("\
7232 Tells gdb whether to detach the child of a fork."),
7233 NULL
, NULL
, &setlist
, &showlist
);
7235 /* ptid initializations */
7236 inferior_ptid
= null_ptid
;
7237 target_last_wait_ptid
= minus_one_ptid
;
7239 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7240 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7241 observer_attach_thread_exit (infrun_thread_thread_exit
);
7242 observer_attach_inferior_exit (infrun_inferior_exit
);
7244 /* Explicitly create without lookup, since that tries to create a
7245 value with a void typed value, and when we get here, gdbarch
7246 isn't initialized yet. At this point, we're quite sure there
7247 isn't another convenience variable of the same name. */
7248 create_internalvar_type_lazy ("_siginfo", siginfo_make_value
);
7250 add_setshow_boolean_cmd ("observer", no_class
,
7251 &observer_mode_1
, _("\
7252 Set whether gdb controls the inferior in observer mode."), _("\
7253 Show whether gdb controls the inferior in observer mode."), _("\
7254 In observer mode, GDB can get data from the inferior, but not\n\
7255 affect its execution. Registers and memory may not be changed,\n\
7256 breakpoints may not be set, and the program cannot be interrupted\n\