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"
61 /* Prototypes for local functions */
63 static void signals_info (char *, int);
65 static void handle_command (char *, int);
67 static void sig_print_info (enum gdb_signal
);
69 static void sig_print_header (void);
71 static void resume_cleanups (void *);
73 static int hook_stop_stub (void *);
75 static int restore_selected_frame (void *);
77 static int follow_fork (void);
79 static void set_schedlock_func (char *args
, int from_tty
,
80 struct cmd_list_element
*c
);
82 static int currently_stepping (struct thread_info
*tp
);
84 static int currently_stepping_or_nexting_callback (struct thread_info
*tp
,
87 static void xdb_handle_command (char *args
, int from_tty
);
89 static int prepare_to_proceed (int);
91 static void print_exited_reason (int exitstatus
);
93 static void print_signal_exited_reason (enum gdb_signal siggnal
);
95 static void print_no_history_reason (void);
97 static void print_signal_received_reason (enum gdb_signal siggnal
);
99 static void print_end_stepping_range_reason (void);
101 void _initialize_infrun (void);
103 void nullify_last_target_wait_ptid (void);
105 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
107 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
109 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
111 /* When set, stop the 'step' command if we enter a function which has
112 no line number information. The normal behavior is that we step
113 over such function. */
114 int step_stop_if_no_debug
= 0;
116 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
117 struct cmd_list_element
*c
, const char *value
)
119 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
122 /* In asynchronous mode, but simulating synchronous execution. */
124 int sync_execution
= 0;
126 /* wait_for_inferior and normal_stop use this to notify the user
127 when the inferior stopped in a different thread than it had been
130 static ptid_t previous_inferior_ptid
;
132 /* Default behavior is to detach newly forked processes (legacy). */
135 int debug_displaced
= 0;
137 show_debug_displaced (struct ui_file
*file
, int from_tty
,
138 struct cmd_list_element
*c
, const char *value
)
140 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
143 int debug_infrun
= 0;
145 show_debug_infrun (struct ui_file
*file
, int from_tty
,
146 struct cmd_list_element
*c
, const char *value
)
148 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
152 /* Support for disabling address space randomization. */
154 int disable_randomization
= 1;
157 show_disable_randomization (struct ui_file
*file
, int from_tty
,
158 struct cmd_list_element
*c
, const char *value
)
160 if (target_supports_disable_randomization ())
161 fprintf_filtered (file
,
162 _("Disabling randomization of debuggee's "
163 "virtual address space is %s.\n"),
166 fputs_filtered (_("Disabling randomization of debuggee's "
167 "virtual address space is unsupported on\n"
168 "this platform.\n"), file
);
172 set_disable_randomization (char *args
, int from_tty
,
173 struct cmd_list_element
*c
)
175 if (!target_supports_disable_randomization ())
176 error (_("Disabling randomization of debuggee's "
177 "virtual address space is unsupported on\n"
182 /* If the program uses ELF-style shared libraries, then calls to
183 functions in shared libraries go through stubs, which live in a
184 table called the PLT (Procedure Linkage Table). The first time the
185 function is called, the stub sends control to the dynamic linker,
186 which looks up the function's real address, patches the stub so
187 that future calls will go directly to the function, and then passes
188 control to the function.
190 If we are stepping at the source level, we don't want to see any of
191 this --- we just want to skip over the stub and the dynamic linker.
192 The simple approach is to single-step until control leaves the
195 However, on some systems (e.g., Red Hat's 5.2 distribution) the
196 dynamic linker calls functions in the shared C library, so you
197 can't tell from the PC alone whether the dynamic linker is still
198 running. In this case, we use a step-resume breakpoint to get us
199 past the dynamic linker, as if we were using "next" to step over a
202 in_solib_dynsym_resolve_code() says whether we're in the dynamic
203 linker code or not. Normally, this means we single-step. However,
204 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
205 address where we can place a step-resume breakpoint to get past the
206 linker's symbol resolution function.
208 in_solib_dynsym_resolve_code() can generally be implemented in a
209 pretty portable way, by comparing the PC against the address ranges
210 of the dynamic linker's sections.
212 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
213 it depends on internal details of the dynamic linker. It's usually
214 not too hard to figure out where to put a breakpoint, but it
215 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
216 sanity checking. If it can't figure things out, returning zero and
217 getting the (possibly confusing) stepping behavior is better than
218 signalling an error, which will obscure the change in the
221 /* This function returns TRUE if pc is the address of an instruction
222 that lies within the dynamic linker (such as the event hook, or the
225 This function must be used only when a dynamic linker event has
226 been caught, and the inferior is being stepped out of the hook, or
227 undefined results are guaranteed. */
229 #ifndef SOLIB_IN_DYNAMIC_LINKER
230 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
233 /* "Observer mode" is somewhat like a more extreme version of
234 non-stop, in which all GDB operations that might affect the
235 target's execution have been disabled. */
237 static int non_stop_1
= 0;
239 int observer_mode
= 0;
240 static int observer_mode_1
= 0;
243 set_observer_mode (char *args
, int from_tty
,
244 struct cmd_list_element
*c
)
246 extern int pagination_enabled
;
248 if (target_has_execution
)
250 observer_mode_1
= observer_mode
;
251 error (_("Cannot change this setting while the inferior is running."));
254 observer_mode
= observer_mode_1
;
256 may_write_registers
= !observer_mode
;
257 may_write_memory
= !observer_mode
;
258 may_insert_breakpoints
= !observer_mode
;
259 may_insert_tracepoints
= !observer_mode
;
260 /* We can insert fast tracepoints in or out of observer mode,
261 but enable them if we're going into this mode. */
263 may_insert_fast_tracepoints
= 1;
264 may_stop
= !observer_mode
;
265 update_target_permissions ();
267 /* Going *into* observer mode we must force non-stop, then
268 going out we leave it that way. */
271 target_async_permitted
= 1;
272 pagination_enabled
= 0;
273 non_stop
= non_stop_1
= 1;
277 printf_filtered (_("Observer mode is now %s.\n"),
278 (observer_mode
? "on" : "off"));
282 show_observer_mode (struct ui_file
*file
, int from_tty
,
283 struct cmd_list_element
*c
, const char *value
)
285 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
288 /* This updates the value of observer mode based on changes in
289 permissions. Note that we are deliberately ignoring the values of
290 may-write-registers and may-write-memory, since the user may have
291 reason to enable these during a session, for instance to turn on a
292 debugging-related global. */
295 update_observer_mode (void)
299 newval
= (!may_insert_breakpoints
300 && !may_insert_tracepoints
301 && may_insert_fast_tracepoints
305 /* Let the user know if things change. */
306 if (newval
!= observer_mode
)
307 printf_filtered (_("Observer mode is now %s.\n"),
308 (newval
? "on" : "off"));
310 observer_mode
= observer_mode_1
= newval
;
313 /* Tables of how to react to signals; the user sets them. */
315 static unsigned char *signal_stop
;
316 static unsigned char *signal_print
;
317 static unsigned char *signal_program
;
319 /* Table of signals that the target may silently handle.
320 This is automatically determined from the flags above,
321 and simply cached here. */
322 static unsigned char *signal_pass
;
324 #define SET_SIGS(nsigs,sigs,flags) \
326 int signum = (nsigs); \
327 while (signum-- > 0) \
328 if ((sigs)[signum]) \
329 (flags)[signum] = 1; \
332 #define UNSET_SIGS(nsigs,sigs,flags) \
334 int signum = (nsigs); \
335 while (signum-- > 0) \
336 if ((sigs)[signum]) \
337 (flags)[signum] = 0; \
340 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
341 this function is to avoid exporting `signal_program'. */
344 update_signals_program_target (void)
346 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
349 /* Value to pass to target_resume() to cause all threads to resume. */
351 #define RESUME_ALL minus_one_ptid
353 /* Command list pointer for the "stop" placeholder. */
355 static struct cmd_list_element
*stop_command
;
357 /* Function inferior was in as of last step command. */
359 static struct symbol
*step_start_function
;
361 /* Nonzero if we want to give control to the user when we're notified
362 of shared library events by the dynamic linker. */
363 int stop_on_solib_events
;
365 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
366 struct cmd_list_element
*c
, const char *value
)
368 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
372 /* Nonzero means expecting a trace trap
373 and should stop the inferior and return silently when it happens. */
377 /* Save register contents here when executing a "finish" command or are
378 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
379 Thus this contains the return value from the called function (assuming
380 values are returned in a register). */
382 struct regcache
*stop_registers
;
384 /* Nonzero after stop if current stack frame should be printed. */
386 static int stop_print_frame
;
388 /* This is a cached copy of the pid/waitstatus of the last event
389 returned by target_wait()/deprecated_target_wait_hook(). This
390 information is returned by get_last_target_status(). */
391 static ptid_t target_last_wait_ptid
;
392 static struct target_waitstatus target_last_waitstatus
;
394 static void context_switch (ptid_t ptid
);
396 void init_thread_stepping_state (struct thread_info
*tss
);
398 void init_infwait_state (void);
400 static const char follow_fork_mode_child
[] = "child";
401 static const char follow_fork_mode_parent
[] = "parent";
403 static const char *const follow_fork_mode_kind_names
[] = {
404 follow_fork_mode_child
,
405 follow_fork_mode_parent
,
409 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
411 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
412 struct cmd_list_element
*c
, const char *value
)
414 fprintf_filtered (file
,
415 _("Debugger response to a program "
416 "call of fork or vfork is \"%s\".\n"),
421 /* Tell the target to follow the fork we're stopped at. Returns true
422 if the inferior should be resumed; false, if the target for some
423 reason decided it's best not to resume. */
428 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
429 int should_resume
= 1;
430 struct thread_info
*tp
;
432 /* Copy user stepping state to the new inferior thread. FIXME: the
433 followed fork child thread should have a copy of most of the
434 parent thread structure's run control related fields, not just these.
435 Initialized to avoid "may be used uninitialized" warnings from gcc. */
436 struct breakpoint
*step_resume_breakpoint
= NULL
;
437 struct breakpoint
*exception_resume_breakpoint
= NULL
;
438 CORE_ADDR step_range_start
= 0;
439 CORE_ADDR step_range_end
= 0;
440 struct frame_id step_frame_id
= { 0 };
445 struct target_waitstatus wait_status
;
447 /* Get the last target status returned by target_wait(). */
448 get_last_target_status (&wait_ptid
, &wait_status
);
450 /* If not stopped at a fork event, then there's nothing else to
452 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
453 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
456 /* Check if we switched over from WAIT_PTID, since the event was
458 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
459 && !ptid_equal (inferior_ptid
, wait_ptid
))
461 /* We did. Switch back to WAIT_PTID thread, to tell the
462 target to follow it (in either direction). We'll
463 afterwards refuse to resume, and inform the user what
465 switch_to_thread (wait_ptid
);
470 tp
= inferior_thread ();
472 /* If there were any forks/vforks that were caught and are now to be
473 followed, then do so now. */
474 switch (tp
->pending_follow
.kind
)
476 case TARGET_WAITKIND_FORKED
:
477 case TARGET_WAITKIND_VFORKED
:
479 ptid_t parent
, child
;
481 /* If the user did a next/step, etc, over a fork call,
482 preserve the stepping state in the fork child. */
483 if (follow_child
&& should_resume
)
485 step_resume_breakpoint
= clone_momentary_breakpoint
486 (tp
->control
.step_resume_breakpoint
);
487 step_range_start
= tp
->control
.step_range_start
;
488 step_range_end
= tp
->control
.step_range_end
;
489 step_frame_id
= tp
->control
.step_frame_id
;
490 exception_resume_breakpoint
491 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
493 /* For now, delete the parent's sr breakpoint, otherwise,
494 parent/child sr breakpoints are considered duplicates,
495 and the child version will not be installed. Remove
496 this when the breakpoints module becomes aware of
497 inferiors and address spaces. */
498 delete_step_resume_breakpoint (tp
);
499 tp
->control
.step_range_start
= 0;
500 tp
->control
.step_range_end
= 0;
501 tp
->control
.step_frame_id
= null_frame_id
;
502 delete_exception_resume_breakpoint (tp
);
505 parent
= inferior_ptid
;
506 child
= tp
->pending_follow
.value
.related_pid
;
508 /* Tell the target to do whatever is necessary to follow
509 either parent or child. */
510 if (target_follow_fork (follow_child
))
512 /* Target refused to follow, or there's some other reason
513 we shouldn't resume. */
518 /* This pending follow fork event is now handled, one way
519 or another. The previous selected thread may be gone
520 from the lists by now, but if it is still around, need
521 to clear the pending follow request. */
522 tp
= find_thread_ptid (parent
);
524 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
526 /* This makes sure we don't try to apply the "Switched
527 over from WAIT_PID" logic above. */
528 nullify_last_target_wait_ptid ();
530 /* If we followed the child, switch to it... */
533 switch_to_thread (child
);
535 /* ... and preserve the stepping state, in case the
536 user was stepping over the fork call. */
539 tp
= inferior_thread ();
540 tp
->control
.step_resume_breakpoint
541 = step_resume_breakpoint
;
542 tp
->control
.step_range_start
= step_range_start
;
543 tp
->control
.step_range_end
= step_range_end
;
544 tp
->control
.step_frame_id
= step_frame_id
;
545 tp
->control
.exception_resume_breakpoint
546 = exception_resume_breakpoint
;
550 /* If we get here, it was because we're trying to
551 resume from a fork catchpoint, but, the user
552 has switched threads away from the thread that
553 forked. In that case, the resume command
554 issued is most likely not applicable to the
555 child, so just warn, and refuse to resume. */
556 warning (_("Not resuming: switched threads "
557 "before following fork child.\n"));
560 /* Reset breakpoints in the child as appropriate. */
561 follow_inferior_reset_breakpoints ();
564 switch_to_thread (parent
);
568 case TARGET_WAITKIND_SPURIOUS
:
569 /* Nothing to follow. */
572 internal_error (__FILE__
, __LINE__
,
573 "Unexpected pending_follow.kind %d\n",
574 tp
->pending_follow
.kind
);
578 return should_resume
;
582 follow_inferior_reset_breakpoints (void)
584 struct thread_info
*tp
= inferior_thread ();
586 /* Was there a step_resume breakpoint? (There was if the user
587 did a "next" at the fork() call.) If so, explicitly reset its
590 step_resumes are a form of bp that are made to be per-thread.
591 Since we created the step_resume bp when the parent process
592 was being debugged, and now are switching to the child process,
593 from the breakpoint package's viewpoint, that's a switch of
594 "threads". We must update the bp's notion of which thread
595 it is for, or it'll be ignored when it triggers. */
597 if (tp
->control
.step_resume_breakpoint
)
598 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
600 if (tp
->control
.exception_resume_breakpoint
)
601 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
603 /* Reinsert all breakpoints in the child. The user may have set
604 breakpoints after catching the fork, in which case those
605 were never set in the child, but only in the parent. This makes
606 sure the inserted breakpoints match the breakpoint list. */
608 breakpoint_re_set ();
609 insert_breakpoints ();
612 /* The child has exited or execed: resume threads of the parent the
613 user wanted to be executing. */
616 proceed_after_vfork_done (struct thread_info
*thread
,
619 int pid
= * (int *) arg
;
621 if (ptid_get_pid (thread
->ptid
) == pid
622 && is_running (thread
->ptid
)
623 && !is_executing (thread
->ptid
)
624 && !thread
->stop_requested
625 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
628 fprintf_unfiltered (gdb_stdlog
,
629 "infrun: resuming vfork parent thread %s\n",
630 target_pid_to_str (thread
->ptid
));
632 switch_to_thread (thread
->ptid
);
633 clear_proceed_status ();
634 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
, 0);
640 /* Called whenever we notice an exec or exit event, to handle
641 detaching or resuming a vfork parent. */
644 handle_vfork_child_exec_or_exit (int exec
)
646 struct inferior
*inf
= current_inferior ();
648 if (inf
->vfork_parent
)
650 int resume_parent
= -1;
652 /* This exec or exit marks the end of the shared memory region
653 between the parent and the child. If the user wanted to
654 detach from the parent, now is the time. */
656 if (inf
->vfork_parent
->pending_detach
)
658 struct thread_info
*tp
;
659 struct cleanup
*old_chain
;
660 struct program_space
*pspace
;
661 struct address_space
*aspace
;
663 /* follow-fork child, detach-on-fork on. */
665 old_chain
= make_cleanup_restore_current_thread ();
667 /* We're letting loose of the parent. */
668 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
669 switch_to_thread (tp
->ptid
);
671 /* We're about to detach from the parent, which implicitly
672 removes breakpoints from its address space. There's a
673 catch here: we want to reuse the spaces for the child,
674 but, parent/child are still sharing the pspace at this
675 point, although the exec in reality makes the kernel give
676 the child a fresh set of new pages. The problem here is
677 that the breakpoints module being unaware of this, would
678 likely chose the child process to write to the parent
679 address space. Swapping the child temporarily away from
680 the spaces has the desired effect. Yes, this is "sort
683 pspace
= inf
->pspace
;
684 aspace
= inf
->aspace
;
688 if (debug_infrun
|| info_verbose
)
690 target_terminal_ours ();
693 fprintf_filtered (gdb_stdlog
,
694 "Detaching vfork parent process "
695 "%d after child exec.\n",
696 inf
->vfork_parent
->pid
);
698 fprintf_filtered (gdb_stdlog
,
699 "Detaching vfork parent process "
700 "%d after child exit.\n",
701 inf
->vfork_parent
->pid
);
704 target_detach (NULL
, 0);
707 inf
->pspace
= pspace
;
708 inf
->aspace
= aspace
;
710 do_cleanups (old_chain
);
714 /* We're staying attached to the parent, so, really give the
715 child a new address space. */
716 inf
->pspace
= add_program_space (maybe_new_address_space ());
717 inf
->aspace
= inf
->pspace
->aspace
;
719 set_current_program_space (inf
->pspace
);
721 resume_parent
= inf
->vfork_parent
->pid
;
723 /* Break the bonds. */
724 inf
->vfork_parent
->vfork_child
= NULL
;
728 struct cleanup
*old_chain
;
729 struct program_space
*pspace
;
731 /* If this is a vfork child exiting, then the pspace and
732 aspaces were shared with the parent. Since we're
733 reporting the process exit, we'll be mourning all that is
734 found in the address space, and switching to null_ptid,
735 preparing to start a new inferior. But, since we don't
736 want to clobber the parent's address/program spaces, we
737 go ahead and create a new one for this exiting
740 /* Switch to null_ptid, so that clone_program_space doesn't want
741 to read the selected frame of a dead process. */
742 old_chain
= save_inferior_ptid ();
743 inferior_ptid
= null_ptid
;
745 /* This inferior is dead, so avoid giving the breakpoints
746 module the option to write through to it (cloning a
747 program space resets breakpoints). */
750 pspace
= add_program_space (maybe_new_address_space ());
751 set_current_program_space (pspace
);
753 inf
->symfile_flags
= SYMFILE_NO_READ
;
754 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
755 inf
->pspace
= pspace
;
756 inf
->aspace
= pspace
->aspace
;
758 /* Put back inferior_ptid. We'll continue mourning this
760 do_cleanups (old_chain
);
762 resume_parent
= inf
->vfork_parent
->pid
;
763 /* Break the bonds. */
764 inf
->vfork_parent
->vfork_child
= NULL
;
767 inf
->vfork_parent
= NULL
;
769 gdb_assert (current_program_space
== inf
->pspace
);
771 if (non_stop
&& resume_parent
!= -1)
773 /* If the user wanted the parent to be running, let it go
775 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
778 fprintf_unfiltered (gdb_stdlog
,
779 "infrun: resuming vfork parent process %d\n",
782 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
784 do_cleanups (old_chain
);
789 /* Enum strings for "set|show displaced-stepping". */
791 static const char follow_exec_mode_new
[] = "new";
792 static const char follow_exec_mode_same
[] = "same";
793 static const char *const follow_exec_mode_names
[] =
795 follow_exec_mode_new
,
796 follow_exec_mode_same
,
800 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
802 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
803 struct cmd_list_element
*c
, const char *value
)
805 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
808 /* EXECD_PATHNAME is assumed to be non-NULL. */
811 follow_exec (ptid_t pid
, char *execd_pathname
)
813 struct thread_info
*th
= inferior_thread ();
814 struct inferior
*inf
= current_inferior ();
816 /* This is an exec event that we actually wish to pay attention to.
817 Refresh our symbol table to the newly exec'd program, remove any
820 If there are breakpoints, they aren't really inserted now,
821 since the exec() transformed our inferior into a fresh set
824 We want to preserve symbolic breakpoints on the list, since
825 we have hopes that they can be reset after the new a.out's
826 symbol table is read.
828 However, any "raw" breakpoints must be removed from the list
829 (e.g., the solib bp's), since their address is probably invalid
832 And, we DON'T want to call delete_breakpoints() here, since
833 that may write the bp's "shadow contents" (the instruction
834 value that was overwritten witha TRAP instruction). Since
835 we now have a new a.out, those shadow contents aren't valid. */
837 mark_breakpoints_out ();
839 update_breakpoints_after_exec ();
841 /* If there was one, it's gone now. We cannot truly step-to-next
842 statement through an exec(). */
843 th
->control
.step_resume_breakpoint
= NULL
;
844 th
->control
.exception_resume_breakpoint
= NULL
;
845 th
->control
.step_range_start
= 0;
846 th
->control
.step_range_end
= 0;
848 /* The target reports the exec event to the main thread, even if
849 some other thread does the exec, and even if the main thread was
850 already stopped --- if debugging in non-stop mode, it's possible
851 the user had the main thread held stopped in the previous image
852 --- release it now. This is the same behavior as step-over-exec
853 with scheduler-locking on in all-stop mode. */
854 th
->stop_requested
= 0;
856 /* What is this a.out's name? */
857 printf_unfiltered (_("%s is executing new program: %s\n"),
858 target_pid_to_str (inferior_ptid
),
861 /* We've followed the inferior through an exec. Therefore, the
862 inferior has essentially been killed & reborn. */
864 gdb_flush (gdb_stdout
);
866 breakpoint_init_inferior (inf_execd
);
868 if (gdb_sysroot
&& *gdb_sysroot
)
870 char *name
= alloca (strlen (gdb_sysroot
)
871 + strlen (execd_pathname
)
874 strcpy (name
, gdb_sysroot
);
875 strcat (name
, execd_pathname
);
876 execd_pathname
= name
;
879 /* Reset the shared library package. This ensures that we get a
880 shlib event when the child reaches "_start", at which point the
881 dld will have had a chance to initialize the child. */
882 /* Also, loading a symbol file below may trigger symbol lookups, and
883 we don't want those to be satisfied by the libraries of the
884 previous incarnation of this process. */
885 no_shared_libraries (NULL
, 0);
887 if (follow_exec_mode_string
== follow_exec_mode_new
)
889 struct program_space
*pspace
;
891 /* The user wants to keep the old inferior and program spaces
892 around. Create a new fresh one, and switch to it. */
894 inf
= add_inferior (current_inferior ()->pid
);
895 pspace
= add_program_space (maybe_new_address_space ());
896 inf
->pspace
= pspace
;
897 inf
->aspace
= pspace
->aspace
;
899 exit_inferior_num_silent (current_inferior ()->num
);
901 set_current_inferior (inf
);
902 set_current_program_space (pspace
);
905 gdb_assert (current_program_space
== inf
->pspace
);
907 /* That a.out is now the one to use. */
908 exec_file_attach (execd_pathname
, 0);
910 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
911 (Position Independent Executable) main symbol file will get applied by
912 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
913 the breakpoints with the zero displacement. */
915 symbol_file_add (execd_pathname
,
917 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
920 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
921 set_initial_language ();
923 #ifdef SOLIB_CREATE_INFERIOR_HOOK
924 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid
));
926 solib_create_inferior_hook (0);
929 jit_inferior_created_hook ();
931 breakpoint_re_set ();
933 /* Reinsert all breakpoints. (Those which were symbolic have
934 been reset to the proper address in the new a.out, thanks
935 to symbol_file_command...). */
936 insert_breakpoints ();
938 /* The next resume of this inferior should bring it to the shlib
939 startup breakpoints. (If the user had also set bp's on
940 "main" from the old (parent) process, then they'll auto-
941 matically get reset there in the new process.). */
944 /* Non-zero if we just simulating a single-step. This is needed
945 because we cannot remove the breakpoints in the inferior process
946 until after the `wait' in `wait_for_inferior'. */
947 static int singlestep_breakpoints_inserted_p
= 0;
949 /* The thread we inserted single-step breakpoints for. */
950 static ptid_t singlestep_ptid
;
952 /* PC when we started this single-step. */
953 static CORE_ADDR singlestep_pc
;
955 /* If another thread hit the singlestep breakpoint, we save the original
956 thread here so that we can resume single-stepping it later. */
957 static ptid_t saved_singlestep_ptid
;
958 static int stepping_past_singlestep_breakpoint
;
960 /* If not equal to null_ptid, this means that after stepping over breakpoint
961 is finished, we need to switch to deferred_step_ptid, and step it.
963 The use case is when one thread has hit a breakpoint, and then the user
964 has switched to another thread and issued 'step'. We need to step over
965 breakpoint in the thread which hit the breakpoint, but then continue
966 stepping the thread user has selected. */
967 static ptid_t deferred_step_ptid
;
969 /* Displaced stepping. */
971 /* In non-stop debugging mode, we must take special care to manage
972 breakpoints properly; in particular, the traditional strategy for
973 stepping a thread past a breakpoint it has hit is unsuitable.
974 'Displaced stepping' is a tactic for stepping one thread past a
975 breakpoint it has hit while ensuring that other threads running
976 concurrently will hit the breakpoint as they should.
978 The traditional way to step a thread T off a breakpoint in a
979 multi-threaded program in all-stop mode is as follows:
981 a0) Initially, all threads are stopped, and breakpoints are not
983 a1) We single-step T, leaving breakpoints uninserted.
984 a2) We insert breakpoints, and resume all threads.
986 In non-stop debugging, however, this strategy is unsuitable: we
987 don't want to have to stop all threads in the system in order to
988 continue or step T past a breakpoint. Instead, we use displaced
991 n0) Initially, T is stopped, other threads are running, and
992 breakpoints are inserted.
993 n1) We copy the instruction "under" the breakpoint to a separate
994 location, outside the main code stream, making any adjustments
995 to the instruction, register, and memory state as directed by
997 n2) We single-step T over the instruction at its new location.
998 n3) We adjust the resulting register and memory state as directed
999 by T's architecture. This includes resetting T's PC to point
1000 back into the main instruction stream.
1003 This approach depends on the following gdbarch methods:
1005 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1006 indicate where to copy the instruction, and how much space must
1007 be reserved there. We use these in step n1.
1009 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1010 address, and makes any necessary adjustments to the instruction,
1011 register contents, and memory. We use this in step n1.
1013 - gdbarch_displaced_step_fixup adjusts registers and memory after
1014 we have successfuly single-stepped the instruction, to yield the
1015 same effect the instruction would have had if we had executed it
1016 at its original address. We use this in step n3.
1018 - gdbarch_displaced_step_free_closure provides cleanup.
1020 The gdbarch_displaced_step_copy_insn and
1021 gdbarch_displaced_step_fixup functions must be written so that
1022 copying an instruction with gdbarch_displaced_step_copy_insn,
1023 single-stepping across the copied instruction, and then applying
1024 gdbarch_displaced_insn_fixup should have the same effects on the
1025 thread's memory and registers as stepping the instruction in place
1026 would have. Exactly which responsibilities fall to the copy and
1027 which fall to the fixup is up to the author of those functions.
1029 See the comments in gdbarch.sh for details.
1031 Note that displaced stepping and software single-step cannot
1032 currently be used in combination, although with some care I think
1033 they could be made to. Software single-step works by placing
1034 breakpoints on all possible subsequent instructions; if the
1035 displaced instruction is a PC-relative jump, those breakpoints
1036 could fall in very strange places --- on pages that aren't
1037 executable, or at addresses that are not proper instruction
1038 boundaries. (We do generally let other threads run while we wait
1039 to hit the software single-step breakpoint, and they might
1040 encounter such a corrupted instruction.) One way to work around
1041 this would be to have gdbarch_displaced_step_copy_insn fully
1042 simulate the effect of PC-relative instructions (and return NULL)
1043 on architectures that use software single-stepping.
1045 In non-stop mode, we can have independent and simultaneous step
1046 requests, so more than one thread may need to simultaneously step
1047 over a breakpoint. The current implementation assumes there is
1048 only one scratch space per process. In this case, we have to
1049 serialize access to the scratch space. If thread A wants to step
1050 over a breakpoint, but we are currently waiting for some other
1051 thread to complete a displaced step, we leave thread A stopped and
1052 place it in the displaced_step_request_queue. Whenever a displaced
1053 step finishes, we pick the next thread in the queue and start a new
1054 displaced step operation on it. See displaced_step_prepare and
1055 displaced_step_fixup for details. */
1057 struct displaced_step_request
1060 struct displaced_step_request
*next
;
1063 /* Per-inferior displaced stepping state. */
1064 struct displaced_step_inferior_state
1066 /* Pointer to next in linked list. */
1067 struct displaced_step_inferior_state
*next
;
1069 /* The process this displaced step state refers to. */
1072 /* A queue of pending displaced stepping requests. One entry per
1073 thread that needs to do a displaced step. */
1074 struct displaced_step_request
*step_request_queue
;
1076 /* If this is not null_ptid, this is the thread carrying out a
1077 displaced single-step in process PID. This thread's state will
1078 require fixing up once it has completed its step. */
1081 /* The architecture the thread had when we stepped it. */
1082 struct gdbarch
*step_gdbarch
;
1084 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1085 for post-step cleanup. */
1086 struct displaced_step_closure
*step_closure
;
1088 /* The address of the original instruction, and the copy we
1090 CORE_ADDR step_original
, step_copy
;
1092 /* Saved contents of copy area. */
1093 gdb_byte
*step_saved_copy
;
1096 /* The list of states of processes involved in displaced stepping
1098 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1100 /* Get the displaced stepping state of process PID. */
1102 static struct displaced_step_inferior_state
*
1103 get_displaced_stepping_state (int pid
)
1105 struct displaced_step_inferior_state
*state
;
1107 for (state
= displaced_step_inferior_states
;
1109 state
= state
->next
)
1110 if (state
->pid
== pid
)
1116 /* Add a new displaced stepping state for process PID to the displaced
1117 stepping state list, or return a pointer to an already existing
1118 entry, if it already exists. Never returns NULL. */
1120 static struct displaced_step_inferior_state
*
1121 add_displaced_stepping_state (int pid
)
1123 struct displaced_step_inferior_state
*state
;
1125 for (state
= displaced_step_inferior_states
;
1127 state
= state
->next
)
1128 if (state
->pid
== pid
)
1131 state
= xcalloc (1, sizeof (*state
));
1133 state
->next
= displaced_step_inferior_states
;
1134 displaced_step_inferior_states
= state
;
1139 /* If inferior is in displaced stepping, and ADDR equals to starting address
1140 of copy area, return corresponding displaced_step_closure. Otherwise,
1143 struct displaced_step_closure
*
1144 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1146 struct displaced_step_inferior_state
*displaced
1147 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1149 /* If checking the mode of displaced instruction in copy area. */
1150 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1151 && (displaced
->step_copy
== addr
))
1152 return displaced
->step_closure
;
1157 /* Remove the displaced stepping state of process PID. */
1160 remove_displaced_stepping_state (int pid
)
1162 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1164 gdb_assert (pid
!= 0);
1166 it
= displaced_step_inferior_states
;
1167 prev_next_p
= &displaced_step_inferior_states
;
1172 *prev_next_p
= it
->next
;
1177 prev_next_p
= &it
->next
;
1183 infrun_inferior_exit (struct inferior
*inf
)
1185 remove_displaced_stepping_state (inf
->pid
);
1188 /* Enum strings for "set|show displaced-stepping". */
1190 static const char can_use_displaced_stepping_auto
[] = "auto";
1191 static const char can_use_displaced_stepping_on
[] = "on";
1192 static const char can_use_displaced_stepping_off
[] = "off";
1193 static const char *const can_use_displaced_stepping_enum
[] =
1195 can_use_displaced_stepping_auto
,
1196 can_use_displaced_stepping_on
,
1197 can_use_displaced_stepping_off
,
1201 /* If ON, and the architecture supports it, GDB will use displaced
1202 stepping to step over breakpoints. If OFF, or if the architecture
1203 doesn't support it, GDB will instead use the traditional
1204 hold-and-step approach. If AUTO (which is the default), GDB will
1205 decide which technique to use to step over breakpoints depending on
1206 which of all-stop or non-stop mode is active --- displaced stepping
1207 in non-stop mode; hold-and-step in all-stop mode. */
1209 static const char *can_use_displaced_stepping
=
1210 can_use_displaced_stepping_auto
;
1213 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1214 struct cmd_list_element
*c
,
1217 if (can_use_displaced_stepping
== can_use_displaced_stepping_auto
)
1218 fprintf_filtered (file
,
1219 _("Debugger's willingness to use displaced stepping "
1220 "to step over breakpoints is %s (currently %s).\n"),
1221 value
, non_stop
? "on" : "off");
1223 fprintf_filtered (file
,
1224 _("Debugger's willingness to use displaced stepping "
1225 "to step over breakpoints is %s.\n"), value
);
1228 /* Return non-zero if displaced stepping can/should be used to step
1229 over breakpoints. */
1232 use_displaced_stepping (struct gdbarch
*gdbarch
)
1234 return (((can_use_displaced_stepping
== can_use_displaced_stepping_auto
1236 || can_use_displaced_stepping
== can_use_displaced_stepping_on
)
1237 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1238 && !RECORD_IS_USED
);
1241 /* Clean out any stray displaced stepping state. */
1243 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1245 /* Indicate that there is no cleanup pending. */
1246 displaced
->step_ptid
= null_ptid
;
1248 if (displaced
->step_closure
)
1250 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1251 displaced
->step_closure
);
1252 displaced
->step_closure
= NULL
;
1257 displaced_step_clear_cleanup (void *arg
)
1259 struct displaced_step_inferior_state
*state
= arg
;
1261 displaced_step_clear (state
);
1264 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1266 displaced_step_dump_bytes (struct ui_file
*file
,
1267 const gdb_byte
*buf
,
1272 for (i
= 0; i
< len
; i
++)
1273 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1274 fputs_unfiltered ("\n", file
);
1277 /* Prepare to single-step, using displaced stepping.
1279 Note that we cannot use displaced stepping when we have a signal to
1280 deliver. If we have a signal to deliver and an instruction to step
1281 over, then after the step, there will be no indication from the
1282 target whether the thread entered a signal handler or ignored the
1283 signal and stepped over the instruction successfully --- both cases
1284 result in a simple SIGTRAP. In the first case we mustn't do a
1285 fixup, and in the second case we must --- but we can't tell which.
1286 Comments in the code for 'random signals' in handle_inferior_event
1287 explain how we handle this case instead.
1289 Returns 1 if preparing was successful -- this thread is going to be
1290 stepped now; or 0 if displaced stepping this thread got queued. */
1292 displaced_step_prepare (ptid_t ptid
)
1294 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1295 struct regcache
*regcache
= get_thread_regcache (ptid
);
1296 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1297 CORE_ADDR original
, copy
;
1299 struct displaced_step_closure
*closure
;
1300 struct displaced_step_inferior_state
*displaced
;
1303 /* We should never reach this function if the architecture does not
1304 support displaced stepping. */
1305 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1307 /* We have to displaced step one thread at a time, as we only have
1308 access to a single scratch space per inferior. */
1310 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1312 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1314 /* Already waiting for a displaced step to finish. Defer this
1315 request and place in queue. */
1316 struct displaced_step_request
*req
, *new_req
;
1318 if (debug_displaced
)
1319 fprintf_unfiltered (gdb_stdlog
,
1320 "displaced: defering step of %s\n",
1321 target_pid_to_str (ptid
));
1323 new_req
= xmalloc (sizeof (*new_req
));
1324 new_req
->ptid
= ptid
;
1325 new_req
->next
= NULL
;
1327 if (displaced
->step_request_queue
)
1329 for (req
= displaced
->step_request_queue
;
1333 req
->next
= new_req
;
1336 displaced
->step_request_queue
= new_req
;
1342 if (debug_displaced
)
1343 fprintf_unfiltered (gdb_stdlog
,
1344 "displaced: stepping %s now\n",
1345 target_pid_to_str (ptid
));
1348 displaced_step_clear (displaced
);
1350 old_cleanups
= save_inferior_ptid ();
1351 inferior_ptid
= ptid
;
1353 original
= regcache_read_pc (regcache
);
1355 copy
= gdbarch_displaced_step_location (gdbarch
);
1356 len
= gdbarch_max_insn_length (gdbarch
);
1358 /* Save the original contents of the copy area. */
1359 displaced
->step_saved_copy
= xmalloc (len
);
1360 ignore_cleanups
= make_cleanup (free_current_contents
,
1361 &displaced
->step_saved_copy
);
1362 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1364 throw_error (MEMORY_ERROR
,
1365 _("Error accessing memory address %s (%s) for "
1366 "displaced-stepping scratch space."),
1367 paddress (gdbarch
, copy
), safe_strerror (status
));
1368 if (debug_displaced
)
1370 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1371 paddress (gdbarch
, copy
));
1372 displaced_step_dump_bytes (gdb_stdlog
,
1373 displaced
->step_saved_copy
,
1377 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1378 original
, copy
, regcache
);
1380 /* We don't support the fully-simulated case at present. */
1381 gdb_assert (closure
);
1383 /* Save the information we need to fix things up if the step
1385 displaced
->step_ptid
= ptid
;
1386 displaced
->step_gdbarch
= gdbarch
;
1387 displaced
->step_closure
= closure
;
1388 displaced
->step_original
= original
;
1389 displaced
->step_copy
= copy
;
1391 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1393 /* Resume execution at the copy. */
1394 regcache_write_pc (regcache
, copy
);
1396 discard_cleanups (ignore_cleanups
);
1398 do_cleanups (old_cleanups
);
1400 if (debug_displaced
)
1401 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1402 paddress (gdbarch
, copy
));
1408 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1409 const gdb_byte
*myaddr
, int len
)
1411 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1413 inferior_ptid
= ptid
;
1414 write_memory (memaddr
, myaddr
, len
);
1415 do_cleanups (ptid_cleanup
);
1418 /* Restore the contents of the copy area for thread PTID. */
1421 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1424 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1426 write_memory_ptid (ptid
, displaced
->step_copy
,
1427 displaced
->step_saved_copy
, len
);
1428 if (debug_displaced
)
1429 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1430 target_pid_to_str (ptid
),
1431 paddress (displaced
->step_gdbarch
,
1432 displaced
->step_copy
));
1436 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1438 struct cleanup
*old_cleanups
;
1439 struct displaced_step_inferior_state
*displaced
1440 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1442 /* Was any thread of this process doing a displaced step? */
1443 if (displaced
== NULL
)
1446 /* Was this event for the pid we displaced? */
1447 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1448 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1451 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1453 displaced_step_restore (displaced
, displaced
->step_ptid
);
1455 /* Did the instruction complete successfully? */
1456 if (signal
== GDB_SIGNAL_TRAP
)
1458 /* Fix up the resulting state. */
1459 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1460 displaced
->step_closure
,
1461 displaced
->step_original
,
1462 displaced
->step_copy
,
1463 get_thread_regcache (displaced
->step_ptid
));
1467 /* Since the instruction didn't complete, all we can do is
1469 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1470 CORE_ADDR pc
= regcache_read_pc (regcache
);
1472 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1473 regcache_write_pc (regcache
, pc
);
1476 do_cleanups (old_cleanups
);
1478 displaced
->step_ptid
= null_ptid
;
1480 /* Are there any pending displaced stepping requests? If so, run
1481 one now. Leave the state object around, since we're likely to
1482 need it again soon. */
1483 while (displaced
->step_request_queue
)
1485 struct displaced_step_request
*head
;
1487 struct regcache
*regcache
;
1488 struct gdbarch
*gdbarch
;
1489 CORE_ADDR actual_pc
;
1490 struct address_space
*aspace
;
1492 head
= displaced
->step_request_queue
;
1494 displaced
->step_request_queue
= head
->next
;
1497 context_switch (ptid
);
1499 regcache
= get_thread_regcache (ptid
);
1500 actual_pc
= regcache_read_pc (regcache
);
1501 aspace
= get_regcache_aspace (regcache
);
1503 if (breakpoint_here_p (aspace
, actual_pc
))
1505 if (debug_displaced
)
1506 fprintf_unfiltered (gdb_stdlog
,
1507 "displaced: stepping queued %s now\n",
1508 target_pid_to_str (ptid
));
1510 displaced_step_prepare (ptid
);
1512 gdbarch
= get_regcache_arch (regcache
);
1514 if (debug_displaced
)
1516 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
1519 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1520 paddress (gdbarch
, actual_pc
));
1521 read_memory (actual_pc
, buf
, sizeof (buf
));
1522 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1525 if (gdbarch_displaced_step_hw_singlestep (gdbarch
,
1526 displaced
->step_closure
))
1527 target_resume (ptid
, 1, GDB_SIGNAL_0
);
1529 target_resume (ptid
, 0, GDB_SIGNAL_0
);
1531 /* Done, we're stepping a thread. */
1537 struct thread_info
*tp
= inferior_thread ();
1539 /* The breakpoint we were sitting under has since been
1541 tp
->control
.trap_expected
= 0;
1543 /* Go back to what we were trying to do. */
1544 step
= currently_stepping (tp
);
1546 if (debug_displaced
)
1547 fprintf_unfiltered (gdb_stdlog
,
1548 "displaced: breakpoint is gone: %s, step(%d)\n",
1549 target_pid_to_str (tp
->ptid
), step
);
1551 target_resume (ptid
, step
, GDB_SIGNAL_0
);
1552 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1554 /* This request was discarded. See if there's any other
1555 thread waiting for its turn. */
1560 /* Update global variables holding ptids to hold NEW_PTID if they were
1561 holding OLD_PTID. */
1563 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1565 struct displaced_step_request
*it
;
1566 struct displaced_step_inferior_state
*displaced
;
1568 if (ptid_equal (inferior_ptid
, old_ptid
))
1569 inferior_ptid
= new_ptid
;
1571 if (ptid_equal (singlestep_ptid
, old_ptid
))
1572 singlestep_ptid
= new_ptid
;
1574 if (ptid_equal (deferred_step_ptid
, old_ptid
))
1575 deferred_step_ptid
= new_ptid
;
1577 for (displaced
= displaced_step_inferior_states
;
1579 displaced
= displaced
->next
)
1581 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
1582 displaced
->step_ptid
= new_ptid
;
1584 for (it
= displaced
->step_request_queue
; it
; it
= it
->next
)
1585 if (ptid_equal (it
->ptid
, old_ptid
))
1586 it
->ptid
= new_ptid
;
1593 /* Things to clean up if we QUIT out of resume (). */
1595 resume_cleanups (void *ignore
)
1600 static const char schedlock_off
[] = "off";
1601 static const char schedlock_on
[] = "on";
1602 static const char schedlock_step
[] = "step";
1603 static const char *const scheduler_enums
[] = {
1609 static const char *scheduler_mode
= schedlock_off
;
1611 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1612 struct cmd_list_element
*c
, const char *value
)
1614 fprintf_filtered (file
,
1615 _("Mode for locking scheduler "
1616 "during execution is \"%s\".\n"),
1621 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1623 if (!target_can_lock_scheduler
)
1625 scheduler_mode
= schedlock_off
;
1626 error (_("Target '%s' cannot support this command."), target_shortname
);
1630 /* True if execution commands resume all threads of all processes by
1631 default; otherwise, resume only threads of the current inferior
1633 int sched_multi
= 0;
1635 /* Try to setup for software single stepping over the specified location.
1636 Return 1 if target_resume() should use hardware single step.
1638 GDBARCH the current gdbarch.
1639 PC the location to step over. */
1642 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1646 if (execution_direction
== EXEC_FORWARD
1647 && gdbarch_software_single_step_p (gdbarch
)
1648 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1651 /* Do not pull these breakpoints until after a `wait' in
1652 `wait_for_inferior'. */
1653 singlestep_breakpoints_inserted_p
= 1;
1654 singlestep_ptid
= inferior_ptid
;
1660 /* Return a ptid representing the set of threads that we will proceed,
1661 in the perspective of the user/frontend. We may actually resume
1662 fewer threads at first, e.g., if a thread is stopped at a
1663 breakpoint that needs stepping-off, but that should not be visible
1664 to the user/frontend, and neither should the frontend/user be
1665 allowed to proceed any of the threads that happen to be stopped for
1666 internal run control handling, if a previous command wanted them
1670 user_visible_resume_ptid (int step
)
1672 /* By default, resume all threads of all processes. */
1673 ptid_t resume_ptid
= RESUME_ALL
;
1675 /* Maybe resume only all threads of the current process. */
1676 if (!sched_multi
&& target_supports_multi_process ())
1678 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
1681 /* Maybe resume a single thread after all. */
1684 /* With non-stop mode on, threads are always handled
1686 resume_ptid
= inferior_ptid
;
1688 else if ((scheduler_mode
== schedlock_on
)
1689 || (scheduler_mode
== schedlock_step
1690 && (step
|| singlestep_breakpoints_inserted_p
)))
1692 /* User-settable 'scheduler' mode requires solo thread resume. */
1693 resume_ptid
= inferior_ptid
;
1699 /* Resume the inferior, but allow a QUIT. This is useful if the user
1700 wants to interrupt some lengthy single-stepping operation
1701 (for child processes, the SIGINT goes to the inferior, and so
1702 we get a SIGINT random_signal, but for remote debugging and perhaps
1703 other targets, that's not true).
1705 STEP nonzero if we should step (zero to continue instead).
1706 SIG is the signal to give the inferior (zero for none). */
1708 resume (int step
, enum gdb_signal sig
)
1710 int should_resume
= 1;
1711 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
1712 struct regcache
*regcache
= get_current_regcache ();
1713 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1714 struct thread_info
*tp
= inferior_thread ();
1715 CORE_ADDR pc
= regcache_read_pc (regcache
);
1716 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1720 if (current_inferior ()->waiting_for_vfork_done
)
1722 /* Don't try to single-step a vfork parent that is waiting for
1723 the child to get out of the shared memory region (by exec'ing
1724 or exiting). This is particularly important on software
1725 single-step archs, as the child process would trip on the
1726 software single step breakpoint inserted for the parent
1727 process. Since the parent will not actually execute any
1728 instruction until the child is out of the shared region (such
1729 are vfork's semantics), it is safe to simply continue it.
1730 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
1731 the parent, and tell it to `keep_going', which automatically
1732 re-sets it stepping. */
1734 fprintf_unfiltered (gdb_stdlog
,
1735 "infrun: resume : clear step\n");
1740 fprintf_unfiltered (gdb_stdlog
,
1741 "infrun: resume (step=%d, signal=%d), "
1742 "trap_expected=%d, current thread [%s] at %s\n",
1743 step
, sig
, tp
->control
.trap_expected
,
1744 target_pid_to_str (inferior_ptid
),
1745 paddress (gdbarch
, pc
));
1747 /* Normally, by the time we reach `resume', the breakpoints are either
1748 removed or inserted, as appropriate. The exception is if we're sitting
1749 at a permanent breakpoint; we need to step over it, but permanent
1750 breakpoints can't be removed. So we have to test for it here. */
1751 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
1753 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
1754 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
1757 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1758 how to step past a permanent breakpoint on this architecture. Try using\n\
1759 a command like `return' or `jump' to continue execution."));
1762 /* If enabled, step over breakpoints by executing a copy of the
1763 instruction at a different address.
1765 We can't use displaced stepping when we have a signal to deliver;
1766 the comments for displaced_step_prepare explain why. The
1767 comments in the handle_inferior event for dealing with 'random
1768 signals' explain what we do instead.
1770 We can't use displaced stepping when we are waiting for vfork_done
1771 event, displaced stepping breaks the vfork child similarly as single
1772 step software breakpoint. */
1773 if (use_displaced_stepping (gdbarch
)
1774 && (tp
->control
.trap_expected
1775 || (step
&& gdbarch_software_single_step_p (gdbarch
)))
1776 && sig
== GDB_SIGNAL_0
1777 && !current_inferior ()->waiting_for_vfork_done
)
1779 struct displaced_step_inferior_state
*displaced
;
1781 if (!displaced_step_prepare (inferior_ptid
))
1783 /* Got placed in displaced stepping queue. Will be resumed
1784 later when all the currently queued displaced stepping
1785 requests finish. The thread is not executing at this point,
1786 and the call to set_executing will be made later. But we
1787 need to call set_running here, since from frontend point of view,
1788 the thread is running. */
1789 set_running (inferior_ptid
, 1);
1790 discard_cleanups (old_cleanups
);
1794 /* Update pc to reflect the new address from which we will execute
1795 instructions due to displaced stepping. */
1796 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
1798 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1799 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
1800 displaced
->step_closure
);
1803 /* Do we need to do it the hard way, w/temp breakpoints? */
1805 step
= maybe_software_singlestep (gdbarch
, pc
);
1807 /* Currently, our software single-step implementation leads to different
1808 results than hardware single-stepping in one situation: when stepping
1809 into delivering a signal which has an associated signal handler,
1810 hardware single-step will stop at the first instruction of the handler,
1811 while software single-step will simply skip execution of the handler.
1813 For now, this difference in behavior is accepted since there is no
1814 easy way to actually implement single-stepping into a signal handler
1815 without kernel support.
1817 However, there is one scenario where this difference leads to follow-on
1818 problems: if we're stepping off a breakpoint by removing all breakpoints
1819 and then single-stepping. In this case, the software single-step
1820 behavior means that even if there is a *breakpoint* in the signal
1821 handler, GDB still would not stop.
1823 Fortunately, we can at least fix this particular issue. We detect
1824 here the case where we are about to deliver a signal while software
1825 single-stepping with breakpoints removed. In this situation, we
1826 revert the decisions to remove all breakpoints and insert single-
1827 step breakpoints, and instead we install a step-resume breakpoint
1828 at the current address, deliver the signal without stepping, and
1829 once we arrive back at the step-resume breakpoint, actually step
1830 over the breakpoint we originally wanted to step over. */
1831 if (singlestep_breakpoints_inserted_p
1832 && tp
->control
.trap_expected
&& sig
!= GDB_SIGNAL_0
)
1834 /* If we have nested signals or a pending signal is delivered
1835 immediately after a handler returns, might might already have
1836 a step-resume breakpoint set on the earlier handler. We cannot
1837 set another step-resume breakpoint; just continue on until the
1838 original breakpoint is hit. */
1839 if (tp
->control
.step_resume_breakpoint
== NULL
)
1841 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
1842 tp
->step_after_step_resume_breakpoint
= 1;
1845 remove_single_step_breakpoints ();
1846 singlestep_breakpoints_inserted_p
= 0;
1848 insert_breakpoints ();
1849 tp
->control
.trap_expected
= 0;
1856 /* If STEP is set, it's a request to use hardware stepping
1857 facilities. But in that case, we should never
1858 use singlestep breakpoint. */
1859 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1861 /* Decide the set of threads to ask the target to resume. Start
1862 by assuming everything will be resumed, than narrow the set
1863 by applying increasingly restricting conditions. */
1864 resume_ptid
= user_visible_resume_ptid (step
);
1866 /* Maybe resume a single thread after all. */
1867 if (singlestep_breakpoints_inserted_p
1868 && stepping_past_singlestep_breakpoint
)
1870 /* The situation here is as follows. In thread T1 we wanted to
1871 single-step. Lacking hardware single-stepping we've
1872 set breakpoint at the PC of the next instruction -- call it
1873 P. After resuming, we've hit that breakpoint in thread T2.
1874 Now we've removed original breakpoint, inserted breakpoint
1875 at P+1, and try to step to advance T2 past breakpoint.
1876 We need to step only T2, as if T1 is allowed to freely run,
1877 it can run past P, and if other threads are allowed to run,
1878 they can hit breakpoint at P+1, and nested hits of single-step
1879 breakpoints is not something we'd want -- that's complicated
1880 to support, and has no value. */
1881 resume_ptid
= inferior_ptid
;
1883 else if ((step
|| singlestep_breakpoints_inserted_p
)
1884 && tp
->control
.trap_expected
)
1886 /* We're allowing a thread to run past a breakpoint it has
1887 hit, by single-stepping the thread with the breakpoint
1888 removed. In which case, we need to single-step only this
1889 thread, and keep others stopped, as they can miss this
1890 breakpoint if allowed to run.
1892 The current code actually removes all breakpoints when
1893 doing this, not just the one being stepped over, so if we
1894 let other threads run, we can actually miss any
1895 breakpoint, not just the one at PC. */
1896 resume_ptid
= inferior_ptid
;
1899 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1901 /* Most targets can step a breakpoint instruction, thus
1902 executing it normally. But if this one cannot, just
1903 continue and we will hit it anyway. */
1904 if (step
&& breakpoint_inserted_here_p (aspace
, pc
))
1909 && use_displaced_stepping (gdbarch
)
1910 && tp
->control
.trap_expected
)
1912 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1913 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
1914 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1917 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1918 paddress (resume_gdbarch
, actual_pc
));
1919 read_memory (actual_pc
, buf
, sizeof (buf
));
1920 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1923 /* Install inferior's terminal modes. */
1924 target_terminal_inferior ();
1926 /* Avoid confusing the next resume, if the next stop/resume
1927 happens to apply to another thread. */
1928 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1930 /* Advise target which signals may be handled silently. If we have
1931 removed breakpoints because we are stepping over one (which can
1932 happen only if we are not using displaced stepping), we need to
1933 receive all signals to avoid accidentally skipping a breakpoint
1934 during execution of a signal handler. */
1935 if ((step
|| singlestep_breakpoints_inserted_p
)
1936 && tp
->control
.trap_expected
1937 && !use_displaced_stepping (gdbarch
))
1938 target_pass_signals (0, NULL
);
1940 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
1942 target_resume (resume_ptid
, step
, sig
);
1945 discard_cleanups (old_cleanups
);
1950 /* Clear out all variables saying what to do when inferior is continued.
1951 First do this, then set the ones you want, then call `proceed'. */
1954 clear_proceed_status_thread (struct thread_info
*tp
)
1957 fprintf_unfiltered (gdb_stdlog
,
1958 "infrun: clear_proceed_status_thread (%s)\n",
1959 target_pid_to_str (tp
->ptid
));
1961 tp
->control
.trap_expected
= 0;
1962 tp
->control
.step_range_start
= 0;
1963 tp
->control
.step_range_end
= 0;
1964 tp
->control
.step_frame_id
= null_frame_id
;
1965 tp
->control
.step_stack_frame_id
= null_frame_id
;
1966 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1967 tp
->stop_requested
= 0;
1969 tp
->control
.stop_step
= 0;
1971 tp
->control
.proceed_to_finish
= 0;
1973 /* Discard any remaining commands or status from previous stop. */
1974 bpstat_clear (&tp
->control
.stop_bpstat
);
1978 clear_proceed_status_callback (struct thread_info
*tp
, void *data
)
1980 if (is_exited (tp
->ptid
))
1983 clear_proceed_status_thread (tp
);
1988 clear_proceed_status (void)
1992 /* In all-stop mode, delete the per-thread status of all
1993 threads, even if inferior_ptid is null_ptid, there may be
1994 threads on the list. E.g., we may be launching a new
1995 process, while selecting the executable. */
1996 iterate_over_threads (clear_proceed_status_callback
, NULL
);
1999 if (!ptid_equal (inferior_ptid
, null_ptid
))
2001 struct inferior
*inferior
;
2005 /* If in non-stop mode, only delete the per-thread status of
2006 the current thread. */
2007 clear_proceed_status_thread (inferior_thread ());
2010 inferior
= current_inferior ();
2011 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2014 stop_after_trap
= 0;
2016 observer_notify_about_to_proceed ();
2020 regcache_xfree (stop_registers
);
2021 stop_registers
= NULL
;
2025 /* Check the current thread against the thread that reported the most recent
2026 event. If a step-over is required return TRUE and set the current thread
2027 to the old thread. Otherwise return FALSE.
2029 This should be suitable for any targets that support threads. */
2032 prepare_to_proceed (int step
)
2035 struct target_waitstatus wait_status
;
2036 int schedlock_enabled
;
2038 /* With non-stop mode on, threads are always handled individually. */
2039 gdb_assert (! non_stop
);
2041 /* Get the last target status returned by target_wait(). */
2042 get_last_target_status (&wait_ptid
, &wait_status
);
2044 /* Make sure we were stopped at a breakpoint. */
2045 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
2046 || (wait_status
.value
.sig
!= GDB_SIGNAL_TRAP
2047 && wait_status
.value
.sig
!= GDB_SIGNAL_ILL
2048 && wait_status
.value
.sig
!= GDB_SIGNAL_SEGV
2049 && wait_status
.value
.sig
!= GDB_SIGNAL_EMT
))
2054 schedlock_enabled
= (scheduler_mode
== schedlock_on
2055 || (scheduler_mode
== schedlock_step
2058 /* Don't switch over to WAIT_PTID if scheduler locking is on. */
2059 if (schedlock_enabled
)
2062 /* Don't switch over if we're about to resume some other process
2063 other than WAIT_PTID's, and schedule-multiple is off. */
2065 && ptid_get_pid (wait_ptid
) != ptid_get_pid (inferior_ptid
))
2068 /* Switched over from WAIT_PID. */
2069 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
2070 && !ptid_equal (inferior_ptid
, wait_ptid
))
2072 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
2074 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2075 regcache_read_pc (regcache
)))
2077 /* If stepping, remember current thread to switch back to. */
2079 deferred_step_ptid
= inferior_ptid
;
2081 /* Switch back to WAIT_PID thread. */
2082 switch_to_thread (wait_ptid
);
2085 fprintf_unfiltered (gdb_stdlog
,
2086 "infrun: prepare_to_proceed (step=%d), "
2087 "switched to [%s]\n",
2088 step
, target_pid_to_str (inferior_ptid
));
2090 /* We return 1 to indicate that there is a breakpoint here,
2091 so we need to step over it before continuing to avoid
2092 hitting it straight away. */
2100 /* Basic routine for continuing the program in various fashions.
2102 ADDR is the address to resume at, or -1 for resume where stopped.
2103 SIGGNAL is the signal to give it, or 0 for none,
2104 or -1 for act according to how it stopped.
2105 STEP is nonzero if should trap after one instruction.
2106 -1 means return after that and print nothing.
2107 You should probably set various step_... variables
2108 before calling here, if you are stepping.
2110 You should call clear_proceed_status before calling proceed. */
2113 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
, int step
)
2115 struct regcache
*regcache
;
2116 struct gdbarch
*gdbarch
;
2117 struct thread_info
*tp
;
2119 struct address_space
*aspace
;
2122 /* If we're stopped at a fork/vfork, follow the branch set by the
2123 "set follow-fork-mode" command; otherwise, we'll just proceed
2124 resuming the current thread. */
2125 if (!follow_fork ())
2127 /* The target for some reason decided not to resume. */
2129 if (target_can_async_p ())
2130 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2134 /* We'll update this if & when we switch to a new thread. */
2135 previous_inferior_ptid
= inferior_ptid
;
2137 regcache
= get_current_regcache ();
2138 gdbarch
= get_regcache_arch (regcache
);
2139 aspace
= get_regcache_aspace (regcache
);
2140 pc
= regcache_read_pc (regcache
);
2143 step_start_function
= find_pc_function (pc
);
2145 stop_after_trap
= 1;
2147 if (addr
== (CORE_ADDR
) -1)
2149 if (pc
== stop_pc
&& breakpoint_here_p (aspace
, pc
)
2150 && execution_direction
!= EXEC_REVERSE
)
2151 /* There is a breakpoint at the address we will resume at,
2152 step one instruction before inserting breakpoints so that
2153 we do not stop right away (and report a second hit at this
2156 Note, we don't do this in reverse, because we won't
2157 actually be executing the breakpoint insn anyway.
2158 We'll be (un-)executing the previous instruction. */
2161 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2162 && gdbarch_single_step_through_delay (gdbarch
,
2163 get_current_frame ()))
2164 /* We stepped onto an instruction that needs to be stepped
2165 again before re-inserting the breakpoint, do so. */
2170 regcache_write_pc (regcache
, addr
);
2174 fprintf_unfiltered (gdb_stdlog
,
2175 "infrun: proceed (addr=%s, signal=%d, step=%d)\n",
2176 paddress (gdbarch
, addr
), siggnal
, step
);
2179 /* In non-stop, each thread is handled individually. The context
2180 must already be set to the right thread here. */
2184 /* In a multi-threaded task we may select another thread and
2185 then continue or step.
2187 But if the old thread was stopped at a breakpoint, it will
2188 immediately cause another breakpoint stop without any
2189 execution (i.e. it will report a breakpoint hit incorrectly).
2190 So we must step over it first.
2192 prepare_to_proceed checks the current thread against the
2193 thread that reported the most recent event. If a step-over
2194 is required it returns TRUE and sets the current thread to
2196 if (prepare_to_proceed (step
))
2200 /* prepare_to_proceed may change the current thread. */
2201 tp
= inferior_thread ();
2205 tp
->control
.trap_expected
= 1;
2206 /* If displaced stepping is enabled, we can step over the
2207 breakpoint without hitting it, so leave all breakpoints
2208 inserted. Otherwise we need to disable all breakpoints, step
2209 one instruction, and then re-add them when that step is
2211 if (!use_displaced_stepping (gdbarch
))
2212 remove_breakpoints ();
2215 /* We can insert breakpoints if we're not trying to step over one,
2216 or if we are stepping over one but we're using displaced stepping
2218 if (! tp
->control
.trap_expected
|| use_displaced_stepping (gdbarch
))
2219 insert_breakpoints ();
2223 /* Pass the last stop signal to the thread we're resuming,
2224 irrespective of whether the current thread is the thread that
2225 got the last event or not. This was historically GDB's
2226 behaviour before keeping a stop_signal per thread. */
2228 struct thread_info
*last_thread
;
2230 struct target_waitstatus last_status
;
2232 get_last_target_status (&last_ptid
, &last_status
);
2233 if (!ptid_equal (inferior_ptid
, last_ptid
)
2234 && !ptid_equal (last_ptid
, null_ptid
)
2235 && !ptid_equal (last_ptid
, minus_one_ptid
))
2237 last_thread
= find_thread_ptid (last_ptid
);
2240 tp
->suspend
.stop_signal
= last_thread
->suspend
.stop_signal
;
2241 last_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2246 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2247 tp
->suspend
.stop_signal
= siggnal
;
2248 /* If this signal should not be seen by program,
2249 give it zero. Used for debugging signals. */
2250 else if (!signal_program
[tp
->suspend
.stop_signal
])
2251 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2253 annotate_starting ();
2255 /* Make sure that output from GDB appears before output from the
2257 gdb_flush (gdb_stdout
);
2259 /* Refresh prev_pc value just prior to resuming. This used to be
2260 done in stop_stepping, however, setting prev_pc there did not handle
2261 scenarios such as inferior function calls or returning from
2262 a function via the return command. In those cases, the prev_pc
2263 value was not set properly for subsequent commands. The prev_pc value
2264 is used to initialize the starting line number in the ecs. With an
2265 invalid value, the gdb next command ends up stopping at the position
2266 represented by the next line table entry past our start position.
2267 On platforms that generate one line table entry per line, this
2268 is not a problem. However, on the ia64, the compiler generates
2269 extraneous line table entries that do not increase the line number.
2270 When we issue the gdb next command on the ia64 after an inferior call
2271 or a return command, we often end up a few instructions forward, still
2272 within the original line we started.
2274 An attempt was made to refresh the prev_pc at the same time the
2275 execution_control_state is initialized (for instance, just before
2276 waiting for an inferior event). But this approach did not work
2277 because of platforms that use ptrace, where the pc register cannot
2278 be read unless the inferior is stopped. At that point, we are not
2279 guaranteed the inferior is stopped and so the regcache_read_pc() call
2280 can fail. Setting the prev_pc value here ensures the value is updated
2281 correctly when the inferior is stopped. */
2282 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2284 /* Fill in with reasonable starting values. */
2285 init_thread_stepping_state (tp
);
2287 /* Reset to normal state. */
2288 init_infwait_state ();
2290 /* Resume inferior. */
2291 resume (oneproc
|| step
|| bpstat_should_step (), tp
->suspend
.stop_signal
);
2293 /* Wait for it to stop (if not standalone)
2294 and in any case decode why it stopped, and act accordingly. */
2295 /* Do this only if we are not using the event loop, or if the target
2296 does not support asynchronous execution. */
2297 if (!target_can_async_p ())
2299 wait_for_inferior ();
2305 /* Start remote-debugging of a machine over a serial link. */
2308 start_remote (int from_tty
)
2310 struct inferior
*inferior
;
2312 inferior
= current_inferior ();
2313 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
2315 /* Always go on waiting for the target, regardless of the mode. */
2316 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2317 indicate to wait_for_inferior that a target should timeout if
2318 nothing is returned (instead of just blocking). Because of this,
2319 targets expecting an immediate response need to, internally, set
2320 things up so that the target_wait() is forced to eventually
2322 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2323 differentiate to its caller what the state of the target is after
2324 the initial open has been performed. Here we're assuming that
2325 the target has stopped. It should be possible to eventually have
2326 target_open() return to the caller an indication that the target
2327 is currently running and GDB state should be set to the same as
2328 for an async run. */
2329 wait_for_inferior ();
2331 /* Now that the inferior has stopped, do any bookkeeping like
2332 loading shared libraries. We want to do this before normal_stop,
2333 so that the displayed frame is up to date. */
2334 post_create_inferior (¤t_target
, from_tty
);
2339 /* Initialize static vars when a new inferior begins. */
2342 init_wait_for_inferior (void)
2344 /* These are meaningless until the first time through wait_for_inferior. */
2346 breakpoint_init_inferior (inf_starting
);
2348 clear_proceed_status ();
2350 stepping_past_singlestep_breakpoint
= 0;
2351 deferred_step_ptid
= null_ptid
;
2353 target_last_wait_ptid
= minus_one_ptid
;
2355 previous_inferior_ptid
= inferior_ptid
;
2356 init_infwait_state ();
2358 /* Discard any skipped inlined frames. */
2359 clear_inline_frame_state (minus_one_ptid
);
2363 /* This enum encodes possible reasons for doing a target_wait, so that
2364 wfi can call target_wait in one place. (Ultimately the call will be
2365 moved out of the infinite loop entirely.) */
2369 infwait_normal_state
,
2370 infwait_thread_hop_state
,
2371 infwait_step_watch_state
,
2372 infwait_nonstep_watch_state
2375 /* The PTID we'll do a target_wait on.*/
2378 /* Current inferior wait state. */
2379 enum infwait_states infwait_state
;
2381 /* Data to be passed around while handling an event. This data is
2382 discarded between events. */
2383 struct execution_control_state
2386 /* The thread that got the event, if this was a thread event; NULL
2388 struct thread_info
*event_thread
;
2390 struct target_waitstatus ws
;
2392 int stop_func_filled_in
;
2393 CORE_ADDR stop_func_start
;
2394 CORE_ADDR stop_func_end
;
2395 const char *stop_func_name
;
2399 static void handle_inferior_event (struct execution_control_state
*ecs
);
2401 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2402 struct execution_control_state
*ecs
);
2403 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2404 struct execution_control_state
*ecs
);
2405 static void check_exception_resume (struct execution_control_state
*,
2406 struct frame_info
*);
2408 static void stop_stepping (struct execution_control_state
*ecs
);
2409 static void prepare_to_wait (struct execution_control_state
*ecs
);
2410 static void keep_going (struct execution_control_state
*ecs
);
2412 /* Callback for iterate over threads. If the thread is stopped, but
2413 the user/frontend doesn't know about that yet, go through
2414 normal_stop, as if the thread had just stopped now. ARG points at
2415 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2416 ptid_is_pid(PTID) is true, applies to all threads of the process
2417 pointed at by PTID. Otherwise, apply only to the thread pointed by
2421 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2423 ptid_t ptid
= * (ptid_t
*) arg
;
2425 if ((ptid_equal (info
->ptid
, ptid
)
2426 || ptid_equal (minus_one_ptid
, ptid
)
2427 || (ptid_is_pid (ptid
)
2428 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2429 && is_running (info
->ptid
)
2430 && !is_executing (info
->ptid
))
2432 struct cleanup
*old_chain
;
2433 struct execution_control_state ecss
;
2434 struct execution_control_state
*ecs
= &ecss
;
2436 memset (ecs
, 0, sizeof (*ecs
));
2438 old_chain
= make_cleanup_restore_current_thread ();
2440 switch_to_thread (info
->ptid
);
2442 /* Go through handle_inferior_event/normal_stop, so we always
2443 have consistent output as if the stop event had been
2445 ecs
->ptid
= info
->ptid
;
2446 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2447 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2448 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
2450 handle_inferior_event (ecs
);
2452 if (!ecs
->wait_some_more
)
2454 struct thread_info
*tp
;
2458 /* Finish off the continuations. */
2459 tp
= inferior_thread ();
2460 do_all_intermediate_continuations_thread (tp
, 1);
2461 do_all_continuations_thread (tp
, 1);
2464 do_cleanups (old_chain
);
2470 /* This function is attached as a "thread_stop_requested" observer.
2471 Cleanup local state that assumed the PTID was to be resumed, and
2472 report the stop to the frontend. */
2475 infrun_thread_stop_requested (ptid_t ptid
)
2477 struct displaced_step_inferior_state
*displaced
;
2479 /* PTID was requested to stop. Remove it from the displaced
2480 stepping queue, so we don't try to resume it automatically. */
2482 for (displaced
= displaced_step_inferior_states
;
2484 displaced
= displaced
->next
)
2486 struct displaced_step_request
*it
, **prev_next_p
;
2488 it
= displaced
->step_request_queue
;
2489 prev_next_p
= &displaced
->step_request_queue
;
2492 if (ptid_match (it
->ptid
, ptid
))
2494 *prev_next_p
= it
->next
;
2500 prev_next_p
= &it
->next
;
2507 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2511 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2513 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2514 nullify_last_target_wait_ptid ();
2517 /* Callback for iterate_over_threads. */
2520 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
2522 if (is_exited (info
->ptid
))
2525 delete_step_resume_breakpoint (info
);
2526 delete_exception_resume_breakpoint (info
);
2530 /* In all-stop, delete the step resume breakpoint of any thread that
2531 had one. In non-stop, delete the step resume breakpoint of the
2532 thread that just stopped. */
2535 delete_step_thread_step_resume_breakpoint (void)
2537 if (!target_has_execution
2538 || ptid_equal (inferior_ptid
, null_ptid
))
2539 /* If the inferior has exited, we have already deleted the step
2540 resume breakpoints out of GDB's lists. */
2545 /* If in non-stop mode, only delete the step-resume or
2546 longjmp-resume breakpoint of the thread that just stopped
2548 struct thread_info
*tp
= inferior_thread ();
2550 delete_step_resume_breakpoint (tp
);
2551 delete_exception_resume_breakpoint (tp
);
2554 /* In all-stop mode, delete all step-resume and longjmp-resume
2555 breakpoints of any thread that had them. */
2556 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
2559 /* A cleanup wrapper. */
2562 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
2564 delete_step_thread_step_resume_breakpoint ();
2567 /* Pretty print the results of target_wait, for debugging purposes. */
2570 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
2571 const struct target_waitstatus
*ws
)
2573 char *status_string
= target_waitstatus_to_string (ws
);
2574 struct ui_file
*tmp_stream
= mem_fileopen ();
2577 /* The text is split over several lines because it was getting too long.
2578 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2579 output as a unit; we want only one timestamp printed if debug_timestamp
2582 fprintf_unfiltered (tmp_stream
,
2583 "infrun: target_wait (%d", PIDGET (waiton_ptid
));
2584 if (PIDGET (waiton_ptid
) != -1)
2585 fprintf_unfiltered (tmp_stream
,
2586 " [%s]", target_pid_to_str (waiton_ptid
));
2587 fprintf_unfiltered (tmp_stream
, ", status) =\n");
2588 fprintf_unfiltered (tmp_stream
,
2589 "infrun: %d [%s],\n",
2590 PIDGET (result_ptid
), target_pid_to_str (result_ptid
));
2591 fprintf_unfiltered (tmp_stream
,
2595 text
= ui_file_xstrdup (tmp_stream
, NULL
);
2597 /* This uses %s in part to handle %'s in the text, but also to avoid
2598 a gcc error: the format attribute requires a string literal. */
2599 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
2601 xfree (status_string
);
2603 ui_file_delete (tmp_stream
);
2606 /* Prepare and stabilize the inferior for detaching it. E.g.,
2607 detaching while a thread is displaced stepping is a recipe for
2608 crashing it, as nothing would readjust the PC out of the scratch
2612 prepare_for_detach (void)
2614 struct inferior
*inf
= current_inferior ();
2615 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
2616 struct cleanup
*old_chain_1
;
2617 struct displaced_step_inferior_state
*displaced
;
2619 displaced
= get_displaced_stepping_state (inf
->pid
);
2621 /* Is any thread of this process displaced stepping? If not,
2622 there's nothing else to do. */
2623 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
2627 fprintf_unfiltered (gdb_stdlog
,
2628 "displaced-stepping in-process while detaching");
2630 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
2633 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
2635 struct cleanup
*old_chain_2
;
2636 struct execution_control_state ecss
;
2637 struct execution_control_state
*ecs
;
2640 memset (ecs
, 0, sizeof (*ecs
));
2642 overlay_cache_invalid
= 1;
2644 if (deprecated_target_wait_hook
)
2645 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
2647 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
2650 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
2652 /* If an error happens while handling the event, propagate GDB's
2653 knowledge of the executing state to the frontend/user running
2655 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
2658 /* In non-stop mode, each thread is handled individually.
2659 Switch early, so the global state is set correctly for this
2662 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2663 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2664 context_switch (ecs
->ptid
);
2666 /* Now figure out what to do with the result of the result. */
2667 handle_inferior_event (ecs
);
2669 /* No error, don't finish the state yet. */
2670 discard_cleanups (old_chain_2
);
2672 /* Breakpoints and watchpoints are not installed on the target
2673 at this point, and signals are passed directly to the
2674 inferior, so this must mean the process is gone. */
2675 if (!ecs
->wait_some_more
)
2677 discard_cleanups (old_chain_1
);
2678 error (_("Program exited while detaching"));
2682 discard_cleanups (old_chain_1
);
2685 /* Wait for control to return from inferior to debugger.
2687 If inferior gets a signal, we may decide to start it up again
2688 instead of returning. That is why there is a loop in this function.
2689 When this function actually returns it means the inferior
2690 should be left stopped and GDB should read more commands. */
2693 wait_for_inferior (void)
2695 struct cleanup
*old_cleanups
;
2699 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
2702 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
2706 struct execution_control_state ecss
;
2707 struct execution_control_state
*ecs
= &ecss
;
2708 struct cleanup
*old_chain
;
2710 memset (ecs
, 0, sizeof (*ecs
));
2712 overlay_cache_invalid
= 1;
2714 if (deprecated_target_wait_hook
)
2715 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
2717 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
2720 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2722 /* If an error happens while handling the event, propagate GDB's
2723 knowledge of the executing state to the frontend/user running
2725 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2727 /* Now figure out what to do with the result of the result. */
2728 handle_inferior_event (ecs
);
2730 /* No error, don't finish the state yet. */
2731 discard_cleanups (old_chain
);
2733 if (!ecs
->wait_some_more
)
2737 do_cleanups (old_cleanups
);
2740 /* Asynchronous version of wait_for_inferior. It is called by the
2741 event loop whenever a change of state is detected on the file
2742 descriptor corresponding to the target. It can be called more than
2743 once to complete a single execution command. In such cases we need
2744 to keep the state in a global variable ECSS. If it is the last time
2745 that this function is called for a single execution command, then
2746 report to the user that the inferior has stopped, and do the
2747 necessary cleanups. */
2750 fetch_inferior_event (void *client_data
)
2752 struct execution_control_state ecss
;
2753 struct execution_control_state
*ecs
= &ecss
;
2754 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
2755 struct cleanup
*ts_old_chain
;
2756 int was_sync
= sync_execution
;
2759 memset (ecs
, 0, sizeof (*ecs
));
2761 /* We're handling a live event, so make sure we're doing live
2762 debugging. If we're looking at traceframes while the target is
2763 running, we're going to need to get back to that mode after
2764 handling the event. */
2767 make_cleanup_restore_current_traceframe ();
2768 set_current_traceframe (-1);
2772 /* In non-stop mode, the user/frontend should not notice a thread
2773 switch due to internal events. Make sure we reverse to the
2774 user selected thread and frame after handling the event and
2775 running any breakpoint commands. */
2776 make_cleanup_restore_current_thread ();
2778 overlay_cache_invalid
= 1;
2780 make_cleanup_restore_integer (&execution_direction
);
2781 execution_direction
= target_execution_direction ();
2783 if (deprecated_target_wait_hook
)
2785 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2787 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2790 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2793 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
2794 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
2795 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2796 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2797 /* In non-stop mode, each thread is handled individually. Switch
2798 early, so the global state is set correctly for this
2800 context_switch (ecs
->ptid
);
2802 /* If an error happens while handling the event, propagate GDB's
2803 knowledge of the executing state to the frontend/user running
2806 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2808 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
2810 /* Get executed before make_cleanup_restore_current_thread above to apply
2811 still for the thread which has thrown the exception. */
2812 make_bpstat_clear_actions_cleanup ();
2814 /* Now figure out what to do with the result of the result. */
2815 handle_inferior_event (ecs
);
2817 if (!ecs
->wait_some_more
)
2819 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2821 delete_step_thread_step_resume_breakpoint ();
2823 /* We may not find an inferior if this was a process exit. */
2824 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
2827 if (target_has_execution
2828 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
2829 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2830 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2831 && ecs
->event_thread
->step_multi
2832 && ecs
->event_thread
->control
.stop_step
)
2833 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
2836 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2841 /* No error, don't finish the thread states yet. */
2842 discard_cleanups (ts_old_chain
);
2844 /* Revert thread and frame. */
2845 do_cleanups (old_chain
);
2847 /* If the inferior was in sync execution mode, and now isn't,
2848 restore the prompt (a synchronous execution command has finished,
2849 and we're ready for input). */
2850 if (interpreter_async
&& was_sync
&& !sync_execution
)
2851 display_gdb_prompt (0);
2855 && exec_done_display_p
2856 && (ptid_equal (inferior_ptid
, null_ptid
)
2857 || !is_running (inferior_ptid
)))
2858 printf_unfiltered (_("completed.\n"));
2861 /* Record the frame and location we're currently stepping through. */
2863 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
2865 struct thread_info
*tp
= inferior_thread ();
2867 tp
->control
.step_frame_id
= get_frame_id (frame
);
2868 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
2870 tp
->current_symtab
= sal
.symtab
;
2871 tp
->current_line
= sal
.line
;
2874 /* Clear context switchable stepping state. */
2877 init_thread_stepping_state (struct thread_info
*tss
)
2879 tss
->stepping_over_breakpoint
= 0;
2880 tss
->step_after_step_resume_breakpoint
= 0;
2883 /* Return the cached copy of the last pid/waitstatus returned by
2884 target_wait()/deprecated_target_wait_hook(). The data is actually
2885 cached by handle_inferior_event(), which gets called immediately
2886 after target_wait()/deprecated_target_wait_hook(). */
2889 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
2891 *ptidp
= target_last_wait_ptid
;
2892 *status
= target_last_waitstatus
;
2896 nullify_last_target_wait_ptid (void)
2898 target_last_wait_ptid
= minus_one_ptid
;
2901 /* Switch thread contexts. */
2904 context_switch (ptid_t ptid
)
2906 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
2908 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
2909 target_pid_to_str (inferior_ptid
));
2910 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
2911 target_pid_to_str (ptid
));
2914 switch_to_thread (ptid
);
2918 adjust_pc_after_break (struct execution_control_state
*ecs
)
2920 struct regcache
*regcache
;
2921 struct gdbarch
*gdbarch
;
2922 struct address_space
*aspace
;
2923 CORE_ADDR breakpoint_pc
;
2925 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2926 we aren't, just return.
2928 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2929 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2930 implemented by software breakpoints should be handled through the normal
2933 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2934 different signals (SIGILL or SIGEMT for instance), but it is less
2935 clear where the PC is pointing afterwards. It may not match
2936 gdbarch_decr_pc_after_break. I don't know any specific target that
2937 generates these signals at breakpoints (the code has been in GDB since at
2938 least 1992) so I can not guess how to handle them here.
2940 In earlier versions of GDB, a target with
2941 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2942 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2943 target with both of these set in GDB history, and it seems unlikely to be
2944 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2946 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
2949 if (ecs
->ws
.value
.sig
!= GDB_SIGNAL_TRAP
)
2952 /* In reverse execution, when a breakpoint is hit, the instruction
2953 under it has already been de-executed. The reported PC always
2954 points at the breakpoint address, so adjusting it further would
2955 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2958 B1 0x08000000 : INSN1
2959 B2 0x08000001 : INSN2
2961 PC -> 0x08000003 : INSN4
2963 Say you're stopped at 0x08000003 as above. Reverse continuing
2964 from that point should hit B2 as below. Reading the PC when the
2965 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2966 been de-executed already.
2968 B1 0x08000000 : INSN1
2969 B2 PC -> 0x08000001 : INSN2
2973 We can't apply the same logic as for forward execution, because
2974 we would wrongly adjust the PC to 0x08000000, since there's a
2975 breakpoint at PC - 1. We'd then report a hit on B1, although
2976 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2978 if (execution_direction
== EXEC_REVERSE
)
2981 /* If this target does not decrement the PC after breakpoints, then
2982 we have nothing to do. */
2983 regcache
= get_thread_regcache (ecs
->ptid
);
2984 gdbarch
= get_regcache_arch (regcache
);
2985 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
2988 aspace
= get_regcache_aspace (regcache
);
2990 /* Find the location where (if we've hit a breakpoint) the
2991 breakpoint would be. */
2992 breakpoint_pc
= regcache_read_pc (regcache
)
2993 - gdbarch_decr_pc_after_break (gdbarch
);
2995 /* Check whether there actually is a software breakpoint inserted at
2998 If in non-stop mode, a race condition is possible where we've
2999 removed a breakpoint, but stop events for that breakpoint were
3000 already queued and arrive later. To suppress those spurious
3001 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3002 and retire them after a number of stop events are reported. */
3003 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3004 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3006 struct cleanup
*old_cleanups
= NULL
;
3009 old_cleanups
= record_gdb_operation_disable_set ();
3011 /* When using hardware single-step, a SIGTRAP is reported for both
3012 a completed single-step and a software breakpoint. Need to
3013 differentiate between the two, as the latter needs adjusting
3014 but the former does not.
3016 The SIGTRAP can be due to a completed hardware single-step only if
3017 - we didn't insert software single-step breakpoints
3018 - the thread to be examined is still the current thread
3019 - this thread is currently being stepped
3021 If any of these events did not occur, we must have stopped due
3022 to hitting a software breakpoint, and have to back up to the
3025 As a special case, we could have hardware single-stepped a
3026 software breakpoint. In this case (prev_pc == breakpoint_pc),
3027 we also need to back up to the breakpoint address. */
3029 if (singlestep_breakpoints_inserted_p
3030 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
3031 || !currently_stepping (ecs
->event_thread
)
3032 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
3033 regcache_write_pc (regcache
, breakpoint_pc
);
3036 do_cleanups (old_cleanups
);
3041 init_infwait_state (void)
3043 waiton_ptid
= pid_to_ptid (-1);
3044 infwait_state
= infwait_normal_state
;
3048 error_is_running (void)
3050 error (_("Cannot execute this command while "
3051 "the selected thread is running."));
3055 ensure_not_running (void)
3057 if (is_running (inferior_ptid
))
3058 error_is_running ();
3062 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3064 for (frame
= get_prev_frame (frame
);
3066 frame
= get_prev_frame (frame
))
3068 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3070 if (get_frame_type (frame
) != INLINE_FRAME
)
3077 /* Auxiliary function that handles syscall entry/return events.
3078 It returns 1 if the inferior should keep going (and GDB
3079 should ignore the event), or 0 if the event deserves to be
3083 handle_syscall_event (struct execution_control_state
*ecs
)
3085 struct regcache
*regcache
;
3086 struct gdbarch
*gdbarch
;
3089 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3090 context_switch (ecs
->ptid
);
3092 regcache
= get_thread_regcache (ecs
->ptid
);
3093 gdbarch
= get_regcache_arch (regcache
);
3094 syscall_number
= ecs
->ws
.value
.syscall_number
;
3095 stop_pc
= regcache_read_pc (regcache
);
3097 if (catch_syscall_enabled () > 0
3098 && catching_syscall_number (syscall_number
) > 0)
3101 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3104 ecs
->event_thread
->control
.stop_bpstat
3105 = bpstat_stop_status (get_regcache_aspace (regcache
),
3106 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3108 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3110 if (!ecs
->random_signal
)
3112 /* Catchpoint hit. */
3113 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3118 /* If no catchpoint triggered for this, then keep going. */
3119 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3124 /* Clear the supplied execution_control_state's stop_func_* fields. */
3127 clear_stop_func (struct execution_control_state
*ecs
)
3129 ecs
->stop_func_filled_in
= 0;
3130 ecs
->stop_func_start
= 0;
3131 ecs
->stop_func_end
= 0;
3132 ecs
->stop_func_name
= NULL
;
3135 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3138 fill_in_stop_func (struct gdbarch
*gdbarch
,
3139 struct execution_control_state
*ecs
)
3141 if (!ecs
->stop_func_filled_in
)
3143 /* Don't care about return value; stop_func_start and stop_func_name
3144 will both be 0 if it doesn't work. */
3145 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3146 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3147 ecs
->stop_func_start
3148 += gdbarch_deprecated_function_start_offset (gdbarch
);
3150 ecs
->stop_func_filled_in
= 1;
3154 /* Given an execution control state that has been freshly filled in
3155 by an event from the inferior, figure out what it means and take
3156 appropriate action. */
3159 handle_inferior_event (struct execution_control_state
*ecs
)
3161 struct frame_info
*frame
;
3162 struct gdbarch
*gdbarch
;
3163 int stopped_by_watchpoint
;
3164 int stepped_after_stopped_by_watchpoint
= 0;
3165 struct symtab_and_line stop_pc_sal
;
3166 enum stop_kind stop_soon
;
3168 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3170 /* We had an event in the inferior, but we are not interested in
3171 handling it at this level. The lower layers have already
3172 done what needs to be done, if anything.
3174 One of the possible circumstances for this is when the
3175 inferior produces output for the console. The inferior has
3176 not stopped, and we are ignoring the event. Another possible
3177 circumstance is any event which the lower level knows will be
3178 reported multiple times without an intervening resume. */
3180 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3181 prepare_to_wait (ecs
);
3185 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3186 && target_can_async_p () && !sync_execution
)
3188 /* There were no unwaited-for children left in the target, but,
3189 we're not synchronously waiting for events either. Just
3190 ignore. Otherwise, if we were running a synchronous
3191 execution command, we need to cancel it and give the user
3192 back the terminal. */
3194 fprintf_unfiltered (gdb_stdlog
,
3195 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3196 prepare_to_wait (ecs
);
3200 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3201 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3202 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
3204 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3207 stop_soon
= inf
->control
.stop_soon
;
3210 stop_soon
= NO_STOP_QUIETLY
;
3212 /* Cache the last pid/waitstatus. */
3213 target_last_wait_ptid
= ecs
->ptid
;
3214 target_last_waitstatus
= ecs
->ws
;
3216 /* Always clear state belonging to the previous time we stopped. */
3217 stop_stack_dummy
= STOP_NONE
;
3219 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3221 /* No unwaited-for children left. IOW, all resumed children
3224 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3226 stop_print_frame
= 0;
3227 stop_stepping (ecs
);
3231 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3232 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3233 && !ptid_equal (ecs
->ptid
, minus_one_ptid
))
3235 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3236 /* If it's a new thread, add it to the thread database. */
3237 if (ecs
->event_thread
== NULL
)
3238 ecs
->event_thread
= add_thread (ecs
->ptid
);
3241 /* Dependent on valid ECS->EVENT_THREAD. */
3242 adjust_pc_after_break (ecs
);
3244 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3245 reinit_frame_cache ();
3247 breakpoint_retire_moribund ();
3249 /* First, distinguish signals caused by the debugger from signals
3250 that have to do with the program's own actions. Note that
3251 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3252 on the operating system version. Here we detect when a SIGILL or
3253 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3254 something similar for SIGSEGV, since a SIGSEGV will be generated
3255 when we're trying to execute a breakpoint instruction on a
3256 non-executable stack. This happens for call dummy breakpoints
3257 for architectures like SPARC that place call dummies on the
3259 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3260 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3261 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3262 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3264 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3266 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3267 regcache_read_pc (regcache
)))
3270 fprintf_unfiltered (gdb_stdlog
,
3271 "infrun: Treating signal as SIGTRAP\n");
3272 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3276 /* Mark the non-executing threads accordingly. In all-stop, all
3277 threads of all processes are stopped when we get any event
3278 reported. In non-stop mode, only the event thread stops. If
3279 we're handling a process exit in non-stop mode, there's nothing
3280 to do, as threads of the dead process are gone, and threads of
3281 any other process were left running. */
3283 set_executing (minus_one_ptid
, 0);
3284 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3285 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3286 set_executing (ecs
->ptid
, 0);
3288 switch (infwait_state
)
3290 case infwait_thread_hop_state
:
3292 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
3295 case infwait_normal_state
:
3297 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
3300 case infwait_step_watch_state
:
3302 fprintf_unfiltered (gdb_stdlog
,
3303 "infrun: infwait_step_watch_state\n");
3305 stepped_after_stopped_by_watchpoint
= 1;
3308 case infwait_nonstep_watch_state
:
3310 fprintf_unfiltered (gdb_stdlog
,
3311 "infrun: infwait_nonstep_watch_state\n");
3312 insert_breakpoints ();
3314 /* FIXME-maybe: is this cleaner than setting a flag? Does it
3315 handle things like signals arriving and other things happening
3316 in combination correctly? */
3317 stepped_after_stopped_by_watchpoint
= 1;
3321 internal_error (__FILE__
, __LINE__
, _("bad switch"));
3324 infwait_state
= infwait_normal_state
;
3325 waiton_ptid
= pid_to_ptid (-1);
3327 switch (ecs
->ws
.kind
)
3329 case TARGET_WAITKIND_LOADED
:
3331 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3332 /* Ignore gracefully during startup of the inferior, as it might
3333 be the shell which has just loaded some objects, otherwise
3334 add the symbols for the newly loaded objects. Also ignore at
3335 the beginning of an attach or remote session; we will query
3336 the full list of libraries once the connection is
3338 if (stop_soon
== NO_STOP_QUIETLY
)
3340 struct regcache
*regcache
;
3342 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3343 context_switch (ecs
->ptid
);
3344 regcache
= get_thread_regcache (ecs
->ptid
);
3346 handle_solib_event ();
3348 ecs
->event_thread
->control
.stop_bpstat
3349 = bpstat_stop_status (get_regcache_aspace (regcache
),
3350 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3352 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3354 if (!ecs
->random_signal
)
3356 /* A catchpoint triggered. */
3357 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3358 goto process_event_stop_test
;
3361 /* If requested, stop when the dynamic linker notifies
3362 gdb of events. This allows the user to get control
3363 and place breakpoints in initializer routines for
3364 dynamically loaded objects (among other things). */
3365 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3366 if (stop_on_solib_events
)
3368 /* Make sure we print "Stopped due to solib-event" in
3370 stop_print_frame
= 1;
3372 stop_stepping (ecs
);
3377 /* If we are skipping through a shell, or through shared library
3378 loading that we aren't interested in, resume the program. If
3379 we're running the program normally, also resume. But stop if
3380 we're attaching or setting up a remote connection. */
3381 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3383 /* Loading of shared libraries might have changed breakpoint
3384 addresses. Make sure new breakpoints are inserted. */
3385 if (stop_soon
== NO_STOP_QUIETLY
3386 && !breakpoints_always_inserted_mode ())
3387 insert_breakpoints ();
3388 resume (0, GDB_SIGNAL_0
);
3389 prepare_to_wait (ecs
);
3395 case TARGET_WAITKIND_SPURIOUS
:
3397 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3398 resume (0, GDB_SIGNAL_0
);
3399 prepare_to_wait (ecs
);
3402 case TARGET_WAITKIND_EXITED
:
3404 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
3405 inferior_ptid
= ecs
->ptid
;
3406 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3407 set_current_program_space (current_inferior ()->pspace
);
3408 handle_vfork_child_exec_or_exit (0);
3409 target_terminal_ours (); /* Must do this before mourn anyway. */
3410 print_exited_reason (ecs
->ws
.value
.integer
);
3412 /* Record the exit code in the convenience variable $_exitcode, so
3413 that the user can inspect this again later. */
3414 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3415 (LONGEST
) ecs
->ws
.value
.integer
);
3417 /* Also record this in the inferior itself. */
3418 current_inferior ()->has_exit_code
= 1;
3419 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3421 gdb_flush (gdb_stdout
);
3422 target_mourn_inferior ();
3423 singlestep_breakpoints_inserted_p
= 0;
3424 cancel_single_step_breakpoints ();
3425 stop_print_frame
= 0;
3426 stop_stepping (ecs
);
3429 case TARGET_WAITKIND_SIGNALLED
:
3431 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
3432 inferior_ptid
= ecs
->ptid
;
3433 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3434 set_current_program_space (current_inferior ()->pspace
);
3435 handle_vfork_child_exec_or_exit (0);
3436 stop_print_frame
= 0;
3437 target_terminal_ours (); /* Must do this before mourn anyway. */
3439 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
3440 reach here unless the inferior is dead. However, for years
3441 target_kill() was called here, which hints that fatal signals aren't
3442 really fatal on some systems. If that's true, then some changes
3444 target_mourn_inferior ();
3446 print_signal_exited_reason (ecs
->ws
.value
.sig
);
3447 singlestep_breakpoints_inserted_p
= 0;
3448 cancel_single_step_breakpoints ();
3449 stop_stepping (ecs
);
3452 /* The following are the only cases in which we keep going;
3453 the above cases end in a continue or goto. */
3454 case TARGET_WAITKIND_FORKED
:
3455 case TARGET_WAITKIND_VFORKED
:
3457 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3459 /* Check whether the inferior is displaced stepping. */
3461 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3462 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3463 struct displaced_step_inferior_state
*displaced
3464 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3466 /* If checking displaced stepping is supported, and thread
3467 ecs->ptid is displaced stepping. */
3468 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3470 struct inferior
*parent_inf
3471 = find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3472 struct regcache
*child_regcache
;
3473 CORE_ADDR parent_pc
;
3475 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3476 indicating that the displaced stepping of syscall instruction
3477 has been done. Perform cleanup for parent process here. Note
3478 that this operation also cleans up the child process for vfork,
3479 because their pages are shared. */
3480 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
3482 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3484 /* Restore scratch pad for child process. */
3485 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3488 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3489 the child's PC is also within the scratchpad. Set the child's PC
3490 to the parent's PC value, which has already been fixed up.
3491 FIXME: we use the parent's aspace here, although we're touching
3492 the child, because the child hasn't been added to the inferior
3493 list yet at this point. */
3496 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3498 parent_inf
->aspace
);
3499 /* Read PC value of parent process. */
3500 parent_pc
= regcache_read_pc (regcache
);
3502 if (debug_displaced
)
3503 fprintf_unfiltered (gdb_stdlog
,
3504 "displaced: write child pc from %s to %s\n",
3506 regcache_read_pc (child_regcache
)),
3507 paddress (gdbarch
, parent_pc
));
3509 regcache_write_pc (child_regcache
, parent_pc
);
3513 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3515 context_switch (ecs
->ptid
);
3516 reinit_frame_cache ();
3519 /* Immediately detach breakpoints from the child before there's
3520 any chance of letting the user delete breakpoints from the
3521 breakpoint lists. If we don't do this early, it's easy to
3522 leave left over traps in the child, vis: "break foo; catch
3523 fork; c; <fork>; del; c; <child calls foo>". We only follow
3524 the fork on the last `continue', and by that time the
3525 breakpoint at "foo" is long gone from the breakpoint table.
3526 If we vforked, then we don't need to unpatch here, since both
3527 parent and child are sharing the same memory pages; we'll
3528 need to unpatch at follow/detach time instead to be certain
3529 that new breakpoints added between catchpoint hit time and
3530 vfork follow are detached. */
3531 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3533 int child_pid
= ptid_get_pid (ecs
->ws
.value
.related_pid
);
3535 /* This won't actually modify the breakpoint list, but will
3536 physically remove the breakpoints from the child. */
3537 detach_breakpoints (child_pid
);
3540 if (singlestep_breakpoints_inserted_p
)
3542 /* Pull the single step breakpoints out of the target. */
3543 remove_single_step_breakpoints ();
3544 singlestep_breakpoints_inserted_p
= 0;
3547 /* In case the event is caught by a catchpoint, remember that
3548 the event is to be followed at the next resume of the thread,
3549 and not immediately. */
3550 ecs
->event_thread
->pending_follow
= ecs
->ws
;
3552 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3554 ecs
->event_thread
->control
.stop_bpstat
3555 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3556 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3558 /* Note that we're interested in knowing the bpstat actually
3559 causes a stop, not just if it may explain the signal.
3560 Software watchpoints, for example, always appear in the
3563 = !bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
);
3565 /* If no catchpoint triggered for this, then keep going. */
3566 if (ecs
->random_signal
)
3572 = (follow_fork_mode_string
== follow_fork_mode_child
);
3574 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3576 should_resume
= follow_fork ();
3579 child
= ecs
->ws
.value
.related_pid
;
3581 /* In non-stop mode, also resume the other branch. */
3582 if (non_stop
&& !detach_fork
)
3585 switch_to_thread (parent
);
3587 switch_to_thread (child
);
3589 ecs
->event_thread
= inferior_thread ();
3590 ecs
->ptid
= inferior_ptid
;
3595 switch_to_thread (child
);
3597 switch_to_thread (parent
);
3599 ecs
->event_thread
= inferior_thread ();
3600 ecs
->ptid
= inferior_ptid
;
3605 stop_stepping (ecs
);
3608 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3609 goto process_event_stop_test
;
3611 case TARGET_WAITKIND_VFORK_DONE
:
3612 /* Done with the shared memory region. Re-insert breakpoints in
3613 the parent, and keep going. */
3616 fprintf_unfiltered (gdb_stdlog
,
3617 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3619 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3620 context_switch (ecs
->ptid
);
3622 current_inferior ()->waiting_for_vfork_done
= 0;
3623 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
3624 /* This also takes care of reinserting breakpoints in the
3625 previously locked inferior. */
3629 case TARGET_WAITKIND_EXECD
:
3631 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
3633 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3635 context_switch (ecs
->ptid
);
3636 reinit_frame_cache ();
3639 singlestep_breakpoints_inserted_p
= 0;
3640 cancel_single_step_breakpoints ();
3642 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3644 /* Do whatever is necessary to the parent branch of the vfork. */
3645 handle_vfork_child_exec_or_exit (1);
3647 /* This causes the eventpoints and symbol table to be reset.
3648 Must do this now, before trying to determine whether to
3650 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
3652 ecs
->event_thread
->control
.stop_bpstat
3653 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3654 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3656 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3658 /* Note that this may be referenced from inside
3659 bpstat_stop_status above, through inferior_has_execd. */
3660 xfree (ecs
->ws
.value
.execd_pathname
);
3661 ecs
->ws
.value
.execd_pathname
= NULL
;
3663 /* If no catchpoint triggered for this, then keep going. */
3664 if (ecs
->random_signal
)
3666 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3670 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3671 goto process_event_stop_test
;
3673 /* Be careful not to try to gather much state about a thread
3674 that's in a syscall. It's frequently a losing proposition. */
3675 case TARGET_WAITKIND_SYSCALL_ENTRY
:
3677 fprintf_unfiltered (gdb_stdlog
,
3678 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3679 /* Getting the current syscall number. */
3680 if (handle_syscall_event (ecs
) != 0)
3682 goto process_event_stop_test
;
3684 /* Before examining the threads further, step this thread to
3685 get it entirely out of the syscall. (We get notice of the
3686 event when the thread is just on the verge of exiting a
3687 syscall. Stepping one instruction seems to get it back
3689 case TARGET_WAITKIND_SYSCALL_RETURN
:
3691 fprintf_unfiltered (gdb_stdlog
,
3692 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3693 if (handle_syscall_event (ecs
) != 0)
3695 goto process_event_stop_test
;
3697 case TARGET_WAITKIND_STOPPED
:
3699 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
3700 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
3703 case TARGET_WAITKIND_NO_HISTORY
:
3705 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
3706 /* Reverse execution: target ran out of history info. */
3707 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3708 print_no_history_reason ();
3709 stop_stepping (ecs
);
3713 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
3715 /* Do we need to clean up the state of a thread that has
3716 completed a displaced single-step? (Doing so usually affects
3717 the PC, so do it here, before we set stop_pc.) */
3718 displaced_step_fixup (ecs
->ptid
,
3719 ecs
->event_thread
->suspend
.stop_signal
);
3721 /* If we either finished a single-step or hit a breakpoint, but
3722 the user wanted this thread to be stopped, pretend we got a
3723 SIG0 (generic unsignaled stop). */
3725 if (ecs
->event_thread
->stop_requested
3726 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3727 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3730 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3734 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3735 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3736 struct cleanup
*old_chain
= save_inferior_ptid ();
3738 inferior_ptid
= ecs
->ptid
;
3740 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
3741 paddress (gdbarch
, stop_pc
));
3742 if (target_stopped_by_watchpoint ())
3746 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
3748 if (target_stopped_data_address (¤t_target
, &addr
))
3749 fprintf_unfiltered (gdb_stdlog
,
3750 "infrun: stopped data address = %s\n",
3751 paddress (gdbarch
, addr
));
3753 fprintf_unfiltered (gdb_stdlog
,
3754 "infrun: (no data address available)\n");
3757 do_cleanups (old_chain
);
3760 if (stepping_past_singlestep_breakpoint
)
3762 gdb_assert (singlestep_breakpoints_inserted_p
);
3763 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
3764 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
3766 stepping_past_singlestep_breakpoint
= 0;
3768 /* We've either finished single-stepping past the single-step
3769 breakpoint, or stopped for some other reason. It would be nice if
3770 we could tell, but we can't reliably. */
3771 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3774 fprintf_unfiltered (gdb_stdlog
,
3775 "infrun: stepping_past_"
3776 "singlestep_breakpoint\n");
3777 /* Pull the single step breakpoints out of the target. */
3778 remove_single_step_breakpoints ();
3779 singlestep_breakpoints_inserted_p
= 0;
3781 ecs
->random_signal
= 0;
3782 ecs
->event_thread
->control
.trap_expected
= 0;
3784 context_switch (saved_singlestep_ptid
);
3785 if (deprecated_context_hook
)
3786 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3788 resume (1, GDB_SIGNAL_0
);
3789 prepare_to_wait (ecs
);
3794 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
3796 /* In non-stop mode, there's never a deferred_step_ptid set. */
3797 gdb_assert (!non_stop
);
3799 /* If we stopped for some other reason than single-stepping, ignore
3800 the fact that we were supposed to switch back. */
3801 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3804 fprintf_unfiltered (gdb_stdlog
,
3805 "infrun: handling deferred step\n");
3807 /* Pull the single step breakpoints out of the target. */
3808 if (singlestep_breakpoints_inserted_p
)
3810 remove_single_step_breakpoints ();
3811 singlestep_breakpoints_inserted_p
= 0;
3814 ecs
->event_thread
->control
.trap_expected
= 0;
3816 context_switch (deferred_step_ptid
);
3817 deferred_step_ptid
= null_ptid
;
3818 /* Suppress spurious "Switching to ..." message. */
3819 previous_inferior_ptid
= inferior_ptid
;
3821 resume (1, GDB_SIGNAL_0
);
3822 prepare_to_wait (ecs
);
3826 deferred_step_ptid
= null_ptid
;
3829 /* See if a thread hit a thread-specific breakpoint that was meant for
3830 another thread. If so, then step that thread past the breakpoint,
3833 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3835 int thread_hop_needed
= 0;
3836 struct address_space
*aspace
=
3837 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
3839 /* Check if a regular breakpoint has been hit before checking
3840 for a potential single step breakpoint. Otherwise, GDB will
3841 not see this breakpoint hit when stepping onto breakpoints. */
3842 if (regular_breakpoint_inserted_here_p (aspace
, stop_pc
))
3844 ecs
->random_signal
= 0;
3845 if (!breakpoint_thread_match (aspace
, stop_pc
, ecs
->ptid
))
3846 thread_hop_needed
= 1;
3848 else if (singlestep_breakpoints_inserted_p
)
3850 /* We have not context switched yet, so this should be true
3851 no matter which thread hit the singlestep breakpoint. */
3852 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
3854 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
3856 target_pid_to_str (ecs
->ptid
));
3858 ecs
->random_signal
= 0;
3859 /* The call to in_thread_list is necessary because PTIDs sometimes
3860 change when we go from single-threaded to multi-threaded. If
3861 the singlestep_ptid is still in the list, assume that it is
3862 really different from ecs->ptid. */
3863 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
3864 && in_thread_list (singlestep_ptid
))
3866 /* If the PC of the thread we were trying to single-step
3867 has changed, discard this event (which we were going
3868 to ignore anyway), and pretend we saw that thread
3869 trap. This prevents us continuously moving the
3870 single-step breakpoint forward, one instruction at a
3871 time. If the PC has changed, then the thread we were
3872 trying to single-step has trapped or been signalled,
3873 but the event has not been reported to GDB yet.
3875 There might be some cases where this loses signal
3876 information, if a signal has arrived at exactly the
3877 same time that the PC changed, but this is the best
3878 we can do with the information available. Perhaps we
3879 should arrange to report all events for all threads
3880 when they stop, or to re-poll the remote looking for
3881 this particular thread (i.e. temporarily enable
3884 CORE_ADDR new_singlestep_pc
3885 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
3887 if (new_singlestep_pc
!= singlestep_pc
)
3889 enum gdb_signal stop_signal
;
3892 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
3893 " but expected thread advanced also\n");
3895 /* The current context still belongs to
3896 singlestep_ptid. Don't swap here, since that's
3897 the context we want to use. Just fudge our
3898 state and continue. */
3899 stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
3900 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3901 ecs
->ptid
= singlestep_ptid
;
3902 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3903 ecs
->event_thread
->suspend
.stop_signal
= stop_signal
;
3904 stop_pc
= new_singlestep_pc
;
3909 fprintf_unfiltered (gdb_stdlog
,
3910 "infrun: unexpected thread\n");
3912 thread_hop_needed
= 1;
3913 stepping_past_singlestep_breakpoint
= 1;
3914 saved_singlestep_ptid
= singlestep_ptid
;
3919 if (thread_hop_needed
)
3921 struct regcache
*thread_regcache
;
3922 int remove_status
= 0;
3925 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
3927 /* Switch context before touching inferior memory, the
3928 previous thread may have exited. */
3929 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
3930 context_switch (ecs
->ptid
);
3932 /* Saw a breakpoint, but it was hit by the wrong thread.
3935 if (singlestep_breakpoints_inserted_p
)
3937 /* Pull the single step breakpoints out of the target. */
3938 remove_single_step_breakpoints ();
3939 singlestep_breakpoints_inserted_p
= 0;
3942 /* If the arch can displace step, don't remove the
3944 thread_regcache
= get_thread_regcache (ecs
->ptid
);
3945 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
3946 remove_status
= remove_breakpoints ();
3948 /* Did we fail to remove breakpoints? If so, try
3949 to set the PC past the bp. (There's at least
3950 one situation in which we can fail to remove
3951 the bp's: On HP-UX's that use ttrace, we can't
3952 change the address space of a vforking child
3953 process until the child exits (well, okay, not
3954 then either :-) or execs. */
3955 if (remove_status
!= 0)
3956 error (_("Cannot step over breakpoint hit in wrong thread"));
3961 /* Only need to require the next event from this
3962 thread in all-stop mode. */
3963 waiton_ptid
= ecs
->ptid
;
3964 infwait_state
= infwait_thread_hop_state
;
3967 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3972 else if (singlestep_breakpoints_inserted_p
)
3974 ecs
->random_signal
= 0;
3978 ecs
->random_signal
= 1;
3980 /* See if something interesting happened to the non-current thread. If
3981 so, then switch to that thread. */
3982 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3985 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
3987 context_switch (ecs
->ptid
);
3989 if (deprecated_context_hook
)
3990 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3993 /* At this point, get hold of the now-current thread's frame. */
3994 frame
= get_current_frame ();
3995 gdbarch
= get_frame_arch (frame
);
3997 if (singlestep_breakpoints_inserted_p
)
3999 /* Pull the single step breakpoints out of the target. */
4000 remove_single_step_breakpoints ();
4001 singlestep_breakpoints_inserted_p
= 0;
4004 if (stepped_after_stopped_by_watchpoint
)
4005 stopped_by_watchpoint
= 0;
4007 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
4009 /* If necessary, step over this watchpoint. We'll be back to display
4011 if (stopped_by_watchpoint
4012 && (target_have_steppable_watchpoint
4013 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
4015 /* At this point, we are stopped at an instruction which has
4016 attempted to write to a piece of memory under control of
4017 a watchpoint. The instruction hasn't actually executed
4018 yet. If we were to evaluate the watchpoint expression
4019 now, we would get the old value, and therefore no change
4020 would seem to have occurred.
4022 In order to make watchpoints work `right', we really need
4023 to complete the memory write, and then evaluate the
4024 watchpoint expression. We do this by single-stepping the
4027 It may not be necessary to disable the watchpoint to stop over
4028 it. For example, the PA can (with some kernel cooperation)
4029 single step over a watchpoint without disabling the watchpoint.
4031 It is far more common to need to disable a watchpoint to step
4032 the inferior over it. If we have non-steppable watchpoints,
4033 we must disable the current watchpoint; it's simplest to
4034 disable all watchpoints and breakpoints. */
4037 if (!target_have_steppable_watchpoint
)
4039 remove_breakpoints ();
4040 /* See comment in resume why we need to stop bypassing signals
4041 while breakpoints have been removed. */
4042 target_pass_signals (0, NULL
);
4045 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
4046 target_resume (ecs
->ptid
, hw_step
, GDB_SIGNAL_0
);
4047 waiton_ptid
= ecs
->ptid
;
4048 if (target_have_steppable_watchpoint
)
4049 infwait_state
= infwait_step_watch_state
;
4051 infwait_state
= infwait_nonstep_watch_state
;
4052 prepare_to_wait (ecs
);
4056 clear_stop_func (ecs
);
4057 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4058 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4059 ecs
->event_thread
->control
.stop_step
= 0;
4060 stop_print_frame
= 1;
4061 ecs
->random_signal
= 0;
4062 stopped_by_random_signal
= 0;
4064 /* Hide inlined functions starting here, unless we just performed stepi or
4065 nexti. After stepi and nexti, always show the innermost frame (not any
4066 inline function call sites). */
4067 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4069 struct address_space
*aspace
=
4070 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4072 /* skip_inline_frames is expensive, so we avoid it if we can
4073 determine that the address is one where functions cannot have
4074 been inlined. This improves performance with inferiors that
4075 load a lot of shared libraries, because the solib event
4076 breakpoint is defined as the address of a function (i.e. not
4077 inline). Note that we have to check the previous PC as well
4078 as the current one to catch cases when we have just
4079 single-stepped off a breakpoint prior to reinstating it.
4080 Note that we're assuming that the code we single-step to is
4081 not inline, but that's not definitive: there's nothing
4082 preventing the event breakpoint function from containing
4083 inlined code, and the single-step ending up there. If the
4084 user had set a breakpoint on that inlined code, the missing
4085 skip_inline_frames call would break things. Fortunately
4086 that's an extremely unlikely scenario. */
4087 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4088 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4089 && ecs
->event_thread
->control
.trap_expected
4090 && pc_at_non_inline_function (aspace
,
4091 ecs
->event_thread
->prev_pc
,
4093 skip_inline_frames (ecs
->ptid
);
4096 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4097 && ecs
->event_thread
->control
.trap_expected
4098 && gdbarch_single_step_through_delay_p (gdbarch
)
4099 && currently_stepping (ecs
->event_thread
))
4101 /* We're trying to step off a breakpoint. Turns out that we're
4102 also on an instruction that needs to be stepped multiple
4103 times before it's been fully executing. E.g., architectures
4104 with a delay slot. It needs to be stepped twice, once for
4105 the instruction and once for the delay slot. */
4106 int step_through_delay
4107 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4109 if (debug_infrun
&& step_through_delay
)
4110 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4111 if (ecs
->event_thread
->control
.step_range_end
== 0
4112 && step_through_delay
)
4114 /* The user issued a continue when stopped at a breakpoint.
4115 Set up for another trap and get out of here. */
4116 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4120 else if (step_through_delay
)
4122 /* The user issued a step when stopped at a breakpoint.
4123 Maybe we should stop, maybe we should not - the delay
4124 slot *might* correspond to a line of source. In any
4125 case, don't decide that here, just set
4126 ecs->stepping_over_breakpoint, making sure we
4127 single-step again before breakpoints are re-inserted. */
4128 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4132 /* Look at the cause of the stop, and decide what to do.
4133 The alternatives are:
4134 1) stop_stepping and return; to really stop and return to the debugger,
4135 2) keep_going and return to start up again
4136 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
4137 3) set ecs->random_signal to 1, and the decision between 1 and 2
4138 will be made according to the signal handling tables. */
4140 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4141 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4142 || stop_soon
== STOP_QUIETLY_REMOTE
)
4144 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4148 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4149 stop_print_frame
= 0;
4150 stop_stepping (ecs
);
4154 /* This is originated from start_remote(), start_inferior() and
4155 shared libraries hook functions. */
4156 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4159 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4160 stop_stepping (ecs
);
4164 /* This originates from attach_command(). We need to overwrite
4165 the stop_signal here, because some kernels don't ignore a
4166 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4167 See more comments in inferior.h. On the other hand, if we
4168 get a non-SIGSTOP, report it to the user - assume the backend
4169 will handle the SIGSTOP if it should show up later.
4171 Also consider that the attach is complete when we see a
4172 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4173 target extended-remote report it instead of a SIGSTOP
4174 (e.g. gdbserver). We already rely on SIGTRAP being our
4175 signal, so this is no exception.
4177 Also consider that the attach is complete when we see a
4178 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4179 the target to stop all threads of the inferior, in case the
4180 low level attach operation doesn't stop them implicitly. If
4181 they weren't stopped implicitly, then the stub will report a
4182 GDB_SIGNAL_0, meaning: stopped for no particular reason
4183 other than GDB's request. */
4184 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4185 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
4186 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4187 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
4189 stop_stepping (ecs
);
4190 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4194 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4195 handles this event. */
4196 ecs
->event_thread
->control
.stop_bpstat
4197 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4198 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4200 /* Following in case break condition called a
4202 stop_print_frame
= 1;
4204 /* This is where we handle "moribund" watchpoints. Unlike
4205 software breakpoints traps, hardware watchpoint traps are
4206 always distinguishable from random traps. If no high-level
4207 watchpoint is associated with the reported stop data address
4208 anymore, then the bpstat does not explain the signal ---
4209 simply make sure to ignore it if `stopped_by_watchpoint' is
4213 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4214 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4215 && stopped_by_watchpoint
)
4216 fprintf_unfiltered (gdb_stdlog
,
4217 "infrun: no user watchpoint explains "
4218 "watchpoint SIGTRAP, ignoring\n");
4220 /* NOTE: cagney/2003-03-29: These two checks for a random signal
4221 at one stage in the past included checks for an inferior
4222 function call's call dummy's return breakpoint. The original
4223 comment, that went with the test, read:
4225 ``End of a stack dummy. Some systems (e.g. Sony news) give
4226 another signal besides SIGTRAP, so check here as well as
4229 If someone ever tries to get call dummys on a
4230 non-executable stack to work (where the target would stop
4231 with something like a SIGSEGV), then those tests might need
4232 to be re-instated. Given, however, that the tests were only
4233 enabled when momentary breakpoints were not being used, I
4234 suspect that it won't be the case.
4236 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4237 be necessary for call dummies on a non-executable stack on
4240 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4242 = !(bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4243 || stopped_by_watchpoint
4244 || ecs
->event_thread
->control
.trap_expected
4245 || (ecs
->event_thread
->control
.step_range_end
4246 && (ecs
->event_thread
->control
.step_resume_breakpoint
4250 ecs
->random_signal
= !bpstat_explains_signal
4251 (ecs
->event_thread
->control
.stop_bpstat
);
4252 if (!ecs
->random_signal
)
4253 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
4257 /* When we reach this point, we've pretty much decided
4258 that the reason for stopping must've been a random
4259 (unexpected) signal. */
4262 ecs
->random_signal
= 1;
4264 process_event_stop_test
:
4266 /* Re-fetch current thread's frame in case we did a
4267 "goto process_event_stop_test" above. */
4268 frame
= get_current_frame ();
4269 gdbarch
= get_frame_arch (frame
);
4271 /* For the program's own signals, act according to
4272 the signal handling tables. */
4274 if (ecs
->random_signal
)
4276 /* Signal not for debugging purposes. */
4278 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
4281 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
4282 ecs
->event_thread
->suspend
.stop_signal
);
4284 stopped_by_random_signal
= 1;
4286 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4289 target_terminal_ours_for_output ();
4290 print_signal_received_reason
4291 (ecs
->event_thread
->suspend
.stop_signal
);
4293 /* Always stop on signals if we're either just gaining control
4294 of the program, or the user explicitly requested this thread
4295 to remain stopped. */
4296 if (stop_soon
!= NO_STOP_QUIETLY
4297 || ecs
->event_thread
->stop_requested
4299 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4301 stop_stepping (ecs
);
4304 /* If not going to stop, give terminal back
4305 if we took it away. */
4307 target_terminal_inferior ();
4309 /* Clear the signal if it should not be passed. */
4310 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4311 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4313 if (ecs
->event_thread
->prev_pc
== stop_pc
4314 && ecs
->event_thread
->control
.trap_expected
4315 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4317 /* We were just starting a new sequence, attempting to
4318 single-step off of a breakpoint and expecting a SIGTRAP.
4319 Instead this signal arrives. This signal will take us out
4320 of the stepping range so GDB needs to remember to, when
4321 the signal handler returns, resume stepping off that
4323 /* To simplify things, "continue" is forced to use the same
4324 code paths as single-step - set a breakpoint at the
4325 signal return address and then, once hit, step off that
4328 fprintf_unfiltered (gdb_stdlog
,
4329 "infrun: signal arrived while stepping over "
4332 insert_hp_step_resume_breakpoint_at_frame (frame
);
4333 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4334 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4335 ecs
->event_thread
->control
.trap_expected
= 0;
4340 if (ecs
->event_thread
->control
.step_range_end
!= 0
4341 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4342 && (ecs
->event_thread
->control
.step_range_start
<= stop_pc
4343 && stop_pc
< ecs
->event_thread
->control
.step_range_end
)
4344 && frame_id_eq (get_stack_frame_id (frame
),
4345 ecs
->event_thread
->control
.step_stack_frame_id
)
4346 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4348 /* The inferior is about to take a signal that will take it
4349 out of the single step range. Set a breakpoint at the
4350 current PC (which is presumably where the signal handler
4351 will eventually return) and then allow the inferior to
4354 Note that this is only needed for a signal delivered
4355 while in the single-step range. Nested signals aren't a
4356 problem as they eventually all return. */
4358 fprintf_unfiltered (gdb_stdlog
,
4359 "infrun: signal may take us out of "
4360 "single-step range\n");
4362 insert_hp_step_resume_breakpoint_at_frame (frame
);
4363 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4364 ecs
->event_thread
->control
.trap_expected
= 0;
4369 /* Note: step_resume_breakpoint may be non-NULL. This occures
4370 when either there's a nested signal, or when there's a
4371 pending signal enabled just as the signal handler returns
4372 (leaving the inferior at the step-resume-breakpoint without
4373 actually executing it). Either way continue until the
4374 breakpoint is really hit. */
4379 /* Handle cases caused by hitting a breakpoint. */
4381 CORE_ADDR jmp_buf_pc
;
4382 struct bpstat_what what
;
4384 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4386 if (what
.call_dummy
)
4388 stop_stack_dummy
= what
.call_dummy
;
4391 /* If we hit an internal event that triggers symbol changes, the
4392 current frame will be invalidated within bpstat_what (e.g., if
4393 we hit an internal solib event). Re-fetch it. */
4394 frame
= get_current_frame ();
4395 gdbarch
= get_frame_arch (frame
);
4397 switch (what
.main_action
)
4399 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4400 /* If we hit the breakpoint at longjmp while stepping, we
4401 install a momentary breakpoint at the target of the
4405 fprintf_unfiltered (gdb_stdlog
,
4406 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4408 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4410 if (what
.is_longjmp
)
4412 struct value
*arg_value
;
4414 /* If we set the longjmp breakpoint via a SystemTap probe,
4415 then use it to extract the arguments. The destination
4416 PC is the third argument to the probe. */
4417 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4419 jmp_buf_pc
= value_as_address (arg_value
);
4420 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4421 || !gdbarch_get_longjmp_target (gdbarch
,
4422 frame
, &jmp_buf_pc
))
4425 fprintf_unfiltered (gdb_stdlog
,
4426 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4427 "(!gdbarch_get_longjmp_target)\n");
4432 /* We're going to replace the current step-resume breakpoint
4433 with a longjmp-resume breakpoint. */
4434 delete_step_resume_breakpoint (ecs
->event_thread
);
4436 /* Insert a breakpoint at resume address. */
4437 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4440 check_exception_resume (ecs
, frame
);
4444 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4446 fprintf_unfiltered (gdb_stdlog
,
4447 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4449 if (what
.is_longjmp
)
4451 gdb_assert (ecs
->event_thread
->control
.step_resume_breakpoint
4453 delete_step_resume_breakpoint (ecs
->event_thread
);
4457 /* There are several cases to consider.
4459 1. The initiating frame no longer exists. In this case
4460 we must stop, because the exception has gone too far.
4462 2. The initiating frame exists, and is the same as the
4463 current frame. We stop, because the exception has been
4466 3. The initiating frame exists and is different from
4467 the current frame. This means the exception has been
4468 caught beneath the initiating frame, so keep going. */
4469 struct frame_info
*init_frame
4470 = frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4472 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4474 delete_exception_resume_breakpoint (ecs
->event_thread
);
4478 struct frame_id current_id
4479 = get_frame_id (get_current_frame ());
4480 if (frame_id_eq (current_id
,
4481 ecs
->event_thread
->initiating_frame
))
4483 /* Case 2. Fall through. */
4493 /* For Cases 1 and 2, remove the step-resume breakpoint,
4495 delete_step_resume_breakpoint (ecs
->event_thread
);
4498 ecs
->event_thread
->control
.stop_step
= 1;
4499 print_end_stepping_range_reason ();
4500 stop_stepping (ecs
);
4503 case BPSTAT_WHAT_SINGLE
:
4505 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4506 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4507 /* Still need to check other stuff, at least the case
4508 where we are stepping and step out of the right range. */
4511 case BPSTAT_WHAT_STEP_RESUME
:
4513 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4515 delete_step_resume_breakpoint (ecs
->event_thread
);
4516 if (ecs
->event_thread
->control
.proceed_to_finish
4517 && execution_direction
== EXEC_REVERSE
)
4519 struct thread_info
*tp
= ecs
->event_thread
;
4521 /* We are finishing a function in reverse, and just hit
4522 the step-resume breakpoint at the start address of the
4523 function, and we're almost there -- just need to back
4524 up by one more single-step, which should take us back
4525 to the function call. */
4526 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4530 fill_in_stop_func (gdbarch
, ecs
);
4531 if (stop_pc
== ecs
->stop_func_start
4532 && execution_direction
== EXEC_REVERSE
)
4534 /* We are stepping over a function call in reverse, and
4535 just hit the step-resume breakpoint at the start
4536 address of the function. Go back to single-stepping,
4537 which should take us back to the function call. */
4538 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4544 case BPSTAT_WHAT_STOP_NOISY
:
4546 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4547 stop_print_frame
= 1;
4549 /* We are about to nuke the step_resume_breakpointt via the
4550 cleanup chain, so no need to worry about it here. */
4552 stop_stepping (ecs
);
4555 case BPSTAT_WHAT_STOP_SILENT
:
4557 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4558 stop_print_frame
= 0;
4560 /* We are about to nuke the step_resume_breakpoin via the
4561 cleanup chain, so no need to worry about it here. */
4563 stop_stepping (ecs
);
4566 case BPSTAT_WHAT_HP_STEP_RESUME
:
4568 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4570 delete_step_resume_breakpoint (ecs
->event_thread
);
4571 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4573 /* Back when the step-resume breakpoint was inserted, we
4574 were trying to single-step off a breakpoint. Go back
4576 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4577 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4583 case BPSTAT_WHAT_KEEP_CHECKING
:
4588 /* We come here if we hit a breakpoint but should not
4589 stop for it. Possibly we also were stepping
4590 and should stop for that. So fall through and
4591 test for stepping. But, if not stepping,
4594 /* In all-stop mode, if we're currently stepping but have stopped in
4595 some other thread, we need to switch back to the stepped thread. */
4598 struct thread_info
*tp
;
4600 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
4604 /* However, if the current thread is blocked on some internal
4605 breakpoint, and we simply need to step over that breakpoint
4606 to get it going again, do that first. */
4607 if ((ecs
->event_thread
->control
.trap_expected
4608 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
4609 || ecs
->event_thread
->stepping_over_breakpoint
)
4615 /* If the stepping thread exited, then don't try to switch
4616 back and resume it, which could fail in several different
4617 ways depending on the target. Instead, just keep going.
4619 We can find a stepping dead thread in the thread list in
4622 - The target supports thread exit events, and when the
4623 target tries to delete the thread from the thread list,
4624 inferior_ptid pointed at the exiting thread. In such
4625 case, calling delete_thread does not really remove the
4626 thread from the list; instead, the thread is left listed,
4627 with 'exited' state.
4629 - The target's debug interface does not support thread
4630 exit events, and so we have no idea whatsoever if the
4631 previously stepping thread is still alive. For that
4632 reason, we need to synchronously query the target
4634 if (is_exited (tp
->ptid
)
4635 || !target_thread_alive (tp
->ptid
))
4638 fprintf_unfiltered (gdb_stdlog
,
4639 "infrun: not switching back to "
4640 "stepped thread, it has vanished\n");
4642 delete_thread (tp
->ptid
);
4647 /* Otherwise, we no longer expect a trap in the current thread.
4648 Clear the trap_expected flag before switching back -- this is
4649 what keep_going would do as well, if we called it. */
4650 ecs
->event_thread
->control
.trap_expected
= 0;
4653 fprintf_unfiltered (gdb_stdlog
,
4654 "infrun: switching back to stepped thread\n");
4656 ecs
->event_thread
= tp
;
4657 ecs
->ptid
= tp
->ptid
;
4658 context_switch (ecs
->ptid
);
4664 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4667 fprintf_unfiltered (gdb_stdlog
,
4668 "infrun: step-resume breakpoint is inserted\n");
4670 /* Having a step-resume breakpoint overrides anything
4671 else having to do with stepping commands until
4672 that breakpoint is reached. */
4677 if (ecs
->event_thread
->control
.step_range_end
== 0)
4680 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4681 /* Likewise if we aren't even stepping. */
4686 /* Re-fetch current thread's frame in case the code above caused
4687 the frame cache to be re-initialized, making our FRAME variable
4688 a dangling pointer. */
4689 frame
= get_current_frame ();
4690 gdbarch
= get_frame_arch (frame
);
4691 fill_in_stop_func (gdbarch
, ecs
);
4693 /* If stepping through a line, keep going if still within it.
4695 Note that step_range_end is the address of the first instruction
4696 beyond the step range, and NOT the address of the last instruction
4699 Note also that during reverse execution, we may be stepping
4700 through a function epilogue and therefore must detect when
4701 the current-frame changes in the middle of a line. */
4703 if (stop_pc
>= ecs
->event_thread
->control
.step_range_start
4704 && stop_pc
< ecs
->event_thread
->control
.step_range_end
4705 && (execution_direction
!= EXEC_REVERSE
4706 || frame_id_eq (get_frame_id (frame
),
4707 ecs
->event_thread
->control
.step_frame_id
)))
4711 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4712 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4713 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4715 /* When stepping backward, stop at beginning of line range
4716 (unless it's the function entry point, in which case
4717 keep going back to the call point). */
4718 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4719 && stop_pc
!= ecs
->stop_func_start
4720 && execution_direction
== EXEC_REVERSE
)
4722 ecs
->event_thread
->control
.stop_step
= 1;
4723 print_end_stepping_range_reason ();
4724 stop_stepping (ecs
);
4732 /* We stepped out of the stepping range. */
4734 /* If we are stepping at the source level and entered the runtime
4735 loader dynamic symbol resolution code...
4737 EXEC_FORWARD: we keep on single stepping until we exit the run
4738 time loader code and reach the callee's address.
4740 EXEC_REVERSE: we've already executed the callee (backward), and
4741 the runtime loader code is handled just like any other
4742 undebuggable function call. Now we need only keep stepping
4743 backward through the trampoline code, and that's handled further
4744 down, so there is nothing for us to do here. */
4746 if (execution_direction
!= EXEC_REVERSE
4747 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4748 && in_solib_dynsym_resolve_code (stop_pc
))
4750 CORE_ADDR pc_after_resolver
=
4751 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
4754 fprintf_unfiltered (gdb_stdlog
,
4755 "infrun: stepped into dynsym resolve code\n");
4757 if (pc_after_resolver
)
4759 /* Set up a step-resume breakpoint at the address
4760 indicated by SKIP_SOLIB_RESOLVER. */
4761 struct symtab_and_line sr_sal
;
4764 sr_sal
.pc
= pc_after_resolver
;
4765 sr_sal
.pspace
= get_frame_program_space (frame
);
4767 insert_step_resume_breakpoint_at_sal (gdbarch
,
4768 sr_sal
, null_frame_id
);
4775 if (ecs
->event_thread
->control
.step_range_end
!= 1
4776 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4777 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4778 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
4781 fprintf_unfiltered (gdb_stdlog
,
4782 "infrun: stepped into signal trampoline\n");
4783 /* The inferior, while doing a "step" or "next", has ended up in
4784 a signal trampoline (either by a signal being delivered or by
4785 the signal handler returning). Just single-step until the
4786 inferior leaves the trampoline (either by calling the handler
4792 /* If we're in the return path from a shared library trampoline,
4793 we want to proceed through the trampoline when stepping. */
4794 /* macro/2012-04-25: This needs to come before the subroutine
4795 call check below as on some targets return trampolines look
4796 like subroutine calls (MIPS16 return thunks). */
4797 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4798 stop_pc
, ecs
->stop_func_name
)
4799 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
4801 /* Determine where this trampoline returns. */
4802 CORE_ADDR real_stop_pc
;
4804 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4807 fprintf_unfiltered (gdb_stdlog
,
4808 "infrun: stepped into solib return tramp\n");
4810 /* Only proceed through if we know where it's going. */
4813 /* And put the step-breakpoint there and go until there. */
4814 struct symtab_and_line sr_sal
;
4816 init_sal (&sr_sal
); /* initialize to zeroes */
4817 sr_sal
.pc
= real_stop_pc
;
4818 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4819 sr_sal
.pspace
= get_frame_program_space (frame
);
4821 /* Do not specify what the fp should be when we stop since
4822 on some machines the prologue is where the new fp value
4824 insert_step_resume_breakpoint_at_sal (gdbarch
,
4825 sr_sal
, null_frame_id
);
4827 /* Restart without fiddling with the step ranges or
4834 /* Check for subroutine calls. The check for the current frame
4835 equalling the step ID is not necessary - the check of the
4836 previous frame's ID is sufficient - but it is a common case and
4837 cheaper than checking the previous frame's ID.
4839 NOTE: frame_id_eq will never report two invalid frame IDs as
4840 being equal, so to get into this block, both the current and
4841 previous frame must have valid frame IDs. */
4842 /* The outer_frame_id check is a heuristic to detect stepping
4843 through startup code. If we step over an instruction which
4844 sets the stack pointer from an invalid value to a valid value,
4845 we may detect that as a subroutine call from the mythical
4846 "outermost" function. This could be fixed by marking
4847 outermost frames as !stack_p,code_p,special_p. Then the
4848 initial outermost frame, before sp was valid, would
4849 have code_addr == &_start. See the comment in frame_id_eq
4851 if (!frame_id_eq (get_stack_frame_id (frame
),
4852 ecs
->event_thread
->control
.step_stack_frame_id
)
4853 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4854 ecs
->event_thread
->control
.step_stack_frame_id
)
4855 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
4857 || step_start_function
!= find_pc_function (stop_pc
))))
4859 CORE_ADDR real_stop_pc
;
4862 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
4864 if ((ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
4865 || ((ecs
->event_thread
->control
.step_range_end
== 1)
4866 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
4867 ecs
->stop_func_start
)))
4869 /* I presume that step_over_calls is only 0 when we're
4870 supposed to be stepping at the assembly language level
4871 ("stepi"). Just stop. */
4872 /* Also, maybe we just did a "nexti" inside a prolog, so we
4873 thought it was a subroutine call but it was not. Stop as
4875 /* And this works the same backward as frontward. MVS */
4876 ecs
->event_thread
->control
.stop_step
= 1;
4877 print_end_stepping_range_reason ();
4878 stop_stepping (ecs
);
4882 /* Reverse stepping through solib trampolines. */
4884 if (execution_direction
== EXEC_REVERSE
4885 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
4886 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4887 || (ecs
->stop_func_start
== 0
4888 && in_solib_dynsym_resolve_code (stop_pc
))))
4890 /* Any solib trampoline code can be handled in reverse
4891 by simply continuing to single-step. We have already
4892 executed the solib function (backwards), and a few
4893 steps will take us back through the trampoline to the
4899 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4901 /* We're doing a "next".
4903 Normal (forward) execution: set a breakpoint at the
4904 callee's return address (the address at which the caller
4907 Reverse (backward) execution. set the step-resume
4908 breakpoint at the start of the function that we just
4909 stepped into (backwards), and continue to there. When we
4910 get there, we'll need to single-step back to the caller. */
4912 if (execution_direction
== EXEC_REVERSE
)
4914 struct symtab_and_line sr_sal
;
4916 /* Normal function call return (static or dynamic). */
4918 sr_sal
.pc
= ecs
->stop_func_start
;
4919 sr_sal
.pspace
= get_frame_program_space (frame
);
4920 insert_step_resume_breakpoint_at_sal (gdbarch
,
4921 sr_sal
, null_frame_id
);
4924 insert_step_resume_breakpoint_at_caller (frame
);
4930 /* If we are in a function call trampoline (a stub between the
4931 calling routine and the real function), locate the real
4932 function. That's what tells us (a) whether we want to step
4933 into it at all, and (b) what prologue we want to run to the
4934 end of, if we do step into it. */
4935 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
4936 if (real_stop_pc
== 0)
4937 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4938 if (real_stop_pc
!= 0)
4939 ecs
->stop_func_start
= real_stop_pc
;
4941 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
4943 struct symtab_and_line sr_sal
;
4946 sr_sal
.pc
= ecs
->stop_func_start
;
4947 sr_sal
.pspace
= get_frame_program_space (frame
);
4949 insert_step_resume_breakpoint_at_sal (gdbarch
,
4950 sr_sal
, null_frame_id
);
4955 /* If we have line number information for the function we are
4956 thinking of stepping into and the function isn't on the skip
4959 If there are several symtabs at that PC (e.g. with include
4960 files), just want to know whether *any* of them have line
4961 numbers. find_pc_line handles this. */
4963 struct symtab_and_line tmp_sal
;
4965 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4966 if (tmp_sal
.line
!= 0
4967 && !function_pc_is_marked_for_skip (ecs
->stop_func_start
))
4969 if (execution_direction
== EXEC_REVERSE
)
4970 handle_step_into_function_backward (gdbarch
, ecs
);
4972 handle_step_into_function (gdbarch
, ecs
);
4977 /* If we have no line number and the step-stop-if-no-debug is
4978 set, we stop the step so that the user has a chance to switch
4979 in assembly mode. */
4980 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4981 && step_stop_if_no_debug
)
4983 ecs
->event_thread
->control
.stop_step
= 1;
4984 print_end_stepping_range_reason ();
4985 stop_stepping (ecs
);
4989 if (execution_direction
== EXEC_REVERSE
)
4991 /* Set a breakpoint at callee's start address.
4992 From there we can step once and be back in the caller. */
4993 struct symtab_and_line sr_sal
;
4996 sr_sal
.pc
= ecs
->stop_func_start
;
4997 sr_sal
.pspace
= get_frame_program_space (frame
);
4998 insert_step_resume_breakpoint_at_sal (gdbarch
,
4999 sr_sal
, null_frame_id
);
5002 /* Set a breakpoint at callee's return address (the address
5003 at which the caller will resume). */
5004 insert_step_resume_breakpoint_at_caller (frame
);
5010 /* Reverse stepping through solib trampolines. */
5012 if (execution_direction
== EXEC_REVERSE
5013 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5015 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5016 || (ecs
->stop_func_start
== 0
5017 && in_solib_dynsym_resolve_code (stop_pc
)))
5019 /* Any solib trampoline code can be handled in reverse
5020 by simply continuing to single-step. We have already
5021 executed the solib function (backwards), and a few
5022 steps will take us back through the trampoline to the
5027 else if (in_solib_dynsym_resolve_code (stop_pc
))
5029 /* Stepped backward into the solib dynsym resolver.
5030 Set a breakpoint at its start and continue, then
5031 one more step will take us out. */
5032 struct symtab_and_line sr_sal
;
5035 sr_sal
.pc
= ecs
->stop_func_start
;
5036 sr_sal
.pspace
= get_frame_program_space (frame
);
5037 insert_step_resume_breakpoint_at_sal (gdbarch
,
5038 sr_sal
, null_frame_id
);
5044 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5046 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5047 the trampoline processing logic, however, there are some trampolines
5048 that have no names, so we should do trampoline handling first. */
5049 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5050 && ecs
->stop_func_name
== NULL
5051 && stop_pc_sal
.line
== 0)
5054 fprintf_unfiltered (gdb_stdlog
,
5055 "infrun: stepped into undebuggable function\n");
5057 /* The inferior just stepped into, or returned to, an
5058 undebuggable function (where there is no debugging information
5059 and no line number corresponding to the address where the
5060 inferior stopped). Since we want to skip this kind of code,
5061 we keep going until the inferior returns from this
5062 function - unless the user has asked us not to (via
5063 set step-mode) or we no longer know how to get back
5064 to the call site. */
5065 if (step_stop_if_no_debug
5066 || !frame_id_p (frame_unwind_caller_id (frame
)))
5068 /* If we have no line number and the step-stop-if-no-debug
5069 is set, we stop the step so that the user has a chance to
5070 switch in assembly mode. */
5071 ecs
->event_thread
->control
.stop_step
= 1;
5072 print_end_stepping_range_reason ();
5073 stop_stepping (ecs
);
5078 /* Set a breakpoint at callee's return address (the address
5079 at which the caller will resume). */
5080 insert_step_resume_breakpoint_at_caller (frame
);
5086 if (ecs
->event_thread
->control
.step_range_end
== 1)
5088 /* It is stepi or nexti. We always want to stop stepping after
5091 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5092 ecs
->event_thread
->control
.stop_step
= 1;
5093 print_end_stepping_range_reason ();
5094 stop_stepping (ecs
);
5098 if (stop_pc_sal
.line
== 0)
5100 /* We have no line number information. That means to stop
5101 stepping (does this always happen right after one instruction,
5102 when we do "s" in a function with no line numbers,
5103 or can this happen as a result of a return or longjmp?). */
5105 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5106 ecs
->event_thread
->control
.stop_step
= 1;
5107 print_end_stepping_range_reason ();
5108 stop_stepping (ecs
);
5112 /* Look for "calls" to inlined functions, part one. If the inline
5113 frame machinery detected some skipped call sites, we have entered
5114 a new inline function. */
5116 if (frame_id_eq (get_frame_id (get_current_frame ()),
5117 ecs
->event_thread
->control
.step_frame_id
)
5118 && inline_skipped_frames (ecs
->ptid
))
5120 struct symtab_and_line call_sal
;
5123 fprintf_unfiltered (gdb_stdlog
,
5124 "infrun: stepped into inlined function\n");
5126 find_frame_sal (get_current_frame (), &call_sal
);
5128 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5130 /* For "step", we're going to stop. But if the call site
5131 for this inlined function is on the same source line as
5132 we were previously stepping, go down into the function
5133 first. Otherwise stop at the call site. */
5135 if (call_sal
.line
== ecs
->event_thread
->current_line
5136 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5137 step_into_inline_frame (ecs
->ptid
);
5139 ecs
->event_thread
->control
.stop_step
= 1;
5140 print_end_stepping_range_reason ();
5141 stop_stepping (ecs
);
5146 /* For "next", we should stop at the call site if it is on a
5147 different source line. Otherwise continue through the
5148 inlined function. */
5149 if (call_sal
.line
== ecs
->event_thread
->current_line
5150 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5154 ecs
->event_thread
->control
.stop_step
= 1;
5155 print_end_stepping_range_reason ();
5156 stop_stepping (ecs
);
5162 /* Look for "calls" to inlined functions, part two. If we are still
5163 in the same real function we were stepping through, but we have
5164 to go further up to find the exact frame ID, we are stepping
5165 through a more inlined call beyond its call site. */
5167 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5168 && !frame_id_eq (get_frame_id (get_current_frame ()),
5169 ecs
->event_thread
->control
.step_frame_id
)
5170 && stepped_in_from (get_current_frame (),
5171 ecs
->event_thread
->control
.step_frame_id
))
5174 fprintf_unfiltered (gdb_stdlog
,
5175 "infrun: stepping through inlined function\n");
5177 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5181 ecs
->event_thread
->control
.stop_step
= 1;
5182 print_end_stepping_range_reason ();
5183 stop_stepping (ecs
);
5188 if ((stop_pc
== stop_pc_sal
.pc
)
5189 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5190 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5192 /* We are at the start of a different line. So stop. Note that
5193 we don't stop if we step into the middle of a different line.
5194 That is said to make things like for (;;) statements work
5197 fprintf_unfiltered (gdb_stdlog
,
5198 "infrun: stepped to a different line\n");
5199 ecs
->event_thread
->control
.stop_step
= 1;
5200 print_end_stepping_range_reason ();
5201 stop_stepping (ecs
);
5205 /* We aren't done stepping.
5207 Optimize by setting the stepping range to the line.
5208 (We might not be in the original line, but if we entered a
5209 new line in mid-statement, we continue stepping. This makes
5210 things like for(;;) statements work better.) */
5212 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5213 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5214 set_step_info (frame
, stop_pc_sal
);
5217 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5221 /* Is thread TP in the middle of single-stepping? */
5224 currently_stepping (struct thread_info
*tp
)
5226 return ((tp
->control
.step_range_end
5227 && tp
->control
.step_resume_breakpoint
== NULL
)
5228 || tp
->control
.trap_expected
5229 || bpstat_should_step ());
5232 /* Returns true if any thread *but* the one passed in "data" is in the
5233 middle of stepping or of handling a "next". */
5236 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
5241 return (tp
->control
.step_range_end
5242 || tp
->control
.trap_expected
);
5245 /* Inferior has stepped into a subroutine call with source code that
5246 we should not step over. Do step to the first line of code in
5250 handle_step_into_function (struct gdbarch
*gdbarch
,
5251 struct execution_control_state
*ecs
)
5254 struct symtab_and_line stop_func_sal
, sr_sal
;
5256 fill_in_stop_func (gdbarch
, ecs
);
5258 s
= find_pc_symtab (stop_pc
);
5259 if (s
&& s
->language
!= language_asm
)
5260 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5261 ecs
->stop_func_start
);
5263 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5264 /* Use the step_resume_break to step until the end of the prologue,
5265 even if that involves jumps (as it seems to on the vax under
5267 /* If the prologue ends in the middle of a source line, continue to
5268 the end of that source line (if it is still within the function).
5269 Otherwise, just go to end of prologue. */
5270 if (stop_func_sal
.end
5271 && stop_func_sal
.pc
!= ecs
->stop_func_start
5272 && stop_func_sal
.end
< ecs
->stop_func_end
)
5273 ecs
->stop_func_start
= stop_func_sal
.end
;
5275 /* Architectures which require breakpoint adjustment might not be able
5276 to place a breakpoint at the computed address. If so, the test
5277 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5278 ecs->stop_func_start to an address at which a breakpoint may be
5279 legitimately placed.
5281 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5282 made, GDB will enter an infinite loop when stepping through
5283 optimized code consisting of VLIW instructions which contain
5284 subinstructions corresponding to different source lines. On
5285 FR-V, it's not permitted to place a breakpoint on any but the
5286 first subinstruction of a VLIW instruction. When a breakpoint is
5287 set, GDB will adjust the breakpoint address to the beginning of
5288 the VLIW instruction. Thus, we need to make the corresponding
5289 adjustment here when computing the stop address. */
5291 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5293 ecs
->stop_func_start
5294 = gdbarch_adjust_breakpoint_address (gdbarch
,
5295 ecs
->stop_func_start
);
5298 if (ecs
->stop_func_start
== stop_pc
)
5300 /* We are already there: stop now. */
5301 ecs
->event_thread
->control
.stop_step
= 1;
5302 print_end_stepping_range_reason ();
5303 stop_stepping (ecs
);
5308 /* Put the step-breakpoint there and go until there. */
5309 init_sal (&sr_sal
); /* initialize to zeroes */
5310 sr_sal
.pc
= ecs
->stop_func_start
;
5311 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5312 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5314 /* Do not specify what the fp should be when we stop since on
5315 some machines the prologue is where the new fp value is
5317 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5319 /* And make sure stepping stops right away then. */
5320 ecs
->event_thread
->control
.step_range_end
5321 = ecs
->event_thread
->control
.step_range_start
;
5326 /* Inferior has stepped backward into a subroutine call with source
5327 code that we should not step over. Do step to the beginning of the
5328 last line of code in it. */
5331 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5332 struct execution_control_state
*ecs
)
5335 struct symtab_and_line stop_func_sal
;
5337 fill_in_stop_func (gdbarch
, ecs
);
5339 s
= find_pc_symtab (stop_pc
);
5340 if (s
&& s
->language
!= language_asm
)
5341 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5342 ecs
->stop_func_start
);
5344 stop_func_sal
= find_pc_line (stop_pc
, 0);
5346 /* OK, we're just going to keep stepping here. */
5347 if (stop_func_sal
.pc
== stop_pc
)
5349 /* We're there already. Just stop stepping now. */
5350 ecs
->event_thread
->control
.stop_step
= 1;
5351 print_end_stepping_range_reason ();
5352 stop_stepping (ecs
);
5356 /* Else just reset the step range and keep going.
5357 No step-resume breakpoint, they don't work for
5358 epilogues, which can have multiple entry paths. */
5359 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5360 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5366 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5367 This is used to both functions and to skip over code. */
5370 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5371 struct symtab_and_line sr_sal
,
5372 struct frame_id sr_id
,
5373 enum bptype sr_type
)
5375 /* There should never be more than one step-resume or longjmp-resume
5376 breakpoint per thread, so we should never be setting a new
5377 step_resume_breakpoint when one is already active. */
5378 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5379 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5382 fprintf_unfiltered (gdb_stdlog
,
5383 "infrun: inserting step-resume breakpoint at %s\n",
5384 paddress (gdbarch
, sr_sal
.pc
));
5386 inferior_thread ()->control
.step_resume_breakpoint
5387 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5391 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5392 struct symtab_and_line sr_sal
,
5393 struct frame_id sr_id
)
5395 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5400 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5401 This is used to skip a potential signal handler.
5403 This is called with the interrupted function's frame. The signal
5404 handler, when it returns, will resume the interrupted function at
5408 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5410 struct symtab_and_line sr_sal
;
5411 struct gdbarch
*gdbarch
;
5413 gdb_assert (return_frame
!= NULL
);
5414 init_sal (&sr_sal
); /* initialize to zeros */
5416 gdbarch
= get_frame_arch (return_frame
);
5417 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5418 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5419 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5421 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5422 get_stack_frame_id (return_frame
),
5426 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5427 is used to skip a function after stepping into it (for "next" or if
5428 the called function has no debugging information).
5430 The current function has almost always been reached by single
5431 stepping a call or return instruction. NEXT_FRAME belongs to the
5432 current function, and the breakpoint will be set at the caller's
5435 This is a separate function rather than reusing
5436 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5437 get_prev_frame, which may stop prematurely (see the implementation
5438 of frame_unwind_caller_id for an example). */
5441 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5443 struct symtab_and_line sr_sal
;
5444 struct gdbarch
*gdbarch
;
5446 /* We shouldn't have gotten here if we don't know where the call site
5448 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5450 init_sal (&sr_sal
); /* initialize to zeros */
5452 gdbarch
= frame_unwind_caller_arch (next_frame
);
5453 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5454 frame_unwind_caller_pc (next_frame
));
5455 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5456 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5458 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5459 frame_unwind_caller_id (next_frame
));
5462 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5463 new breakpoint at the target of a jmp_buf. The handling of
5464 longjmp-resume uses the same mechanisms used for handling
5465 "step-resume" breakpoints. */
5468 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5470 /* There should never be more than one step-resume or longjmp-resume
5471 breakpoint per thread, so we should never be setting a new
5472 longjmp_resume_breakpoint when one is already active. */
5473 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5476 fprintf_unfiltered (gdb_stdlog
,
5477 "infrun: inserting longjmp-resume breakpoint at %s\n",
5478 paddress (gdbarch
, pc
));
5480 inferior_thread ()->control
.step_resume_breakpoint
=
5481 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5484 /* Insert an exception resume breakpoint. TP is the thread throwing
5485 the exception. The block B is the block of the unwinder debug hook
5486 function. FRAME is the frame corresponding to the call to this
5487 function. SYM is the symbol of the function argument holding the
5488 target PC of the exception. */
5491 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5493 struct frame_info
*frame
,
5496 volatile struct gdb_exception e
;
5498 /* We want to ignore errors here. */
5499 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5501 struct symbol
*vsym
;
5502 struct value
*value
;
5504 struct breakpoint
*bp
;
5506 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5507 value
= read_var_value (vsym
, frame
);
5508 /* If the value was optimized out, revert to the old behavior. */
5509 if (! value_optimized_out (value
))
5511 handler
= value_as_address (value
);
5514 fprintf_unfiltered (gdb_stdlog
,
5515 "infrun: exception resume at %lx\n",
5516 (unsigned long) handler
);
5518 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5519 handler
, bp_exception_resume
);
5521 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5524 bp
->thread
= tp
->num
;
5525 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5530 /* A helper for check_exception_resume that sets an
5531 exception-breakpoint based on a SystemTap probe. */
5534 insert_exception_resume_from_probe (struct thread_info
*tp
,
5535 const struct probe
*probe
,
5536 struct objfile
*objfile
,
5537 struct frame_info
*frame
)
5539 struct value
*arg_value
;
5541 struct breakpoint
*bp
;
5543 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
5547 handler
= value_as_address (arg_value
);
5550 fprintf_unfiltered (gdb_stdlog
,
5551 "infrun: exception resume at %s\n",
5552 paddress (get_objfile_arch (objfile
),
5555 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5556 handler
, bp_exception_resume
);
5557 bp
->thread
= tp
->num
;
5558 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5561 /* This is called when an exception has been intercepted. Check to
5562 see whether the exception's destination is of interest, and if so,
5563 set an exception resume breakpoint there. */
5566 check_exception_resume (struct execution_control_state
*ecs
,
5567 struct frame_info
*frame
)
5569 volatile struct gdb_exception e
;
5570 struct objfile
*objfile
;
5571 const struct probe
*probe
;
5572 struct symbol
*func
;
5574 /* First see if this exception unwinding breakpoint was set via a
5575 SystemTap probe point. If so, the probe has two arguments: the
5576 CFA and the HANDLER. We ignore the CFA, extract the handler, and
5577 set a breakpoint there. */
5578 probe
= find_probe_by_pc (get_frame_pc (frame
), &objfile
);
5581 insert_exception_resume_from_probe (ecs
->event_thread
, probe
,
5586 func
= get_frame_function (frame
);
5590 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5593 struct block_iterator iter
;
5597 /* The exception breakpoint is a thread-specific breakpoint on
5598 the unwinder's debug hook, declared as:
5600 void _Unwind_DebugHook (void *cfa, void *handler);
5602 The CFA argument indicates the frame to which control is
5603 about to be transferred. HANDLER is the destination PC.
5605 We ignore the CFA and set a temporary breakpoint at HANDLER.
5606 This is not extremely efficient but it avoids issues in gdb
5607 with computing the DWARF CFA, and it also works even in weird
5608 cases such as throwing an exception from inside a signal
5611 b
= SYMBOL_BLOCK_VALUE (func
);
5612 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
5614 if (!SYMBOL_IS_ARGUMENT (sym
))
5621 insert_exception_resume_breakpoint (ecs
->event_thread
,
5630 stop_stepping (struct execution_control_state
*ecs
)
5633 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
5635 /* Let callers know we don't want to wait for the inferior anymore. */
5636 ecs
->wait_some_more
= 0;
5639 /* This function handles various cases where we need to continue
5640 waiting for the inferior. */
5641 /* (Used to be the keep_going: label in the old wait_for_inferior). */
5644 keep_going (struct execution_control_state
*ecs
)
5646 /* Make sure normal_stop is called if we get a QUIT handled before
5648 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
5650 /* Save the pc before execution, to compare with pc after stop. */
5651 ecs
->event_thread
->prev_pc
5652 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5654 /* If we did not do break;, it means we should keep running the
5655 inferior and not return to debugger. */
5657 if (ecs
->event_thread
->control
.trap_expected
5658 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5660 /* We took a signal (which we are supposed to pass through to
5661 the inferior, else we'd not get here) and we haven't yet
5662 gotten our trap. Simply continue. */
5664 discard_cleanups (old_cleanups
);
5665 resume (currently_stepping (ecs
->event_thread
),
5666 ecs
->event_thread
->suspend
.stop_signal
);
5670 /* Either the trap was not expected, but we are continuing
5671 anyway (the user asked that this signal be passed to the
5674 The signal was SIGTRAP, e.g. it was our signal, but we
5675 decided we should resume from it.
5677 We're going to run this baby now!
5679 Note that insert_breakpoints won't try to re-insert
5680 already inserted breakpoints. Therefore, we don't
5681 care if breakpoints were already inserted, or not. */
5683 if (ecs
->event_thread
->stepping_over_breakpoint
)
5685 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
5687 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
5688 /* Since we can't do a displaced step, we have to remove
5689 the breakpoint while we step it. To keep things
5690 simple, we remove them all. */
5691 remove_breakpoints ();
5695 volatile struct gdb_exception e
;
5697 /* Stop stepping when inserting breakpoints
5699 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5701 insert_breakpoints ();
5705 exception_print (gdb_stderr
, e
);
5706 stop_stepping (ecs
);
5711 ecs
->event_thread
->control
.trap_expected
5712 = ecs
->event_thread
->stepping_over_breakpoint
;
5714 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
5715 specifies that such a signal should be delivered to the
5718 Typically, this would occure when a user is debugging a
5719 target monitor on a simulator: the target monitor sets a
5720 breakpoint; the simulator encounters this break-point and
5721 halts the simulation handing control to GDB; GDB, noteing
5722 that the break-point isn't valid, returns control back to the
5723 simulator; the simulator then delivers the hardware
5724 equivalent of a SIGNAL_TRAP to the program being debugged. */
5726 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5727 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5728 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5730 discard_cleanups (old_cleanups
);
5731 resume (currently_stepping (ecs
->event_thread
),
5732 ecs
->event_thread
->suspend
.stop_signal
);
5735 prepare_to_wait (ecs
);
5738 /* This function normally comes after a resume, before
5739 handle_inferior_event exits. It takes care of any last bits of
5740 housekeeping, and sets the all-important wait_some_more flag. */
5743 prepare_to_wait (struct execution_control_state
*ecs
)
5746 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
5748 /* This is the old end of the while loop. Let everybody know we
5749 want to wait for the inferior some more and get called again
5751 ecs
->wait_some_more
= 1;
5754 /* Several print_*_reason functions to print why the inferior has stopped.
5755 We always print something when the inferior exits, or receives a signal.
5756 The rest of the cases are dealt with later on in normal_stop and
5757 print_it_typical. Ideally there should be a call to one of these
5758 print_*_reason functions functions from handle_inferior_event each time
5759 stop_stepping is called. */
5761 /* Print why the inferior has stopped.
5762 We are done with a step/next/si/ni command, print why the inferior has
5763 stopped. For now print nothing. Print a message only if not in the middle
5764 of doing a "step n" operation for n > 1. */
5767 print_end_stepping_range_reason (void)
5769 if ((!inferior_thread ()->step_multi
5770 || !inferior_thread ()->control
.stop_step
)
5771 && ui_out_is_mi_like_p (current_uiout
))
5772 ui_out_field_string (current_uiout
, "reason",
5773 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
5776 /* The inferior was terminated by a signal, print why it stopped. */
5779 print_signal_exited_reason (enum gdb_signal siggnal
)
5781 struct ui_out
*uiout
= current_uiout
;
5783 annotate_signalled ();
5784 if (ui_out_is_mi_like_p (uiout
))
5786 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
5787 ui_out_text (uiout
, "\nProgram terminated with signal ");
5788 annotate_signal_name ();
5789 ui_out_field_string (uiout
, "signal-name",
5790 gdb_signal_to_name (siggnal
));
5791 annotate_signal_name_end ();
5792 ui_out_text (uiout
, ", ");
5793 annotate_signal_string ();
5794 ui_out_field_string (uiout
, "signal-meaning",
5795 gdb_signal_to_string (siggnal
));
5796 annotate_signal_string_end ();
5797 ui_out_text (uiout
, ".\n");
5798 ui_out_text (uiout
, "The program no longer exists.\n");
5801 /* The inferior program is finished, print why it stopped. */
5804 print_exited_reason (int exitstatus
)
5806 struct inferior
*inf
= current_inferior ();
5807 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
5808 struct ui_out
*uiout
= current_uiout
;
5810 annotate_exited (exitstatus
);
5813 if (ui_out_is_mi_like_p (uiout
))
5814 ui_out_field_string (uiout
, "reason",
5815 async_reason_lookup (EXEC_ASYNC_EXITED
));
5816 ui_out_text (uiout
, "[Inferior ");
5817 ui_out_text (uiout
, plongest (inf
->num
));
5818 ui_out_text (uiout
, " (");
5819 ui_out_text (uiout
, pidstr
);
5820 ui_out_text (uiout
, ") exited with code ");
5821 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
5822 ui_out_text (uiout
, "]\n");
5826 if (ui_out_is_mi_like_p (uiout
))
5828 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
5829 ui_out_text (uiout
, "[Inferior ");
5830 ui_out_text (uiout
, plongest (inf
->num
));
5831 ui_out_text (uiout
, " (");
5832 ui_out_text (uiout
, pidstr
);
5833 ui_out_text (uiout
, ") exited normally]\n");
5835 /* Support the --return-child-result option. */
5836 return_child_result_value
= exitstatus
;
5839 /* Signal received, print why the inferior has stopped. The signal table
5840 tells us to print about it. */
5843 print_signal_received_reason (enum gdb_signal siggnal
)
5845 struct ui_out
*uiout
= current_uiout
;
5849 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
5851 struct thread_info
*t
= inferior_thread ();
5853 ui_out_text (uiout
, "\n[");
5854 ui_out_field_string (uiout
, "thread-name",
5855 target_pid_to_str (t
->ptid
));
5856 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
5857 ui_out_text (uiout
, " stopped");
5861 ui_out_text (uiout
, "\nProgram received signal ");
5862 annotate_signal_name ();
5863 if (ui_out_is_mi_like_p (uiout
))
5865 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
5866 ui_out_field_string (uiout
, "signal-name",
5867 gdb_signal_to_name (siggnal
));
5868 annotate_signal_name_end ();
5869 ui_out_text (uiout
, ", ");
5870 annotate_signal_string ();
5871 ui_out_field_string (uiout
, "signal-meaning",
5872 gdb_signal_to_string (siggnal
));
5873 annotate_signal_string_end ();
5875 ui_out_text (uiout
, ".\n");
5878 /* Reverse execution: target ran out of history info, print why the inferior
5882 print_no_history_reason (void)
5884 ui_out_text (current_uiout
, "\nNo more reverse-execution history.\n");
5887 /* Here to return control to GDB when the inferior stops for real.
5888 Print appropriate messages, remove breakpoints, give terminal our modes.
5890 STOP_PRINT_FRAME nonzero means print the executing frame
5891 (pc, function, args, file, line number and line text).
5892 BREAKPOINTS_FAILED nonzero means stop was due to error
5893 attempting to insert breakpoints. */
5898 struct target_waitstatus last
;
5900 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
5902 get_last_target_status (&last_ptid
, &last
);
5904 /* If an exception is thrown from this point on, make sure to
5905 propagate GDB's knowledge of the executing state to the
5906 frontend/user running state. A QUIT is an easy exception to see
5907 here, so do this before any filtered output. */
5909 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
5910 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
5911 && last
.kind
!= TARGET_WAITKIND_EXITED
5912 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
5913 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
5915 /* In non-stop mode, we don't want GDB to switch threads behind the
5916 user's back, to avoid races where the user is typing a command to
5917 apply to thread x, but GDB switches to thread y before the user
5918 finishes entering the command. */
5920 /* As with the notification of thread events, we want to delay
5921 notifying the user that we've switched thread context until
5922 the inferior actually stops.
5924 There's no point in saying anything if the inferior has exited.
5925 Note that SIGNALLED here means "exited with a signal", not
5926 "received a signal". */
5928 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
5929 && target_has_execution
5930 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5931 && last
.kind
!= TARGET_WAITKIND_EXITED
5932 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
5934 target_terminal_ours_for_output ();
5935 printf_filtered (_("[Switching to %s]\n"),
5936 target_pid_to_str (inferior_ptid
));
5937 annotate_thread_changed ();
5938 previous_inferior_ptid
= inferior_ptid
;
5941 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
5943 gdb_assert (sync_execution
|| !target_can_async_p ());
5945 target_terminal_ours_for_output ();
5946 printf_filtered (_("No unwaited-for children left.\n"));
5949 if (!breakpoints_always_inserted_mode () && target_has_execution
)
5951 if (remove_breakpoints ())
5953 target_terminal_ours_for_output ();
5954 printf_filtered (_("Cannot remove breakpoints because "
5955 "program is no longer writable.\nFurther "
5956 "execution is probably impossible.\n"));
5960 /* If an auto-display called a function and that got a signal,
5961 delete that auto-display to avoid an infinite recursion. */
5963 if (stopped_by_random_signal
)
5964 disable_current_display ();
5966 /* Don't print a message if in the middle of doing a "step n"
5967 operation for n > 1 */
5968 if (target_has_execution
5969 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5970 && last
.kind
!= TARGET_WAITKIND_EXITED
5971 && inferior_thread ()->step_multi
5972 && inferior_thread ()->control
.stop_step
)
5975 target_terminal_ours ();
5976 async_enable_stdin ();
5978 /* Set the current source location. This will also happen if we
5979 display the frame below, but the current SAL will be incorrect
5980 during a user hook-stop function. */
5981 if (has_stack_frames () && !stop_stack_dummy
)
5982 set_current_sal_from_frame (get_current_frame (), 1);
5984 /* Let the user/frontend see the threads as stopped. */
5985 do_cleanups (old_chain
);
5987 /* Look up the hook_stop and run it (CLI internally handles problem
5988 of stop_command's pre-hook not existing). */
5990 catch_errors (hook_stop_stub
, stop_command
,
5991 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
5993 if (!has_stack_frames ())
5996 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
5997 || last
.kind
== TARGET_WAITKIND_EXITED
)
6000 /* Select innermost stack frame - i.e., current frame is frame 0,
6001 and current location is based on that.
6002 Don't do this on return from a stack dummy routine,
6003 or if the program has exited. */
6005 if (!stop_stack_dummy
)
6007 select_frame (get_current_frame ());
6009 /* Print current location without a level number, if
6010 we have changed functions or hit a breakpoint.
6011 Print source line if we have one.
6012 bpstat_print() contains the logic deciding in detail
6013 what to print, based on the event(s) that just occurred. */
6015 /* If --batch-silent is enabled then there's no need to print the current
6016 source location, and to try risks causing an error message about
6017 missing source files. */
6018 if (stop_print_frame
&& !batch_silent
)
6022 int do_frame_printing
= 1;
6023 struct thread_info
*tp
= inferior_thread ();
6025 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, last
.kind
);
6029 /* FIXME: cagney/2002-12-01: Given that a frame ID does
6030 (or should) carry around the function and does (or
6031 should) use that when doing a frame comparison. */
6032 if (tp
->control
.stop_step
6033 && frame_id_eq (tp
->control
.step_frame_id
,
6034 get_frame_id (get_current_frame ()))
6035 && step_start_function
== find_pc_function (stop_pc
))
6036 source_flag
= SRC_LINE
; /* Finished step, just
6037 print source line. */
6039 source_flag
= SRC_AND_LOC
; /* Print location and
6042 case PRINT_SRC_AND_LOC
:
6043 source_flag
= SRC_AND_LOC
; /* Print location and
6046 case PRINT_SRC_ONLY
:
6047 source_flag
= SRC_LINE
;
6050 source_flag
= SRC_LINE
; /* something bogus */
6051 do_frame_printing
= 0;
6054 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6057 /* The behavior of this routine with respect to the source
6059 SRC_LINE: Print only source line
6060 LOCATION: Print only location
6061 SRC_AND_LOC: Print location and source line. */
6062 if (do_frame_printing
)
6063 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
6065 /* Display the auto-display expressions. */
6070 /* Save the function value return registers, if we care.
6071 We might be about to restore their previous contents. */
6072 if (inferior_thread ()->control
.proceed_to_finish
6073 && execution_direction
!= EXEC_REVERSE
)
6075 /* This should not be necessary. */
6077 regcache_xfree (stop_registers
);
6079 /* NB: The copy goes through to the target picking up the value of
6080 all the registers. */
6081 stop_registers
= regcache_dup (get_current_regcache ());
6084 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6086 /* Pop the empty frame that contains the stack dummy.
6087 This also restores inferior state prior to the call
6088 (struct infcall_suspend_state). */
6089 struct frame_info
*frame
= get_current_frame ();
6091 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6093 /* frame_pop() calls reinit_frame_cache as the last thing it
6094 does which means there's currently no selected frame. We
6095 don't need to re-establish a selected frame if the dummy call
6096 returns normally, that will be done by
6097 restore_infcall_control_state. However, we do have to handle
6098 the case where the dummy call is returning after being
6099 stopped (e.g. the dummy call previously hit a breakpoint).
6100 We can't know which case we have so just always re-establish
6101 a selected frame here. */
6102 select_frame (get_current_frame ());
6106 annotate_stopped ();
6108 /* Suppress the stop observer if we're in the middle of:
6110 - a step n (n > 1), as there still more steps to be done.
6112 - a "finish" command, as the observer will be called in
6113 finish_command_continuation, so it can include the inferior
6114 function's return value.
6116 - calling an inferior function, as we pretend we inferior didn't
6117 run at all. The return value of the call is handled by the
6118 expression evaluator, through call_function_by_hand. */
6120 if (!target_has_execution
6121 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6122 || last
.kind
== TARGET_WAITKIND_EXITED
6123 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6124 || (!(inferior_thread ()->step_multi
6125 && inferior_thread ()->control
.stop_step
)
6126 && !(inferior_thread ()->control
.stop_bpstat
6127 && inferior_thread ()->control
.proceed_to_finish
)
6128 && !inferior_thread ()->control
.in_infcall
))
6130 if (!ptid_equal (inferior_ptid
, null_ptid
))
6131 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6134 observer_notify_normal_stop (NULL
, stop_print_frame
);
6137 if (target_has_execution
)
6139 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6140 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6141 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6142 Delete any breakpoint that is to be deleted at the next stop. */
6143 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6146 /* Try to get rid of automatically added inferiors that are no
6147 longer needed. Keeping those around slows down things linearly.
6148 Note that this never removes the current inferior. */
6153 hook_stop_stub (void *cmd
)
6155 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6160 signal_stop_state (int signo
)
6162 return signal_stop
[signo
];
6166 signal_print_state (int signo
)
6168 return signal_print
[signo
];
6172 signal_pass_state (int signo
)
6174 return signal_program
[signo
];
6178 signal_cache_update (int signo
)
6182 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6183 signal_cache_update (signo
);
6188 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6189 && signal_print
[signo
] == 0
6190 && signal_program
[signo
] == 1);
6194 signal_stop_update (int signo
, int state
)
6196 int ret
= signal_stop
[signo
];
6198 signal_stop
[signo
] = state
;
6199 signal_cache_update (signo
);
6204 signal_print_update (int signo
, int state
)
6206 int ret
= signal_print
[signo
];
6208 signal_print
[signo
] = state
;
6209 signal_cache_update (signo
);
6214 signal_pass_update (int signo
, int state
)
6216 int ret
= signal_program
[signo
];
6218 signal_program
[signo
] = state
;
6219 signal_cache_update (signo
);
6224 sig_print_header (void)
6226 printf_filtered (_("Signal Stop\tPrint\tPass "
6227 "to program\tDescription\n"));
6231 sig_print_info (enum gdb_signal oursig
)
6233 const char *name
= gdb_signal_to_name (oursig
);
6234 int name_padding
= 13 - strlen (name
);
6236 if (name_padding
<= 0)
6239 printf_filtered ("%s", name
);
6240 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6241 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6242 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6243 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6244 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6247 /* Specify how various signals in the inferior should be handled. */
6250 handle_command (char *args
, int from_tty
)
6253 int digits
, wordlen
;
6254 int sigfirst
, signum
, siglast
;
6255 enum gdb_signal oursig
;
6258 unsigned char *sigs
;
6259 struct cleanup
*old_chain
;
6263 error_no_arg (_("signal to handle"));
6266 /* Allocate and zero an array of flags for which signals to handle. */
6268 nsigs
= (int) GDB_SIGNAL_LAST
;
6269 sigs
= (unsigned char *) alloca (nsigs
);
6270 memset (sigs
, 0, nsigs
);
6272 /* Break the command line up into args. */
6274 argv
= gdb_buildargv (args
);
6275 old_chain
= make_cleanup_freeargv (argv
);
6277 /* Walk through the args, looking for signal oursigs, signal names, and
6278 actions. Signal numbers and signal names may be interspersed with
6279 actions, with the actions being performed for all signals cumulatively
6280 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6282 while (*argv
!= NULL
)
6284 wordlen
= strlen (*argv
);
6285 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6289 sigfirst
= siglast
= -1;
6291 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6293 /* Apply action to all signals except those used by the
6294 debugger. Silently skip those. */
6297 siglast
= nsigs
- 1;
6299 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6301 SET_SIGS (nsigs
, sigs
, signal_stop
);
6302 SET_SIGS (nsigs
, sigs
, signal_print
);
6304 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6306 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6308 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6310 SET_SIGS (nsigs
, sigs
, signal_print
);
6312 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6314 SET_SIGS (nsigs
, sigs
, signal_program
);
6316 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6318 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6320 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6322 SET_SIGS (nsigs
, sigs
, signal_program
);
6324 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6326 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6327 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6329 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6331 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6333 else if (digits
> 0)
6335 /* It is numeric. The numeric signal refers to our own
6336 internal signal numbering from target.h, not to host/target
6337 signal number. This is a feature; users really should be
6338 using symbolic names anyway, and the common ones like
6339 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6341 sigfirst
= siglast
= (int)
6342 gdb_signal_from_command (atoi (*argv
));
6343 if ((*argv
)[digits
] == '-')
6346 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6348 if (sigfirst
> siglast
)
6350 /* Bet he didn't figure we'd think of this case... */
6358 oursig
= gdb_signal_from_name (*argv
);
6359 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
6361 sigfirst
= siglast
= (int) oursig
;
6365 /* Not a number and not a recognized flag word => complain. */
6366 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6370 /* If any signal numbers or symbol names were found, set flags for
6371 which signals to apply actions to. */
6373 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6375 switch ((enum gdb_signal
) signum
)
6377 case GDB_SIGNAL_TRAP
:
6378 case GDB_SIGNAL_INT
:
6379 if (!allsigs
&& !sigs
[signum
])
6381 if (query (_("%s is used by the debugger.\n\
6382 Are you sure you want to change it? "),
6383 gdb_signal_to_name ((enum gdb_signal
) signum
)))
6389 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6390 gdb_flush (gdb_stdout
);
6395 case GDB_SIGNAL_DEFAULT
:
6396 case GDB_SIGNAL_UNKNOWN
:
6397 /* Make sure that "all" doesn't print these. */
6408 for (signum
= 0; signum
< nsigs
; signum
++)
6411 signal_cache_update (-1);
6412 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6413 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
6417 /* Show the results. */
6418 sig_print_header ();
6419 for (; signum
< nsigs
; signum
++)
6421 sig_print_info (signum
);
6427 do_cleanups (old_chain
);
6431 xdb_handle_command (char *args
, int from_tty
)
6434 struct cleanup
*old_chain
;
6437 error_no_arg (_("xdb command"));
6439 /* Break the command line up into args. */
6441 argv
= gdb_buildargv (args
);
6442 old_chain
= make_cleanup_freeargv (argv
);
6443 if (argv
[1] != (char *) NULL
)
6448 bufLen
= strlen (argv
[0]) + 20;
6449 argBuf
= (char *) xmalloc (bufLen
);
6453 enum gdb_signal oursig
;
6455 oursig
= gdb_signal_from_name (argv
[0]);
6456 memset (argBuf
, 0, bufLen
);
6457 if (strcmp (argv
[1], "Q") == 0)
6458 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6461 if (strcmp (argv
[1], "s") == 0)
6463 if (!signal_stop
[oursig
])
6464 sprintf (argBuf
, "%s %s", argv
[0], "stop");
6466 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
6468 else if (strcmp (argv
[1], "i") == 0)
6470 if (!signal_program
[oursig
])
6471 sprintf (argBuf
, "%s %s", argv
[0], "pass");
6473 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
6475 else if (strcmp (argv
[1], "r") == 0)
6477 if (!signal_print
[oursig
])
6478 sprintf (argBuf
, "%s %s", argv
[0], "print");
6480 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6486 handle_command (argBuf
, from_tty
);
6488 printf_filtered (_("Invalid signal handling flag.\n"));
6493 do_cleanups (old_chain
);
6497 gdb_signal_from_command (int num
)
6499 if (num
>= 1 && num
<= 15)
6500 return (enum gdb_signal
) num
;
6501 error (_("Only signals 1-15 are valid as numeric signals.\n\
6502 Use \"info signals\" for a list of symbolic signals."));
6505 /* Print current contents of the tables set by the handle command.
6506 It is possible we should just be printing signals actually used
6507 by the current target (but for things to work right when switching
6508 targets, all signals should be in the signal tables). */
6511 signals_info (char *signum_exp
, int from_tty
)
6513 enum gdb_signal oursig
;
6515 sig_print_header ();
6519 /* First see if this is a symbol name. */
6520 oursig
= gdb_signal_from_name (signum_exp
);
6521 if (oursig
== GDB_SIGNAL_UNKNOWN
)
6523 /* No, try numeric. */
6525 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
6527 sig_print_info (oursig
);
6531 printf_filtered ("\n");
6532 /* These ugly casts brought to you by the native VAX compiler. */
6533 for (oursig
= GDB_SIGNAL_FIRST
;
6534 (int) oursig
< (int) GDB_SIGNAL_LAST
;
6535 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
6539 if (oursig
!= GDB_SIGNAL_UNKNOWN
6540 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
6541 sig_print_info (oursig
);
6544 printf_filtered (_("\nUse the \"handle\" command "
6545 "to change these tables.\n"));
6548 /* Check if it makes sense to read $_siginfo from the current thread
6549 at this point. If not, throw an error. */
6552 validate_siginfo_access (void)
6554 /* No current inferior, no siginfo. */
6555 if (ptid_equal (inferior_ptid
, null_ptid
))
6556 error (_("No thread selected."));
6558 /* Don't try to read from a dead thread. */
6559 if (is_exited (inferior_ptid
))
6560 error (_("The current thread has terminated"));
6562 /* ... or from a spinning thread. */
6563 if (is_running (inferior_ptid
))
6564 error (_("Selected thread is running."));
6567 /* The $_siginfo convenience variable is a bit special. We don't know
6568 for sure the type of the value until we actually have a chance to
6569 fetch the data. The type can change depending on gdbarch, so it is
6570 also dependent on which thread you have selected.
6572 1. making $_siginfo be an internalvar that creates a new value on
6575 2. making the value of $_siginfo be an lval_computed value. */
6577 /* This function implements the lval_computed support for reading a
6581 siginfo_value_read (struct value
*v
)
6583 LONGEST transferred
;
6585 validate_siginfo_access ();
6588 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
6590 value_contents_all_raw (v
),
6592 TYPE_LENGTH (value_type (v
)));
6594 if (transferred
!= TYPE_LENGTH (value_type (v
)))
6595 error (_("Unable to read siginfo"));
6598 /* This function implements the lval_computed support for writing a
6602 siginfo_value_write (struct value
*v
, struct value
*fromval
)
6604 LONGEST transferred
;
6606 validate_siginfo_access ();
6608 transferred
= target_write (¤t_target
,
6609 TARGET_OBJECT_SIGNAL_INFO
,
6611 value_contents_all_raw (fromval
),
6613 TYPE_LENGTH (value_type (fromval
)));
6615 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
6616 error (_("Unable to write siginfo"));
6619 static const struct lval_funcs siginfo_value_funcs
=
6625 /* Return a new value with the correct type for the siginfo object of
6626 the current thread using architecture GDBARCH. Return a void value
6627 if there's no object available. */
6629 static struct value
*
6630 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
6633 if (target_has_stack
6634 && !ptid_equal (inferior_ptid
, null_ptid
)
6635 && gdbarch_get_siginfo_type_p (gdbarch
))
6637 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6639 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
6642 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
6646 /* infcall_suspend_state contains state about the program itself like its
6647 registers and any signal it received when it last stopped.
6648 This state must be restored regardless of how the inferior function call
6649 ends (either successfully, or after it hits a breakpoint or signal)
6650 if the program is to properly continue where it left off. */
6652 struct infcall_suspend_state
6654 struct thread_suspend_state thread_suspend
;
6655 struct inferior_suspend_state inferior_suspend
;
6659 struct regcache
*registers
;
6661 /* Format of SIGINFO_DATA or NULL if it is not present. */
6662 struct gdbarch
*siginfo_gdbarch
;
6664 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
6665 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
6666 content would be invalid. */
6667 gdb_byte
*siginfo_data
;
6670 struct infcall_suspend_state
*
6671 save_infcall_suspend_state (void)
6673 struct infcall_suspend_state
*inf_state
;
6674 struct thread_info
*tp
= inferior_thread ();
6675 struct inferior
*inf
= current_inferior ();
6676 struct regcache
*regcache
= get_current_regcache ();
6677 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6678 gdb_byte
*siginfo_data
= NULL
;
6680 if (gdbarch_get_siginfo_type_p (gdbarch
))
6682 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6683 size_t len
= TYPE_LENGTH (type
);
6684 struct cleanup
*back_to
;
6686 siginfo_data
= xmalloc (len
);
6687 back_to
= make_cleanup (xfree
, siginfo_data
);
6689 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6690 siginfo_data
, 0, len
) == len
)
6691 discard_cleanups (back_to
);
6694 /* Errors ignored. */
6695 do_cleanups (back_to
);
6696 siginfo_data
= NULL
;
6700 inf_state
= XZALLOC (struct infcall_suspend_state
);
6704 inf_state
->siginfo_gdbarch
= gdbarch
;
6705 inf_state
->siginfo_data
= siginfo_data
;
6708 inf_state
->thread_suspend
= tp
->suspend
;
6709 inf_state
->inferior_suspend
= inf
->suspend
;
6711 /* run_inferior_call will not use the signal due to its `proceed' call with
6712 GDB_SIGNAL_0 anyway. */
6713 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6715 inf_state
->stop_pc
= stop_pc
;
6717 inf_state
->registers
= regcache_dup (regcache
);
6722 /* Restore inferior session state to INF_STATE. */
6725 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6727 struct thread_info
*tp
= inferior_thread ();
6728 struct inferior
*inf
= current_inferior ();
6729 struct regcache
*regcache
= get_current_regcache ();
6730 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6732 tp
->suspend
= inf_state
->thread_suspend
;
6733 inf
->suspend
= inf_state
->inferior_suspend
;
6735 stop_pc
= inf_state
->stop_pc
;
6737 if (inf_state
->siginfo_gdbarch
== gdbarch
)
6739 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6740 size_t len
= TYPE_LENGTH (type
);
6742 /* Errors ignored. */
6743 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6744 inf_state
->siginfo_data
, 0, len
);
6747 /* The inferior can be gone if the user types "print exit(0)"
6748 (and perhaps other times). */
6749 if (target_has_execution
)
6750 /* NB: The register write goes through to the target. */
6751 regcache_cpy (regcache
, inf_state
->registers
);
6753 discard_infcall_suspend_state (inf_state
);
6757 do_restore_infcall_suspend_state_cleanup (void *state
)
6759 restore_infcall_suspend_state (state
);
6763 make_cleanup_restore_infcall_suspend_state
6764 (struct infcall_suspend_state
*inf_state
)
6766 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
6770 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6772 regcache_xfree (inf_state
->registers
);
6773 xfree (inf_state
->siginfo_data
);
6778 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
6780 return inf_state
->registers
;
6783 /* infcall_control_state contains state regarding gdb's control of the
6784 inferior itself like stepping control. It also contains session state like
6785 the user's currently selected frame. */
6787 struct infcall_control_state
6789 struct thread_control_state thread_control
;
6790 struct inferior_control_state inferior_control
;
6793 enum stop_stack_kind stop_stack_dummy
;
6794 int stopped_by_random_signal
;
6795 int stop_after_trap
;
6797 /* ID if the selected frame when the inferior function call was made. */
6798 struct frame_id selected_frame_id
;
6801 /* Save all of the information associated with the inferior<==>gdb
6804 struct infcall_control_state
*
6805 save_infcall_control_state (void)
6807 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
6808 struct thread_info
*tp
= inferior_thread ();
6809 struct inferior
*inf
= current_inferior ();
6811 inf_status
->thread_control
= tp
->control
;
6812 inf_status
->inferior_control
= inf
->control
;
6814 tp
->control
.step_resume_breakpoint
= NULL
;
6815 tp
->control
.exception_resume_breakpoint
= NULL
;
6817 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
6818 chain. If caller's caller is walking the chain, they'll be happier if we
6819 hand them back the original chain when restore_infcall_control_state is
6821 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
6824 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
6825 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
6826 inf_status
->stop_after_trap
= stop_after_trap
;
6828 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
6834 restore_selected_frame (void *args
)
6836 struct frame_id
*fid
= (struct frame_id
*) args
;
6837 struct frame_info
*frame
;
6839 frame
= frame_find_by_id (*fid
);
6841 /* If inf_status->selected_frame_id is NULL, there was no previously
6845 warning (_("Unable to restore previously selected frame."));
6849 select_frame (frame
);
6854 /* Restore inferior session state to INF_STATUS. */
6857 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
6859 struct thread_info
*tp
= inferior_thread ();
6860 struct inferior
*inf
= current_inferior ();
6862 if (tp
->control
.step_resume_breakpoint
)
6863 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
6865 if (tp
->control
.exception_resume_breakpoint
)
6866 tp
->control
.exception_resume_breakpoint
->disposition
6867 = disp_del_at_next_stop
;
6869 /* Handle the bpstat_copy of the chain. */
6870 bpstat_clear (&tp
->control
.stop_bpstat
);
6872 tp
->control
= inf_status
->thread_control
;
6873 inf
->control
= inf_status
->inferior_control
;
6876 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
6877 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
6878 stop_after_trap
= inf_status
->stop_after_trap
;
6880 if (target_has_stack
)
6882 /* The point of catch_errors is that if the stack is clobbered,
6883 walking the stack might encounter a garbage pointer and
6884 error() trying to dereference it. */
6886 (restore_selected_frame
, &inf_status
->selected_frame_id
,
6887 "Unable to restore previously selected frame:\n",
6888 RETURN_MASK_ERROR
) == 0)
6889 /* Error in restoring the selected frame. Select the innermost
6891 select_frame (get_current_frame ());
6898 do_restore_infcall_control_state_cleanup (void *sts
)
6900 restore_infcall_control_state (sts
);
6904 make_cleanup_restore_infcall_control_state
6905 (struct infcall_control_state
*inf_status
)
6907 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
6911 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
6913 if (inf_status
->thread_control
.step_resume_breakpoint
)
6914 inf_status
->thread_control
.step_resume_breakpoint
->disposition
6915 = disp_del_at_next_stop
;
6917 if (inf_status
->thread_control
.exception_resume_breakpoint
)
6918 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
6919 = disp_del_at_next_stop
;
6921 /* See save_infcall_control_state for info on stop_bpstat. */
6922 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
6928 ptid_match (ptid_t ptid
, ptid_t filter
)
6930 if (ptid_equal (filter
, minus_one_ptid
))
6932 if (ptid_is_pid (filter
)
6933 && ptid_get_pid (ptid
) == ptid_get_pid (filter
))
6935 else if (ptid_equal (ptid
, filter
))
6941 /* restore_inferior_ptid() will be used by the cleanup machinery
6942 to restore the inferior_ptid value saved in a call to
6943 save_inferior_ptid(). */
6946 restore_inferior_ptid (void *arg
)
6948 ptid_t
*saved_ptid_ptr
= arg
;
6950 inferior_ptid
= *saved_ptid_ptr
;
6954 /* Save the value of inferior_ptid so that it may be restored by a
6955 later call to do_cleanups(). Returns the struct cleanup pointer
6956 needed for later doing the cleanup. */
6959 save_inferior_ptid (void)
6961 ptid_t
*saved_ptid_ptr
;
6963 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
6964 *saved_ptid_ptr
= inferior_ptid
;
6965 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
6969 /* User interface for reverse debugging:
6970 Set exec-direction / show exec-direction commands
6971 (returns error unless target implements to_set_exec_direction method). */
6973 int execution_direction
= EXEC_FORWARD
;
6974 static const char exec_forward
[] = "forward";
6975 static const char exec_reverse
[] = "reverse";
6976 static const char *exec_direction
= exec_forward
;
6977 static const char *const exec_direction_names
[] = {
6984 set_exec_direction_func (char *args
, int from_tty
,
6985 struct cmd_list_element
*cmd
)
6987 if (target_can_execute_reverse
)
6989 if (!strcmp (exec_direction
, exec_forward
))
6990 execution_direction
= EXEC_FORWARD
;
6991 else if (!strcmp (exec_direction
, exec_reverse
))
6992 execution_direction
= EXEC_REVERSE
;
6996 exec_direction
= exec_forward
;
6997 error (_("Target does not support this operation."));
7002 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7003 struct cmd_list_element
*cmd
, const char *value
)
7005 switch (execution_direction
) {
7007 fprintf_filtered (out
, _("Forward.\n"));
7010 fprintf_filtered (out
, _("Reverse.\n"));
7013 internal_error (__FILE__
, __LINE__
,
7014 _("bogus execution_direction value: %d"),
7015 (int) execution_direction
);
7019 /* User interface for non-stop mode. */
7024 set_non_stop (char *args
, int from_tty
,
7025 struct cmd_list_element
*c
)
7027 if (target_has_execution
)
7029 non_stop_1
= non_stop
;
7030 error (_("Cannot change this setting while the inferior is running."));
7033 non_stop
= non_stop_1
;
7037 show_non_stop (struct ui_file
*file
, int from_tty
,
7038 struct cmd_list_element
*c
, const char *value
)
7040 fprintf_filtered (file
,
7041 _("Controlling the inferior in non-stop mode is %s.\n"),
7046 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7047 struct cmd_list_element
*c
, const char *value
)
7049 fprintf_filtered (file
, _("Resuming the execution of threads "
7050 "of all processes is %s.\n"), value
);
7053 /* Implementation of `siginfo' variable. */
7055 static const struct internalvar_funcs siginfo_funcs
=
7063 _initialize_infrun (void)
7068 add_info ("signals", signals_info
, _("\
7069 What debugger does when program gets various signals.\n\
7070 Specify a signal as argument to print info on that signal only."));
7071 add_info_alias ("handle", "signals", 0);
7073 add_com ("handle", class_run
, handle_command
, _("\
7074 Specify how to handle a signal.\n\
7075 Args are signals and actions to apply to those signals.\n\
7076 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7077 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7078 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7079 The special arg \"all\" is recognized to mean all signals except those\n\
7080 used by the debugger, typically SIGTRAP and SIGINT.\n\
7081 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7082 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7083 Stop means reenter debugger if this signal happens (implies print).\n\
7084 Print means print a message if this signal happens.\n\
7085 Pass means let program see this signal; otherwise program doesn't know.\n\
7086 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7087 Pass and Stop may be combined."));
7090 add_com ("lz", class_info
, signals_info
, _("\
7091 What debugger does when program gets various signals.\n\
7092 Specify a signal as argument to print info on that signal only."));
7093 add_com ("z", class_run
, xdb_handle_command
, _("\
7094 Specify how to handle a signal.\n\
7095 Args are signals and actions to apply to those signals.\n\
7096 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7097 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7098 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7099 The special arg \"all\" is recognized to mean all signals except those\n\
7100 used by the debugger, typically SIGTRAP and SIGINT.\n\
7101 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7102 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7103 nopass), \"Q\" (noprint)\n\
7104 Stop means reenter debugger if this signal happens (implies print).\n\
7105 Print means print a message if this signal happens.\n\
7106 Pass means let program see this signal; otherwise program doesn't know.\n\
7107 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7108 Pass and Stop may be combined."));
7112 stop_command
= add_cmd ("stop", class_obscure
,
7113 not_just_help_class_command
, _("\
7114 There is no `stop' command, but you can set a hook on `stop'.\n\
7115 This allows you to set a list of commands to be run each time execution\n\
7116 of the program stops."), &cmdlist
);
7118 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7119 Set inferior debugging."), _("\
7120 Show inferior debugging."), _("\
7121 When non-zero, inferior specific debugging is enabled."),
7124 &setdebuglist
, &showdebuglist
);
7126 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7127 &debug_displaced
, _("\
7128 Set displaced stepping debugging."), _("\
7129 Show displaced stepping debugging."), _("\
7130 When non-zero, displaced stepping specific debugging is enabled."),
7132 show_debug_displaced
,
7133 &setdebuglist
, &showdebuglist
);
7135 add_setshow_boolean_cmd ("non-stop", no_class
,
7137 Set whether gdb controls the inferior in non-stop mode."), _("\
7138 Show whether gdb controls the inferior in non-stop mode."), _("\
7139 When debugging a multi-threaded program and this setting is\n\
7140 off (the default, also called all-stop mode), when one thread stops\n\
7141 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7142 all other threads in the program while you interact with the thread of\n\
7143 interest. When you continue or step a thread, you can allow the other\n\
7144 threads to run, or have them remain stopped, but while you inspect any\n\
7145 thread's state, all threads stop.\n\
7147 In non-stop mode, when one thread stops, other threads can continue\n\
7148 to run freely. You'll be able to step each thread independently,\n\
7149 leave it stopped or free to run as needed."),
7155 numsigs
= (int) GDB_SIGNAL_LAST
;
7156 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7157 signal_print
= (unsigned char *)
7158 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7159 signal_program
= (unsigned char *)
7160 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7161 signal_pass
= (unsigned char *)
7162 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7163 for (i
= 0; i
< numsigs
; i
++)
7166 signal_print
[i
] = 1;
7167 signal_program
[i
] = 1;
7170 /* Signals caused by debugger's own actions
7171 should not be given to the program afterwards. */
7172 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7173 signal_program
[GDB_SIGNAL_INT
] = 0;
7175 /* Signals that are not errors should not normally enter the debugger. */
7176 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7177 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7178 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7179 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7180 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7181 signal_print
[GDB_SIGNAL_PROF
] = 0;
7182 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7183 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7184 signal_stop
[GDB_SIGNAL_IO
] = 0;
7185 signal_print
[GDB_SIGNAL_IO
] = 0;
7186 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7187 signal_print
[GDB_SIGNAL_POLL
] = 0;
7188 signal_stop
[GDB_SIGNAL_URG
] = 0;
7189 signal_print
[GDB_SIGNAL_URG
] = 0;
7190 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7191 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7192 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7193 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7195 /* These signals are used internally by user-level thread
7196 implementations. (See signal(5) on Solaris.) Like the above
7197 signals, a healthy program receives and handles them as part of
7198 its normal operation. */
7199 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7200 signal_print
[GDB_SIGNAL_LWP
] = 0;
7201 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7202 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7203 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7204 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7206 /* Update cached state. */
7207 signal_cache_update (-1);
7209 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7210 &stop_on_solib_events
, _("\
7211 Set stopping for shared library events."), _("\
7212 Show stopping for shared library events."), _("\
7213 If nonzero, gdb will give control to the user when the dynamic linker\n\
7214 notifies gdb of shared library events. The most common event of interest\n\
7215 to the user would be loading/unloading of a new library."),
7217 show_stop_on_solib_events
,
7218 &setlist
, &showlist
);
7220 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7221 follow_fork_mode_kind_names
,
7222 &follow_fork_mode_string
, _("\
7223 Set debugger response to a program call of fork or vfork."), _("\
7224 Show debugger response to a program call of fork or vfork."), _("\
7225 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7226 parent - the original process is debugged after a fork\n\
7227 child - the new process is debugged after a fork\n\
7228 The unfollowed process will continue to run.\n\
7229 By default, the debugger will follow the parent process."),
7231 show_follow_fork_mode_string
,
7232 &setlist
, &showlist
);
7234 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7235 follow_exec_mode_names
,
7236 &follow_exec_mode_string
, _("\
7237 Set debugger response to a program call of exec."), _("\
7238 Show debugger response to a program call of exec."), _("\
7239 An exec call replaces the program image of a process.\n\
7241 follow-exec-mode can be:\n\
7243 new - the debugger creates a new inferior and rebinds the process\n\
7244 to this new inferior. The program the process was running before\n\
7245 the exec call can be restarted afterwards by restarting the original\n\
7248 same - the debugger keeps the process bound to the same inferior.\n\
7249 The new executable image replaces the previous executable loaded in\n\
7250 the inferior. Restarting the inferior after the exec call restarts\n\
7251 the executable the process was running after the exec call.\n\
7253 By default, the debugger will use the same inferior."),
7255 show_follow_exec_mode_string
,
7256 &setlist
, &showlist
);
7258 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7259 scheduler_enums
, &scheduler_mode
, _("\
7260 Set mode for locking scheduler during execution."), _("\
7261 Show mode for locking scheduler during execution."), _("\
7262 off == no locking (threads may preempt at any time)\n\
7263 on == full locking (no thread except the current thread may run)\n\
7264 step == scheduler locked during every single-step operation.\n\
7265 In this mode, no other thread may run during a step command.\n\
7266 Other threads may run while stepping over a function call ('next')."),
7267 set_schedlock_func
, /* traps on target vector */
7268 show_scheduler_mode
,
7269 &setlist
, &showlist
);
7271 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7272 Set mode for resuming threads of all processes."), _("\
7273 Show mode for resuming threads of all processes."), _("\
7274 When on, execution commands (such as 'continue' or 'next') resume all\n\
7275 threads of all processes. When off (which is the default), execution\n\
7276 commands only resume the threads of the current process. The set of\n\
7277 threads that are resumed is further refined by the scheduler-locking\n\
7278 mode (see help set scheduler-locking)."),
7280 show_schedule_multiple
,
7281 &setlist
, &showlist
);
7283 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7284 Set mode of the step operation."), _("\
7285 Show mode of the step operation."), _("\
7286 When set, doing a step over a function without debug line information\n\
7287 will stop at the first instruction of that function. Otherwise, the\n\
7288 function is skipped and the step command stops at a different source line."),
7290 show_step_stop_if_no_debug
,
7291 &setlist
, &showlist
);
7293 add_setshow_enum_cmd ("displaced-stepping", class_run
,
7294 can_use_displaced_stepping_enum
,
7295 &can_use_displaced_stepping
, _("\
7296 Set debugger's willingness to use displaced stepping."), _("\
7297 Show debugger's willingness to use displaced stepping."), _("\
7298 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7299 supported by the target architecture. If off, gdb will not use displaced\n\
7300 stepping to step over breakpoints, even if such is supported by the target\n\
7301 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7302 if the target architecture supports it and non-stop mode is active, but will not\n\
7303 use it in all-stop mode (see help set non-stop)."),
7305 show_can_use_displaced_stepping
,
7306 &setlist
, &showlist
);
7308 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7309 &exec_direction
, _("Set direction of execution.\n\
7310 Options are 'forward' or 'reverse'."),
7311 _("Show direction of execution (forward/reverse)."),
7312 _("Tells gdb whether to execute forward or backward."),
7313 set_exec_direction_func
, show_exec_direction_func
,
7314 &setlist
, &showlist
);
7316 /* Set/show detach-on-fork: user-settable mode. */
7318 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7319 Set whether gdb will detach the child of a fork."), _("\
7320 Show whether gdb will detach the child of a fork."), _("\
7321 Tells gdb whether to detach the child of a fork."),
7322 NULL
, NULL
, &setlist
, &showlist
);
7324 /* Set/show disable address space randomization mode. */
7326 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7327 &disable_randomization
, _("\
7328 Set disabling of debuggee's virtual address space randomization."), _("\
7329 Show disabling of debuggee's virtual address space randomization."), _("\
7330 When this mode is on (which is the default), randomization of the virtual\n\
7331 address space is disabled. Standalone programs run with the randomization\n\
7332 enabled by default on some platforms."),
7333 &set_disable_randomization
,
7334 &show_disable_randomization
,
7335 &setlist
, &showlist
);
7337 /* ptid initializations */
7338 inferior_ptid
= null_ptid
;
7339 target_last_wait_ptid
= minus_one_ptid
;
7341 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7342 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7343 observer_attach_thread_exit (infrun_thread_thread_exit
);
7344 observer_attach_inferior_exit (infrun_inferior_exit
);
7346 /* Explicitly create without lookup, since that tries to create a
7347 value with a void typed value, and when we get here, gdbarch
7348 isn't initialized yet. At this point, we're quite sure there
7349 isn't another convenience variable of the same name. */
7350 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7352 add_setshow_boolean_cmd ("observer", no_class
,
7353 &observer_mode_1
, _("\
7354 Set whether gdb controls the inferior in observer mode."), _("\
7355 Show whether gdb controls the inferior in observer mode."), _("\
7356 In observer mode, GDB can get data from the inferior, but not\n\
7357 affect its execution. Registers and memory may not be changed,\n\
7358 breakpoints may not be set, and the program cannot be interrupted\n\