1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2012 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 #include "gdb_string.h"
27 #include "exceptions.h"
28 #include "breakpoint.h"
32 #include "cli/cli-script.h"
34 #include "gdbthread.h"
46 #include "dictionary.h"
48 #include "gdb_assert.h"
49 #include "mi/mi-common.h"
50 #include "event-top.h"
52 #include "inline-frame.h"
54 #include "tracepoint.h"
55 #include "continuations.h"
60 #include "completer.h"
61 #include "target-descriptions.h"
63 /* Prototypes for local functions */
65 static void signals_info (char *, int);
67 static void handle_command (char *, int);
69 static void sig_print_info (enum gdb_signal
);
71 static void sig_print_header (void);
73 static void resume_cleanups (void *);
75 static int hook_stop_stub (void *);
77 static int restore_selected_frame (void *);
79 static int follow_fork (void);
81 static void set_schedlock_func (char *args
, int from_tty
,
82 struct cmd_list_element
*c
);
84 static int currently_stepping (struct thread_info
*tp
);
86 static int currently_stepping_or_nexting_callback (struct thread_info
*tp
,
89 static void xdb_handle_command (char *args
, int from_tty
);
91 static int prepare_to_proceed (int);
93 static void print_exited_reason (int exitstatus
);
95 static void print_signal_exited_reason (enum gdb_signal siggnal
);
97 static void print_no_history_reason (void);
99 static void print_signal_received_reason (enum gdb_signal siggnal
);
101 static void print_end_stepping_range_reason (void);
103 void _initialize_infrun (void);
105 void nullify_last_target_wait_ptid (void);
107 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
109 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
111 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
113 /* When set, stop the 'step' command if we enter a function which has
114 no line number information. The normal behavior is that we step
115 over such function. */
116 int step_stop_if_no_debug
= 0;
118 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
119 struct cmd_list_element
*c
, const char *value
)
121 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
124 /* In asynchronous mode, but simulating synchronous execution. */
126 int sync_execution
= 0;
128 /* wait_for_inferior and normal_stop use this to notify the user
129 when the inferior stopped in a different thread than it had been
132 static ptid_t previous_inferior_ptid
;
134 /* Default behavior is to detach newly forked processes (legacy). */
137 int debug_displaced
= 0;
139 show_debug_displaced (struct ui_file
*file
, int from_tty
,
140 struct cmd_list_element
*c
, const char *value
)
142 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
145 unsigned int debug_infrun
= 0;
147 show_debug_infrun (struct ui_file
*file
, int from_tty
,
148 struct cmd_list_element
*c
, const char *value
)
150 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
154 /* Support for disabling address space randomization. */
156 int disable_randomization
= 1;
159 show_disable_randomization (struct ui_file
*file
, int from_tty
,
160 struct cmd_list_element
*c
, const char *value
)
162 if (target_supports_disable_randomization ())
163 fprintf_filtered (file
,
164 _("Disabling randomization of debuggee's "
165 "virtual address space is %s.\n"),
168 fputs_filtered (_("Disabling randomization of debuggee's "
169 "virtual address space is unsupported on\n"
170 "this platform.\n"), file
);
174 set_disable_randomization (char *args
, int from_tty
,
175 struct cmd_list_element
*c
)
177 if (!target_supports_disable_randomization ())
178 error (_("Disabling randomization of debuggee's "
179 "virtual address space is unsupported on\n"
184 /* If the program uses ELF-style shared libraries, then calls to
185 functions in shared libraries go through stubs, which live in a
186 table called the PLT (Procedure Linkage Table). The first time the
187 function is called, the stub sends control to the dynamic linker,
188 which looks up the function's real address, patches the stub so
189 that future calls will go directly to the function, and then passes
190 control to the function.
192 If we are stepping at the source level, we don't want to see any of
193 this --- we just want to skip over the stub and the dynamic linker.
194 The simple approach is to single-step until control leaves the
197 However, on some systems (e.g., Red Hat's 5.2 distribution) the
198 dynamic linker calls functions in the shared C library, so you
199 can't tell from the PC alone whether the dynamic linker is still
200 running. In this case, we use a step-resume breakpoint to get us
201 past the dynamic linker, as if we were using "next" to step over a
204 in_solib_dynsym_resolve_code() says whether we're in the dynamic
205 linker code or not. Normally, this means we single-step. However,
206 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
207 address where we can place a step-resume breakpoint to get past the
208 linker's symbol resolution function.
210 in_solib_dynsym_resolve_code() can generally be implemented in a
211 pretty portable way, by comparing the PC against the address ranges
212 of the dynamic linker's sections.
214 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
215 it depends on internal details of the dynamic linker. It's usually
216 not too hard to figure out where to put a breakpoint, but it
217 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
218 sanity checking. If it can't figure things out, returning zero and
219 getting the (possibly confusing) stepping behavior is better than
220 signalling an error, which will obscure the change in the
223 /* This function returns TRUE if pc is the address of an instruction
224 that lies within the dynamic linker (such as the event hook, or the
227 This function must be used only when a dynamic linker event has
228 been caught, and the inferior is being stepped out of the hook, or
229 undefined results are guaranteed. */
231 #ifndef SOLIB_IN_DYNAMIC_LINKER
232 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
235 /* "Observer mode" is somewhat like a more extreme version of
236 non-stop, in which all GDB operations that might affect the
237 target's execution have been disabled. */
239 static int non_stop_1
= 0;
241 int observer_mode
= 0;
242 static int observer_mode_1
= 0;
245 set_observer_mode (char *args
, int from_tty
,
246 struct cmd_list_element
*c
)
248 extern int pagination_enabled
;
250 if (target_has_execution
)
252 observer_mode_1
= observer_mode
;
253 error (_("Cannot change this setting while the inferior is running."));
256 observer_mode
= observer_mode_1
;
258 may_write_registers
= !observer_mode
;
259 may_write_memory
= !observer_mode
;
260 may_insert_breakpoints
= !observer_mode
;
261 may_insert_tracepoints
= !observer_mode
;
262 /* We can insert fast tracepoints in or out of observer mode,
263 but enable them if we're going into this mode. */
265 may_insert_fast_tracepoints
= 1;
266 may_stop
= !observer_mode
;
267 update_target_permissions ();
269 /* Going *into* observer mode we must force non-stop, then
270 going out we leave it that way. */
273 target_async_permitted
= 1;
274 pagination_enabled
= 0;
275 non_stop
= non_stop_1
= 1;
279 printf_filtered (_("Observer mode is now %s.\n"),
280 (observer_mode
? "on" : "off"));
284 show_observer_mode (struct ui_file
*file
, int from_tty
,
285 struct cmd_list_element
*c
, const char *value
)
287 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
290 /* This updates the value of observer mode based on changes in
291 permissions. Note that we are deliberately ignoring the values of
292 may-write-registers and may-write-memory, since the user may have
293 reason to enable these during a session, for instance to turn on a
294 debugging-related global. */
297 update_observer_mode (void)
301 newval
= (!may_insert_breakpoints
302 && !may_insert_tracepoints
303 && may_insert_fast_tracepoints
307 /* Let the user know if things change. */
308 if (newval
!= observer_mode
)
309 printf_filtered (_("Observer mode is now %s.\n"),
310 (newval
? "on" : "off"));
312 observer_mode
= observer_mode_1
= newval
;
315 /* Tables of how to react to signals; the user sets them. */
317 static unsigned char *signal_stop
;
318 static unsigned char *signal_print
;
319 static unsigned char *signal_program
;
321 /* Table of signals that the target may silently handle.
322 This is automatically determined from the flags above,
323 and simply cached here. */
324 static unsigned char *signal_pass
;
326 #define SET_SIGS(nsigs,sigs,flags) \
328 int signum = (nsigs); \
329 while (signum-- > 0) \
330 if ((sigs)[signum]) \
331 (flags)[signum] = 1; \
334 #define UNSET_SIGS(nsigs,sigs,flags) \
336 int signum = (nsigs); \
337 while (signum-- > 0) \
338 if ((sigs)[signum]) \
339 (flags)[signum] = 0; \
342 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
343 this function is to avoid exporting `signal_program'. */
346 update_signals_program_target (void)
348 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
351 /* Value to pass to target_resume() to cause all threads to resume. */
353 #define RESUME_ALL minus_one_ptid
355 /* Command list pointer for the "stop" placeholder. */
357 static struct cmd_list_element
*stop_command
;
359 /* Function inferior was in as of last step command. */
361 static struct symbol
*step_start_function
;
363 /* Nonzero if we want to give control to the user when we're notified
364 of shared library events by the dynamic linker. */
365 int stop_on_solib_events
;
367 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
368 struct cmd_list_element
*c
, const char *value
)
370 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
374 /* Nonzero means expecting a trace trap
375 and should stop the inferior and return silently when it happens. */
379 /* Save register contents here when executing a "finish" command or are
380 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
381 Thus this contains the return value from the called function (assuming
382 values are returned in a register). */
384 struct regcache
*stop_registers
;
386 /* Nonzero after stop if current stack frame should be printed. */
388 static int stop_print_frame
;
390 /* This is a cached copy of the pid/waitstatus of the last event
391 returned by target_wait()/deprecated_target_wait_hook(). This
392 information is returned by get_last_target_status(). */
393 static ptid_t target_last_wait_ptid
;
394 static struct target_waitstatus target_last_waitstatus
;
396 static void context_switch (ptid_t ptid
);
398 void init_thread_stepping_state (struct thread_info
*tss
);
400 void init_infwait_state (void);
402 static const char follow_fork_mode_child
[] = "child";
403 static const char follow_fork_mode_parent
[] = "parent";
405 static const char *const follow_fork_mode_kind_names
[] = {
406 follow_fork_mode_child
,
407 follow_fork_mode_parent
,
411 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
413 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
414 struct cmd_list_element
*c
, const char *value
)
416 fprintf_filtered (file
,
417 _("Debugger response to a program "
418 "call of fork or vfork is \"%s\".\n"),
423 /* Tell the target to follow the fork we're stopped at. Returns true
424 if the inferior should be resumed; false, if the target for some
425 reason decided it's best not to resume. */
430 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
431 int should_resume
= 1;
432 struct thread_info
*tp
;
434 /* Copy user stepping state to the new inferior thread. FIXME: the
435 followed fork child thread should have a copy of most of the
436 parent thread structure's run control related fields, not just these.
437 Initialized to avoid "may be used uninitialized" warnings from gcc. */
438 struct breakpoint
*step_resume_breakpoint
= NULL
;
439 struct breakpoint
*exception_resume_breakpoint
= NULL
;
440 CORE_ADDR step_range_start
= 0;
441 CORE_ADDR step_range_end
= 0;
442 struct frame_id step_frame_id
= { 0 };
447 struct target_waitstatus wait_status
;
449 /* Get the last target status returned by target_wait(). */
450 get_last_target_status (&wait_ptid
, &wait_status
);
452 /* If not stopped at a fork event, then there's nothing else to
454 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
455 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
458 /* Check if we switched over from WAIT_PTID, since the event was
460 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
461 && !ptid_equal (inferior_ptid
, wait_ptid
))
463 /* We did. Switch back to WAIT_PTID thread, to tell the
464 target to follow it (in either direction). We'll
465 afterwards refuse to resume, and inform the user what
467 switch_to_thread (wait_ptid
);
472 tp
= inferior_thread ();
474 /* If there were any forks/vforks that were caught and are now to be
475 followed, then do so now. */
476 switch (tp
->pending_follow
.kind
)
478 case TARGET_WAITKIND_FORKED
:
479 case TARGET_WAITKIND_VFORKED
:
481 ptid_t parent
, child
;
483 /* If the user did a next/step, etc, over a fork call,
484 preserve the stepping state in the fork child. */
485 if (follow_child
&& should_resume
)
487 step_resume_breakpoint
= clone_momentary_breakpoint
488 (tp
->control
.step_resume_breakpoint
);
489 step_range_start
= tp
->control
.step_range_start
;
490 step_range_end
= tp
->control
.step_range_end
;
491 step_frame_id
= tp
->control
.step_frame_id
;
492 exception_resume_breakpoint
493 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
495 /* For now, delete the parent's sr breakpoint, otherwise,
496 parent/child sr breakpoints are considered duplicates,
497 and the child version will not be installed. Remove
498 this when the breakpoints module becomes aware of
499 inferiors and address spaces. */
500 delete_step_resume_breakpoint (tp
);
501 tp
->control
.step_range_start
= 0;
502 tp
->control
.step_range_end
= 0;
503 tp
->control
.step_frame_id
= null_frame_id
;
504 delete_exception_resume_breakpoint (tp
);
507 parent
= inferior_ptid
;
508 child
= tp
->pending_follow
.value
.related_pid
;
510 /* Tell the target to do whatever is necessary to follow
511 either parent or child. */
512 if (target_follow_fork (follow_child
))
514 /* Target refused to follow, or there's some other reason
515 we shouldn't resume. */
520 /* This pending follow fork event is now handled, one way
521 or another. The previous selected thread may be gone
522 from the lists by now, but if it is still around, need
523 to clear the pending follow request. */
524 tp
= find_thread_ptid (parent
);
526 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
528 /* This makes sure we don't try to apply the "Switched
529 over from WAIT_PID" logic above. */
530 nullify_last_target_wait_ptid ();
532 /* If we followed the child, switch to it... */
535 switch_to_thread (child
);
537 /* ... and preserve the stepping state, in case the
538 user was stepping over the fork call. */
541 tp
= inferior_thread ();
542 tp
->control
.step_resume_breakpoint
543 = step_resume_breakpoint
;
544 tp
->control
.step_range_start
= step_range_start
;
545 tp
->control
.step_range_end
= step_range_end
;
546 tp
->control
.step_frame_id
= step_frame_id
;
547 tp
->control
.exception_resume_breakpoint
548 = exception_resume_breakpoint
;
552 /* If we get here, it was because we're trying to
553 resume from a fork catchpoint, but, the user
554 has switched threads away from the thread that
555 forked. In that case, the resume command
556 issued is most likely not applicable to the
557 child, so just warn, and refuse to resume. */
558 warning (_("Not resuming: switched threads "
559 "before following fork child.\n"));
562 /* Reset breakpoints in the child as appropriate. */
563 follow_inferior_reset_breakpoints ();
566 switch_to_thread (parent
);
570 case TARGET_WAITKIND_SPURIOUS
:
571 /* Nothing to follow. */
574 internal_error (__FILE__
, __LINE__
,
575 "Unexpected pending_follow.kind %d\n",
576 tp
->pending_follow
.kind
);
580 return should_resume
;
584 follow_inferior_reset_breakpoints (void)
586 struct thread_info
*tp
= inferior_thread ();
588 /* Was there a step_resume breakpoint? (There was if the user
589 did a "next" at the fork() call.) If so, explicitly reset its
592 step_resumes are a form of bp that are made to be per-thread.
593 Since we created the step_resume bp when the parent process
594 was being debugged, and now are switching to the child process,
595 from the breakpoint package's viewpoint, that's a switch of
596 "threads". We must update the bp's notion of which thread
597 it is for, or it'll be ignored when it triggers. */
599 if (tp
->control
.step_resume_breakpoint
)
600 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
602 if (tp
->control
.exception_resume_breakpoint
)
603 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
605 /* Reinsert all breakpoints in the child. The user may have set
606 breakpoints after catching the fork, in which case those
607 were never set in the child, but only in the parent. This makes
608 sure the inserted breakpoints match the breakpoint list. */
610 breakpoint_re_set ();
611 insert_breakpoints ();
614 /* The child has exited or execed: resume threads of the parent the
615 user wanted to be executing. */
618 proceed_after_vfork_done (struct thread_info
*thread
,
621 int pid
= * (int *) arg
;
623 if (ptid_get_pid (thread
->ptid
) == pid
624 && is_running (thread
->ptid
)
625 && !is_executing (thread
->ptid
)
626 && !thread
->stop_requested
627 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
630 fprintf_unfiltered (gdb_stdlog
,
631 "infrun: resuming vfork parent thread %s\n",
632 target_pid_to_str (thread
->ptid
));
634 switch_to_thread (thread
->ptid
);
635 clear_proceed_status ();
636 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
, 0);
642 /* Called whenever we notice an exec or exit event, to handle
643 detaching or resuming a vfork parent. */
646 handle_vfork_child_exec_or_exit (int exec
)
648 struct inferior
*inf
= current_inferior ();
650 if (inf
->vfork_parent
)
652 int resume_parent
= -1;
654 /* This exec or exit marks the end of the shared memory region
655 between the parent and the child. If the user wanted to
656 detach from the parent, now is the time. */
658 if (inf
->vfork_parent
->pending_detach
)
660 struct thread_info
*tp
;
661 struct cleanup
*old_chain
;
662 struct program_space
*pspace
;
663 struct address_space
*aspace
;
665 /* follow-fork child, detach-on-fork on. */
667 inf
->vfork_parent
->pending_detach
= 0;
671 /* If we're handling a child exit, then inferior_ptid
672 points at the inferior's pid, not to a thread. */
673 old_chain
= save_inferior_ptid ();
674 save_current_program_space ();
675 save_current_inferior ();
678 old_chain
= save_current_space_and_thread ();
680 /* We're letting loose of the parent. */
681 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
682 switch_to_thread (tp
->ptid
);
684 /* We're about to detach from the parent, which implicitly
685 removes breakpoints from its address space. There's a
686 catch here: we want to reuse the spaces for the child,
687 but, parent/child are still sharing the pspace at this
688 point, although the exec in reality makes the kernel give
689 the child a fresh set of new pages. The problem here is
690 that the breakpoints module being unaware of this, would
691 likely chose the child process to write to the parent
692 address space. Swapping the child temporarily away from
693 the spaces has the desired effect. Yes, this is "sort
696 pspace
= inf
->pspace
;
697 aspace
= inf
->aspace
;
701 if (debug_infrun
|| info_verbose
)
703 target_terminal_ours ();
706 fprintf_filtered (gdb_stdlog
,
707 "Detaching vfork parent process "
708 "%d after child exec.\n",
709 inf
->vfork_parent
->pid
);
711 fprintf_filtered (gdb_stdlog
,
712 "Detaching vfork parent process "
713 "%d after child exit.\n",
714 inf
->vfork_parent
->pid
);
717 target_detach (NULL
, 0);
720 inf
->pspace
= pspace
;
721 inf
->aspace
= aspace
;
723 do_cleanups (old_chain
);
727 /* We're staying attached to the parent, so, really give the
728 child a new address space. */
729 inf
->pspace
= add_program_space (maybe_new_address_space ());
730 inf
->aspace
= inf
->pspace
->aspace
;
732 set_current_program_space (inf
->pspace
);
734 resume_parent
= inf
->vfork_parent
->pid
;
736 /* Break the bonds. */
737 inf
->vfork_parent
->vfork_child
= NULL
;
741 struct cleanup
*old_chain
;
742 struct program_space
*pspace
;
744 /* If this is a vfork child exiting, then the pspace and
745 aspaces were shared with the parent. Since we're
746 reporting the process exit, we'll be mourning all that is
747 found in the address space, and switching to null_ptid,
748 preparing to start a new inferior. But, since we don't
749 want to clobber the parent's address/program spaces, we
750 go ahead and create a new one for this exiting
753 /* Switch to null_ptid, so that clone_program_space doesn't want
754 to read the selected frame of a dead process. */
755 old_chain
= save_inferior_ptid ();
756 inferior_ptid
= null_ptid
;
758 /* This inferior is dead, so avoid giving the breakpoints
759 module the option to write through to it (cloning a
760 program space resets breakpoints). */
763 pspace
= add_program_space (maybe_new_address_space ());
764 set_current_program_space (pspace
);
766 inf
->symfile_flags
= SYMFILE_NO_READ
;
767 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
768 inf
->pspace
= pspace
;
769 inf
->aspace
= pspace
->aspace
;
771 /* Put back inferior_ptid. We'll continue mourning this
773 do_cleanups (old_chain
);
775 resume_parent
= inf
->vfork_parent
->pid
;
776 /* Break the bonds. */
777 inf
->vfork_parent
->vfork_child
= NULL
;
780 inf
->vfork_parent
= NULL
;
782 gdb_assert (current_program_space
== inf
->pspace
);
784 if (non_stop
&& resume_parent
!= -1)
786 /* If the user wanted the parent to be running, let it go
788 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
791 fprintf_unfiltered (gdb_stdlog
,
792 "infrun: resuming vfork parent process %d\n",
795 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
797 do_cleanups (old_chain
);
802 /* Enum strings for "set|show displaced-stepping". */
804 static const char follow_exec_mode_new
[] = "new";
805 static const char follow_exec_mode_same
[] = "same";
806 static const char *const follow_exec_mode_names
[] =
808 follow_exec_mode_new
,
809 follow_exec_mode_same
,
813 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
815 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
816 struct cmd_list_element
*c
, const char *value
)
818 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
821 /* EXECD_PATHNAME is assumed to be non-NULL. */
824 follow_exec (ptid_t pid
, char *execd_pathname
)
826 struct thread_info
*th
= inferior_thread ();
827 struct inferior
*inf
= current_inferior ();
829 /* This is an exec event that we actually wish to pay attention to.
830 Refresh our symbol table to the newly exec'd program, remove any
833 If there are breakpoints, they aren't really inserted now,
834 since the exec() transformed our inferior into a fresh set
837 We want to preserve symbolic breakpoints on the list, since
838 we have hopes that they can be reset after the new a.out's
839 symbol table is read.
841 However, any "raw" breakpoints must be removed from the list
842 (e.g., the solib bp's), since their address is probably invalid
845 And, we DON'T want to call delete_breakpoints() here, since
846 that may write the bp's "shadow contents" (the instruction
847 value that was overwritten witha TRAP instruction). Since
848 we now have a new a.out, those shadow contents aren't valid. */
850 mark_breakpoints_out ();
852 update_breakpoints_after_exec ();
854 /* If there was one, it's gone now. We cannot truly step-to-next
855 statement through an exec(). */
856 th
->control
.step_resume_breakpoint
= NULL
;
857 th
->control
.exception_resume_breakpoint
= NULL
;
858 th
->control
.step_range_start
= 0;
859 th
->control
.step_range_end
= 0;
861 /* The target reports the exec event to the main thread, even if
862 some other thread does the exec, and even if the main thread was
863 already stopped --- if debugging in non-stop mode, it's possible
864 the user had the main thread held stopped in the previous image
865 --- release it now. This is the same behavior as step-over-exec
866 with scheduler-locking on in all-stop mode. */
867 th
->stop_requested
= 0;
869 /* What is this a.out's name? */
870 printf_unfiltered (_("%s is executing new program: %s\n"),
871 target_pid_to_str (inferior_ptid
),
874 /* We've followed the inferior through an exec. Therefore, the
875 inferior has essentially been killed & reborn. */
877 gdb_flush (gdb_stdout
);
879 breakpoint_init_inferior (inf_execd
);
881 if (gdb_sysroot
&& *gdb_sysroot
)
883 char *name
= alloca (strlen (gdb_sysroot
)
884 + strlen (execd_pathname
)
887 strcpy (name
, gdb_sysroot
);
888 strcat (name
, execd_pathname
);
889 execd_pathname
= name
;
892 /* Reset the shared library package. This ensures that we get a
893 shlib event when the child reaches "_start", at which point the
894 dld will have had a chance to initialize the child. */
895 /* Also, loading a symbol file below may trigger symbol lookups, and
896 we don't want those to be satisfied by the libraries of the
897 previous incarnation of this process. */
898 no_shared_libraries (NULL
, 0);
900 if (follow_exec_mode_string
== follow_exec_mode_new
)
902 struct program_space
*pspace
;
904 /* The user wants to keep the old inferior and program spaces
905 around. Create a new fresh one, and switch to it. */
907 inf
= add_inferior (current_inferior ()->pid
);
908 pspace
= add_program_space (maybe_new_address_space ());
909 inf
->pspace
= pspace
;
910 inf
->aspace
= pspace
->aspace
;
912 exit_inferior_num_silent (current_inferior ()->num
);
914 set_current_inferior (inf
);
915 set_current_program_space (pspace
);
919 /* The old description may no longer be fit for the new image.
920 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
921 old description; we'll read a new one below. No need to do
922 this on "follow-exec-mode new", as the old inferior stays
923 around (its description is later cleared/refetched on
925 target_clear_description ();
928 gdb_assert (current_program_space
== inf
->pspace
);
930 /* That a.out is now the one to use. */
931 exec_file_attach (execd_pathname
, 0);
933 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
934 (Position Independent Executable) main symbol file will get applied by
935 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
936 the breakpoints with the zero displacement. */
938 symbol_file_add (execd_pathname
,
940 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
943 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
944 set_initial_language ();
946 /* If the target can specify a description, read it. Must do this
947 after flipping to the new executable (because the target supplied
948 description must be compatible with the executable's
949 architecture, and the old executable may e.g., be 32-bit, while
950 the new one 64-bit), and before anything involving memory or
952 target_find_description ();
954 #ifdef SOLIB_CREATE_INFERIOR_HOOK
955 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid
));
957 solib_create_inferior_hook (0);
960 jit_inferior_created_hook ();
962 breakpoint_re_set ();
964 /* Reinsert all breakpoints. (Those which were symbolic have
965 been reset to the proper address in the new a.out, thanks
966 to symbol_file_command...). */
967 insert_breakpoints ();
969 /* The next resume of this inferior should bring it to the shlib
970 startup breakpoints. (If the user had also set bp's on
971 "main" from the old (parent) process, then they'll auto-
972 matically get reset there in the new process.). */
975 /* Non-zero if we just simulating a single-step. This is needed
976 because we cannot remove the breakpoints in the inferior process
977 until after the `wait' in `wait_for_inferior'. */
978 static int singlestep_breakpoints_inserted_p
= 0;
980 /* The thread we inserted single-step breakpoints for. */
981 static ptid_t singlestep_ptid
;
983 /* PC when we started this single-step. */
984 static CORE_ADDR singlestep_pc
;
986 /* If another thread hit the singlestep breakpoint, we save the original
987 thread here so that we can resume single-stepping it later. */
988 static ptid_t saved_singlestep_ptid
;
989 static int stepping_past_singlestep_breakpoint
;
991 /* If not equal to null_ptid, this means that after stepping over breakpoint
992 is finished, we need to switch to deferred_step_ptid, and step it.
994 The use case is when one thread has hit a breakpoint, and then the user
995 has switched to another thread and issued 'step'. We need to step over
996 breakpoint in the thread which hit the breakpoint, but then continue
997 stepping the thread user has selected. */
998 static ptid_t deferred_step_ptid
;
1000 /* Displaced stepping. */
1002 /* In non-stop debugging mode, we must take special care to manage
1003 breakpoints properly; in particular, the traditional strategy for
1004 stepping a thread past a breakpoint it has hit is unsuitable.
1005 'Displaced stepping' is a tactic for stepping one thread past a
1006 breakpoint it has hit while ensuring that other threads running
1007 concurrently will hit the breakpoint as they should.
1009 The traditional way to step a thread T off a breakpoint in a
1010 multi-threaded program in all-stop mode is as follows:
1012 a0) Initially, all threads are stopped, and breakpoints are not
1014 a1) We single-step T, leaving breakpoints uninserted.
1015 a2) We insert breakpoints, and resume all threads.
1017 In non-stop debugging, however, this strategy is unsuitable: we
1018 don't want to have to stop all threads in the system in order to
1019 continue or step T past a breakpoint. Instead, we use displaced
1022 n0) Initially, T is stopped, other threads are running, and
1023 breakpoints are inserted.
1024 n1) We copy the instruction "under" the breakpoint to a separate
1025 location, outside the main code stream, making any adjustments
1026 to the instruction, register, and memory state as directed by
1028 n2) We single-step T over the instruction at its new location.
1029 n3) We adjust the resulting register and memory state as directed
1030 by T's architecture. This includes resetting T's PC to point
1031 back into the main instruction stream.
1034 This approach depends on the following gdbarch methods:
1036 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1037 indicate where to copy the instruction, and how much space must
1038 be reserved there. We use these in step n1.
1040 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1041 address, and makes any necessary adjustments to the instruction,
1042 register contents, and memory. We use this in step n1.
1044 - gdbarch_displaced_step_fixup adjusts registers and memory after
1045 we have successfuly single-stepped the instruction, to yield the
1046 same effect the instruction would have had if we had executed it
1047 at its original address. We use this in step n3.
1049 - gdbarch_displaced_step_free_closure provides cleanup.
1051 The gdbarch_displaced_step_copy_insn and
1052 gdbarch_displaced_step_fixup functions must be written so that
1053 copying an instruction with gdbarch_displaced_step_copy_insn,
1054 single-stepping across the copied instruction, and then applying
1055 gdbarch_displaced_insn_fixup should have the same effects on the
1056 thread's memory and registers as stepping the instruction in place
1057 would have. Exactly which responsibilities fall to the copy and
1058 which fall to the fixup is up to the author of those functions.
1060 See the comments in gdbarch.sh for details.
1062 Note that displaced stepping and software single-step cannot
1063 currently be used in combination, although with some care I think
1064 they could be made to. Software single-step works by placing
1065 breakpoints on all possible subsequent instructions; if the
1066 displaced instruction is a PC-relative jump, those breakpoints
1067 could fall in very strange places --- on pages that aren't
1068 executable, or at addresses that are not proper instruction
1069 boundaries. (We do generally let other threads run while we wait
1070 to hit the software single-step breakpoint, and they might
1071 encounter such a corrupted instruction.) One way to work around
1072 this would be to have gdbarch_displaced_step_copy_insn fully
1073 simulate the effect of PC-relative instructions (and return NULL)
1074 on architectures that use software single-stepping.
1076 In non-stop mode, we can have independent and simultaneous step
1077 requests, so more than one thread may need to simultaneously step
1078 over a breakpoint. The current implementation assumes there is
1079 only one scratch space per process. In this case, we have to
1080 serialize access to the scratch space. If thread A wants to step
1081 over a breakpoint, but we are currently waiting for some other
1082 thread to complete a displaced step, we leave thread A stopped and
1083 place it in the displaced_step_request_queue. Whenever a displaced
1084 step finishes, we pick the next thread in the queue and start a new
1085 displaced step operation on it. See displaced_step_prepare and
1086 displaced_step_fixup for details. */
1088 struct displaced_step_request
1091 struct displaced_step_request
*next
;
1094 /* Per-inferior displaced stepping state. */
1095 struct displaced_step_inferior_state
1097 /* Pointer to next in linked list. */
1098 struct displaced_step_inferior_state
*next
;
1100 /* The process this displaced step state refers to. */
1103 /* A queue of pending displaced stepping requests. One entry per
1104 thread that needs to do a displaced step. */
1105 struct displaced_step_request
*step_request_queue
;
1107 /* If this is not null_ptid, this is the thread carrying out a
1108 displaced single-step in process PID. This thread's state will
1109 require fixing up once it has completed its step. */
1112 /* The architecture the thread had when we stepped it. */
1113 struct gdbarch
*step_gdbarch
;
1115 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1116 for post-step cleanup. */
1117 struct displaced_step_closure
*step_closure
;
1119 /* The address of the original instruction, and the copy we
1121 CORE_ADDR step_original
, step_copy
;
1123 /* Saved contents of copy area. */
1124 gdb_byte
*step_saved_copy
;
1127 /* The list of states of processes involved in displaced stepping
1129 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1131 /* Get the displaced stepping state of process PID. */
1133 static struct displaced_step_inferior_state
*
1134 get_displaced_stepping_state (int pid
)
1136 struct displaced_step_inferior_state
*state
;
1138 for (state
= displaced_step_inferior_states
;
1140 state
= state
->next
)
1141 if (state
->pid
== pid
)
1147 /* Add a new displaced stepping state for process PID to the displaced
1148 stepping state list, or return a pointer to an already existing
1149 entry, if it already exists. Never returns NULL. */
1151 static struct displaced_step_inferior_state
*
1152 add_displaced_stepping_state (int pid
)
1154 struct displaced_step_inferior_state
*state
;
1156 for (state
= displaced_step_inferior_states
;
1158 state
= state
->next
)
1159 if (state
->pid
== pid
)
1162 state
= xcalloc (1, sizeof (*state
));
1164 state
->next
= displaced_step_inferior_states
;
1165 displaced_step_inferior_states
= state
;
1170 /* If inferior is in displaced stepping, and ADDR equals to starting address
1171 of copy area, return corresponding displaced_step_closure. Otherwise,
1174 struct displaced_step_closure
*
1175 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1177 struct displaced_step_inferior_state
*displaced
1178 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1180 /* If checking the mode of displaced instruction in copy area. */
1181 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1182 && (displaced
->step_copy
== addr
))
1183 return displaced
->step_closure
;
1188 /* Remove the displaced stepping state of process PID. */
1191 remove_displaced_stepping_state (int pid
)
1193 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1195 gdb_assert (pid
!= 0);
1197 it
= displaced_step_inferior_states
;
1198 prev_next_p
= &displaced_step_inferior_states
;
1203 *prev_next_p
= it
->next
;
1208 prev_next_p
= &it
->next
;
1214 infrun_inferior_exit (struct inferior
*inf
)
1216 remove_displaced_stepping_state (inf
->pid
);
1219 /* If ON, and the architecture supports it, GDB will use displaced
1220 stepping to step over breakpoints. If OFF, or if the architecture
1221 doesn't support it, GDB will instead use the traditional
1222 hold-and-step approach. If AUTO (which is the default), GDB will
1223 decide which technique to use to step over breakpoints depending on
1224 which of all-stop or non-stop mode is active --- displaced stepping
1225 in non-stop mode; hold-and-step in all-stop mode. */
1227 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1230 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1231 struct cmd_list_element
*c
,
1234 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1235 fprintf_filtered (file
,
1236 _("Debugger's willingness to use displaced stepping "
1237 "to step over breakpoints is %s (currently %s).\n"),
1238 value
, non_stop
? "on" : "off");
1240 fprintf_filtered (file
,
1241 _("Debugger's willingness to use displaced stepping "
1242 "to step over breakpoints is %s.\n"), value
);
1245 /* Return non-zero if displaced stepping can/should be used to step
1246 over breakpoints. */
1249 use_displaced_stepping (struct gdbarch
*gdbarch
)
1251 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
&& non_stop
)
1252 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1253 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1254 && !RECORD_IS_USED
);
1257 /* Clean out any stray displaced stepping state. */
1259 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1261 /* Indicate that there is no cleanup pending. */
1262 displaced
->step_ptid
= null_ptid
;
1264 if (displaced
->step_closure
)
1266 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1267 displaced
->step_closure
);
1268 displaced
->step_closure
= NULL
;
1273 displaced_step_clear_cleanup (void *arg
)
1275 struct displaced_step_inferior_state
*state
= arg
;
1277 displaced_step_clear (state
);
1280 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1282 displaced_step_dump_bytes (struct ui_file
*file
,
1283 const gdb_byte
*buf
,
1288 for (i
= 0; i
< len
; i
++)
1289 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1290 fputs_unfiltered ("\n", file
);
1293 /* Prepare to single-step, using displaced stepping.
1295 Note that we cannot use displaced stepping when we have a signal to
1296 deliver. If we have a signal to deliver and an instruction to step
1297 over, then after the step, there will be no indication from the
1298 target whether the thread entered a signal handler or ignored the
1299 signal and stepped over the instruction successfully --- both cases
1300 result in a simple SIGTRAP. In the first case we mustn't do a
1301 fixup, and in the second case we must --- but we can't tell which.
1302 Comments in the code for 'random signals' in handle_inferior_event
1303 explain how we handle this case instead.
1305 Returns 1 if preparing was successful -- this thread is going to be
1306 stepped now; or 0 if displaced stepping this thread got queued. */
1308 displaced_step_prepare (ptid_t ptid
)
1310 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1311 struct regcache
*regcache
= get_thread_regcache (ptid
);
1312 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1313 CORE_ADDR original
, copy
;
1315 struct displaced_step_closure
*closure
;
1316 struct displaced_step_inferior_state
*displaced
;
1319 /* We should never reach this function if the architecture does not
1320 support displaced stepping. */
1321 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1323 /* We have to displaced step one thread at a time, as we only have
1324 access to a single scratch space per inferior. */
1326 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1328 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1330 /* Already waiting for a displaced step to finish. Defer this
1331 request and place in queue. */
1332 struct displaced_step_request
*req
, *new_req
;
1334 if (debug_displaced
)
1335 fprintf_unfiltered (gdb_stdlog
,
1336 "displaced: defering step of %s\n",
1337 target_pid_to_str (ptid
));
1339 new_req
= xmalloc (sizeof (*new_req
));
1340 new_req
->ptid
= ptid
;
1341 new_req
->next
= NULL
;
1343 if (displaced
->step_request_queue
)
1345 for (req
= displaced
->step_request_queue
;
1349 req
->next
= new_req
;
1352 displaced
->step_request_queue
= new_req
;
1358 if (debug_displaced
)
1359 fprintf_unfiltered (gdb_stdlog
,
1360 "displaced: stepping %s now\n",
1361 target_pid_to_str (ptid
));
1364 displaced_step_clear (displaced
);
1366 old_cleanups
= save_inferior_ptid ();
1367 inferior_ptid
= ptid
;
1369 original
= regcache_read_pc (regcache
);
1371 copy
= gdbarch_displaced_step_location (gdbarch
);
1372 len
= gdbarch_max_insn_length (gdbarch
);
1374 /* Save the original contents of the copy area. */
1375 displaced
->step_saved_copy
= xmalloc (len
);
1376 ignore_cleanups
= make_cleanup (free_current_contents
,
1377 &displaced
->step_saved_copy
);
1378 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1380 throw_error (MEMORY_ERROR
,
1381 _("Error accessing memory address %s (%s) for "
1382 "displaced-stepping scratch space."),
1383 paddress (gdbarch
, copy
), safe_strerror (status
));
1384 if (debug_displaced
)
1386 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1387 paddress (gdbarch
, copy
));
1388 displaced_step_dump_bytes (gdb_stdlog
,
1389 displaced
->step_saved_copy
,
1393 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1394 original
, copy
, regcache
);
1396 /* We don't support the fully-simulated case at present. */
1397 gdb_assert (closure
);
1399 /* Save the information we need to fix things up if the step
1401 displaced
->step_ptid
= ptid
;
1402 displaced
->step_gdbarch
= gdbarch
;
1403 displaced
->step_closure
= closure
;
1404 displaced
->step_original
= original
;
1405 displaced
->step_copy
= copy
;
1407 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1409 /* Resume execution at the copy. */
1410 regcache_write_pc (regcache
, copy
);
1412 discard_cleanups (ignore_cleanups
);
1414 do_cleanups (old_cleanups
);
1416 if (debug_displaced
)
1417 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1418 paddress (gdbarch
, copy
));
1424 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1425 const gdb_byte
*myaddr
, int len
)
1427 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1429 inferior_ptid
= ptid
;
1430 write_memory (memaddr
, myaddr
, len
);
1431 do_cleanups (ptid_cleanup
);
1434 /* Restore the contents of the copy area for thread PTID. */
1437 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1440 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1442 write_memory_ptid (ptid
, displaced
->step_copy
,
1443 displaced
->step_saved_copy
, len
);
1444 if (debug_displaced
)
1445 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1446 target_pid_to_str (ptid
),
1447 paddress (displaced
->step_gdbarch
,
1448 displaced
->step_copy
));
1452 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1454 struct cleanup
*old_cleanups
;
1455 struct displaced_step_inferior_state
*displaced
1456 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1458 /* Was any thread of this process doing a displaced step? */
1459 if (displaced
== NULL
)
1462 /* Was this event for the pid we displaced? */
1463 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1464 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1467 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1469 displaced_step_restore (displaced
, displaced
->step_ptid
);
1471 /* Did the instruction complete successfully? */
1472 if (signal
== GDB_SIGNAL_TRAP
)
1474 /* Fix up the resulting state. */
1475 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1476 displaced
->step_closure
,
1477 displaced
->step_original
,
1478 displaced
->step_copy
,
1479 get_thread_regcache (displaced
->step_ptid
));
1483 /* Since the instruction didn't complete, all we can do is
1485 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1486 CORE_ADDR pc
= regcache_read_pc (regcache
);
1488 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1489 regcache_write_pc (regcache
, pc
);
1492 do_cleanups (old_cleanups
);
1494 displaced
->step_ptid
= null_ptid
;
1496 /* Are there any pending displaced stepping requests? If so, run
1497 one now. Leave the state object around, since we're likely to
1498 need it again soon. */
1499 while (displaced
->step_request_queue
)
1501 struct displaced_step_request
*head
;
1503 struct regcache
*regcache
;
1504 struct gdbarch
*gdbarch
;
1505 CORE_ADDR actual_pc
;
1506 struct address_space
*aspace
;
1508 head
= displaced
->step_request_queue
;
1510 displaced
->step_request_queue
= head
->next
;
1513 context_switch (ptid
);
1515 regcache
= get_thread_regcache (ptid
);
1516 actual_pc
= regcache_read_pc (regcache
);
1517 aspace
= get_regcache_aspace (regcache
);
1519 if (breakpoint_here_p (aspace
, actual_pc
))
1521 if (debug_displaced
)
1522 fprintf_unfiltered (gdb_stdlog
,
1523 "displaced: stepping queued %s now\n",
1524 target_pid_to_str (ptid
));
1526 displaced_step_prepare (ptid
);
1528 gdbarch
= get_regcache_arch (regcache
);
1530 if (debug_displaced
)
1532 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
1535 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1536 paddress (gdbarch
, actual_pc
));
1537 read_memory (actual_pc
, buf
, sizeof (buf
));
1538 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1541 if (gdbarch_displaced_step_hw_singlestep (gdbarch
,
1542 displaced
->step_closure
))
1543 target_resume (ptid
, 1, GDB_SIGNAL_0
);
1545 target_resume (ptid
, 0, GDB_SIGNAL_0
);
1547 /* Done, we're stepping a thread. */
1553 struct thread_info
*tp
= inferior_thread ();
1555 /* The breakpoint we were sitting under has since been
1557 tp
->control
.trap_expected
= 0;
1559 /* Go back to what we were trying to do. */
1560 step
= currently_stepping (tp
);
1562 if (debug_displaced
)
1563 fprintf_unfiltered (gdb_stdlog
,
1564 "displaced: breakpoint is gone: %s, step(%d)\n",
1565 target_pid_to_str (tp
->ptid
), step
);
1567 target_resume (ptid
, step
, GDB_SIGNAL_0
);
1568 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1570 /* This request was discarded. See if there's any other
1571 thread waiting for its turn. */
1576 /* Update global variables holding ptids to hold NEW_PTID if they were
1577 holding OLD_PTID. */
1579 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1581 struct displaced_step_request
*it
;
1582 struct displaced_step_inferior_state
*displaced
;
1584 if (ptid_equal (inferior_ptid
, old_ptid
))
1585 inferior_ptid
= new_ptid
;
1587 if (ptid_equal (singlestep_ptid
, old_ptid
))
1588 singlestep_ptid
= new_ptid
;
1590 if (ptid_equal (deferred_step_ptid
, old_ptid
))
1591 deferred_step_ptid
= new_ptid
;
1593 for (displaced
= displaced_step_inferior_states
;
1595 displaced
= displaced
->next
)
1597 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
1598 displaced
->step_ptid
= new_ptid
;
1600 for (it
= displaced
->step_request_queue
; it
; it
= it
->next
)
1601 if (ptid_equal (it
->ptid
, old_ptid
))
1602 it
->ptid
= new_ptid
;
1609 /* Things to clean up if we QUIT out of resume (). */
1611 resume_cleanups (void *ignore
)
1616 static const char schedlock_off
[] = "off";
1617 static const char schedlock_on
[] = "on";
1618 static const char schedlock_step
[] = "step";
1619 static const char *const scheduler_enums
[] = {
1625 static const char *scheduler_mode
= schedlock_off
;
1627 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1628 struct cmd_list_element
*c
, const char *value
)
1630 fprintf_filtered (file
,
1631 _("Mode for locking scheduler "
1632 "during execution is \"%s\".\n"),
1637 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1639 if (!target_can_lock_scheduler
)
1641 scheduler_mode
= schedlock_off
;
1642 error (_("Target '%s' cannot support this command."), target_shortname
);
1646 /* True if execution commands resume all threads of all processes by
1647 default; otherwise, resume only threads of the current inferior
1649 int sched_multi
= 0;
1651 /* Try to setup for software single stepping over the specified location.
1652 Return 1 if target_resume() should use hardware single step.
1654 GDBARCH the current gdbarch.
1655 PC the location to step over. */
1658 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1662 if (execution_direction
== EXEC_FORWARD
1663 && gdbarch_software_single_step_p (gdbarch
)
1664 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1667 /* Do not pull these breakpoints until after a `wait' in
1668 `wait_for_inferior'. */
1669 singlestep_breakpoints_inserted_p
= 1;
1670 singlestep_ptid
= inferior_ptid
;
1676 /* Return a ptid representing the set of threads that we will proceed,
1677 in the perspective of the user/frontend. We may actually resume
1678 fewer threads at first, e.g., if a thread is stopped at a
1679 breakpoint that needs stepping-off, but that should not be visible
1680 to the user/frontend, and neither should the frontend/user be
1681 allowed to proceed any of the threads that happen to be stopped for
1682 internal run control handling, if a previous command wanted them
1686 user_visible_resume_ptid (int step
)
1688 /* By default, resume all threads of all processes. */
1689 ptid_t resume_ptid
= RESUME_ALL
;
1691 /* Maybe resume only all threads of the current process. */
1692 if (!sched_multi
&& target_supports_multi_process ())
1694 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
1697 /* Maybe resume a single thread after all. */
1700 /* With non-stop mode on, threads are always handled
1702 resume_ptid
= inferior_ptid
;
1704 else if ((scheduler_mode
== schedlock_on
)
1705 || (scheduler_mode
== schedlock_step
1706 && (step
|| singlestep_breakpoints_inserted_p
)))
1708 /* User-settable 'scheduler' mode requires solo thread resume. */
1709 resume_ptid
= inferior_ptid
;
1715 /* Resume the inferior, but allow a QUIT. This is useful if the user
1716 wants to interrupt some lengthy single-stepping operation
1717 (for child processes, the SIGINT goes to the inferior, and so
1718 we get a SIGINT random_signal, but for remote debugging and perhaps
1719 other targets, that's not true).
1721 STEP nonzero if we should step (zero to continue instead).
1722 SIG is the signal to give the inferior (zero for none). */
1724 resume (int step
, enum gdb_signal sig
)
1726 int should_resume
= 1;
1727 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
1728 struct regcache
*regcache
= get_current_regcache ();
1729 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1730 struct thread_info
*tp
= inferior_thread ();
1731 CORE_ADDR pc
= regcache_read_pc (regcache
);
1732 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1736 if (current_inferior ()->waiting_for_vfork_done
)
1738 /* Don't try to single-step a vfork parent that is waiting for
1739 the child to get out of the shared memory region (by exec'ing
1740 or exiting). This is particularly important on software
1741 single-step archs, as the child process would trip on the
1742 software single step breakpoint inserted for the parent
1743 process. Since the parent will not actually execute any
1744 instruction until the child is out of the shared region (such
1745 are vfork's semantics), it is safe to simply continue it.
1746 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
1747 the parent, and tell it to `keep_going', which automatically
1748 re-sets it stepping. */
1750 fprintf_unfiltered (gdb_stdlog
,
1751 "infrun: resume : clear step\n");
1756 fprintf_unfiltered (gdb_stdlog
,
1757 "infrun: resume (step=%d, signal=%d), "
1758 "trap_expected=%d, current thread [%s] at %s\n",
1759 step
, sig
, tp
->control
.trap_expected
,
1760 target_pid_to_str (inferior_ptid
),
1761 paddress (gdbarch
, pc
));
1763 /* Normally, by the time we reach `resume', the breakpoints are either
1764 removed or inserted, as appropriate. The exception is if we're sitting
1765 at a permanent breakpoint; we need to step over it, but permanent
1766 breakpoints can't be removed. So we have to test for it here. */
1767 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
1769 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
1770 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
1773 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1774 how to step past a permanent breakpoint on this architecture. Try using\n\
1775 a command like `return' or `jump' to continue execution."));
1778 /* If enabled, step over breakpoints by executing a copy of the
1779 instruction at a different address.
1781 We can't use displaced stepping when we have a signal to deliver;
1782 the comments for displaced_step_prepare explain why. The
1783 comments in the handle_inferior event for dealing with 'random
1784 signals' explain what we do instead.
1786 We can't use displaced stepping when we are waiting for vfork_done
1787 event, displaced stepping breaks the vfork child similarly as single
1788 step software breakpoint. */
1789 if (use_displaced_stepping (gdbarch
)
1790 && (tp
->control
.trap_expected
1791 || (step
&& gdbarch_software_single_step_p (gdbarch
)))
1792 && sig
== GDB_SIGNAL_0
1793 && !current_inferior ()->waiting_for_vfork_done
)
1795 struct displaced_step_inferior_state
*displaced
;
1797 if (!displaced_step_prepare (inferior_ptid
))
1799 /* Got placed in displaced stepping queue. Will be resumed
1800 later when all the currently queued displaced stepping
1801 requests finish. The thread is not executing at this point,
1802 and the call to set_executing will be made later. But we
1803 need to call set_running here, since from frontend point of view,
1804 the thread is running. */
1805 set_running (inferior_ptid
, 1);
1806 discard_cleanups (old_cleanups
);
1810 /* Update pc to reflect the new address from which we will execute
1811 instructions due to displaced stepping. */
1812 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
1814 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1815 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
1816 displaced
->step_closure
);
1819 /* Do we need to do it the hard way, w/temp breakpoints? */
1821 step
= maybe_software_singlestep (gdbarch
, pc
);
1823 /* Currently, our software single-step implementation leads to different
1824 results than hardware single-stepping in one situation: when stepping
1825 into delivering a signal which has an associated signal handler,
1826 hardware single-step will stop at the first instruction of the handler,
1827 while software single-step will simply skip execution of the handler.
1829 For now, this difference in behavior is accepted since there is no
1830 easy way to actually implement single-stepping into a signal handler
1831 without kernel support.
1833 However, there is one scenario where this difference leads to follow-on
1834 problems: if we're stepping off a breakpoint by removing all breakpoints
1835 and then single-stepping. In this case, the software single-step
1836 behavior means that even if there is a *breakpoint* in the signal
1837 handler, GDB still would not stop.
1839 Fortunately, we can at least fix this particular issue. We detect
1840 here the case where we are about to deliver a signal while software
1841 single-stepping with breakpoints removed. In this situation, we
1842 revert the decisions to remove all breakpoints and insert single-
1843 step breakpoints, and instead we install a step-resume breakpoint
1844 at the current address, deliver the signal without stepping, and
1845 once we arrive back at the step-resume breakpoint, actually step
1846 over the breakpoint we originally wanted to step over. */
1847 if (singlestep_breakpoints_inserted_p
1848 && tp
->control
.trap_expected
&& sig
!= GDB_SIGNAL_0
)
1850 /* If we have nested signals or a pending signal is delivered
1851 immediately after a handler returns, might might already have
1852 a step-resume breakpoint set on the earlier handler. We cannot
1853 set another step-resume breakpoint; just continue on until the
1854 original breakpoint is hit. */
1855 if (tp
->control
.step_resume_breakpoint
== NULL
)
1857 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
1858 tp
->step_after_step_resume_breakpoint
= 1;
1861 remove_single_step_breakpoints ();
1862 singlestep_breakpoints_inserted_p
= 0;
1864 insert_breakpoints ();
1865 tp
->control
.trap_expected
= 0;
1872 /* If STEP is set, it's a request to use hardware stepping
1873 facilities. But in that case, we should never
1874 use singlestep breakpoint. */
1875 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1877 /* Decide the set of threads to ask the target to resume. Start
1878 by assuming everything will be resumed, than narrow the set
1879 by applying increasingly restricting conditions. */
1880 resume_ptid
= user_visible_resume_ptid (step
);
1882 /* Maybe resume a single thread after all. */
1883 if (singlestep_breakpoints_inserted_p
1884 && stepping_past_singlestep_breakpoint
)
1886 /* The situation here is as follows. In thread T1 we wanted to
1887 single-step. Lacking hardware single-stepping we've
1888 set breakpoint at the PC of the next instruction -- call it
1889 P. After resuming, we've hit that breakpoint in thread T2.
1890 Now we've removed original breakpoint, inserted breakpoint
1891 at P+1, and try to step to advance T2 past breakpoint.
1892 We need to step only T2, as if T1 is allowed to freely run,
1893 it can run past P, and if other threads are allowed to run,
1894 they can hit breakpoint at P+1, and nested hits of single-step
1895 breakpoints is not something we'd want -- that's complicated
1896 to support, and has no value. */
1897 resume_ptid
= inferior_ptid
;
1899 else if ((step
|| singlestep_breakpoints_inserted_p
)
1900 && tp
->control
.trap_expected
)
1902 /* We're allowing a thread to run past a breakpoint it has
1903 hit, by single-stepping the thread with the breakpoint
1904 removed. In which case, we need to single-step only this
1905 thread, and keep others stopped, as they can miss this
1906 breakpoint if allowed to run.
1908 The current code actually removes all breakpoints when
1909 doing this, not just the one being stepped over, so if we
1910 let other threads run, we can actually miss any
1911 breakpoint, not just the one at PC. */
1912 resume_ptid
= inferior_ptid
;
1915 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1917 /* Most targets can step a breakpoint instruction, thus
1918 executing it normally. But if this one cannot, just
1919 continue and we will hit it anyway. */
1920 if (step
&& breakpoint_inserted_here_p (aspace
, pc
))
1925 && use_displaced_stepping (gdbarch
)
1926 && tp
->control
.trap_expected
)
1928 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1929 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
1930 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1933 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1934 paddress (resume_gdbarch
, actual_pc
));
1935 read_memory (actual_pc
, buf
, sizeof (buf
));
1936 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1939 /* Install inferior's terminal modes. */
1940 target_terminal_inferior ();
1942 /* Avoid confusing the next resume, if the next stop/resume
1943 happens to apply to another thread. */
1944 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1946 /* Advise target which signals may be handled silently. If we have
1947 removed breakpoints because we are stepping over one (which can
1948 happen only if we are not using displaced stepping), we need to
1949 receive all signals to avoid accidentally skipping a breakpoint
1950 during execution of a signal handler. */
1951 if ((step
|| singlestep_breakpoints_inserted_p
)
1952 && tp
->control
.trap_expected
1953 && !use_displaced_stepping (gdbarch
))
1954 target_pass_signals (0, NULL
);
1956 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
1958 target_resume (resume_ptid
, step
, sig
);
1961 discard_cleanups (old_cleanups
);
1966 /* Clear out all variables saying what to do when inferior is continued.
1967 First do this, then set the ones you want, then call `proceed'. */
1970 clear_proceed_status_thread (struct thread_info
*tp
)
1973 fprintf_unfiltered (gdb_stdlog
,
1974 "infrun: clear_proceed_status_thread (%s)\n",
1975 target_pid_to_str (tp
->ptid
));
1977 tp
->control
.trap_expected
= 0;
1978 tp
->control
.step_range_start
= 0;
1979 tp
->control
.step_range_end
= 0;
1980 tp
->control
.step_frame_id
= null_frame_id
;
1981 tp
->control
.step_stack_frame_id
= null_frame_id
;
1982 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1983 tp
->stop_requested
= 0;
1985 tp
->control
.stop_step
= 0;
1987 tp
->control
.proceed_to_finish
= 0;
1989 /* Discard any remaining commands or status from previous stop. */
1990 bpstat_clear (&tp
->control
.stop_bpstat
);
1994 clear_proceed_status_callback (struct thread_info
*tp
, void *data
)
1996 if (is_exited (tp
->ptid
))
1999 clear_proceed_status_thread (tp
);
2004 clear_proceed_status (void)
2008 /* In all-stop mode, delete the per-thread status of all
2009 threads, even if inferior_ptid is null_ptid, there may be
2010 threads on the list. E.g., we may be launching a new
2011 process, while selecting the executable. */
2012 iterate_over_threads (clear_proceed_status_callback
, NULL
);
2015 if (!ptid_equal (inferior_ptid
, null_ptid
))
2017 struct inferior
*inferior
;
2021 /* If in non-stop mode, only delete the per-thread status of
2022 the current thread. */
2023 clear_proceed_status_thread (inferior_thread ());
2026 inferior
= current_inferior ();
2027 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2030 stop_after_trap
= 0;
2032 observer_notify_about_to_proceed ();
2036 regcache_xfree (stop_registers
);
2037 stop_registers
= NULL
;
2041 /* Check the current thread against the thread that reported the most recent
2042 event. If a step-over is required return TRUE and set the current thread
2043 to the old thread. Otherwise return FALSE.
2045 This should be suitable for any targets that support threads. */
2048 prepare_to_proceed (int step
)
2051 struct target_waitstatus wait_status
;
2052 int schedlock_enabled
;
2054 /* With non-stop mode on, threads are always handled individually. */
2055 gdb_assert (! non_stop
);
2057 /* Get the last target status returned by target_wait(). */
2058 get_last_target_status (&wait_ptid
, &wait_status
);
2060 /* Make sure we were stopped at a breakpoint. */
2061 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
2062 || (wait_status
.value
.sig
!= GDB_SIGNAL_TRAP
2063 && wait_status
.value
.sig
!= GDB_SIGNAL_ILL
2064 && wait_status
.value
.sig
!= GDB_SIGNAL_SEGV
2065 && wait_status
.value
.sig
!= GDB_SIGNAL_EMT
))
2070 schedlock_enabled
= (scheduler_mode
== schedlock_on
2071 || (scheduler_mode
== schedlock_step
2074 /* Don't switch over to WAIT_PTID if scheduler locking is on. */
2075 if (schedlock_enabled
)
2078 /* Don't switch over if we're about to resume some other process
2079 other than WAIT_PTID's, and schedule-multiple is off. */
2081 && ptid_get_pid (wait_ptid
) != ptid_get_pid (inferior_ptid
))
2084 /* Switched over from WAIT_PID. */
2085 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
2086 && !ptid_equal (inferior_ptid
, wait_ptid
))
2088 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
2090 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2091 regcache_read_pc (regcache
)))
2093 /* If stepping, remember current thread to switch back to. */
2095 deferred_step_ptid
= inferior_ptid
;
2097 /* Switch back to WAIT_PID thread. */
2098 switch_to_thread (wait_ptid
);
2101 fprintf_unfiltered (gdb_stdlog
,
2102 "infrun: prepare_to_proceed (step=%d), "
2103 "switched to [%s]\n",
2104 step
, target_pid_to_str (inferior_ptid
));
2106 /* We return 1 to indicate that there is a breakpoint here,
2107 so we need to step over it before continuing to avoid
2108 hitting it straight away. */
2116 /* Basic routine for continuing the program in various fashions.
2118 ADDR is the address to resume at, or -1 for resume where stopped.
2119 SIGGNAL is the signal to give it, or 0 for none,
2120 or -1 for act according to how it stopped.
2121 STEP is nonzero if should trap after one instruction.
2122 -1 means return after that and print nothing.
2123 You should probably set various step_... variables
2124 before calling here, if you are stepping.
2126 You should call clear_proceed_status before calling proceed. */
2129 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
, int step
)
2131 struct regcache
*regcache
;
2132 struct gdbarch
*gdbarch
;
2133 struct thread_info
*tp
;
2135 struct address_space
*aspace
;
2138 /* If we're stopped at a fork/vfork, follow the branch set by the
2139 "set follow-fork-mode" command; otherwise, we'll just proceed
2140 resuming the current thread. */
2141 if (!follow_fork ())
2143 /* The target for some reason decided not to resume. */
2145 if (target_can_async_p ())
2146 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2150 /* We'll update this if & when we switch to a new thread. */
2151 previous_inferior_ptid
= inferior_ptid
;
2153 regcache
= get_current_regcache ();
2154 gdbarch
= get_regcache_arch (regcache
);
2155 aspace
= get_regcache_aspace (regcache
);
2156 pc
= regcache_read_pc (regcache
);
2159 step_start_function
= find_pc_function (pc
);
2161 stop_after_trap
= 1;
2163 if (addr
== (CORE_ADDR
) -1)
2165 if (pc
== stop_pc
&& breakpoint_here_p (aspace
, pc
)
2166 && execution_direction
!= EXEC_REVERSE
)
2167 /* There is a breakpoint at the address we will resume at,
2168 step one instruction before inserting breakpoints so that
2169 we do not stop right away (and report a second hit at this
2172 Note, we don't do this in reverse, because we won't
2173 actually be executing the breakpoint insn anyway.
2174 We'll be (un-)executing the previous instruction. */
2177 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2178 && gdbarch_single_step_through_delay (gdbarch
,
2179 get_current_frame ()))
2180 /* We stepped onto an instruction that needs to be stepped
2181 again before re-inserting the breakpoint, do so. */
2186 regcache_write_pc (regcache
, addr
);
2190 fprintf_unfiltered (gdb_stdlog
,
2191 "infrun: proceed (addr=%s, signal=%d, step=%d)\n",
2192 paddress (gdbarch
, addr
), siggnal
, step
);
2195 /* In non-stop, each thread is handled individually. The context
2196 must already be set to the right thread here. */
2200 /* In a multi-threaded task we may select another thread and
2201 then continue or step.
2203 But if the old thread was stopped at a breakpoint, it will
2204 immediately cause another breakpoint stop without any
2205 execution (i.e. it will report a breakpoint hit incorrectly).
2206 So we must step over it first.
2208 prepare_to_proceed checks the current thread against the
2209 thread that reported the most recent event. If a step-over
2210 is required it returns TRUE and sets the current thread to
2212 if (prepare_to_proceed (step
))
2216 /* prepare_to_proceed may change the current thread. */
2217 tp
= inferior_thread ();
2221 tp
->control
.trap_expected
= 1;
2222 /* If displaced stepping is enabled, we can step over the
2223 breakpoint without hitting it, so leave all breakpoints
2224 inserted. Otherwise we need to disable all breakpoints, step
2225 one instruction, and then re-add them when that step is
2227 if (!use_displaced_stepping (gdbarch
))
2228 remove_breakpoints ();
2231 /* We can insert breakpoints if we're not trying to step over one,
2232 or if we are stepping over one but we're using displaced stepping
2234 if (! tp
->control
.trap_expected
|| use_displaced_stepping (gdbarch
))
2235 insert_breakpoints ();
2239 /* Pass the last stop signal to the thread we're resuming,
2240 irrespective of whether the current thread is the thread that
2241 got the last event or not. This was historically GDB's
2242 behaviour before keeping a stop_signal per thread. */
2244 struct thread_info
*last_thread
;
2246 struct target_waitstatus last_status
;
2248 get_last_target_status (&last_ptid
, &last_status
);
2249 if (!ptid_equal (inferior_ptid
, last_ptid
)
2250 && !ptid_equal (last_ptid
, null_ptid
)
2251 && !ptid_equal (last_ptid
, minus_one_ptid
))
2253 last_thread
= find_thread_ptid (last_ptid
);
2256 tp
->suspend
.stop_signal
= last_thread
->suspend
.stop_signal
;
2257 last_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2262 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2263 tp
->suspend
.stop_signal
= siggnal
;
2264 /* If this signal should not be seen by program,
2265 give it zero. Used for debugging signals. */
2266 else if (!signal_program
[tp
->suspend
.stop_signal
])
2267 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2269 annotate_starting ();
2271 /* Make sure that output from GDB appears before output from the
2273 gdb_flush (gdb_stdout
);
2275 /* Refresh prev_pc value just prior to resuming. This used to be
2276 done in stop_stepping, however, setting prev_pc there did not handle
2277 scenarios such as inferior function calls or returning from
2278 a function via the return command. In those cases, the prev_pc
2279 value was not set properly for subsequent commands. The prev_pc value
2280 is used to initialize the starting line number in the ecs. With an
2281 invalid value, the gdb next command ends up stopping at the position
2282 represented by the next line table entry past our start position.
2283 On platforms that generate one line table entry per line, this
2284 is not a problem. However, on the ia64, the compiler generates
2285 extraneous line table entries that do not increase the line number.
2286 When we issue the gdb next command on the ia64 after an inferior call
2287 or a return command, we often end up a few instructions forward, still
2288 within the original line we started.
2290 An attempt was made to refresh the prev_pc at the same time the
2291 execution_control_state is initialized (for instance, just before
2292 waiting for an inferior event). But this approach did not work
2293 because of platforms that use ptrace, where the pc register cannot
2294 be read unless the inferior is stopped. At that point, we are not
2295 guaranteed the inferior is stopped and so the regcache_read_pc() call
2296 can fail. Setting the prev_pc value here ensures the value is updated
2297 correctly when the inferior is stopped. */
2298 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2300 /* Fill in with reasonable starting values. */
2301 init_thread_stepping_state (tp
);
2303 /* Reset to normal state. */
2304 init_infwait_state ();
2306 /* Resume inferior. */
2307 resume (oneproc
|| step
|| bpstat_should_step (), tp
->suspend
.stop_signal
);
2309 /* Wait for it to stop (if not standalone)
2310 and in any case decode why it stopped, and act accordingly. */
2311 /* Do this only if we are not using the event loop, or if the target
2312 does not support asynchronous execution. */
2313 if (!target_can_async_p ())
2315 wait_for_inferior ();
2321 /* Start remote-debugging of a machine over a serial link. */
2324 start_remote (int from_tty
)
2326 struct inferior
*inferior
;
2328 inferior
= current_inferior ();
2329 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
2331 /* Always go on waiting for the target, regardless of the mode. */
2332 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2333 indicate to wait_for_inferior that a target should timeout if
2334 nothing is returned (instead of just blocking). Because of this,
2335 targets expecting an immediate response need to, internally, set
2336 things up so that the target_wait() is forced to eventually
2338 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2339 differentiate to its caller what the state of the target is after
2340 the initial open has been performed. Here we're assuming that
2341 the target has stopped. It should be possible to eventually have
2342 target_open() return to the caller an indication that the target
2343 is currently running and GDB state should be set to the same as
2344 for an async run. */
2345 wait_for_inferior ();
2347 /* Now that the inferior has stopped, do any bookkeeping like
2348 loading shared libraries. We want to do this before normal_stop,
2349 so that the displayed frame is up to date. */
2350 post_create_inferior (¤t_target
, from_tty
);
2355 /* Initialize static vars when a new inferior begins. */
2358 init_wait_for_inferior (void)
2360 /* These are meaningless until the first time through wait_for_inferior. */
2362 breakpoint_init_inferior (inf_starting
);
2364 clear_proceed_status ();
2366 stepping_past_singlestep_breakpoint
= 0;
2367 deferred_step_ptid
= null_ptid
;
2369 target_last_wait_ptid
= minus_one_ptid
;
2371 previous_inferior_ptid
= inferior_ptid
;
2372 init_infwait_state ();
2374 /* Discard any skipped inlined frames. */
2375 clear_inline_frame_state (minus_one_ptid
);
2379 /* This enum encodes possible reasons for doing a target_wait, so that
2380 wfi can call target_wait in one place. (Ultimately the call will be
2381 moved out of the infinite loop entirely.) */
2385 infwait_normal_state
,
2386 infwait_thread_hop_state
,
2387 infwait_step_watch_state
,
2388 infwait_nonstep_watch_state
2391 /* The PTID we'll do a target_wait on.*/
2394 /* Current inferior wait state. */
2395 static enum infwait_states infwait_state
;
2397 /* Data to be passed around while handling an event. This data is
2398 discarded between events. */
2399 struct execution_control_state
2402 /* The thread that got the event, if this was a thread event; NULL
2404 struct thread_info
*event_thread
;
2406 struct target_waitstatus ws
;
2408 int stop_func_filled_in
;
2409 CORE_ADDR stop_func_start
;
2410 CORE_ADDR stop_func_end
;
2411 const char *stop_func_name
;
2415 static void handle_inferior_event (struct execution_control_state
*ecs
);
2417 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2418 struct execution_control_state
*ecs
);
2419 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2420 struct execution_control_state
*ecs
);
2421 static void check_exception_resume (struct execution_control_state
*,
2422 struct frame_info
*);
2424 static void stop_stepping (struct execution_control_state
*ecs
);
2425 static void prepare_to_wait (struct execution_control_state
*ecs
);
2426 static void keep_going (struct execution_control_state
*ecs
);
2428 /* Callback for iterate over threads. If the thread is stopped, but
2429 the user/frontend doesn't know about that yet, go through
2430 normal_stop, as if the thread had just stopped now. ARG points at
2431 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2432 ptid_is_pid(PTID) is true, applies to all threads of the process
2433 pointed at by PTID. Otherwise, apply only to the thread pointed by
2437 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2439 ptid_t ptid
= * (ptid_t
*) arg
;
2441 if ((ptid_equal (info
->ptid
, ptid
)
2442 || ptid_equal (minus_one_ptid
, ptid
)
2443 || (ptid_is_pid (ptid
)
2444 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2445 && is_running (info
->ptid
)
2446 && !is_executing (info
->ptid
))
2448 struct cleanup
*old_chain
;
2449 struct execution_control_state ecss
;
2450 struct execution_control_state
*ecs
= &ecss
;
2452 memset (ecs
, 0, sizeof (*ecs
));
2454 old_chain
= make_cleanup_restore_current_thread ();
2456 /* Go through handle_inferior_event/normal_stop, so we always
2457 have consistent output as if the stop event had been
2459 ecs
->ptid
= info
->ptid
;
2460 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2461 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2462 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
2464 handle_inferior_event (ecs
);
2466 if (!ecs
->wait_some_more
)
2468 struct thread_info
*tp
;
2472 /* Finish off the continuations. */
2473 tp
= inferior_thread ();
2474 do_all_intermediate_continuations_thread (tp
, 1);
2475 do_all_continuations_thread (tp
, 1);
2478 do_cleanups (old_chain
);
2484 /* This function is attached as a "thread_stop_requested" observer.
2485 Cleanup local state that assumed the PTID was to be resumed, and
2486 report the stop to the frontend. */
2489 infrun_thread_stop_requested (ptid_t ptid
)
2491 struct displaced_step_inferior_state
*displaced
;
2493 /* PTID was requested to stop. Remove it from the displaced
2494 stepping queue, so we don't try to resume it automatically. */
2496 for (displaced
= displaced_step_inferior_states
;
2498 displaced
= displaced
->next
)
2500 struct displaced_step_request
*it
, **prev_next_p
;
2502 it
= displaced
->step_request_queue
;
2503 prev_next_p
= &displaced
->step_request_queue
;
2506 if (ptid_match (it
->ptid
, ptid
))
2508 *prev_next_p
= it
->next
;
2514 prev_next_p
= &it
->next
;
2521 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2525 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2527 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2528 nullify_last_target_wait_ptid ();
2531 /* Callback for iterate_over_threads. */
2534 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
2536 if (is_exited (info
->ptid
))
2539 delete_step_resume_breakpoint (info
);
2540 delete_exception_resume_breakpoint (info
);
2544 /* In all-stop, delete the step resume breakpoint of any thread that
2545 had one. In non-stop, delete the step resume breakpoint of the
2546 thread that just stopped. */
2549 delete_step_thread_step_resume_breakpoint (void)
2551 if (!target_has_execution
2552 || ptid_equal (inferior_ptid
, null_ptid
))
2553 /* If the inferior has exited, we have already deleted the step
2554 resume breakpoints out of GDB's lists. */
2559 /* If in non-stop mode, only delete the step-resume or
2560 longjmp-resume breakpoint of the thread that just stopped
2562 struct thread_info
*tp
= inferior_thread ();
2564 delete_step_resume_breakpoint (tp
);
2565 delete_exception_resume_breakpoint (tp
);
2568 /* In all-stop mode, delete all step-resume and longjmp-resume
2569 breakpoints of any thread that had them. */
2570 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
2573 /* A cleanup wrapper. */
2576 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
2578 delete_step_thread_step_resume_breakpoint ();
2581 /* Pretty print the results of target_wait, for debugging purposes. */
2584 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
2585 const struct target_waitstatus
*ws
)
2587 char *status_string
= target_waitstatus_to_string (ws
);
2588 struct ui_file
*tmp_stream
= mem_fileopen ();
2591 /* The text is split over several lines because it was getting too long.
2592 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2593 output as a unit; we want only one timestamp printed if debug_timestamp
2596 fprintf_unfiltered (tmp_stream
,
2597 "infrun: target_wait (%d", PIDGET (waiton_ptid
));
2598 if (PIDGET (waiton_ptid
) != -1)
2599 fprintf_unfiltered (tmp_stream
,
2600 " [%s]", target_pid_to_str (waiton_ptid
));
2601 fprintf_unfiltered (tmp_stream
, ", status) =\n");
2602 fprintf_unfiltered (tmp_stream
,
2603 "infrun: %d [%s],\n",
2604 PIDGET (result_ptid
), target_pid_to_str (result_ptid
));
2605 fprintf_unfiltered (tmp_stream
,
2609 text
= ui_file_xstrdup (tmp_stream
, NULL
);
2611 /* This uses %s in part to handle %'s in the text, but also to avoid
2612 a gcc error: the format attribute requires a string literal. */
2613 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
2615 xfree (status_string
);
2617 ui_file_delete (tmp_stream
);
2620 /* Prepare and stabilize the inferior for detaching it. E.g.,
2621 detaching while a thread is displaced stepping is a recipe for
2622 crashing it, as nothing would readjust the PC out of the scratch
2626 prepare_for_detach (void)
2628 struct inferior
*inf
= current_inferior ();
2629 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
2630 struct cleanup
*old_chain_1
;
2631 struct displaced_step_inferior_state
*displaced
;
2633 displaced
= get_displaced_stepping_state (inf
->pid
);
2635 /* Is any thread of this process displaced stepping? If not,
2636 there's nothing else to do. */
2637 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
2641 fprintf_unfiltered (gdb_stdlog
,
2642 "displaced-stepping in-process while detaching");
2644 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
2647 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
2649 struct cleanup
*old_chain_2
;
2650 struct execution_control_state ecss
;
2651 struct execution_control_state
*ecs
;
2654 memset (ecs
, 0, sizeof (*ecs
));
2656 overlay_cache_invalid
= 1;
2658 if (deprecated_target_wait_hook
)
2659 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
2661 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
2664 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
2666 /* If an error happens while handling the event, propagate GDB's
2667 knowledge of the executing state to the frontend/user running
2669 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
2672 /* Now figure out what to do with the result of the result. */
2673 handle_inferior_event (ecs
);
2675 /* No error, don't finish the state yet. */
2676 discard_cleanups (old_chain_2
);
2678 /* Breakpoints and watchpoints are not installed on the target
2679 at this point, and signals are passed directly to the
2680 inferior, so this must mean the process is gone. */
2681 if (!ecs
->wait_some_more
)
2683 discard_cleanups (old_chain_1
);
2684 error (_("Program exited while detaching"));
2688 discard_cleanups (old_chain_1
);
2691 /* Wait for control to return from inferior to debugger.
2693 If inferior gets a signal, we may decide to start it up again
2694 instead of returning. That is why there is a loop in this function.
2695 When this function actually returns it means the inferior
2696 should be left stopped and GDB should read more commands. */
2699 wait_for_inferior (void)
2701 struct cleanup
*old_cleanups
;
2705 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
2708 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
2712 struct execution_control_state ecss
;
2713 struct execution_control_state
*ecs
= &ecss
;
2714 struct cleanup
*old_chain
;
2716 memset (ecs
, 0, sizeof (*ecs
));
2718 overlay_cache_invalid
= 1;
2720 if (deprecated_target_wait_hook
)
2721 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
2723 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
2726 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2728 /* If an error happens while handling the event, propagate GDB's
2729 knowledge of the executing state to the frontend/user running
2731 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2733 /* Now figure out what to do with the result of the result. */
2734 handle_inferior_event (ecs
);
2736 /* No error, don't finish the state yet. */
2737 discard_cleanups (old_chain
);
2739 if (!ecs
->wait_some_more
)
2743 do_cleanups (old_cleanups
);
2746 /* Asynchronous version of wait_for_inferior. It is called by the
2747 event loop whenever a change of state is detected on the file
2748 descriptor corresponding to the target. It can be called more than
2749 once to complete a single execution command. In such cases we need
2750 to keep the state in a global variable ECSS. If it is the last time
2751 that this function is called for a single execution command, then
2752 report to the user that the inferior has stopped, and do the
2753 necessary cleanups. */
2756 fetch_inferior_event (void *client_data
)
2758 struct execution_control_state ecss
;
2759 struct execution_control_state
*ecs
= &ecss
;
2760 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
2761 struct cleanup
*ts_old_chain
;
2762 int was_sync
= sync_execution
;
2765 memset (ecs
, 0, sizeof (*ecs
));
2767 /* We're handling a live event, so make sure we're doing live
2768 debugging. If we're looking at traceframes while the target is
2769 running, we're going to need to get back to that mode after
2770 handling the event. */
2773 make_cleanup_restore_current_traceframe ();
2774 set_current_traceframe (-1);
2778 /* In non-stop mode, the user/frontend should not notice a thread
2779 switch due to internal events. Make sure we reverse to the
2780 user selected thread and frame after handling the event and
2781 running any breakpoint commands. */
2782 make_cleanup_restore_current_thread ();
2784 overlay_cache_invalid
= 1;
2786 make_cleanup_restore_integer (&execution_direction
);
2787 execution_direction
= target_execution_direction ();
2789 if (deprecated_target_wait_hook
)
2791 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2793 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2796 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2798 /* If an error happens while handling the event, propagate GDB's
2799 knowledge of the executing state to the frontend/user running
2802 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2804 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
2806 /* Get executed before make_cleanup_restore_current_thread above to apply
2807 still for the thread which has thrown the exception. */
2808 make_bpstat_clear_actions_cleanup ();
2810 /* Now figure out what to do with the result of the result. */
2811 handle_inferior_event (ecs
);
2813 if (!ecs
->wait_some_more
)
2815 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2817 delete_step_thread_step_resume_breakpoint ();
2819 /* We may not find an inferior if this was a process exit. */
2820 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
2823 if (target_has_execution
2824 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
2825 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2826 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2827 && ecs
->event_thread
->step_multi
2828 && ecs
->event_thread
->control
.stop_step
)
2829 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
2832 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2837 /* No error, don't finish the thread states yet. */
2838 discard_cleanups (ts_old_chain
);
2840 /* Revert thread and frame. */
2841 do_cleanups (old_chain
);
2843 /* If the inferior was in sync execution mode, and now isn't,
2844 restore the prompt (a synchronous execution command has finished,
2845 and we're ready for input). */
2846 if (interpreter_async
&& was_sync
&& !sync_execution
)
2847 display_gdb_prompt (0);
2851 && exec_done_display_p
2852 && (ptid_equal (inferior_ptid
, null_ptid
)
2853 || !is_running (inferior_ptid
)))
2854 printf_unfiltered (_("completed.\n"));
2857 /* Record the frame and location we're currently stepping through. */
2859 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
2861 struct thread_info
*tp
= inferior_thread ();
2863 tp
->control
.step_frame_id
= get_frame_id (frame
);
2864 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
2866 tp
->current_symtab
= sal
.symtab
;
2867 tp
->current_line
= sal
.line
;
2870 /* Clear context switchable stepping state. */
2873 init_thread_stepping_state (struct thread_info
*tss
)
2875 tss
->stepping_over_breakpoint
= 0;
2876 tss
->step_after_step_resume_breakpoint
= 0;
2879 /* Return the cached copy of the last pid/waitstatus returned by
2880 target_wait()/deprecated_target_wait_hook(). The data is actually
2881 cached by handle_inferior_event(), which gets called immediately
2882 after target_wait()/deprecated_target_wait_hook(). */
2885 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
2887 *ptidp
= target_last_wait_ptid
;
2888 *status
= target_last_waitstatus
;
2892 nullify_last_target_wait_ptid (void)
2894 target_last_wait_ptid
= minus_one_ptid
;
2897 /* Switch thread contexts. */
2900 context_switch (ptid_t ptid
)
2902 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
2904 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
2905 target_pid_to_str (inferior_ptid
));
2906 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
2907 target_pid_to_str (ptid
));
2910 switch_to_thread (ptid
);
2914 adjust_pc_after_break (struct execution_control_state
*ecs
)
2916 struct regcache
*regcache
;
2917 struct gdbarch
*gdbarch
;
2918 struct address_space
*aspace
;
2919 CORE_ADDR breakpoint_pc
;
2921 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2922 we aren't, just return.
2924 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2925 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2926 implemented by software breakpoints should be handled through the normal
2929 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2930 different signals (SIGILL or SIGEMT for instance), but it is less
2931 clear where the PC is pointing afterwards. It may not match
2932 gdbarch_decr_pc_after_break. I don't know any specific target that
2933 generates these signals at breakpoints (the code has been in GDB since at
2934 least 1992) so I can not guess how to handle them here.
2936 In earlier versions of GDB, a target with
2937 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2938 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2939 target with both of these set in GDB history, and it seems unlikely to be
2940 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2942 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
2945 if (ecs
->ws
.value
.sig
!= GDB_SIGNAL_TRAP
)
2948 /* In reverse execution, when a breakpoint is hit, the instruction
2949 under it has already been de-executed. The reported PC always
2950 points at the breakpoint address, so adjusting it further would
2951 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2954 B1 0x08000000 : INSN1
2955 B2 0x08000001 : INSN2
2957 PC -> 0x08000003 : INSN4
2959 Say you're stopped at 0x08000003 as above. Reverse continuing
2960 from that point should hit B2 as below. Reading the PC when the
2961 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2962 been de-executed already.
2964 B1 0x08000000 : INSN1
2965 B2 PC -> 0x08000001 : INSN2
2969 We can't apply the same logic as for forward execution, because
2970 we would wrongly adjust the PC to 0x08000000, since there's a
2971 breakpoint at PC - 1. We'd then report a hit on B1, although
2972 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2974 if (execution_direction
== EXEC_REVERSE
)
2977 /* If this target does not decrement the PC after breakpoints, then
2978 we have nothing to do. */
2979 regcache
= get_thread_regcache (ecs
->ptid
);
2980 gdbarch
= get_regcache_arch (regcache
);
2981 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
2984 aspace
= get_regcache_aspace (regcache
);
2986 /* Find the location where (if we've hit a breakpoint) the
2987 breakpoint would be. */
2988 breakpoint_pc
= regcache_read_pc (regcache
)
2989 - gdbarch_decr_pc_after_break (gdbarch
);
2991 /* Check whether there actually is a software breakpoint inserted at
2994 If in non-stop mode, a race condition is possible where we've
2995 removed a breakpoint, but stop events for that breakpoint were
2996 already queued and arrive later. To suppress those spurious
2997 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
2998 and retire them after a number of stop events are reported. */
2999 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3000 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3002 struct cleanup
*old_cleanups
= NULL
;
3005 old_cleanups
= record_gdb_operation_disable_set ();
3007 /* When using hardware single-step, a SIGTRAP is reported for both
3008 a completed single-step and a software breakpoint. Need to
3009 differentiate between the two, as the latter needs adjusting
3010 but the former does not.
3012 The SIGTRAP can be due to a completed hardware single-step only if
3013 - we didn't insert software single-step breakpoints
3014 - the thread to be examined is still the current thread
3015 - this thread is currently being stepped
3017 If any of these events did not occur, we must have stopped due
3018 to hitting a software breakpoint, and have to back up to the
3021 As a special case, we could have hardware single-stepped a
3022 software breakpoint. In this case (prev_pc == breakpoint_pc),
3023 we also need to back up to the breakpoint address. */
3025 if (singlestep_breakpoints_inserted_p
3026 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
3027 || !currently_stepping (ecs
->event_thread
)
3028 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
3029 regcache_write_pc (regcache
, breakpoint_pc
);
3032 do_cleanups (old_cleanups
);
3037 init_infwait_state (void)
3039 waiton_ptid
= pid_to_ptid (-1);
3040 infwait_state
= infwait_normal_state
;
3044 error_is_running (void)
3046 error (_("Cannot execute this command while "
3047 "the selected thread is running."));
3051 ensure_not_running (void)
3053 if (is_running (inferior_ptid
))
3054 error_is_running ();
3058 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3060 for (frame
= get_prev_frame (frame
);
3062 frame
= get_prev_frame (frame
))
3064 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3066 if (get_frame_type (frame
) != INLINE_FRAME
)
3073 /* Auxiliary function that handles syscall entry/return events.
3074 It returns 1 if the inferior should keep going (and GDB
3075 should ignore the event), or 0 if the event deserves to be
3079 handle_syscall_event (struct execution_control_state
*ecs
)
3081 struct regcache
*regcache
;
3082 struct gdbarch
*gdbarch
;
3085 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3086 context_switch (ecs
->ptid
);
3088 regcache
= get_thread_regcache (ecs
->ptid
);
3089 gdbarch
= get_regcache_arch (regcache
);
3090 syscall_number
= ecs
->ws
.value
.syscall_number
;
3091 stop_pc
= regcache_read_pc (regcache
);
3093 if (catch_syscall_enabled () > 0
3094 && catching_syscall_number (syscall_number
) > 0)
3097 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3100 ecs
->event_thread
->control
.stop_bpstat
3101 = bpstat_stop_status (get_regcache_aspace (regcache
),
3102 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3104 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3106 if (!ecs
->random_signal
)
3108 /* Catchpoint hit. */
3109 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3114 /* If no catchpoint triggered for this, then keep going. */
3115 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3120 /* Clear the supplied execution_control_state's stop_func_* fields. */
3123 clear_stop_func (struct execution_control_state
*ecs
)
3125 ecs
->stop_func_filled_in
= 0;
3126 ecs
->stop_func_start
= 0;
3127 ecs
->stop_func_end
= 0;
3128 ecs
->stop_func_name
= NULL
;
3131 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3134 fill_in_stop_func (struct gdbarch
*gdbarch
,
3135 struct execution_control_state
*ecs
)
3137 if (!ecs
->stop_func_filled_in
)
3139 /* Don't care about return value; stop_func_start and stop_func_name
3140 will both be 0 if it doesn't work. */
3141 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3142 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3143 ecs
->stop_func_start
3144 += gdbarch_deprecated_function_start_offset (gdbarch
);
3146 ecs
->stop_func_filled_in
= 1;
3150 /* Given an execution control state that has been freshly filled in
3151 by an event from the inferior, figure out what it means and take
3152 appropriate action. */
3155 handle_inferior_event (struct execution_control_state
*ecs
)
3157 struct frame_info
*frame
;
3158 struct gdbarch
*gdbarch
;
3159 int stopped_by_watchpoint
;
3160 int stepped_after_stopped_by_watchpoint
= 0;
3161 struct symtab_and_line stop_pc_sal
;
3162 enum stop_kind stop_soon
;
3164 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3166 /* We had an event in the inferior, but we are not interested in
3167 handling it at this level. The lower layers have already
3168 done what needs to be done, if anything.
3170 One of the possible circumstances for this is when the
3171 inferior produces output for the console. The inferior has
3172 not stopped, and we are ignoring the event. Another possible
3173 circumstance is any event which the lower level knows will be
3174 reported multiple times without an intervening resume. */
3176 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3177 prepare_to_wait (ecs
);
3181 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3182 && target_can_async_p () && !sync_execution
)
3184 /* There were no unwaited-for children left in the target, but,
3185 we're not synchronously waiting for events either. Just
3186 ignore. Otherwise, if we were running a synchronous
3187 execution command, we need to cancel it and give the user
3188 back the terminal. */
3190 fprintf_unfiltered (gdb_stdlog
,
3191 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3192 prepare_to_wait (ecs
);
3196 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3197 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3198 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
3200 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3203 stop_soon
= inf
->control
.stop_soon
;
3206 stop_soon
= NO_STOP_QUIETLY
;
3208 /* Cache the last pid/waitstatus. */
3209 target_last_wait_ptid
= ecs
->ptid
;
3210 target_last_waitstatus
= ecs
->ws
;
3212 /* Always clear state belonging to the previous time we stopped. */
3213 stop_stack_dummy
= STOP_NONE
;
3215 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3217 /* No unwaited-for children left. IOW, all resumed children
3220 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3222 stop_print_frame
= 0;
3223 stop_stepping (ecs
);
3227 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3228 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
3230 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3231 /* If it's a new thread, add it to the thread database. */
3232 if (ecs
->event_thread
== NULL
)
3233 ecs
->event_thread
= add_thread (ecs
->ptid
);
3236 /* Dependent on valid ECS->EVENT_THREAD. */
3237 adjust_pc_after_break (ecs
);
3239 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3240 reinit_frame_cache ();
3242 breakpoint_retire_moribund ();
3244 /* First, distinguish signals caused by the debugger from signals
3245 that have to do with the program's own actions. Note that
3246 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3247 on the operating system version. Here we detect when a SIGILL or
3248 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3249 something similar for SIGSEGV, since a SIGSEGV will be generated
3250 when we're trying to execute a breakpoint instruction on a
3251 non-executable stack. This happens for call dummy breakpoints
3252 for architectures like SPARC that place call dummies on the
3254 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3255 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3256 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3257 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3259 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3261 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3262 regcache_read_pc (regcache
)))
3265 fprintf_unfiltered (gdb_stdlog
,
3266 "infrun: Treating signal as SIGTRAP\n");
3267 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3271 /* Mark the non-executing threads accordingly. In all-stop, all
3272 threads of all processes are stopped when we get any event
3273 reported. In non-stop mode, only the event thread stops. If
3274 we're handling a process exit in non-stop mode, there's nothing
3275 to do, as threads of the dead process are gone, and threads of
3276 any other process were left running. */
3278 set_executing (minus_one_ptid
, 0);
3279 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3280 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3281 set_executing (ecs
->ptid
, 0);
3283 switch (infwait_state
)
3285 case infwait_thread_hop_state
:
3287 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
3290 case infwait_normal_state
:
3292 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
3295 case infwait_step_watch_state
:
3297 fprintf_unfiltered (gdb_stdlog
,
3298 "infrun: infwait_step_watch_state\n");
3300 stepped_after_stopped_by_watchpoint
= 1;
3303 case infwait_nonstep_watch_state
:
3305 fprintf_unfiltered (gdb_stdlog
,
3306 "infrun: infwait_nonstep_watch_state\n");
3307 insert_breakpoints ();
3309 /* FIXME-maybe: is this cleaner than setting a flag? Does it
3310 handle things like signals arriving and other things happening
3311 in combination correctly? */
3312 stepped_after_stopped_by_watchpoint
= 1;
3316 internal_error (__FILE__
, __LINE__
, _("bad switch"));
3319 infwait_state
= infwait_normal_state
;
3320 waiton_ptid
= pid_to_ptid (-1);
3322 switch (ecs
->ws
.kind
)
3324 case TARGET_WAITKIND_LOADED
:
3326 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3327 /* Ignore gracefully during startup of the inferior, as it might
3328 be the shell which has just loaded some objects, otherwise
3329 add the symbols for the newly loaded objects. Also ignore at
3330 the beginning of an attach or remote session; we will query
3331 the full list of libraries once the connection is
3333 if (stop_soon
== NO_STOP_QUIETLY
)
3335 struct regcache
*regcache
;
3337 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3338 context_switch (ecs
->ptid
);
3339 regcache
= get_thread_regcache (ecs
->ptid
);
3341 handle_solib_event ();
3343 ecs
->event_thread
->control
.stop_bpstat
3344 = bpstat_stop_status (get_regcache_aspace (regcache
),
3345 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3347 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3349 if (!ecs
->random_signal
)
3351 /* A catchpoint triggered. */
3352 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3353 goto process_event_stop_test
;
3356 /* If requested, stop when the dynamic linker notifies
3357 gdb of events. This allows the user to get control
3358 and place breakpoints in initializer routines for
3359 dynamically loaded objects (among other things). */
3360 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3361 if (stop_on_solib_events
)
3363 /* Make sure we print "Stopped due to solib-event" in
3365 stop_print_frame
= 1;
3367 stop_stepping (ecs
);
3372 /* If we are skipping through a shell, or through shared library
3373 loading that we aren't interested in, resume the program. If
3374 we're running the program normally, also resume. But stop if
3375 we're attaching or setting up a remote connection. */
3376 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3378 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3379 context_switch (ecs
->ptid
);
3381 /* Loading of shared libraries might have changed breakpoint
3382 addresses. Make sure new breakpoints are inserted. */
3383 if (stop_soon
== NO_STOP_QUIETLY
3384 && !breakpoints_always_inserted_mode ())
3385 insert_breakpoints ();
3386 resume (0, GDB_SIGNAL_0
);
3387 prepare_to_wait (ecs
);
3393 case TARGET_WAITKIND_SPURIOUS
:
3395 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3396 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3397 context_switch (ecs
->ptid
);
3398 resume (0, GDB_SIGNAL_0
);
3399 prepare_to_wait (ecs
);
3402 case TARGET_WAITKIND_EXITED
:
3403 case TARGET_WAITKIND_SIGNALLED
:
3406 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3407 fprintf_unfiltered (gdb_stdlog
,
3408 "infrun: TARGET_WAITKIND_EXITED\n");
3410 fprintf_unfiltered (gdb_stdlog
,
3411 "infrun: TARGET_WAITKIND_SIGNALLED\n");
3414 inferior_ptid
= ecs
->ptid
;
3415 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3416 set_current_program_space (current_inferior ()->pspace
);
3417 handle_vfork_child_exec_or_exit (0);
3418 target_terminal_ours (); /* Must do this before mourn anyway. */
3420 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3422 /* Record the exit code in the convenience variable $_exitcode, so
3423 that the user can inspect this again later. */
3424 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3425 (LONGEST
) ecs
->ws
.value
.integer
);
3427 /* Also record this in the inferior itself. */
3428 current_inferior ()->has_exit_code
= 1;
3429 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3431 print_exited_reason (ecs
->ws
.value
.integer
);
3434 print_signal_exited_reason (ecs
->ws
.value
.sig
);
3436 gdb_flush (gdb_stdout
);
3437 target_mourn_inferior ();
3438 singlestep_breakpoints_inserted_p
= 0;
3439 cancel_single_step_breakpoints ();
3440 stop_print_frame
= 0;
3441 stop_stepping (ecs
);
3444 /* The following are the only cases in which we keep going;
3445 the above cases end in a continue or goto. */
3446 case TARGET_WAITKIND_FORKED
:
3447 case TARGET_WAITKIND_VFORKED
:
3450 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3451 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3453 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
3456 /* Check whether the inferior is displaced stepping. */
3458 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3459 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3460 struct displaced_step_inferior_state
*displaced
3461 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3463 /* If checking displaced stepping is supported, and thread
3464 ecs->ptid is displaced stepping. */
3465 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3467 struct inferior
*parent_inf
3468 = find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3469 struct regcache
*child_regcache
;
3470 CORE_ADDR parent_pc
;
3472 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3473 indicating that the displaced stepping of syscall instruction
3474 has been done. Perform cleanup for parent process here. Note
3475 that this operation also cleans up the child process for vfork,
3476 because their pages are shared. */
3477 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
3479 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3481 /* Restore scratch pad for child process. */
3482 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3485 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3486 the child's PC is also within the scratchpad. Set the child's PC
3487 to the parent's PC value, which has already been fixed up.
3488 FIXME: we use the parent's aspace here, although we're touching
3489 the child, because the child hasn't been added to the inferior
3490 list yet at this point. */
3493 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3495 parent_inf
->aspace
);
3496 /* Read PC value of parent process. */
3497 parent_pc
= regcache_read_pc (regcache
);
3499 if (debug_displaced
)
3500 fprintf_unfiltered (gdb_stdlog
,
3501 "displaced: write child pc from %s to %s\n",
3503 regcache_read_pc (child_regcache
)),
3504 paddress (gdbarch
, parent_pc
));
3506 regcache_write_pc (child_regcache
, parent_pc
);
3510 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3511 context_switch (ecs
->ptid
);
3513 /* Immediately detach breakpoints from the child before there's
3514 any chance of letting the user delete breakpoints from the
3515 breakpoint lists. If we don't do this early, it's easy to
3516 leave left over traps in the child, vis: "break foo; catch
3517 fork; c; <fork>; del; c; <child calls foo>". We only follow
3518 the fork on the last `continue', and by that time the
3519 breakpoint at "foo" is long gone from the breakpoint table.
3520 If we vforked, then we don't need to unpatch here, since both
3521 parent and child are sharing the same memory pages; we'll
3522 need to unpatch at follow/detach time instead to be certain
3523 that new breakpoints added between catchpoint hit time and
3524 vfork follow are detached. */
3525 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3527 /* This won't actually modify the breakpoint list, but will
3528 physically remove the breakpoints from the child. */
3529 detach_breakpoints (ecs
->ws
.value
.related_pid
);
3532 if (singlestep_breakpoints_inserted_p
)
3534 /* Pull the single step breakpoints out of the target. */
3535 remove_single_step_breakpoints ();
3536 singlestep_breakpoints_inserted_p
= 0;
3539 /* In case the event is caught by a catchpoint, remember that
3540 the event is to be followed at the next resume of the thread,
3541 and not immediately. */
3542 ecs
->event_thread
->pending_follow
= ecs
->ws
;
3544 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3546 ecs
->event_thread
->control
.stop_bpstat
3547 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3548 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3550 /* Note that we're interested in knowing the bpstat actually
3551 causes a stop, not just if it may explain the signal.
3552 Software watchpoints, for example, always appear in the
3555 = !bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
);
3557 /* If no catchpoint triggered for this, then keep going. */
3558 if (ecs
->random_signal
)
3564 = (follow_fork_mode_string
== follow_fork_mode_child
);
3566 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3568 should_resume
= follow_fork ();
3571 child
= ecs
->ws
.value
.related_pid
;
3573 /* In non-stop mode, also resume the other branch. */
3574 if (non_stop
&& !detach_fork
)
3577 switch_to_thread (parent
);
3579 switch_to_thread (child
);
3581 ecs
->event_thread
= inferior_thread ();
3582 ecs
->ptid
= inferior_ptid
;
3587 switch_to_thread (child
);
3589 switch_to_thread (parent
);
3591 ecs
->event_thread
= inferior_thread ();
3592 ecs
->ptid
= inferior_ptid
;
3597 stop_stepping (ecs
);
3600 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3601 goto process_event_stop_test
;
3603 case TARGET_WAITKIND_VFORK_DONE
:
3604 /* Done with the shared memory region. Re-insert breakpoints in
3605 the parent, and keep going. */
3608 fprintf_unfiltered (gdb_stdlog
,
3609 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3611 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3612 context_switch (ecs
->ptid
);
3614 current_inferior ()->waiting_for_vfork_done
= 0;
3615 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
3616 /* This also takes care of reinserting breakpoints in the
3617 previously locked inferior. */
3621 case TARGET_WAITKIND_EXECD
:
3623 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
3625 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3626 context_switch (ecs
->ptid
);
3628 singlestep_breakpoints_inserted_p
= 0;
3629 cancel_single_step_breakpoints ();
3631 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3633 /* Do whatever is necessary to the parent branch of the vfork. */
3634 handle_vfork_child_exec_or_exit (1);
3636 /* This causes the eventpoints and symbol table to be reset.
3637 Must do this now, before trying to determine whether to
3639 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
3641 ecs
->event_thread
->control
.stop_bpstat
3642 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3643 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3645 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3647 /* Note that this may be referenced from inside
3648 bpstat_stop_status above, through inferior_has_execd. */
3649 xfree (ecs
->ws
.value
.execd_pathname
);
3650 ecs
->ws
.value
.execd_pathname
= NULL
;
3652 /* If no catchpoint triggered for this, then keep going. */
3653 if (ecs
->random_signal
)
3655 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3659 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3660 goto process_event_stop_test
;
3662 /* Be careful not to try to gather much state about a thread
3663 that's in a syscall. It's frequently a losing proposition. */
3664 case TARGET_WAITKIND_SYSCALL_ENTRY
:
3666 fprintf_unfiltered (gdb_stdlog
,
3667 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3668 /* Getting the current syscall number. */
3669 if (handle_syscall_event (ecs
) != 0)
3671 goto process_event_stop_test
;
3673 /* Before examining the threads further, step this thread to
3674 get it entirely out of the syscall. (We get notice of the
3675 event when the thread is just on the verge of exiting a
3676 syscall. Stepping one instruction seems to get it back
3678 case TARGET_WAITKIND_SYSCALL_RETURN
:
3680 fprintf_unfiltered (gdb_stdlog
,
3681 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3682 if (handle_syscall_event (ecs
) != 0)
3684 goto process_event_stop_test
;
3686 case TARGET_WAITKIND_STOPPED
:
3688 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
3689 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
3692 case TARGET_WAITKIND_NO_HISTORY
:
3694 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
3695 /* Reverse execution: target ran out of history info. */
3697 /* Pull the single step breakpoints out of the target. */
3698 if (singlestep_breakpoints_inserted_p
)
3700 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3701 context_switch (ecs
->ptid
);
3702 remove_single_step_breakpoints ();
3703 singlestep_breakpoints_inserted_p
= 0;
3705 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3706 print_no_history_reason ();
3707 stop_stepping (ecs
);
3711 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
3713 /* Do we need to clean up the state of a thread that has
3714 completed a displaced single-step? (Doing so usually affects
3715 the PC, so do it here, before we set stop_pc.) */
3716 displaced_step_fixup (ecs
->ptid
,
3717 ecs
->event_thread
->suspend
.stop_signal
);
3719 /* If we either finished a single-step or hit a breakpoint, but
3720 the user wanted this thread to be stopped, pretend we got a
3721 SIG0 (generic unsignaled stop). */
3723 if (ecs
->event_thread
->stop_requested
3724 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3725 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3728 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3732 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3733 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3734 struct cleanup
*old_chain
= save_inferior_ptid ();
3736 inferior_ptid
= ecs
->ptid
;
3738 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
3739 paddress (gdbarch
, stop_pc
));
3740 if (target_stopped_by_watchpoint ())
3744 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
3746 if (target_stopped_data_address (¤t_target
, &addr
))
3747 fprintf_unfiltered (gdb_stdlog
,
3748 "infrun: stopped data address = %s\n",
3749 paddress (gdbarch
, addr
));
3751 fprintf_unfiltered (gdb_stdlog
,
3752 "infrun: (no data address available)\n");
3755 do_cleanups (old_chain
);
3758 if (stepping_past_singlestep_breakpoint
)
3760 gdb_assert (singlestep_breakpoints_inserted_p
);
3761 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
3762 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
3764 stepping_past_singlestep_breakpoint
= 0;
3766 /* We've either finished single-stepping past the single-step
3767 breakpoint, or stopped for some other reason. It would be nice if
3768 we could tell, but we can't reliably. */
3769 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3772 fprintf_unfiltered (gdb_stdlog
,
3773 "infrun: stepping_past_"
3774 "singlestep_breakpoint\n");
3775 /* Pull the single step breakpoints out of the target. */
3776 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3777 context_switch (ecs
->ptid
);
3778 remove_single_step_breakpoints ();
3779 singlestep_breakpoints_inserted_p
= 0;
3781 ecs
->random_signal
= 0;
3782 ecs
->event_thread
->control
.trap_expected
= 0;
3784 context_switch (saved_singlestep_ptid
);
3785 if (deprecated_context_hook
)
3786 deprecated_context_hook (pid_to_thread_id (saved_singlestep_ptid
));
3788 resume (1, GDB_SIGNAL_0
);
3789 prepare_to_wait (ecs
);
3794 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
3796 /* In non-stop mode, there's never a deferred_step_ptid set. */
3797 gdb_assert (!non_stop
);
3799 /* If we stopped for some other reason than single-stepping, ignore
3800 the fact that we were supposed to switch back. */
3801 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3804 fprintf_unfiltered (gdb_stdlog
,
3805 "infrun: handling deferred step\n");
3807 /* Pull the single step breakpoints out of the target. */
3808 if (singlestep_breakpoints_inserted_p
)
3810 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3811 context_switch (ecs
->ptid
);
3812 remove_single_step_breakpoints ();
3813 singlestep_breakpoints_inserted_p
= 0;
3816 ecs
->event_thread
->control
.trap_expected
= 0;
3818 context_switch (deferred_step_ptid
);
3819 deferred_step_ptid
= null_ptid
;
3820 /* Suppress spurious "Switching to ..." message. */
3821 previous_inferior_ptid
= inferior_ptid
;
3823 resume (1, GDB_SIGNAL_0
);
3824 prepare_to_wait (ecs
);
3828 deferred_step_ptid
= null_ptid
;
3831 /* See if a thread hit a thread-specific breakpoint that was meant for
3832 another thread. If so, then step that thread past the breakpoint,
3835 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3837 int thread_hop_needed
= 0;
3838 struct address_space
*aspace
=
3839 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
3841 /* Check if a regular breakpoint has been hit before checking
3842 for a potential single step breakpoint. Otherwise, GDB will
3843 not see this breakpoint hit when stepping onto breakpoints. */
3844 if (regular_breakpoint_inserted_here_p (aspace
, stop_pc
))
3846 ecs
->random_signal
= 0;
3847 if (!breakpoint_thread_match (aspace
, stop_pc
, ecs
->ptid
))
3848 thread_hop_needed
= 1;
3850 else if (singlestep_breakpoints_inserted_p
)
3852 /* We have not context switched yet, so this should be true
3853 no matter which thread hit the singlestep breakpoint. */
3854 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
3856 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
3858 target_pid_to_str (ecs
->ptid
));
3860 ecs
->random_signal
= 0;
3861 /* The call to in_thread_list is necessary because PTIDs sometimes
3862 change when we go from single-threaded to multi-threaded. If
3863 the singlestep_ptid is still in the list, assume that it is
3864 really different from ecs->ptid. */
3865 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
3866 && in_thread_list (singlestep_ptid
))
3868 /* If the PC of the thread we were trying to single-step
3869 has changed, discard this event (which we were going
3870 to ignore anyway), and pretend we saw that thread
3871 trap. This prevents us continuously moving the
3872 single-step breakpoint forward, one instruction at a
3873 time. If the PC has changed, then the thread we were
3874 trying to single-step has trapped or been signalled,
3875 but the event has not been reported to GDB yet.
3877 There might be some cases where this loses signal
3878 information, if a signal has arrived at exactly the
3879 same time that the PC changed, but this is the best
3880 we can do with the information available. Perhaps we
3881 should arrange to report all events for all threads
3882 when they stop, or to re-poll the remote looking for
3883 this particular thread (i.e. temporarily enable
3886 CORE_ADDR new_singlestep_pc
3887 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
3889 if (new_singlestep_pc
!= singlestep_pc
)
3891 enum gdb_signal stop_signal
;
3894 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
3895 " but expected thread advanced also\n");
3897 /* The current context still belongs to
3898 singlestep_ptid. Don't swap here, since that's
3899 the context we want to use. Just fudge our
3900 state and continue. */
3901 stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
3902 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3903 ecs
->ptid
= singlestep_ptid
;
3904 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3905 ecs
->event_thread
->suspend
.stop_signal
= stop_signal
;
3906 stop_pc
= new_singlestep_pc
;
3911 fprintf_unfiltered (gdb_stdlog
,
3912 "infrun: unexpected thread\n");
3914 thread_hop_needed
= 1;
3915 stepping_past_singlestep_breakpoint
= 1;
3916 saved_singlestep_ptid
= singlestep_ptid
;
3921 if (thread_hop_needed
)
3923 struct regcache
*thread_regcache
;
3924 int remove_status
= 0;
3927 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
3929 /* Switch context before touching inferior memory, the
3930 previous thread may have exited. */
3931 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
3932 context_switch (ecs
->ptid
);
3934 /* Saw a breakpoint, but it was hit by the wrong thread.
3937 if (singlestep_breakpoints_inserted_p
)
3939 /* Pull the single step breakpoints out of the target. */
3940 remove_single_step_breakpoints ();
3941 singlestep_breakpoints_inserted_p
= 0;
3944 /* If the arch can displace step, don't remove the
3946 thread_regcache
= get_thread_regcache (ecs
->ptid
);
3947 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
3948 remove_status
= remove_breakpoints ();
3950 /* Did we fail to remove breakpoints? If so, try
3951 to set the PC past the bp. (There's at least
3952 one situation in which we can fail to remove
3953 the bp's: On HP-UX's that use ttrace, we can't
3954 change the address space of a vforking child
3955 process until the child exits (well, okay, not
3956 then either :-) or execs. */
3957 if (remove_status
!= 0)
3958 error (_("Cannot step over breakpoint hit in wrong thread"));
3963 /* Only need to require the next event from this
3964 thread in all-stop mode. */
3965 waiton_ptid
= ecs
->ptid
;
3966 infwait_state
= infwait_thread_hop_state
;
3969 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3974 else if (singlestep_breakpoints_inserted_p
)
3976 ecs
->random_signal
= 0;
3980 ecs
->random_signal
= 1;
3982 /* See if something interesting happened to the non-current thread. If
3983 so, then switch to that thread. */
3984 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3987 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
3989 context_switch (ecs
->ptid
);
3991 if (deprecated_context_hook
)
3992 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3995 /* At this point, get hold of the now-current thread's frame. */
3996 frame
= get_current_frame ();
3997 gdbarch
= get_frame_arch (frame
);
3999 if (singlestep_breakpoints_inserted_p
)
4001 /* Pull the single step breakpoints out of the target. */
4002 remove_single_step_breakpoints ();
4003 singlestep_breakpoints_inserted_p
= 0;
4006 if (stepped_after_stopped_by_watchpoint
)
4007 stopped_by_watchpoint
= 0;
4009 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
4011 /* If necessary, step over this watchpoint. We'll be back to display
4013 if (stopped_by_watchpoint
4014 && (target_have_steppable_watchpoint
4015 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
4017 /* At this point, we are stopped at an instruction which has
4018 attempted to write to a piece of memory under control of
4019 a watchpoint. The instruction hasn't actually executed
4020 yet. If we were to evaluate the watchpoint expression
4021 now, we would get the old value, and therefore no change
4022 would seem to have occurred.
4024 In order to make watchpoints work `right', we really need
4025 to complete the memory write, and then evaluate the
4026 watchpoint expression. We do this by single-stepping the
4029 It may not be necessary to disable the watchpoint to stop over
4030 it. For example, the PA can (with some kernel cooperation)
4031 single step over a watchpoint without disabling the watchpoint.
4033 It is far more common to need to disable a watchpoint to step
4034 the inferior over it. If we have non-steppable watchpoints,
4035 we must disable the current watchpoint; it's simplest to
4036 disable all watchpoints and breakpoints. */
4039 if (!target_have_steppable_watchpoint
)
4041 remove_breakpoints ();
4042 /* See comment in resume why we need to stop bypassing signals
4043 while breakpoints have been removed. */
4044 target_pass_signals (0, NULL
);
4047 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
4048 target_resume (ecs
->ptid
, hw_step
, GDB_SIGNAL_0
);
4049 waiton_ptid
= ecs
->ptid
;
4050 if (target_have_steppable_watchpoint
)
4051 infwait_state
= infwait_step_watch_state
;
4053 infwait_state
= infwait_nonstep_watch_state
;
4054 prepare_to_wait (ecs
);
4058 clear_stop_func (ecs
);
4059 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4060 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4061 ecs
->event_thread
->control
.stop_step
= 0;
4062 stop_print_frame
= 1;
4063 ecs
->random_signal
= 0;
4064 stopped_by_random_signal
= 0;
4066 /* Hide inlined functions starting here, unless we just performed stepi or
4067 nexti. After stepi and nexti, always show the innermost frame (not any
4068 inline function call sites). */
4069 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4071 struct address_space
*aspace
=
4072 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4074 /* skip_inline_frames is expensive, so we avoid it if we can
4075 determine that the address is one where functions cannot have
4076 been inlined. This improves performance with inferiors that
4077 load a lot of shared libraries, because the solib event
4078 breakpoint is defined as the address of a function (i.e. not
4079 inline). Note that we have to check the previous PC as well
4080 as the current one to catch cases when we have just
4081 single-stepped off a breakpoint prior to reinstating it.
4082 Note that we're assuming that the code we single-step to is
4083 not inline, but that's not definitive: there's nothing
4084 preventing the event breakpoint function from containing
4085 inlined code, and the single-step ending up there. If the
4086 user had set a breakpoint on that inlined code, the missing
4087 skip_inline_frames call would break things. Fortunately
4088 that's an extremely unlikely scenario. */
4089 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4090 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4091 && ecs
->event_thread
->control
.trap_expected
4092 && pc_at_non_inline_function (aspace
,
4093 ecs
->event_thread
->prev_pc
,
4096 skip_inline_frames (ecs
->ptid
);
4098 /* Re-fetch current thread's frame in case that invalidated
4100 frame
= get_current_frame ();
4101 gdbarch
= get_frame_arch (frame
);
4105 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4106 && ecs
->event_thread
->control
.trap_expected
4107 && gdbarch_single_step_through_delay_p (gdbarch
)
4108 && currently_stepping (ecs
->event_thread
))
4110 /* We're trying to step off a breakpoint. Turns out that we're
4111 also on an instruction that needs to be stepped multiple
4112 times before it's been fully executing. E.g., architectures
4113 with a delay slot. It needs to be stepped twice, once for
4114 the instruction and once for the delay slot. */
4115 int step_through_delay
4116 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4118 if (debug_infrun
&& step_through_delay
)
4119 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4120 if (ecs
->event_thread
->control
.step_range_end
== 0
4121 && step_through_delay
)
4123 /* The user issued a continue when stopped at a breakpoint.
4124 Set up for another trap and get out of here. */
4125 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4129 else if (step_through_delay
)
4131 /* The user issued a step when stopped at a breakpoint.
4132 Maybe we should stop, maybe we should not - the delay
4133 slot *might* correspond to a line of source. In any
4134 case, don't decide that here, just set
4135 ecs->stepping_over_breakpoint, making sure we
4136 single-step again before breakpoints are re-inserted. */
4137 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4141 /* Look at the cause of the stop, and decide what to do.
4142 The alternatives are:
4143 1) stop_stepping and return; to really stop and return to the debugger,
4144 2) keep_going and return to start up again
4145 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
4146 3) set ecs->random_signal to 1, and the decision between 1 and 2
4147 will be made according to the signal handling tables. */
4149 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4150 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4151 || stop_soon
== STOP_QUIETLY_REMOTE
)
4153 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4157 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4158 stop_print_frame
= 0;
4159 stop_stepping (ecs
);
4163 /* This is originated from start_remote(), start_inferior() and
4164 shared libraries hook functions. */
4165 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4168 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4169 stop_stepping (ecs
);
4173 /* This originates from attach_command(). We need to overwrite
4174 the stop_signal here, because some kernels don't ignore a
4175 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4176 See more comments in inferior.h. On the other hand, if we
4177 get a non-SIGSTOP, report it to the user - assume the backend
4178 will handle the SIGSTOP if it should show up later.
4180 Also consider that the attach is complete when we see a
4181 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4182 target extended-remote report it instead of a SIGSTOP
4183 (e.g. gdbserver). We already rely on SIGTRAP being our
4184 signal, so this is no exception.
4186 Also consider that the attach is complete when we see a
4187 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4188 the target to stop all threads of the inferior, in case the
4189 low level attach operation doesn't stop them implicitly. If
4190 they weren't stopped implicitly, then the stub will report a
4191 GDB_SIGNAL_0, meaning: stopped for no particular reason
4192 other than GDB's request. */
4193 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4194 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
4195 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4196 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
4198 stop_stepping (ecs
);
4199 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4203 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4204 handles this event. */
4205 ecs
->event_thread
->control
.stop_bpstat
4206 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4207 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4209 /* Following in case break condition called a
4211 stop_print_frame
= 1;
4213 /* This is where we handle "moribund" watchpoints. Unlike
4214 software breakpoints traps, hardware watchpoint traps are
4215 always distinguishable from random traps. If no high-level
4216 watchpoint is associated with the reported stop data address
4217 anymore, then the bpstat does not explain the signal ---
4218 simply make sure to ignore it if `stopped_by_watchpoint' is
4222 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4223 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4224 && stopped_by_watchpoint
)
4225 fprintf_unfiltered (gdb_stdlog
,
4226 "infrun: no user watchpoint explains "
4227 "watchpoint SIGTRAP, ignoring\n");
4229 /* NOTE: cagney/2003-03-29: These two checks for a random signal
4230 at one stage in the past included checks for an inferior
4231 function call's call dummy's return breakpoint. The original
4232 comment, that went with the test, read:
4234 ``End of a stack dummy. Some systems (e.g. Sony news) give
4235 another signal besides SIGTRAP, so check here as well as
4238 If someone ever tries to get call dummys on a
4239 non-executable stack to work (where the target would stop
4240 with something like a SIGSEGV), then those tests might need
4241 to be re-instated. Given, however, that the tests were only
4242 enabled when momentary breakpoints were not being used, I
4243 suspect that it won't be the case.
4245 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4246 be necessary for call dummies on a non-executable stack on
4249 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4251 = !(bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4252 || stopped_by_watchpoint
4253 || ecs
->event_thread
->control
.trap_expected
4254 || (ecs
->event_thread
->control
.step_range_end
4255 && (ecs
->event_thread
->control
.step_resume_breakpoint
4259 ecs
->random_signal
= !bpstat_explains_signal
4260 (ecs
->event_thread
->control
.stop_bpstat
);
4261 if (!ecs
->random_signal
)
4262 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
4266 /* When we reach this point, we've pretty much decided
4267 that the reason for stopping must've been a random
4268 (unexpected) signal. */
4271 ecs
->random_signal
= 1;
4273 process_event_stop_test
:
4275 /* Re-fetch current thread's frame in case we did a
4276 "goto process_event_stop_test" above. */
4277 frame
= get_current_frame ();
4278 gdbarch
= get_frame_arch (frame
);
4280 /* For the program's own signals, act according to
4281 the signal handling tables. */
4283 if (ecs
->random_signal
)
4285 /* Signal not for debugging purposes. */
4287 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
4290 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
4291 ecs
->event_thread
->suspend
.stop_signal
);
4293 stopped_by_random_signal
= 1;
4295 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4298 target_terminal_ours_for_output ();
4299 print_signal_received_reason
4300 (ecs
->event_thread
->suspend
.stop_signal
);
4302 /* Always stop on signals if we're either just gaining control
4303 of the program, or the user explicitly requested this thread
4304 to remain stopped. */
4305 if (stop_soon
!= NO_STOP_QUIETLY
4306 || ecs
->event_thread
->stop_requested
4308 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4310 stop_stepping (ecs
);
4313 /* If not going to stop, give terminal back
4314 if we took it away. */
4316 target_terminal_inferior ();
4318 /* Clear the signal if it should not be passed. */
4319 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4320 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4322 if (ecs
->event_thread
->prev_pc
== stop_pc
4323 && ecs
->event_thread
->control
.trap_expected
4324 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4326 /* We were just starting a new sequence, attempting to
4327 single-step off of a breakpoint and expecting a SIGTRAP.
4328 Instead this signal arrives. This signal will take us out
4329 of the stepping range so GDB needs to remember to, when
4330 the signal handler returns, resume stepping off that
4332 /* To simplify things, "continue" is forced to use the same
4333 code paths as single-step - set a breakpoint at the
4334 signal return address and then, once hit, step off that
4337 fprintf_unfiltered (gdb_stdlog
,
4338 "infrun: signal arrived while stepping over "
4341 insert_hp_step_resume_breakpoint_at_frame (frame
);
4342 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4343 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4344 ecs
->event_thread
->control
.trap_expected
= 0;
4349 if (ecs
->event_thread
->control
.step_range_end
!= 0
4350 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4351 && (ecs
->event_thread
->control
.step_range_start
<= stop_pc
4352 && stop_pc
< ecs
->event_thread
->control
.step_range_end
)
4353 && frame_id_eq (get_stack_frame_id (frame
),
4354 ecs
->event_thread
->control
.step_stack_frame_id
)
4355 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4357 /* The inferior is about to take a signal that will take it
4358 out of the single step range. Set a breakpoint at the
4359 current PC (which is presumably where the signal handler
4360 will eventually return) and then allow the inferior to
4363 Note that this is only needed for a signal delivered
4364 while in the single-step range. Nested signals aren't a
4365 problem as they eventually all return. */
4367 fprintf_unfiltered (gdb_stdlog
,
4368 "infrun: signal may take us out of "
4369 "single-step range\n");
4371 insert_hp_step_resume_breakpoint_at_frame (frame
);
4372 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4373 ecs
->event_thread
->control
.trap_expected
= 0;
4378 /* Note: step_resume_breakpoint may be non-NULL. This occures
4379 when either there's a nested signal, or when there's a
4380 pending signal enabled just as the signal handler returns
4381 (leaving the inferior at the step-resume-breakpoint without
4382 actually executing it). Either way continue until the
4383 breakpoint is really hit. */
4387 /* Handle cases caused by hitting a breakpoint. */
4389 CORE_ADDR jmp_buf_pc
;
4390 struct bpstat_what what
;
4392 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4394 if (what
.call_dummy
)
4396 stop_stack_dummy
= what
.call_dummy
;
4399 /* If we hit an internal event that triggers symbol changes, the
4400 current frame will be invalidated within bpstat_what (e.g.,
4401 if we hit an internal solib event). Re-fetch it. */
4402 frame
= get_current_frame ();
4403 gdbarch
= get_frame_arch (frame
);
4405 switch (what
.main_action
)
4407 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4408 /* If we hit the breakpoint at longjmp while stepping, we
4409 install a momentary breakpoint at the target of the
4413 fprintf_unfiltered (gdb_stdlog
,
4414 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4416 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4418 if (what
.is_longjmp
)
4420 struct value
*arg_value
;
4422 /* If we set the longjmp breakpoint via a SystemTap
4423 probe, then use it to extract the arguments. The
4424 destination PC is the third argument to the
4426 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4428 jmp_buf_pc
= value_as_address (arg_value
);
4429 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4430 || !gdbarch_get_longjmp_target (gdbarch
,
4431 frame
, &jmp_buf_pc
))
4434 fprintf_unfiltered (gdb_stdlog
,
4435 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4436 "(!gdbarch_get_longjmp_target)\n");
4441 /* Insert a breakpoint at resume address. */
4442 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4445 check_exception_resume (ecs
, frame
);
4449 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4451 struct frame_info
*init_frame
;
4453 /* There are several cases to consider.
4455 1. The initiating frame no longer exists. In this case
4456 we must stop, because the exception or longjmp has gone
4459 2. The initiating frame exists, and is the same as the
4460 current frame. We stop, because the exception or
4461 longjmp has been caught.
4463 3. The initiating frame exists and is different from
4464 the current frame. This means the exception or longjmp
4465 has been caught beneath the initiating frame, so keep
4468 4. longjmp breakpoint has been placed just to protect
4469 against stale dummy frames and user is not interested
4470 in stopping around longjmps. */
4473 fprintf_unfiltered (gdb_stdlog
,
4474 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4476 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4478 delete_exception_resume_breakpoint (ecs
->event_thread
);
4480 if (what
.is_longjmp
)
4482 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
->num
);
4484 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
4492 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4496 struct frame_id current_id
4497 = get_frame_id (get_current_frame ());
4498 if (frame_id_eq (current_id
,
4499 ecs
->event_thread
->initiating_frame
))
4501 /* Case 2. Fall through. */
4511 /* For Cases 1 and 2, remove the step-resume breakpoint,
4513 delete_step_resume_breakpoint (ecs
->event_thread
);
4515 ecs
->event_thread
->control
.stop_step
= 1;
4516 print_end_stepping_range_reason ();
4517 stop_stepping (ecs
);
4521 case BPSTAT_WHAT_SINGLE
:
4523 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4524 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4525 /* Still need to check other stuff, at least the case where
4526 we are stepping and step out of the right range. */
4529 case BPSTAT_WHAT_STEP_RESUME
:
4531 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4533 delete_step_resume_breakpoint (ecs
->event_thread
);
4534 if (ecs
->event_thread
->control
.proceed_to_finish
4535 && execution_direction
== EXEC_REVERSE
)
4537 struct thread_info
*tp
= ecs
->event_thread
;
4539 /* We are finishing a function in reverse, and just hit
4540 the step-resume breakpoint at the start address of
4541 the function, and we're almost there -- just need to
4542 back up by one more single-step, which should take us
4543 back to the function call. */
4544 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4548 fill_in_stop_func (gdbarch
, ecs
);
4549 if (stop_pc
== ecs
->stop_func_start
4550 && execution_direction
== EXEC_REVERSE
)
4552 /* We are stepping over a function call in reverse, and
4553 just hit the step-resume breakpoint at the start
4554 address of the function. Go back to single-stepping,
4555 which should take us back to the function call. */
4556 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4562 case BPSTAT_WHAT_STOP_NOISY
:
4564 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4565 stop_print_frame
= 1;
4567 /* We are about to nuke the step_resume_breakpointt via the
4568 cleanup chain, so no need to worry about it here. */
4570 stop_stepping (ecs
);
4573 case BPSTAT_WHAT_STOP_SILENT
:
4575 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4576 stop_print_frame
= 0;
4578 /* We are about to nuke the step_resume_breakpoin via the
4579 cleanup chain, so no need to worry about it here. */
4581 stop_stepping (ecs
);
4584 case BPSTAT_WHAT_HP_STEP_RESUME
:
4586 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4588 delete_step_resume_breakpoint (ecs
->event_thread
);
4589 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4591 /* Back when the step-resume breakpoint was inserted, we
4592 were trying to single-step off a breakpoint. Go back
4594 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4595 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4601 case BPSTAT_WHAT_KEEP_CHECKING
:
4606 /* We come here if we hit a breakpoint but should not
4607 stop for it. Possibly we also were stepping
4608 and should stop for that. So fall through and
4609 test for stepping. But, if not stepping,
4612 /* In all-stop mode, if we're currently stepping but have stopped in
4613 some other thread, we need to switch back to the stepped thread. */
4616 struct thread_info
*tp
;
4618 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
4622 /* However, if the current thread is blocked on some internal
4623 breakpoint, and we simply need to step over that breakpoint
4624 to get it going again, do that first. */
4625 if ((ecs
->event_thread
->control
.trap_expected
4626 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
4627 || ecs
->event_thread
->stepping_over_breakpoint
)
4633 /* If the stepping thread exited, then don't try to switch
4634 back and resume it, which could fail in several different
4635 ways depending on the target. Instead, just keep going.
4637 We can find a stepping dead thread in the thread list in
4640 - The target supports thread exit events, and when the
4641 target tries to delete the thread from the thread list,
4642 inferior_ptid pointed at the exiting thread. In such
4643 case, calling delete_thread does not really remove the
4644 thread from the list; instead, the thread is left listed,
4645 with 'exited' state.
4647 - The target's debug interface does not support thread
4648 exit events, and so we have no idea whatsoever if the
4649 previously stepping thread is still alive. For that
4650 reason, we need to synchronously query the target
4652 if (is_exited (tp
->ptid
)
4653 || !target_thread_alive (tp
->ptid
))
4656 fprintf_unfiltered (gdb_stdlog
,
4657 "infrun: not switching back to "
4658 "stepped thread, it has vanished\n");
4660 delete_thread (tp
->ptid
);
4665 /* Otherwise, we no longer expect a trap in the current thread.
4666 Clear the trap_expected flag before switching back -- this is
4667 what keep_going would do as well, if we called it. */
4668 ecs
->event_thread
->control
.trap_expected
= 0;
4671 fprintf_unfiltered (gdb_stdlog
,
4672 "infrun: switching back to stepped thread\n");
4674 ecs
->event_thread
= tp
;
4675 ecs
->ptid
= tp
->ptid
;
4676 context_switch (ecs
->ptid
);
4682 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4685 fprintf_unfiltered (gdb_stdlog
,
4686 "infrun: step-resume breakpoint is inserted\n");
4688 /* Having a step-resume breakpoint overrides anything
4689 else having to do with stepping commands until
4690 that breakpoint is reached. */
4695 if (ecs
->event_thread
->control
.step_range_end
== 0)
4698 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4699 /* Likewise if we aren't even stepping. */
4704 /* Re-fetch current thread's frame in case the code above caused
4705 the frame cache to be re-initialized, making our FRAME variable
4706 a dangling pointer. */
4707 frame
= get_current_frame ();
4708 gdbarch
= get_frame_arch (frame
);
4709 fill_in_stop_func (gdbarch
, ecs
);
4711 /* If stepping through a line, keep going if still within it.
4713 Note that step_range_end is the address of the first instruction
4714 beyond the step range, and NOT the address of the last instruction
4717 Note also that during reverse execution, we may be stepping
4718 through a function epilogue and therefore must detect when
4719 the current-frame changes in the middle of a line. */
4721 if (stop_pc
>= ecs
->event_thread
->control
.step_range_start
4722 && stop_pc
< ecs
->event_thread
->control
.step_range_end
4723 && (execution_direction
!= EXEC_REVERSE
4724 || frame_id_eq (get_frame_id (frame
),
4725 ecs
->event_thread
->control
.step_frame_id
)))
4729 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4730 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4731 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4733 /* When stepping backward, stop at beginning of line range
4734 (unless it's the function entry point, in which case
4735 keep going back to the call point). */
4736 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4737 && stop_pc
!= ecs
->stop_func_start
4738 && execution_direction
== EXEC_REVERSE
)
4740 ecs
->event_thread
->control
.stop_step
= 1;
4741 print_end_stepping_range_reason ();
4742 stop_stepping (ecs
);
4750 /* We stepped out of the stepping range. */
4752 /* If we are stepping at the source level and entered the runtime
4753 loader dynamic symbol resolution code...
4755 EXEC_FORWARD: we keep on single stepping until we exit the run
4756 time loader code and reach the callee's address.
4758 EXEC_REVERSE: we've already executed the callee (backward), and
4759 the runtime loader code is handled just like any other
4760 undebuggable function call. Now we need only keep stepping
4761 backward through the trampoline code, and that's handled further
4762 down, so there is nothing for us to do here. */
4764 if (execution_direction
!= EXEC_REVERSE
4765 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4766 && in_solib_dynsym_resolve_code (stop_pc
))
4768 CORE_ADDR pc_after_resolver
=
4769 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
4772 fprintf_unfiltered (gdb_stdlog
,
4773 "infrun: stepped into dynsym resolve code\n");
4775 if (pc_after_resolver
)
4777 /* Set up a step-resume breakpoint at the address
4778 indicated by SKIP_SOLIB_RESOLVER. */
4779 struct symtab_and_line sr_sal
;
4782 sr_sal
.pc
= pc_after_resolver
;
4783 sr_sal
.pspace
= get_frame_program_space (frame
);
4785 insert_step_resume_breakpoint_at_sal (gdbarch
,
4786 sr_sal
, null_frame_id
);
4793 if (ecs
->event_thread
->control
.step_range_end
!= 1
4794 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4795 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4796 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
4799 fprintf_unfiltered (gdb_stdlog
,
4800 "infrun: stepped into signal trampoline\n");
4801 /* The inferior, while doing a "step" or "next", has ended up in
4802 a signal trampoline (either by a signal being delivered or by
4803 the signal handler returning). Just single-step until the
4804 inferior leaves the trampoline (either by calling the handler
4810 /* If we're in the return path from a shared library trampoline,
4811 we want to proceed through the trampoline when stepping. */
4812 /* macro/2012-04-25: This needs to come before the subroutine
4813 call check below as on some targets return trampolines look
4814 like subroutine calls (MIPS16 return thunks). */
4815 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4816 stop_pc
, ecs
->stop_func_name
)
4817 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
4819 /* Determine where this trampoline returns. */
4820 CORE_ADDR real_stop_pc
;
4822 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4825 fprintf_unfiltered (gdb_stdlog
,
4826 "infrun: stepped into solib return tramp\n");
4828 /* Only proceed through if we know where it's going. */
4831 /* And put the step-breakpoint there and go until there. */
4832 struct symtab_and_line sr_sal
;
4834 init_sal (&sr_sal
); /* initialize to zeroes */
4835 sr_sal
.pc
= real_stop_pc
;
4836 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4837 sr_sal
.pspace
= get_frame_program_space (frame
);
4839 /* Do not specify what the fp should be when we stop since
4840 on some machines the prologue is where the new fp value
4842 insert_step_resume_breakpoint_at_sal (gdbarch
,
4843 sr_sal
, null_frame_id
);
4845 /* Restart without fiddling with the step ranges or
4852 /* Check for subroutine calls. The check for the current frame
4853 equalling the step ID is not necessary - the check of the
4854 previous frame's ID is sufficient - but it is a common case and
4855 cheaper than checking the previous frame's ID.
4857 NOTE: frame_id_eq will never report two invalid frame IDs as
4858 being equal, so to get into this block, both the current and
4859 previous frame must have valid frame IDs. */
4860 /* The outer_frame_id check is a heuristic to detect stepping
4861 through startup code. If we step over an instruction which
4862 sets the stack pointer from an invalid value to a valid value,
4863 we may detect that as a subroutine call from the mythical
4864 "outermost" function. This could be fixed by marking
4865 outermost frames as !stack_p,code_p,special_p. Then the
4866 initial outermost frame, before sp was valid, would
4867 have code_addr == &_start. See the comment in frame_id_eq
4869 if (!frame_id_eq (get_stack_frame_id (frame
),
4870 ecs
->event_thread
->control
.step_stack_frame_id
)
4871 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4872 ecs
->event_thread
->control
.step_stack_frame_id
)
4873 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
4875 || step_start_function
!= find_pc_function (stop_pc
))))
4877 CORE_ADDR real_stop_pc
;
4880 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
4882 if ((ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
4883 || ((ecs
->event_thread
->control
.step_range_end
== 1)
4884 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
4885 ecs
->stop_func_start
)))
4887 /* I presume that step_over_calls is only 0 when we're
4888 supposed to be stepping at the assembly language level
4889 ("stepi"). Just stop. */
4890 /* Also, maybe we just did a "nexti" inside a prolog, so we
4891 thought it was a subroutine call but it was not. Stop as
4893 /* And this works the same backward as frontward. MVS */
4894 ecs
->event_thread
->control
.stop_step
= 1;
4895 print_end_stepping_range_reason ();
4896 stop_stepping (ecs
);
4900 /* Reverse stepping through solib trampolines. */
4902 if (execution_direction
== EXEC_REVERSE
4903 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
4904 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4905 || (ecs
->stop_func_start
== 0
4906 && in_solib_dynsym_resolve_code (stop_pc
))))
4908 /* Any solib trampoline code can be handled in reverse
4909 by simply continuing to single-step. We have already
4910 executed the solib function (backwards), and a few
4911 steps will take us back through the trampoline to the
4917 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4919 /* We're doing a "next".
4921 Normal (forward) execution: set a breakpoint at the
4922 callee's return address (the address at which the caller
4925 Reverse (backward) execution. set the step-resume
4926 breakpoint at the start of the function that we just
4927 stepped into (backwards), and continue to there. When we
4928 get there, we'll need to single-step back to the caller. */
4930 if (execution_direction
== EXEC_REVERSE
)
4932 /* If we're already at the start of the function, we've either
4933 just stepped backward into a single instruction function,
4934 or stepped back out of a signal handler to the first instruction
4935 of the function. Just keep going, which will single-step back
4937 if (ecs
->stop_func_start
!= stop_pc
)
4939 struct symtab_and_line sr_sal
;
4941 /* Normal function call return (static or dynamic). */
4943 sr_sal
.pc
= ecs
->stop_func_start
;
4944 sr_sal
.pspace
= get_frame_program_space (frame
);
4945 insert_step_resume_breakpoint_at_sal (gdbarch
,
4946 sr_sal
, null_frame_id
);
4950 insert_step_resume_breakpoint_at_caller (frame
);
4956 /* If we are in a function call trampoline (a stub between the
4957 calling routine and the real function), locate the real
4958 function. That's what tells us (a) whether we want to step
4959 into it at all, and (b) what prologue we want to run to the
4960 end of, if we do step into it. */
4961 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
4962 if (real_stop_pc
== 0)
4963 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4964 if (real_stop_pc
!= 0)
4965 ecs
->stop_func_start
= real_stop_pc
;
4967 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
4969 struct symtab_and_line sr_sal
;
4972 sr_sal
.pc
= ecs
->stop_func_start
;
4973 sr_sal
.pspace
= get_frame_program_space (frame
);
4975 insert_step_resume_breakpoint_at_sal (gdbarch
,
4976 sr_sal
, null_frame_id
);
4981 /* If we have line number information for the function we are
4982 thinking of stepping into and the function isn't on the skip
4985 If there are several symtabs at that PC (e.g. with include
4986 files), just want to know whether *any* of them have line
4987 numbers. find_pc_line handles this. */
4989 struct symtab_and_line tmp_sal
;
4991 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4992 if (tmp_sal
.line
!= 0
4993 && !function_pc_is_marked_for_skip (ecs
->stop_func_start
))
4995 if (execution_direction
== EXEC_REVERSE
)
4996 handle_step_into_function_backward (gdbarch
, ecs
);
4998 handle_step_into_function (gdbarch
, ecs
);
5003 /* If we have no line number and the step-stop-if-no-debug is
5004 set, we stop the step so that the user has a chance to switch
5005 in assembly mode. */
5006 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5007 && step_stop_if_no_debug
)
5009 ecs
->event_thread
->control
.stop_step
= 1;
5010 print_end_stepping_range_reason ();
5011 stop_stepping (ecs
);
5015 if (execution_direction
== EXEC_REVERSE
)
5017 /* If we're already at the start of the function, we've either just
5018 stepped backward into a single instruction function without line
5019 number info, or stepped back out of a signal handler to the first
5020 instruction of the function without line number info. Just keep
5021 going, which will single-step back to the caller. */
5022 if (ecs
->stop_func_start
!= stop_pc
)
5024 /* Set a breakpoint at callee's start address.
5025 From there we can step once and be back in the caller. */
5026 struct symtab_and_line sr_sal
;
5029 sr_sal
.pc
= ecs
->stop_func_start
;
5030 sr_sal
.pspace
= get_frame_program_space (frame
);
5031 insert_step_resume_breakpoint_at_sal (gdbarch
,
5032 sr_sal
, null_frame_id
);
5036 /* Set a breakpoint at callee's return address (the address
5037 at which the caller will resume). */
5038 insert_step_resume_breakpoint_at_caller (frame
);
5044 /* Reverse stepping through solib trampolines. */
5046 if (execution_direction
== EXEC_REVERSE
5047 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5049 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5050 || (ecs
->stop_func_start
== 0
5051 && in_solib_dynsym_resolve_code (stop_pc
)))
5053 /* Any solib trampoline code can be handled in reverse
5054 by simply continuing to single-step. We have already
5055 executed the solib function (backwards), and a few
5056 steps will take us back through the trampoline to the
5061 else if (in_solib_dynsym_resolve_code (stop_pc
))
5063 /* Stepped backward into the solib dynsym resolver.
5064 Set a breakpoint at its start and continue, then
5065 one more step will take us out. */
5066 struct symtab_and_line sr_sal
;
5069 sr_sal
.pc
= ecs
->stop_func_start
;
5070 sr_sal
.pspace
= get_frame_program_space (frame
);
5071 insert_step_resume_breakpoint_at_sal (gdbarch
,
5072 sr_sal
, null_frame_id
);
5078 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5080 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5081 the trampoline processing logic, however, there are some trampolines
5082 that have no names, so we should do trampoline handling first. */
5083 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5084 && ecs
->stop_func_name
== NULL
5085 && stop_pc_sal
.line
== 0)
5088 fprintf_unfiltered (gdb_stdlog
,
5089 "infrun: stepped into undebuggable function\n");
5091 /* The inferior just stepped into, or returned to, an
5092 undebuggable function (where there is no debugging information
5093 and no line number corresponding to the address where the
5094 inferior stopped). Since we want to skip this kind of code,
5095 we keep going until the inferior returns from this
5096 function - unless the user has asked us not to (via
5097 set step-mode) or we no longer know how to get back
5098 to the call site. */
5099 if (step_stop_if_no_debug
5100 || !frame_id_p (frame_unwind_caller_id (frame
)))
5102 /* If we have no line number and the step-stop-if-no-debug
5103 is set, we stop the step so that the user has a chance to
5104 switch in assembly mode. */
5105 ecs
->event_thread
->control
.stop_step
= 1;
5106 print_end_stepping_range_reason ();
5107 stop_stepping (ecs
);
5112 /* Set a breakpoint at callee's return address (the address
5113 at which the caller will resume). */
5114 insert_step_resume_breakpoint_at_caller (frame
);
5120 if (ecs
->event_thread
->control
.step_range_end
== 1)
5122 /* It is stepi or nexti. We always want to stop stepping after
5125 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5126 ecs
->event_thread
->control
.stop_step
= 1;
5127 print_end_stepping_range_reason ();
5128 stop_stepping (ecs
);
5132 if (stop_pc_sal
.line
== 0)
5134 /* We have no line number information. That means to stop
5135 stepping (does this always happen right after one instruction,
5136 when we do "s" in a function with no line numbers,
5137 or can this happen as a result of a return or longjmp?). */
5139 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5140 ecs
->event_thread
->control
.stop_step
= 1;
5141 print_end_stepping_range_reason ();
5142 stop_stepping (ecs
);
5146 /* Look for "calls" to inlined functions, part one. If the inline
5147 frame machinery detected some skipped call sites, we have entered
5148 a new inline function. */
5150 if (frame_id_eq (get_frame_id (get_current_frame ()),
5151 ecs
->event_thread
->control
.step_frame_id
)
5152 && inline_skipped_frames (ecs
->ptid
))
5154 struct symtab_and_line call_sal
;
5157 fprintf_unfiltered (gdb_stdlog
,
5158 "infrun: stepped into inlined function\n");
5160 find_frame_sal (get_current_frame (), &call_sal
);
5162 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5164 /* For "step", we're going to stop. But if the call site
5165 for this inlined function is on the same source line as
5166 we were previously stepping, go down into the function
5167 first. Otherwise stop at the call site. */
5169 if (call_sal
.line
== ecs
->event_thread
->current_line
5170 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5171 step_into_inline_frame (ecs
->ptid
);
5173 ecs
->event_thread
->control
.stop_step
= 1;
5174 print_end_stepping_range_reason ();
5175 stop_stepping (ecs
);
5180 /* For "next", we should stop at the call site if it is on a
5181 different source line. Otherwise continue through the
5182 inlined function. */
5183 if (call_sal
.line
== ecs
->event_thread
->current_line
5184 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5188 ecs
->event_thread
->control
.stop_step
= 1;
5189 print_end_stepping_range_reason ();
5190 stop_stepping (ecs
);
5196 /* Look for "calls" to inlined functions, part two. If we are still
5197 in the same real function we were stepping through, but we have
5198 to go further up to find the exact frame ID, we are stepping
5199 through a more inlined call beyond its call site. */
5201 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5202 && !frame_id_eq (get_frame_id (get_current_frame ()),
5203 ecs
->event_thread
->control
.step_frame_id
)
5204 && stepped_in_from (get_current_frame (),
5205 ecs
->event_thread
->control
.step_frame_id
))
5208 fprintf_unfiltered (gdb_stdlog
,
5209 "infrun: stepping through inlined function\n");
5211 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5215 ecs
->event_thread
->control
.stop_step
= 1;
5216 print_end_stepping_range_reason ();
5217 stop_stepping (ecs
);
5222 if ((stop_pc
== stop_pc_sal
.pc
)
5223 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5224 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5226 /* We are at the start of a different line. So stop. Note that
5227 we don't stop if we step into the middle of a different line.
5228 That is said to make things like for (;;) statements work
5231 fprintf_unfiltered (gdb_stdlog
,
5232 "infrun: stepped to a different line\n");
5233 ecs
->event_thread
->control
.stop_step
= 1;
5234 print_end_stepping_range_reason ();
5235 stop_stepping (ecs
);
5239 /* We aren't done stepping.
5241 Optimize by setting the stepping range to the line.
5242 (We might not be in the original line, but if we entered a
5243 new line in mid-statement, we continue stepping. This makes
5244 things like for(;;) statements work better.) */
5246 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5247 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5248 set_step_info (frame
, stop_pc_sal
);
5251 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5255 /* Is thread TP in the middle of single-stepping? */
5258 currently_stepping (struct thread_info
*tp
)
5260 return ((tp
->control
.step_range_end
5261 && tp
->control
.step_resume_breakpoint
== NULL
)
5262 || tp
->control
.trap_expected
5263 || bpstat_should_step ());
5266 /* Returns true if any thread *but* the one passed in "data" is in the
5267 middle of stepping or of handling a "next". */
5270 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
5275 return (tp
->control
.step_range_end
5276 || tp
->control
.trap_expected
);
5279 /* Inferior has stepped into a subroutine call with source code that
5280 we should not step over. Do step to the first line of code in
5284 handle_step_into_function (struct gdbarch
*gdbarch
,
5285 struct execution_control_state
*ecs
)
5288 struct symtab_and_line stop_func_sal
, sr_sal
;
5290 fill_in_stop_func (gdbarch
, ecs
);
5292 s
= find_pc_symtab (stop_pc
);
5293 if (s
&& s
->language
!= language_asm
)
5294 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5295 ecs
->stop_func_start
);
5297 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5298 /* Use the step_resume_break to step until the end of the prologue,
5299 even if that involves jumps (as it seems to on the vax under
5301 /* If the prologue ends in the middle of a source line, continue to
5302 the end of that source line (if it is still within the function).
5303 Otherwise, just go to end of prologue. */
5304 if (stop_func_sal
.end
5305 && stop_func_sal
.pc
!= ecs
->stop_func_start
5306 && stop_func_sal
.end
< ecs
->stop_func_end
)
5307 ecs
->stop_func_start
= stop_func_sal
.end
;
5309 /* Architectures which require breakpoint adjustment might not be able
5310 to place a breakpoint at the computed address. If so, the test
5311 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5312 ecs->stop_func_start to an address at which a breakpoint may be
5313 legitimately placed.
5315 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5316 made, GDB will enter an infinite loop when stepping through
5317 optimized code consisting of VLIW instructions which contain
5318 subinstructions corresponding to different source lines. On
5319 FR-V, it's not permitted to place a breakpoint on any but the
5320 first subinstruction of a VLIW instruction. When a breakpoint is
5321 set, GDB will adjust the breakpoint address to the beginning of
5322 the VLIW instruction. Thus, we need to make the corresponding
5323 adjustment here when computing the stop address. */
5325 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5327 ecs
->stop_func_start
5328 = gdbarch_adjust_breakpoint_address (gdbarch
,
5329 ecs
->stop_func_start
);
5332 if (ecs
->stop_func_start
== stop_pc
)
5334 /* We are already there: stop now. */
5335 ecs
->event_thread
->control
.stop_step
= 1;
5336 print_end_stepping_range_reason ();
5337 stop_stepping (ecs
);
5342 /* Put the step-breakpoint there and go until there. */
5343 init_sal (&sr_sal
); /* initialize to zeroes */
5344 sr_sal
.pc
= ecs
->stop_func_start
;
5345 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5346 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5348 /* Do not specify what the fp should be when we stop since on
5349 some machines the prologue is where the new fp value is
5351 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5353 /* And make sure stepping stops right away then. */
5354 ecs
->event_thread
->control
.step_range_end
5355 = ecs
->event_thread
->control
.step_range_start
;
5360 /* Inferior has stepped backward into a subroutine call with source
5361 code that we should not step over. Do step to the beginning of the
5362 last line of code in it. */
5365 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5366 struct execution_control_state
*ecs
)
5369 struct symtab_and_line stop_func_sal
;
5371 fill_in_stop_func (gdbarch
, ecs
);
5373 s
= find_pc_symtab (stop_pc
);
5374 if (s
&& s
->language
!= language_asm
)
5375 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5376 ecs
->stop_func_start
);
5378 stop_func_sal
= find_pc_line (stop_pc
, 0);
5380 /* OK, we're just going to keep stepping here. */
5381 if (stop_func_sal
.pc
== stop_pc
)
5383 /* We're there already. Just stop stepping now. */
5384 ecs
->event_thread
->control
.stop_step
= 1;
5385 print_end_stepping_range_reason ();
5386 stop_stepping (ecs
);
5390 /* Else just reset the step range and keep going.
5391 No step-resume breakpoint, they don't work for
5392 epilogues, which can have multiple entry paths. */
5393 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5394 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5400 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5401 This is used to both functions and to skip over code. */
5404 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5405 struct symtab_and_line sr_sal
,
5406 struct frame_id sr_id
,
5407 enum bptype sr_type
)
5409 /* There should never be more than one step-resume or longjmp-resume
5410 breakpoint per thread, so we should never be setting a new
5411 step_resume_breakpoint when one is already active. */
5412 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5413 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5416 fprintf_unfiltered (gdb_stdlog
,
5417 "infrun: inserting step-resume breakpoint at %s\n",
5418 paddress (gdbarch
, sr_sal
.pc
));
5420 inferior_thread ()->control
.step_resume_breakpoint
5421 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5425 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5426 struct symtab_and_line sr_sal
,
5427 struct frame_id sr_id
)
5429 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5434 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5435 This is used to skip a potential signal handler.
5437 This is called with the interrupted function's frame. The signal
5438 handler, when it returns, will resume the interrupted function at
5442 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5444 struct symtab_and_line sr_sal
;
5445 struct gdbarch
*gdbarch
;
5447 gdb_assert (return_frame
!= NULL
);
5448 init_sal (&sr_sal
); /* initialize to zeros */
5450 gdbarch
= get_frame_arch (return_frame
);
5451 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5452 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5453 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5455 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5456 get_stack_frame_id (return_frame
),
5460 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5461 is used to skip a function after stepping into it (for "next" or if
5462 the called function has no debugging information).
5464 The current function has almost always been reached by single
5465 stepping a call or return instruction. NEXT_FRAME belongs to the
5466 current function, and the breakpoint will be set at the caller's
5469 This is a separate function rather than reusing
5470 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5471 get_prev_frame, which may stop prematurely (see the implementation
5472 of frame_unwind_caller_id for an example). */
5475 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5477 struct symtab_and_line sr_sal
;
5478 struct gdbarch
*gdbarch
;
5480 /* We shouldn't have gotten here if we don't know where the call site
5482 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5484 init_sal (&sr_sal
); /* initialize to zeros */
5486 gdbarch
= frame_unwind_caller_arch (next_frame
);
5487 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5488 frame_unwind_caller_pc (next_frame
));
5489 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5490 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5492 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5493 frame_unwind_caller_id (next_frame
));
5496 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5497 new breakpoint at the target of a jmp_buf. The handling of
5498 longjmp-resume uses the same mechanisms used for handling
5499 "step-resume" breakpoints. */
5502 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5504 /* There should never be more than one longjmp-resume breakpoint per
5505 thread, so we should never be setting a new
5506 longjmp_resume_breakpoint when one is already active. */
5507 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
5510 fprintf_unfiltered (gdb_stdlog
,
5511 "infrun: inserting longjmp-resume breakpoint at %s\n",
5512 paddress (gdbarch
, pc
));
5514 inferior_thread ()->control
.exception_resume_breakpoint
=
5515 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5518 /* Insert an exception resume breakpoint. TP is the thread throwing
5519 the exception. The block B is the block of the unwinder debug hook
5520 function. FRAME is the frame corresponding to the call to this
5521 function. SYM is the symbol of the function argument holding the
5522 target PC of the exception. */
5525 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5527 struct frame_info
*frame
,
5530 volatile struct gdb_exception e
;
5532 /* We want to ignore errors here. */
5533 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5535 struct symbol
*vsym
;
5536 struct value
*value
;
5538 struct breakpoint
*bp
;
5540 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5541 value
= read_var_value (vsym
, frame
);
5542 /* If the value was optimized out, revert to the old behavior. */
5543 if (! value_optimized_out (value
))
5545 handler
= value_as_address (value
);
5548 fprintf_unfiltered (gdb_stdlog
,
5549 "infrun: exception resume at %lx\n",
5550 (unsigned long) handler
);
5552 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5553 handler
, bp_exception_resume
);
5555 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5558 bp
->thread
= tp
->num
;
5559 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5564 /* A helper for check_exception_resume that sets an
5565 exception-breakpoint based on a SystemTap probe. */
5568 insert_exception_resume_from_probe (struct thread_info
*tp
,
5569 const struct probe
*probe
,
5570 struct frame_info
*frame
)
5572 struct value
*arg_value
;
5574 struct breakpoint
*bp
;
5576 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
5580 handler
= value_as_address (arg_value
);
5583 fprintf_unfiltered (gdb_stdlog
,
5584 "infrun: exception resume at %s\n",
5585 paddress (get_objfile_arch (probe
->objfile
),
5588 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5589 handler
, bp_exception_resume
);
5590 bp
->thread
= tp
->num
;
5591 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5594 /* This is called when an exception has been intercepted. Check to
5595 see whether the exception's destination is of interest, and if so,
5596 set an exception resume breakpoint there. */
5599 check_exception_resume (struct execution_control_state
*ecs
,
5600 struct frame_info
*frame
)
5602 volatile struct gdb_exception e
;
5603 const struct probe
*probe
;
5604 struct symbol
*func
;
5606 /* First see if this exception unwinding breakpoint was set via a
5607 SystemTap probe point. If so, the probe has two arguments: the
5608 CFA and the HANDLER. We ignore the CFA, extract the handler, and
5609 set a breakpoint there. */
5610 probe
= find_probe_by_pc (get_frame_pc (frame
));
5613 insert_exception_resume_from_probe (ecs
->event_thread
, probe
, frame
);
5617 func
= get_frame_function (frame
);
5621 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5624 struct block_iterator iter
;
5628 /* The exception breakpoint is a thread-specific breakpoint on
5629 the unwinder's debug hook, declared as:
5631 void _Unwind_DebugHook (void *cfa, void *handler);
5633 The CFA argument indicates the frame to which control is
5634 about to be transferred. HANDLER is the destination PC.
5636 We ignore the CFA and set a temporary breakpoint at HANDLER.
5637 This is not extremely efficient but it avoids issues in gdb
5638 with computing the DWARF CFA, and it also works even in weird
5639 cases such as throwing an exception from inside a signal
5642 b
= SYMBOL_BLOCK_VALUE (func
);
5643 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
5645 if (!SYMBOL_IS_ARGUMENT (sym
))
5652 insert_exception_resume_breakpoint (ecs
->event_thread
,
5661 stop_stepping (struct execution_control_state
*ecs
)
5664 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
5666 /* Let callers know we don't want to wait for the inferior anymore. */
5667 ecs
->wait_some_more
= 0;
5670 /* This function handles various cases where we need to continue
5671 waiting for the inferior. */
5672 /* (Used to be the keep_going: label in the old wait_for_inferior). */
5675 keep_going (struct execution_control_state
*ecs
)
5677 /* Make sure normal_stop is called if we get a QUIT handled before
5679 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
5681 /* Save the pc before execution, to compare with pc after stop. */
5682 ecs
->event_thread
->prev_pc
5683 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5685 /* If we did not do break;, it means we should keep running the
5686 inferior and not return to debugger. */
5688 if (ecs
->event_thread
->control
.trap_expected
5689 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5691 /* We took a signal (which we are supposed to pass through to
5692 the inferior, else we'd not get here) and we haven't yet
5693 gotten our trap. Simply continue. */
5695 discard_cleanups (old_cleanups
);
5696 resume (currently_stepping (ecs
->event_thread
),
5697 ecs
->event_thread
->suspend
.stop_signal
);
5701 /* Either the trap was not expected, but we are continuing
5702 anyway (the user asked that this signal be passed to the
5705 The signal was SIGTRAP, e.g. it was our signal, but we
5706 decided we should resume from it.
5708 We're going to run this baby now!
5710 Note that insert_breakpoints won't try to re-insert
5711 already inserted breakpoints. Therefore, we don't
5712 care if breakpoints were already inserted, or not. */
5714 if (ecs
->event_thread
->stepping_over_breakpoint
)
5716 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
5718 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
5719 /* Since we can't do a displaced step, we have to remove
5720 the breakpoint while we step it. To keep things
5721 simple, we remove them all. */
5722 remove_breakpoints ();
5726 volatile struct gdb_exception e
;
5728 /* Stop stepping when inserting breakpoints
5730 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5732 insert_breakpoints ();
5736 exception_print (gdb_stderr
, e
);
5737 stop_stepping (ecs
);
5742 ecs
->event_thread
->control
.trap_expected
5743 = ecs
->event_thread
->stepping_over_breakpoint
;
5745 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
5746 specifies that such a signal should be delivered to the
5749 Typically, this would occure when a user is debugging a
5750 target monitor on a simulator: the target monitor sets a
5751 breakpoint; the simulator encounters this break-point and
5752 halts the simulation handing control to GDB; GDB, noteing
5753 that the break-point isn't valid, returns control back to the
5754 simulator; the simulator then delivers the hardware
5755 equivalent of a SIGNAL_TRAP to the program being debugged. */
5757 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5758 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5759 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5761 discard_cleanups (old_cleanups
);
5762 resume (currently_stepping (ecs
->event_thread
),
5763 ecs
->event_thread
->suspend
.stop_signal
);
5766 prepare_to_wait (ecs
);
5769 /* This function normally comes after a resume, before
5770 handle_inferior_event exits. It takes care of any last bits of
5771 housekeeping, and sets the all-important wait_some_more flag. */
5774 prepare_to_wait (struct execution_control_state
*ecs
)
5777 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
5779 /* This is the old end of the while loop. Let everybody know we
5780 want to wait for the inferior some more and get called again
5782 ecs
->wait_some_more
= 1;
5785 /* Several print_*_reason functions to print why the inferior has stopped.
5786 We always print something when the inferior exits, or receives a signal.
5787 The rest of the cases are dealt with later on in normal_stop and
5788 print_it_typical. Ideally there should be a call to one of these
5789 print_*_reason functions functions from handle_inferior_event each time
5790 stop_stepping is called. */
5792 /* Print why the inferior has stopped.
5793 We are done with a step/next/si/ni command, print why the inferior has
5794 stopped. For now print nothing. Print a message only if not in the middle
5795 of doing a "step n" operation for n > 1. */
5798 print_end_stepping_range_reason (void)
5800 if ((!inferior_thread ()->step_multi
5801 || !inferior_thread ()->control
.stop_step
)
5802 && ui_out_is_mi_like_p (current_uiout
))
5803 ui_out_field_string (current_uiout
, "reason",
5804 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
5807 /* The inferior was terminated by a signal, print why it stopped. */
5810 print_signal_exited_reason (enum gdb_signal siggnal
)
5812 struct ui_out
*uiout
= current_uiout
;
5814 annotate_signalled ();
5815 if (ui_out_is_mi_like_p (uiout
))
5817 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
5818 ui_out_text (uiout
, "\nProgram terminated with signal ");
5819 annotate_signal_name ();
5820 ui_out_field_string (uiout
, "signal-name",
5821 gdb_signal_to_name (siggnal
));
5822 annotate_signal_name_end ();
5823 ui_out_text (uiout
, ", ");
5824 annotate_signal_string ();
5825 ui_out_field_string (uiout
, "signal-meaning",
5826 gdb_signal_to_string (siggnal
));
5827 annotate_signal_string_end ();
5828 ui_out_text (uiout
, ".\n");
5829 ui_out_text (uiout
, "The program no longer exists.\n");
5832 /* The inferior program is finished, print why it stopped. */
5835 print_exited_reason (int exitstatus
)
5837 struct inferior
*inf
= current_inferior ();
5838 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
5839 struct ui_out
*uiout
= current_uiout
;
5841 annotate_exited (exitstatus
);
5844 if (ui_out_is_mi_like_p (uiout
))
5845 ui_out_field_string (uiout
, "reason",
5846 async_reason_lookup (EXEC_ASYNC_EXITED
));
5847 ui_out_text (uiout
, "[Inferior ");
5848 ui_out_text (uiout
, plongest (inf
->num
));
5849 ui_out_text (uiout
, " (");
5850 ui_out_text (uiout
, pidstr
);
5851 ui_out_text (uiout
, ") exited with code ");
5852 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
5853 ui_out_text (uiout
, "]\n");
5857 if (ui_out_is_mi_like_p (uiout
))
5859 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
5860 ui_out_text (uiout
, "[Inferior ");
5861 ui_out_text (uiout
, plongest (inf
->num
));
5862 ui_out_text (uiout
, " (");
5863 ui_out_text (uiout
, pidstr
);
5864 ui_out_text (uiout
, ") exited normally]\n");
5866 /* Support the --return-child-result option. */
5867 return_child_result_value
= exitstatus
;
5870 /* Signal received, print why the inferior has stopped. The signal table
5871 tells us to print about it. */
5874 print_signal_received_reason (enum gdb_signal siggnal
)
5876 struct ui_out
*uiout
= current_uiout
;
5880 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
5882 struct thread_info
*t
= inferior_thread ();
5884 ui_out_text (uiout
, "\n[");
5885 ui_out_field_string (uiout
, "thread-name",
5886 target_pid_to_str (t
->ptid
));
5887 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
5888 ui_out_text (uiout
, " stopped");
5892 ui_out_text (uiout
, "\nProgram received signal ");
5893 annotate_signal_name ();
5894 if (ui_out_is_mi_like_p (uiout
))
5896 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
5897 ui_out_field_string (uiout
, "signal-name",
5898 gdb_signal_to_name (siggnal
));
5899 annotate_signal_name_end ();
5900 ui_out_text (uiout
, ", ");
5901 annotate_signal_string ();
5902 ui_out_field_string (uiout
, "signal-meaning",
5903 gdb_signal_to_string (siggnal
));
5904 annotate_signal_string_end ();
5906 ui_out_text (uiout
, ".\n");
5909 /* Reverse execution: target ran out of history info, print why the inferior
5913 print_no_history_reason (void)
5915 ui_out_text (current_uiout
, "\nNo more reverse-execution history.\n");
5918 /* Here to return control to GDB when the inferior stops for real.
5919 Print appropriate messages, remove breakpoints, give terminal our modes.
5921 STOP_PRINT_FRAME nonzero means print the executing frame
5922 (pc, function, args, file, line number and line text).
5923 BREAKPOINTS_FAILED nonzero means stop was due to error
5924 attempting to insert breakpoints. */
5929 struct target_waitstatus last
;
5931 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
5933 get_last_target_status (&last_ptid
, &last
);
5935 /* If an exception is thrown from this point on, make sure to
5936 propagate GDB's knowledge of the executing state to the
5937 frontend/user running state. A QUIT is an easy exception to see
5938 here, so do this before any filtered output. */
5940 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
5941 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
5942 && last
.kind
!= TARGET_WAITKIND_EXITED
5943 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
5944 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
5946 /* In non-stop mode, we don't want GDB to switch threads behind the
5947 user's back, to avoid races where the user is typing a command to
5948 apply to thread x, but GDB switches to thread y before the user
5949 finishes entering the command. */
5951 /* As with the notification of thread events, we want to delay
5952 notifying the user that we've switched thread context until
5953 the inferior actually stops.
5955 There's no point in saying anything if the inferior has exited.
5956 Note that SIGNALLED here means "exited with a signal", not
5957 "received a signal". */
5959 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
5960 && target_has_execution
5961 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5962 && last
.kind
!= TARGET_WAITKIND_EXITED
5963 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
5965 target_terminal_ours_for_output ();
5966 printf_filtered (_("[Switching to %s]\n"),
5967 target_pid_to_str (inferior_ptid
));
5968 annotate_thread_changed ();
5969 previous_inferior_ptid
= inferior_ptid
;
5972 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
5974 gdb_assert (sync_execution
|| !target_can_async_p ());
5976 target_terminal_ours_for_output ();
5977 printf_filtered (_("No unwaited-for children left.\n"));
5980 if (!breakpoints_always_inserted_mode () && target_has_execution
)
5982 if (remove_breakpoints ())
5984 target_terminal_ours_for_output ();
5985 printf_filtered (_("Cannot remove breakpoints because "
5986 "program is no longer writable.\nFurther "
5987 "execution is probably impossible.\n"));
5991 /* If an auto-display called a function and that got a signal,
5992 delete that auto-display to avoid an infinite recursion. */
5994 if (stopped_by_random_signal
)
5995 disable_current_display ();
5997 /* Don't print a message if in the middle of doing a "step n"
5998 operation for n > 1 */
5999 if (target_has_execution
6000 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6001 && last
.kind
!= TARGET_WAITKIND_EXITED
6002 && inferior_thread ()->step_multi
6003 && inferior_thread ()->control
.stop_step
)
6006 target_terminal_ours ();
6007 async_enable_stdin ();
6009 /* Set the current source location. This will also happen if we
6010 display the frame below, but the current SAL will be incorrect
6011 during a user hook-stop function. */
6012 if (has_stack_frames () && !stop_stack_dummy
)
6013 set_current_sal_from_frame (get_current_frame (), 1);
6015 /* Let the user/frontend see the threads as stopped. */
6016 do_cleanups (old_chain
);
6018 /* Look up the hook_stop and run it (CLI internally handles problem
6019 of stop_command's pre-hook not existing). */
6021 catch_errors (hook_stop_stub
, stop_command
,
6022 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
6024 if (!has_stack_frames ())
6027 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
6028 || last
.kind
== TARGET_WAITKIND_EXITED
)
6031 /* Select innermost stack frame - i.e., current frame is frame 0,
6032 and current location is based on that.
6033 Don't do this on return from a stack dummy routine,
6034 or if the program has exited. */
6036 if (!stop_stack_dummy
)
6038 select_frame (get_current_frame ());
6040 /* Print current location without a level number, if
6041 we have changed functions or hit a breakpoint.
6042 Print source line if we have one.
6043 bpstat_print() contains the logic deciding in detail
6044 what to print, based on the event(s) that just occurred. */
6046 /* If --batch-silent is enabled then there's no need to print the current
6047 source location, and to try risks causing an error message about
6048 missing source files. */
6049 if (stop_print_frame
&& !batch_silent
)
6053 int do_frame_printing
= 1;
6054 struct thread_info
*tp
= inferior_thread ();
6056 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, last
.kind
);
6060 /* FIXME: cagney/2002-12-01: Given that a frame ID does
6061 (or should) carry around the function and does (or
6062 should) use that when doing a frame comparison. */
6063 if (tp
->control
.stop_step
6064 && frame_id_eq (tp
->control
.step_frame_id
,
6065 get_frame_id (get_current_frame ()))
6066 && step_start_function
== find_pc_function (stop_pc
))
6067 source_flag
= SRC_LINE
; /* Finished step, just
6068 print source line. */
6070 source_flag
= SRC_AND_LOC
; /* Print location and
6073 case PRINT_SRC_AND_LOC
:
6074 source_flag
= SRC_AND_LOC
; /* Print location and
6077 case PRINT_SRC_ONLY
:
6078 source_flag
= SRC_LINE
;
6081 source_flag
= SRC_LINE
; /* something bogus */
6082 do_frame_printing
= 0;
6085 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6088 /* The behavior of this routine with respect to the source
6090 SRC_LINE: Print only source line
6091 LOCATION: Print only location
6092 SRC_AND_LOC: Print location and source line. */
6093 if (do_frame_printing
)
6094 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
6096 /* Display the auto-display expressions. */
6101 /* Save the function value return registers, if we care.
6102 We might be about to restore their previous contents. */
6103 if (inferior_thread ()->control
.proceed_to_finish
6104 && execution_direction
!= EXEC_REVERSE
)
6106 /* This should not be necessary. */
6108 regcache_xfree (stop_registers
);
6110 /* NB: The copy goes through to the target picking up the value of
6111 all the registers. */
6112 stop_registers
= regcache_dup (get_current_regcache ());
6115 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6117 /* Pop the empty frame that contains the stack dummy.
6118 This also restores inferior state prior to the call
6119 (struct infcall_suspend_state). */
6120 struct frame_info
*frame
= get_current_frame ();
6122 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6124 /* frame_pop() calls reinit_frame_cache as the last thing it
6125 does which means there's currently no selected frame. We
6126 don't need to re-establish a selected frame if the dummy call
6127 returns normally, that will be done by
6128 restore_infcall_control_state. However, we do have to handle
6129 the case where the dummy call is returning after being
6130 stopped (e.g. the dummy call previously hit a breakpoint).
6131 We can't know which case we have so just always re-establish
6132 a selected frame here. */
6133 select_frame (get_current_frame ());
6137 annotate_stopped ();
6139 /* Suppress the stop observer if we're in the middle of:
6141 - a step n (n > 1), as there still more steps to be done.
6143 - a "finish" command, as the observer will be called in
6144 finish_command_continuation, so it can include the inferior
6145 function's return value.
6147 - calling an inferior function, as we pretend we inferior didn't
6148 run at all. The return value of the call is handled by the
6149 expression evaluator, through call_function_by_hand. */
6151 if (!target_has_execution
6152 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6153 || last
.kind
== TARGET_WAITKIND_EXITED
6154 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6155 || (!(inferior_thread ()->step_multi
6156 && inferior_thread ()->control
.stop_step
)
6157 && !(inferior_thread ()->control
.stop_bpstat
6158 && inferior_thread ()->control
.proceed_to_finish
)
6159 && !inferior_thread ()->control
.in_infcall
))
6161 if (!ptid_equal (inferior_ptid
, null_ptid
))
6162 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6165 observer_notify_normal_stop (NULL
, stop_print_frame
);
6168 if (target_has_execution
)
6170 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6171 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6172 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6173 Delete any breakpoint that is to be deleted at the next stop. */
6174 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6177 /* Try to get rid of automatically added inferiors that are no
6178 longer needed. Keeping those around slows down things linearly.
6179 Note that this never removes the current inferior. */
6184 hook_stop_stub (void *cmd
)
6186 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6191 signal_stop_state (int signo
)
6193 return signal_stop
[signo
];
6197 signal_print_state (int signo
)
6199 return signal_print
[signo
];
6203 signal_pass_state (int signo
)
6205 return signal_program
[signo
];
6209 signal_cache_update (int signo
)
6213 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6214 signal_cache_update (signo
);
6219 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6220 && signal_print
[signo
] == 0
6221 && signal_program
[signo
] == 1);
6225 signal_stop_update (int signo
, int state
)
6227 int ret
= signal_stop
[signo
];
6229 signal_stop
[signo
] = state
;
6230 signal_cache_update (signo
);
6235 signal_print_update (int signo
, int state
)
6237 int ret
= signal_print
[signo
];
6239 signal_print
[signo
] = state
;
6240 signal_cache_update (signo
);
6245 signal_pass_update (int signo
, int state
)
6247 int ret
= signal_program
[signo
];
6249 signal_program
[signo
] = state
;
6250 signal_cache_update (signo
);
6255 sig_print_header (void)
6257 printf_filtered (_("Signal Stop\tPrint\tPass "
6258 "to program\tDescription\n"));
6262 sig_print_info (enum gdb_signal oursig
)
6264 const char *name
= gdb_signal_to_name (oursig
);
6265 int name_padding
= 13 - strlen (name
);
6267 if (name_padding
<= 0)
6270 printf_filtered ("%s", name
);
6271 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6272 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6273 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6274 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6275 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6278 /* Specify how various signals in the inferior should be handled. */
6281 handle_command (char *args
, int from_tty
)
6284 int digits
, wordlen
;
6285 int sigfirst
, signum
, siglast
;
6286 enum gdb_signal oursig
;
6289 unsigned char *sigs
;
6290 struct cleanup
*old_chain
;
6294 error_no_arg (_("signal to handle"));
6297 /* Allocate and zero an array of flags for which signals to handle. */
6299 nsigs
= (int) GDB_SIGNAL_LAST
;
6300 sigs
= (unsigned char *) alloca (nsigs
);
6301 memset (sigs
, 0, nsigs
);
6303 /* Break the command line up into args. */
6305 argv
= gdb_buildargv (args
);
6306 old_chain
= make_cleanup_freeargv (argv
);
6308 /* Walk through the args, looking for signal oursigs, signal names, and
6309 actions. Signal numbers and signal names may be interspersed with
6310 actions, with the actions being performed for all signals cumulatively
6311 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6313 while (*argv
!= NULL
)
6315 wordlen
= strlen (*argv
);
6316 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6320 sigfirst
= siglast
= -1;
6322 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6324 /* Apply action to all signals except those used by the
6325 debugger. Silently skip those. */
6328 siglast
= nsigs
- 1;
6330 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6332 SET_SIGS (nsigs
, sigs
, signal_stop
);
6333 SET_SIGS (nsigs
, sigs
, signal_print
);
6335 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6337 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6339 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6341 SET_SIGS (nsigs
, sigs
, signal_print
);
6343 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6345 SET_SIGS (nsigs
, sigs
, signal_program
);
6347 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6349 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6351 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6353 SET_SIGS (nsigs
, sigs
, signal_program
);
6355 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6357 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6358 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6360 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6362 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6364 else if (digits
> 0)
6366 /* It is numeric. The numeric signal refers to our own
6367 internal signal numbering from target.h, not to host/target
6368 signal number. This is a feature; users really should be
6369 using symbolic names anyway, and the common ones like
6370 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6372 sigfirst
= siglast
= (int)
6373 gdb_signal_from_command (atoi (*argv
));
6374 if ((*argv
)[digits
] == '-')
6377 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6379 if (sigfirst
> siglast
)
6381 /* Bet he didn't figure we'd think of this case... */
6389 oursig
= gdb_signal_from_name (*argv
);
6390 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
6392 sigfirst
= siglast
= (int) oursig
;
6396 /* Not a number and not a recognized flag word => complain. */
6397 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6401 /* If any signal numbers or symbol names were found, set flags for
6402 which signals to apply actions to. */
6404 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6406 switch ((enum gdb_signal
) signum
)
6408 case GDB_SIGNAL_TRAP
:
6409 case GDB_SIGNAL_INT
:
6410 if (!allsigs
&& !sigs
[signum
])
6412 if (query (_("%s is used by the debugger.\n\
6413 Are you sure you want to change it? "),
6414 gdb_signal_to_name ((enum gdb_signal
) signum
)))
6420 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6421 gdb_flush (gdb_stdout
);
6426 case GDB_SIGNAL_DEFAULT
:
6427 case GDB_SIGNAL_UNKNOWN
:
6428 /* Make sure that "all" doesn't print these. */
6439 for (signum
= 0; signum
< nsigs
; signum
++)
6442 signal_cache_update (-1);
6443 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6444 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
6448 /* Show the results. */
6449 sig_print_header ();
6450 for (; signum
< nsigs
; signum
++)
6452 sig_print_info (signum
);
6458 do_cleanups (old_chain
);
6461 /* Complete the "handle" command. */
6463 static VEC (char_ptr
) *
6464 handle_completer (struct cmd_list_element
*ignore
,
6465 char *text
, char *word
)
6467 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
6468 static const char * const keywords
[] =
6482 vec_signals
= signal_completer (ignore
, text
, word
);
6483 vec_keywords
= complete_on_enum (keywords
, word
, word
);
6485 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
6486 VEC_free (char_ptr
, vec_signals
);
6487 VEC_free (char_ptr
, vec_keywords
);
6492 xdb_handle_command (char *args
, int from_tty
)
6495 struct cleanup
*old_chain
;
6498 error_no_arg (_("xdb command"));
6500 /* Break the command line up into args. */
6502 argv
= gdb_buildargv (args
);
6503 old_chain
= make_cleanup_freeargv (argv
);
6504 if (argv
[1] != (char *) NULL
)
6509 bufLen
= strlen (argv
[0]) + 20;
6510 argBuf
= (char *) xmalloc (bufLen
);
6514 enum gdb_signal oursig
;
6516 oursig
= gdb_signal_from_name (argv
[0]);
6517 memset (argBuf
, 0, bufLen
);
6518 if (strcmp (argv
[1], "Q") == 0)
6519 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6522 if (strcmp (argv
[1], "s") == 0)
6524 if (!signal_stop
[oursig
])
6525 sprintf (argBuf
, "%s %s", argv
[0], "stop");
6527 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
6529 else if (strcmp (argv
[1], "i") == 0)
6531 if (!signal_program
[oursig
])
6532 sprintf (argBuf
, "%s %s", argv
[0], "pass");
6534 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
6536 else if (strcmp (argv
[1], "r") == 0)
6538 if (!signal_print
[oursig
])
6539 sprintf (argBuf
, "%s %s", argv
[0], "print");
6541 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6547 handle_command (argBuf
, from_tty
);
6549 printf_filtered (_("Invalid signal handling flag.\n"));
6554 do_cleanups (old_chain
);
6558 gdb_signal_from_command (int num
)
6560 if (num
>= 1 && num
<= 15)
6561 return (enum gdb_signal
) num
;
6562 error (_("Only signals 1-15 are valid as numeric signals.\n\
6563 Use \"info signals\" for a list of symbolic signals."));
6566 /* Print current contents of the tables set by the handle command.
6567 It is possible we should just be printing signals actually used
6568 by the current target (but for things to work right when switching
6569 targets, all signals should be in the signal tables). */
6572 signals_info (char *signum_exp
, int from_tty
)
6574 enum gdb_signal oursig
;
6576 sig_print_header ();
6580 /* First see if this is a symbol name. */
6581 oursig
= gdb_signal_from_name (signum_exp
);
6582 if (oursig
== GDB_SIGNAL_UNKNOWN
)
6584 /* No, try numeric. */
6586 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
6588 sig_print_info (oursig
);
6592 printf_filtered ("\n");
6593 /* These ugly casts brought to you by the native VAX compiler. */
6594 for (oursig
= GDB_SIGNAL_FIRST
;
6595 (int) oursig
< (int) GDB_SIGNAL_LAST
;
6596 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
6600 if (oursig
!= GDB_SIGNAL_UNKNOWN
6601 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
6602 sig_print_info (oursig
);
6605 printf_filtered (_("\nUse the \"handle\" command "
6606 "to change these tables.\n"));
6609 /* Check if it makes sense to read $_siginfo from the current thread
6610 at this point. If not, throw an error. */
6613 validate_siginfo_access (void)
6615 /* No current inferior, no siginfo. */
6616 if (ptid_equal (inferior_ptid
, null_ptid
))
6617 error (_("No thread selected."));
6619 /* Don't try to read from a dead thread. */
6620 if (is_exited (inferior_ptid
))
6621 error (_("The current thread has terminated"));
6623 /* ... or from a spinning thread. */
6624 if (is_running (inferior_ptid
))
6625 error (_("Selected thread is running."));
6628 /* The $_siginfo convenience variable is a bit special. We don't know
6629 for sure the type of the value until we actually have a chance to
6630 fetch the data. The type can change depending on gdbarch, so it is
6631 also dependent on which thread you have selected.
6633 1. making $_siginfo be an internalvar that creates a new value on
6636 2. making the value of $_siginfo be an lval_computed value. */
6638 /* This function implements the lval_computed support for reading a
6642 siginfo_value_read (struct value
*v
)
6644 LONGEST transferred
;
6646 validate_siginfo_access ();
6649 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
6651 value_contents_all_raw (v
),
6653 TYPE_LENGTH (value_type (v
)));
6655 if (transferred
!= TYPE_LENGTH (value_type (v
)))
6656 error (_("Unable to read siginfo"));
6659 /* This function implements the lval_computed support for writing a
6663 siginfo_value_write (struct value
*v
, struct value
*fromval
)
6665 LONGEST transferred
;
6667 validate_siginfo_access ();
6669 transferred
= target_write (¤t_target
,
6670 TARGET_OBJECT_SIGNAL_INFO
,
6672 value_contents_all_raw (fromval
),
6674 TYPE_LENGTH (value_type (fromval
)));
6676 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
6677 error (_("Unable to write siginfo"));
6680 static const struct lval_funcs siginfo_value_funcs
=
6686 /* Return a new value with the correct type for the siginfo object of
6687 the current thread using architecture GDBARCH. Return a void value
6688 if there's no object available. */
6690 static struct value
*
6691 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
6694 if (target_has_stack
6695 && !ptid_equal (inferior_ptid
, null_ptid
)
6696 && gdbarch_get_siginfo_type_p (gdbarch
))
6698 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6700 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
6703 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
6707 /* infcall_suspend_state contains state about the program itself like its
6708 registers and any signal it received when it last stopped.
6709 This state must be restored regardless of how the inferior function call
6710 ends (either successfully, or after it hits a breakpoint or signal)
6711 if the program is to properly continue where it left off. */
6713 struct infcall_suspend_state
6715 struct thread_suspend_state thread_suspend
;
6716 #if 0 /* Currently unused and empty structures are not valid C. */
6717 struct inferior_suspend_state inferior_suspend
;
6722 struct regcache
*registers
;
6724 /* Format of SIGINFO_DATA or NULL if it is not present. */
6725 struct gdbarch
*siginfo_gdbarch
;
6727 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
6728 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
6729 content would be invalid. */
6730 gdb_byte
*siginfo_data
;
6733 struct infcall_suspend_state
*
6734 save_infcall_suspend_state (void)
6736 struct infcall_suspend_state
*inf_state
;
6737 struct thread_info
*tp
= inferior_thread ();
6738 struct inferior
*inf
= current_inferior ();
6739 struct regcache
*regcache
= get_current_regcache ();
6740 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6741 gdb_byte
*siginfo_data
= NULL
;
6743 if (gdbarch_get_siginfo_type_p (gdbarch
))
6745 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6746 size_t len
= TYPE_LENGTH (type
);
6747 struct cleanup
*back_to
;
6749 siginfo_data
= xmalloc (len
);
6750 back_to
= make_cleanup (xfree
, siginfo_data
);
6752 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6753 siginfo_data
, 0, len
) == len
)
6754 discard_cleanups (back_to
);
6757 /* Errors ignored. */
6758 do_cleanups (back_to
);
6759 siginfo_data
= NULL
;
6763 inf_state
= XZALLOC (struct infcall_suspend_state
);
6767 inf_state
->siginfo_gdbarch
= gdbarch
;
6768 inf_state
->siginfo_data
= siginfo_data
;
6771 inf_state
->thread_suspend
= tp
->suspend
;
6772 #if 0 /* Currently unused and empty structures are not valid C. */
6773 inf_state
->inferior_suspend
= inf
->suspend
;
6776 /* run_inferior_call will not use the signal due to its `proceed' call with
6777 GDB_SIGNAL_0 anyway. */
6778 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6780 inf_state
->stop_pc
= stop_pc
;
6782 inf_state
->registers
= regcache_dup (regcache
);
6787 /* Restore inferior session state to INF_STATE. */
6790 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6792 struct thread_info
*tp
= inferior_thread ();
6793 struct inferior
*inf
= current_inferior ();
6794 struct regcache
*regcache
= get_current_regcache ();
6795 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6797 tp
->suspend
= inf_state
->thread_suspend
;
6798 #if 0 /* Currently unused and empty structures are not valid C. */
6799 inf
->suspend
= inf_state
->inferior_suspend
;
6802 stop_pc
= inf_state
->stop_pc
;
6804 if (inf_state
->siginfo_gdbarch
== gdbarch
)
6806 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6808 /* Errors ignored. */
6809 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6810 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
6813 /* The inferior can be gone if the user types "print exit(0)"
6814 (and perhaps other times). */
6815 if (target_has_execution
)
6816 /* NB: The register write goes through to the target. */
6817 regcache_cpy (regcache
, inf_state
->registers
);
6819 discard_infcall_suspend_state (inf_state
);
6823 do_restore_infcall_suspend_state_cleanup (void *state
)
6825 restore_infcall_suspend_state (state
);
6829 make_cleanup_restore_infcall_suspend_state
6830 (struct infcall_suspend_state
*inf_state
)
6832 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
6836 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6838 regcache_xfree (inf_state
->registers
);
6839 xfree (inf_state
->siginfo_data
);
6844 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
6846 return inf_state
->registers
;
6849 /* infcall_control_state contains state regarding gdb's control of the
6850 inferior itself like stepping control. It also contains session state like
6851 the user's currently selected frame. */
6853 struct infcall_control_state
6855 struct thread_control_state thread_control
;
6856 struct inferior_control_state inferior_control
;
6859 enum stop_stack_kind stop_stack_dummy
;
6860 int stopped_by_random_signal
;
6861 int stop_after_trap
;
6863 /* ID if the selected frame when the inferior function call was made. */
6864 struct frame_id selected_frame_id
;
6867 /* Save all of the information associated with the inferior<==>gdb
6870 struct infcall_control_state
*
6871 save_infcall_control_state (void)
6873 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
6874 struct thread_info
*tp
= inferior_thread ();
6875 struct inferior
*inf
= current_inferior ();
6877 inf_status
->thread_control
= tp
->control
;
6878 inf_status
->inferior_control
= inf
->control
;
6880 tp
->control
.step_resume_breakpoint
= NULL
;
6881 tp
->control
.exception_resume_breakpoint
= NULL
;
6883 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
6884 chain. If caller's caller is walking the chain, they'll be happier if we
6885 hand them back the original chain when restore_infcall_control_state is
6887 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
6890 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
6891 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
6892 inf_status
->stop_after_trap
= stop_after_trap
;
6894 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
6900 restore_selected_frame (void *args
)
6902 struct frame_id
*fid
= (struct frame_id
*) args
;
6903 struct frame_info
*frame
;
6905 frame
= frame_find_by_id (*fid
);
6907 /* If inf_status->selected_frame_id is NULL, there was no previously
6911 warning (_("Unable to restore previously selected frame."));
6915 select_frame (frame
);
6920 /* Restore inferior session state to INF_STATUS. */
6923 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
6925 struct thread_info
*tp
= inferior_thread ();
6926 struct inferior
*inf
= current_inferior ();
6928 if (tp
->control
.step_resume_breakpoint
)
6929 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
6931 if (tp
->control
.exception_resume_breakpoint
)
6932 tp
->control
.exception_resume_breakpoint
->disposition
6933 = disp_del_at_next_stop
;
6935 /* Handle the bpstat_copy of the chain. */
6936 bpstat_clear (&tp
->control
.stop_bpstat
);
6938 tp
->control
= inf_status
->thread_control
;
6939 inf
->control
= inf_status
->inferior_control
;
6942 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
6943 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
6944 stop_after_trap
= inf_status
->stop_after_trap
;
6946 if (target_has_stack
)
6948 /* The point of catch_errors is that if the stack is clobbered,
6949 walking the stack might encounter a garbage pointer and
6950 error() trying to dereference it. */
6952 (restore_selected_frame
, &inf_status
->selected_frame_id
,
6953 "Unable to restore previously selected frame:\n",
6954 RETURN_MASK_ERROR
) == 0)
6955 /* Error in restoring the selected frame. Select the innermost
6957 select_frame (get_current_frame ());
6964 do_restore_infcall_control_state_cleanup (void *sts
)
6966 restore_infcall_control_state (sts
);
6970 make_cleanup_restore_infcall_control_state
6971 (struct infcall_control_state
*inf_status
)
6973 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
6977 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
6979 if (inf_status
->thread_control
.step_resume_breakpoint
)
6980 inf_status
->thread_control
.step_resume_breakpoint
->disposition
6981 = disp_del_at_next_stop
;
6983 if (inf_status
->thread_control
.exception_resume_breakpoint
)
6984 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
6985 = disp_del_at_next_stop
;
6987 /* See save_infcall_control_state for info on stop_bpstat. */
6988 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
6994 ptid_match (ptid_t ptid
, ptid_t filter
)
6996 if (ptid_equal (filter
, minus_one_ptid
))
6998 if (ptid_is_pid (filter
)
6999 && ptid_get_pid (ptid
) == ptid_get_pid (filter
))
7001 else if (ptid_equal (ptid
, filter
))
7007 /* restore_inferior_ptid() will be used by the cleanup machinery
7008 to restore the inferior_ptid value saved in a call to
7009 save_inferior_ptid(). */
7012 restore_inferior_ptid (void *arg
)
7014 ptid_t
*saved_ptid_ptr
= arg
;
7016 inferior_ptid
= *saved_ptid_ptr
;
7020 /* Save the value of inferior_ptid so that it may be restored by a
7021 later call to do_cleanups(). Returns the struct cleanup pointer
7022 needed for later doing the cleanup. */
7025 save_inferior_ptid (void)
7027 ptid_t
*saved_ptid_ptr
;
7029 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
7030 *saved_ptid_ptr
= inferior_ptid
;
7031 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
7035 /* User interface for reverse debugging:
7036 Set exec-direction / show exec-direction commands
7037 (returns error unless target implements to_set_exec_direction method). */
7039 int execution_direction
= EXEC_FORWARD
;
7040 static const char exec_forward
[] = "forward";
7041 static const char exec_reverse
[] = "reverse";
7042 static const char *exec_direction
= exec_forward
;
7043 static const char *const exec_direction_names
[] = {
7050 set_exec_direction_func (char *args
, int from_tty
,
7051 struct cmd_list_element
*cmd
)
7053 if (target_can_execute_reverse
)
7055 if (!strcmp (exec_direction
, exec_forward
))
7056 execution_direction
= EXEC_FORWARD
;
7057 else if (!strcmp (exec_direction
, exec_reverse
))
7058 execution_direction
= EXEC_REVERSE
;
7062 exec_direction
= exec_forward
;
7063 error (_("Target does not support this operation."));
7068 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7069 struct cmd_list_element
*cmd
, const char *value
)
7071 switch (execution_direction
) {
7073 fprintf_filtered (out
, _("Forward.\n"));
7076 fprintf_filtered (out
, _("Reverse.\n"));
7079 internal_error (__FILE__
, __LINE__
,
7080 _("bogus execution_direction value: %d"),
7081 (int) execution_direction
);
7085 /* User interface for non-stop mode. */
7090 set_non_stop (char *args
, int from_tty
,
7091 struct cmd_list_element
*c
)
7093 if (target_has_execution
)
7095 non_stop_1
= non_stop
;
7096 error (_("Cannot change this setting while the inferior is running."));
7099 non_stop
= non_stop_1
;
7103 show_non_stop (struct ui_file
*file
, int from_tty
,
7104 struct cmd_list_element
*c
, const char *value
)
7106 fprintf_filtered (file
,
7107 _("Controlling the inferior in non-stop mode is %s.\n"),
7112 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7113 struct cmd_list_element
*c
, const char *value
)
7115 fprintf_filtered (file
, _("Resuming the execution of threads "
7116 "of all processes is %s.\n"), value
);
7119 /* Implementation of `siginfo' variable. */
7121 static const struct internalvar_funcs siginfo_funcs
=
7129 _initialize_infrun (void)
7133 struct cmd_list_element
*c
;
7135 add_info ("signals", signals_info
, _("\
7136 What debugger does when program gets various signals.\n\
7137 Specify a signal as argument to print info on that signal only."));
7138 add_info_alias ("handle", "signals", 0);
7140 c
= add_com ("handle", class_run
, handle_command
, _("\
7141 Specify how to handle signals.\n\
7142 Usage: handle SIGNAL [ACTIONS]\n\
7143 Args are signals and actions to apply to those signals.\n\
7144 If no actions are specified, the current settings for the specified signals\n\
7145 will be displayed instead.\n\
7147 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7148 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7149 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7150 The special arg \"all\" is recognized to mean all signals except those\n\
7151 used by the debugger, typically SIGTRAP and SIGINT.\n\
7153 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7154 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7155 Stop means reenter debugger if this signal happens (implies print).\n\
7156 Print means print a message if this signal happens.\n\
7157 Pass means let program see this signal; otherwise program doesn't know.\n\
7158 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7159 Pass and Stop may be combined.\n\
7161 Multiple signals may be specified. Signal numbers and signal names\n\
7162 may be interspersed with actions, with the actions being performed for\n\
7163 all signals cumulatively specified."));
7164 set_cmd_completer (c
, handle_completer
);
7168 add_com ("lz", class_info
, signals_info
, _("\
7169 What debugger does when program gets various signals.\n\
7170 Specify a signal as argument to print info on that signal only."));
7171 add_com ("z", class_run
, xdb_handle_command
, _("\
7172 Specify how to handle a signal.\n\
7173 Args are signals and actions to apply to those signals.\n\
7174 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7175 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7176 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7177 The special arg \"all\" is recognized to mean all signals except those\n\
7178 used by the debugger, typically SIGTRAP and SIGINT.\n\
7179 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7180 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7181 nopass), \"Q\" (noprint)\n\
7182 Stop means reenter debugger if this signal happens (implies print).\n\
7183 Print means print a message if this signal happens.\n\
7184 Pass means let program see this signal; otherwise program doesn't know.\n\
7185 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7186 Pass and Stop may be combined."));
7190 stop_command
= add_cmd ("stop", class_obscure
,
7191 not_just_help_class_command
, _("\
7192 There is no `stop' command, but you can set a hook on `stop'.\n\
7193 This allows you to set a list of commands to be run each time execution\n\
7194 of the program stops."), &cmdlist
);
7196 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7197 Set inferior debugging."), _("\
7198 Show inferior debugging."), _("\
7199 When non-zero, inferior specific debugging is enabled."),
7202 &setdebuglist
, &showdebuglist
);
7204 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7205 &debug_displaced
, _("\
7206 Set displaced stepping debugging."), _("\
7207 Show displaced stepping debugging."), _("\
7208 When non-zero, displaced stepping specific debugging is enabled."),
7210 show_debug_displaced
,
7211 &setdebuglist
, &showdebuglist
);
7213 add_setshow_boolean_cmd ("non-stop", no_class
,
7215 Set whether gdb controls the inferior in non-stop mode."), _("\
7216 Show whether gdb controls the inferior in non-stop mode."), _("\
7217 When debugging a multi-threaded program and this setting is\n\
7218 off (the default, also called all-stop mode), when one thread stops\n\
7219 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7220 all other threads in the program while you interact with the thread of\n\
7221 interest. When you continue or step a thread, you can allow the other\n\
7222 threads to run, or have them remain stopped, but while you inspect any\n\
7223 thread's state, all threads stop.\n\
7225 In non-stop mode, when one thread stops, other threads can continue\n\
7226 to run freely. You'll be able to step each thread independently,\n\
7227 leave it stopped or free to run as needed."),
7233 numsigs
= (int) GDB_SIGNAL_LAST
;
7234 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7235 signal_print
= (unsigned char *)
7236 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7237 signal_program
= (unsigned char *)
7238 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7239 signal_pass
= (unsigned char *)
7240 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7241 for (i
= 0; i
< numsigs
; i
++)
7244 signal_print
[i
] = 1;
7245 signal_program
[i
] = 1;
7248 /* Signals caused by debugger's own actions
7249 should not be given to the program afterwards. */
7250 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7251 signal_program
[GDB_SIGNAL_INT
] = 0;
7253 /* Signals that are not errors should not normally enter the debugger. */
7254 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7255 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7256 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7257 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7258 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7259 signal_print
[GDB_SIGNAL_PROF
] = 0;
7260 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7261 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7262 signal_stop
[GDB_SIGNAL_IO
] = 0;
7263 signal_print
[GDB_SIGNAL_IO
] = 0;
7264 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7265 signal_print
[GDB_SIGNAL_POLL
] = 0;
7266 signal_stop
[GDB_SIGNAL_URG
] = 0;
7267 signal_print
[GDB_SIGNAL_URG
] = 0;
7268 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7269 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7270 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7271 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7273 /* These signals are used internally by user-level thread
7274 implementations. (See signal(5) on Solaris.) Like the above
7275 signals, a healthy program receives and handles them as part of
7276 its normal operation. */
7277 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7278 signal_print
[GDB_SIGNAL_LWP
] = 0;
7279 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7280 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7281 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7282 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7284 /* Update cached state. */
7285 signal_cache_update (-1);
7287 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7288 &stop_on_solib_events
, _("\
7289 Set stopping for shared library events."), _("\
7290 Show stopping for shared library events."), _("\
7291 If nonzero, gdb will give control to the user when the dynamic linker\n\
7292 notifies gdb of shared library events. The most common event of interest\n\
7293 to the user would be loading/unloading of a new library."),
7295 show_stop_on_solib_events
,
7296 &setlist
, &showlist
);
7298 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7299 follow_fork_mode_kind_names
,
7300 &follow_fork_mode_string
, _("\
7301 Set debugger response to a program call of fork or vfork."), _("\
7302 Show debugger response to a program call of fork or vfork."), _("\
7303 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7304 parent - the original process is debugged after a fork\n\
7305 child - the new process is debugged after a fork\n\
7306 The unfollowed process will continue to run.\n\
7307 By default, the debugger will follow the parent process."),
7309 show_follow_fork_mode_string
,
7310 &setlist
, &showlist
);
7312 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7313 follow_exec_mode_names
,
7314 &follow_exec_mode_string
, _("\
7315 Set debugger response to a program call of exec."), _("\
7316 Show debugger response to a program call of exec."), _("\
7317 An exec call replaces the program image of a process.\n\
7319 follow-exec-mode can be:\n\
7321 new - the debugger creates a new inferior and rebinds the process\n\
7322 to this new inferior. The program the process was running before\n\
7323 the exec call can be restarted afterwards by restarting the original\n\
7326 same - the debugger keeps the process bound to the same inferior.\n\
7327 The new executable image replaces the previous executable loaded in\n\
7328 the inferior. Restarting the inferior after the exec call restarts\n\
7329 the executable the process was running after the exec call.\n\
7331 By default, the debugger will use the same inferior."),
7333 show_follow_exec_mode_string
,
7334 &setlist
, &showlist
);
7336 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7337 scheduler_enums
, &scheduler_mode
, _("\
7338 Set mode for locking scheduler during execution."), _("\
7339 Show mode for locking scheduler during execution."), _("\
7340 off == no locking (threads may preempt at any time)\n\
7341 on == full locking (no thread except the current thread may run)\n\
7342 step == scheduler locked during every single-step operation.\n\
7343 In this mode, no other thread may run during a step command.\n\
7344 Other threads may run while stepping over a function call ('next')."),
7345 set_schedlock_func
, /* traps on target vector */
7346 show_scheduler_mode
,
7347 &setlist
, &showlist
);
7349 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7350 Set mode for resuming threads of all processes."), _("\
7351 Show mode for resuming threads of all processes."), _("\
7352 When on, execution commands (such as 'continue' or 'next') resume all\n\
7353 threads of all processes. When off (which is the default), execution\n\
7354 commands only resume the threads of the current process. The set of\n\
7355 threads that are resumed is further refined by the scheduler-locking\n\
7356 mode (see help set scheduler-locking)."),
7358 show_schedule_multiple
,
7359 &setlist
, &showlist
);
7361 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7362 Set mode of the step operation."), _("\
7363 Show mode of the step operation."), _("\
7364 When set, doing a step over a function without debug line information\n\
7365 will stop at the first instruction of that function. Otherwise, the\n\
7366 function is skipped and the step command stops at a different source line."),
7368 show_step_stop_if_no_debug
,
7369 &setlist
, &showlist
);
7371 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
7372 &can_use_displaced_stepping
, _("\
7373 Set debugger's willingness to use displaced stepping."), _("\
7374 Show debugger's willingness to use displaced stepping."), _("\
7375 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7376 supported by the target architecture. If off, gdb will not use displaced\n\
7377 stepping to step over breakpoints, even if such is supported by the target\n\
7378 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7379 if the target architecture supports it and non-stop mode is active, but will not\n\
7380 use it in all-stop mode (see help set non-stop)."),
7382 show_can_use_displaced_stepping
,
7383 &setlist
, &showlist
);
7385 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7386 &exec_direction
, _("Set direction of execution.\n\
7387 Options are 'forward' or 'reverse'."),
7388 _("Show direction of execution (forward/reverse)."),
7389 _("Tells gdb whether to execute forward or backward."),
7390 set_exec_direction_func
, show_exec_direction_func
,
7391 &setlist
, &showlist
);
7393 /* Set/show detach-on-fork: user-settable mode. */
7395 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7396 Set whether gdb will detach the child of a fork."), _("\
7397 Show whether gdb will detach the child of a fork."), _("\
7398 Tells gdb whether to detach the child of a fork."),
7399 NULL
, NULL
, &setlist
, &showlist
);
7401 /* Set/show disable address space randomization mode. */
7403 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7404 &disable_randomization
, _("\
7405 Set disabling of debuggee's virtual address space randomization."), _("\
7406 Show disabling of debuggee's virtual address space randomization."), _("\
7407 When this mode is on (which is the default), randomization of the virtual\n\
7408 address space is disabled. Standalone programs run with the randomization\n\
7409 enabled by default on some platforms."),
7410 &set_disable_randomization
,
7411 &show_disable_randomization
,
7412 &setlist
, &showlist
);
7414 /* ptid initializations */
7415 inferior_ptid
= null_ptid
;
7416 target_last_wait_ptid
= minus_one_ptid
;
7418 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7419 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7420 observer_attach_thread_exit (infrun_thread_thread_exit
);
7421 observer_attach_inferior_exit (infrun_inferior_exit
);
7423 /* Explicitly create without lookup, since that tries to create a
7424 value with a void typed value, and when we get here, gdbarch
7425 isn't initialized yet. At this point, we're quite sure there
7426 isn't another convenience variable of the same name. */
7427 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7429 add_setshow_boolean_cmd ("observer", no_class
,
7430 &observer_mode_1
, _("\
7431 Set whether gdb controls the inferior in observer mode."), _("\
7432 Show whether gdb controls the inferior in observer mode."), _("\
7433 In observer mode, GDB can get data from the inferior, but not\n\
7434 affect its execution. Registers and memory may not be changed,\n\
7435 breakpoints may not be set, and the program cannot be interrupted\n\