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 static 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 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3046 for (frame
= get_prev_frame (frame
);
3048 frame
= get_prev_frame (frame
))
3050 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3052 if (get_frame_type (frame
) != INLINE_FRAME
)
3059 /* Auxiliary function that handles syscall entry/return events.
3060 It returns 1 if the inferior should keep going (and GDB
3061 should ignore the event), or 0 if the event deserves to be
3065 handle_syscall_event (struct execution_control_state
*ecs
)
3067 struct regcache
*regcache
;
3068 struct gdbarch
*gdbarch
;
3071 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3072 context_switch (ecs
->ptid
);
3074 regcache
= get_thread_regcache (ecs
->ptid
);
3075 gdbarch
= get_regcache_arch (regcache
);
3076 syscall_number
= ecs
->ws
.value
.syscall_number
;
3077 stop_pc
= regcache_read_pc (regcache
);
3079 if (catch_syscall_enabled () > 0
3080 && catching_syscall_number (syscall_number
) > 0)
3083 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3086 ecs
->event_thread
->control
.stop_bpstat
3087 = bpstat_stop_status (get_regcache_aspace (regcache
),
3088 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3090 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3092 if (!ecs
->random_signal
)
3094 /* Catchpoint hit. */
3095 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3100 /* If no catchpoint triggered for this, then keep going. */
3101 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3106 /* Clear the supplied execution_control_state's stop_func_* fields. */
3109 clear_stop_func (struct execution_control_state
*ecs
)
3111 ecs
->stop_func_filled_in
= 0;
3112 ecs
->stop_func_start
= 0;
3113 ecs
->stop_func_end
= 0;
3114 ecs
->stop_func_name
= NULL
;
3117 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3120 fill_in_stop_func (struct gdbarch
*gdbarch
,
3121 struct execution_control_state
*ecs
)
3123 if (!ecs
->stop_func_filled_in
)
3125 /* Don't care about return value; stop_func_start and stop_func_name
3126 will both be 0 if it doesn't work. */
3127 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3128 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3129 ecs
->stop_func_start
3130 += gdbarch_deprecated_function_start_offset (gdbarch
);
3132 ecs
->stop_func_filled_in
= 1;
3136 /* Given an execution control state that has been freshly filled in
3137 by an event from the inferior, figure out what it means and take
3138 appropriate action. */
3141 handle_inferior_event (struct execution_control_state
*ecs
)
3143 struct frame_info
*frame
;
3144 struct gdbarch
*gdbarch
;
3145 int stopped_by_watchpoint
;
3146 int stepped_after_stopped_by_watchpoint
= 0;
3147 struct symtab_and_line stop_pc_sal
;
3148 enum stop_kind stop_soon
;
3150 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3152 /* We had an event in the inferior, but we are not interested in
3153 handling it at this level. The lower layers have already
3154 done what needs to be done, if anything.
3156 One of the possible circumstances for this is when the
3157 inferior produces output for the console. The inferior has
3158 not stopped, and we are ignoring the event. Another possible
3159 circumstance is any event which the lower level knows will be
3160 reported multiple times without an intervening resume. */
3162 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3163 prepare_to_wait (ecs
);
3167 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3168 && target_can_async_p () && !sync_execution
)
3170 /* There were no unwaited-for children left in the target, but,
3171 we're not synchronously waiting for events either. Just
3172 ignore. Otherwise, if we were running a synchronous
3173 execution command, we need to cancel it and give the user
3174 back the terminal. */
3176 fprintf_unfiltered (gdb_stdlog
,
3177 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3178 prepare_to_wait (ecs
);
3182 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3183 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3184 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
3186 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3189 stop_soon
= inf
->control
.stop_soon
;
3192 stop_soon
= NO_STOP_QUIETLY
;
3194 /* Cache the last pid/waitstatus. */
3195 target_last_wait_ptid
= ecs
->ptid
;
3196 target_last_waitstatus
= ecs
->ws
;
3198 /* Always clear state belonging to the previous time we stopped. */
3199 stop_stack_dummy
= STOP_NONE
;
3201 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3203 /* No unwaited-for children left. IOW, all resumed children
3206 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3208 stop_print_frame
= 0;
3209 stop_stepping (ecs
);
3213 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3214 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
3216 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3217 /* If it's a new thread, add it to the thread database. */
3218 if (ecs
->event_thread
== NULL
)
3219 ecs
->event_thread
= add_thread (ecs
->ptid
);
3222 /* Dependent on valid ECS->EVENT_THREAD. */
3223 adjust_pc_after_break (ecs
);
3225 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3226 reinit_frame_cache ();
3228 breakpoint_retire_moribund ();
3230 /* First, distinguish signals caused by the debugger from signals
3231 that have to do with the program's own actions. Note that
3232 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3233 on the operating system version. Here we detect when a SIGILL or
3234 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3235 something similar for SIGSEGV, since a SIGSEGV will be generated
3236 when we're trying to execute a breakpoint instruction on a
3237 non-executable stack. This happens for call dummy breakpoints
3238 for architectures like SPARC that place call dummies on the
3240 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3241 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3242 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3243 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3245 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3247 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3248 regcache_read_pc (regcache
)))
3251 fprintf_unfiltered (gdb_stdlog
,
3252 "infrun: Treating signal as SIGTRAP\n");
3253 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3257 /* Mark the non-executing threads accordingly. In all-stop, all
3258 threads of all processes are stopped when we get any event
3259 reported. In non-stop mode, only the event thread stops. If
3260 we're handling a process exit in non-stop mode, there's nothing
3261 to do, as threads of the dead process are gone, and threads of
3262 any other process were left running. */
3264 set_executing (minus_one_ptid
, 0);
3265 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3266 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3267 set_executing (ecs
->ptid
, 0);
3269 switch (infwait_state
)
3271 case infwait_thread_hop_state
:
3273 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
3276 case infwait_normal_state
:
3278 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
3281 case infwait_step_watch_state
:
3283 fprintf_unfiltered (gdb_stdlog
,
3284 "infrun: infwait_step_watch_state\n");
3286 stepped_after_stopped_by_watchpoint
= 1;
3289 case infwait_nonstep_watch_state
:
3291 fprintf_unfiltered (gdb_stdlog
,
3292 "infrun: infwait_nonstep_watch_state\n");
3293 insert_breakpoints ();
3295 /* FIXME-maybe: is this cleaner than setting a flag? Does it
3296 handle things like signals arriving and other things happening
3297 in combination correctly? */
3298 stepped_after_stopped_by_watchpoint
= 1;
3302 internal_error (__FILE__
, __LINE__
, _("bad switch"));
3305 infwait_state
= infwait_normal_state
;
3306 waiton_ptid
= pid_to_ptid (-1);
3308 switch (ecs
->ws
.kind
)
3310 case TARGET_WAITKIND_LOADED
:
3312 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3313 /* Ignore gracefully during startup of the inferior, as it might
3314 be the shell which has just loaded some objects, otherwise
3315 add the symbols for the newly loaded objects. Also ignore at
3316 the beginning of an attach or remote session; we will query
3317 the full list of libraries once the connection is
3319 if (stop_soon
== NO_STOP_QUIETLY
)
3321 struct regcache
*regcache
;
3323 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3324 context_switch (ecs
->ptid
);
3325 regcache
= get_thread_regcache (ecs
->ptid
);
3327 handle_solib_event ();
3329 ecs
->event_thread
->control
.stop_bpstat
3330 = bpstat_stop_status (get_regcache_aspace (regcache
),
3331 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3333 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3335 if (!ecs
->random_signal
)
3337 /* A catchpoint triggered. */
3338 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3339 goto process_event_stop_test
;
3342 /* If requested, stop when the dynamic linker notifies
3343 gdb of events. This allows the user to get control
3344 and place breakpoints in initializer routines for
3345 dynamically loaded objects (among other things). */
3346 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3347 if (stop_on_solib_events
)
3349 /* Make sure we print "Stopped due to solib-event" in
3351 stop_print_frame
= 1;
3353 stop_stepping (ecs
);
3358 /* If we are skipping through a shell, or through shared library
3359 loading that we aren't interested in, resume the program. If
3360 we're running the program normally, also resume. But stop if
3361 we're attaching or setting up a remote connection. */
3362 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3364 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3365 context_switch (ecs
->ptid
);
3367 /* Loading of shared libraries might have changed breakpoint
3368 addresses. Make sure new breakpoints are inserted. */
3369 if (stop_soon
== NO_STOP_QUIETLY
3370 && !breakpoints_always_inserted_mode ())
3371 insert_breakpoints ();
3372 resume (0, GDB_SIGNAL_0
);
3373 prepare_to_wait (ecs
);
3379 case TARGET_WAITKIND_SPURIOUS
:
3381 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3382 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3383 context_switch (ecs
->ptid
);
3384 resume (0, GDB_SIGNAL_0
);
3385 prepare_to_wait (ecs
);
3388 case TARGET_WAITKIND_EXITED
:
3389 case TARGET_WAITKIND_SIGNALLED
:
3392 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3393 fprintf_unfiltered (gdb_stdlog
,
3394 "infrun: TARGET_WAITKIND_EXITED\n");
3396 fprintf_unfiltered (gdb_stdlog
,
3397 "infrun: TARGET_WAITKIND_SIGNALLED\n");
3400 inferior_ptid
= ecs
->ptid
;
3401 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3402 set_current_program_space (current_inferior ()->pspace
);
3403 handle_vfork_child_exec_or_exit (0);
3404 target_terminal_ours (); /* Must do this before mourn anyway. */
3406 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3408 /* Record the exit code in the convenience variable $_exitcode, so
3409 that the user can inspect this again later. */
3410 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3411 (LONGEST
) ecs
->ws
.value
.integer
);
3413 /* Also record this in the inferior itself. */
3414 current_inferior ()->has_exit_code
= 1;
3415 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3417 print_exited_reason (ecs
->ws
.value
.integer
);
3420 print_signal_exited_reason (ecs
->ws
.value
.sig
);
3422 gdb_flush (gdb_stdout
);
3423 target_mourn_inferior ();
3424 singlestep_breakpoints_inserted_p
= 0;
3425 cancel_single_step_breakpoints ();
3426 stop_print_frame
= 0;
3427 stop_stepping (ecs
);
3430 /* The following are the only cases in which we keep going;
3431 the above cases end in a continue or goto. */
3432 case TARGET_WAITKIND_FORKED
:
3433 case TARGET_WAITKIND_VFORKED
:
3436 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3437 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3439 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
3442 /* Check whether the inferior is displaced stepping. */
3444 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3445 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3446 struct displaced_step_inferior_state
*displaced
3447 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3449 /* If checking displaced stepping is supported, and thread
3450 ecs->ptid is displaced stepping. */
3451 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3453 struct inferior
*parent_inf
3454 = find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3455 struct regcache
*child_regcache
;
3456 CORE_ADDR parent_pc
;
3458 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3459 indicating that the displaced stepping of syscall instruction
3460 has been done. Perform cleanup for parent process here. Note
3461 that this operation also cleans up the child process for vfork,
3462 because their pages are shared. */
3463 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
3465 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3467 /* Restore scratch pad for child process. */
3468 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3471 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3472 the child's PC is also within the scratchpad. Set the child's PC
3473 to the parent's PC value, which has already been fixed up.
3474 FIXME: we use the parent's aspace here, although we're touching
3475 the child, because the child hasn't been added to the inferior
3476 list yet at this point. */
3479 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3481 parent_inf
->aspace
);
3482 /* Read PC value of parent process. */
3483 parent_pc
= regcache_read_pc (regcache
);
3485 if (debug_displaced
)
3486 fprintf_unfiltered (gdb_stdlog
,
3487 "displaced: write child pc from %s to %s\n",
3489 regcache_read_pc (child_regcache
)),
3490 paddress (gdbarch
, parent_pc
));
3492 regcache_write_pc (child_regcache
, parent_pc
);
3496 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3497 context_switch (ecs
->ptid
);
3499 /* Immediately detach breakpoints from the child before there's
3500 any chance of letting the user delete breakpoints from the
3501 breakpoint lists. If we don't do this early, it's easy to
3502 leave left over traps in the child, vis: "break foo; catch
3503 fork; c; <fork>; del; c; <child calls foo>". We only follow
3504 the fork on the last `continue', and by that time the
3505 breakpoint at "foo" is long gone from the breakpoint table.
3506 If we vforked, then we don't need to unpatch here, since both
3507 parent and child are sharing the same memory pages; we'll
3508 need to unpatch at follow/detach time instead to be certain
3509 that new breakpoints added between catchpoint hit time and
3510 vfork follow are detached. */
3511 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3513 /* This won't actually modify the breakpoint list, but will
3514 physically remove the breakpoints from the child. */
3515 detach_breakpoints (ecs
->ws
.value
.related_pid
);
3518 if (singlestep_breakpoints_inserted_p
)
3520 /* Pull the single step breakpoints out of the target. */
3521 remove_single_step_breakpoints ();
3522 singlestep_breakpoints_inserted_p
= 0;
3525 /* In case the event is caught by a catchpoint, remember that
3526 the event is to be followed at the next resume of the thread,
3527 and not immediately. */
3528 ecs
->event_thread
->pending_follow
= ecs
->ws
;
3530 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3532 ecs
->event_thread
->control
.stop_bpstat
3533 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3534 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3536 /* Note that we're interested in knowing the bpstat actually
3537 causes a stop, not just if it may explain the signal.
3538 Software watchpoints, for example, always appear in the
3541 = !bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
);
3543 /* If no catchpoint triggered for this, then keep going. */
3544 if (ecs
->random_signal
)
3550 = (follow_fork_mode_string
== follow_fork_mode_child
);
3552 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3554 should_resume
= follow_fork ();
3557 child
= ecs
->ws
.value
.related_pid
;
3559 /* In non-stop mode, also resume the other branch. */
3560 if (non_stop
&& !detach_fork
)
3563 switch_to_thread (parent
);
3565 switch_to_thread (child
);
3567 ecs
->event_thread
= inferior_thread ();
3568 ecs
->ptid
= inferior_ptid
;
3573 switch_to_thread (child
);
3575 switch_to_thread (parent
);
3577 ecs
->event_thread
= inferior_thread ();
3578 ecs
->ptid
= inferior_ptid
;
3583 stop_stepping (ecs
);
3586 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3587 goto process_event_stop_test
;
3589 case TARGET_WAITKIND_VFORK_DONE
:
3590 /* Done with the shared memory region. Re-insert breakpoints in
3591 the parent, and keep going. */
3594 fprintf_unfiltered (gdb_stdlog
,
3595 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3597 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3598 context_switch (ecs
->ptid
);
3600 current_inferior ()->waiting_for_vfork_done
= 0;
3601 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
3602 /* This also takes care of reinserting breakpoints in the
3603 previously locked inferior. */
3607 case TARGET_WAITKIND_EXECD
:
3609 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
3611 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3612 context_switch (ecs
->ptid
);
3614 singlestep_breakpoints_inserted_p
= 0;
3615 cancel_single_step_breakpoints ();
3617 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3619 /* Do whatever is necessary to the parent branch of the vfork. */
3620 handle_vfork_child_exec_or_exit (1);
3622 /* This causes the eventpoints and symbol table to be reset.
3623 Must do this now, before trying to determine whether to
3625 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
3627 ecs
->event_thread
->control
.stop_bpstat
3628 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3629 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3631 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3633 /* Note that this may be referenced from inside
3634 bpstat_stop_status above, through inferior_has_execd. */
3635 xfree (ecs
->ws
.value
.execd_pathname
);
3636 ecs
->ws
.value
.execd_pathname
= NULL
;
3638 /* If no catchpoint triggered for this, then keep going. */
3639 if (ecs
->random_signal
)
3641 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3645 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3646 goto process_event_stop_test
;
3648 /* Be careful not to try to gather much state about a thread
3649 that's in a syscall. It's frequently a losing proposition. */
3650 case TARGET_WAITKIND_SYSCALL_ENTRY
:
3652 fprintf_unfiltered (gdb_stdlog
,
3653 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3654 /* Getting the current syscall number. */
3655 if (handle_syscall_event (ecs
) != 0)
3657 goto process_event_stop_test
;
3659 /* Before examining the threads further, step this thread to
3660 get it entirely out of the syscall. (We get notice of the
3661 event when the thread is just on the verge of exiting a
3662 syscall. Stepping one instruction seems to get it back
3664 case TARGET_WAITKIND_SYSCALL_RETURN
:
3666 fprintf_unfiltered (gdb_stdlog
,
3667 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3668 if (handle_syscall_event (ecs
) != 0)
3670 goto process_event_stop_test
;
3672 case TARGET_WAITKIND_STOPPED
:
3674 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
3675 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
3678 case TARGET_WAITKIND_NO_HISTORY
:
3680 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
3681 /* Reverse execution: target ran out of history info. */
3683 /* Pull the single step breakpoints out of the target. */
3684 if (singlestep_breakpoints_inserted_p
)
3686 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3687 context_switch (ecs
->ptid
);
3688 remove_single_step_breakpoints ();
3689 singlestep_breakpoints_inserted_p
= 0;
3691 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3692 print_no_history_reason ();
3693 stop_stepping (ecs
);
3697 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
3699 /* Do we need to clean up the state of a thread that has
3700 completed a displaced single-step? (Doing so usually affects
3701 the PC, so do it here, before we set stop_pc.) */
3702 displaced_step_fixup (ecs
->ptid
,
3703 ecs
->event_thread
->suspend
.stop_signal
);
3705 /* If we either finished a single-step or hit a breakpoint, but
3706 the user wanted this thread to be stopped, pretend we got a
3707 SIG0 (generic unsignaled stop). */
3709 if (ecs
->event_thread
->stop_requested
3710 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3711 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3714 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3718 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3719 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3720 struct cleanup
*old_chain
= save_inferior_ptid ();
3722 inferior_ptid
= ecs
->ptid
;
3724 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
3725 paddress (gdbarch
, stop_pc
));
3726 if (target_stopped_by_watchpoint ())
3730 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
3732 if (target_stopped_data_address (¤t_target
, &addr
))
3733 fprintf_unfiltered (gdb_stdlog
,
3734 "infrun: stopped data address = %s\n",
3735 paddress (gdbarch
, addr
));
3737 fprintf_unfiltered (gdb_stdlog
,
3738 "infrun: (no data address available)\n");
3741 do_cleanups (old_chain
);
3744 if (stepping_past_singlestep_breakpoint
)
3746 gdb_assert (singlestep_breakpoints_inserted_p
);
3747 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
3748 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
3750 stepping_past_singlestep_breakpoint
= 0;
3752 /* We've either finished single-stepping past the single-step
3753 breakpoint, or stopped for some other reason. It would be nice if
3754 we could tell, but we can't reliably. */
3755 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3758 fprintf_unfiltered (gdb_stdlog
,
3759 "infrun: stepping_past_"
3760 "singlestep_breakpoint\n");
3761 /* Pull the single step breakpoints out of the target. */
3762 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3763 context_switch (ecs
->ptid
);
3764 remove_single_step_breakpoints ();
3765 singlestep_breakpoints_inserted_p
= 0;
3767 ecs
->random_signal
= 0;
3768 ecs
->event_thread
->control
.trap_expected
= 0;
3770 context_switch (saved_singlestep_ptid
);
3771 if (deprecated_context_hook
)
3772 deprecated_context_hook (pid_to_thread_id (saved_singlestep_ptid
));
3774 resume (1, GDB_SIGNAL_0
);
3775 prepare_to_wait (ecs
);
3780 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
3782 /* In non-stop mode, there's never a deferred_step_ptid set. */
3783 gdb_assert (!non_stop
);
3785 /* If we stopped for some other reason than single-stepping, ignore
3786 the fact that we were supposed to switch back. */
3787 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3790 fprintf_unfiltered (gdb_stdlog
,
3791 "infrun: handling deferred step\n");
3793 /* Pull the single step breakpoints out of the target. */
3794 if (singlestep_breakpoints_inserted_p
)
3796 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3797 context_switch (ecs
->ptid
);
3798 remove_single_step_breakpoints ();
3799 singlestep_breakpoints_inserted_p
= 0;
3802 ecs
->event_thread
->control
.trap_expected
= 0;
3804 context_switch (deferred_step_ptid
);
3805 deferred_step_ptid
= null_ptid
;
3806 /* Suppress spurious "Switching to ..." message. */
3807 previous_inferior_ptid
= inferior_ptid
;
3809 resume (1, GDB_SIGNAL_0
);
3810 prepare_to_wait (ecs
);
3814 deferred_step_ptid
= null_ptid
;
3817 /* See if a thread hit a thread-specific breakpoint that was meant for
3818 another thread. If so, then step that thread past the breakpoint,
3821 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3823 int thread_hop_needed
= 0;
3824 struct address_space
*aspace
=
3825 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
3827 /* Check if a regular breakpoint has been hit before checking
3828 for a potential single step breakpoint. Otherwise, GDB will
3829 not see this breakpoint hit when stepping onto breakpoints. */
3830 if (regular_breakpoint_inserted_here_p (aspace
, stop_pc
))
3832 ecs
->random_signal
= 0;
3833 if (!breakpoint_thread_match (aspace
, stop_pc
, ecs
->ptid
))
3834 thread_hop_needed
= 1;
3836 else if (singlestep_breakpoints_inserted_p
)
3838 /* We have not context switched yet, so this should be true
3839 no matter which thread hit the singlestep breakpoint. */
3840 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
3842 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
3844 target_pid_to_str (ecs
->ptid
));
3846 ecs
->random_signal
= 0;
3847 /* The call to in_thread_list is necessary because PTIDs sometimes
3848 change when we go from single-threaded to multi-threaded. If
3849 the singlestep_ptid is still in the list, assume that it is
3850 really different from ecs->ptid. */
3851 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
3852 && in_thread_list (singlestep_ptid
))
3854 /* If the PC of the thread we were trying to single-step
3855 has changed, discard this event (which we were going
3856 to ignore anyway), and pretend we saw that thread
3857 trap. This prevents us continuously moving the
3858 single-step breakpoint forward, one instruction at a
3859 time. If the PC has changed, then the thread we were
3860 trying to single-step has trapped or been signalled,
3861 but the event has not been reported to GDB yet.
3863 There might be some cases where this loses signal
3864 information, if a signal has arrived at exactly the
3865 same time that the PC changed, but this is the best
3866 we can do with the information available. Perhaps we
3867 should arrange to report all events for all threads
3868 when they stop, or to re-poll the remote looking for
3869 this particular thread (i.e. temporarily enable
3872 CORE_ADDR new_singlestep_pc
3873 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
3875 if (new_singlestep_pc
!= singlestep_pc
)
3877 enum gdb_signal stop_signal
;
3880 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
3881 " but expected thread advanced also\n");
3883 /* The current context still belongs to
3884 singlestep_ptid. Don't swap here, since that's
3885 the context we want to use. Just fudge our
3886 state and continue. */
3887 stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
3888 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3889 ecs
->ptid
= singlestep_ptid
;
3890 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3891 ecs
->event_thread
->suspend
.stop_signal
= stop_signal
;
3892 stop_pc
= new_singlestep_pc
;
3897 fprintf_unfiltered (gdb_stdlog
,
3898 "infrun: unexpected thread\n");
3900 thread_hop_needed
= 1;
3901 stepping_past_singlestep_breakpoint
= 1;
3902 saved_singlestep_ptid
= singlestep_ptid
;
3907 if (thread_hop_needed
)
3909 struct regcache
*thread_regcache
;
3910 int remove_status
= 0;
3913 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
3915 /* Switch context before touching inferior memory, the
3916 previous thread may have exited. */
3917 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
3918 context_switch (ecs
->ptid
);
3920 /* Saw a breakpoint, but it was hit by the wrong thread.
3923 if (singlestep_breakpoints_inserted_p
)
3925 /* Pull the single step breakpoints out of the target. */
3926 remove_single_step_breakpoints ();
3927 singlestep_breakpoints_inserted_p
= 0;
3930 /* If the arch can displace step, don't remove the
3932 thread_regcache
= get_thread_regcache (ecs
->ptid
);
3933 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
3934 remove_status
= remove_breakpoints ();
3936 /* Did we fail to remove breakpoints? If so, try
3937 to set the PC past the bp. (There's at least
3938 one situation in which we can fail to remove
3939 the bp's: On HP-UX's that use ttrace, we can't
3940 change the address space of a vforking child
3941 process until the child exits (well, okay, not
3942 then either :-) or execs. */
3943 if (remove_status
!= 0)
3944 error (_("Cannot step over breakpoint hit in wrong thread"));
3949 /* Only need to require the next event from this
3950 thread in all-stop mode. */
3951 waiton_ptid
= ecs
->ptid
;
3952 infwait_state
= infwait_thread_hop_state
;
3955 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3960 else if (singlestep_breakpoints_inserted_p
)
3962 ecs
->random_signal
= 0;
3966 ecs
->random_signal
= 1;
3968 /* See if something interesting happened to the non-current thread. If
3969 so, then switch to that thread. */
3970 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3973 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
3975 context_switch (ecs
->ptid
);
3977 if (deprecated_context_hook
)
3978 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3981 /* At this point, get hold of the now-current thread's frame. */
3982 frame
= get_current_frame ();
3983 gdbarch
= get_frame_arch (frame
);
3985 if (singlestep_breakpoints_inserted_p
)
3987 /* Pull the single step breakpoints out of the target. */
3988 remove_single_step_breakpoints ();
3989 singlestep_breakpoints_inserted_p
= 0;
3992 if (stepped_after_stopped_by_watchpoint
)
3993 stopped_by_watchpoint
= 0;
3995 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
3997 /* If necessary, step over this watchpoint. We'll be back to display
3999 if (stopped_by_watchpoint
4000 && (target_have_steppable_watchpoint
4001 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
4003 /* At this point, we are stopped at an instruction which has
4004 attempted to write to a piece of memory under control of
4005 a watchpoint. The instruction hasn't actually executed
4006 yet. If we were to evaluate the watchpoint expression
4007 now, we would get the old value, and therefore no change
4008 would seem to have occurred.
4010 In order to make watchpoints work `right', we really need
4011 to complete the memory write, and then evaluate the
4012 watchpoint expression. We do this by single-stepping the
4015 It may not be necessary to disable the watchpoint to stop over
4016 it. For example, the PA can (with some kernel cooperation)
4017 single step over a watchpoint without disabling the watchpoint.
4019 It is far more common to need to disable a watchpoint to step
4020 the inferior over it. If we have non-steppable watchpoints,
4021 we must disable the current watchpoint; it's simplest to
4022 disable all watchpoints and breakpoints. */
4025 if (!target_have_steppable_watchpoint
)
4027 remove_breakpoints ();
4028 /* See comment in resume why we need to stop bypassing signals
4029 while breakpoints have been removed. */
4030 target_pass_signals (0, NULL
);
4033 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
4034 target_resume (ecs
->ptid
, hw_step
, GDB_SIGNAL_0
);
4035 waiton_ptid
= ecs
->ptid
;
4036 if (target_have_steppable_watchpoint
)
4037 infwait_state
= infwait_step_watch_state
;
4039 infwait_state
= infwait_nonstep_watch_state
;
4040 prepare_to_wait (ecs
);
4044 clear_stop_func (ecs
);
4045 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4046 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4047 ecs
->event_thread
->control
.stop_step
= 0;
4048 stop_print_frame
= 1;
4049 ecs
->random_signal
= 0;
4050 stopped_by_random_signal
= 0;
4052 /* Hide inlined functions starting here, unless we just performed stepi or
4053 nexti. After stepi and nexti, always show the innermost frame (not any
4054 inline function call sites). */
4055 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4057 struct address_space
*aspace
=
4058 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4060 /* skip_inline_frames is expensive, so we avoid it if we can
4061 determine that the address is one where functions cannot have
4062 been inlined. This improves performance with inferiors that
4063 load a lot of shared libraries, because the solib event
4064 breakpoint is defined as the address of a function (i.e. not
4065 inline). Note that we have to check the previous PC as well
4066 as the current one to catch cases when we have just
4067 single-stepped off a breakpoint prior to reinstating it.
4068 Note that we're assuming that the code we single-step to is
4069 not inline, but that's not definitive: there's nothing
4070 preventing the event breakpoint function from containing
4071 inlined code, and the single-step ending up there. If the
4072 user had set a breakpoint on that inlined code, the missing
4073 skip_inline_frames call would break things. Fortunately
4074 that's an extremely unlikely scenario. */
4075 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4076 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4077 && ecs
->event_thread
->control
.trap_expected
4078 && pc_at_non_inline_function (aspace
,
4079 ecs
->event_thread
->prev_pc
,
4082 skip_inline_frames (ecs
->ptid
);
4084 /* Re-fetch current thread's frame in case that invalidated
4086 frame
= get_current_frame ();
4087 gdbarch
= get_frame_arch (frame
);
4091 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4092 && ecs
->event_thread
->control
.trap_expected
4093 && gdbarch_single_step_through_delay_p (gdbarch
)
4094 && currently_stepping (ecs
->event_thread
))
4096 /* We're trying to step off a breakpoint. Turns out that we're
4097 also on an instruction that needs to be stepped multiple
4098 times before it's been fully executing. E.g., architectures
4099 with a delay slot. It needs to be stepped twice, once for
4100 the instruction and once for the delay slot. */
4101 int step_through_delay
4102 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4104 if (debug_infrun
&& step_through_delay
)
4105 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4106 if (ecs
->event_thread
->control
.step_range_end
== 0
4107 && step_through_delay
)
4109 /* The user issued a continue when stopped at a breakpoint.
4110 Set up for another trap and get out of here. */
4111 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4115 else if (step_through_delay
)
4117 /* The user issued a step when stopped at a breakpoint.
4118 Maybe we should stop, maybe we should not - the delay
4119 slot *might* correspond to a line of source. In any
4120 case, don't decide that here, just set
4121 ecs->stepping_over_breakpoint, making sure we
4122 single-step again before breakpoints are re-inserted. */
4123 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4127 /* Look at the cause of the stop, and decide what to do.
4128 The alternatives are:
4129 1) stop_stepping and return; to really stop and return to the debugger,
4130 2) keep_going and return to start up again
4131 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
4132 3) set ecs->random_signal to 1, and the decision between 1 and 2
4133 will be made according to the signal handling tables. */
4135 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4136 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4137 || stop_soon
== STOP_QUIETLY_REMOTE
)
4139 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4143 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4144 stop_print_frame
= 0;
4145 stop_stepping (ecs
);
4149 /* This is originated from start_remote(), start_inferior() and
4150 shared libraries hook functions. */
4151 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4154 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4155 stop_stepping (ecs
);
4159 /* This originates from attach_command(). We need to overwrite
4160 the stop_signal here, because some kernels don't ignore a
4161 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4162 See more comments in inferior.h. On the other hand, if we
4163 get a non-SIGSTOP, report it to the user - assume the backend
4164 will handle the SIGSTOP if it should show up later.
4166 Also consider that the attach is complete when we see a
4167 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4168 target extended-remote report it instead of a SIGSTOP
4169 (e.g. gdbserver). We already rely on SIGTRAP being our
4170 signal, so this is no exception.
4172 Also consider that the attach is complete when we see a
4173 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4174 the target to stop all threads of the inferior, in case the
4175 low level attach operation doesn't stop them implicitly. If
4176 they weren't stopped implicitly, then the stub will report a
4177 GDB_SIGNAL_0, meaning: stopped for no particular reason
4178 other than GDB's request. */
4179 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4180 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
4181 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4182 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
4184 stop_stepping (ecs
);
4185 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4189 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4190 handles this event. */
4191 ecs
->event_thread
->control
.stop_bpstat
4192 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4193 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4195 /* Following in case break condition called a
4197 stop_print_frame
= 1;
4199 /* This is where we handle "moribund" watchpoints. Unlike
4200 software breakpoints traps, hardware watchpoint traps are
4201 always distinguishable from random traps. If no high-level
4202 watchpoint is associated with the reported stop data address
4203 anymore, then the bpstat does not explain the signal ---
4204 simply make sure to ignore it if `stopped_by_watchpoint' is
4208 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4209 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4210 && stopped_by_watchpoint
)
4211 fprintf_unfiltered (gdb_stdlog
,
4212 "infrun: no user watchpoint explains "
4213 "watchpoint SIGTRAP, ignoring\n");
4215 /* NOTE: cagney/2003-03-29: These two checks for a random signal
4216 at one stage in the past included checks for an inferior
4217 function call's call dummy's return breakpoint. The original
4218 comment, that went with the test, read:
4220 ``End of a stack dummy. Some systems (e.g. Sony news) give
4221 another signal besides SIGTRAP, so check here as well as
4224 If someone ever tries to get call dummys on a
4225 non-executable stack to work (where the target would stop
4226 with something like a SIGSEGV), then those tests might need
4227 to be re-instated. Given, however, that the tests were only
4228 enabled when momentary breakpoints were not being used, I
4229 suspect that it won't be the case.
4231 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4232 be necessary for call dummies on a non-executable stack on
4235 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4237 = !(bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4238 || stopped_by_watchpoint
4239 || ecs
->event_thread
->control
.trap_expected
4240 || (ecs
->event_thread
->control
.step_range_end
4241 && (ecs
->event_thread
->control
.step_resume_breakpoint
4245 ecs
->random_signal
= !bpstat_explains_signal
4246 (ecs
->event_thread
->control
.stop_bpstat
);
4247 if (!ecs
->random_signal
)
4248 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
4252 /* When we reach this point, we've pretty much decided
4253 that the reason for stopping must've been a random
4254 (unexpected) signal. */
4257 ecs
->random_signal
= 1;
4259 process_event_stop_test
:
4261 /* Re-fetch current thread's frame in case we did a
4262 "goto process_event_stop_test" above. */
4263 frame
= get_current_frame ();
4264 gdbarch
= get_frame_arch (frame
);
4266 /* For the program's own signals, act according to
4267 the signal handling tables. */
4269 if (ecs
->random_signal
)
4271 /* Signal not for debugging purposes. */
4273 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
4276 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
4277 ecs
->event_thread
->suspend
.stop_signal
);
4279 stopped_by_random_signal
= 1;
4281 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4284 target_terminal_ours_for_output ();
4285 print_signal_received_reason
4286 (ecs
->event_thread
->suspend
.stop_signal
);
4288 /* Always stop on signals if we're either just gaining control
4289 of the program, or the user explicitly requested this thread
4290 to remain stopped. */
4291 if (stop_soon
!= NO_STOP_QUIETLY
4292 || ecs
->event_thread
->stop_requested
4294 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4296 stop_stepping (ecs
);
4299 /* If not going to stop, give terminal back
4300 if we took it away. */
4302 target_terminal_inferior ();
4304 /* Clear the signal if it should not be passed. */
4305 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4306 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4308 if (ecs
->event_thread
->prev_pc
== stop_pc
4309 && ecs
->event_thread
->control
.trap_expected
4310 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4312 /* We were just starting a new sequence, attempting to
4313 single-step off of a breakpoint and expecting a SIGTRAP.
4314 Instead this signal arrives. This signal will take us out
4315 of the stepping range so GDB needs to remember to, when
4316 the signal handler returns, resume stepping off that
4318 /* To simplify things, "continue" is forced to use the same
4319 code paths as single-step - set a breakpoint at the
4320 signal return address and then, once hit, step off that
4323 fprintf_unfiltered (gdb_stdlog
,
4324 "infrun: signal arrived while stepping over "
4327 insert_hp_step_resume_breakpoint_at_frame (frame
);
4328 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4329 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4330 ecs
->event_thread
->control
.trap_expected
= 0;
4335 if (ecs
->event_thread
->control
.step_range_end
!= 0
4336 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4337 && (ecs
->event_thread
->control
.step_range_start
<= stop_pc
4338 && stop_pc
< ecs
->event_thread
->control
.step_range_end
)
4339 && frame_id_eq (get_stack_frame_id (frame
),
4340 ecs
->event_thread
->control
.step_stack_frame_id
)
4341 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4343 /* The inferior is about to take a signal that will take it
4344 out of the single step range. Set a breakpoint at the
4345 current PC (which is presumably where the signal handler
4346 will eventually return) and then allow the inferior to
4349 Note that this is only needed for a signal delivered
4350 while in the single-step range. Nested signals aren't a
4351 problem as they eventually all return. */
4353 fprintf_unfiltered (gdb_stdlog
,
4354 "infrun: signal may take us out of "
4355 "single-step range\n");
4357 insert_hp_step_resume_breakpoint_at_frame (frame
);
4358 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4359 ecs
->event_thread
->control
.trap_expected
= 0;
4364 /* Note: step_resume_breakpoint may be non-NULL. This occures
4365 when either there's a nested signal, or when there's a
4366 pending signal enabled just as the signal handler returns
4367 (leaving the inferior at the step-resume-breakpoint without
4368 actually executing it). Either way continue until the
4369 breakpoint is really hit. */
4373 /* Handle cases caused by hitting a breakpoint. */
4375 CORE_ADDR jmp_buf_pc
;
4376 struct bpstat_what what
;
4378 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4380 if (what
.call_dummy
)
4382 stop_stack_dummy
= what
.call_dummy
;
4385 /* If we hit an internal event that triggers symbol changes, the
4386 current frame will be invalidated within bpstat_what (e.g.,
4387 if we hit an internal solib event). Re-fetch it. */
4388 frame
= get_current_frame ();
4389 gdbarch
= get_frame_arch (frame
);
4391 switch (what
.main_action
)
4393 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4394 /* If we hit the breakpoint at longjmp while stepping, we
4395 install a momentary breakpoint at the target of the
4399 fprintf_unfiltered (gdb_stdlog
,
4400 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4402 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4404 if (what
.is_longjmp
)
4406 struct value
*arg_value
;
4408 /* If we set the longjmp breakpoint via a SystemTap
4409 probe, then use it to extract the arguments. The
4410 destination PC is the third argument to the
4412 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4414 jmp_buf_pc
= value_as_address (arg_value
);
4415 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4416 || !gdbarch_get_longjmp_target (gdbarch
,
4417 frame
, &jmp_buf_pc
))
4420 fprintf_unfiltered (gdb_stdlog
,
4421 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4422 "(!gdbarch_get_longjmp_target)\n");
4427 /* Insert a breakpoint at resume address. */
4428 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4431 check_exception_resume (ecs
, frame
);
4435 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4437 struct frame_info
*init_frame
;
4439 /* There are several cases to consider.
4441 1. The initiating frame no longer exists. In this case
4442 we must stop, because the exception or longjmp has gone
4445 2. The initiating frame exists, and is the same as the
4446 current frame. We stop, because the exception or
4447 longjmp has been caught.
4449 3. The initiating frame exists and is different from
4450 the current frame. This means the exception or longjmp
4451 has been caught beneath the initiating frame, so keep
4454 4. longjmp breakpoint has been placed just to protect
4455 against stale dummy frames and user is not interested
4456 in stopping around longjmps. */
4459 fprintf_unfiltered (gdb_stdlog
,
4460 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4462 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4464 delete_exception_resume_breakpoint (ecs
->event_thread
);
4466 if (what
.is_longjmp
)
4468 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
->num
);
4470 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
4478 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4482 struct frame_id current_id
4483 = get_frame_id (get_current_frame ());
4484 if (frame_id_eq (current_id
,
4485 ecs
->event_thread
->initiating_frame
))
4487 /* Case 2. Fall through. */
4497 /* For Cases 1 and 2, remove the step-resume breakpoint,
4499 delete_step_resume_breakpoint (ecs
->event_thread
);
4501 ecs
->event_thread
->control
.stop_step
= 1;
4502 print_end_stepping_range_reason ();
4503 stop_stepping (ecs
);
4507 case BPSTAT_WHAT_SINGLE
:
4509 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4510 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4511 /* Still need to check other stuff, at least the case where
4512 we are stepping and step out of the right range. */
4515 case BPSTAT_WHAT_STEP_RESUME
:
4517 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4519 delete_step_resume_breakpoint (ecs
->event_thread
);
4520 if (ecs
->event_thread
->control
.proceed_to_finish
4521 && execution_direction
== EXEC_REVERSE
)
4523 struct thread_info
*tp
= ecs
->event_thread
;
4525 /* We are finishing a function in reverse, and just hit
4526 the step-resume breakpoint at the start address of
4527 the function, and we're almost there -- just need to
4528 back up by one more single-step, which should take us
4529 back to the function call. */
4530 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4534 fill_in_stop_func (gdbarch
, ecs
);
4535 if (stop_pc
== ecs
->stop_func_start
4536 && execution_direction
== EXEC_REVERSE
)
4538 /* We are stepping over a function call in reverse, and
4539 just hit the step-resume breakpoint at the start
4540 address of the function. Go back to single-stepping,
4541 which should take us back to the function call. */
4542 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4548 case BPSTAT_WHAT_STOP_NOISY
:
4550 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4551 stop_print_frame
= 1;
4553 /* We are about to nuke the step_resume_breakpointt via the
4554 cleanup chain, so no need to worry about it here. */
4556 stop_stepping (ecs
);
4559 case BPSTAT_WHAT_STOP_SILENT
:
4561 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4562 stop_print_frame
= 0;
4564 /* We are about to nuke the step_resume_breakpoin via the
4565 cleanup chain, so no need to worry about it here. */
4567 stop_stepping (ecs
);
4570 case BPSTAT_WHAT_HP_STEP_RESUME
:
4572 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4574 delete_step_resume_breakpoint (ecs
->event_thread
);
4575 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4577 /* Back when the step-resume breakpoint was inserted, we
4578 were trying to single-step off a breakpoint. Go back
4580 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4581 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4587 case BPSTAT_WHAT_KEEP_CHECKING
:
4592 /* We come here if we hit a breakpoint but should not
4593 stop for it. Possibly we also were stepping
4594 and should stop for that. So fall through and
4595 test for stepping. But, if not stepping,
4598 /* In all-stop mode, if we're currently stepping but have stopped in
4599 some other thread, we need to switch back to the stepped thread. */
4602 struct thread_info
*tp
;
4604 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
4608 /* However, if the current thread is blocked on some internal
4609 breakpoint, and we simply need to step over that breakpoint
4610 to get it going again, do that first. */
4611 if ((ecs
->event_thread
->control
.trap_expected
4612 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
4613 || ecs
->event_thread
->stepping_over_breakpoint
)
4619 /* If the stepping thread exited, then don't try to switch
4620 back and resume it, which could fail in several different
4621 ways depending on the target. Instead, just keep going.
4623 We can find a stepping dead thread in the thread list in
4626 - The target supports thread exit events, and when the
4627 target tries to delete the thread from the thread list,
4628 inferior_ptid pointed at the exiting thread. In such
4629 case, calling delete_thread does not really remove the
4630 thread from the list; instead, the thread is left listed,
4631 with 'exited' state.
4633 - The target's debug interface does not support thread
4634 exit events, and so we have no idea whatsoever if the
4635 previously stepping thread is still alive. For that
4636 reason, we need to synchronously query the target
4638 if (is_exited (tp
->ptid
)
4639 || !target_thread_alive (tp
->ptid
))
4642 fprintf_unfiltered (gdb_stdlog
,
4643 "infrun: not switching back to "
4644 "stepped thread, it has vanished\n");
4646 delete_thread (tp
->ptid
);
4651 /* Otherwise, we no longer expect a trap in the current thread.
4652 Clear the trap_expected flag before switching back -- this is
4653 what keep_going would do as well, if we called it. */
4654 ecs
->event_thread
->control
.trap_expected
= 0;
4657 fprintf_unfiltered (gdb_stdlog
,
4658 "infrun: switching back to stepped thread\n");
4660 ecs
->event_thread
= tp
;
4661 ecs
->ptid
= tp
->ptid
;
4662 context_switch (ecs
->ptid
);
4668 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4671 fprintf_unfiltered (gdb_stdlog
,
4672 "infrun: step-resume breakpoint is inserted\n");
4674 /* Having a step-resume breakpoint overrides anything
4675 else having to do with stepping commands until
4676 that breakpoint is reached. */
4681 if (ecs
->event_thread
->control
.step_range_end
== 0)
4684 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4685 /* Likewise if we aren't even stepping. */
4690 /* Re-fetch current thread's frame in case the code above caused
4691 the frame cache to be re-initialized, making our FRAME variable
4692 a dangling pointer. */
4693 frame
= get_current_frame ();
4694 gdbarch
= get_frame_arch (frame
);
4695 fill_in_stop_func (gdbarch
, ecs
);
4697 /* If stepping through a line, keep going if still within it.
4699 Note that step_range_end is the address of the first instruction
4700 beyond the step range, and NOT the address of the last instruction
4703 Note also that during reverse execution, we may be stepping
4704 through a function epilogue and therefore must detect when
4705 the current-frame changes in the middle of a line. */
4707 if (stop_pc
>= ecs
->event_thread
->control
.step_range_start
4708 && stop_pc
< ecs
->event_thread
->control
.step_range_end
4709 && (execution_direction
!= EXEC_REVERSE
4710 || frame_id_eq (get_frame_id (frame
),
4711 ecs
->event_thread
->control
.step_frame_id
)))
4715 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4716 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4717 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4719 /* When stepping backward, stop at beginning of line range
4720 (unless it's the function entry point, in which case
4721 keep going back to the call point). */
4722 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4723 && stop_pc
!= ecs
->stop_func_start
4724 && execution_direction
== EXEC_REVERSE
)
4726 ecs
->event_thread
->control
.stop_step
= 1;
4727 print_end_stepping_range_reason ();
4728 stop_stepping (ecs
);
4736 /* We stepped out of the stepping range. */
4738 /* If we are stepping at the source level and entered the runtime
4739 loader dynamic symbol resolution code...
4741 EXEC_FORWARD: we keep on single stepping until we exit the run
4742 time loader code and reach the callee's address.
4744 EXEC_REVERSE: we've already executed the callee (backward), and
4745 the runtime loader code is handled just like any other
4746 undebuggable function call. Now we need only keep stepping
4747 backward through the trampoline code, and that's handled further
4748 down, so there is nothing for us to do here. */
4750 if (execution_direction
!= EXEC_REVERSE
4751 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4752 && in_solib_dynsym_resolve_code (stop_pc
))
4754 CORE_ADDR pc_after_resolver
=
4755 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
4758 fprintf_unfiltered (gdb_stdlog
,
4759 "infrun: stepped into dynsym resolve code\n");
4761 if (pc_after_resolver
)
4763 /* Set up a step-resume breakpoint at the address
4764 indicated by SKIP_SOLIB_RESOLVER. */
4765 struct symtab_and_line sr_sal
;
4768 sr_sal
.pc
= pc_after_resolver
;
4769 sr_sal
.pspace
= get_frame_program_space (frame
);
4771 insert_step_resume_breakpoint_at_sal (gdbarch
,
4772 sr_sal
, null_frame_id
);
4779 if (ecs
->event_thread
->control
.step_range_end
!= 1
4780 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4781 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4782 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
4785 fprintf_unfiltered (gdb_stdlog
,
4786 "infrun: stepped into signal trampoline\n");
4787 /* The inferior, while doing a "step" or "next", has ended up in
4788 a signal trampoline (either by a signal being delivered or by
4789 the signal handler returning). Just single-step until the
4790 inferior leaves the trampoline (either by calling the handler
4796 /* If we're in the return path from a shared library trampoline,
4797 we want to proceed through the trampoline when stepping. */
4798 /* macro/2012-04-25: This needs to come before the subroutine
4799 call check below as on some targets return trampolines look
4800 like subroutine calls (MIPS16 return thunks). */
4801 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4802 stop_pc
, ecs
->stop_func_name
)
4803 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
4805 /* Determine where this trampoline returns. */
4806 CORE_ADDR real_stop_pc
;
4808 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4811 fprintf_unfiltered (gdb_stdlog
,
4812 "infrun: stepped into solib return tramp\n");
4814 /* Only proceed through if we know where it's going. */
4817 /* And put the step-breakpoint there and go until there. */
4818 struct symtab_and_line sr_sal
;
4820 init_sal (&sr_sal
); /* initialize to zeroes */
4821 sr_sal
.pc
= real_stop_pc
;
4822 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4823 sr_sal
.pspace
= get_frame_program_space (frame
);
4825 /* Do not specify what the fp should be when we stop since
4826 on some machines the prologue is where the new fp value
4828 insert_step_resume_breakpoint_at_sal (gdbarch
,
4829 sr_sal
, null_frame_id
);
4831 /* Restart without fiddling with the step ranges or
4838 /* Check for subroutine calls. The check for the current frame
4839 equalling the step ID is not necessary - the check of the
4840 previous frame's ID is sufficient - but it is a common case and
4841 cheaper than checking the previous frame's ID.
4843 NOTE: frame_id_eq will never report two invalid frame IDs as
4844 being equal, so to get into this block, both the current and
4845 previous frame must have valid frame IDs. */
4846 /* The outer_frame_id check is a heuristic to detect stepping
4847 through startup code. If we step over an instruction which
4848 sets the stack pointer from an invalid value to a valid value,
4849 we may detect that as a subroutine call from the mythical
4850 "outermost" function. This could be fixed by marking
4851 outermost frames as !stack_p,code_p,special_p. Then the
4852 initial outermost frame, before sp was valid, would
4853 have code_addr == &_start. See the comment in frame_id_eq
4855 if (!frame_id_eq (get_stack_frame_id (frame
),
4856 ecs
->event_thread
->control
.step_stack_frame_id
)
4857 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4858 ecs
->event_thread
->control
.step_stack_frame_id
)
4859 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
4861 || step_start_function
!= find_pc_function (stop_pc
))))
4863 CORE_ADDR real_stop_pc
;
4866 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
4868 if ((ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
4869 || ((ecs
->event_thread
->control
.step_range_end
== 1)
4870 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
4871 ecs
->stop_func_start
)))
4873 /* I presume that step_over_calls is only 0 when we're
4874 supposed to be stepping at the assembly language level
4875 ("stepi"). Just stop. */
4876 /* Also, maybe we just did a "nexti" inside a prolog, so we
4877 thought it was a subroutine call but it was not. Stop as
4879 /* And this works the same backward as frontward. MVS */
4880 ecs
->event_thread
->control
.stop_step
= 1;
4881 print_end_stepping_range_reason ();
4882 stop_stepping (ecs
);
4886 /* Reverse stepping through solib trampolines. */
4888 if (execution_direction
== EXEC_REVERSE
4889 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
4890 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4891 || (ecs
->stop_func_start
== 0
4892 && in_solib_dynsym_resolve_code (stop_pc
))))
4894 /* Any solib trampoline code can be handled in reverse
4895 by simply continuing to single-step. We have already
4896 executed the solib function (backwards), and a few
4897 steps will take us back through the trampoline to the
4903 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4905 /* We're doing a "next".
4907 Normal (forward) execution: set a breakpoint at the
4908 callee's return address (the address at which the caller
4911 Reverse (backward) execution. set the step-resume
4912 breakpoint at the start of the function that we just
4913 stepped into (backwards), and continue to there. When we
4914 get there, we'll need to single-step back to the caller. */
4916 if (execution_direction
== EXEC_REVERSE
)
4918 /* If we're already at the start of the function, we've either
4919 just stepped backward into a single instruction function,
4920 or stepped back out of a signal handler to the first instruction
4921 of the function. Just keep going, which will single-step back
4923 if (ecs
->stop_func_start
!= stop_pc
)
4925 struct symtab_and_line sr_sal
;
4927 /* Normal function call return (static or dynamic). */
4929 sr_sal
.pc
= ecs
->stop_func_start
;
4930 sr_sal
.pspace
= get_frame_program_space (frame
);
4931 insert_step_resume_breakpoint_at_sal (gdbarch
,
4932 sr_sal
, null_frame_id
);
4936 insert_step_resume_breakpoint_at_caller (frame
);
4942 /* If we are in a function call trampoline (a stub between the
4943 calling routine and the real function), locate the real
4944 function. That's what tells us (a) whether we want to step
4945 into it at all, and (b) what prologue we want to run to the
4946 end of, if we do step into it. */
4947 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
4948 if (real_stop_pc
== 0)
4949 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4950 if (real_stop_pc
!= 0)
4951 ecs
->stop_func_start
= real_stop_pc
;
4953 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
4955 struct symtab_and_line sr_sal
;
4958 sr_sal
.pc
= ecs
->stop_func_start
;
4959 sr_sal
.pspace
= get_frame_program_space (frame
);
4961 insert_step_resume_breakpoint_at_sal (gdbarch
,
4962 sr_sal
, null_frame_id
);
4967 /* If we have line number information for the function we are
4968 thinking of stepping into and the function isn't on the skip
4971 If there are several symtabs at that PC (e.g. with include
4972 files), just want to know whether *any* of them have line
4973 numbers. find_pc_line handles this. */
4975 struct symtab_and_line tmp_sal
;
4977 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4978 if (tmp_sal
.line
!= 0
4979 && !function_pc_is_marked_for_skip (ecs
->stop_func_start
))
4981 if (execution_direction
== EXEC_REVERSE
)
4982 handle_step_into_function_backward (gdbarch
, ecs
);
4984 handle_step_into_function (gdbarch
, ecs
);
4989 /* If we have no line number and the step-stop-if-no-debug is
4990 set, we stop the step so that the user has a chance to switch
4991 in assembly mode. */
4992 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4993 && step_stop_if_no_debug
)
4995 ecs
->event_thread
->control
.stop_step
= 1;
4996 print_end_stepping_range_reason ();
4997 stop_stepping (ecs
);
5001 if (execution_direction
== EXEC_REVERSE
)
5003 /* If we're already at the start of the function, we've either just
5004 stepped backward into a single instruction function without line
5005 number info, or stepped back out of a signal handler to the first
5006 instruction of the function without line number info. Just keep
5007 going, which will single-step back to the caller. */
5008 if (ecs
->stop_func_start
!= stop_pc
)
5010 /* Set a breakpoint at callee's start address.
5011 From there we can step once and be back in the caller. */
5012 struct symtab_and_line sr_sal
;
5015 sr_sal
.pc
= ecs
->stop_func_start
;
5016 sr_sal
.pspace
= get_frame_program_space (frame
);
5017 insert_step_resume_breakpoint_at_sal (gdbarch
,
5018 sr_sal
, null_frame_id
);
5022 /* Set a breakpoint at callee's return address (the address
5023 at which the caller will resume). */
5024 insert_step_resume_breakpoint_at_caller (frame
);
5030 /* Reverse stepping through solib trampolines. */
5032 if (execution_direction
== EXEC_REVERSE
5033 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5035 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5036 || (ecs
->stop_func_start
== 0
5037 && in_solib_dynsym_resolve_code (stop_pc
)))
5039 /* Any solib trampoline code can be handled in reverse
5040 by simply continuing to single-step. We have already
5041 executed the solib function (backwards), and a few
5042 steps will take us back through the trampoline to the
5047 else if (in_solib_dynsym_resolve_code (stop_pc
))
5049 /* Stepped backward into the solib dynsym resolver.
5050 Set a breakpoint at its start and continue, then
5051 one more step will take us out. */
5052 struct symtab_and_line sr_sal
;
5055 sr_sal
.pc
= ecs
->stop_func_start
;
5056 sr_sal
.pspace
= get_frame_program_space (frame
);
5057 insert_step_resume_breakpoint_at_sal (gdbarch
,
5058 sr_sal
, null_frame_id
);
5064 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5066 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5067 the trampoline processing logic, however, there are some trampolines
5068 that have no names, so we should do trampoline handling first. */
5069 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5070 && ecs
->stop_func_name
== NULL
5071 && stop_pc_sal
.line
== 0)
5074 fprintf_unfiltered (gdb_stdlog
,
5075 "infrun: stepped into undebuggable function\n");
5077 /* The inferior just stepped into, or returned to, an
5078 undebuggable function (where there is no debugging information
5079 and no line number corresponding to the address where the
5080 inferior stopped). Since we want to skip this kind of code,
5081 we keep going until the inferior returns from this
5082 function - unless the user has asked us not to (via
5083 set step-mode) or we no longer know how to get back
5084 to the call site. */
5085 if (step_stop_if_no_debug
5086 || !frame_id_p (frame_unwind_caller_id (frame
)))
5088 /* If we have no line number and the step-stop-if-no-debug
5089 is set, we stop the step so that the user has a chance to
5090 switch in assembly mode. */
5091 ecs
->event_thread
->control
.stop_step
= 1;
5092 print_end_stepping_range_reason ();
5093 stop_stepping (ecs
);
5098 /* Set a breakpoint at callee's return address (the address
5099 at which the caller will resume). */
5100 insert_step_resume_breakpoint_at_caller (frame
);
5106 if (ecs
->event_thread
->control
.step_range_end
== 1)
5108 /* It is stepi or nexti. We always want to stop stepping after
5111 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5112 ecs
->event_thread
->control
.stop_step
= 1;
5113 print_end_stepping_range_reason ();
5114 stop_stepping (ecs
);
5118 if (stop_pc_sal
.line
== 0)
5120 /* We have no line number information. That means to stop
5121 stepping (does this always happen right after one instruction,
5122 when we do "s" in a function with no line numbers,
5123 or can this happen as a result of a return or longjmp?). */
5125 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5126 ecs
->event_thread
->control
.stop_step
= 1;
5127 print_end_stepping_range_reason ();
5128 stop_stepping (ecs
);
5132 /* Look for "calls" to inlined functions, part one. If the inline
5133 frame machinery detected some skipped call sites, we have entered
5134 a new inline function. */
5136 if (frame_id_eq (get_frame_id (get_current_frame ()),
5137 ecs
->event_thread
->control
.step_frame_id
)
5138 && inline_skipped_frames (ecs
->ptid
))
5140 struct symtab_and_line call_sal
;
5143 fprintf_unfiltered (gdb_stdlog
,
5144 "infrun: stepped into inlined function\n");
5146 find_frame_sal (get_current_frame (), &call_sal
);
5148 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5150 /* For "step", we're going to stop. But if the call site
5151 for this inlined function is on the same source line as
5152 we were previously stepping, go down into the function
5153 first. Otherwise stop at the call site. */
5155 if (call_sal
.line
== ecs
->event_thread
->current_line
5156 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5157 step_into_inline_frame (ecs
->ptid
);
5159 ecs
->event_thread
->control
.stop_step
= 1;
5160 print_end_stepping_range_reason ();
5161 stop_stepping (ecs
);
5166 /* For "next", we should stop at the call site if it is on a
5167 different source line. Otherwise continue through the
5168 inlined function. */
5169 if (call_sal
.line
== ecs
->event_thread
->current_line
5170 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5174 ecs
->event_thread
->control
.stop_step
= 1;
5175 print_end_stepping_range_reason ();
5176 stop_stepping (ecs
);
5182 /* Look for "calls" to inlined functions, part two. If we are still
5183 in the same real function we were stepping through, but we have
5184 to go further up to find the exact frame ID, we are stepping
5185 through a more inlined call beyond its call site. */
5187 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5188 && !frame_id_eq (get_frame_id (get_current_frame ()),
5189 ecs
->event_thread
->control
.step_frame_id
)
5190 && stepped_in_from (get_current_frame (),
5191 ecs
->event_thread
->control
.step_frame_id
))
5194 fprintf_unfiltered (gdb_stdlog
,
5195 "infrun: stepping through inlined function\n");
5197 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5201 ecs
->event_thread
->control
.stop_step
= 1;
5202 print_end_stepping_range_reason ();
5203 stop_stepping (ecs
);
5208 if ((stop_pc
== stop_pc_sal
.pc
)
5209 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5210 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5212 /* We are at the start of a different line. So stop. Note that
5213 we don't stop if we step into the middle of a different line.
5214 That is said to make things like for (;;) statements work
5217 fprintf_unfiltered (gdb_stdlog
,
5218 "infrun: stepped to a different line\n");
5219 ecs
->event_thread
->control
.stop_step
= 1;
5220 print_end_stepping_range_reason ();
5221 stop_stepping (ecs
);
5225 /* We aren't done stepping.
5227 Optimize by setting the stepping range to the line.
5228 (We might not be in the original line, but if we entered a
5229 new line in mid-statement, we continue stepping. This makes
5230 things like for(;;) statements work better.) */
5232 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5233 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5234 set_step_info (frame
, stop_pc_sal
);
5237 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5241 /* Is thread TP in the middle of single-stepping? */
5244 currently_stepping (struct thread_info
*tp
)
5246 return ((tp
->control
.step_range_end
5247 && tp
->control
.step_resume_breakpoint
== NULL
)
5248 || tp
->control
.trap_expected
5249 || bpstat_should_step ());
5252 /* Returns true if any thread *but* the one passed in "data" is in the
5253 middle of stepping or of handling a "next". */
5256 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
5261 return (tp
->control
.step_range_end
5262 || tp
->control
.trap_expected
);
5265 /* Inferior has stepped into a subroutine call with source code that
5266 we should not step over. Do step to the first line of code in
5270 handle_step_into_function (struct gdbarch
*gdbarch
,
5271 struct execution_control_state
*ecs
)
5274 struct symtab_and_line stop_func_sal
, sr_sal
;
5276 fill_in_stop_func (gdbarch
, ecs
);
5278 s
= find_pc_symtab (stop_pc
);
5279 if (s
&& s
->language
!= language_asm
)
5280 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5281 ecs
->stop_func_start
);
5283 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5284 /* Use the step_resume_break to step until the end of the prologue,
5285 even if that involves jumps (as it seems to on the vax under
5287 /* If the prologue ends in the middle of a source line, continue to
5288 the end of that source line (if it is still within the function).
5289 Otherwise, just go to end of prologue. */
5290 if (stop_func_sal
.end
5291 && stop_func_sal
.pc
!= ecs
->stop_func_start
5292 && stop_func_sal
.end
< ecs
->stop_func_end
)
5293 ecs
->stop_func_start
= stop_func_sal
.end
;
5295 /* Architectures which require breakpoint adjustment might not be able
5296 to place a breakpoint at the computed address. If so, the test
5297 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5298 ecs->stop_func_start to an address at which a breakpoint may be
5299 legitimately placed.
5301 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5302 made, GDB will enter an infinite loop when stepping through
5303 optimized code consisting of VLIW instructions which contain
5304 subinstructions corresponding to different source lines. On
5305 FR-V, it's not permitted to place a breakpoint on any but the
5306 first subinstruction of a VLIW instruction. When a breakpoint is
5307 set, GDB will adjust the breakpoint address to the beginning of
5308 the VLIW instruction. Thus, we need to make the corresponding
5309 adjustment here when computing the stop address. */
5311 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5313 ecs
->stop_func_start
5314 = gdbarch_adjust_breakpoint_address (gdbarch
,
5315 ecs
->stop_func_start
);
5318 if (ecs
->stop_func_start
== stop_pc
)
5320 /* We are already there: stop now. */
5321 ecs
->event_thread
->control
.stop_step
= 1;
5322 print_end_stepping_range_reason ();
5323 stop_stepping (ecs
);
5328 /* Put the step-breakpoint there and go until there. */
5329 init_sal (&sr_sal
); /* initialize to zeroes */
5330 sr_sal
.pc
= ecs
->stop_func_start
;
5331 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5332 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5334 /* Do not specify what the fp should be when we stop since on
5335 some machines the prologue is where the new fp value is
5337 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5339 /* And make sure stepping stops right away then. */
5340 ecs
->event_thread
->control
.step_range_end
5341 = ecs
->event_thread
->control
.step_range_start
;
5346 /* Inferior has stepped backward into a subroutine call with source
5347 code that we should not step over. Do step to the beginning of the
5348 last line of code in it. */
5351 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5352 struct execution_control_state
*ecs
)
5355 struct symtab_and_line stop_func_sal
;
5357 fill_in_stop_func (gdbarch
, ecs
);
5359 s
= find_pc_symtab (stop_pc
);
5360 if (s
&& s
->language
!= language_asm
)
5361 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5362 ecs
->stop_func_start
);
5364 stop_func_sal
= find_pc_line (stop_pc
, 0);
5366 /* OK, we're just going to keep stepping here. */
5367 if (stop_func_sal
.pc
== stop_pc
)
5369 /* We're there already. Just stop stepping now. */
5370 ecs
->event_thread
->control
.stop_step
= 1;
5371 print_end_stepping_range_reason ();
5372 stop_stepping (ecs
);
5376 /* Else just reset the step range and keep going.
5377 No step-resume breakpoint, they don't work for
5378 epilogues, which can have multiple entry paths. */
5379 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5380 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5386 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5387 This is used to both functions and to skip over code. */
5390 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5391 struct symtab_and_line sr_sal
,
5392 struct frame_id sr_id
,
5393 enum bptype sr_type
)
5395 /* There should never be more than one step-resume or longjmp-resume
5396 breakpoint per thread, so we should never be setting a new
5397 step_resume_breakpoint when one is already active. */
5398 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5399 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5402 fprintf_unfiltered (gdb_stdlog
,
5403 "infrun: inserting step-resume breakpoint at %s\n",
5404 paddress (gdbarch
, sr_sal
.pc
));
5406 inferior_thread ()->control
.step_resume_breakpoint
5407 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5411 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5412 struct symtab_and_line sr_sal
,
5413 struct frame_id sr_id
)
5415 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5420 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5421 This is used to skip a potential signal handler.
5423 This is called with the interrupted function's frame. The signal
5424 handler, when it returns, will resume the interrupted function at
5428 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5430 struct symtab_and_line sr_sal
;
5431 struct gdbarch
*gdbarch
;
5433 gdb_assert (return_frame
!= NULL
);
5434 init_sal (&sr_sal
); /* initialize to zeros */
5436 gdbarch
= get_frame_arch (return_frame
);
5437 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5438 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5439 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5441 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5442 get_stack_frame_id (return_frame
),
5446 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5447 is used to skip a function after stepping into it (for "next" or if
5448 the called function has no debugging information).
5450 The current function has almost always been reached by single
5451 stepping a call or return instruction. NEXT_FRAME belongs to the
5452 current function, and the breakpoint will be set at the caller's
5455 This is a separate function rather than reusing
5456 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5457 get_prev_frame, which may stop prematurely (see the implementation
5458 of frame_unwind_caller_id for an example). */
5461 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5463 struct symtab_and_line sr_sal
;
5464 struct gdbarch
*gdbarch
;
5466 /* We shouldn't have gotten here if we don't know where the call site
5468 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5470 init_sal (&sr_sal
); /* initialize to zeros */
5472 gdbarch
= frame_unwind_caller_arch (next_frame
);
5473 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5474 frame_unwind_caller_pc (next_frame
));
5475 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5476 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5478 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5479 frame_unwind_caller_id (next_frame
));
5482 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5483 new breakpoint at the target of a jmp_buf. The handling of
5484 longjmp-resume uses the same mechanisms used for handling
5485 "step-resume" breakpoints. */
5488 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5490 /* There should never be more than one longjmp-resume breakpoint per
5491 thread, so we should never be setting a new
5492 longjmp_resume_breakpoint when one is already active. */
5493 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
5496 fprintf_unfiltered (gdb_stdlog
,
5497 "infrun: inserting longjmp-resume breakpoint at %s\n",
5498 paddress (gdbarch
, pc
));
5500 inferior_thread ()->control
.exception_resume_breakpoint
=
5501 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5504 /* Insert an exception resume breakpoint. TP is the thread throwing
5505 the exception. The block B is the block of the unwinder debug hook
5506 function. FRAME is the frame corresponding to the call to this
5507 function. SYM is the symbol of the function argument holding the
5508 target PC of the exception. */
5511 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5513 struct frame_info
*frame
,
5516 volatile struct gdb_exception e
;
5518 /* We want to ignore errors here. */
5519 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5521 struct symbol
*vsym
;
5522 struct value
*value
;
5524 struct breakpoint
*bp
;
5526 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5527 value
= read_var_value (vsym
, frame
);
5528 /* If the value was optimized out, revert to the old behavior. */
5529 if (! value_optimized_out (value
))
5531 handler
= value_as_address (value
);
5534 fprintf_unfiltered (gdb_stdlog
,
5535 "infrun: exception resume at %lx\n",
5536 (unsigned long) handler
);
5538 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5539 handler
, bp_exception_resume
);
5541 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5544 bp
->thread
= tp
->num
;
5545 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5550 /* A helper for check_exception_resume that sets an
5551 exception-breakpoint based on a SystemTap probe. */
5554 insert_exception_resume_from_probe (struct thread_info
*tp
,
5555 const struct probe
*probe
,
5556 struct frame_info
*frame
)
5558 struct value
*arg_value
;
5560 struct breakpoint
*bp
;
5562 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
5566 handler
= value_as_address (arg_value
);
5569 fprintf_unfiltered (gdb_stdlog
,
5570 "infrun: exception resume at %s\n",
5571 paddress (get_objfile_arch (probe
->objfile
),
5574 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5575 handler
, bp_exception_resume
);
5576 bp
->thread
= tp
->num
;
5577 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5580 /* This is called when an exception has been intercepted. Check to
5581 see whether the exception's destination is of interest, and if so,
5582 set an exception resume breakpoint there. */
5585 check_exception_resume (struct execution_control_state
*ecs
,
5586 struct frame_info
*frame
)
5588 volatile struct gdb_exception e
;
5589 const struct probe
*probe
;
5590 struct symbol
*func
;
5592 /* First see if this exception unwinding breakpoint was set via a
5593 SystemTap probe point. If so, the probe has two arguments: the
5594 CFA and the HANDLER. We ignore the CFA, extract the handler, and
5595 set a breakpoint there. */
5596 probe
= find_probe_by_pc (get_frame_pc (frame
));
5599 insert_exception_resume_from_probe (ecs
->event_thread
, probe
, frame
);
5603 func
= get_frame_function (frame
);
5607 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5610 struct block_iterator iter
;
5614 /* The exception breakpoint is a thread-specific breakpoint on
5615 the unwinder's debug hook, declared as:
5617 void _Unwind_DebugHook (void *cfa, void *handler);
5619 The CFA argument indicates the frame to which control is
5620 about to be transferred. HANDLER is the destination PC.
5622 We ignore the CFA and set a temporary breakpoint at HANDLER.
5623 This is not extremely efficient but it avoids issues in gdb
5624 with computing the DWARF CFA, and it also works even in weird
5625 cases such as throwing an exception from inside a signal
5628 b
= SYMBOL_BLOCK_VALUE (func
);
5629 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
5631 if (!SYMBOL_IS_ARGUMENT (sym
))
5638 insert_exception_resume_breakpoint (ecs
->event_thread
,
5647 stop_stepping (struct execution_control_state
*ecs
)
5650 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
5652 /* Let callers know we don't want to wait for the inferior anymore. */
5653 ecs
->wait_some_more
= 0;
5656 /* This function handles various cases where we need to continue
5657 waiting for the inferior. */
5658 /* (Used to be the keep_going: label in the old wait_for_inferior). */
5661 keep_going (struct execution_control_state
*ecs
)
5663 /* Make sure normal_stop is called if we get a QUIT handled before
5665 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
5667 /* Save the pc before execution, to compare with pc after stop. */
5668 ecs
->event_thread
->prev_pc
5669 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5671 /* If we did not do break;, it means we should keep running the
5672 inferior and not return to debugger. */
5674 if (ecs
->event_thread
->control
.trap_expected
5675 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5677 /* We took a signal (which we are supposed to pass through to
5678 the inferior, else we'd not get here) and we haven't yet
5679 gotten our trap. Simply continue. */
5681 discard_cleanups (old_cleanups
);
5682 resume (currently_stepping (ecs
->event_thread
),
5683 ecs
->event_thread
->suspend
.stop_signal
);
5687 /* Either the trap was not expected, but we are continuing
5688 anyway (the user asked that this signal be passed to the
5691 The signal was SIGTRAP, e.g. it was our signal, but we
5692 decided we should resume from it.
5694 We're going to run this baby now!
5696 Note that insert_breakpoints won't try to re-insert
5697 already inserted breakpoints. Therefore, we don't
5698 care if breakpoints were already inserted, or not. */
5700 if (ecs
->event_thread
->stepping_over_breakpoint
)
5702 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
5704 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
5705 /* Since we can't do a displaced step, we have to remove
5706 the breakpoint while we step it. To keep things
5707 simple, we remove them all. */
5708 remove_breakpoints ();
5712 volatile struct gdb_exception e
;
5714 /* Stop stepping when inserting breakpoints
5716 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5718 insert_breakpoints ();
5722 exception_print (gdb_stderr
, e
);
5723 stop_stepping (ecs
);
5728 ecs
->event_thread
->control
.trap_expected
5729 = ecs
->event_thread
->stepping_over_breakpoint
;
5731 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
5732 specifies that such a signal should be delivered to the
5735 Typically, this would occure when a user is debugging a
5736 target monitor on a simulator: the target monitor sets a
5737 breakpoint; the simulator encounters this break-point and
5738 halts the simulation handing control to GDB; GDB, noteing
5739 that the break-point isn't valid, returns control back to the
5740 simulator; the simulator then delivers the hardware
5741 equivalent of a SIGNAL_TRAP to the program being debugged. */
5743 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5744 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5745 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5747 discard_cleanups (old_cleanups
);
5748 resume (currently_stepping (ecs
->event_thread
),
5749 ecs
->event_thread
->suspend
.stop_signal
);
5752 prepare_to_wait (ecs
);
5755 /* This function normally comes after a resume, before
5756 handle_inferior_event exits. It takes care of any last bits of
5757 housekeeping, and sets the all-important wait_some_more flag. */
5760 prepare_to_wait (struct execution_control_state
*ecs
)
5763 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
5765 /* This is the old end of the while loop. Let everybody know we
5766 want to wait for the inferior some more and get called again
5768 ecs
->wait_some_more
= 1;
5771 /* Several print_*_reason functions to print why the inferior has stopped.
5772 We always print something when the inferior exits, or receives a signal.
5773 The rest of the cases are dealt with later on in normal_stop and
5774 print_it_typical. Ideally there should be a call to one of these
5775 print_*_reason functions functions from handle_inferior_event each time
5776 stop_stepping is called. */
5778 /* Print why the inferior has stopped.
5779 We are done with a step/next/si/ni command, print why the inferior has
5780 stopped. For now print nothing. Print a message only if not in the middle
5781 of doing a "step n" operation for n > 1. */
5784 print_end_stepping_range_reason (void)
5786 if ((!inferior_thread ()->step_multi
5787 || !inferior_thread ()->control
.stop_step
)
5788 && ui_out_is_mi_like_p (current_uiout
))
5789 ui_out_field_string (current_uiout
, "reason",
5790 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
5793 /* The inferior was terminated by a signal, print why it stopped. */
5796 print_signal_exited_reason (enum gdb_signal siggnal
)
5798 struct ui_out
*uiout
= current_uiout
;
5800 annotate_signalled ();
5801 if (ui_out_is_mi_like_p (uiout
))
5803 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
5804 ui_out_text (uiout
, "\nProgram terminated with signal ");
5805 annotate_signal_name ();
5806 ui_out_field_string (uiout
, "signal-name",
5807 gdb_signal_to_name (siggnal
));
5808 annotate_signal_name_end ();
5809 ui_out_text (uiout
, ", ");
5810 annotate_signal_string ();
5811 ui_out_field_string (uiout
, "signal-meaning",
5812 gdb_signal_to_string (siggnal
));
5813 annotate_signal_string_end ();
5814 ui_out_text (uiout
, ".\n");
5815 ui_out_text (uiout
, "The program no longer exists.\n");
5818 /* The inferior program is finished, print why it stopped. */
5821 print_exited_reason (int exitstatus
)
5823 struct inferior
*inf
= current_inferior ();
5824 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
5825 struct ui_out
*uiout
= current_uiout
;
5827 annotate_exited (exitstatus
);
5830 if (ui_out_is_mi_like_p (uiout
))
5831 ui_out_field_string (uiout
, "reason",
5832 async_reason_lookup (EXEC_ASYNC_EXITED
));
5833 ui_out_text (uiout
, "[Inferior ");
5834 ui_out_text (uiout
, plongest (inf
->num
));
5835 ui_out_text (uiout
, " (");
5836 ui_out_text (uiout
, pidstr
);
5837 ui_out_text (uiout
, ") exited with code ");
5838 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
5839 ui_out_text (uiout
, "]\n");
5843 if (ui_out_is_mi_like_p (uiout
))
5845 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
5846 ui_out_text (uiout
, "[Inferior ");
5847 ui_out_text (uiout
, plongest (inf
->num
));
5848 ui_out_text (uiout
, " (");
5849 ui_out_text (uiout
, pidstr
);
5850 ui_out_text (uiout
, ") exited normally]\n");
5852 /* Support the --return-child-result option. */
5853 return_child_result_value
= exitstatus
;
5856 /* Signal received, print why the inferior has stopped. The signal table
5857 tells us to print about it. */
5860 print_signal_received_reason (enum gdb_signal siggnal
)
5862 struct ui_out
*uiout
= current_uiout
;
5866 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
5868 struct thread_info
*t
= inferior_thread ();
5870 ui_out_text (uiout
, "\n[");
5871 ui_out_field_string (uiout
, "thread-name",
5872 target_pid_to_str (t
->ptid
));
5873 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
5874 ui_out_text (uiout
, " stopped");
5878 ui_out_text (uiout
, "\nProgram received signal ");
5879 annotate_signal_name ();
5880 if (ui_out_is_mi_like_p (uiout
))
5882 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
5883 ui_out_field_string (uiout
, "signal-name",
5884 gdb_signal_to_name (siggnal
));
5885 annotate_signal_name_end ();
5886 ui_out_text (uiout
, ", ");
5887 annotate_signal_string ();
5888 ui_out_field_string (uiout
, "signal-meaning",
5889 gdb_signal_to_string (siggnal
));
5890 annotate_signal_string_end ();
5892 ui_out_text (uiout
, ".\n");
5895 /* Reverse execution: target ran out of history info, print why the inferior
5899 print_no_history_reason (void)
5901 ui_out_text (current_uiout
, "\nNo more reverse-execution history.\n");
5904 /* Here to return control to GDB when the inferior stops for real.
5905 Print appropriate messages, remove breakpoints, give terminal our modes.
5907 STOP_PRINT_FRAME nonzero means print the executing frame
5908 (pc, function, args, file, line number and line text).
5909 BREAKPOINTS_FAILED nonzero means stop was due to error
5910 attempting to insert breakpoints. */
5915 struct target_waitstatus last
;
5917 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
5919 get_last_target_status (&last_ptid
, &last
);
5921 /* If an exception is thrown from this point on, make sure to
5922 propagate GDB's knowledge of the executing state to the
5923 frontend/user running state. A QUIT is an easy exception to see
5924 here, so do this before any filtered output. */
5926 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
5927 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
5928 && last
.kind
!= TARGET_WAITKIND_EXITED
5929 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
5930 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
5932 /* In non-stop mode, we don't want GDB to switch threads behind the
5933 user's back, to avoid races where the user is typing a command to
5934 apply to thread x, but GDB switches to thread y before the user
5935 finishes entering the command. */
5937 /* As with the notification of thread events, we want to delay
5938 notifying the user that we've switched thread context until
5939 the inferior actually stops.
5941 There's no point in saying anything if the inferior has exited.
5942 Note that SIGNALLED here means "exited with a signal", not
5943 "received a signal". */
5945 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
5946 && target_has_execution
5947 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5948 && last
.kind
!= TARGET_WAITKIND_EXITED
5949 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
5951 target_terminal_ours_for_output ();
5952 printf_filtered (_("[Switching to %s]\n"),
5953 target_pid_to_str (inferior_ptid
));
5954 annotate_thread_changed ();
5955 previous_inferior_ptid
= inferior_ptid
;
5958 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
5960 gdb_assert (sync_execution
|| !target_can_async_p ());
5962 target_terminal_ours_for_output ();
5963 printf_filtered (_("No unwaited-for children left.\n"));
5966 if (!breakpoints_always_inserted_mode () && target_has_execution
)
5968 if (remove_breakpoints ())
5970 target_terminal_ours_for_output ();
5971 printf_filtered (_("Cannot remove breakpoints because "
5972 "program is no longer writable.\nFurther "
5973 "execution is probably impossible.\n"));
5977 /* If an auto-display called a function and that got a signal,
5978 delete that auto-display to avoid an infinite recursion. */
5980 if (stopped_by_random_signal
)
5981 disable_current_display ();
5983 /* Don't print a message if in the middle of doing a "step n"
5984 operation for n > 1 */
5985 if (target_has_execution
5986 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5987 && last
.kind
!= TARGET_WAITKIND_EXITED
5988 && inferior_thread ()->step_multi
5989 && inferior_thread ()->control
.stop_step
)
5992 target_terminal_ours ();
5993 async_enable_stdin ();
5995 /* Set the current source location. This will also happen if we
5996 display the frame below, but the current SAL will be incorrect
5997 during a user hook-stop function. */
5998 if (has_stack_frames () && !stop_stack_dummy
)
5999 set_current_sal_from_frame (get_current_frame (), 1);
6001 /* Let the user/frontend see the threads as stopped. */
6002 do_cleanups (old_chain
);
6004 /* Look up the hook_stop and run it (CLI internally handles problem
6005 of stop_command's pre-hook not existing). */
6007 catch_errors (hook_stop_stub
, stop_command
,
6008 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
6010 if (!has_stack_frames ())
6013 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
6014 || last
.kind
== TARGET_WAITKIND_EXITED
)
6017 /* Select innermost stack frame - i.e., current frame is frame 0,
6018 and current location is based on that.
6019 Don't do this on return from a stack dummy routine,
6020 or if the program has exited. */
6022 if (!stop_stack_dummy
)
6024 select_frame (get_current_frame ());
6026 /* Print current location without a level number, if
6027 we have changed functions or hit a breakpoint.
6028 Print source line if we have one.
6029 bpstat_print() contains the logic deciding in detail
6030 what to print, based on the event(s) that just occurred. */
6032 /* If --batch-silent is enabled then there's no need to print the current
6033 source location, and to try risks causing an error message about
6034 missing source files. */
6035 if (stop_print_frame
&& !batch_silent
)
6039 int do_frame_printing
= 1;
6040 struct thread_info
*tp
= inferior_thread ();
6042 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, last
.kind
);
6046 /* FIXME: cagney/2002-12-01: Given that a frame ID does
6047 (or should) carry around the function and does (or
6048 should) use that when doing a frame comparison. */
6049 if (tp
->control
.stop_step
6050 && frame_id_eq (tp
->control
.step_frame_id
,
6051 get_frame_id (get_current_frame ()))
6052 && step_start_function
== find_pc_function (stop_pc
))
6053 source_flag
= SRC_LINE
; /* Finished step, just
6054 print source line. */
6056 source_flag
= SRC_AND_LOC
; /* Print location and
6059 case PRINT_SRC_AND_LOC
:
6060 source_flag
= SRC_AND_LOC
; /* Print location and
6063 case PRINT_SRC_ONLY
:
6064 source_flag
= SRC_LINE
;
6067 source_flag
= SRC_LINE
; /* something bogus */
6068 do_frame_printing
= 0;
6071 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6074 /* The behavior of this routine with respect to the source
6076 SRC_LINE: Print only source line
6077 LOCATION: Print only location
6078 SRC_AND_LOC: Print location and source line. */
6079 if (do_frame_printing
)
6080 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
6082 /* Display the auto-display expressions. */
6087 /* Save the function value return registers, if we care.
6088 We might be about to restore their previous contents. */
6089 if (inferior_thread ()->control
.proceed_to_finish
6090 && execution_direction
!= EXEC_REVERSE
)
6092 /* This should not be necessary. */
6094 regcache_xfree (stop_registers
);
6096 /* NB: The copy goes through to the target picking up the value of
6097 all the registers. */
6098 stop_registers
= regcache_dup (get_current_regcache ());
6101 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6103 /* Pop the empty frame that contains the stack dummy.
6104 This also restores inferior state prior to the call
6105 (struct infcall_suspend_state). */
6106 struct frame_info
*frame
= get_current_frame ();
6108 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6110 /* frame_pop() calls reinit_frame_cache as the last thing it
6111 does which means there's currently no selected frame. We
6112 don't need to re-establish a selected frame if the dummy call
6113 returns normally, that will be done by
6114 restore_infcall_control_state. However, we do have to handle
6115 the case where the dummy call is returning after being
6116 stopped (e.g. the dummy call previously hit a breakpoint).
6117 We can't know which case we have so just always re-establish
6118 a selected frame here. */
6119 select_frame (get_current_frame ());
6123 annotate_stopped ();
6125 /* Suppress the stop observer if we're in the middle of:
6127 - a step n (n > 1), as there still more steps to be done.
6129 - a "finish" command, as the observer will be called in
6130 finish_command_continuation, so it can include the inferior
6131 function's return value.
6133 - calling an inferior function, as we pretend we inferior didn't
6134 run at all. The return value of the call is handled by the
6135 expression evaluator, through call_function_by_hand. */
6137 if (!target_has_execution
6138 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6139 || last
.kind
== TARGET_WAITKIND_EXITED
6140 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6141 || (!(inferior_thread ()->step_multi
6142 && inferior_thread ()->control
.stop_step
)
6143 && !(inferior_thread ()->control
.stop_bpstat
6144 && inferior_thread ()->control
.proceed_to_finish
)
6145 && !inferior_thread ()->control
.in_infcall
))
6147 if (!ptid_equal (inferior_ptid
, null_ptid
))
6148 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6151 observer_notify_normal_stop (NULL
, stop_print_frame
);
6154 if (target_has_execution
)
6156 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6157 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6158 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6159 Delete any breakpoint that is to be deleted at the next stop. */
6160 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6163 /* Try to get rid of automatically added inferiors that are no
6164 longer needed. Keeping those around slows down things linearly.
6165 Note that this never removes the current inferior. */
6170 hook_stop_stub (void *cmd
)
6172 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6177 signal_stop_state (int signo
)
6179 return signal_stop
[signo
];
6183 signal_print_state (int signo
)
6185 return signal_print
[signo
];
6189 signal_pass_state (int signo
)
6191 return signal_program
[signo
];
6195 signal_cache_update (int signo
)
6199 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6200 signal_cache_update (signo
);
6205 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6206 && signal_print
[signo
] == 0
6207 && signal_program
[signo
] == 1);
6211 signal_stop_update (int signo
, int state
)
6213 int ret
= signal_stop
[signo
];
6215 signal_stop
[signo
] = state
;
6216 signal_cache_update (signo
);
6221 signal_print_update (int signo
, int state
)
6223 int ret
= signal_print
[signo
];
6225 signal_print
[signo
] = state
;
6226 signal_cache_update (signo
);
6231 signal_pass_update (int signo
, int state
)
6233 int ret
= signal_program
[signo
];
6235 signal_program
[signo
] = state
;
6236 signal_cache_update (signo
);
6241 sig_print_header (void)
6243 printf_filtered (_("Signal Stop\tPrint\tPass "
6244 "to program\tDescription\n"));
6248 sig_print_info (enum gdb_signal oursig
)
6250 const char *name
= gdb_signal_to_name (oursig
);
6251 int name_padding
= 13 - strlen (name
);
6253 if (name_padding
<= 0)
6256 printf_filtered ("%s", name
);
6257 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6258 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6259 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6260 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6261 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6264 /* Specify how various signals in the inferior should be handled. */
6267 handle_command (char *args
, int from_tty
)
6270 int digits
, wordlen
;
6271 int sigfirst
, signum
, siglast
;
6272 enum gdb_signal oursig
;
6275 unsigned char *sigs
;
6276 struct cleanup
*old_chain
;
6280 error_no_arg (_("signal to handle"));
6283 /* Allocate and zero an array of flags for which signals to handle. */
6285 nsigs
= (int) GDB_SIGNAL_LAST
;
6286 sigs
= (unsigned char *) alloca (nsigs
);
6287 memset (sigs
, 0, nsigs
);
6289 /* Break the command line up into args. */
6291 argv
= gdb_buildargv (args
);
6292 old_chain
= make_cleanup_freeargv (argv
);
6294 /* Walk through the args, looking for signal oursigs, signal names, and
6295 actions. Signal numbers and signal names may be interspersed with
6296 actions, with the actions being performed for all signals cumulatively
6297 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6299 while (*argv
!= NULL
)
6301 wordlen
= strlen (*argv
);
6302 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6306 sigfirst
= siglast
= -1;
6308 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6310 /* Apply action to all signals except those used by the
6311 debugger. Silently skip those. */
6314 siglast
= nsigs
- 1;
6316 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6318 SET_SIGS (nsigs
, sigs
, signal_stop
);
6319 SET_SIGS (nsigs
, sigs
, signal_print
);
6321 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6323 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6325 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6327 SET_SIGS (nsigs
, sigs
, signal_print
);
6329 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6331 SET_SIGS (nsigs
, sigs
, signal_program
);
6333 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6335 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6337 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6339 SET_SIGS (nsigs
, sigs
, signal_program
);
6341 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6343 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6344 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6346 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6348 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6350 else if (digits
> 0)
6352 /* It is numeric. The numeric signal refers to our own
6353 internal signal numbering from target.h, not to host/target
6354 signal number. This is a feature; users really should be
6355 using symbolic names anyway, and the common ones like
6356 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6358 sigfirst
= siglast
= (int)
6359 gdb_signal_from_command (atoi (*argv
));
6360 if ((*argv
)[digits
] == '-')
6363 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6365 if (sigfirst
> siglast
)
6367 /* Bet he didn't figure we'd think of this case... */
6375 oursig
= gdb_signal_from_name (*argv
);
6376 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
6378 sigfirst
= siglast
= (int) oursig
;
6382 /* Not a number and not a recognized flag word => complain. */
6383 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6387 /* If any signal numbers or symbol names were found, set flags for
6388 which signals to apply actions to. */
6390 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6392 switch ((enum gdb_signal
) signum
)
6394 case GDB_SIGNAL_TRAP
:
6395 case GDB_SIGNAL_INT
:
6396 if (!allsigs
&& !sigs
[signum
])
6398 if (query (_("%s is used by the debugger.\n\
6399 Are you sure you want to change it? "),
6400 gdb_signal_to_name ((enum gdb_signal
) signum
)))
6406 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6407 gdb_flush (gdb_stdout
);
6412 case GDB_SIGNAL_DEFAULT
:
6413 case GDB_SIGNAL_UNKNOWN
:
6414 /* Make sure that "all" doesn't print these. */
6425 for (signum
= 0; signum
< nsigs
; signum
++)
6428 signal_cache_update (-1);
6429 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6430 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
6434 /* Show the results. */
6435 sig_print_header ();
6436 for (; signum
< nsigs
; signum
++)
6438 sig_print_info (signum
);
6444 do_cleanups (old_chain
);
6447 /* Complete the "handle" command. */
6449 static VEC (char_ptr
) *
6450 handle_completer (struct cmd_list_element
*ignore
,
6451 char *text
, char *word
)
6453 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
6454 static const char * const keywords
[] =
6468 vec_signals
= signal_completer (ignore
, text
, word
);
6469 vec_keywords
= complete_on_enum (keywords
, word
, word
);
6471 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
6472 VEC_free (char_ptr
, vec_signals
);
6473 VEC_free (char_ptr
, vec_keywords
);
6478 xdb_handle_command (char *args
, int from_tty
)
6481 struct cleanup
*old_chain
;
6484 error_no_arg (_("xdb command"));
6486 /* Break the command line up into args. */
6488 argv
= gdb_buildargv (args
);
6489 old_chain
= make_cleanup_freeargv (argv
);
6490 if (argv
[1] != (char *) NULL
)
6495 bufLen
= strlen (argv
[0]) + 20;
6496 argBuf
= (char *) xmalloc (bufLen
);
6500 enum gdb_signal oursig
;
6502 oursig
= gdb_signal_from_name (argv
[0]);
6503 memset (argBuf
, 0, bufLen
);
6504 if (strcmp (argv
[1], "Q") == 0)
6505 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6508 if (strcmp (argv
[1], "s") == 0)
6510 if (!signal_stop
[oursig
])
6511 sprintf (argBuf
, "%s %s", argv
[0], "stop");
6513 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
6515 else if (strcmp (argv
[1], "i") == 0)
6517 if (!signal_program
[oursig
])
6518 sprintf (argBuf
, "%s %s", argv
[0], "pass");
6520 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
6522 else if (strcmp (argv
[1], "r") == 0)
6524 if (!signal_print
[oursig
])
6525 sprintf (argBuf
, "%s %s", argv
[0], "print");
6527 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6533 handle_command (argBuf
, from_tty
);
6535 printf_filtered (_("Invalid signal handling flag.\n"));
6540 do_cleanups (old_chain
);
6544 gdb_signal_from_command (int num
)
6546 if (num
>= 1 && num
<= 15)
6547 return (enum gdb_signal
) num
;
6548 error (_("Only signals 1-15 are valid as numeric signals.\n\
6549 Use \"info signals\" for a list of symbolic signals."));
6552 /* Print current contents of the tables set by the handle command.
6553 It is possible we should just be printing signals actually used
6554 by the current target (but for things to work right when switching
6555 targets, all signals should be in the signal tables). */
6558 signals_info (char *signum_exp
, int from_tty
)
6560 enum gdb_signal oursig
;
6562 sig_print_header ();
6566 /* First see if this is a symbol name. */
6567 oursig
= gdb_signal_from_name (signum_exp
);
6568 if (oursig
== GDB_SIGNAL_UNKNOWN
)
6570 /* No, try numeric. */
6572 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
6574 sig_print_info (oursig
);
6578 printf_filtered ("\n");
6579 /* These ugly casts brought to you by the native VAX compiler. */
6580 for (oursig
= GDB_SIGNAL_FIRST
;
6581 (int) oursig
< (int) GDB_SIGNAL_LAST
;
6582 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
6586 if (oursig
!= GDB_SIGNAL_UNKNOWN
6587 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
6588 sig_print_info (oursig
);
6591 printf_filtered (_("\nUse the \"handle\" command "
6592 "to change these tables.\n"));
6595 /* Check if it makes sense to read $_siginfo from the current thread
6596 at this point. If not, throw an error. */
6599 validate_siginfo_access (void)
6601 /* No current inferior, no siginfo. */
6602 if (ptid_equal (inferior_ptid
, null_ptid
))
6603 error (_("No thread selected."));
6605 /* Don't try to read from a dead thread. */
6606 if (is_exited (inferior_ptid
))
6607 error (_("The current thread has terminated"));
6609 /* ... or from a spinning thread. */
6610 if (is_running (inferior_ptid
))
6611 error (_("Selected thread is running."));
6614 /* The $_siginfo convenience variable is a bit special. We don't know
6615 for sure the type of the value until we actually have a chance to
6616 fetch the data. The type can change depending on gdbarch, so it is
6617 also dependent on which thread you have selected.
6619 1. making $_siginfo be an internalvar that creates a new value on
6622 2. making the value of $_siginfo be an lval_computed value. */
6624 /* This function implements the lval_computed support for reading a
6628 siginfo_value_read (struct value
*v
)
6630 LONGEST transferred
;
6632 validate_siginfo_access ();
6635 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
6637 value_contents_all_raw (v
),
6639 TYPE_LENGTH (value_type (v
)));
6641 if (transferred
!= TYPE_LENGTH (value_type (v
)))
6642 error (_("Unable to read siginfo"));
6645 /* This function implements the lval_computed support for writing a
6649 siginfo_value_write (struct value
*v
, struct value
*fromval
)
6651 LONGEST transferred
;
6653 validate_siginfo_access ();
6655 transferred
= target_write (¤t_target
,
6656 TARGET_OBJECT_SIGNAL_INFO
,
6658 value_contents_all_raw (fromval
),
6660 TYPE_LENGTH (value_type (fromval
)));
6662 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
6663 error (_("Unable to write siginfo"));
6666 static const struct lval_funcs siginfo_value_funcs
=
6672 /* Return a new value with the correct type for the siginfo object of
6673 the current thread using architecture GDBARCH. Return a void value
6674 if there's no object available. */
6676 static struct value
*
6677 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
6680 if (target_has_stack
6681 && !ptid_equal (inferior_ptid
, null_ptid
)
6682 && gdbarch_get_siginfo_type_p (gdbarch
))
6684 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6686 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
6689 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
6693 /* infcall_suspend_state contains state about the program itself like its
6694 registers and any signal it received when it last stopped.
6695 This state must be restored regardless of how the inferior function call
6696 ends (either successfully, or after it hits a breakpoint or signal)
6697 if the program is to properly continue where it left off. */
6699 struct infcall_suspend_state
6701 struct thread_suspend_state thread_suspend
;
6702 #if 0 /* Currently unused and empty structures are not valid C. */
6703 struct inferior_suspend_state inferior_suspend
;
6708 struct regcache
*registers
;
6710 /* Format of SIGINFO_DATA or NULL if it is not present. */
6711 struct gdbarch
*siginfo_gdbarch
;
6713 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
6714 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
6715 content would be invalid. */
6716 gdb_byte
*siginfo_data
;
6719 struct infcall_suspend_state
*
6720 save_infcall_suspend_state (void)
6722 struct infcall_suspend_state
*inf_state
;
6723 struct thread_info
*tp
= inferior_thread ();
6724 struct inferior
*inf
= current_inferior ();
6725 struct regcache
*regcache
= get_current_regcache ();
6726 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6727 gdb_byte
*siginfo_data
= NULL
;
6729 if (gdbarch_get_siginfo_type_p (gdbarch
))
6731 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6732 size_t len
= TYPE_LENGTH (type
);
6733 struct cleanup
*back_to
;
6735 siginfo_data
= xmalloc (len
);
6736 back_to
= make_cleanup (xfree
, siginfo_data
);
6738 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6739 siginfo_data
, 0, len
) == len
)
6740 discard_cleanups (back_to
);
6743 /* Errors ignored. */
6744 do_cleanups (back_to
);
6745 siginfo_data
= NULL
;
6749 inf_state
= XZALLOC (struct infcall_suspend_state
);
6753 inf_state
->siginfo_gdbarch
= gdbarch
;
6754 inf_state
->siginfo_data
= siginfo_data
;
6757 inf_state
->thread_suspend
= tp
->suspend
;
6758 #if 0 /* Currently unused and empty structures are not valid C. */
6759 inf_state
->inferior_suspend
= inf
->suspend
;
6762 /* run_inferior_call will not use the signal due to its `proceed' call with
6763 GDB_SIGNAL_0 anyway. */
6764 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6766 inf_state
->stop_pc
= stop_pc
;
6768 inf_state
->registers
= regcache_dup (regcache
);
6773 /* Restore inferior session state to INF_STATE. */
6776 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6778 struct thread_info
*tp
= inferior_thread ();
6779 struct inferior
*inf
= current_inferior ();
6780 struct regcache
*regcache
= get_current_regcache ();
6781 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6783 tp
->suspend
= inf_state
->thread_suspend
;
6784 #if 0 /* Currently unused and empty structures are not valid C. */
6785 inf
->suspend
= inf_state
->inferior_suspend
;
6788 stop_pc
= inf_state
->stop_pc
;
6790 if (inf_state
->siginfo_gdbarch
== gdbarch
)
6792 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6794 /* Errors ignored. */
6795 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6796 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
6799 /* The inferior can be gone if the user types "print exit(0)"
6800 (and perhaps other times). */
6801 if (target_has_execution
)
6802 /* NB: The register write goes through to the target. */
6803 regcache_cpy (regcache
, inf_state
->registers
);
6805 discard_infcall_suspend_state (inf_state
);
6809 do_restore_infcall_suspend_state_cleanup (void *state
)
6811 restore_infcall_suspend_state (state
);
6815 make_cleanup_restore_infcall_suspend_state
6816 (struct infcall_suspend_state
*inf_state
)
6818 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
6822 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6824 regcache_xfree (inf_state
->registers
);
6825 xfree (inf_state
->siginfo_data
);
6830 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
6832 return inf_state
->registers
;
6835 /* infcall_control_state contains state regarding gdb's control of the
6836 inferior itself like stepping control. It also contains session state like
6837 the user's currently selected frame. */
6839 struct infcall_control_state
6841 struct thread_control_state thread_control
;
6842 struct inferior_control_state inferior_control
;
6845 enum stop_stack_kind stop_stack_dummy
;
6846 int stopped_by_random_signal
;
6847 int stop_after_trap
;
6849 /* ID if the selected frame when the inferior function call was made. */
6850 struct frame_id selected_frame_id
;
6853 /* Save all of the information associated with the inferior<==>gdb
6856 struct infcall_control_state
*
6857 save_infcall_control_state (void)
6859 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
6860 struct thread_info
*tp
= inferior_thread ();
6861 struct inferior
*inf
= current_inferior ();
6863 inf_status
->thread_control
= tp
->control
;
6864 inf_status
->inferior_control
= inf
->control
;
6866 tp
->control
.step_resume_breakpoint
= NULL
;
6867 tp
->control
.exception_resume_breakpoint
= NULL
;
6869 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
6870 chain. If caller's caller is walking the chain, they'll be happier if we
6871 hand them back the original chain when restore_infcall_control_state is
6873 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
6876 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
6877 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
6878 inf_status
->stop_after_trap
= stop_after_trap
;
6880 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
6886 restore_selected_frame (void *args
)
6888 struct frame_id
*fid
= (struct frame_id
*) args
;
6889 struct frame_info
*frame
;
6891 frame
= frame_find_by_id (*fid
);
6893 /* If inf_status->selected_frame_id is NULL, there was no previously
6897 warning (_("Unable to restore previously selected frame."));
6901 select_frame (frame
);
6906 /* Restore inferior session state to INF_STATUS. */
6909 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
6911 struct thread_info
*tp
= inferior_thread ();
6912 struct inferior
*inf
= current_inferior ();
6914 if (tp
->control
.step_resume_breakpoint
)
6915 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
6917 if (tp
->control
.exception_resume_breakpoint
)
6918 tp
->control
.exception_resume_breakpoint
->disposition
6919 = disp_del_at_next_stop
;
6921 /* Handle the bpstat_copy of the chain. */
6922 bpstat_clear (&tp
->control
.stop_bpstat
);
6924 tp
->control
= inf_status
->thread_control
;
6925 inf
->control
= inf_status
->inferior_control
;
6928 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
6929 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
6930 stop_after_trap
= inf_status
->stop_after_trap
;
6932 if (target_has_stack
)
6934 /* The point of catch_errors is that if the stack is clobbered,
6935 walking the stack might encounter a garbage pointer and
6936 error() trying to dereference it. */
6938 (restore_selected_frame
, &inf_status
->selected_frame_id
,
6939 "Unable to restore previously selected frame:\n",
6940 RETURN_MASK_ERROR
) == 0)
6941 /* Error in restoring the selected frame. Select the innermost
6943 select_frame (get_current_frame ());
6950 do_restore_infcall_control_state_cleanup (void *sts
)
6952 restore_infcall_control_state (sts
);
6956 make_cleanup_restore_infcall_control_state
6957 (struct infcall_control_state
*inf_status
)
6959 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
6963 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
6965 if (inf_status
->thread_control
.step_resume_breakpoint
)
6966 inf_status
->thread_control
.step_resume_breakpoint
->disposition
6967 = disp_del_at_next_stop
;
6969 if (inf_status
->thread_control
.exception_resume_breakpoint
)
6970 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
6971 = disp_del_at_next_stop
;
6973 /* See save_infcall_control_state for info on stop_bpstat. */
6974 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
6980 ptid_match (ptid_t ptid
, ptid_t filter
)
6982 if (ptid_equal (filter
, minus_one_ptid
))
6984 if (ptid_is_pid (filter
)
6985 && ptid_get_pid (ptid
) == ptid_get_pid (filter
))
6987 else if (ptid_equal (ptid
, filter
))
6993 /* restore_inferior_ptid() will be used by the cleanup machinery
6994 to restore the inferior_ptid value saved in a call to
6995 save_inferior_ptid(). */
6998 restore_inferior_ptid (void *arg
)
7000 ptid_t
*saved_ptid_ptr
= arg
;
7002 inferior_ptid
= *saved_ptid_ptr
;
7006 /* Save the value of inferior_ptid so that it may be restored by a
7007 later call to do_cleanups(). Returns the struct cleanup pointer
7008 needed for later doing the cleanup. */
7011 save_inferior_ptid (void)
7013 ptid_t
*saved_ptid_ptr
;
7015 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
7016 *saved_ptid_ptr
= inferior_ptid
;
7017 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
7021 /* User interface for reverse debugging:
7022 Set exec-direction / show exec-direction commands
7023 (returns error unless target implements to_set_exec_direction method). */
7025 int execution_direction
= EXEC_FORWARD
;
7026 static const char exec_forward
[] = "forward";
7027 static const char exec_reverse
[] = "reverse";
7028 static const char *exec_direction
= exec_forward
;
7029 static const char *const exec_direction_names
[] = {
7036 set_exec_direction_func (char *args
, int from_tty
,
7037 struct cmd_list_element
*cmd
)
7039 if (target_can_execute_reverse
)
7041 if (!strcmp (exec_direction
, exec_forward
))
7042 execution_direction
= EXEC_FORWARD
;
7043 else if (!strcmp (exec_direction
, exec_reverse
))
7044 execution_direction
= EXEC_REVERSE
;
7048 exec_direction
= exec_forward
;
7049 error (_("Target does not support this operation."));
7054 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7055 struct cmd_list_element
*cmd
, const char *value
)
7057 switch (execution_direction
) {
7059 fprintf_filtered (out
, _("Forward.\n"));
7062 fprintf_filtered (out
, _("Reverse.\n"));
7065 internal_error (__FILE__
, __LINE__
,
7066 _("bogus execution_direction value: %d"),
7067 (int) execution_direction
);
7071 /* User interface for non-stop mode. */
7076 set_non_stop (char *args
, int from_tty
,
7077 struct cmd_list_element
*c
)
7079 if (target_has_execution
)
7081 non_stop_1
= non_stop
;
7082 error (_("Cannot change this setting while the inferior is running."));
7085 non_stop
= non_stop_1
;
7089 show_non_stop (struct ui_file
*file
, int from_tty
,
7090 struct cmd_list_element
*c
, const char *value
)
7092 fprintf_filtered (file
,
7093 _("Controlling the inferior in non-stop mode is %s.\n"),
7098 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7099 struct cmd_list_element
*c
, const char *value
)
7101 fprintf_filtered (file
, _("Resuming the execution of threads "
7102 "of all processes is %s.\n"), value
);
7105 /* Implementation of `siginfo' variable. */
7107 static const struct internalvar_funcs siginfo_funcs
=
7115 _initialize_infrun (void)
7119 struct cmd_list_element
*c
;
7121 add_info ("signals", signals_info
, _("\
7122 What debugger does when program gets various signals.\n\
7123 Specify a signal as argument to print info on that signal only."));
7124 add_info_alias ("handle", "signals", 0);
7126 c
= add_com ("handle", class_run
, handle_command
, _("\
7127 Specify how to handle signals.\n\
7128 Usage: handle SIGNAL [ACTIONS]\n\
7129 Args are signals and actions to apply to those signals.\n\
7130 If no actions are specified, the current settings for the specified signals\n\
7131 will be displayed instead.\n\
7133 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7134 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7135 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7136 The special arg \"all\" is recognized to mean all signals except those\n\
7137 used by the debugger, typically SIGTRAP and SIGINT.\n\
7139 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7140 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7141 Stop means reenter debugger if this signal happens (implies print).\n\
7142 Print means print a message if this signal happens.\n\
7143 Pass means let program see this signal; otherwise program doesn't know.\n\
7144 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7145 Pass and Stop may be combined.\n\
7147 Multiple signals may be specified. Signal numbers and signal names\n\
7148 may be interspersed with actions, with the actions being performed for\n\
7149 all signals cumulatively specified."));
7150 set_cmd_completer (c
, handle_completer
);
7154 add_com ("lz", class_info
, signals_info
, _("\
7155 What debugger does when program gets various signals.\n\
7156 Specify a signal as argument to print info on that signal only."));
7157 add_com ("z", class_run
, xdb_handle_command
, _("\
7158 Specify how to handle a signal.\n\
7159 Args are signals and actions to apply to those signals.\n\
7160 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7161 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7162 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7163 The special arg \"all\" is recognized to mean all signals except those\n\
7164 used by the debugger, typically SIGTRAP and SIGINT.\n\
7165 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7166 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7167 nopass), \"Q\" (noprint)\n\
7168 Stop means reenter debugger if this signal happens (implies print).\n\
7169 Print means print a message if this signal happens.\n\
7170 Pass means let program see this signal; otherwise program doesn't know.\n\
7171 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7172 Pass and Stop may be combined."));
7176 stop_command
= add_cmd ("stop", class_obscure
,
7177 not_just_help_class_command
, _("\
7178 There is no `stop' command, but you can set a hook on `stop'.\n\
7179 This allows you to set a list of commands to be run each time execution\n\
7180 of the program stops."), &cmdlist
);
7182 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7183 Set inferior debugging."), _("\
7184 Show inferior debugging."), _("\
7185 When non-zero, inferior specific debugging is enabled."),
7188 &setdebuglist
, &showdebuglist
);
7190 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7191 &debug_displaced
, _("\
7192 Set displaced stepping debugging."), _("\
7193 Show displaced stepping debugging."), _("\
7194 When non-zero, displaced stepping specific debugging is enabled."),
7196 show_debug_displaced
,
7197 &setdebuglist
, &showdebuglist
);
7199 add_setshow_boolean_cmd ("non-stop", no_class
,
7201 Set whether gdb controls the inferior in non-stop mode."), _("\
7202 Show whether gdb controls the inferior in non-stop mode."), _("\
7203 When debugging a multi-threaded program and this setting is\n\
7204 off (the default, also called all-stop mode), when one thread stops\n\
7205 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7206 all other threads in the program while you interact with the thread of\n\
7207 interest. When you continue or step a thread, you can allow the other\n\
7208 threads to run, or have them remain stopped, but while you inspect any\n\
7209 thread's state, all threads stop.\n\
7211 In non-stop mode, when one thread stops, other threads can continue\n\
7212 to run freely. You'll be able to step each thread independently,\n\
7213 leave it stopped or free to run as needed."),
7219 numsigs
= (int) GDB_SIGNAL_LAST
;
7220 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7221 signal_print
= (unsigned char *)
7222 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7223 signal_program
= (unsigned char *)
7224 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7225 signal_pass
= (unsigned char *)
7226 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7227 for (i
= 0; i
< numsigs
; i
++)
7230 signal_print
[i
] = 1;
7231 signal_program
[i
] = 1;
7234 /* Signals caused by debugger's own actions
7235 should not be given to the program afterwards. */
7236 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7237 signal_program
[GDB_SIGNAL_INT
] = 0;
7239 /* Signals that are not errors should not normally enter the debugger. */
7240 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7241 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7242 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7243 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7244 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7245 signal_print
[GDB_SIGNAL_PROF
] = 0;
7246 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7247 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7248 signal_stop
[GDB_SIGNAL_IO
] = 0;
7249 signal_print
[GDB_SIGNAL_IO
] = 0;
7250 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7251 signal_print
[GDB_SIGNAL_POLL
] = 0;
7252 signal_stop
[GDB_SIGNAL_URG
] = 0;
7253 signal_print
[GDB_SIGNAL_URG
] = 0;
7254 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7255 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7256 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7257 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7259 /* These signals are used internally by user-level thread
7260 implementations. (See signal(5) on Solaris.) Like the above
7261 signals, a healthy program receives and handles them as part of
7262 its normal operation. */
7263 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7264 signal_print
[GDB_SIGNAL_LWP
] = 0;
7265 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7266 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7267 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7268 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7270 /* Update cached state. */
7271 signal_cache_update (-1);
7273 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7274 &stop_on_solib_events
, _("\
7275 Set stopping for shared library events."), _("\
7276 Show stopping for shared library events."), _("\
7277 If nonzero, gdb will give control to the user when the dynamic linker\n\
7278 notifies gdb of shared library events. The most common event of interest\n\
7279 to the user would be loading/unloading of a new library."),
7281 show_stop_on_solib_events
,
7282 &setlist
, &showlist
);
7284 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7285 follow_fork_mode_kind_names
,
7286 &follow_fork_mode_string
, _("\
7287 Set debugger response to a program call of fork or vfork."), _("\
7288 Show debugger response to a program call of fork or vfork."), _("\
7289 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7290 parent - the original process is debugged after a fork\n\
7291 child - the new process is debugged after a fork\n\
7292 The unfollowed process will continue to run.\n\
7293 By default, the debugger will follow the parent process."),
7295 show_follow_fork_mode_string
,
7296 &setlist
, &showlist
);
7298 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7299 follow_exec_mode_names
,
7300 &follow_exec_mode_string
, _("\
7301 Set debugger response to a program call of exec."), _("\
7302 Show debugger response to a program call of exec."), _("\
7303 An exec call replaces the program image of a process.\n\
7305 follow-exec-mode can be:\n\
7307 new - the debugger creates a new inferior and rebinds the process\n\
7308 to this new inferior. The program the process was running before\n\
7309 the exec call can be restarted afterwards by restarting the original\n\
7312 same - the debugger keeps the process bound to the same inferior.\n\
7313 The new executable image replaces the previous executable loaded in\n\
7314 the inferior. Restarting the inferior after the exec call restarts\n\
7315 the executable the process was running after the exec call.\n\
7317 By default, the debugger will use the same inferior."),
7319 show_follow_exec_mode_string
,
7320 &setlist
, &showlist
);
7322 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7323 scheduler_enums
, &scheduler_mode
, _("\
7324 Set mode for locking scheduler during execution."), _("\
7325 Show mode for locking scheduler during execution."), _("\
7326 off == no locking (threads may preempt at any time)\n\
7327 on == full locking (no thread except the current thread may run)\n\
7328 step == scheduler locked during every single-step operation.\n\
7329 In this mode, no other thread may run during a step command.\n\
7330 Other threads may run while stepping over a function call ('next')."),
7331 set_schedlock_func
, /* traps on target vector */
7332 show_scheduler_mode
,
7333 &setlist
, &showlist
);
7335 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7336 Set mode for resuming threads of all processes."), _("\
7337 Show mode for resuming threads of all processes."), _("\
7338 When on, execution commands (such as 'continue' or 'next') resume all\n\
7339 threads of all processes. When off (which is the default), execution\n\
7340 commands only resume the threads of the current process. The set of\n\
7341 threads that are resumed is further refined by the scheduler-locking\n\
7342 mode (see help set scheduler-locking)."),
7344 show_schedule_multiple
,
7345 &setlist
, &showlist
);
7347 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7348 Set mode of the step operation."), _("\
7349 Show mode of the step operation."), _("\
7350 When set, doing a step over a function without debug line information\n\
7351 will stop at the first instruction of that function. Otherwise, the\n\
7352 function is skipped and the step command stops at a different source line."),
7354 show_step_stop_if_no_debug
,
7355 &setlist
, &showlist
);
7357 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
7358 &can_use_displaced_stepping
, _("\
7359 Set debugger's willingness to use displaced stepping."), _("\
7360 Show debugger's willingness to use displaced stepping."), _("\
7361 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7362 supported by the target architecture. If off, gdb will not use displaced\n\
7363 stepping to step over breakpoints, even if such is supported by the target\n\
7364 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7365 if the target architecture supports it and non-stop mode is active, but will not\n\
7366 use it in all-stop mode (see help set non-stop)."),
7368 show_can_use_displaced_stepping
,
7369 &setlist
, &showlist
);
7371 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7372 &exec_direction
, _("Set direction of execution.\n\
7373 Options are 'forward' or 'reverse'."),
7374 _("Show direction of execution (forward/reverse)."),
7375 _("Tells gdb whether to execute forward or backward."),
7376 set_exec_direction_func
, show_exec_direction_func
,
7377 &setlist
, &showlist
);
7379 /* Set/show detach-on-fork: user-settable mode. */
7381 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7382 Set whether gdb will detach the child of a fork."), _("\
7383 Show whether gdb will detach the child of a fork."), _("\
7384 Tells gdb whether to detach the child of a fork."),
7385 NULL
, NULL
, &setlist
, &showlist
);
7387 /* Set/show disable address space randomization mode. */
7389 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7390 &disable_randomization
, _("\
7391 Set disabling of debuggee's virtual address space randomization."), _("\
7392 Show disabling of debuggee's virtual address space randomization."), _("\
7393 When this mode is on (which is the default), randomization of the virtual\n\
7394 address space is disabled. Standalone programs run with the randomization\n\
7395 enabled by default on some platforms."),
7396 &set_disable_randomization
,
7397 &show_disable_randomization
,
7398 &setlist
, &showlist
);
7400 /* ptid initializations */
7401 inferior_ptid
= null_ptid
;
7402 target_last_wait_ptid
= minus_one_ptid
;
7404 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7405 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7406 observer_attach_thread_exit (infrun_thread_thread_exit
);
7407 observer_attach_inferior_exit (infrun_inferior_exit
);
7409 /* Explicitly create without lookup, since that tries to create a
7410 value with a void typed value, and when we get here, gdbarch
7411 isn't initialized yet. At this point, we're quite sure there
7412 isn't another convenience variable of the same name. */
7413 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7415 add_setshow_boolean_cmd ("observer", no_class
,
7416 &observer_mode_1
, _("\
7417 Set whether gdb controls the inferior in observer mode."), _("\
7418 Show whether gdb controls the inferior in observer mode."), _("\
7419 In observer mode, GDB can get data from the inferior, but not\n\
7420 affect its execution. Registers and memory may not be changed,\n\
7421 breakpoints may not be set, and the program cannot be interrupted\n\