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 /* If ON, and the architecture supports it, GDB will use displaced
1189 stepping to step over breakpoints. If OFF, or if the architecture
1190 doesn't support it, GDB will instead use the traditional
1191 hold-and-step approach. If AUTO (which is the default), GDB will
1192 decide which technique to use to step over breakpoints depending on
1193 which of all-stop or non-stop mode is active --- displaced stepping
1194 in non-stop mode; hold-and-step in all-stop mode. */
1196 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1199 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1200 struct cmd_list_element
*c
,
1203 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1204 fprintf_filtered (file
,
1205 _("Debugger's willingness to use displaced stepping "
1206 "to step over breakpoints is %s (currently %s).\n"),
1207 value
, non_stop
? "on" : "off");
1209 fprintf_filtered (file
,
1210 _("Debugger's willingness to use displaced stepping "
1211 "to step over breakpoints is %s.\n"), value
);
1214 /* Return non-zero if displaced stepping can/should be used to step
1215 over breakpoints. */
1218 use_displaced_stepping (struct gdbarch
*gdbarch
)
1220 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
&& non_stop
)
1221 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1222 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1223 && !RECORD_IS_USED
);
1226 /* Clean out any stray displaced stepping state. */
1228 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1230 /* Indicate that there is no cleanup pending. */
1231 displaced
->step_ptid
= null_ptid
;
1233 if (displaced
->step_closure
)
1235 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1236 displaced
->step_closure
);
1237 displaced
->step_closure
= NULL
;
1242 displaced_step_clear_cleanup (void *arg
)
1244 struct displaced_step_inferior_state
*state
= arg
;
1246 displaced_step_clear (state
);
1249 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1251 displaced_step_dump_bytes (struct ui_file
*file
,
1252 const gdb_byte
*buf
,
1257 for (i
= 0; i
< len
; i
++)
1258 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1259 fputs_unfiltered ("\n", file
);
1262 /* Prepare to single-step, using displaced stepping.
1264 Note that we cannot use displaced stepping when we have a signal to
1265 deliver. If we have a signal to deliver and an instruction to step
1266 over, then after the step, there will be no indication from the
1267 target whether the thread entered a signal handler or ignored the
1268 signal and stepped over the instruction successfully --- both cases
1269 result in a simple SIGTRAP. In the first case we mustn't do a
1270 fixup, and in the second case we must --- but we can't tell which.
1271 Comments in the code for 'random signals' in handle_inferior_event
1272 explain how we handle this case instead.
1274 Returns 1 if preparing was successful -- this thread is going to be
1275 stepped now; or 0 if displaced stepping this thread got queued. */
1277 displaced_step_prepare (ptid_t ptid
)
1279 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1280 struct regcache
*regcache
= get_thread_regcache (ptid
);
1281 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1282 CORE_ADDR original
, copy
;
1284 struct displaced_step_closure
*closure
;
1285 struct displaced_step_inferior_state
*displaced
;
1288 /* We should never reach this function if the architecture does not
1289 support displaced stepping. */
1290 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1292 /* We have to displaced step one thread at a time, as we only have
1293 access to a single scratch space per inferior. */
1295 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1297 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1299 /* Already waiting for a displaced step to finish. Defer this
1300 request and place in queue. */
1301 struct displaced_step_request
*req
, *new_req
;
1303 if (debug_displaced
)
1304 fprintf_unfiltered (gdb_stdlog
,
1305 "displaced: defering step of %s\n",
1306 target_pid_to_str (ptid
));
1308 new_req
= xmalloc (sizeof (*new_req
));
1309 new_req
->ptid
= ptid
;
1310 new_req
->next
= NULL
;
1312 if (displaced
->step_request_queue
)
1314 for (req
= displaced
->step_request_queue
;
1318 req
->next
= new_req
;
1321 displaced
->step_request_queue
= new_req
;
1327 if (debug_displaced
)
1328 fprintf_unfiltered (gdb_stdlog
,
1329 "displaced: stepping %s now\n",
1330 target_pid_to_str (ptid
));
1333 displaced_step_clear (displaced
);
1335 old_cleanups
= save_inferior_ptid ();
1336 inferior_ptid
= ptid
;
1338 original
= regcache_read_pc (regcache
);
1340 copy
= gdbarch_displaced_step_location (gdbarch
);
1341 len
= gdbarch_max_insn_length (gdbarch
);
1343 /* Save the original contents of the copy area. */
1344 displaced
->step_saved_copy
= xmalloc (len
);
1345 ignore_cleanups
= make_cleanup (free_current_contents
,
1346 &displaced
->step_saved_copy
);
1347 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1349 throw_error (MEMORY_ERROR
,
1350 _("Error accessing memory address %s (%s) for "
1351 "displaced-stepping scratch space."),
1352 paddress (gdbarch
, copy
), safe_strerror (status
));
1353 if (debug_displaced
)
1355 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1356 paddress (gdbarch
, copy
));
1357 displaced_step_dump_bytes (gdb_stdlog
,
1358 displaced
->step_saved_copy
,
1362 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1363 original
, copy
, regcache
);
1365 /* We don't support the fully-simulated case at present. */
1366 gdb_assert (closure
);
1368 /* Save the information we need to fix things up if the step
1370 displaced
->step_ptid
= ptid
;
1371 displaced
->step_gdbarch
= gdbarch
;
1372 displaced
->step_closure
= closure
;
1373 displaced
->step_original
= original
;
1374 displaced
->step_copy
= copy
;
1376 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1378 /* Resume execution at the copy. */
1379 regcache_write_pc (regcache
, copy
);
1381 discard_cleanups (ignore_cleanups
);
1383 do_cleanups (old_cleanups
);
1385 if (debug_displaced
)
1386 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1387 paddress (gdbarch
, copy
));
1393 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1394 const gdb_byte
*myaddr
, int len
)
1396 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1398 inferior_ptid
= ptid
;
1399 write_memory (memaddr
, myaddr
, len
);
1400 do_cleanups (ptid_cleanup
);
1403 /* Restore the contents of the copy area for thread PTID. */
1406 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1409 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1411 write_memory_ptid (ptid
, displaced
->step_copy
,
1412 displaced
->step_saved_copy
, len
);
1413 if (debug_displaced
)
1414 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1415 target_pid_to_str (ptid
),
1416 paddress (displaced
->step_gdbarch
,
1417 displaced
->step_copy
));
1421 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1423 struct cleanup
*old_cleanups
;
1424 struct displaced_step_inferior_state
*displaced
1425 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1427 /* Was any thread of this process doing a displaced step? */
1428 if (displaced
== NULL
)
1431 /* Was this event for the pid we displaced? */
1432 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1433 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1436 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1438 displaced_step_restore (displaced
, displaced
->step_ptid
);
1440 /* Did the instruction complete successfully? */
1441 if (signal
== GDB_SIGNAL_TRAP
)
1443 /* Fix up the resulting state. */
1444 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1445 displaced
->step_closure
,
1446 displaced
->step_original
,
1447 displaced
->step_copy
,
1448 get_thread_regcache (displaced
->step_ptid
));
1452 /* Since the instruction didn't complete, all we can do is
1454 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1455 CORE_ADDR pc
= regcache_read_pc (regcache
);
1457 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1458 regcache_write_pc (regcache
, pc
);
1461 do_cleanups (old_cleanups
);
1463 displaced
->step_ptid
= null_ptid
;
1465 /* Are there any pending displaced stepping requests? If so, run
1466 one now. Leave the state object around, since we're likely to
1467 need it again soon. */
1468 while (displaced
->step_request_queue
)
1470 struct displaced_step_request
*head
;
1472 struct regcache
*regcache
;
1473 struct gdbarch
*gdbarch
;
1474 CORE_ADDR actual_pc
;
1475 struct address_space
*aspace
;
1477 head
= displaced
->step_request_queue
;
1479 displaced
->step_request_queue
= head
->next
;
1482 context_switch (ptid
);
1484 regcache
= get_thread_regcache (ptid
);
1485 actual_pc
= regcache_read_pc (regcache
);
1486 aspace
= get_regcache_aspace (regcache
);
1488 if (breakpoint_here_p (aspace
, actual_pc
))
1490 if (debug_displaced
)
1491 fprintf_unfiltered (gdb_stdlog
,
1492 "displaced: stepping queued %s now\n",
1493 target_pid_to_str (ptid
));
1495 displaced_step_prepare (ptid
);
1497 gdbarch
= get_regcache_arch (regcache
);
1499 if (debug_displaced
)
1501 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
1504 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1505 paddress (gdbarch
, actual_pc
));
1506 read_memory (actual_pc
, buf
, sizeof (buf
));
1507 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1510 if (gdbarch_displaced_step_hw_singlestep (gdbarch
,
1511 displaced
->step_closure
))
1512 target_resume (ptid
, 1, GDB_SIGNAL_0
);
1514 target_resume (ptid
, 0, GDB_SIGNAL_0
);
1516 /* Done, we're stepping a thread. */
1522 struct thread_info
*tp
= inferior_thread ();
1524 /* The breakpoint we were sitting under has since been
1526 tp
->control
.trap_expected
= 0;
1528 /* Go back to what we were trying to do. */
1529 step
= currently_stepping (tp
);
1531 if (debug_displaced
)
1532 fprintf_unfiltered (gdb_stdlog
,
1533 "displaced: breakpoint is gone: %s, step(%d)\n",
1534 target_pid_to_str (tp
->ptid
), step
);
1536 target_resume (ptid
, step
, GDB_SIGNAL_0
);
1537 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1539 /* This request was discarded. See if there's any other
1540 thread waiting for its turn. */
1545 /* Update global variables holding ptids to hold NEW_PTID if they were
1546 holding OLD_PTID. */
1548 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1550 struct displaced_step_request
*it
;
1551 struct displaced_step_inferior_state
*displaced
;
1553 if (ptid_equal (inferior_ptid
, old_ptid
))
1554 inferior_ptid
= new_ptid
;
1556 if (ptid_equal (singlestep_ptid
, old_ptid
))
1557 singlestep_ptid
= new_ptid
;
1559 if (ptid_equal (deferred_step_ptid
, old_ptid
))
1560 deferred_step_ptid
= new_ptid
;
1562 for (displaced
= displaced_step_inferior_states
;
1564 displaced
= displaced
->next
)
1566 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
1567 displaced
->step_ptid
= new_ptid
;
1569 for (it
= displaced
->step_request_queue
; it
; it
= it
->next
)
1570 if (ptid_equal (it
->ptid
, old_ptid
))
1571 it
->ptid
= new_ptid
;
1578 /* Things to clean up if we QUIT out of resume (). */
1580 resume_cleanups (void *ignore
)
1585 static const char schedlock_off
[] = "off";
1586 static const char schedlock_on
[] = "on";
1587 static const char schedlock_step
[] = "step";
1588 static const char *const scheduler_enums
[] = {
1594 static const char *scheduler_mode
= schedlock_off
;
1596 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1597 struct cmd_list_element
*c
, const char *value
)
1599 fprintf_filtered (file
,
1600 _("Mode for locking scheduler "
1601 "during execution is \"%s\".\n"),
1606 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1608 if (!target_can_lock_scheduler
)
1610 scheduler_mode
= schedlock_off
;
1611 error (_("Target '%s' cannot support this command."), target_shortname
);
1615 /* True if execution commands resume all threads of all processes by
1616 default; otherwise, resume only threads of the current inferior
1618 int sched_multi
= 0;
1620 /* Try to setup for software single stepping over the specified location.
1621 Return 1 if target_resume() should use hardware single step.
1623 GDBARCH the current gdbarch.
1624 PC the location to step over. */
1627 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1631 if (execution_direction
== EXEC_FORWARD
1632 && gdbarch_software_single_step_p (gdbarch
)
1633 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1636 /* Do not pull these breakpoints until after a `wait' in
1637 `wait_for_inferior'. */
1638 singlestep_breakpoints_inserted_p
= 1;
1639 singlestep_ptid
= inferior_ptid
;
1645 /* Return a ptid representing the set of threads that we will proceed,
1646 in the perspective of the user/frontend. We may actually resume
1647 fewer threads at first, e.g., if a thread is stopped at a
1648 breakpoint that needs stepping-off, but that should not be visible
1649 to the user/frontend, and neither should the frontend/user be
1650 allowed to proceed any of the threads that happen to be stopped for
1651 internal run control handling, if a previous command wanted them
1655 user_visible_resume_ptid (int step
)
1657 /* By default, resume all threads of all processes. */
1658 ptid_t resume_ptid
= RESUME_ALL
;
1660 /* Maybe resume only all threads of the current process. */
1661 if (!sched_multi
&& target_supports_multi_process ())
1663 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
1666 /* Maybe resume a single thread after all. */
1669 /* With non-stop mode on, threads are always handled
1671 resume_ptid
= inferior_ptid
;
1673 else if ((scheduler_mode
== schedlock_on
)
1674 || (scheduler_mode
== schedlock_step
1675 && (step
|| singlestep_breakpoints_inserted_p
)))
1677 /* User-settable 'scheduler' mode requires solo thread resume. */
1678 resume_ptid
= inferior_ptid
;
1684 /* Resume the inferior, but allow a QUIT. This is useful if the user
1685 wants to interrupt some lengthy single-stepping operation
1686 (for child processes, the SIGINT goes to the inferior, and so
1687 we get a SIGINT random_signal, but for remote debugging and perhaps
1688 other targets, that's not true).
1690 STEP nonzero if we should step (zero to continue instead).
1691 SIG is the signal to give the inferior (zero for none). */
1693 resume (int step
, enum gdb_signal sig
)
1695 int should_resume
= 1;
1696 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
1697 struct regcache
*regcache
= get_current_regcache ();
1698 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1699 struct thread_info
*tp
= inferior_thread ();
1700 CORE_ADDR pc
= regcache_read_pc (regcache
);
1701 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1705 if (current_inferior ()->waiting_for_vfork_done
)
1707 /* Don't try to single-step a vfork parent that is waiting for
1708 the child to get out of the shared memory region (by exec'ing
1709 or exiting). This is particularly important on software
1710 single-step archs, as the child process would trip on the
1711 software single step breakpoint inserted for the parent
1712 process. Since the parent will not actually execute any
1713 instruction until the child is out of the shared region (such
1714 are vfork's semantics), it is safe to simply continue it.
1715 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
1716 the parent, and tell it to `keep_going', which automatically
1717 re-sets it stepping. */
1719 fprintf_unfiltered (gdb_stdlog
,
1720 "infrun: resume : clear step\n");
1725 fprintf_unfiltered (gdb_stdlog
,
1726 "infrun: resume (step=%d, signal=%d), "
1727 "trap_expected=%d, current thread [%s] at %s\n",
1728 step
, sig
, tp
->control
.trap_expected
,
1729 target_pid_to_str (inferior_ptid
),
1730 paddress (gdbarch
, pc
));
1732 /* Normally, by the time we reach `resume', the breakpoints are either
1733 removed or inserted, as appropriate. The exception is if we're sitting
1734 at a permanent breakpoint; we need to step over it, but permanent
1735 breakpoints can't be removed. So we have to test for it here. */
1736 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
1738 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
1739 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
1742 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1743 how to step past a permanent breakpoint on this architecture. Try using\n\
1744 a command like `return' or `jump' to continue execution."));
1747 /* If enabled, step over breakpoints by executing a copy of the
1748 instruction at a different address.
1750 We can't use displaced stepping when we have a signal to deliver;
1751 the comments for displaced_step_prepare explain why. The
1752 comments in the handle_inferior event for dealing with 'random
1753 signals' explain what we do instead.
1755 We can't use displaced stepping when we are waiting for vfork_done
1756 event, displaced stepping breaks the vfork child similarly as single
1757 step software breakpoint. */
1758 if (use_displaced_stepping (gdbarch
)
1759 && (tp
->control
.trap_expected
1760 || (step
&& gdbarch_software_single_step_p (gdbarch
)))
1761 && sig
== GDB_SIGNAL_0
1762 && !current_inferior ()->waiting_for_vfork_done
)
1764 struct displaced_step_inferior_state
*displaced
;
1766 if (!displaced_step_prepare (inferior_ptid
))
1768 /* Got placed in displaced stepping queue. Will be resumed
1769 later when all the currently queued displaced stepping
1770 requests finish. The thread is not executing at this point,
1771 and the call to set_executing will be made later. But we
1772 need to call set_running here, since from frontend point of view,
1773 the thread is running. */
1774 set_running (inferior_ptid
, 1);
1775 discard_cleanups (old_cleanups
);
1779 /* Update pc to reflect the new address from which we will execute
1780 instructions due to displaced stepping. */
1781 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
1783 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1784 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
1785 displaced
->step_closure
);
1788 /* Do we need to do it the hard way, w/temp breakpoints? */
1790 step
= maybe_software_singlestep (gdbarch
, pc
);
1792 /* Currently, our software single-step implementation leads to different
1793 results than hardware single-stepping in one situation: when stepping
1794 into delivering a signal which has an associated signal handler,
1795 hardware single-step will stop at the first instruction of the handler,
1796 while software single-step will simply skip execution of the handler.
1798 For now, this difference in behavior is accepted since there is no
1799 easy way to actually implement single-stepping into a signal handler
1800 without kernel support.
1802 However, there is one scenario where this difference leads to follow-on
1803 problems: if we're stepping off a breakpoint by removing all breakpoints
1804 and then single-stepping. In this case, the software single-step
1805 behavior means that even if there is a *breakpoint* in the signal
1806 handler, GDB still would not stop.
1808 Fortunately, we can at least fix this particular issue. We detect
1809 here the case where we are about to deliver a signal while software
1810 single-stepping with breakpoints removed. In this situation, we
1811 revert the decisions to remove all breakpoints and insert single-
1812 step breakpoints, and instead we install a step-resume breakpoint
1813 at the current address, deliver the signal without stepping, and
1814 once we arrive back at the step-resume breakpoint, actually step
1815 over the breakpoint we originally wanted to step over. */
1816 if (singlestep_breakpoints_inserted_p
1817 && tp
->control
.trap_expected
&& sig
!= GDB_SIGNAL_0
)
1819 /* If we have nested signals or a pending signal is delivered
1820 immediately after a handler returns, might might already have
1821 a step-resume breakpoint set on the earlier handler. We cannot
1822 set another step-resume breakpoint; just continue on until the
1823 original breakpoint is hit. */
1824 if (tp
->control
.step_resume_breakpoint
== NULL
)
1826 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
1827 tp
->step_after_step_resume_breakpoint
= 1;
1830 remove_single_step_breakpoints ();
1831 singlestep_breakpoints_inserted_p
= 0;
1833 insert_breakpoints ();
1834 tp
->control
.trap_expected
= 0;
1841 /* If STEP is set, it's a request to use hardware stepping
1842 facilities. But in that case, we should never
1843 use singlestep breakpoint. */
1844 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1846 /* Decide the set of threads to ask the target to resume. Start
1847 by assuming everything will be resumed, than narrow the set
1848 by applying increasingly restricting conditions. */
1849 resume_ptid
= user_visible_resume_ptid (step
);
1851 /* Maybe resume a single thread after all. */
1852 if (singlestep_breakpoints_inserted_p
1853 && stepping_past_singlestep_breakpoint
)
1855 /* The situation here is as follows. In thread T1 we wanted to
1856 single-step. Lacking hardware single-stepping we've
1857 set breakpoint at the PC of the next instruction -- call it
1858 P. After resuming, we've hit that breakpoint in thread T2.
1859 Now we've removed original breakpoint, inserted breakpoint
1860 at P+1, and try to step to advance T2 past breakpoint.
1861 We need to step only T2, as if T1 is allowed to freely run,
1862 it can run past P, and if other threads are allowed to run,
1863 they can hit breakpoint at P+1, and nested hits of single-step
1864 breakpoints is not something we'd want -- that's complicated
1865 to support, and has no value. */
1866 resume_ptid
= inferior_ptid
;
1868 else if ((step
|| singlestep_breakpoints_inserted_p
)
1869 && tp
->control
.trap_expected
)
1871 /* We're allowing a thread to run past a breakpoint it has
1872 hit, by single-stepping the thread with the breakpoint
1873 removed. In which case, we need to single-step only this
1874 thread, and keep others stopped, as they can miss this
1875 breakpoint if allowed to run.
1877 The current code actually removes all breakpoints when
1878 doing this, not just the one being stepped over, so if we
1879 let other threads run, we can actually miss any
1880 breakpoint, not just the one at PC. */
1881 resume_ptid
= inferior_ptid
;
1884 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1886 /* Most targets can step a breakpoint instruction, thus
1887 executing it normally. But if this one cannot, just
1888 continue and we will hit it anyway. */
1889 if (step
&& breakpoint_inserted_here_p (aspace
, pc
))
1894 && use_displaced_stepping (gdbarch
)
1895 && tp
->control
.trap_expected
)
1897 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1898 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
1899 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1902 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1903 paddress (resume_gdbarch
, actual_pc
));
1904 read_memory (actual_pc
, buf
, sizeof (buf
));
1905 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1908 /* Install inferior's terminal modes. */
1909 target_terminal_inferior ();
1911 /* Avoid confusing the next resume, if the next stop/resume
1912 happens to apply to another thread. */
1913 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1915 /* Advise target which signals may be handled silently. If we have
1916 removed breakpoints because we are stepping over one (which can
1917 happen only if we are not using displaced stepping), we need to
1918 receive all signals to avoid accidentally skipping a breakpoint
1919 during execution of a signal handler. */
1920 if ((step
|| singlestep_breakpoints_inserted_p
)
1921 && tp
->control
.trap_expected
1922 && !use_displaced_stepping (gdbarch
))
1923 target_pass_signals (0, NULL
);
1925 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
1927 target_resume (resume_ptid
, step
, sig
);
1930 discard_cleanups (old_cleanups
);
1935 /* Clear out all variables saying what to do when inferior is continued.
1936 First do this, then set the ones you want, then call `proceed'. */
1939 clear_proceed_status_thread (struct thread_info
*tp
)
1942 fprintf_unfiltered (gdb_stdlog
,
1943 "infrun: clear_proceed_status_thread (%s)\n",
1944 target_pid_to_str (tp
->ptid
));
1946 tp
->control
.trap_expected
= 0;
1947 tp
->control
.step_range_start
= 0;
1948 tp
->control
.step_range_end
= 0;
1949 tp
->control
.step_frame_id
= null_frame_id
;
1950 tp
->control
.step_stack_frame_id
= null_frame_id
;
1951 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1952 tp
->stop_requested
= 0;
1954 tp
->control
.stop_step
= 0;
1956 tp
->control
.proceed_to_finish
= 0;
1958 /* Discard any remaining commands or status from previous stop. */
1959 bpstat_clear (&tp
->control
.stop_bpstat
);
1963 clear_proceed_status_callback (struct thread_info
*tp
, void *data
)
1965 if (is_exited (tp
->ptid
))
1968 clear_proceed_status_thread (tp
);
1973 clear_proceed_status (void)
1977 /* In all-stop mode, delete the per-thread status of all
1978 threads, even if inferior_ptid is null_ptid, there may be
1979 threads on the list. E.g., we may be launching a new
1980 process, while selecting the executable. */
1981 iterate_over_threads (clear_proceed_status_callback
, NULL
);
1984 if (!ptid_equal (inferior_ptid
, null_ptid
))
1986 struct inferior
*inferior
;
1990 /* If in non-stop mode, only delete the per-thread status of
1991 the current thread. */
1992 clear_proceed_status_thread (inferior_thread ());
1995 inferior
= current_inferior ();
1996 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
1999 stop_after_trap
= 0;
2001 observer_notify_about_to_proceed ();
2005 regcache_xfree (stop_registers
);
2006 stop_registers
= NULL
;
2010 /* Check the current thread against the thread that reported the most recent
2011 event. If a step-over is required return TRUE and set the current thread
2012 to the old thread. Otherwise return FALSE.
2014 This should be suitable for any targets that support threads. */
2017 prepare_to_proceed (int step
)
2020 struct target_waitstatus wait_status
;
2021 int schedlock_enabled
;
2023 /* With non-stop mode on, threads are always handled individually. */
2024 gdb_assert (! non_stop
);
2026 /* Get the last target status returned by target_wait(). */
2027 get_last_target_status (&wait_ptid
, &wait_status
);
2029 /* Make sure we were stopped at a breakpoint. */
2030 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
2031 || (wait_status
.value
.sig
!= GDB_SIGNAL_TRAP
2032 && wait_status
.value
.sig
!= GDB_SIGNAL_ILL
2033 && wait_status
.value
.sig
!= GDB_SIGNAL_SEGV
2034 && wait_status
.value
.sig
!= GDB_SIGNAL_EMT
))
2039 schedlock_enabled
= (scheduler_mode
== schedlock_on
2040 || (scheduler_mode
== schedlock_step
2043 /* Don't switch over to WAIT_PTID if scheduler locking is on. */
2044 if (schedlock_enabled
)
2047 /* Don't switch over if we're about to resume some other process
2048 other than WAIT_PTID's, and schedule-multiple is off. */
2050 && ptid_get_pid (wait_ptid
) != ptid_get_pid (inferior_ptid
))
2053 /* Switched over from WAIT_PID. */
2054 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
2055 && !ptid_equal (inferior_ptid
, wait_ptid
))
2057 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
2059 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2060 regcache_read_pc (regcache
)))
2062 /* If stepping, remember current thread to switch back to. */
2064 deferred_step_ptid
= inferior_ptid
;
2066 /* Switch back to WAIT_PID thread. */
2067 switch_to_thread (wait_ptid
);
2070 fprintf_unfiltered (gdb_stdlog
,
2071 "infrun: prepare_to_proceed (step=%d), "
2072 "switched to [%s]\n",
2073 step
, target_pid_to_str (inferior_ptid
));
2075 /* We return 1 to indicate that there is a breakpoint here,
2076 so we need to step over it before continuing to avoid
2077 hitting it straight away. */
2085 /* Basic routine for continuing the program in various fashions.
2087 ADDR is the address to resume at, or -1 for resume where stopped.
2088 SIGGNAL is the signal to give it, or 0 for none,
2089 or -1 for act according to how it stopped.
2090 STEP is nonzero if should trap after one instruction.
2091 -1 means return after that and print nothing.
2092 You should probably set various step_... variables
2093 before calling here, if you are stepping.
2095 You should call clear_proceed_status before calling proceed. */
2098 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
, int step
)
2100 struct regcache
*regcache
;
2101 struct gdbarch
*gdbarch
;
2102 struct thread_info
*tp
;
2104 struct address_space
*aspace
;
2107 /* If we're stopped at a fork/vfork, follow the branch set by the
2108 "set follow-fork-mode" command; otherwise, we'll just proceed
2109 resuming the current thread. */
2110 if (!follow_fork ())
2112 /* The target for some reason decided not to resume. */
2114 if (target_can_async_p ())
2115 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2119 /* We'll update this if & when we switch to a new thread. */
2120 previous_inferior_ptid
= inferior_ptid
;
2122 regcache
= get_current_regcache ();
2123 gdbarch
= get_regcache_arch (regcache
);
2124 aspace
= get_regcache_aspace (regcache
);
2125 pc
= regcache_read_pc (regcache
);
2128 step_start_function
= find_pc_function (pc
);
2130 stop_after_trap
= 1;
2132 if (addr
== (CORE_ADDR
) -1)
2134 if (pc
== stop_pc
&& breakpoint_here_p (aspace
, pc
)
2135 && execution_direction
!= EXEC_REVERSE
)
2136 /* There is a breakpoint at the address we will resume at,
2137 step one instruction before inserting breakpoints so that
2138 we do not stop right away (and report a second hit at this
2141 Note, we don't do this in reverse, because we won't
2142 actually be executing the breakpoint insn anyway.
2143 We'll be (un-)executing the previous instruction. */
2146 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2147 && gdbarch_single_step_through_delay (gdbarch
,
2148 get_current_frame ()))
2149 /* We stepped onto an instruction that needs to be stepped
2150 again before re-inserting the breakpoint, do so. */
2155 regcache_write_pc (regcache
, addr
);
2159 fprintf_unfiltered (gdb_stdlog
,
2160 "infrun: proceed (addr=%s, signal=%d, step=%d)\n",
2161 paddress (gdbarch
, addr
), siggnal
, step
);
2164 /* In non-stop, each thread is handled individually. The context
2165 must already be set to the right thread here. */
2169 /* In a multi-threaded task we may select another thread and
2170 then continue or step.
2172 But if the old thread was stopped at a breakpoint, it will
2173 immediately cause another breakpoint stop without any
2174 execution (i.e. it will report a breakpoint hit incorrectly).
2175 So we must step over it first.
2177 prepare_to_proceed checks the current thread against the
2178 thread that reported the most recent event. If a step-over
2179 is required it returns TRUE and sets the current thread to
2181 if (prepare_to_proceed (step
))
2185 /* prepare_to_proceed may change the current thread. */
2186 tp
= inferior_thread ();
2190 tp
->control
.trap_expected
= 1;
2191 /* If displaced stepping is enabled, we can step over the
2192 breakpoint without hitting it, so leave all breakpoints
2193 inserted. Otherwise we need to disable all breakpoints, step
2194 one instruction, and then re-add them when that step is
2196 if (!use_displaced_stepping (gdbarch
))
2197 remove_breakpoints ();
2200 /* We can insert breakpoints if we're not trying to step over one,
2201 or if we are stepping over one but we're using displaced stepping
2203 if (! tp
->control
.trap_expected
|| use_displaced_stepping (gdbarch
))
2204 insert_breakpoints ();
2208 /* Pass the last stop signal to the thread we're resuming,
2209 irrespective of whether the current thread is the thread that
2210 got the last event or not. This was historically GDB's
2211 behaviour before keeping a stop_signal per thread. */
2213 struct thread_info
*last_thread
;
2215 struct target_waitstatus last_status
;
2217 get_last_target_status (&last_ptid
, &last_status
);
2218 if (!ptid_equal (inferior_ptid
, last_ptid
)
2219 && !ptid_equal (last_ptid
, null_ptid
)
2220 && !ptid_equal (last_ptid
, minus_one_ptid
))
2222 last_thread
= find_thread_ptid (last_ptid
);
2225 tp
->suspend
.stop_signal
= last_thread
->suspend
.stop_signal
;
2226 last_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2231 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2232 tp
->suspend
.stop_signal
= siggnal
;
2233 /* If this signal should not be seen by program,
2234 give it zero. Used for debugging signals. */
2235 else if (!signal_program
[tp
->suspend
.stop_signal
])
2236 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2238 annotate_starting ();
2240 /* Make sure that output from GDB appears before output from the
2242 gdb_flush (gdb_stdout
);
2244 /* Refresh prev_pc value just prior to resuming. This used to be
2245 done in stop_stepping, however, setting prev_pc there did not handle
2246 scenarios such as inferior function calls or returning from
2247 a function via the return command. In those cases, the prev_pc
2248 value was not set properly for subsequent commands. The prev_pc value
2249 is used to initialize the starting line number in the ecs. With an
2250 invalid value, the gdb next command ends up stopping at the position
2251 represented by the next line table entry past our start position.
2252 On platforms that generate one line table entry per line, this
2253 is not a problem. However, on the ia64, the compiler generates
2254 extraneous line table entries that do not increase the line number.
2255 When we issue the gdb next command on the ia64 after an inferior call
2256 or a return command, we often end up a few instructions forward, still
2257 within the original line we started.
2259 An attempt was made to refresh the prev_pc at the same time the
2260 execution_control_state is initialized (for instance, just before
2261 waiting for an inferior event). But this approach did not work
2262 because of platforms that use ptrace, where the pc register cannot
2263 be read unless the inferior is stopped. At that point, we are not
2264 guaranteed the inferior is stopped and so the regcache_read_pc() call
2265 can fail. Setting the prev_pc value here ensures the value is updated
2266 correctly when the inferior is stopped. */
2267 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2269 /* Fill in with reasonable starting values. */
2270 init_thread_stepping_state (tp
);
2272 /* Reset to normal state. */
2273 init_infwait_state ();
2275 /* Resume inferior. */
2276 resume (oneproc
|| step
|| bpstat_should_step (), tp
->suspend
.stop_signal
);
2278 /* Wait for it to stop (if not standalone)
2279 and in any case decode why it stopped, and act accordingly. */
2280 /* Do this only if we are not using the event loop, or if the target
2281 does not support asynchronous execution. */
2282 if (!target_can_async_p ())
2284 wait_for_inferior ();
2290 /* Start remote-debugging of a machine over a serial link. */
2293 start_remote (int from_tty
)
2295 struct inferior
*inferior
;
2297 inferior
= current_inferior ();
2298 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
2300 /* Always go on waiting for the target, regardless of the mode. */
2301 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2302 indicate to wait_for_inferior that a target should timeout if
2303 nothing is returned (instead of just blocking). Because of this,
2304 targets expecting an immediate response need to, internally, set
2305 things up so that the target_wait() is forced to eventually
2307 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2308 differentiate to its caller what the state of the target is after
2309 the initial open has been performed. Here we're assuming that
2310 the target has stopped. It should be possible to eventually have
2311 target_open() return to the caller an indication that the target
2312 is currently running and GDB state should be set to the same as
2313 for an async run. */
2314 wait_for_inferior ();
2316 /* Now that the inferior has stopped, do any bookkeeping like
2317 loading shared libraries. We want to do this before normal_stop,
2318 so that the displayed frame is up to date. */
2319 post_create_inferior (¤t_target
, from_tty
);
2324 /* Initialize static vars when a new inferior begins. */
2327 init_wait_for_inferior (void)
2329 /* These are meaningless until the first time through wait_for_inferior. */
2331 breakpoint_init_inferior (inf_starting
);
2333 clear_proceed_status ();
2335 stepping_past_singlestep_breakpoint
= 0;
2336 deferred_step_ptid
= null_ptid
;
2338 target_last_wait_ptid
= minus_one_ptid
;
2340 previous_inferior_ptid
= inferior_ptid
;
2341 init_infwait_state ();
2343 /* Discard any skipped inlined frames. */
2344 clear_inline_frame_state (minus_one_ptid
);
2348 /* This enum encodes possible reasons for doing a target_wait, so that
2349 wfi can call target_wait in one place. (Ultimately the call will be
2350 moved out of the infinite loop entirely.) */
2354 infwait_normal_state
,
2355 infwait_thread_hop_state
,
2356 infwait_step_watch_state
,
2357 infwait_nonstep_watch_state
2360 /* The PTID we'll do a target_wait on.*/
2363 /* Current inferior wait state. */
2364 enum infwait_states infwait_state
;
2366 /* Data to be passed around while handling an event. This data is
2367 discarded between events. */
2368 struct execution_control_state
2371 /* The thread that got the event, if this was a thread event; NULL
2373 struct thread_info
*event_thread
;
2375 struct target_waitstatus ws
;
2377 int stop_func_filled_in
;
2378 CORE_ADDR stop_func_start
;
2379 CORE_ADDR stop_func_end
;
2380 const char *stop_func_name
;
2384 static void handle_inferior_event (struct execution_control_state
*ecs
);
2386 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2387 struct execution_control_state
*ecs
);
2388 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2389 struct execution_control_state
*ecs
);
2390 static void check_exception_resume (struct execution_control_state
*,
2391 struct frame_info
*);
2393 static void stop_stepping (struct execution_control_state
*ecs
);
2394 static void prepare_to_wait (struct execution_control_state
*ecs
);
2395 static void keep_going (struct execution_control_state
*ecs
);
2397 /* Callback for iterate over threads. If the thread is stopped, but
2398 the user/frontend doesn't know about that yet, go through
2399 normal_stop, as if the thread had just stopped now. ARG points at
2400 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2401 ptid_is_pid(PTID) is true, applies to all threads of the process
2402 pointed at by PTID. Otherwise, apply only to the thread pointed by
2406 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2408 ptid_t ptid
= * (ptid_t
*) arg
;
2410 if ((ptid_equal (info
->ptid
, ptid
)
2411 || ptid_equal (minus_one_ptid
, ptid
)
2412 || (ptid_is_pid (ptid
)
2413 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2414 && is_running (info
->ptid
)
2415 && !is_executing (info
->ptid
))
2417 struct cleanup
*old_chain
;
2418 struct execution_control_state ecss
;
2419 struct execution_control_state
*ecs
= &ecss
;
2421 memset (ecs
, 0, sizeof (*ecs
));
2423 old_chain
= make_cleanup_restore_current_thread ();
2425 /* Go through handle_inferior_event/normal_stop, so we always
2426 have consistent output as if the stop event had been
2428 ecs
->ptid
= info
->ptid
;
2429 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2430 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2431 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
2433 handle_inferior_event (ecs
);
2435 if (!ecs
->wait_some_more
)
2437 struct thread_info
*tp
;
2441 /* Finish off the continuations. */
2442 tp
= inferior_thread ();
2443 do_all_intermediate_continuations_thread (tp
, 1);
2444 do_all_continuations_thread (tp
, 1);
2447 do_cleanups (old_chain
);
2453 /* This function is attached as a "thread_stop_requested" observer.
2454 Cleanup local state that assumed the PTID was to be resumed, and
2455 report the stop to the frontend. */
2458 infrun_thread_stop_requested (ptid_t ptid
)
2460 struct displaced_step_inferior_state
*displaced
;
2462 /* PTID was requested to stop. Remove it from the displaced
2463 stepping queue, so we don't try to resume it automatically. */
2465 for (displaced
= displaced_step_inferior_states
;
2467 displaced
= displaced
->next
)
2469 struct displaced_step_request
*it
, **prev_next_p
;
2471 it
= displaced
->step_request_queue
;
2472 prev_next_p
= &displaced
->step_request_queue
;
2475 if (ptid_match (it
->ptid
, ptid
))
2477 *prev_next_p
= it
->next
;
2483 prev_next_p
= &it
->next
;
2490 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2494 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2496 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2497 nullify_last_target_wait_ptid ();
2500 /* Callback for iterate_over_threads. */
2503 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
2505 if (is_exited (info
->ptid
))
2508 delete_step_resume_breakpoint (info
);
2509 delete_exception_resume_breakpoint (info
);
2513 /* In all-stop, delete the step resume breakpoint of any thread that
2514 had one. In non-stop, delete the step resume breakpoint of the
2515 thread that just stopped. */
2518 delete_step_thread_step_resume_breakpoint (void)
2520 if (!target_has_execution
2521 || ptid_equal (inferior_ptid
, null_ptid
))
2522 /* If the inferior has exited, we have already deleted the step
2523 resume breakpoints out of GDB's lists. */
2528 /* If in non-stop mode, only delete the step-resume or
2529 longjmp-resume breakpoint of the thread that just stopped
2531 struct thread_info
*tp
= inferior_thread ();
2533 delete_step_resume_breakpoint (tp
);
2534 delete_exception_resume_breakpoint (tp
);
2537 /* In all-stop mode, delete all step-resume and longjmp-resume
2538 breakpoints of any thread that had them. */
2539 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
2542 /* A cleanup wrapper. */
2545 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
2547 delete_step_thread_step_resume_breakpoint ();
2550 /* Pretty print the results of target_wait, for debugging purposes. */
2553 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
2554 const struct target_waitstatus
*ws
)
2556 char *status_string
= target_waitstatus_to_string (ws
);
2557 struct ui_file
*tmp_stream
= mem_fileopen ();
2560 /* The text is split over several lines because it was getting too long.
2561 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2562 output as a unit; we want only one timestamp printed if debug_timestamp
2565 fprintf_unfiltered (tmp_stream
,
2566 "infrun: target_wait (%d", PIDGET (waiton_ptid
));
2567 if (PIDGET (waiton_ptid
) != -1)
2568 fprintf_unfiltered (tmp_stream
,
2569 " [%s]", target_pid_to_str (waiton_ptid
));
2570 fprintf_unfiltered (tmp_stream
, ", status) =\n");
2571 fprintf_unfiltered (tmp_stream
,
2572 "infrun: %d [%s],\n",
2573 PIDGET (result_ptid
), target_pid_to_str (result_ptid
));
2574 fprintf_unfiltered (tmp_stream
,
2578 text
= ui_file_xstrdup (tmp_stream
, NULL
);
2580 /* This uses %s in part to handle %'s in the text, but also to avoid
2581 a gcc error: the format attribute requires a string literal. */
2582 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
2584 xfree (status_string
);
2586 ui_file_delete (tmp_stream
);
2589 /* Prepare and stabilize the inferior for detaching it. E.g.,
2590 detaching while a thread is displaced stepping is a recipe for
2591 crashing it, as nothing would readjust the PC out of the scratch
2595 prepare_for_detach (void)
2597 struct inferior
*inf
= current_inferior ();
2598 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
2599 struct cleanup
*old_chain_1
;
2600 struct displaced_step_inferior_state
*displaced
;
2602 displaced
= get_displaced_stepping_state (inf
->pid
);
2604 /* Is any thread of this process displaced stepping? If not,
2605 there's nothing else to do. */
2606 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
2610 fprintf_unfiltered (gdb_stdlog
,
2611 "displaced-stepping in-process while detaching");
2613 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
2616 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
2618 struct cleanup
*old_chain_2
;
2619 struct execution_control_state ecss
;
2620 struct execution_control_state
*ecs
;
2623 memset (ecs
, 0, sizeof (*ecs
));
2625 overlay_cache_invalid
= 1;
2627 if (deprecated_target_wait_hook
)
2628 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
2630 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
2633 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
2635 /* If an error happens while handling the event, propagate GDB's
2636 knowledge of the executing state to the frontend/user running
2638 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
2641 /* Now figure out what to do with the result of the result. */
2642 handle_inferior_event (ecs
);
2644 /* No error, don't finish the state yet. */
2645 discard_cleanups (old_chain_2
);
2647 /* Breakpoints and watchpoints are not installed on the target
2648 at this point, and signals are passed directly to the
2649 inferior, so this must mean the process is gone. */
2650 if (!ecs
->wait_some_more
)
2652 discard_cleanups (old_chain_1
);
2653 error (_("Program exited while detaching"));
2657 discard_cleanups (old_chain_1
);
2660 /* Wait for control to return from inferior to debugger.
2662 If inferior gets a signal, we may decide to start it up again
2663 instead of returning. That is why there is a loop in this function.
2664 When this function actually returns it means the inferior
2665 should be left stopped and GDB should read more commands. */
2668 wait_for_inferior (void)
2670 struct cleanup
*old_cleanups
;
2674 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
2677 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
2681 struct execution_control_state ecss
;
2682 struct execution_control_state
*ecs
= &ecss
;
2683 struct cleanup
*old_chain
;
2685 memset (ecs
, 0, sizeof (*ecs
));
2687 overlay_cache_invalid
= 1;
2689 if (deprecated_target_wait_hook
)
2690 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
2692 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
2695 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2697 /* If an error happens while handling the event, propagate GDB's
2698 knowledge of the executing state to the frontend/user running
2700 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2702 /* Now figure out what to do with the result of the result. */
2703 handle_inferior_event (ecs
);
2705 /* No error, don't finish the state yet. */
2706 discard_cleanups (old_chain
);
2708 if (!ecs
->wait_some_more
)
2712 do_cleanups (old_cleanups
);
2715 /* Asynchronous version of wait_for_inferior. It is called by the
2716 event loop whenever a change of state is detected on the file
2717 descriptor corresponding to the target. It can be called more than
2718 once to complete a single execution command. In such cases we need
2719 to keep the state in a global variable ECSS. If it is the last time
2720 that this function is called for a single execution command, then
2721 report to the user that the inferior has stopped, and do the
2722 necessary cleanups. */
2725 fetch_inferior_event (void *client_data
)
2727 struct execution_control_state ecss
;
2728 struct execution_control_state
*ecs
= &ecss
;
2729 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
2730 struct cleanup
*ts_old_chain
;
2731 int was_sync
= sync_execution
;
2734 memset (ecs
, 0, sizeof (*ecs
));
2736 /* We're handling a live event, so make sure we're doing live
2737 debugging. If we're looking at traceframes while the target is
2738 running, we're going to need to get back to that mode after
2739 handling the event. */
2742 make_cleanup_restore_current_traceframe ();
2743 set_current_traceframe (-1);
2747 /* In non-stop mode, the user/frontend should not notice a thread
2748 switch due to internal events. Make sure we reverse to the
2749 user selected thread and frame after handling the event and
2750 running any breakpoint commands. */
2751 make_cleanup_restore_current_thread ();
2753 overlay_cache_invalid
= 1;
2755 make_cleanup_restore_integer (&execution_direction
);
2756 execution_direction
= target_execution_direction ();
2758 if (deprecated_target_wait_hook
)
2760 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2762 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2765 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2767 /* If an error happens while handling the event, propagate GDB's
2768 knowledge of the executing state to the frontend/user running
2771 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2773 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
2775 /* Get executed before make_cleanup_restore_current_thread above to apply
2776 still for the thread which has thrown the exception. */
2777 make_bpstat_clear_actions_cleanup ();
2779 /* Now figure out what to do with the result of the result. */
2780 handle_inferior_event (ecs
);
2782 if (!ecs
->wait_some_more
)
2784 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2786 delete_step_thread_step_resume_breakpoint ();
2788 /* We may not find an inferior if this was a process exit. */
2789 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
2792 if (target_has_execution
2793 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
2794 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2795 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2796 && ecs
->event_thread
->step_multi
2797 && ecs
->event_thread
->control
.stop_step
)
2798 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
2801 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2806 /* No error, don't finish the thread states yet. */
2807 discard_cleanups (ts_old_chain
);
2809 /* Revert thread and frame. */
2810 do_cleanups (old_chain
);
2812 /* If the inferior was in sync execution mode, and now isn't,
2813 restore the prompt (a synchronous execution command has finished,
2814 and we're ready for input). */
2815 if (interpreter_async
&& was_sync
&& !sync_execution
)
2816 display_gdb_prompt (0);
2820 && exec_done_display_p
2821 && (ptid_equal (inferior_ptid
, null_ptid
)
2822 || !is_running (inferior_ptid
)))
2823 printf_unfiltered (_("completed.\n"));
2826 /* Record the frame and location we're currently stepping through. */
2828 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
2830 struct thread_info
*tp
= inferior_thread ();
2832 tp
->control
.step_frame_id
= get_frame_id (frame
);
2833 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
2835 tp
->current_symtab
= sal
.symtab
;
2836 tp
->current_line
= sal
.line
;
2839 /* Clear context switchable stepping state. */
2842 init_thread_stepping_state (struct thread_info
*tss
)
2844 tss
->stepping_over_breakpoint
= 0;
2845 tss
->step_after_step_resume_breakpoint
= 0;
2848 /* Return the cached copy of the last pid/waitstatus returned by
2849 target_wait()/deprecated_target_wait_hook(). The data is actually
2850 cached by handle_inferior_event(), which gets called immediately
2851 after target_wait()/deprecated_target_wait_hook(). */
2854 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
2856 *ptidp
= target_last_wait_ptid
;
2857 *status
= target_last_waitstatus
;
2861 nullify_last_target_wait_ptid (void)
2863 target_last_wait_ptid
= minus_one_ptid
;
2866 /* Switch thread contexts. */
2869 context_switch (ptid_t ptid
)
2871 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
2873 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
2874 target_pid_to_str (inferior_ptid
));
2875 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
2876 target_pid_to_str (ptid
));
2879 switch_to_thread (ptid
);
2883 adjust_pc_after_break (struct execution_control_state
*ecs
)
2885 struct regcache
*regcache
;
2886 struct gdbarch
*gdbarch
;
2887 struct address_space
*aspace
;
2888 CORE_ADDR breakpoint_pc
;
2890 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2891 we aren't, just return.
2893 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2894 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2895 implemented by software breakpoints should be handled through the normal
2898 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2899 different signals (SIGILL or SIGEMT for instance), but it is less
2900 clear where the PC is pointing afterwards. It may not match
2901 gdbarch_decr_pc_after_break. I don't know any specific target that
2902 generates these signals at breakpoints (the code has been in GDB since at
2903 least 1992) so I can not guess how to handle them here.
2905 In earlier versions of GDB, a target with
2906 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2907 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2908 target with both of these set in GDB history, and it seems unlikely to be
2909 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2911 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
2914 if (ecs
->ws
.value
.sig
!= GDB_SIGNAL_TRAP
)
2917 /* In reverse execution, when a breakpoint is hit, the instruction
2918 under it has already been de-executed. The reported PC always
2919 points at the breakpoint address, so adjusting it further would
2920 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2923 B1 0x08000000 : INSN1
2924 B2 0x08000001 : INSN2
2926 PC -> 0x08000003 : INSN4
2928 Say you're stopped at 0x08000003 as above. Reverse continuing
2929 from that point should hit B2 as below. Reading the PC when the
2930 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2931 been de-executed already.
2933 B1 0x08000000 : INSN1
2934 B2 PC -> 0x08000001 : INSN2
2938 We can't apply the same logic as for forward execution, because
2939 we would wrongly adjust the PC to 0x08000000, since there's a
2940 breakpoint at PC - 1. We'd then report a hit on B1, although
2941 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2943 if (execution_direction
== EXEC_REVERSE
)
2946 /* If this target does not decrement the PC after breakpoints, then
2947 we have nothing to do. */
2948 regcache
= get_thread_regcache (ecs
->ptid
);
2949 gdbarch
= get_regcache_arch (regcache
);
2950 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
2953 aspace
= get_regcache_aspace (regcache
);
2955 /* Find the location where (if we've hit a breakpoint) the
2956 breakpoint would be. */
2957 breakpoint_pc
= regcache_read_pc (regcache
)
2958 - gdbarch_decr_pc_after_break (gdbarch
);
2960 /* Check whether there actually is a software breakpoint inserted at
2963 If in non-stop mode, a race condition is possible where we've
2964 removed a breakpoint, but stop events for that breakpoint were
2965 already queued and arrive later. To suppress those spurious
2966 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
2967 and retire them after a number of stop events are reported. */
2968 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
2969 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
2971 struct cleanup
*old_cleanups
= NULL
;
2974 old_cleanups
= record_gdb_operation_disable_set ();
2976 /* When using hardware single-step, a SIGTRAP is reported for both
2977 a completed single-step and a software breakpoint. Need to
2978 differentiate between the two, as the latter needs adjusting
2979 but the former does not.
2981 The SIGTRAP can be due to a completed hardware single-step only if
2982 - we didn't insert software single-step breakpoints
2983 - the thread to be examined is still the current thread
2984 - this thread is currently being stepped
2986 If any of these events did not occur, we must have stopped due
2987 to hitting a software breakpoint, and have to back up to the
2990 As a special case, we could have hardware single-stepped a
2991 software breakpoint. In this case (prev_pc == breakpoint_pc),
2992 we also need to back up to the breakpoint address. */
2994 if (singlestep_breakpoints_inserted_p
2995 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
2996 || !currently_stepping (ecs
->event_thread
)
2997 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
2998 regcache_write_pc (regcache
, breakpoint_pc
);
3001 do_cleanups (old_cleanups
);
3006 init_infwait_state (void)
3008 waiton_ptid
= pid_to_ptid (-1);
3009 infwait_state
= infwait_normal_state
;
3013 error_is_running (void)
3015 error (_("Cannot execute this command while "
3016 "the selected thread is running."));
3020 ensure_not_running (void)
3022 if (is_running (inferior_ptid
))
3023 error_is_running ();
3027 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3029 for (frame
= get_prev_frame (frame
);
3031 frame
= get_prev_frame (frame
))
3033 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3035 if (get_frame_type (frame
) != INLINE_FRAME
)
3042 /* Auxiliary function that handles syscall entry/return events.
3043 It returns 1 if the inferior should keep going (and GDB
3044 should ignore the event), or 0 if the event deserves to be
3048 handle_syscall_event (struct execution_control_state
*ecs
)
3050 struct regcache
*regcache
;
3051 struct gdbarch
*gdbarch
;
3054 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3055 context_switch (ecs
->ptid
);
3057 regcache
= get_thread_regcache (ecs
->ptid
);
3058 gdbarch
= get_regcache_arch (regcache
);
3059 syscall_number
= ecs
->ws
.value
.syscall_number
;
3060 stop_pc
= regcache_read_pc (regcache
);
3062 if (catch_syscall_enabled () > 0
3063 && catching_syscall_number (syscall_number
) > 0)
3066 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3069 ecs
->event_thread
->control
.stop_bpstat
3070 = bpstat_stop_status (get_regcache_aspace (regcache
),
3071 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3073 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3075 if (!ecs
->random_signal
)
3077 /* Catchpoint hit. */
3078 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3083 /* If no catchpoint triggered for this, then keep going. */
3084 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3089 /* Clear the supplied execution_control_state's stop_func_* fields. */
3092 clear_stop_func (struct execution_control_state
*ecs
)
3094 ecs
->stop_func_filled_in
= 0;
3095 ecs
->stop_func_start
= 0;
3096 ecs
->stop_func_end
= 0;
3097 ecs
->stop_func_name
= NULL
;
3100 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3103 fill_in_stop_func (struct gdbarch
*gdbarch
,
3104 struct execution_control_state
*ecs
)
3106 if (!ecs
->stop_func_filled_in
)
3108 /* Don't care about return value; stop_func_start and stop_func_name
3109 will both be 0 if it doesn't work. */
3110 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3111 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3112 ecs
->stop_func_start
3113 += gdbarch_deprecated_function_start_offset (gdbarch
);
3115 ecs
->stop_func_filled_in
= 1;
3119 /* Given an execution control state that has been freshly filled in
3120 by an event from the inferior, figure out what it means and take
3121 appropriate action. */
3124 handle_inferior_event (struct execution_control_state
*ecs
)
3126 struct frame_info
*frame
;
3127 struct gdbarch
*gdbarch
;
3128 int stopped_by_watchpoint
;
3129 int stepped_after_stopped_by_watchpoint
= 0;
3130 struct symtab_and_line stop_pc_sal
;
3131 enum stop_kind stop_soon
;
3133 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3135 /* We had an event in the inferior, but we are not interested in
3136 handling it at this level. The lower layers have already
3137 done what needs to be done, if anything.
3139 One of the possible circumstances for this is when the
3140 inferior produces output for the console. The inferior has
3141 not stopped, and we are ignoring the event. Another possible
3142 circumstance is any event which the lower level knows will be
3143 reported multiple times without an intervening resume. */
3145 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3146 prepare_to_wait (ecs
);
3150 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3151 && target_can_async_p () && !sync_execution
)
3153 /* There were no unwaited-for children left in the target, but,
3154 we're not synchronously waiting for events either. Just
3155 ignore. Otherwise, if we were running a synchronous
3156 execution command, we need to cancel it and give the user
3157 back the terminal. */
3159 fprintf_unfiltered (gdb_stdlog
,
3160 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3161 prepare_to_wait (ecs
);
3165 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3166 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3167 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
3169 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3172 stop_soon
= inf
->control
.stop_soon
;
3175 stop_soon
= NO_STOP_QUIETLY
;
3177 /* Cache the last pid/waitstatus. */
3178 target_last_wait_ptid
= ecs
->ptid
;
3179 target_last_waitstatus
= ecs
->ws
;
3181 /* Always clear state belonging to the previous time we stopped. */
3182 stop_stack_dummy
= STOP_NONE
;
3184 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3186 /* No unwaited-for children left. IOW, all resumed children
3189 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3191 stop_print_frame
= 0;
3192 stop_stepping (ecs
);
3196 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3197 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3198 && !ptid_equal (ecs
->ptid
, minus_one_ptid
))
3200 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3201 /* If it's a new thread, add it to the thread database. */
3202 if (ecs
->event_thread
== NULL
)
3203 ecs
->event_thread
= add_thread (ecs
->ptid
);
3206 /* Dependent on valid ECS->EVENT_THREAD. */
3207 adjust_pc_after_break (ecs
);
3209 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3210 reinit_frame_cache ();
3212 breakpoint_retire_moribund ();
3214 /* First, distinguish signals caused by the debugger from signals
3215 that have to do with the program's own actions. Note that
3216 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3217 on the operating system version. Here we detect when a SIGILL or
3218 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3219 something similar for SIGSEGV, since a SIGSEGV will be generated
3220 when we're trying to execute a breakpoint instruction on a
3221 non-executable stack. This happens for call dummy breakpoints
3222 for architectures like SPARC that place call dummies on the
3224 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3225 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3226 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3227 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3229 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3231 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3232 regcache_read_pc (regcache
)))
3235 fprintf_unfiltered (gdb_stdlog
,
3236 "infrun: Treating signal as SIGTRAP\n");
3237 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3241 /* Mark the non-executing threads accordingly. In all-stop, all
3242 threads of all processes are stopped when we get any event
3243 reported. In non-stop mode, only the event thread stops. If
3244 we're handling a process exit in non-stop mode, there's nothing
3245 to do, as threads of the dead process are gone, and threads of
3246 any other process were left running. */
3248 set_executing (minus_one_ptid
, 0);
3249 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3250 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3251 set_executing (ecs
->ptid
, 0);
3253 switch (infwait_state
)
3255 case infwait_thread_hop_state
:
3257 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
3260 case infwait_normal_state
:
3262 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
3265 case infwait_step_watch_state
:
3267 fprintf_unfiltered (gdb_stdlog
,
3268 "infrun: infwait_step_watch_state\n");
3270 stepped_after_stopped_by_watchpoint
= 1;
3273 case infwait_nonstep_watch_state
:
3275 fprintf_unfiltered (gdb_stdlog
,
3276 "infrun: infwait_nonstep_watch_state\n");
3277 insert_breakpoints ();
3279 /* FIXME-maybe: is this cleaner than setting a flag? Does it
3280 handle things like signals arriving and other things happening
3281 in combination correctly? */
3282 stepped_after_stopped_by_watchpoint
= 1;
3286 internal_error (__FILE__
, __LINE__
, _("bad switch"));
3289 infwait_state
= infwait_normal_state
;
3290 waiton_ptid
= pid_to_ptid (-1);
3292 switch (ecs
->ws
.kind
)
3294 case TARGET_WAITKIND_LOADED
:
3296 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3297 /* Ignore gracefully during startup of the inferior, as it might
3298 be the shell which has just loaded some objects, otherwise
3299 add the symbols for the newly loaded objects. Also ignore at
3300 the beginning of an attach or remote session; we will query
3301 the full list of libraries once the connection is
3303 if (stop_soon
== NO_STOP_QUIETLY
)
3305 struct regcache
*regcache
;
3307 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3308 context_switch (ecs
->ptid
);
3309 regcache
= get_thread_regcache (ecs
->ptid
);
3311 handle_solib_event ();
3313 ecs
->event_thread
->control
.stop_bpstat
3314 = bpstat_stop_status (get_regcache_aspace (regcache
),
3315 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3317 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3319 if (!ecs
->random_signal
)
3321 /* A catchpoint triggered. */
3322 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3323 goto process_event_stop_test
;
3326 /* If requested, stop when the dynamic linker notifies
3327 gdb of events. This allows the user to get control
3328 and place breakpoints in initializer routines for
3329 dynamically loaded objects (among other things). */
3330 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3331 if (stop_on_solib_events
)
3333 /* Make sure we print "Stopped due to solib-event" in
3335 stop_print_frame
= 1;
3337 stop_stepping (ecs
);
3342 /* If we are skipping through a shell, or through shared library
3343 loading that we aren't interested in, resume the program. If
3344 we're running the program normally, also resume. But stop if
3345 we're attaching or setting up a remote connection. */
3346 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3348 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3349 context_switch (ecs
->ptid
);
3351 /* Loading of shared libraries might have changed breakpoint
3352 addresses. Make sure new breakpoints are inserted. */
3353 if (stop_soon
== NO_STOP_QUIETLY
3354 && !breakpoints_always_inserted_mode ())
3355 insert_breakpoints ();
3356 resume (0, GDB_SIGNAL_0
);
3357 prepare_to_wait (ecs
);
3363 case TARGET_WAITKIND_SPURIOUS
:
3365 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3366 if (!ptid_equal (ecs
->ptid
, inferior_ptid
)
3367 && !ptid_equal (ecs
->ptid
, minus_one_ptid
))
3368 context_switch (ecs
->ptid
);
3369 resume (0, GDB_SIGNAL_0
);
3370 prepare_to_wait (ecs
);
3373 case TARGET_WAITKIND_EXITED
:
3375 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
3376 inferior_ptid
= ecs
->ptid
;
3377 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3378 set_current_program_space (current_inferior ()->pspace
);
3379 handle_vfork_child_exec_or_exit (0);
3380 target_terminal_ours (); /* Must do this before mourn anyway. */
3381 print_exited_reason (ecs
->ws
.value
.integer
);
3383 /* Record the exit code in the convenience variable $_exitcode, so
3384 that the user can inspect this again later. */
3385 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3386 (LONGEST
) ecs
->ws
.value
.integer
);
3388 /* Also record this in the inferior itself. */
3389 current_inferior ()->has_exit_code
= 1;
3390 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3392 gdb_flush (gdb_stdout
);
3393 target_mourn_inferior ();
3394 singlestep_breakpoints_inserted_p
= 0;
3395 cancel_single_step_breakpoints ();
3396 stop_print_frame
= 0;
3397 stop_stepping (ecs
);
3400 case TARGET_WAITKIND_SIGNALLED
:
3402 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
3403 inferior_ptid
= ecs
->ptid
;
3404 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3405 set_current_program_space (current_inferior ()->pspace
);
3406 handle_vfork_child_exec_or_exit (0);
3407 stop_print_frame
= 0;
3408 target_terminal_ours (); /* Must do this before mourn anyway. */
3410 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
3411 reach here unless the inferior is dead. However, for years
3412 target_kill() was called here, which hints that fatal signals aren't
3413 really fatal on some systems. If that's true, then some changes
3415 target_mourn_inferior ();
3417 print_signal_exited_reason (ecs
->ws
.value
.sig
);
3418 singlestep_breakpoints_inserted_p
= 0;
3419 cancel_single_step_breakpoints ();
3420 stop_stepping (ecs
);
3423 /* The following are the only cases in which we keep going;
3424 the above cases end in a continue or goto. */
3425 case TARGET_WAITKIND_FORKED
:
3426 case TARGET_WAITKIND_VFORKED
:
3428 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3430 /* Check whether the inferior is displaced stepping. */
3432 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3433 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3434 struct displaced_step_inferior_state
*displaced
3435 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3437 /* If checking displaced stepping is supported, and thread
3438 ecs->ptid is displaced stepping. */
3439 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3441 struct inferior
*parent_inf
3442 = find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3443 struct regcache
*child_regcache
;
3444 CORE_ADDR parent_pc
;
3446 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3447 indicating that the displaced stepping of syscall instruction
3448 has been done. Perform cleanup for parent process here. Note
3449 that this operation also cleans up the child process for vfork,
3450 because their pages are shared. */
3451 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
3453 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3455 /* Restore scratch pad for child process. */
3456 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3459 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3460 the child's PC is also within the scratchpad. Set the child's PC
3461 to the parent's PC value, which has already been fixed up.
3462 FIXME: we use the parent's aspace here, although we're touching
3463 the child, because the child hasn't been added to the inferior
3464 list yet at this point. */
3467 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3469 parent_inf
->aspace
);
3470 /* Read PC value of parent process. */
3471 parent_pc
= regcache_read_pc (regcache
);
3473 if (debug_displaced
)
3474 fprintf_unfiltered (gdb_stdlog
,
3475 "displaced: write child pc from %s to %s\n",
3477 regcache_read_pc (child_regcache
)),
3478 paddress (gdbarch
, parent_pc
));
3480 regcache_write_pc (child_regcache
, parent_pc
);
3484 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3485 context_switch (ecs
->ptid
);
3487 /* Immediately detach breakpoints from the child before there's
3488 any chance of letting the user delete breakpoints from the
3489 breakpoint lists. If we don't do this early, it's easy to
3490 leave left over traps in the child, vis: "break foo; catch
3491 fork; c; <fork>; del; c; <child calls foo>". We only follow
3492 the fork on the last `continue', and by that time the
3493 breakpoint at "foo" is long gone from the breakpoint table.
3494 If we vforked, then we don't need to unpatch here, since both
3495 parent and child are sharing the same memory pages; we'll
3496 need to unpatch at follow/detach time instead to be certain
3497 that new breakpoints added between catchpoint hit time and
3498 vfork follow are detached. */
3499 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3501 int child_pid
= ptid_get_pid (ecs
->ws
.value
.related_pid
);
3503 /* This won't actually modify the breakpoint list, but will
3504 physically remove the breakpoints from the child. */
3505 detach_breakpoints (child_pid
);
3508 if (singlestep_breakpoints_inserted_p
)
3510 /* Pull the single step breakpoints out of the target. */
3511 remove_single_step_breakpoints ();
3512 singlestep_breakpoints_inserted_p
= 0;
3515 /* In case the event is caught by a catchpoint, remember that
3516 the event is to be followed at the next resume of the thread,
3517 and not immediately. */
3518 ecs
->event_thread
->pending_follow
= ecs
->ws
;
3520 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3522 ecs
->event_thread
->control
.stop_bpstat
3523 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3524 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3526 /* Note that we're interested in knowing the bpstat actually
3527 causes a stop, not just if it may explain the signal.
3528 Software watchpoints, for example, always appear in the
3531 = !bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
);
3533 /* If no catchpoint triggered for this, then keep going. */
3534 if (ecs
->random_signal
)
3540 = (follow_fork_mode_string
== follow_fork_mode_child
);
3542 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3544 should_resume
= follow_fork ();
3547 child
= ecs
->ws
.value
.related_pid
;
3549 /* In non-stop mode, also resume the other branch. */
3550 if (non_stop
&& !detach_fork
)
3553 switch_to_thread (parent
);
3555 switch_to_thread (child
);
3557 ecs
->event_thread
= inferior_thread ();
3558 ecs
->ptid
= inferior_ptid
;
3563 switch_to_thread (child
);
3565 switch_to_thread (parent
);
3567 ecs
->event_thread
= inferior_thread ();
3568 ecs
->ptid
= inferior_ptid
;
3573 stop_stepping (ecs
);
3576 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3577 goto process_event_stop_test
;
3579 case TARGET_WAITKIND_VFORK_DONE
:
3580 /* Done with the shared memory region. Re-insert breakpoints in
3581 the parent, and keep going. */
3584 fprintf_unfiltered (gdb_stdlog
,
3585 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3587 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3588 context_switch (ecs
->ptid
);
3590 current_inferior ()->waiting_for_vfork_done
= 0;
3591 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
3592 /* This also takes care of reinserting breakpoints in the
3593 previously locked inferior. */
3597 case TARGET_WAITKIND_EXECD
:
3599 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
3601 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3602 context_switch (ecs
->ptid
);
3604 singlestep_breakpoints_inserted_p
= 0;
3605 cancel_single_step_breakpoints ();
3607 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3609 /* Do whatever is necessary to the parent branch of the vfork. */
3610 handle_vfork_child_exec_or_exit (1);
3612 /* This causes the eventpoints and symbol table to be reset.
3613 Must do this now, before trying to determine whether to
3615 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
3617 ecs
->event_thread
->control
.stop_bpstat
3618 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3619 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3621 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3623 /* Note that this may be referenced from inside
3624 bpstat_stop_status above, through inferior_has_execd. */
3625 xfree (ecs
->ws
.value
.execd_pathname
);
3626 ecs
->ws
.value
.execd_pathname
= NULL
;
3628 /* If no catchpoint triggered for this, then keep going. */
3629 if (ecs
->random_signal
)
3631 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3635 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3636 goto process_event_stop_test
;
3638 /* Be careful not to try to gather much state about a thread
3639 that's in a syscall. It's frequently a losing proposition. */
3640 case TARGET_WAITKIND_SYSCALL_ENTRY
:
3642 fprintf_unfiltered (gdb_stdlog
,
3643 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3644 /* Getting the current syscall number. */
3645 if (handle_syscall_event (ecs
) != 0)
3647 goto process_event_stop_test
;
3649 /* Before examining the threads further, step this thread to
3650 get it entirely out of the syscall. (We get notice of the
3651 event when the thread is just on the verge of exiting a
3652 syscall. Stepping one instruction seems to get it back
3654 case TARGET_WAITKIND_SYSCALL_RETURN
:
3656 fprintf_unfiltered (gdb_stdlog
,
3657 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3658 if (handle_syscall_event (ecs
) != 0)
3660 goto process_event_stop_test
;
3662 case TARGET_WAITKIND_STOPPED
:
3664 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
3665 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
3668 case TARGET_WAITKIND_NO_HISTORY
:
3670 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
3671 /* Reverse execution: target ran out of history info. */
3673 /* Pull the single step breakpoints out of the target. */
3674 if (singlestep_breakpoints_inserted_p
)
3676 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3677 context_switch (ecs
->ptid
);
3678 remove_single_step_breakpoints ();
3679 singlestep_breakpoints_inserted_p
= 0;
3681 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3682 print_no_history_reason ();
3683 stop_stepping (ecs
);
3687 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
3689 /* Do we need to clean up the state of a thread that has
3690 completed a displaced single-step? (Doing so usually affects
3691 the PC, so do it here, before we set stop_pc.) */
3692 displaced_step_fixup (ecs
->ptid
,
3693 ecs
->event_thread
->suspend
.stop_signal
);
3695 /* If we either finished a single-step or hit a breakpoint, but
3696 the user wanted this thread to be stopped, pretend we got a
3697 SIG0 (generic unsignaled stop). */
3699 if (ecs
->event_thread
->stop_requested
3700 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3701 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3704 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3708 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3709 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3710 struct cleanup
*old_chain
= save_inferior_ptid ();
3712 inferior_ptid
= ecs
->ptid
;
3714 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
3715 paddress (gdbarch
, stop_pc
));
3716 if (target_stopped_by_watchpoint ())
3720 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
3722 if (target_stopped_data_address (¤t_target
, &addr
))
3723 fprintf_unfiltered (gdb_stdlog
,
3724 "infrun: stopped data address = %s\n",
3725 paddress (gdbarch
, addr
));
3727 fprintf_unfiltered (gdb_stdlog
,
3728 "infrun: (no data address available)\n");
3731 do_cleanups (old_chain
);
3734 if (stepping_past_singlestep_breakpoint
)
3736 gdb_assert (singlestep_breakpoints_inserted_p
);
3737 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
3738 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
3740 stepping_past_singlestep_breakpoint
= 0;
3742 /* We've either finished single-stepping past the single-step
3743 breakpoint, or stopped for some other reason. It would be nice if
3744 we could tell, but we can't reliably. */
3745 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3748 fprintf_unfiltered (gdb_stdlog
,
3749 "infrun: stepping_past_"
3750 "singlestep_breakpoint\n");
3751 /* Pull the single step breakpoints out of the target. */
3752 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3753 context_switch (ecs
->ptid
);
3754 remove_single_step_breakpoints ();
3755 singlestep_breakpoints_inserted_p
= 0;
3757 ecs
->random_signal
= 0;
3758 ecs
->event_thread
->control
.trap_expected
= 0;
3760 context_switch (saved_singlestep_ptid
);
3761 if (deprecated_context_hook
)
3762 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3764 resume (1, GDB_SIGNAL_0
);
3765 prepare_to_wait (ecs
);
3770 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
3772 /* In non-stop mode, there's never a deferred_step_ptid set. */
3773 gdb_assert (!non_stop
);
3775 /* If we stopped for some other reason than single-stepping, ignore
3776 the fact that we were supposed to switch back. */
3777 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3780 fprintf_unfiltered (gdb_stdlog
,
3781 "infrun: handling deferred step\n");
3783 /* Pull the single step breakpoints out of the target. */
3784 if (singlestep_breakpoints_inserted_p
)
3786 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3787 context_switch (ecs
->ptid
);
3788 remove_single_step_breakpoints ();
3789 singlestep_breakpoints_inserted_p
= 0;
3792 ecs
->event_thread
->control
.trap_expected
= 0;
3794 context_switch (deferred_step_ptid
);
3795 deferred_step_ptid
= null_ptid
;
3796 /* Suppress spurious "Switching to ..." message. */
3797 previous_inferior_ptid
= inferior_ptid
;
3799 resume (1, GDB_SIGNAL_0
);
3800 prepare_to_wait (ecs
);
3804 deferred_step_ptid
= null_ptid
;
3807 /* See if a thread hit a thread-specific breakpoint that was meant for
3808 another thread. If so, then step that thread past the breakpoint,
3811 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3813 int thread_hop_needed
= 0;
3814 struct address_space
*aspace
=
3815 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
3817 /* Check if a regular breakpoint has been hit before checking
3818 for a potential single step breakpoint. Otherwise, GDB will
3819 not see this breakpoint hit when stepping onto breakpoints. */
3820 if (regular_breakpoint_inserted_here_p (aspace
, stop_pc
))
3822 ecs
->random_signal
= 0;
3823 if (!breakpoint_thread_match (aspace
, stop_pc
, ecs
->ptid
))
3824 thread_hop_needed
= 1;
3826 else if (singlestep_breakpoints_inserted_p
)
3828 /* We have not context switched yet, so this should be true
3829 no matter which thread hit the singlestep breakpoint. */
3830 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
3832 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
3834 target_pid_to_str (ecs
->ptid
));
3836 ecs
->random_signal
= 0;
3837 /* The call to in_thread_list is necessary because PTIDs sometimes
3838 change when we go from single-threaded to multi-threaded. If
3839 the singlestep_ptid is still in the list, assume that it is
3840 really different from ecs->ptid. */
3841 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
3842 && in_thread_list (singlestep_ptid
))
3844 /* If the PC of the thread we were trying to single-step
3845 has changed, discard this event (which we were going
3846 to ignore anyway), and pretend we saw that thread
3847 trap. This prevents us continuously moving the
3848 single-step breakpoint forward, one instruction at a
3849 time. If the PC has changed, then the thread we were
3850 trying to single-step has trapped or been signalled,
3851 but the event has not been reported to GDB yet.
3853 There might be some cases where this loses signal
3854 information, if a signal has arrived at exactly the
3855 same time that the PC changed, but this is the best
3856 we can do with the information available. Perhaps we
3857 should arrange to report all events for all threads
3858 when they stop, or to re-poll the remote looking for
3859 this particular thread (i.e. temporarily enable
3862 CORE_ADDR new_singlestep_pc
3863 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
3865 if (new_singlestep_pc
!= singlestep_pc
)
3867 enum gdb_signal stop_signal
;
3870 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
3871 " but expected thread advanced also\n");
3873 /* The current context still belongs to
3874 singlestep_ptid. Don't swap here, since that's
3875 the context we want to use. Just fudge our
3876 state and continue. */
3877 stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
3878 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3879 ecs
->ptid
= singlestep_ptid
;
3880 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3881 ecs
->event_thread
->suspend
.stop_signal
= stop_signal
;
3882 stop_pc
= new_singlestep_pc
;
3887 fprintf_unfiltered (gdb_stdlog
,
3888 "infrun: unexpected thread\n");
3890 thread_hop_needed
= 1;
3891 stepping_past_singlestep_breakpoint
= 1;
3892 saved_singlestep_ptid
= singlestep_ptid
;
3897 if (thread_hop_needed
)
3899 struct regcache
*thread_regcache
;
3900 int remove_status
= 0;
3903 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
3905 /* Switch context before touching inferior memory, the
3906 previous thread may have exited. */
3907 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
3908 context_switch (ecs
->ptid
);
3910 /* Saw a breakpoint, but it was hit by the wrong thread.
3913 if (singlestep_breakpoints_inserted_p
)
3915 /* Pull the single step breakpoints out of the target. */
3916 remove_single_step_breakpoints ();
3917 singlestep_breakpoints_inserted_p
= 0;
3920 /* If the arch can displace step, don't remove the
3922 thread_regcache
= get_thread_regcache (ecs
->ptid
);
3923 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
3924 remove_status
= remove_breakpoints ();
3926 /* Did we fail to remove breakpoints? If so, try
3927 to set the PC past the bp. (There's at least
3928 one situation in which we can fail to remove
3929 the bp's: On HP-UX's that use ttrace, we can't
3930 change the address space of a vforking child
3931 process until the child exits (well, okay, not
3932 then either :-) or execs. */
3933 if (remove_status
!= 0)
3934 error (_("Cannot step over breakpoint hit in wrong thread"));
3939 /* Only need to require the next event from this
3940 thread in all-stop mode. */
3941 waiton_ptid
= ecs
->ptid
;
3942 infwait_state
= infwait_thread_hop_state
;
3945 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3950 else if (singlestep_breakpoints_inserted_p
)
3952 ecs
->random_signal
= 0;
3956 ecs
->random_signal
= 1;
3958 /* See if something interesting happened to the non-current thread. If
3959 so, then switch to that thread. */
3960 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3963 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
3965 context_switch (ecs
->ptid
);
3967 if (deprecated_context_hook
)
3968 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3971 /* At this point, get hold of the now-current thread's frame. */
3972 frame
= get_current_frame ();
3973 gdbarch
= get_frame_arch (frame
);
3975 if (singlestep_breakpoints_inserted_p
)
3977 /* Pull the single step breakpoints out of the target. */
3978 remove_single_step_breakpoints ();
3979 singlestep_breakpoints_inserted_p
= 0;
3982 if (stepped_after_stopped_by_watchpoint
)
3983 stopped_by_watchpoint
= 0;
3985 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
3987 /* If necessary, step over this watchpoint. We'll be back to display
3989 if (stopped_by_watchpoint
3990 && (target_have_steppable_watchpoint
3991 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
3993 /* At this point, we are stopped at an instruction which has
3994 attempted to write to a piece of memory under control of
3995 a watchpoint. The instruction hasn't actually executed
3996 yet. If we were to evaluate the watchpoint expression
3997 now, we would get the old value, and therefore no change
3998 would seem to have occurred.
4000 In order to make watchpoints work `right', we really need
4001 to complete the memory write, and then evaluate the
4002 watchpoint expression. We do this by single-stepping the
4005 It may not be necessary to disable the watchpoint to stop over
4006 it. For example, the PA can (with some kernel cooperation)
4007 single step over a watchpoint without disabling the watchpoint.
4009 It is far more common to need to disable a watchpoint to step
4010 the inferior over it. If we have non-steppable watchpoints,
4011 we must disable the current watchpoint; it's simplest to
4012 disable all watchpoints and breakpoints. */
4015 if (!target_have_steppable_watchpoint
)
4017 remove_breakpoints ();
4018 /* See comment in resume why we need to stop bypassing signals
4019 while breakpoints have been removed. */
4020 target_pass_signals (0, NULL
);
4023 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
4024 target_resume (ecs
->ptid
, hw_step
, GDB_SIGNAL_0
);
4025 waiton_ptid
= ecs
->ptid
;
4026 if (target_have_steppable_watchpoint
)
4027 infwait_state
= infwait_step_watch_state
;
4029 infwait_state
= infwait_nonstep_watch_state
;
4030 prepare_to_wait (ecs
);
4034 clear_stop_func (ecs
);
4035 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4036 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4037 ecs
->event_thread
->control
.stop_step
= 0;
4038 stop_print_frame
= 1;
4039 ecs
->random_signal
= 0;
4040 stopped_by_random_signal
= 0;
4042 /* Hide inlined functions starting here, unless we just performed stepi or
4043 nexti. After stepi and nexti, always show the innermost frame (not any
4044 inline function call sites). */
4045 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4047 struct address_space
*aspace
=
4048 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4050 /* skip_inline_frames is expensive, so we avoid it if we can
4051 determine that the address is one where functions cannot have
4052 been inlined. This improves performance with inferiors that
4053 load a lot of shared libraries, because the solib event
4054 breakpoint is defined as the address of a function (i.e. not
4055 inline). Note that we have to check the previous PC as well
4056 as the current one to catch cases when we have just
4057 single-stepped off a breakpoint prior to reinstating it.
4058 Note that we're assuming that the code we single-step to is
4059 not inline, but that's not definitive: there's nothing
4060 preventing the event breakpoint function from containing
4061 inlined code, and the single-step ending up there. If the
4062 user had set a breakpoint on that inlined code, the missing
4063 skip_inline_frames call would break things. Fortunately
4064 that's an extremely unlikely scenario. */
4065 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4066 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4067 && ecs
->event_thread
->control
.trap_expected
4068 && pc_at_non_inline_function (aspace
,
4069 ecs
->event_thread
->prev_pc
,
4072 skip_inline_frames (ecs
->ptid
);
4074 /* Re-fetch current thread's frame in case that invalidated
4076 frame
= get_current_frame ();
4077 gdbarch
= get_frame_arch (frame
);
4081 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4082 && ecs
->event_thread
->control
.trap_expected
4083 && gdbarch_single_step_through_delay_p (gdbarch
)
4084 && currently_stepping (ecs
->event_thread
))
4086 /* We're trying to step off a breakpoint. Turns out that we're
4087 also on an instruction that needs to be stepped multiple
4088 times before it's been fully executing. E.g., architectures
4089 with a delay slot. It needs to be stepped twice, once for
4090 the instruction and once for the delay slot. */
4091 int step_through_delay
4092 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4094 if (debug_infrun
&& step_through_delay
)
4095 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4096 if (ecs
->event_thread
->control
.step_range_end
== 0
4097 && step_through_delay
)
4099 /* The user issued a continue when stopped at a breakpoint.
4100 Set up for another trap and get out of here. */
4101 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4105 else if (step_through_delay
)
4107 /* The user issued a step when stopped at a breakpoint.
4108 Maybe we should stop, maybe we should not - the delay
4109 slot *might* correspond to a line of source. In any
4110 case, don't decide that here, just set
4111 ecs->stepping_over_breakpoint, making sure we
4112 single-step again before breakpoints are re-inserted. */
4113 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4117 /* Look at the cause of the stop, and decide what to do.
4118 The alternatives are:
4119 1) stop_stepping and return; to really stop and return to the debugger,
4120 2) keep_going and return to start up again
4121 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
4122 3) set ecs->random_signal to 1, and the decision between 1 and 2
4123 will be made according to the signal handling tables. */
4125 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4126 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4127 || stop_soon
== STOP_QUIETLY_REMOTE
)
4129 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4133 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4134 stop_print_frame
= 0;
4135 stop_stepping (ecs
);
4139 /* This is originated from start_remote(), start_inferior() and
4140 shared libraries hook functions. */
4141 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4144 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4145 stop_stepping (ecs
);
4149 /* This originates from attach_command(). We need to overwrite
4150 the stop_signal here, because some kernels don't ignore a
4151 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4152 See more comments in inferior.h. On the other hand, if we
4153 get a non-SIGSTOP, report it to the user - assume the backend
4154 will handle the SIGSTOP if it should show up later.
4156 Also consider that the attach is complete when we see a
4157 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4158 target extended-remote report it instead of a SIGSTOP
4159 (e.g. gdbserver). We already rely on SIGTRAP being our
4160 signal, so this is no exception.
4162 Also consider that the attach is complete when we see a
4163 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4164 the target to stop all threads of the inferior, in case the
4165 low level attach operation doesn't stop them implicitly. If
4166 they weren't stopped implicitly, then the stub will report a
4167 GDB_SIGNAL_0, meaning: stopped for no particular reason
4168 other than GDB's request. */
4169 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4170 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
4171 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4172 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
4174 stop_stepping (ecs
);
4175 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4179 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4180 handles this event. */
4181 ecs
->event_thread
->control
.stop_bpstat
4182 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4183 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4185 /* Following in case break condition called a
4187 stop_print_frame
= 1;
4189 /* This is where we handle "moribund" watchpoints. Unlike
4190 software breakpoints traps, hardware watchpoint traps are
4191 always distinguishable from random traps. If no high-level
4192 watchpoint is associated with the reported stop data address
4193 anymore, then the bpstat does not explain the signal ---
4194 simply make sure to ignore it if `stopped_by_watchpoint' is
4198 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4199 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4200 && stopped_by_watchpoint
)
4201 fprintf_unfiltered (gdb_stdlog
,
4202 "infrun: no user watchpoint explains "
4203 "watchpoint SIGTRAP, ignoring\n");
4205 /* NOTE: cagney/2003-03-29: These two checks for a random signal
4206 at one stage in the past included checks for an inferior
4207 function call's call dummy's return breakpoint. The original
4208 comment, that went with the test, read:
4210 ``End of a stack dummy. Some systems (e.g. Sony news) give
4211 another signal besides SIGTRAP, so check here as well as
4214 If someone ever tries to get call dummys on a
4215 non-executable stack to work (where the target would stop
4216 with something like a SIGSEGV), then those tests might need
4217 to be re-instated. Given, however, that the tests were only
4218 enabled when momentary breakpoints were not being used, I
4219 suspect that it won't be the case.
4221 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4222 be necessary for call dummies on a non-executable stack on
4225 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4227 = !(bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4228 || stopped_by_watchpoint
4229 || ecs
->event_thread
->control
.trap_expected
4230 || (ecs
->event_thread
->control
.step_range_end
4231 && (ecs
->event_thread
->control
.step_resume_breakpoint
4235 ecs
->random_signal
= !bpstat_explains_signal
4236 (ecs
->event_thread
->control
.stop_bpstat
);
4237 if (!ecs
->random_signal
)
4238 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
4242 /* When we reach this point, we've pretty much decided
4243 that the reason for stopping must've been a random
4244 (unexpected) signal. */
4247 ecs
->random_signal
= 1;
4249 process_event_stop_test
:
4251 /* Re-fetch current thread's frame in case we did a
4252 "goto process_event_stop_test" above. */
4253 frame
= get_current_frame ();
4254 gdbarch
= get_frame_arch (frame
);
4256 /* For the program's own signals, act according to
4257 the signal handling tables. */
4259 if (ecs
->random_signal
)
4261 /* Signal not for debugging purposes. */
4263 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
4266 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
4267 ecs
->event_thread
->suspend
.stop_signal
);
4269 stopped_by_random_signal
= 1;
4271 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4274 target_terminal_ours_for_output ();
4275 print_signal_received_reason
4276 (ecs
->event_thread
->suspend
.stop_signal
);
4278 /* Always stop on signals if we're either just gaining control
4279 of the program, or the user explicitly requested this thread
4280 to remain stopped. */
4281 if (stop_soon
!= NO_STOP_QUIETLY
4282 || ecs
->event_thread
->stop_requested
4284 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4286 stop_stepping (ecs
);
4289 /* If not going to stop, give terminal back
4290 if we took it away. */
4292 target_terminal_inferior ();
4294 /* Clear the signal if it should not be passed. */
4295 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4296 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4298 if (ecs
->event_thread
->prev_pc
== stop_pc
4299 && ecs
->event_thread
->control
.trap_expected
4300 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4302 /* We were just starting a new sequence, attempting to
4303 single-step off of a breakpoint and expecting a SIGTRAP.
4304 Instead this signal arrives. This signal will take us out
4305 of the stepping range so GDB needs to remember to, when
4306 the signal handler returns, resume stepping off that
4308 /* To simplify things, "continue" is forced to use the same
4309 code paths as single-step - set a breakpoint at the
4310 signal return address and then, once hit, step off that
4313 fprintf_unfiltered (gdb_stdlog
,
4314 "infrun: signal arrived while stepping over "
4317 insert_hp_step_resume_breakpoint_at_frame (frame
);
4318 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4319 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4320 ecs
->event_thread
->control
.trap_expected
= 0;
4325 if (ecs
->event_thread
->control
.step_range_end
!= 0
4326 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4327 && (ecs
->event_thread
->control
.step_range_start
<= stop_pc
4328 && stop_pc
< ecs
->event_thread
->control
.step_range_end
)
4329 && frame_id_eq (get_stack_frame_id (frame
),
4330 ecs
->event_thread
->control
.step_stack_frame_id
)
4331 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4333 /* The inferior is about to take a signal that will take it
4334 out of the single step range. Set a breakpoint at the
4335 current PC (which is presumably where the signal handler
4336 will eventually return) and then allow the inferior to
4339 Note that this is only needed for a signal delivered
4340 while in the single-step range. Nested signals aren't a
4341 problem as they eventually all return. */
4343 fprintf_unfiltered (gdb_stdlog
,
4344 "infrun: signal may take us out of "
4345 "single-step range\n");
4347 insert_hp_step_resume_breakpoint_at_frame (frame
);
4348 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4349 ecs
->event_thread
->control
.trap_expected
= 0;
4354 /* Note: step_resume_breakpoint may be non-NULL. This occures
4355 when either there's a nested signal, or when there's a
4356 pending signal enabled just as the signal handler returns
4357 (leaving the inferior at the step-resume-breakpoint without
4358 actually executing it). Either way continue until the
4359 breakpoint is really hit. */
4363 /* Handle cases caused by hitting a breakpoint. */
4365 CORE_ADDR jmp_buf_pc
;
4366 struct bpstat_what what
;
4368 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4370 if (what
.call_dummy
)
4372 stop_stack_dummy
= what
.call_dummy
;
4375 /* If we hit an internal event that triggers symbol changes, the
4376 current frame will be invalidated within bpstat_what (e.g.,
4377 if we hit an internal solib event). Re-fetch it. */
4378 frame
= get_current_frame ();
4379 gdbarch
= get_frame_arch (frame
);
4381 switch (what
.main_action
)
4383 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4384 /* If we hit the breakpoint at longjmp while stepping, we
4385 install a momentary breakpoint at the target of the
4389 fprintf_unfiltered (gdb_stdlog
,
4390 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4392 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4394 if (what
.is_longjmp
)
4396 struct value
*arg_value
;
4398 /* If we set the longjmp breakpoint via a SystemTap
4399 probe, then use it to extract the arguments. The
4400 destination PC is the third argument to the
4402 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4404 jmp_buf_pc
= value_as_address (arg_value
);
4405 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4406 || !gdbarch_get_longjmp_target (gdbarch
,
4407 frame
, &jmp_buf_pc
))
4410 fprintf_unfiltered (gdb_stdlog
,
4411 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4412 "(!gdbarch_get_longjmp_target)\n");
4417 /* Insert a breakpoint at resume address. */
4418 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4421 check_exception_resume (ecs
, frame
);
4425 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4427 struct frame_info
*init_frame
;
4429 /* There are several cases to consider.
4431 1. The initiating frame no longer exists. In this case
4432 we must stop, because the exception or longjmp has gone
4435 2. The initiating frame exists, and is the same as the
4436 current frame. We stop, because the exception or
4437 longjmp has been caught.
4439 3. The initiating frame exists and is different from
4440 the current frame. This means the exception or longjmp
4441 has been caught beneath the initiating frame, so keep
4444 4. longjmp breakpoint has been placed just to protect
4445 against stale dummy frames and user is not interested
4446 in stopping around longjmps. */
4449 fprintf_unfiltered (gdb_stdlog
,
4450 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4452 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4454 delete_exception_resume_breakpoint (ecs
->event_thread
);
4456 if (what
.is_longjmp
)
4458 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
->num
);
4460 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
4468 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4472 struct frame_id current_id
4473 = get_frame_id (get_current_frame ());
4474 if (frame_id_eq (current_id
,
4475 ecs
->event_thread
->initiating_frame
))
4477 /* Case 2. Fall through. */
4487 /* For Cases 1 and 2, remove the step-resume breakpoint,
4489 delete_step_resume_breakpoint (ecs
->event_thread
);
4491 ecs
->event_thread
->control
.stop_step
= 1;
4492 print_end_stepping_range_reason ();
4493 stop_stepping (ecs
);
4497 case BPSTAT_WHAT_SINGLE
:
4499 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4500 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4501 /* Still need to check other stuff, at least the case where
4502 we are stepping and step out of the right range. */
4505 case BPSTAT_WHAT_STEP_RESUME
:
4507 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4509 delete_step_resume_breakpoint (ecs
->event_thread
);
4510 if (ecs
->event_thread
->control
.proceed_to_finish
4511 && execution_direction
== EXEC_REVERSE
)
4513 struct thread_info
*tp
= ecs
->event_thread
;
4515 /* We are finishing a function in reverse, and just hit
4516 the step-resume breakpoint at the start address of
4517 the function, and we're almost there -- just need to
4518 back up by one more single-step, which should take us
4519 back to the function call. */
4520 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4524 fill_in_stop_func (gdbarch
, ecs
);
4525 if (stop_pc
== ecs
->stop_func_start
4526 && execution_direction
== EXEC_REVERSE
)
4528 /* We are stepping over a function call in reverse, and
4529 just hit the step-resume breakpoint at the start
4530 address of the function. Go back to single-stepping,
4531 which should take us back to the function call. */
4532 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4538 case BPSTAT_WHAT_STOP_NOISY
:
4540 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4541 stop_print_frame
= 1;
4543 /* We are about to nuke the step_resume_breakpointt via the
4544 cleanup chain, so no need to worry about it here. */
4546 stop_stepping (ecs
);
4549 case BPSTAT_WHAT_STOP_SILENT
:
4551 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4552 stop_print_frame
= 0;
4554 /* We are about to nuke the step_resume_breakpoin via the
4555 cleanup chain, so no need to worry about it here. */
4557 stop_stepping (ecs
);
4560 case BPSTAT_WHAT_HP_STEP_RESUME
:
4562 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4564 delete_step_resume_breakpoint (ecs
->event_thread
);
4565 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4567 /* Back when the step-resume breakpoint was inserted, we
4568 were trying to single-step off a breakpoint. Go back
4570 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4571 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4577 case BPSTAT_WHAT_KEEP_CHECKING
:
4582 /* We come here if we hit a breakpoint but should not
4583 stop for it. Possibly we also were stepping
4584 and should stop for that. So fall through and
4585 test for stepping. But, if not stepping,
4588 /* In all-stop mode, if we're currently stepping but have stopped in
4589 some other thread, we need to switch back to the stepped thread. */
4592 struct thread_info
*tp
;
4594 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
4598 /* However, if the current thread is blocked on some internal
4599 breakpoint, and we simply need to step over that breakpoint
4600 to get it going again, do that first. */
4601 if ((ecs
->event_thread
->control
.trap_expected
4602 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
4603 || ecs
->event_thread
->stepping_over_breakpoint
)
4609 /* If the stepping thread exited, then don't try to switch
4610 back and resume it, which could fail in several different
4611 ways depending on the target. Instead, just keep going.
4613 We can find a stepping dead thread in the thread list in
4616 - The target supports thread exit events, and when the
4617 target tries to delete the thread from the thread list,
4618 inferior_ptid pointed at the exiting thread. In such
4619 case, calling delete_thread does not really remove the
4620 thread from the list; instead, the thread is left listed,
4621 with 'exited' state.
4623 - The target's debug interface does not support thread
4624 exit events, and so we have no idea whatsoever if the
4625 previously stepping thread is still alive. For that
4626 reason, we need to synchronously query the target
4628 if (is_exited (tp
->ptid
)
4629 || !target_thread_alive (tp
->ptid
))
4632 fprintf_unfiltered (gdb_stdlog
,
4633 "infrun: not switching back to "
4634 "stepped thread, it has vanished\n");
4636 delete_thread (tp
->ptid
);
4641 /* Otherwise, we no longer expect a trap in the current thread.
4642 Clear the trap_expected flag before switching back -- this is
4643 what keep_going would do as well, if we called it. */
4644 ecs
->event_thread
->control
.trap_expected
= 0;
4647 fprintf_unfiltered (gdb_stdlog
,
4648 "infrun: switching back to stepped thread\n");
4650 ecs
->event_thread
= tp
;
4651 ecs
->ptid
= tp
->ptid
;
4652 context_switch (ecs
->ptid
);
4658 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4661 fprintf_unfiltered (gdb_stdlog
,
4662 "infrun: step-resume breakpoint is inserted\n");
4664 /* Having a step-resume breakpoint overrides anything
4665 else having to do with stepping commands until
4666 that breakpoint is reached. */
4671 if (ecs
->event_thread
->control
.step_range_end
== 0)
4674 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4675 /* Likewise if we aren't even stepping. */
4680 /* Re-fetch current thread's frame in case the code above caused
4681 the frame cache to be re-initialized, making our FRAME variable
4682 a dangling pointer. */
4683 frame
= get_current_frame ();
4684 gdbarch
= get_frame_arch (frame
);
4685 fill_in_stop_func (gdbarch
, ecs
);
4687 /* If stepping through a line, keep going if still within it.
4689 Note that step_range_end is the address of the first instruction
4690 beyond the step range, and NOT the address of the last instruction
4693 Note also that during reverse execution, we may be stepping
4694 through a function epilogue and therefore must detect when
4695 the current-frame changes in the middle of a line. */
4697 if (stop_pc
>= ecs
->event_thread
->control
.step_range_start
4698 && stop_pc
< ecs
->event_thread
->control
.step_range_end
4699 && (execution_direction
!= EXEC_REVERSE
4700 || frame_id_eq (get_frame_id (frame
),
4701 ecs
->event_thread
->control
.step_frame_id
)))
4705 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4706 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4707 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4709 /* When stepping backward, stop at beginning of line range
4710 (unless it's the function entry point, in which case
4711 keep going back to the call point). */
4712 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4713 && stop_pc
!= ecs
->stop_func_start
4714 && execution_direction
== EXEC_REVERSE
)
4716 ecs
->event_thread
->control
.stop_step
= 1;
4717 print_end_stepping_range_reason ();
4718 stop_stepping (ecs
);
4726 /* We stepped out of the stepping range. */
4728 /* If we are stepping at the source level and entered the runtime
4729 loader dynamic symbol resolution code...
4731 EXEC_FORWARD: we keep on single stepping until we exit the run
4732 time loader code and reach the callee's address.
4734 EXEC_REVERSE: we've already executed the callee (backward), and
4735 the runtime loader code is handled just like any other
4736 undebuggable function call. Now we need only keep stepping
4737 backward through the trampoline code, and that's handled further
4738 down, so there is nothing for us to do here. */
4740 if (execution_direction
!= EXEC_REVERSE
4741 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4742 && in_solib_dynsym_resolve_code (stop_pc
))
4744 CORE_ADDR pc_after_resolver
=
4745 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
4748 fprintf_unfiltered (gdb_stdlog
,
4749 "infrun: stepped into dynsym resolve code\n");
4751 if (pc_after_resolver
)
4753 /* Set up a step-resume breakpoint at the address
4754 indicated by SKIP_SOLIB_RESOLVER. */
4755 struct symtab_and_line sr_sal
;
4758 sr_sal
.pc
= pc_after_resolver
;
4759 sr_sal
.pspace
= get_frame_program_space (frame
);
4761 insert_step_resume_breakpoint_at_sal (gdbarch
,
4762 sr_sal
, null_frame_id
);
4769 if (ecs
->event_thread
->control
.step_range_end
!= 1
4770 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4771 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4772 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
4775 fprintf_unfiltered (gdb_stdlog
,
4776 "infrun: stepped into signal trampoline\n");
4777 /* The inferior, while doing a "step" or "next", has ended up in
4778 a signal trampoline (either by a signal being delivered or by
4779 the signal handler returning). Just single-step until the
4780 inferior leaves the trampoline (either by calling the handler
4786 /* If we're in the return path from a shared library trampoline,
4787 we want to proceed through the trampoline when stepping. */
4788 /* macro/2012-04-25: This needs to come before the subroutine
4789 call check below as on some targets return trampolines look
4790 like subroutine calls (MIPS16 return thunks). */
4791 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4792 stop_pc
, ecs
->stop_func_name
)
4793 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
4795 /* Determine where this trampoline returns. */
4796 CORE_ADDR real_stop_pc
;
4798 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4801 fprintf_unfiltered (gdb_stdlog
,
4802 "infrun: stepped into solib return tramp\n");
4804 /* Only proceed through if we know where it's going. */
4807 /* And put the step-breakpoint there and go until there. */
4808 struct symtab_and_line sr_sal
;
4810 init_sal (&sr_sal
); /* initialize to zeroes */
4811 sr_sal
.pc
= real_stop_pc
;
4812 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4813 sr_sal
.pspace
= get_frame_program_space (frame
);
4815 /* Do not specify what the fp should be when we stop since
4816 on some machines the prologue is where the new fp value
4818 insert_step_resume_breakpoint_at_sal (gdbarch
,
4819 sr_sal
, null_frame_id
);
4821 /* Restart without fiddling with the step ranges or
4828 /* Check for subroutine calls. The check for the current frame
4829 equalling the step ID is not necessary - the check of the
4830 previous frame's ID is sufficient - but it is a common case and
4831 cheaper than checking the previous frame's ID.
4833 NOTE: frame_id_eq will never report two invalid frame IDs as
4834 being equal, so to get into this block, both the current and
4835 previous frame must have valid frame IDs. */
4836 /* The outer_frame_id check is a heuristic to detect stepping
4837 through startup code. If we step over an instruction which
4838 sets the stack pointer from an invalid value to a valid value,
4839 we may detect that as a subroutine call from the mythical
4840 "outermost" function. This could be fixed by marking
4841 outermost frames as !stack_p,code_p,special_p. Then the
4842 initial outermost frame, before sp was valid, would
4843 have code_addr == &_start. See the comment in frame_id_eq
4845 if (!frame_id_eq (get_stack_frame_id (frame
),
4846 ecs
->event_thread
->control
.step_stack_frame_id
)
4847 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4848 ecs
->event_thread
->control
.step_stack_frame_id
)
4849 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
4851 || step_start_function
!= find_pc_function (stop_pc
))))
4853 CORE_ADDR real_stop_pc
;
4856 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
4858 if ((ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
4859 || ((ecs
->event_thread
->control
.step_range_end
== 1)
4860 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
4861 ecs
->stop_func_start
)))
4863 /* I presume that step_over_calls is only 0 when we're
4864 supposed to be stepping at the assembly language level
4865 ("stepi"). Just stop. */
4866 /* Also, maybe we just did a "nexti" inside a prolog, so we
4867 thought it was a subroutine call but it was not. Stop as
4869 /* And this works the same backward as frontward. MVS */
4870 ecs
->event_thread
->control
.stop_step
= 1;
4871 print_end_stepping_range_reason ();
4872 stop_stepping (ecs
);
4876 /* Reverse stepping through solib trampolines. */
4878 if (execution_direction
== EXEC_REVERSE
4879 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
4880 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4881 || (ecs
->stop_func_start
== 0
4882 && in_solib_dynsym_resolve_code (stop_pc
))))
4884 /* Any solib trampoline code can be handled in reverse
4885 by simply continuing to single-step. We have already
4886 executed the solib function (backwards), and a few
4887 steps will take us back through the trampoline to the
4893 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4895 /* We're doing a "next".
4897 Normal (forward) execution: set a breakpoint at the
4898 callee's return address (the address at which the caller
4901 Reverse (backward) execution. set the step-resume
4902 breakpoint at the start of the function that we just
4903 stepped into (backwards), and continue to there. When we
4904 get there, we'll need to single-step back to the caller. */
4906 if (execution_direction
== EXEC_REVERSE
)
4908 struct symtab_and_line sr_sal
;
4910 /* Normal function call return (static or dynamic). */
4912 sr_sal
.pc
= ecs
->stop_func_start
;
4913 sr_sal
.pspace
= get_frame_program_space (frame
);
4914 insert_step_resume_breakpoint_at_sal (gdbarch
,
4915 sr_sal
, null_frame_id
);
4918 insert_step_resume_breakpoint_at_caller (frame
);
4924 /* If we are in a function call trampoline (a stub between the
4925 calling routine and the real function), locate the real
4926 function. That's what tells us (a) whether we want to step
4927 into it at all, and (b) what prologue we want to run to the
4928 end of, if we do step into it. */
4929 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
4930 if (real_stop_pc
== 0)
4931 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4932 if (real_stop_pc
!= 0)
4933 ecs
->stop_func_start
= real_stop_pc
;
4935 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
4937 struct symtab_and_line sr_sal
;
4940 sr_sal
.pc
= ecs
->stop_func_start
;
4941 sr_sal
.pspace
= get_frame_program_space (frame
);
4943 insert_step_resume_breakpoint_at_sal (gdbarch
,
4944 sr_sal
, null_frame_id
);
4949 /* If we have line number information for the function we are
4950 thinking of stepping into and the function isn't on the skip
4953 If there are several symtabs at that PC (e.g. with include
4954 files), just want to know whether *any* of them have line
4955 numbers. find_pc_line handles this. */
4957 struct symtab_and_line tmp_sal
;
4959 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4960 if (tmp_sal
.line
!= 0
4961 && !function_pc_is_marked_for_skip (ecs
->stop_func_start
))
4963 if (execution_direction
== EXEC_REVERSE
)
4964 handle_step_into_function_backward (gdbarch
, ecs
);
4966 handle_step_into_function (gdbarch
, ecs
);
4971 /* If we have no line number and the step-stop-if-no-debug is
4972 set, we stop the step so that the user has a chance to switch
4973 in assembly mode. */
4974 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4975 && step_stop_if_no_debug
)
4977 ecs
->event_thread
->control
.stop_step
= 1;
4978 print_end_stepping_range_reason ();
4979 stop_stepping (ecs
);
4983 if (execution_direction
== EXEC_REVERSE
)
4985 /* Set a breakpoint at callee's start address.
4986 From there we can step once and be back in the caller. */
4987 struct symtab_and_line sr_sal
;
4990 sr_sal
.pc
= ecs
->stop_func_start
;
4991 sr_sal
.pspace
= get_frame_program_space (frame
);
4992 insert_step_resume_breakpoint_at_sal (gdbarch
,
4993 sr_sal
, null_frame_id
);
4996 /* Set a breakpoint at callee's return address (the address
4997 at which the caller will resume). */
4998 insert_step_resume_breakpoint_at_caller (frame
);
5004 /* Reverse stepping through solib trampolines. */
5006 if (execution_direction
== EXEC_REVERSE
5007 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5009 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5010 || (ecs
->stop_func_start
== 0
5011 && in_solib_dynsym_resolve_code (stop_pc
)))
5013 /* Any solib trampoline code can be handled in reverse
5014 by simply continuing to single-step. We have already
5015 executed the solib function (backwards), and a few
5016 steps will take us back through the trampoline to the
5021 else if (in_solib_dynsym_resolve_code (stop_pc
))
5023 /* Stepped backward into the solib dynsym resolver.
5024 Set a breakpoint at its start and continue, then
5025 one more step will take us out. */
5026 struct symtab_and_line sr_sal
;
5029 sr_sal
.pc
= ecs
->stop_func_start
;
5030 sr_sal
.pspace
= get_frame_program_space (frame
);
5031 insert_step_resume_breakpoint_at_sal (gdbarch
,
5032 sr_sal
, null_frame_id
);
5038 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5040 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5041 the trampoline processing logic, however, there are some trampolines
5042 that have no names, so we should do trampoline handling first. */
5043 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5044 && ecs
->stop_func_name
== NULL
5045 && stop_pc_sal
.line
== 0)
5048 fprintf_unfiltered (gdb_stdlog
,
5049 "infrun: stepped into undebuggable function\n");
5051 /* The inferior just stepped into, or returned to, an
5052 undebuggable function (where there is no debugging information
5053 and no line number corresponding to the address where the
5054 inferior stopped). Since we want to skip this kind of code,
5055 we keep going until the inferior returns from this
5056 function - unless the user has asked us not to (via
5057 set step-mode) or we no longer know how to get back
5058 to the call site. */
5059 if (step_stop_if_no_debug
5060 || !frame_id_p (frame_unwind_caller_id (frame
)))
5062 /* If we have no line number and the step-stop-if-no-debug
5063 is set, we stop the step so that the user has a chance to
5064 switch in assembly mode. */
5065 ecs
->event_thread
->control
.stop_step
= 1;
5066 print_end_stepping_range_reason ();
5067 stop_stepping (ecs
);
5072 /* Set a breakpoint at callee's return address (the address
5073 at which the caller will resume). */
5074 insert_step_resume_breakpoint_at_caller (frame
);
5080 if (ecs
->event_thread
->control
.step_range_end
== 1)
5082 /* It is stepi or nexti. We always want to stop stepping after
5085 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5086 ecs
->event_thread
->control
.stop_step
= 1;
5087 print_end_stepping_range_reason ();
5088 stop_stepping (ecs
);
5092 if (stop_pc_sal
.line
== 0)
5094 /* We have no line number information. That means to stop
5095 stepping (does this always happen right after one instruction,
5096 when we do "s" in a function with no line numbers,
5097 or can this happen as a result of a return or longjmp?). */
5099 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5100 ecs
->event_thread
->control
.stop_step
= 1;
5101 print_end_stepping_range_reason ();
5102 stop_stepping (ecs
);
5106 /* Look for "calls" to inlined functions, part one. If the inline
5107 frame machinery detected some skipped call sites, we have entered
5108 a new inline function. */
5110 if (frame_id_eq (get_frame_id (get_current_frame ()),
5111 ecs
->event_thread
->control
.step_frame_id
)
5112 && inline_skipped_frames (ecs
->ptid
))
5114 struct symtab_and_line call_sal
;
5117 fprintf_unfiltered (gdb_stdlog
,
5118 "infrun: stepped into inlined function\n");
5120 find_frame_sal (get_current_frame (), &call_sal
);
5122 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5124 /* For "step", we're going to stop. But if the call site
5125 for this inlined function is on the same source line as
5126 we were previously stepping, go down into the function
5127 first. Otherwise stop at the call site. */
5129 if (call_sal
.line
== ecs
->event_thread
->current_line
5130 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5131 step_into_inline_frame (ecs
->ptid
);
5133 ecs
->event_thread
->control
.stop_step
= 1;
5134 print_end_stepping_range_reason ();
5135 stop_stepping (ecs
);
5140 /* For "next", we should stop at the call site if it is on a
5141 different source line. Otherwise continue through the
5142 inlined function. */
5143 if (call_sal
.line
== ecs
->event_thread
->current_line
5144 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5148 ecs
->event_thread
->control
.stop_step
= 1;
5149 print_end_stepping_range_reason ();
5150 stop_stepping (ecs
);
5156 /* Look for "calls" to inlined functions, part two. If we are still
5157 in the same real function we were stepping through, but we have
5158 to go further up to find the exact frame ID, we are stepping
5159 through a more inlined call beyond its call site. */
5161 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5162 && !frame_id_eq (get_frame_id (get_current_frame ()),
5163 ecs
->event_thread
->control
.step_frame_id
)
5164 && stepped_in_from (get_current_frame (),
5165 ecs
->event_thread
->control
.step_frame_id
))
5168 fprintf_unfiltered (gdb_stdlog
,
5169 "infrun: stepping through inlined function\n");
5171 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5175 ecs
->event_thread
->control
.stop_step
= 1;
5176 print_end_stepping_range_reason ();
5177 stop_stepping (ecs
);
5182 if ((stop_pc
== stop_pc_sal
.pc
)
5183 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5184 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5186 /* We are at the start of a different line. So stop. Note that
5187 we don't stop if we step into the middle of a different line.
5188 That is said to make things like for (;;) statements work
5191 fprintf_unfiltered (gdb_stdlog
,
5192 "infrun: stepped to a different line\n");
5193 ecs
->event_thread
->control
.stop_step
= 1;
5194 print_end_stepping_range_reason ();
5195 stop_stepping (ecs
);
5199 /* We aren't done stepping.
5201 Optimize by setting the stepping range to the line.
5202 (We might not be in the original line, but if we entered a
5203 new line in mid-statement, we continue stepping. This makes
5204 things like for(;;) statements work better.) */
5206 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5207 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5208 set_step_info (frame
, stop_pc_sal
);
5211 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5215 /* Is thread TP in the middle of single-stepping? */
5218 currently_stepping (struct thread_info
*tp
)
5220 return ((tp
->control
.step_range_end
5221 && tp
->control
.step_resume_breakpoint
== NULL
)
5222 || tp
->control
.trap_expected
5223 || bpstat_should_step ());
5226 /* Returns true if any thread *but* the one passed in "data" is in the
5227 middle of stepping or of handling a "next". */
5230 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
5235 return (tp
->control
.step_range_end
5236 || tp
->control
.trap_expected
);
5239 /* Inferior has stepped into a subroutine call with source code that
5240 we should not step over. Do step to the first line of code in
5244 handle_step_into_function (struct gdbarch
*gdbarch
,
5245 struct execution_control_state
*ecs
)
5248 struct symtab_and_line stop_func_sal
, sr_sal
;
5250 fill_in_stop_func (gdbarch
, ecs
);
5252 s
= find_pc_symtab (stop_pc
);
5253 if (s
&& s
->language
!= language_asm
)
5254 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5255 ecs
->stop_func_start
);
5257 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5258 /* Use the step_resume_break to step until the end of the prologue,
5259 even if that involves jumps (as it seems to on the vax under
5261 /* If the prologue ends in the middle of a source line, continue to
5262 the end of that source line (if it is still within the function).
5263 Otherwise, just go to end of prologue. */
5264 if (stop_func_sal
.end
5265 && stop_func_sal
.pc
!= ecs
->stop_func_start
5266 && stop_func_sal
.end
< ecs
->stop_func_end
)
5267 ecs
->stop_func_start
= stop_func_sal
.end
;
5269 /* Architectures which require breakpoint adjustment might not be able
5270 to place a breakpoint at the computed address. If so, the test
5271 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5272 ecs->stop_func_start to an address at which a breakpoint may be
5273 legitimately placed.
5275 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5276 made, GDB will enter an infinite loop when stepping through
5277 optimized code consisting of VLIW instructions which contain
5278 subinstructions corresponding to different source lines. On
5279 FR-V, it's not permitted to place a breakpoint on any but the
5280 first subinstruction of a VLIW instruction. When a breakpoint is
5281 set, GDB will adjust the breakpoint address to the beginning of
5282 the VLIW instruction. Thus, we need to make the corresponding
5283 adjustment here when computing the stop address. */
5285 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5287 ecs
->stop_func_start
5288 = gdbarch_adjust_breakpoint_address (gdbarch
,
5289 ecs
->stop_func_start
);
5292 if (ecs
->stop_func_start
== stop_pc
)
5294 /* We are already there: stop now. */
5295 ecs
->event_thread
->control
.stop_step
= 1;
5296 print_end_stepping_range_reason ();
5297 stop_stepping (ecs
);
5302 /* Put the step-breakpoint there and go until there. */
5303 init_sal (&sr_sal
); /* initialize to zeroes */
5304 sr_sal
.pc
= ecs
->stop_func_start
;
5305 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5306 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5308 /* Do not specify what the fp should be when we stop since on
5309 some machines the prologue is where the new fp value is
5311 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5313 /* And make sure stepping stops right away then. */
5314 ecs
->event_thread
->control
.step_range_end
5315 = ecs
->event_thread
->control
.step_range_start
;
5320 /* Inferior has stepped backward into a subroutine call with source
5321 code that we should not step over. Do step to the beginning of the
5322 last line of code in it. */
5325 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5326 struct execution_control_state
*ecs
)
5329 struct symtab_and_line stop_func_sal
;
5331 fill_in_stop_func (gdbarch
, ecs
);
5333 s
= find_pc_symtab (stop_pc
);
5334 if (s
&& s
->language
!= language_asm
)
5335 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5336 ecs
->stop_func_start
);
5338 stop_func_sal
= find_pc_line (stop_pc
, 0);
5340 /* OK, we're just going to keep stepping here. */
5341 if (stop_func_sal
.pc
== stop_pc
)
5343 /* We're there already. Just stop stepping now. */
5344 ecs
->event_thread
->control
.stop_step
= 1;
5345 print_end_stepping_range_reason ();
5346 stop_stepping (ecs
);
5350 /* Else just reset the step range and keep going.
5351 No step-resume breakpoint, they don't work for
5352 epilogues, which can have multiple entry paths. */
5353 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5354 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5360 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5361 This is used to both functions and to skip over code. */
5364 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5365 struct symtab_and_line sr_sal
,
5366 struct frame_id sr_id
,
5367 enum bptype sr_type
)
5369 /* There should never be more than one step-resume or longjmp-resume
5370 breakpoint per thread, so we should never be setting a new
5371 step_resume_breakpoint when one is already active. */
5372 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5373 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5376 fprintf_unfiltered (gdb_stdlog
,
5377 "infrun: inserting step-resume breakpoint at %s\n",
5378 paddress (gdbarch
, sr_sal
.pc
));
5380 inferior_thread ()->control
.step_resume_breakpoint
5381 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5385 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5386 struct symtab_and_line sr_sal
,
5387 struct frame_id sr_id
)
5389 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5394 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5395 This is used to skip a potential signal handler.
5397 This is called with the interrupted function's frame. The signal
5398 handler, when it returns, will resume the interrupted function at
5402 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5404 struct symtab_and_line sr_sal
;
5405 struct gdbarch
*gdbarch
;
5407 gdb_assert (return_frame
!= NULL
);
5408 init_sal (&sr_sal
); /* initialize to zeros */
5410 gdbarch
= get_frame_arch (return_frame
);
5411 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5412 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5413 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5415 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5416 get_stack_frame_id (return_frame
),
5420 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5421 is used to skip a function after stepping into it (for "next" or if
5422 the called function has no debugging information).
5424 The current function has almost always been reached by single
5425 stepping a call or return instruction. NEXT_FRAME belongs to the
5426 current function, and the breakpoint will be set at the caller's
5429 This is a separate function rather than reusing
5430 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5431 get_prev_frame, which may stop prematurely (see the implementation
5432 of frame_unwind_caller_id for an example). */
5435 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5437 struct symtab_and_line sr_sal
;
5438 struct gdbarch
*gdbarch
;
5440 /* We shouldn't have gotten here if we don't know where the call site
5442 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5444 init_sal (&sr_sal
); /* initialize to zeros */
5446 gdbarch
= frame_unwind_caller_arch (next_frame
);
5447 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5448 frame_unwind_caller_pc (next_frame
));
5449 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5450 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5452 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5453 frame_unwind_caller_id (next_frame
));
5456 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5457 new breakpoint at the target of a jmp_buf. The handling of
5458 longjmp-resume uses the same mechanisms used for handling
5459 "step-resume" breakpoints. */
5462 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5464 /* There should never be more than one longjmp-resume breakpoint per
5465 thread, so we should never be setting a new
5466 longjmp_resume_breakpoint when one is already active. */
5467 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
5470 fprintf_unfiltered (gdb_stdlog
,
5471 "infrun: inserting longjmp-resume breakpoint at %s\n",
5472 paddress (gdbarch
, pc
));
5474 inferior_thread ()->control
.exception_resume_breakpoint
=
5475 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5478 /* Insert an exception resume breakpoint. TP is the thread throwing
5479 the exception. The block B is the block of the unwinder debug hook
5480 function. FRAME is the frame corresponding to the call to this
5481 function. SYM is the symbol of the function argument holding the
5482 target PC of the exception. */
5485 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5487 struct frame_info
*frame
,
5490 volatile struct gdb_exception e
;
5492 /* We want to ignore errors here. */
5493 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5495 struct symbol
*vsym
;
5496 struct value
*value
;
5498 struct breakpoint
*bp
;
5500 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5501 value
= read_var_value (vsym
, frame
);
5502 /* If the value was optimized out, revert to the old behavior. */
5503 if (! value_optimized_out (value
))
5505 handler
= value_as_address (value
);
5508 fprintf_unfiltered (gdb_stdlog
,
5509 "infrun: exception resume at %lx\n",
5510 (unsigned long) handler
);
5512 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5513 handler
, bp_exception_resume
);
5515 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5518 bp
->thread
= tp
->num
;
5519 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5524 /* A helper for check_exception_resume that sets an
5525 exception-breakpoint based on a SystemTap probe. */
5528 insert_exception_resume_from_probe (struct thread_info
*tp
,
5529 const struct probe
*probe
,
5530 struct frame_info
*frame
)
5532 struct value
*arg_value
;
5534 struct breakpoint
*bp
;
5536 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
5540 handler
= value_as_address (arg_value
);
5543 fprintf_unfiltered (gdb_stdlog
,
5544 "infrun: exception resume at %s\n",
5545 paddress (get_objfile_arch (probe
->objfile
),
5548 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5549 handler
, bp_exception_resume
);
5550 bp
->thread
= tp
->num
;
5551 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5554 /* This is called when an exception has been intercepted. Check to
5555 see whether the exception's destination is of interest, and if so,
5556 set an exception resume breakpoint there. */
5559 check_exception_resume (struct execution_control_state
*ecs
,
5560 struct frame_info
*frame
)
5562 volatile struct gdb_exception e
;
5563 const struct probe
*probe
;
5564 struct symbol
*func
;
5566 /* First see if this exception unwinding breakpoint was set via a
5567 SystemTap probe point. If so, the probe has two arguments: the
5568 CFA and the HANDLER. We ignore the CFA, extract the handler, and
5569 set a breakpoint there. */
5570 probe
= find_probe_by_pc (get_frame_pc (frame
));
5573 insert_exception_resume_from_probe (ecs
->event_thread
, probe
, frame
);
5577 func
= get_frame_function (frame
);
5581 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5584 struct block_iterator iter
;
5588 /* The exception breakpoint is a thread-specific breakpoint on
5589 the unwinder's debug hook, declared as:
5591 void _Unwind_DebugHook (void *cfa, void *handler);
5593 The CFA argument indicates the frame to which control is
5594 about to be transferred. HANDLER is the destination PC.
5596 We ignore the CFA and set a temporary breakpoint at HANDLER.
5597 This is not extremely efficient but it avoids issues in gdb
5598 with computing the DWARF CFA, and it also works even in weird
5599 cases such as throwing an exception from inside a signal
5602 b
= SYMBOL_BLOCK_VALUE (func
);
5603 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
5605 if (!SYMBOL_IS_ARGUMENT (sym
))
5612 insert_exception_resume_breakpoint (ecs
->event_thread
,
5621 stop_stepping (struct execution_control_state
*ecs
)
5624 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
5626 /* Let callers know we don't want to wait for the inferior anymore. */
5627 ecs
->wait_some_more
= 0;
5630 /* This function handles various cases where we need to continue
5631 waiting for the inferior. */
5632 /* (Used to be the keep_going: label in the old wait_for_inferior). */
5635 keep_going (struct execution_control_state
*ecs
)
5637 /* Make sure normal_stop is called if we get a QUIT handled before
5639 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
5641 /* Save the pc before execution, to compare with pc after stop. */
5642 ecs
->event_thread
->prev_pc
5643 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5645 /* If we did not do break;, it means we should keep running the
5646 inferior and not return to debugger. */
5648 if (ecs
->event_thread
->control
.trap_expected
5649 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5651 /* We took a signal (which we are supposed to pass through to
5652 the inferior, else we'd not get here) and we haven't yet
5653 gotten our trap. Simply continue. */
5655 discard_cleanups (old_cleanups
);
5656 resume (currently_stepping (ecs
->event_thread
),
5657 ecs
->event_thread
->suspend
.stop_signal
);
5661 /* Either the trap was not expected, but we are continuing
5662 anyway (the user asked that this signal be passed to the
5665 The signal was SIGTRAP, e.g. it was our signal, but we
5666 decided we should resume from it.
5668 We're going to run this baby now!
5670 Note that insert_breakpoints won't try to re-insert
5671 already inserted breakpoints. Therefore, we don't
5672 care if breakpoints were already inserted, or not. */
5674 if (ecs
->event_thread
->stepping_over_breakpoint
)
5676 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
5678 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
5679 /* Since we can't do a displaced step, we have to remove
5680 the breakpoint while we step it. To keep things
5681 simple, we remove them all. */
5682 remove_breakpoints ();
5686 volatile struct gdb_exception e
;
5688 /* Stop stepping when inserting breakpoints
5690 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5692 insert_breakpoints ();
5696 exception_print (gdb_stderr
, e
);
5697 stop_stepping (ecs
);
5702 ecs
->event_thread
->control
.trap_expected
5703 = ecs
->event_thread
->stepping_over_breakpoint
;
5705 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
5706 specifies that such a signal should be delivered to the
5709 Typically, this would occure when a user is debugging a
5710 target monitor on a simulator: the target monitor sets a
5711 breakpoint; the simulator encounters this break-point and
5712 halts the simulation handing control to GDB; GDB, noteing
5713 that the break-point isn't valid, returns control back to the
5714 simulator; the simulator then delivers the hardware
5715 equivalent of a SIGNAL_TRAP to the program being debugged. */
5717 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5718 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5719 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5721 discard_cleanups (old_cleanups
);
5722 resume (currently_stepping (ecs
->event_thread
),
5723 ecs
->event_thread
->suspend
.stop_signal
);
5726 prepare_to_wait (ecs
);
5729 /* This function normally comes after a resume, before
5730 handle_inferior_event exits. It takes care of any last bits of
5731 housekeeping, and sets the all-important wait_some_more flag. */
5734 prepare_to_wait (struct execution_control_state
*ecs
)
5737 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
5739 /* This is the old end of the while loop. Let everybody know we
5740 want to wait for the inferior some more and get called again
5742 ecs
->wait_some_more
= 1;
5745 /* Several print_*_reason functions to print why the inferior has stopped.
5746 We always print something when the inferior exits, or receives a signal.
5747 The rest of the cases are dealt with later on in normal_stop and
5748 print_it_typical. Ideally there should be a call to one of these
5749 print_*_reason functions functions from handle_inferior_event each time
5750 stop_stepping is called. */
5752 /* Print why the inferior has stopped.
5753 We are done with a step/next/si/ni command, print why the inferior has
5754 stopped. For now print nothing. Print a message only if not in the middle
5755 of doing a "step n" operation for n > 1. */
5758 print_end_stepping_range_reason (void)
5760 if ((!inferior_thread ()->step_multi
5761 || !inferior_thread ()->control
.stop_step
)
5762 && ui_out_is_mi_like_p (current_uiout
))
5763 ui_out_field_string (current_uiout
, "reason",
5764 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
5767 /* The inferior was terminated by a signal, print why it stopped. */
5770 print_signal_exited_reason (enum gdb_signal siggnal
)
5772 struct ui_out
*uiout
= current_uiout
;
5774 annotate_signalled ();
5775 if (ui_out_is_mi_like_p (uiout
))
5777 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
5778 ui_out_text (uiout
, "\nProgram terminated with signal ");
5779 annotate_signal_name ();
5780 ui_out_field_string (uiout
, "signal-name",
5781 gdb_signal_to_name (siggnal
));
5782 annotate_signal_name_end ();
5783 ui_out_text (uiout
, ", ");
5784 annotate_signal_string ();
5785 ui_out_field_string (uiout
, "signal-meaning",
5786 gdb_signal_to_string (siggnal
));
5787 annotate_signal_string_end ();
5788 ui_out_text (uiout
, ".\n");
5789 ui_out_text (uiout
, "The program no longer exists.\n");
5792 /* The inferior program is finished, print why it stopped. */
5795 print_exited_reason (int exitstatus
)
5797 struct inferior
*inf
= current_inferior ();
5798 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
5799 struct ui_out
*uiout
= current_uiout
;
5801 annotate_exited (exitstatus
);
5804 if (ui_out_is_mi_like_p (uiout
))
5805 ui_out_field_string (uiout
, "reason",
5806 async_reason_lookup (EXEC_ASYNC_EXITED
));
5807 ui_out_text (uiout
, "[Inferior ");
5808 ui_out_text (uiout
, plongest (inf
->num
));
5809 ui_out_text (uiout
, " (");
5810 ui_out_text (uiout
, pidstr
);
5811 ui_out_text (uiout
, ") exited with code ");
5812 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
5813 ui_out_text (uiout
, "]\n");
5817 if (ui_out_is_mi_like_p (uiout
))
5819 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
5820 ui_out_text (uiout
, "[Inferior ");
5821 ui_out_text (uiout
, plongest (inf
->num
));
5822 ui_out_text (uiout
, " (");
5823 ui_out_text (uiout
, pidstr
);
5824 ui_out_text (uiout
, ") exited normally]\n");
5826 /* Support the --return-child-result option. */
5827 return_child_result_value
= exitstatus
;
5830 /* Signal received, print why the inferior has stopped. The signal table
5831 tells us to print about it. */
5834 print_signal_received_reason (enum gdb_signal siggnal
)
5836 struct ui_out
*uiout
= current_uiout
;
5840 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
5842 struct thread_info
*t
= inferior_thread ();
5844 ui_out_text (uiout
, "\n[");
5845 ui_out_field_string (uiout
, "thread-name",
5846 target_pid_to_str (t
->ptid
));
5847 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
5848 ui_out_text (uiout
, " stopped");
5852 ui_out_text (uiout
, "\nProgram received signal ");
5853 annotate_signal_name ();
5854 if (ui_out_is_mi_like_p (uiout
))
5856 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
5857 ui_out_field_string (uiout
, "signal-name",
5858 gdb_signal_to_name (siggnal
));
5859 annotate_signal_name_end ();
5860 ui_out_text (uiout
, ", ");
5861 annotate_signal_string ();
5862 ui_out_field_string (uiout
, "signal-meaning",
5863 gdb_signal_to_string (siggnal
));
5864 annotate_signal_string_end ();
5866 ui_out_text (uiout
, ".\n");
5869 /* Reverse execution: target ran out of history info, print why the inferior
5873 print_no_history_reason (void)
5875 ui_out_text (current_uiout
, "\nNo more reverse-execution history.\n");
5878 /* Here to return control to GDB when the inferior stops for real.
5879 Print appropriate messages, remove breakpoints, give terminal our modes.
5881 STOP_PRINT_FRAME nonzero means print the executing frame
5882 (pc, function, args, file, line number and line text).
5883 BREAKPOINTS_FAILED nonzero means stop was due to error
5884 attempting to insert breakpoints. */
5889 struct target_waitstatus last
;
5891 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
5893 get_last_target_status (&last_ptid
, &last
);
5895 /* If an exception is thrown from this point on, make sure to
5896 propagate GDB's knowledge of the executing state to the
5897 frontend/user running state. A QUIT is an easy exception to see
5898 here, so do this before any filtered output. */
5900 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
5901 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
5902 && last
.kind
!= TARGET_WAITKIND_EXITED
5903 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
5904 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
5906 /* In non-stop mode, we don't want GDB to switch threads behind the
5907 user's back, to avoid races where the user is typing a command to
5908 apply to thread x, but GDB switches to thread y before the user
5909 finishes entering the command. */
5911 /* As with the notification of thread events, we want to delay
5912 notifying the user that we've switched thread context until
5913 the inferior actually stops.
5915 There's no point in saying anything if the inferior has exited.
5916 Note that SIGNALLED here means "exited with a signal", not
5917 "received a signal". */
5919 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
5920 && target_has_execution
5921 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5922 && last
.kind
!= TARGET_WAITKIND_EXITED
5923 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
5925 target_terminal_ours_for_output ();
5926 printf_filtered (_("[Switching to %s]\n"),
5927 target_pid_to_str (inferior_ptid
));
5928 annotate_thread_changed ();
5929 previous_inferior_ptid
= inferior_ptid
;
5932 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
5934 gdb_assert (sync_execution
|| !target_can_async_p ());
5936 target_terminal_ours_for_output ();
5937 printf_filtered (_("No unwaited-for children left.\n"));
5940 if (!breakpoints_always_inserted_mode () && target_has_execution
)
5942 if (remove_breakpoints ())
5944 target_terminal_ours_for_output ();
5945 printf_filtered (_("Cannot remove breakpoints because "
5946 "program is no longer writable.\nFurther "
5947 "execution is probably impossible.\n"));
5951 /* If an auto-display called a function and that got a signal,
5952 delete that auto-display to avoid an infinite recursion. */
5954 if (stopped_by_random_signal
)
5955 disable_current_display ();
5957 /* Don't print a message if in the middle of doing a "step n"
5958 operation for n > 1 */
5959 if (target_has_execution
5960 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5961 && last
.kind
!= TARGET_WAITKIND_EXITED
5962 && inferior_thread ()->step_multi
5963 && inferior_thread ()->control
.stop_step
)
5966 target_terminal_ours ();
5967 async_enable_stdin ();
5969 /* Set the current source location. This will also happen if we
5970 display the frame below, but the current SAL will be incorrect
5971 during a user hook-stop function. */
5972 if (has_stack_frames () && !stop_stack_dummy
)
5973 set_current_sal_from_frame (get_current_frame (), 1);
5975 /* Let the user/frontend see the threads as stopped. */
5976 do_cleanups (old_chain
);
5978 /* Look up the hook_stop and run it (CLI internally handles problem
5979 of stop_command's pre-hook not existing). */
5981 catch_errors (hook_stop_stub
, stop_command
,
5982 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
5984 if (!has_stack_frames ())
5987 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
5988 || last
.kind
== TARGET_WAITKIND_EXITED
)
5991 /* Select innermost stack frame - i.e., current frame is frame 0,
5992 and current location is based on that.
5993 Don't do this on return from a stack dummy routine,
5994 or if the program has exited. */
5996 if (!stop_stack_dummy
)
5998 select_frame (get_current_frame ());
6000 /* Print current location without a level number, if
6001 we have changed functions or hit a breakpoint.
6002 Print source line if we have one.
6003 bpstat_print() contains the logic deciding in detail
6004 what to print, based on the event(s) that just occurred. */
6006 /* If --batch-silent is enabled then there's no need to print the current
6007 source location, and to try risks causing an error message about
6008 missing source files. */
6009 if (stop_print_frame
&& !batch_silent
)
6013 int do_frame_printing
= 1;
6014 struct thread_info
*tp
= inferior_thread ();
6016 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, last
.kind
);
6020 /* FIXME: cagney/2002-12-01: Given that a frame ID does
6021 (or should) carry around the function and does (or
6022 should) use that when doing a frame comparison. */
6023 if (tp
->control
.stop_step
6024 && frame_id_eq (tp
->control
.step_frame_id
,
6025 get_frame_id (get_current_frame ()))
6026 && step_start_function
== find_pc_function (stop_pc
))
6027 source_flag
= SRC_LINE
; /* Finished step, just
6028 print source line. */
6030 source_flag
= SRC_AND_LOC
; /* Print location and
6033 case PRINT_SRC_AND_LOC
:
6034 source_flag
= SRC_AND_LOC
; /* Print location and
6037 case PRINT_SRC_ONLY
:
6038 source_flag
= SRC_LINE
;
6041 source_flag
= SRC_LINE
; /* something bogus */
6042 do_frame_printing
= 0;
6045 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6048 /* The behavior of this routine with respect to the source
6050 SRC_LINE: Print only source line
6051 LOCATION: Print only location
6052 SRC_AND_LOC: Print location and source line. */
6053 if (do_frame_printing
)
6054 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
6056 /* Display the auto-display expressions. */
6061 /* Save the function value return registers, if we care.
6062 We might be about to restore their previous contents. */
6063 if (inferior_thread ()->control
.proceed_to_finish
6064 && execution_direction
!= EXEC_REVERSE
)
6066 /* This should not be necessary. */
6068 regcache_xfree (stop_registers
);
6070 /* NB: The copy goes through to the target picking up the value of
6071 all the registers. */
6072 stop_registers
= regcache_dup (get_current_regcache ());
6075 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6077 /* Pop the empty frame that contains the stack dummy.
6078 This also restores inferior state prior to the call
6079 (struct infcall_suspend_state). */
6080 struct frame_info
*frame
= get_current_frame ();
6082 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6084 /* frame_pop() calls reinit_frame_cache as the last thing it
6085 does which means there's currently no selected frame. We
6086 don't need to re-establish a selected frame if the dummy call
6087 returns normally, that will be done by
6088 restore_infcall_control_state. However, we do have to handle
6089 the case where the dummy call is returning after being
6090 stopped (e.g. the dummy call previously hit a breakpoint).
6091 We can't know which case we have so just always re-establish
6092 a selected frame here. */
6093 select_frame (get_current_frame ());
6097 annotate_stopped ();
6099 /* Suppress the stop observer if we're in the middle of:
6101 - a step n (n > 1), as there still more steps to be done.
6103 - a "finish" command, as the observer will be called in
6104 finish_command_continuation, so it can include the inferior
6105 function's return value.
6107 - calling an inferior function, as we pretend we inferior didn't
6108 run at all. The return value of the call is handled by the
6109 expression evaluator, through call_function_by_hand. */
6111 if (!target_has_execution
6112 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6113 || last
.kind
== TARGET_WAITKIND_EXITED
6114 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6115 || (!(inferior_thread ()->step_multi
6116 && inferior_thread ()->control
.stop_step
)
6117 && !(inferior_thread ()->control
.stop_bpstat
6118 && inferior_thread ()->control
.proceed_to_finish
)
6119 && !inferior_thread ()->control
.in_infcall
))
6121 if (!ptid_equal (inferior_ptid
, null_ptid
))
6122 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6125 observer_notify_normal_stop (NULL
, stop_print_frame
);
6128 if (target_has_execution
)
6130 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6131 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6132 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6133 Delete any breakpoint that is to be deleted at the next stop. */
6134 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6137 /* Try to get rid of automatically added inferiors that are no
6138 longer needed. Keeping those around slows down things linearly.
6139 Note that this never removes the current inferior. */
6144 hook_stop_stub (void *cmd
)
6146 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6151 signal_stop_state (int signo
)
6153 return signal_stop
[signo
];
6157 signal_print_state (int signo
)
6159 return signal_print
[signo
];
6163 signal_pass_state (int signo
)
6165 return signal_program
[signo
];
6169 signal_cache_update (int signo
)
6173 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6174 signal_cache_update (signo
);
6179 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6180 && signal_print
[signo
] == 0
6181 && signal_program
[signo
] == 1);
6185 signal_stop_update (int signo
, int state
)
6187 int ret
= signal_stop
[signo
];
6189 signal_stop
[signo
] = state
;
6190 signal_cache_update (signo
);
6195 signal_print_update (int signo
, int state
)
6197 int ret
= signal_print
[signo
];
6199 signal_print
[signo
] = state
;
6200 signal_cache_update (signo
);
6205 signal_pass_update (int signo
, int state
)
6207 int ret
= signal_program
[signo
];
6209 signal_program
[signo
] = state
;
6210 signal_cache_update (signo
);
6215 sig_print_header (void)
6217 printf_filtered (_("Signal Stop\tPrint\tPass "
6218 "to program\tDescription\n"));
6222 sig_print_info (enum gdb_signal oursig
)
6224 const char *name
= gdb_signal_to_name (oursig
);
6225 int name_padding
= 13 - strlen (name
);
6227 if (name_padding
<= 0)
6230 printf_filtered ("%s", name
);
6231 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6232 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6233 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6234 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6235 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6238 /* Specify how various signals in the inferior should be handled. */
6241 handle_command (char *args
, int from_tty
)
6244 int digits
, wordlen
;
6245 int sigfirst
, signum
, siglast
;
6246 enum gdb_signal oursig
;
6249 unsigned char *sigs
;
6250 struct cleanup
*old_chain
;
6254 error_no_arg (_("signal to handle"));
6257 /* Allocate and zero an array of flags for which signals to handle. */
6259 nsigs
= (int) GDB_SIGNAL_LAST
;
6260 sigs
= (unsigned char *) alloca (nsigs
);
6261 memset (sigs
, 0, nsigs
);
6263 /* Break the command line up into args. */
6265 argv
= gdb_buildargv (args
);
6266 old_chain
= make_cleanup_freeargv (argv
);
6268 /* Walk through the args, looking for signal oursigs, signal names, and
6269 actions. Signal numbers and signal names may be interspersed with
6270 actions, with the actions being performed for all signals cumulatively
6271 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6273 while (*argv
!= NULL
)
6275 wordlen
= strlen (*argv
);
6276 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6280 sigfirst
= siglast
= -1;
6282 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6284 /* Apply action to all signals except those used by the
6285 debugger. Silently skip those. */
6288 siglast
= nsigs
- 1;
6290 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6292 SET_SIGS (nsigs
, sigs
, signal_stop
);
6293 SET_SIGS (nsigs
, sigs
, signal_print
);
6295 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6297 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6299 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6301 SET_SIGS (nsigs
, sigs
, signal_print
);
6303 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6305 SET_SIGS (nsigs
, sigs
, signal_program
);
6307 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6309 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6311 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6313 SET_SIGS (nsigs
, sigs
, signal_program
);
6315 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6317 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6318 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6320 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6322 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6324 else if (digits
> 0)
6326 /* It is numeric. The numeric signal refers to our own
6327 internal signal numbering from target.h, not to host/target
6328 signal number. This is a feature; users really should be
6329 using symbolic names anyway, and the common ones like
6330 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6332 sigfirst
= siglast
= (int)
6333 gdb_signal_from_command (atoi (*argv
));
6334 if ((*argv
)[digits
] == '-')
6337 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6339 if (sigfirst
> siglast
)
6341 /* Bet he didn't figure we'd think of this case... */
6349 oursig
= gdb_signal_from_name (*argv
);
6350 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
6352 sigfirst
= siglast
= (int) oursig
;
6356 /* Not a number and not a recognized flag word => complain. */
6357 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6361 /* If any signal numbers or symbol names were found, set flags for
6362 which signals to apply actions to. */
6364 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6366 switch ((enum gdb_signal
) signum
)
6368 case GDB_SIGNAL_TRAP
:
6369 case GDB_SIGNAL_INT
:
6370 if (!allsigs
&& !sigs
[signum
])
6372 if (query (_("%s is used by the debugger.\n\
6373 Are you sure you want to change it? "),
6374 gdb_signal_to_name ((enum gdb_signal
) signum
)))
6380 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6381 gdb_flush (gdb_stdout
);
6386 case GDB_SIGNAL_DEFAULT
:
6387 case GDB_SIGNAL_UNKNOWN
:
6388 /* Make sure that "all" doesn't print these. */
6399 for (signum
= 0; signum
< nsigs
; signum
++)
6402 signal_cache_update (-1);
6403 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6404 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
6408 /* Show the results. */
6409 sig_print_header ();
6410 for (; signum
< nsigs
; signum
++)
6412 sig_print_info (signum
);
6418 do_cleanups (old_chain
);
6422 xdb_handle_command (char *args
, int from_tty
)
6425 struct cleanup
*old_chain
;
6428 error_no_arg (_("xdb command"));
6430 /* Break the command line up into args. */
6432 argv
= gdb_buildargv (args
);
6433 old_chain
= make_cleanup_freeargv (argv
);
6434 if (argv
[1] != (char *) NULL
)
6439 bufLen
= strlen (argv
[0]) + 20;
6440 argBuf
= (char *) xmalloc (bufLen
);
6444 enum gdb_signal oursig
;
6446 oursig
= gdb_signal_from_name (argv
[0]);
6447 memset (argBuf
, 0, bufLen
);
6448 if (strcmp (argv
[1], "Q") == 0)
6449 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6452 if (strcmp (argv
[1], "s") == 0)
6454 if (!signal_stop
[oursig
])
6455 sprintf (argBuf
, "%s %s", argv
[0], "stop");
6457 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
6459 else if (strcmp (argv
[1], "i") == 0)
6461 if (!signal_program
[oursig
])
6462 sprintf (argBuf
, "%s %s", argv
[0], "pass");
6464 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
6466 else if (strcmp (argv
[1], "r") == 0)
6468 if (!signal_print
[oursig
])
6469 sprintf (argBuf
, "%s %s", argv
[0], "print");
6471 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6477 handle_command (argBuf
, from_tty
);
6479 printf_filtered (_("Invalid signal handling flag.\n"));
6484 do_cleanups (old_chain
);
6488 gdb_signal_from_command (int num
)
6490 if (num
>= 1 && num
<= 15)
6491 return (enum gdb_signal
) num
;
6492 error (_("Only signals 1-15 are valid as numeric signals.\n\
6493 Use \"info signals\" for a list of symbolic signals."));
6496 /* Print current contents of the tables set by the handle command.
6497 It is possible we should just be printing signals actually used
6498 by the current target (but for things to work right when switching
6499 targets, all signals should be in the signal tables). */
6502 signals_info (char *signum_exp
, int from_tty
)
6504 enum gdb_signal oursig
;
6506 sig_print_header ();
6510 /* First see if this is a symbol name. */
6511 oursig
= gdb_signal_from_name (signum_exp
);
6512 if (oursig
== GDB_SIGNAL_UNKNOWN
)
6514 /* No, try numeric. */
6516 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
6518 sig_print_info (oursig
);
6522 printf_filtered ("\n");
6523 /* These ugly casts brought to you by the native VAX compiler. */
6524 for (oursig
= GDB_SIGNAL_FIRST
;
6525 (int) oursig
< (int) GDB_SIGNAL_LAST
;
6526 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
6530 if (oursig
!= GDB_SIGNAL_UNKNOWN
6531 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
6532 sig_print_info (oursig
);
6535 printf_filtered (_("\nUse the \"handle\" command "
6536 "to change these tables.\n"));
6539 /* Check if it makes sense to read $_siginfo from the current thread
6540 at this point. If not, throw an error. */
6543 validate_siginfo_access (void)
6545 /* No current inferior, no siginfo. */
6546 if (ptid_equal (inferior_ptid
, null_ptid
))
6547 error (_("No thread selected."));
6549 /* Don't try to read from a dead thread. */
6550 if (is_exited (inferior_ptid
))
6551 error (_("The current thread has terminated"));
6553 /* ... or from a spinning thread. */
6554 if (is_running (inferior_ptid
))
6555 error (_("Selected thread is running."));
6558 /* The $_siginfo convenience variable is a bit special. We don't know
6559 for sure the type of the value until we actually have a chance to
6560 fetch the data. The type can change depending on gdbarch, so it is
6561 also dependent on which thread you have selected.
6563 1. making $_siginfo be an internalvar that creates a new value on
6566 2. making the value of $_siginfo be an lval_computed value. */
6568 /* This function implements the lval_computed support for reading a
6572 siginfo_value_read (struct value
*v
)
6574 LONGEST transferred
;
6576 validate_siginfo_access ();
6579 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
6581 value_contents_all_raw (v
),
6583 TYPE_LENGTH (value_type (v
)));
6585 if (transferred
!= TYPE_LENGTH (value_type (v
)))
6586 error (_("Unable to read siginfo"));
6589 /* This function implements the lval_computed support for writing a
6593 siginfo_value_write (struct value
*v
, struct value
*fromval
)
6595 LONGEST transferred
;
6597 validate_siginfo_access ();
6599 transferred
= target_write (¤t_target
,
6600 TARGET_OBJECT_SIGNAL_INFO
,
6602 value_contents_all_raw (fromval
),
6604 TYPE_LENGTH (value_type (fromval
)));
6606 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
6607 error (_("Unable to write siginfo"));
6610 static const struct lval_funcs siginfo_value_funcs
=
6616 /* Return a new value with the correct type for the siginfo object of
6617 the current thread using architecture GDBARCH. Return a void value
6618 if there's no object available. */
6620 static struct value
*
6621 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
6624 if (target_has_stack
6625 && !ptid_equal (inferior_ptid
, null_ptid
)
6626 && gdbarch_get_siginfo_type_p (gdbarch
))
6628 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6630 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
6633 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
6637 /* infcall_suspend_state contains state about the program itself like its
6638 registers and any signal it received when it last stopped.
6639 This state must be restored regardless of how the inferior function call
6640 ends (either successfully, or after it hits a breakpoint or signal)
6641 if the program is to properly continue where it left off. */
6643 struct infcall_suspend_state
6645 struct thread_suspend_state thread_suspend
;
6646 #if 0 /* Currently unused and empty structures are not valid C. */
6647 struct inferior_suspend_state inferior_suspend
;
6652 struct regcache
*registers
;
6654 /* Format of SIGINFO_DATA or NULL if it is not present. */
6655 struct gdbarch
*siginfo_gdbarch
;
6657 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
6658 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
6659 content would be invalid. */
6660 gdb_byte
*siginfo_data
;
6663 struct infcall_suspend_state
*
6664 save_infcall_suspend_state (void)
6666 struct infcall_suspend_state
*inf_state
;
6667 struct thread_info
*tp
= inferior_thread ();
6668 struct inferior
*inf
= current_inferior ();
6669 struct regcache
*regcache
= get_current_regcache ();
6670 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6671 gdb_byte
*siginfo_data
= NULL
;
6673 if (gdbarch_get_siginfo_type_p (gdbarch
))
6675 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6676 size_t len
= TYPE_LENGTH (type
);
6677 struct cleanup
*back_to
;
6679 siginfo_data
= xmalloc (len
);
6680 back_to
= make_cleanup (xfree
, siginfo_data
);
6682 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6683 siginfo_data
, 0, len
) == len
)
6684 discard_cleanups (back_to
);
6687 /* Errors ignored. */
6688 do_cleanups (back_to
);
6689 siginfo_data
= NULL
;
6693 inf_state
= XZALLOC (struct infcall_suspend_state
);
6697 inf_state
->siginfo_gdbarch
= gdbarch
;
6698 inf_state
->siginfo_data
= siginfo_data
;
6701 inf_state
->thread_suspend
= tp
->suspend
;
6702 #if 0 /* Currently unused and empty structures are not valid C. */
6703 inf_state
->inferior_suspend
= inf
->suspend
;
6706 /* run_inferior_call will not use the signal due to its `proceed' call with
6707 GDB_SIGNAL_0 anyway. */
6708 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6710 inf_state
->stop_pc
= stop_pc
;
6712 inf_state
->registers
= regcache_dup (regcache
);
6717 /* Restore inferior session state to INF_STATE. */
6720 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6722 struct thread_info
*tp
= inferior_thread ();
6723 struct inferior
*inf
= current_inferior ();
6724 struct regcache
*regcache
= get_current_regcache ();
6725 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6727 tp
->suspend
= inf_state
->thread_suspend
;
6728 #if 0 /* Currently unused and empty structures are not valid C. */
6729 inf
->suspend
= inf_state
->inferior_suspend
;
6732 stop_pc
= inf_state
->stop_pc
;
6734 if (inf_state
->siginfo_gdbarch
== gdbarch
)
6736 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6737 size_t len
= TYPE_LENGTH (type
);
6739 /* Errors ignored. */
6740 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6741 inf_state
->siginfo_data
, 0, len
);
6744 /* The inferior can be gone if the user types "print exit(0)"
6745 (and perhaps other times). */
6746 if (target_has_execution
)
6747 /* NB: The register write goes through to the target. */
6748 regcache_cpy (regcache
, inf_state
->registers
);
6750 discard_infcall_suspend_state (inf_state
);
6754 do_restore_infcall_suspend_state_cleanup (void *state
)
6756 restore_infcall_suspend_state (state
);
6760 make_cleanup_restore_infcall_suspend_state
6761 (struct infcall_suspend_state
*inf_state
)
6763 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
6767 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6769 regcache_xfree (inf_state
->registers
);
6770 xfree (inf_state
->siginfo_data
);
6775 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
6777 return inf_state
->registers
;
6780 /* infcall_control_state contains state regarding gdb's control of the
6781 inferior itself like stepping control. It also contains session state like
6782 the user's currently selected frame. */
6784 struct infcall_control_state
6786 struct thread_control_state thread_control
;
6787 struct inferior_control_state inferior_control
;
6790 enum stop_stack_kind stop_stack_dummy
;
6791 int stopped_by_random_signal
;
6792 int stop_after_trap
;
6794 /* ID if the selected frame when the inferior function call was made. */
6795 struct frame_id selected_frame_id
;
6798 /* Save all of the information associated with the inferior<==>gdb
6801 struct infcall_control_state
*
6802 save_infcall_control_state (void)
6804 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
6805 struct thread_info
*tp
= inferior_thread ();
6806 struct inferior
*inf
= current_inferior ();
6808 inf_status
->thread_control
= tp
->control
;
6809 inf_status
->inferior_control
= inf
->control
;
6811 tp
->control
.step_resume_breakpoint
= NULL
;
6812 tp
->control
.exception_resume_breakpoint
= NULL
;
6814 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
6815 chain. If caller's caller is walking the chain, they'll be happier if we
6816 hand them back the original chain when restore_infcall_control_state is
6818 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
6821 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
6822 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
6823 inf_status
->stop_after_trap
= stop_after_trap
;
6825 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
6831 restore_selected_frame (void *args
)
6833 struct frame_id
*fid
= (struct frame_id
*) args
;
6834 struct frame_info
*frame
;
6836 frame
= frame_find_by_id (*fid
);
6838 /* If inf_status->selected_frame_id is NULL, there was no previously
6842 warning (_("Unable to restore previously selected frame."));
6846 select_frame (frame
);
6851 /* Restore inferior session state to INF_STATUS. */
6854 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
6856 struct thread_info
*tp
= inferior_thread ();
6857 struct inferior
*inf
= current_inferior ();
6859 if (tp
->control
.step_resume_breakpoint
)
6860 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
6862 if (tp
->control
.exception_resume_breakpoint
)
6863 tp
->control
.exception_resume_breakpoint
->disposition
6864 = disp_del_at_next_stop
;
6866 /* Handle the bpstat_copy of the chain. */
6867 bpstat_clear (&tp
->control
.stop_bpstat
);
6869 tp
->control
= inf_status
->thread_control
;
6870 inf
->control
= inf_status
->inferior_control
;
6873 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
6874 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
6875 stop_after_trap
= inf_status
->stop_after_trap
;
6877 if (target_has_stack
)
6879 /* The point of catch_errors is that if the stack is clobbered,
6880 walking the stack might encounter a garbage pointer and
6881 error() trying to dereference it. */
6883 (restore_selected_frame
, &inf_status
->selected_frame_id
,
6884 "Unable to restore previously selected frame:\n",
6885 RETURN_MASK_ERROR
) == 0)
6886 /* Error in restoring the selected frame. Select the innermost
6888 select_frame (get_current_frame ());
6895 do_restore_infcall_control_state_cleanup (void *sts
)
6897 restore_infcall_control_state (sts
);
6901 make_cleanup_restore_infcall_control_state
6902 (struct infcall_control_state
*inf_status
)
6904 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
6908 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
6910 if (inf_status
->thread_control
.step_resume_breakpoint
)
6911 inf_status
->thread_control
.step_resume_breakpoint
->disposition
6912 = disp_del_at_next_stop
;
6914 if (inf_status
->thread_control
.exception_resume_breakpoint
)
6915 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
6916 = disp_del_at_next_stop
;
6918 /* See save_infcall_control_state for info on stop_bpstat. */
6919 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
6925 ptid_match (ptid_t ptid
, ptid_t filter
)
6927 if (ptid_equal (filter
, minus_one_ptid
))
6929 if (ptid_is_pid (filter
)
6930 && ptid_get_pid (ptid
) == ptid_get_pid (filter
))
6932 else if (ptid_equal (ptid
, filter
))
6938 /* restore_inferior_ptid() will be used by the cleanup machinery
6939 to restore the inferior_ptid value saved in a call to
6940 save_inferior_ptid(). */
6943 restore_inferior_ptid (void *arg
)
6945 ptid_t
*saved_ptid_ptr
= arg
;
6947 inferior_ptid
= *saved_ptid_ptr
;
6951 /* Save the value of inferior_ptid so that it may be restored by a
6952 later call to do_cleanups(). Returns the struct cleanup pointer
6953 needed for later doing the cleanup. */
6956 save_inferior_ptid (void)
6958 ptid_t
*saved_ptid_ptr
;
6960 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
6961 *saved_ptid_ptr
= inferior_ptid
;
6962 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
6966 /* User interface for reverse debugging:
6967 Set exec-direction / show exec-direction commands
6968 (returns error unless target implements to_set_exec_direction method). */
6970 int execution_direction
= EXEC_FORWARD
;
6971 static const char exec_forward
[] = "forward";
6972 static const char exec_reverse
[] = "reverse";
6973 static const char *exec_direction
= exec_forward
;
6974 static const char *const exec_direction_names
[] = {
6981 set_exec_direction_func (char *args
, int from_tty
,
6982 struct cmd_list_element
*cmd
)
6984 if (target_can_execute_reverse
)
6986 if (!strcmp (exec_direction
, exec_forward
))
6987 execution_direction
= EXEC_FORWARD
;
6988 else if (!strcmp (exec_direction
, exec_reverse
))
6989 execution_direction
= EXEC_REVERSE
;
6993 exec_direction
= exec_forward
;
6994 error (_("Target does not support this operation."));
6999 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7000 struct cmd_list_element
*cmd
, const char *value
)
7002 switch (execution_direction
) {
7004 fprintf_filtered (out
, _("Forward.\n"));
7007 fprintf_filtered (out
, _("Reverse.\n"));
7010 internal_error (__FILE__
, __LINE__
,
7011 _("bogus execution_direction value: %d"),
7012 (int) execution_direction
);
7016 /* User interface for non-stop mode. */
7021 set_non_stop (char *args
, int from_tty
,
7022 struct cmd_list_element
*c
)
7024 if (target_has_execution
)
7026 non_stop_1
= non_stop
;
7027 error (_("Cannot change this setting while the inferior is running."));
7030 non_stop
= non_stop_1
;
7034 show_non_stop (struct ui_file
*file
, int from_tty
,
7035 struct cmd_list_element
*c
, const char *value
)
7037 fprintf_filtered (file
,
7038 _("Controlling the inferior in non-stop mode is %s.\n"),
7043 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7044 struct cmd_list_element
*c
, const char *value
)
7046 fprintf_filtered (file
, _("Resuming the execution of threads "
7047 "of all processes is %s.\n"), value
);
7050 /* Implementation of `siginfo' variable. */
7052 static const struct internalvar_funcs siginfo_funcs
=
7060 _initialize_infrun (void)
7065 add_info ("signals", signals_info
, _("\
7066 What debugger does when program gets various signals.\n\
7067 Specify a signal as argument to print info on that signal only."));
7068 add_info_alias ("handle", "signals", 0);
7070 add_com ("handle", class_run
, handle_command
, _("\
7071 Specify how to handle a signal.\n\
7072 Args are signals and actions to apply to those signals.\n\
7073 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7074 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7075 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7076 The special arg \"all\" is recognized to mean all signals except those\n\
7077 used by the debugger, typically SIGTRAP and SIGINT.\n\
7078 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7079 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7080 Stop means reenter debugger if this signal happens (implies print).\n\
7081 Print means print a message if this signal happens.\n\
7082 Pass means let program see this signal; otherwise program doesn't know.\n\
7083 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7084 Pass and Stop may be combined."));
7087 add_com ("lz", class_info
, signals_info
, _("\
7088 What debugger does when program gets various signals.\n\
7089 Specify a signal as argument to print info on that signal only."));
7090 add_com ("z", class_run
, xdb_handle_command
, _("\
7091 Specify how to handle a signal.\n\
7092 Args are signals and actions to apply to those signals.\n\
7093 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7094 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7095 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7096 The special arg \"all\" is recognized to mean all signals except those\n\
7097 used by the debugger, typically SIGTRAP and SIGINT.\n\
7098 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7099 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7100 nopass), \"Q\" (noprint)\n\
7101 Stop means reenter debugger if this signal happens (implies print).\n\
7102 Print means print a message if this signal happens.\n\
7103 Pass means let program see this signal; otherwise program doesn't know.\n\
7104 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7105 Pass and Stop may be combined."));
7109 stop_command
= add_cmd ("stop", class_obscure
,
7110 not_just_help_class_command
, _("\
7111 There is no `stop' command, but you can set a hook on `stop'.\n\
7112 This allows you to set a list of commands to be run each time execution\n\
7113 of the program stops."), &cmdlist
);
7115 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7116 Set inferior debugging."), _("\
7117 Show inferior debugging."), _("\
7118 When non-zero, inferior specific debugging is enabled."),
7121 &setdebuglist
, &showdebuglist
);
7123 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7124 &debug_displaced
, _("\
7125 Set displaced stepping debugging."), _("\
7126 Show displaced stepping debugging."), _("\
7127 When non-zero, displaced stepping specific debugging is enabled."),
7129 show_debug_displaced
,
7130 &setdebuglist
, &showdebuglist
);
7132 add_setshow_boolean_cmd ("non-stop", no_class
,
7134 Set whether gdb controls the inferior in non-stop mode."), _("\
7135 Show whether gdb controls the inferior in non-stop mode."), _("\
7136 When debugging a multi-threaded program and this setting is\n\
7137 off (the default, also called all-stop mode), when one thread stops\n\
7138 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7139 all other threads in the program while you interact with the thread of\n\
7140 interest. When you continue or step a thread, you can allow the other\n\
7141 threads to run, or have them remain stopped, but while you inspect any\n\
7142 thread's state, all threads stop.\n\
7144 In non-stop mode, when one thread stops, other threads can continue\n\
7145 to run freely. You'll be able to step each thread independently,\n\
7146 leave it stopped or free to run as needed."),
7152 numsigs
= (int) GDB_SIGNAL_LAST
;
7153 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7154 signal_print
= (unsigned char *)
7155 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7156 signal_program
= (unsigned char *)
7157 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7158 signal_pass
= (unsigned char *)
7159 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7160 for (i
= 0; i
< numsigs
; i
++)
7163 signal_print
[i
] = 1;
7164 signal_program
[i
] = 1;
7167 /* Signals caused by debugger's own actions
7168 should not be given to the program afterwards. */
7169 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7170 signal_program
[GDB_SIGNAL_INT
] = 0;
7172 /* Signals that are not errors should not normally enter the debugger. */
7173 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7174 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7175 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7176 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7177 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7178 signal_print
[GDB_SIGNAL_PROF
] = 0;
7179 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7180 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7181 signal_stop
[GDB_SIGNAL_IO
] = 0;
7182 signal_print
[GDB_SIGNAL_IO
] = 0;
7183 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7184 signal_print
[GDB_SIGNAL_POLL
] = 0;
7185 signal_stop
[GDB_SIGNAL_URG
] = 0;
7186 signal_print
[GDB_SIGNAL_URG
] = 0;
7187 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7188 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7189 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7190 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7192 /* These signals are used internally by user-level thread
7193 implementations. (See signal(5) on Solaris.) Like the above
7194 signals, a healthy program receives and handles them as part of
7195 its normal operation. */
7196 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7197 signal_print
[GDB_SIGNAL_LWP
] = 0;
7198 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7199 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7200 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7201 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7203 /* Update cached state. */
7204 signal_cache_update (-1);
7206 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7207 &stop_on_solib_events
, _("\
7208 Set stopping for shared library events."), _("\
7209 Show stopping for shared library events."), _("\
7210 If nonzero, gdb will give control to the user when the dynamic linker\n\
7211 notifies gdb of shared library events. The most common event of interest\n\
7212 to the user would be loading/unloading of a new library."),
7214 show_stop_on_solib_events
,
7215 &setlist
, &showlist
);
7217 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7218 follow_fork_mode_kind_names
,
7219 &follow_fork_mode_string
, _("\
7220 Set debugger response to a program call of fork or vfork."), _("\
7221 Show debugger response to a program call of fork or vfork."), _("\
7222 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7223 parent - the original process is debugged after a fork\n\
7224 child - the new process is debugged after a fork\n\
7225 The unfollowed process will continue to run.\n\
7226 By default, the debugger will follow the parent process."),
7228 show_follow_fork_mode_string
,
7229 &setlist
, &showlist
);
7231 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7232 follow_exec_mode_names
,
7233 &follow_exec_mode_string
, _("\
7234 Set debugger response to a program call of exec."), _("\
7235 Show debugger response to a program call of exec."), _("\
7236 An exec call replaces the program image of a process.\n\
7238 follow-exec-mode can be:\n\
7240 new - the debugger creates a new inferior and rebinds the process\n\
7241 to this new inferior. The program the process was running before\n\
7242 the exec call can be restarted afterwards by restarting the original\n\
7245 same - the debugger keeps the process bound to the same inferior.\n\
7246 The new executable image replaces the previous executable loaded in\n\
7247 the inferior. Restarting the inferior after the exec call restarts\n\
7248 the executable the process was running after the exec call.\n\
7250 By default, the debugger will use the same inferior."),
7252 show_follow_exec_mode_string
,
7253 &setlist
, &showlist
);
7255 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7256 scheduler_enums
, &scheduler_mode
, _("\
7257 Set mode for locking scheduler during execution."), _("\
7258 Show mode for locking scheduler during execution."), _("\
7259 off == no locking (threads may preempt at any time)\n\
7260 on == full locking (no thread except the current thread may run)\n\
7261 step == scheduler locked during every single-step operation.\n\
7262 In this mode, no other thread may run during a step command.\n\
7263 Other threads may run while stepping over a function call ('next')."),
7264 set_schedlock_func
, /* traps on target vector */
7265 show_scheduler_mode
,
7266 &setlist
, &showlist
);
7268 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7269 Set mode for resuming threads of all processes."), _("\
7270 Show mode for resuming threads of all processes."), _("\
7271 When on, execution commands (such as 'continue' or 'next') resume all\n\
7272 threads of all processes. When off (which is the default), execution\n\
7273 commands only resume the threads of the current process. The set of\n\
7274 threads that are resumed is further refined by the scheduler-locking\n\
7275 mode (see help set scheduler-locking)."),
7277 show_schedule_multiple
,
7278 &setlist
, &showlist
);
7280 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7281 Set mode of the step operation."), _("\
7282 Show mode of the step operation."), _("\
7283 When set, doing a step over a function without debug line information\n\
7284 will stop at the first instruction of that function. Otherwise, the\n\
7285 function is skipped and the step command stops at a different source line."),
7287 show_step_stop_if_no_debug
,
7288 &setlist
, &showlist
);
7290 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
7291 &can_use_displaced_stepping
, _("\
7292 Set debugger's willingness to use displaced stepping."), _("\
7293 Show debugger's willingness to use displaced stepping."), _("\
7294 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7295 supported by the target architecture. If off, gdb will not use displaced\n\
7296 stepping to step over breakpoints, even if such is supported by the target\n\
7297 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7298 if the target architecture supports it and non-stop mode is active, but will not\n\
7299 use it in all-stop mode (see help set non-stop)."),
7301 show_can_use_displaced_stepping
,
7302 &setlist
, &showlist
);
7304 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7305 &exec_direction
, _("Set direction of execution.\n\
7306 Options are 'forward' or 'reverse'."),
7307 _("Show direction of execution (forward/reverse)."),
7308 _("Tells gdb whether to execute forward or backward."),
7309 set_exec_direction_func
, show_exec_direction_func
,
7310 &setlist
, &showlist
);
7312 /* Set/show detach-on-fork: user-settable mode. */
7314 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7315 Set whether gdb will detach the child of a fork."), _("\
7316 Show whether gdb will detach the child of a fork."), _("\
7317 Tells gdb whether to detach the child of a fork."),
7318 NULL
, NULL
, &setlist
, &showlist
);
7320 /* Set/show disable address space randomization mode. */
7322 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7323 &disable_randomization
, _("\
7324 Set disabling of debuggee's virtual address space randomization."), _("\
7325 Show disabling of debuggee's virtual address space randomization."), _("\
7326 When this mode is on (which is the default), randomization of the virtual\n\
7327 address space is disabled. Standalone programs run with the randomization\n\
7328 enabled by default on some platforms."),
7329 &set_disable_randomization
,
7330 &show_disable_randomization
,
7331 &setlist
, &showlist
);
7333 /* ptid initializations */
7334 inferior_ptid
= null_ptid
;
7335 target_last_wait_ptid
= minus_one_ptid
;
7337 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7338 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7339 observer_attach_thread_exit (infrun_thread_thread_exit
);
7340 observer_attach_inferior_exit (infrun_inferior_exit
);
7342 /* Explicitly create without lookup, since that tries to create a
7343 value with a void typed value, and when we get here, gdbarch
7344 isn't initialized yet. At this point, we're quite sure there
7345 isn't another convenience variable of the same name. */
7346 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7348 add_setshow_boolean_cmd ("observer", no_class
,
7349 &observer_mode_1
, _("\
7350 Set whether gdb controls the inferior in observer mode."), _("\
7351 Show whether gdb controls the inferior in observer mode."), _("\
7352 In observer mode, GDB can get data from the inferior, but not\n\
7353 affect its execution. Registers and memory may not be changed,\n\
7354 breakpoints may not be set, and the program cannot be interrupted\n\