1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2012 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 #include "gdb_string.h"
27 #include "exceptions.h"
28 #include "breakpoint.h"
32 #include "cli/cli-script.h"
34 #include "gdbthread.h"
46 #include "dictionary.h"
48 #include "gdb_assert.h"
49 #include "mi/mi-common.h"
50 #include "event-top.h"
52 #include "inline-frame.h"
54 #include "tracepoint.h"
55 #include "continuations.h"
61 /* Prototypes for local functions */
63 static void signals_info (char *, int);
65 static void handle_command (char *, int);
67 static void sig_print_info (enum gdb_signal
);
69 static void sig_print_header (void);
71 static void resume_cleanups (void *);
73 static int hook_stop_stub (void *);
75 static int restore_selected_frame (void *);
77 static int follow_fork (void);
79 static void set_schedlock_func (char *args
, int from_tty
,
80 struct cmd_list_element
*c
);
82 static int currently_stepping (struct thread_info
*tp
);
84 static int currently_stepping_or_nexting_callback (struct thread_info
*tp
,
87 static void xdb_handle_command (char *args
, int from_tty
);
89 static int prepare_to_proceed (int);
91 static void print_exited_reason (int exitstatus
);
93 static void print_signal_exited_reason (enum gdb_signal siggnal
);
95 static void print_no_history_reason (void);
97 static void print_signal_received_reason (enum gdb_signal siggnal
);
99 static void print_end_stepping_range_reason (void);
101 void _initialize_infrun (void);
103 void nullify_last_target_wait_ptid (void);
105 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
107 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
109 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
111 /* When set, stop the 'step' command if we enter a function which has
112 no line number information. The normal behavior is that we step
113 over such function. */
114 int step_stop_if_no_debug
= 0;
116 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
117 struct cmd_list_element
*c
, const char *value
)
119 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
122 /* In asynchronous mode, but simulating synchronous execution. */
124 int sync_execution
= 0;
126 /* wait_for_inferior and normal_stop use this to notify the user
127 when the inferior stopped in a different thread than it had been
130 static ptid_t previous_inferior_ptid
;
132 /* Default behavior is to detach newly forked processes (legacy). */
135 int debug_displaced
= 0;
137 show_debug_displaced (struct ui_file
*file
, int from_tty
,
138 struct cmd_list_element
*c
, const char *value
)
140 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
143 int debug_infrun
= 0;
145 show_debug_infrun (struct ui_file
*file
, int from_tty
,
146 struct cmd_list_element
*c
, const char *value
)
148 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
152 /* Support for disabling address space randomization. */
154 int disable_randomization
= 1;
157 show_disable_randomization (struct ui_file
*file
, int from_tty
,
158 struct cmd_list_element
*c
, const char *value
)
160 if (target_supports_disable_randomization ())
161 fprintf_filtered (file
,
162 _("Disabling randomization of debuggee's "
163 "virtual address space is %s.\n"),
166 fputs_filtered (_("Disabling randomization of debuggee's "
167 "virtual address space is unsupported on\n"
168 "this platform.\n"), file
);
172 set_disable_randomization (char *args
, int from_tty
,
173 struct cmd_list_element
*c
)
175 if (!target_supports_disable_randomization ())
176 error (_("Disabling randomization of debuggee's "
177 "virtual address space is unsupported on\n"
182 /* If the program uses ELF-style shared libraries, then calls to
183 functions in shared libraries go through stubs, which live in a
184 table called the PLT (Procedure Linkage Table). The first time the
185 function is called, the stub sends control to the dynamic linker,
186 which looks up the function's real address, patches the stub so
187 that future calls will go directly to the function, and then passes
188 control to the function.
190 If we are stepping at the source level, we don't want to see any of
191 this --- we just want to skip over the stub and the dynamic linker.
192 The simple approach is to single-step until control leaves the
195 However, on some systems (e.g., Red Hat's 5.2 distribution) the
196 dynamic linker calls functions in the shared C library, so you
197 can't tell from the PC alone whether the dynamic linker is still
198 running. In this case, we use a step-resume breakpoint to get us
199 past the dynamic linker, as if we were using "next" to step over a
202 in_solib_dynsym_resolve_code() says whether we're in the dynamic
203 linker code or not. Normally, this means we single-step. However,
204 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
205 address where we can place a step-resume breakpoint to get past the
206 linker's symbol resolution function.
208 in_solib_dynsym_resolve_code() can generally be implemented in a
209 pretty portable way, by comparing the PC against the address ranges
210 of the dynamic linker's sections.
212 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
213 it depends on internal details of the dynamic linker. It's usually
214 not too hard to figure out where to put a breakpoint, but it
215 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
216 sanity checking. If it can't figure things out, returning zero and
217 getting the (possibly confusing) stepping behavior is better than
218 signalling an error, which will obscure the change in the
221 /* This function returns TRUE if pc is the address of an instruction
222 that lies within the dynamic linker (such as the event hook, or the
225 This function must be used only when a dynamic linker event has
226 been caught, and the inferior is being stepped out of the hook, or
227 undefined results are guaranteed. */
229 #ifndef SOLIB_IN_DYNAMIC_LINKER
230 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
233 /* "Observer mode" is somewhat like a more extreme version of
234 non-stop, in which all GDB operations that might affect the
235 target's execution have been disabled. */
237 static int non_stop_1
= 0;
239 int observer_mode
= 0;
240 static int observer_mode_1
= 0;
243 set_observer_mode (char *args
, int from_tty
,
244 struct cmd_list_element
*c
)
246 extern int pagination_enabled
;
248 if (target_has_execution
)
250 observer_mode_1
= observer_mode
;
251 error (_("Cannot change this setting while the inferior is running."));
254 observer_mode
= observer_mode_1
;
256 may_write_registers
= !observer_mode
;
257 may_write_memory
= !observer_mode
;
258 may_insert_breakpoints
= !observer_mode
;
259 may_insert_tracepoints
= !observer_mode
;
260 /* We can insert fast tracepoints in or out of observer mode,
261 but enable them if we're going into this mode. */
263 may_insert_fast_tracepoints
= 1;
264 may_stop
= !observer_mode
;
265 update_target_permissions ();
267 /* Going *into* observer mode we must force non-stop, then
268 going out we leave it that way. */
271 target_async_permitted
= 1;
272 pagination_enabled
= 0;
273 non_stop
= non_stop_1
= 1;
277 printf_filtered (_("Observer mode is now %s.\n"),
278 (observer_mode
? "on" : "off"));
282 show_observer_mode (struct ui_file
*file
, int from_tty
,
283 struct cmd_list_element
*c
, const char *value
)
285 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
288 /* This updates the value of observer mode based on changes in
289 permissions. Note that we are deliberately ignoring the values of
290 may-write-registers and may-write-memory, since the user may have
291 reason to enable these during a session, for instance to turn on a
292 debugging-related global. */
295 update_observer_mode (void)
299 newval
= (!may_insert_breakpoints
300 && !may_insert_tracepoints
301 && may_insert_fast_tracepoints
305 /* Let the user know if things change. */
306 if (newval
!= observer_mode
)
307 printf_filtered (_("Observer mode is now %s.\n"),
308 (newval
? "on" : "off"));
310 observer_mode
= observer_mode_1
= newval
;
313 /* Tables of how to react to signals; the user sets them. */
315 static unsigned char *signal_stop
;
316 static unsigned char *signal_print
;
317 static unsigned char *signal_program
;
319 /* Table of signals that the target may silently handle.
320 This is automatically determined from the flags above,
321 and simply cached here. */
322 static unsigned char *signal_pass
;
324 #define SET_SIGS(nsigs,sigs,flags) \
326 int signum = (nsigs); \
327 while (signum-- > 0) \
328 if ((sigs)[signum]) \
329 (flags)[signum] = 1; \
332 #define UNSET_SIGS(nsigs,sigs,flags) \
334 int signum = (nsigs); \
335 while (signum-- > 0) \
336 if ((sigs)[signum]) \
337 (flags)[signum] = 0; \
340 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
341 this function is to avoid exporting `signal_program'. */
344 update_signals_program_target (void)
346 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
349 /* Value to pass to target_resume() to cause all threads to resume. */
351 #define RESUME_ALL minus_one_ptid
353 /* Command list pointer for the "stop" placeholder. */
355 static struct cmd_list_element
*stop_command
;
357 /* Function inferior was in as of last step command. */
359 static struct symbol
*step_start_function
;
361 /* Nonzero if we want to give control to the user when we're notified
362 of shared library events by the dynamic linker. */
363 int stop_on_solib_events
;
365 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
366 struct cmd_list_element
*c
, const char *value
)
368 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
372 /* Nonzero means expecting a trace trap
373 and should stop the inferior and return silently when it happens. */
377 /* Save register contents here when executing a "finish" command or are
378 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
379 Thus this contains the return value from the called function (assuming
380 values are returned in a register). */
382 struct regcache
*stop_registers
;
384 /* Nonzero after stop if current stack frame should be printed. */
386 static int stop_print_frame
;
388 /* This is a cached copy of the pid/waitstatus of the last event
389 returned by target_wait()/deprecated_target_wait_hook(). This
390 information is returned by get_last_target_status(). */
391 static ptid_t target_last_wait_ptid
;
392 static struct target_waitstatus target_last_waitstatus
;
394 static void context_switch (ptid_t ptid
);
396 void init_thread_stepping_state (struct thread_info
*tss
);
398 void init_infwait_state (void);
400 static const char follow_fork_mode_child
[] = "child";
401 static const char follow_fork_mode_parent
[] = "parent";
403 static const char *const follow_fork_mode_kind_names
[] = {
404 follow_fork_mode_child
,
405 follow_fork_mode_parent
,
409 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
411 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
412 struct cmd_list_element
*c
, const char *value
)
414 fprintf_filtered (file
,
415 _("Debugger response to a program "
416 "call of fork or vfork is \"%s\".\n"),
421 /* Tell the target to follow the fork we're stopped at. Returns true
422 if the inferior should be resumed; false, if the target for some
423 reason decided it's best not to resume. */
428 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
429 int should_resume
= 1;
430 struct thread_info
*tp
;
432 /* Copy user stepping state to the new inferior thread. FIXME: the
433 followed fork child thread should have a copy of most of the
434 parent thread structure's run control related fields, not just these.
435 Initialized to avoid "may be used uninitialized" warnings from gcc. */
436 struct breakpoint
*step_resume_breakpoint
= NULL
;
437 struct breakpoint
*exception_resume_breakpoint
= NULL
;
438 CORE_ADDR step_range_start
= 0;
439 CORE_ADDR step_range_end
= 0;
440 struct frame_id step_frame_id
= { 0 };
445 struct target_waitstatus wait_status
;
447 /* Get the last target status returned by target_wait(). */
448 get_last_target_status (&wait_ptid
, &wait_status
);
450 /* If not stopped at a fork event, then there's nothing else to
452 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
453 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
456 /* Check if we switched over from WAIT_PTID, since the event was
458 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
459 && !ptid_equal (inferior_ptid
, wait_ptid
))
461 /* We did. Switch back to WAIT_PTID thread, to tell the
462 target to follow it (in either direction). We'll
463 afterwards refuse to resume, and inform the user what
465 switch_to_thread (wait_ptid
);
470 tp
= inferior_thread ();
472 /* If there were any forks/vforks that were caught and are now to be
473 followed, then do so now. */
474 switch (tp
->pending_follow
.kind
)
476 case TARGET_WAITKIND_FORKED
:
477 case TARGET_WAITKIND_VFORKED
:
479 ptid_t parent
, child
;
481 /* If the user did a next/step, etc, over a fork call,
482 preserve the stepping state in the fork child. */
483 if (follow_child
&& should_resume
)
485 step_resume_breakpoint
= clone_momentary_breakpoint
486 (tp
->control
.step_resume_breakpoint
);
487 step_range_start
= tp
->control
.step_range_start
;
488 step_range_end
= tp
->control
.step_range_end
;
489 step_frame_id
= tp
->control
.step_frame_id
;
490 exception_resume_breakpoint
491 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
493 /* For now, delete the parent's sr breakpoint, otherwise,
494 parent/child sr breakpoints are considered duplicates,
495 and the child version will not be installed. Remove
496 this when the breakpoints module becomes aware of
497 inferiors and address spaces. */
498 delete_step_resume_breakpoint (tp
);
499 tp
->control
.step_range_start
= 0;
500 tp
->control
.step_range_end
= 0;
501 tp
->control
.step_frame_id
= null_frame_id
;
502 delete_exception_resume_breakpoint (tp
);
505 parent
= inferior_ptid
;
506 child
= tp
->pending_follow
.value
.related_pid
;
508 /* Tell the target to do whatever is necessary to follow
509 either parent or child. */
510 if (target_follow_fork (follow_child
))
512 /* Target refused to follow, or there's some other reason
513 we shouldn't resume. */
518 /* This pending follow fork event is now handled, one way
519 or another. The previous selected thread may be gone
520 from the lists by now, but if it is still around, need
521 to clear the pending follow request. */
522 tp
= find_thread_ptid (parent
);
524 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
526 /* This makes sure we don't try to apply the "Switched
527 over from WAIT_PID" logic above. */
528 nullify_last_target_wait_ptid ();
530 /* If we followed the child, switch to it... */
533 switch_to_thread (child
);
535 /* ... and preserve the stepping state, in case the
536 user was stepping over the fork call. */
539 tp
= inferior_thread ();
540 tp
->control
.step_resume_breakpoint
541 = step_resume_breakpoint
;
542 tp
->control
.step_range_start
= step_range_start
;
543 tp
->control
.step_range_end
= step_range_end
;
544 tp
->control
.step_frame_id
= step_frame_id
;
545 tp
->control
.exception_resume_breakpoint
546 = exception_resume_breakpoint
;
550 /* If we get here, it was because we're trying to
551 resume from a fork catchpoint, but, the user
552 has switched threads away from the thread that
553 forked. In that case, the resume command
554 issued is most likely not applicable to the
555 child, so just warn, and refuse to resume. */
556 warning (_("Not resuming: switched threads "
557 "before following fork child.\n"));
560 /* Reset breakpoints in the child as appropriate. */
561 follow_inferior_reset_breakpoints ();
564 switch_to_thread (parent
);
568 case TARGET_WAITKIND_SPURIOUS
:
569 /* Nothing to follow. */
572 internal_error (__FILE__
, __LINE__
,
573 "Unexpected pending_follow.kind %d\n",
574 tp
->pending_follow
.kind
);
578 return should_resume
;
582 follow_inferior_reset_breakpoints (void)
584 struct thread_info
*tp
= inferior_thread ();
586 /* Was there a step_resume breakpoint? (There was if the user
587 did a "next" at the fork() call.) If so, explicitly reset its
590 step_resumes are a form of bp that are made to be per-thread.
591 Since we created the step_resume bp when the parent process
592 was being debugged, and now are switching to the child process,
593 from the breakpoint package's viewpoint, that's a switch of
594 "threads". We must update the bp's notion of which thread
595 it is for, or it'll be ignored when it triggers. */
597 if (tp
->control
.step_resume_breakpoint
)
598 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
600 if (tp
->control
.exception_resume_breakpoint
)
601 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
603 /* Reinsert all breakpoints in the child. The user may have set
604 breakpoints after catching the fork, in which case those
605 were never set in the child, but only in the parent. This makes
606 sure the inserted breakpoints match the breakpoint list. */
608 breakpoint_re_set ();
609 insert_breakpoints ();
612 /* The child has exited or execed: resume threads of the parent the
613 user wanted to be executing. */
616 proceed_after_vfork_done (struct thread_info
*thread
,
619 int pid
= * (int *) arg
;
621 if (ptid_get_pid (thread
->ptid
) == pid
622 && is_running (thread
->ptid
)
623 && !is_executing (thread
->ptid
)
624 && !thread
->stop_requested
625 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
628 fprintf_unfiltered (gdb_stdlog
,
629 "infrun: resuming vfork parent thread %s\n",
630 target_pid_to_str (thread
->ptid
));
632 switch_to_thread (thread
->ptid
);
633 clear_proceed_status ();
634 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
, 0);
640 /* Called whenever we notice an exec or exit event, to handle
641 detaching or resuming a vfork parent. */
644 handle_vfork_child_exec_or_exit (int exec
)
646 struct inferior
*inf
= current_inferior ();
648 if (inf
->vfork_parent
)
650 int resume_parent
= -1;
652 /* This exec or exit marks the end of the shared memory region
653 between the parent and the child. If the user wanted to
654 detach from the parent, now is the time. */
656 if (inf
->vfork_parent
->pending_detach
)
658 struct thread_info
*tp
;
659 struct cleanup
*old_chain
;
660 struct program_space
*pspace
;
661 struct address_space
*aspace
;
663 /* follow-fork child, detach-on-fork on. */
665 old_chain
= make_cleanup_restore_current_thread ();
667 /* We're letting loose of the parent. */
668 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
669 switch_to_thread (tp
->ptid
);
671 /* We're about to detach from the parent, which implicitly
672 removes breakpoints from its address space. There's a
673 catch here: we want to reuse the spaces for the child,
674 but, parent/child are still sharing the pspace at this
675 point, although the exec in reality makes the kernel give
676 the child a fresh set of new pages. The problem here is
677 that the breakpoints module being unaware of this, would
678 likely chose the child process to write to the parent
679 address space. Swapping the child temporarily away from
680 the spaces has the desired effect. Yes, this is "sort
683 pspace
= inf
->pspace
;
684 aspace
= inf
->aspace
;
688 if (debug_infrun
|| info_verbose
)
690 target_terminal_ours ();
693 fprintf_filtered (gdb_stdlog
,
694 "Detaching vfork parent process "
695 "%d after child exec.\n",
696 inf
->vfork_parent
->pid
);
698 fprintf_filtered (gdb_stdlog
,
699 "Detaching vfork parent process "
700 "%d after child exit.\n",
701 inf
->vfork_parent
->pid
);
704 target_detach (NULL
, 0);
707 inf
->pspace
= pspace
;
708 inf
->aspace
= aspace
;
710 do_cleanups (old_chain
);
714 /* We're staying attached to the parent, so, really give the
715 child a new address space. */
716 inf
->pspace
= add_program_space (maybe_new_address_space ());
717 inf
->aspace
= inf
->pspace
->aspace
;
719 set_current_program_space (inf
->pspace
);
721 resume_parent
= inf
->vfork_parent
->pid
;
723 /* Break the bonds. */
724 inf
->vfork_parent
->vfork_child
= NULL
;
728 struct cleanup
*old_chain
;
729 struct program_space
*pspace
;
731 /* If this is a vfork child exiting, then the pspace and
732 aspaces were shared with the parent. Since we're
733 reporting the process exit, we'll be mourning all that is
734 found in the address space, and switching to null_ptid,
735 preparing to start a new inferior. But, since we don't
736 want to clobber the parent's address/program spaces, we
737 go ahead and create a new one for this exiting
740 /* Switch to null_ptid, so that clone_program_space doesn't want
741 to read the selected frame of a dead process. */
742 old_chain
= save_inferior_ptid ();
743 inferior_ptid
= null_ptid
;
745 /* This inferior is dead, so avoid giving the breakpoints
746 module the option to write through to it (cloning a
747 program space resets breakpoints). */
750 pspace
= add_program_space (maybe_new_address_space ());
751 set_current_program_space (pspace
);
753 inf
->symfile_flags
= SYMFILE_NO_READ
;
754 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
755 inf
->pspace
= pspace
;
756 inf
->aspace
= pspace
->aspace
;
758 /* Put back inferior_ptid. We'll continue mourning this
760 do_cleanups (old_chain
);
762 resume_parent
= inf
->vfork_parent
->pid
;
763 /* Break the bonds. */
764 inf
->vfork_parent
->vfork_child
= NULL
;
767 inf
->vfork_parent
= NULL
;
769 gdb_assert (current_program_space
== inf
->pspace
);
771 if (non_stop
&& resume_parent
!= -1)
773 /* If the user wanted the parent to be running, let it go
775 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
778 fprintf_unfiltered (gdb_stdlog
,
779 "infrun: resuming vfork parent process %d\n",
782 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
784 do_cleanups (old_chain
);
789 /* Enum strings for "set|show displaced-stepping". */
791 static const char follow_exec_mode_new
[] = "new";
792 static const char follow_exec_mode_same
[] = "same";
793 static const char *const follow_exec_mode_names
[] =
795 follow_exec_mode_new
,
796 follow_exec_mode_same
,
800 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
802 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
803 struct cmd_list_element
*c
, const char *value
)
805 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
808 /* EXECD_PATHNAME is assumed to be non-NULL. */
811 follow_exec (ptid_t pid
, char *execd_pathname
)
813 struct thread_info
*th
= inferior_thread ();
814 struct inferior
*inf
= current_inferior ();
816 /* This is an exec event that we actually wish to pay attention to.
817 Refresh our symbol table to the newly exec'd program, remove any
820 If there are breakpoints, they aren't really inserted now,
821 since the exec() transformed our inferior into a fresh set
824 We want to preserve symbolic breakpoints on the list, since
825 we have hopes that they can be reset after the new a.out's
826 symbol table is read.
828 However, any "raw" breakpoints must be removed from the list
829 (e.g., the solib bp's), since their address is probably invalid
832 And, we DON'T want to call delete_breakpoints() here, since
833 that may write the bp's "shadow contents" (the instruction
834 value that was overwritten witha TRAP instruction). Since
835 we now have a new a.out, those shadow contents aren't valid. */
837 mark_breakpoints_out ();
839 update_breakpoints_after_exec ();
841 /* If there was one, it's gone now. We cannot truly step-to-next
842 statement through an exec(). */
843 th
->control
.step_resume_breakpoint
= NULL
;
844 th
->control
.exception_resume_breakpoint
= NULL
;
845 th
->control
.step_range_start
= 0;
846 th
->control
.step_range_end
= 0;
848 /* The target reports the exec event to the main thread, even if
849 some other thread does the exec, and even if the main thread was
850 already stopped --- if debugging in non-stop mode, it's possible
851 the user had the main thread held stopped in the previous image
852 --- release it now. This is the same behavior as step-over-exec
853 with scheduler-locking on in all-stop mode. */
854 th
->stop_requested
= 0;
856 /* What is this a.out's name? */
857 printf_unfiltered (_("%s is executing new program: %s\n"),
858 target_pid_to_str (inferior_ptid
),
861 /* We've followed the inferior through an exec. Therefore, the
862 inferior has essentially been killed & reborn. */
864 gdb_flush (gdb_stdout
);
866 breakpoint_init_inferior (inf_execd
);
868 if (gdb_sysroot
&& *gdb_sysroot
)
870 char *name
= alloca (strlen (gdb_sysroot
)
871 + strlen (execd_pathname
)
874 strcpy (name
, gdb_sysroot
);
875 strcat (name
, execd_pathname
);
876 execd_pathname
= name
;
879 /* Reset the shared library package. This ensures that we get a
880 shlib event when the child reaches "_start", at which point the
881 dld will have had a chance to initialize the child. */
882 /* Also, loading a symbol file below may trigger symbol lookups, and
883 we don't want those to be satisfied by the libraries of the
884 previous incarnation of this process. */
885 no_shared_libraries (NULL
, 0);
887 if (follow_exec_mode_string
== follow_exec_mode_new
)
889 struct program_space
*pspace
;
891 /* The user wants to keep the old inferior and program spaces
892 around. Create a new fresh one, and switch to it. */
894 inf
= add_inferior (current_inferior ()->pid
);
895 pspace
= add_program_space (maybe_new_address_space ());
896 inf
->pspace
= pspace
;
897 inf
->aspace
= pspace
->aspace
;
899 exit_inferior_num_silent (current_inferior ()->num
);
901 set_current_inferior (inf
);
902 set_current_program_space (pspace
);
905 gdb_assert (current_program_space
== inf
->pspace
);
907 /* That a.out is now the one to use. */
908 exec_file_attach (execd_pathname
, 0);
910 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
911 (Position Independent Executable) main symbol file will get applied by
912 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
913 the breakpoints with the zero displacement. */
915 symbol_file_add (execd_pathname
,
917 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
920 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
921 set_initial_language ();
923 #ifdef SOLIB_CREATE_INFERIOR_HOOK
924 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid
));
926 solib_create_inferior_hook (0);
929 jit_inferior_created_hook ();
931 breakpoint_re_set ();
933 /* Reinsert all breakpoints. (Those which were symbolic have
934 been reset to the proper address in the new a.out, thanks
935 to symbol_file_command...). */
936 insert_breakpoints ();
938 /* The next resume of this inferior should bring it to the shlib
939 startup breakpoints. (If the user had also set bp's on
940 "main" from the old (parent) process, then they'll auto-
941 matically get reset there in the new process.). */
944 /* Non-zero if we just simulating a single-step. This is needed
945 because we cannot remove the breakpoints in the inferior process
946 until after the `wait' in `wait_for_inferior'. */
947 static int singlestep_breakpoints_inserted_p
= 0;
949 /* The thread we inserted single-step breakpoints for. */
950 static ptid_t singlestep_ptid
;
952 /* PC when we started this single-step. */
953 static CORE_ADDR singlestep_pc
;
955 /* If another thread hit the singlestep breakpoint, we save the original
956 thread here so that we can resume single-stepping it later. */
957 static ptid_t saved_singlestep_ptid
;
958 static int stepping_past_singlestep_breakpoint
;
960 /* If not equal to null_ptid, this means that after stepping over breakpoint
961 is finished, we need to switch to deferred_step_ptid, and step it.
963 The use case is when one thread has hit a breakpoint, and then the user
964 has switched to another thread and issued 'step'. We need to step over
965 breakpoint in the thread which hit the breakpoint, but then continue
966 stepping the thread user has selected. */
967 static ptid_t deferred_step_ptid
;
969 /* Displaced stepping. */
971 /* In non-stop debugging mode, we must take special care to manage
972 breakpoints properly; in particular, the traditional strategy for
973 stepping a thread past a breakpoint it has hit is unsuitable.
974 'Displaced stepping' is a tactic for stepping one thread past a
975 breakpoint it has hit while ensuring that other threads running
976 concurrently will hit the breakpoint as they should.
978 The traditional way to step a thread T off a breakpoint in a
979 multi-threaded program in all-stop mode is as follows:
981 a0) Initially, all threads are stopped, and breakpoints are not
983 a1) We single-step T, leaving breakpoints uninserted.
984 a2) We insert breakpoints, and resume all threads.
986 In non-stop debugging, however, this strategy is unsuitable: we
987 don't want to have to stop all threads in the system in order to
988 continue or step T past a breakpoint. Instead, we use displaced
991 n0) Initially, T is stopped, other threads are running, and
992 breakpoints are inserted.
993 n1) We copy the instruction "under" the breakpoint to a separate
994 location, outside the main code stream, making any adjustments
995 to the instruction, register, and memory state as directed by
997 n2) We single-step T over the instruction at its new location.
998 n3) We adjust the resulting register and memory state as directed
999 by T's architecture. This includes resetting T's PC to point
1000 back into the main instruction stream.
1003 This approach depends on the following gdbarch methods:
1005 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1006 indicate where to copy the instruction, and how much space must
1007 be reserved there. We use these in step n1.
1009 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1010 address, and makes any necessary adjustments to the instruction,
1011 register contents, and memory. We use this in step n1.
1013 - gdbarch_displaced_step_fixup adjusts registers and memory after
1014 we have successfuly single-stepped the instruction, to yield the
1015 same effect the instruction would have had if we had executed it
1016 at its original address. We use this in step n3.
1018 - gdbarch_displaced_step_free_closure provides cleanup.
1020 The gdbarch_displaced_step_copy_insn and
1021 gdbarch_displaced_step_fixup functions must be written so that
1022 copying an instruction with gdbarch_displaced_step_copy_insn,
1023 single-stepping across the copied instruction, and then applying
1024 gdbarch_displaced_insn_fixup should have the same effects on the
1025 thread's memory and registers as stepping the instruction in place
1026 would have. Exactly which responsibilities fall to the copy and
1027 which fall to the fixup is up to the author of those functions.
1029 See the comments in gdbarch.sh for details.
1031 Note that displaced stepping and software single-step cannot
1032 currently be used in combination, although with some care I think
1033 they could be made to. Software single-step works by placing
1034 breakpoints on all possible subsequent instructions; if the
1035 displaced instruction is a PC-relative jump, those breakpoints
1036 could fall in very strange places --- on pages that aren't
1037 executable, or at addresses that are not proper instruction
1038 boundaries. (We do generally let other threads run while we wait
1039 to hit the software single-step breakpoint, and they might
1040 encounter such a corrupted instruction.) One way to work around
1041 this would be to have gdbarch_displaced_step_copy_insn fully
1042 simulate the effect of PC-relative instructions (and return NULL)
1043 on architectures that use software single-stepping.
1045 In non-stop mode, we can have independent and simultaneous step
1046 requests, so more than one thread may need to simultaneously step
1047 over a breakpoint. The current implementation assumes there is
1048 only one scratch space per process. In this case, we have to
1049 serialize access to the scratch space. If thread A wants to step
1050 over a breakpoint, but we are currently waiting for some other
1051 thread to complete a displaced step, we leave thread A stopped and
1052 place it in the displaced_step_request_queue. Whenever a displaced
1053 step finishes, we pick the next thread in the queue and start a new
1054 displaced step operation on it. See displaced_step_prepare and
1055 displaced_step_fixup for details. */
1057 struct displaced_step_request
1060 struct displaced_step_request
*next
;
1063 /* Per-inferior displaced stepping state. */
1064 struct displaced_step_inferior_state
1066 /* Pointer to next in linked list. */
1067 struct displaced_step_inferior_state
*next
;
1069 /* The process this displaced step state refers to. */
1072 /* A queue of pending displaced stepping requests. One entry per
1073 thread that needs to do a displaced step. */
1074 struct displaced_step_request
*step_request_queue
;
1076 /* If this is not null_ptid, this is the thread carrying out a
1077 displaced single-step in process PID. This thread's state will
1078 require fixing up once it has completed its step. */
1081 /* The architecture the thread had when we stepped it. */
1082 struct gdbarch
*step_gdbarch
;
1084 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1085 for post-step cleanup. */
1086 struct displaced_step_closure
*step_closure
;
1088 /* The address of the original instruction, and the copy we
1090 CORE_ADDR step_original
, step_copy
;
1092 /* Saved contents of copy area. */
1093 gdb_byte
*step_saved_copy
;
1096 /* The list of states of processes involved in displaced stepping
1098 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1100 /* Get the displaced stepping state of process PID. */
1102 static struct displaced_step_inferior_state
*
1103 get_displaced_stepping_state (int pid
)
1105 struct displaced_step_inferior_state
*state
;
1107 for (state
= displaced_step_inferior_states
;
1109 state
= state
->next
)
1110 if (state
->pid
== pid
)
1116 /* Add a new displaced stepping state for process PID to the displaced
1117 stepping state list, or return a pointer to an already existing
1118 entry, if it already exists. Never returns NULL. */
1120 static struct displaced_step_inferior_state
*
1121 add_displaced_stepping_state (int pid
)
1123 struct displaced_step_inferior_state
*state
;
1125 for (state
= displaced_step_inferior_states
;
1127 state
= state
->next
)
1128 if (state
->pid
== pid
)
1131 state
= xcalloc (1, sizeof (*state
));
1133 state
->next
= displaced_step_inferior_states
;
1134 displaced_step_inferior_states
= state
;
1139 /* If inferior is in displaced stepping, and ADDR equals to starting address
1140 of copy area, return corresponding displaced_step_closure. Otherwise,
1143 struct displaced_step_closure
*
1144 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1146 struct displaced_step_inferior_state
*displaced
1147 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1149 /* If checking the mode of displaced instruction in copy area. */
1150 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1151 && (displaced
->step_copy
== addr
))
1152 return displaced
->step_closure
;
1157 /* Remove the displaced stepping state of process PID. */
1160 remove_displaced_stepping_state (int pid
)
1162 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1164 gdb_assert (pid
!= 0);
1166 it
= displaced_step_inferior_states
;
1167 prev_next_p
= &displaced_step_inferior_states
;
1172 *prev_next_p
= it
->next
;
1177 prev_next_p
= &it
->next
;
1183 infrun_inferior_exit (struct inferior
*inf
)
1185 remove_displaced_stepping_state (inf
->pid
);
1188 /* Enum strings for "set|show displaced-stepping". */
1190 static const char can_use_displaced_stepping_auto
[] = "auto";
1191 static const char can_use_displaced_stepping_on
[] = "on";
1192 static const char can_use_displaced_stepping_off
[] = "off";
1193 static const char *const can_use_displaced_stepping_enum
[] =
1195 can_use_displaced_stepping_auto
,
1196 can_use_displaced_stepping_on
,
1197 can_use_displaced_stepping_off
,
1201 /* If ON, and the architecture supports it, GDB will use displaced
1202 stepping to step over breakpoints. If OFF, or if the architecture
1203 doesn't support it, GDB will instead use the traditional
1204 hold-and-step approach. If AUTO (which is the default), GDB will
1205 decide which technique to use to step over breakpoints depending on
1206 which of all-stop or non-stop mode is active --- displaced stepping
1207 in non-stop mode; hold-and-step in all-stop mode. */
1209 static const char *can_use_displaced_stepping
=
1210 can_use_displaced_stepping_auto
;
1213 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1214 struct cmd_list_element
*c
,
1217 if (can_use_displaced_stepping
== can_use_displaced_stepping_auto
)
1218 fprintf_filtered (file
,
1219 _("Debugger's willingness to use displaced stepping "
1220 "to step over breakpoints is %s (currently %s).\n"),
1221 value
, non_stop
? "on" : "off");
1223 fprintf_filtered (file
,
1224 _("Debugger's willingness to use displaced stepping "
1225 "to step over breakpoints is %s.\n"), value
);
1228 /* Return non-zero if displaced stepping can/should be used to step
1229 over breakpoints. */
1232 use_displaced_stepping (struct gdbarch
*gdbarch
)
1234 return (((can_use_displaced_stepping
== can_use_displaced_stepping_auto
1236 || can_use_displaced_stepping
== can_use_displaced_stepping_on
)
1237 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1238 && !RECORD_IS_USED
);
1241 /* Clean out any stray displaced stepping state. */
1243 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1245 /* Indicate that there is no cleanup pending. */
1246 displaced
->step_ptid
= null_ptid
;
1248 if (displaced
->step_closure
)
1250 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1251 displaced
->step_closure
);
1252 displaced
->step_closure
= NULL
;
1257 displaced_step_clear_cleanup (void *arg
)
1259 struct displaced_step_inferior_state
*state
= arg
;
1261 displaced_step_clear (state
);
1264 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1266 displaced_step_dump_bytes (struct ui_file
*file
,
1267 const gdb_byte
*buf
,
1272 for (i
= 0; i
< len
; i
++)
1273 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1274 fputs_unfiltered ("\n", file
);
1277 /* Prepare to single-step, using displaced stepping.
1279 Note that we cannot use displaced stepping when we have a signal to
1280 deliver. If we have a signal to deliver and an instruction to step
1281 over, then after the step, there will be no indication from the
1282 target whether the thread entered a signal handler or ignored the
1283 signal and stepped over the instruction successfully --- both cases
1284 result in a simple SIGTRAP. In the first case we mustn't do a
1285 fixup, and in the second case we must --- but we can't tell which.
1286 Comments in the code for 'random signals' in handle_inferior_event
1287 explain how we handle this case instead.
1289 Returns 1 if preparing was successful -- this thread is going to be
1290 stepped now; or 0 if displaced stepping this thread got queued. */
1292 displaced_step_prepare (ptid_t ptid
)
1294 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1295 struct regcache
*regcache
= get_thread_regcache (ptid
);
1296 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1297 CORE_ADDR original
, copy
;
1299 struct displaced_step_closure
*closure
;
1300 struct displaced_step_inferior_state
*displaced
;
1303 /* We should never reach this function if the architecture does not
1304 support displaced stepping. */
1305 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1307 /* We have to displaced step one thread at a time, as we only have
1308 access to a single scratch space per inferior. */
1310 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1312 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1314 /* Already waiting for a displaced step to finish. Defer this
1315 request and place in queue. */
1316 struct displaced_step_request
*req
, *new_req
;
1318 if (debug_displaced
)
1319 fprintf_unfiltered (gdb_stdlog
,
1320 "displaced: defering step of %s\n",
1321 target_pid_to_str (ptid
));
1323 new_req
= xmalloc (sizeof (*new_req
));
1324 new_req
->ptid
= ptid
;
1325 new_req
->next
= NULL
;
1327 if (displaced
->step_request_queue
)
1329 for (req
= displaced
->step_request_queue
;
1333 req
->next
= new_req
;
1336 displaced
->step_request_queue
= new_req
;
1342 if (debug_displaced
)
1343 fprintf_unfiltered (gdb_stdlog
,
1344 "displaced: stepping %s now\n",
1345 target_pid_to_str (ptid
));
1348 displaced_step_clear (displaced
);
1350 old_cleanups
= save_inferior_ptid ();
1351 inferior_ptid
= ptid
;
1353 original
= regcache_read_pc (regcache
);
1355 copy
= gdbarch_displaced_step_location (gdbarch
);
1356 len
= gdbarch_max_insn_length (gdbarch
);
1358 /* Save the original contents of the copy area. */
1359 displaced
->step_saved_copy
= xmalloc (len
);
1360 ignore_cleanups
= make_cleanup (free_current_contents
,
1361 &displaced
->step_saved_copy
);
1362 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1364 throw_error (MEMORY_ERROR
,
1365 _("Error accessing memory address %s (%s) for "
1366 "displaced-stepping scratch space."),
1367 paddress (gdbarch
, copy
), safe_strerror (status
));
1368 if (debug_displaced
)
1370 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1371 paddress (gdbarch
, copy
));
1372 displaced_step_dump_bytes (gdb_stdlog
,
1373 displaced
->step_saved_copy
,
1377 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1378 original
, copy
, regcache
);
1380 /* We don't support the fully-simulated case at present. */
1381 gdb_assert (closure
);
1383 /* Save the information we need to fix things up if the step
1385 displaced
->step_ptid
= ptid
;
1386 displaced
->step_gdbarch
= gdbarch
;
1387 displaced
->step_closure
= closure
;
1388 displaced
->step_original
= original
;
1389 displaced
->step_copy
= copy
;
1391 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1393 /* Resume execution at the copy. */
1394 regcache_write_pc (regcache
, copy
);
1396 discard_cleanups (ignore_cleanups
);
1398 do_cleanups (old_cleanups
);
1400 if (debug_displaced
)
1401 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1402 paddress (gdbarch
, copy
));
1408 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1409 const gdb_byte
*myaddr
, int len
)
1411 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1413 inferior_ptid
= ptid
;
1414 write_memory (memaddr
, myaddr
, len
);
1415 do_cleanups (ptid_cleanup
);
1418 /* Restore the contents of the copy area for thread PTID. */
1421 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1424 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1426 write_memory_ptid (ptid
, displaced
->step_copy
,
1427 displaced
->step_saved_copy
, len
);
1428 if (debug_displaced
)
1429 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1430 target_pid_to_str (ptid
),
1431 paddress (displaced
->step_gdbarch
,
1432 displaced
->step_copy
));
1436 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1438 struct cleanup
*old_cleanups
;
1439 struct displaced_step_inferior_state
*displaced
1440 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1442 /* Was any thread of this process doing a displaced step? */
1443 if (displaced
== NULL
)
1446 /* Was this event for the pid we displaced? */
1447 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1448 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1451 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1453 displaced_step_restore (displaced
, displaced
->step_ptid
);
1455 /* Did the instruction complete successfully? */
1456 if (signal
== GDB_SIGNAL_TRAP
)
1458 /* Fix up the resulting state. */
1459 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1460 displaced
->step_closure
,
1461 displaced
->step_original
,
1462 displaced
->step_copy
,
1463 get_thread_regcache (displaced
->step_ptid
));
1467 /* Since the instruction didn't complete, all we can do is
1469 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1470 CORE_ADDR pc
= regcache_read_pc (regcache
);
1472 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1473 regcache_write_pc (regcache
, pc
);
1476 do_cleanups (old_cleanups
);
1478 displaced
->step_ptid
= null_ptid
;
1480 /* Are there any pending displaced stepping requests? If so, run
1481 one now. Leave the state object around, since we're likely to
1482 need it again soon. */
1483 while (displaced
->step_request_queue
)
1485 struct displaced_step_request
*head
;
1487 struct regcache
*regcache
;
1488 struct gdbarch
*gdbarch
;
1489 CORE_ADDR actual_pc
;
1490 struct address_space
*aspace
;
1492 head
= displaced
->step_request_queue
;
1494 displaced
->step_request_queue
= head
->next
;
1497 context_switch (ptid
);
1499 regcache
= get_thread_regcache (ptid
);
1500 actual_pc
= regcache_read_pc (regcache
);
1501 aspace
= get_regcache_aspace (regcache
);
1503 if (breakpoint_here_p (aspace
, actual_pc
))
1505 if (debug_displaced
)
1506 fprintf_unfiltered (gdb_stdlog
,
1507 "displaced: stepping queued %s now\n",
1508 target_pid_to_str (ptid
));
1510 displaced_step_prepare (ptid
);
1512 gdbarch
= get_regcache_arch (regcache
);
1514 if (debug_displaced
)
1516 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
1519 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1520 paddress (gdbarch
, actual_pc
));
1521 read_memory (actual_pc
, buf
, sizeof (buf
));
1522 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1525 if (gdbarch_displaced_step_hw_singlestep (gdbarch
,
1526 displaced
->step_closure
))
1527 target_resume (ptid
, 1, GDB_SIGNAL_0
);
1529 target_resume (ptid
, 0, GDB_SIGNAL_0
);
1531 /* Done, we're stepping a thread. */
1537 struct thread_info
*tp
= inferior_thread ();
1539 /* The breakpoint we were sitting under has since been
1541 tp
->control
.trap_expected
= 0;
1543 /* Go back to what we were trying to do. */
1544 step
= currently_stepping (tp
);
1546 if (debug_displaced
)
1547 fprintf_unfiltered (gdb_stdlog
,
1548 "displaced: breakpoint is gone: %s, step(%d)\n",
1549 target_pid_to_str (tp
->ptid
), step
);
1551 target_resume (ptid
, step
, GDB_SIGNAL_0
);
1552 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1554 /* This request was discarded. See if there's any other
1555 thread waiting for its turn. */
1560 /* Update global variables holding ptids to hold NEW_PTID if they were
1561 holding OLD_PTID. */
1563 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1565 struct displaced_step_request
*it
;
1566 struct displaced_step_inferior_state
*displaced
;
1568 if (ptid_equal (inferior_ptid
, old_ptid
))
1569 inferior_ptid
= new_ptid
;
1571 if (ptid_equal (singlestep_ptid
, old_ptid
))
1572 singlestep_ptid
= new_ptid
;
1574 if (ptid_equal (deferred_step_ptid
, old_ptid
))
1575 deferred_step_ptid
= new_ptid
;
1577 for (displaced
= displaced_step_inferior_states
;
1579 displaced
= displaced
->next
)
1581 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
1582 displaced
->step_ptid
= new_ptid
;
1584 for (it
= displaced
->step_request_queue
; it
; it
= it
->next
)
1585 if (ptid_equal (it
->ptid
, old_ptid
))
1586 it
->ptid
= new_ptid
;
1593 /* Things to clean up if we QUIT out of resume (). */
1595 resume_cleanups (void *ignore
)
1600 static const char schedlock_off
[] = "off";
1601 static const char schedlock_on
[] = "on";
1602 static const char schedlock_step
[] = "step";
1603 static const char *const scheduler_enums
[] = {
1609 static const char *scheduler_mode
= schedlock_off
;
1611 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1612 struct cmd_list_element
*c
, const char *value
)
1614 fprintf_filtered (file
,
1615 _("Mode for locking scheduler "
1616 "during execution is \"%s\".\n"),
1621 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1623 if (!target_can_lock_scheduler
)
1625 scheduler_mode
= schedlock_off
;
1626 error (_("Target '%s' cannot support this command."), target_shortname
);
1630 /* True if execution commands resume all threads of all processes by
1631 default; otherwise, resume only threads of the current inferior
1633 int sched_multi
= 0;
1635 /* Try to setup for software single stepping over the specified location.
1636 Return 1 if target_resume() should use hardware single step.
1638 GDBARCH the current gdbarch.
1639 PC the location to step over. */
1642 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1646 if (execution_direction
== EXEC_FORWARD
1647 && gdbarch_software_single_step_p (gdbarch
)
1648 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1651 /* Do not pull these breakpoints until after a `wait' in
1652 `wait_for_inferior'. */
1653 singlestep_breakpoints_inserted_p
= 1;
1654 singlestep_ptid
= inferior_ptid
;
1660 /* Return a ptid representing the set of threads that we will proceed,
1661 in the perspective of the user/frontend. We may actually resume
1662 fewer threads at first, e.g., if a thread is stopped at a
1663 breakpoint that needs stepping-off, but that should not be visible
1664 to the user/frontend, and neither should the frontend/user be
1665 allowed to proceed any of the threads that happen to be stopped for
1666 internal run control handling, if a previous command wanted them
1670 user_visible_resume_ptid (int step
)
1672 /* By default, resume all threads of all processes. */
1673 ptid_t resume_ptid
= RESUME_ALL
;
1675 /* Maybe resume only all threads of the current process. */
1676 if (!sched_multi
&& target_supports_multi_process ())
1678 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
1681 /* Maybe resume a single thread after all. */
1684 /* With non-stop mode on, threads are always handled
1686 resume_ptid
= inferior_ptid
;
1688 else if ((scheduler_mode
== schedlock_on
)
1689 || (scheduler_mode
== schedlock_step
1690 && (step
|| singlestep_breakpoints_inserted_p
)))
1692 /* User-settable 'scheduler' mode requires solo thread resume. */
1693 resume_ptid
= inferior_ptid
;
1699 /* Resume the inferior, but allow a QUIT. This is useful if the user
1700 wants to interrupt some lengthy single-stepping operation
1701 (for child processes, the SIGINT goes to the inferior, and so
1702 we get a SIGINT random_signal, but for remote debugging and perhaps
1703 other targets, that's not true).
1705 STEP nonzero if we should step (zero to continue instead).
1706 SIG is the signal to give the inferior (zero for none). */
1708 resume (int step
, enum gdb_signal sig
)
1710 int should_resume
= 1;
1711 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
1712 struct regcache
*regcache
= get_current_regcache ();
1713 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1714 struct thread_info
*tp
= inferior_thread ();
1715 CORE_ADDR pc
= regcache_read_pc (regcache
);
1716 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1720 if (current_inferior ()->waiting_for_vfork_done
)
1722 /* Don't try to single-step a vfork parent that is waiting for
1723 the child to get out of the shared memory region (by exec'ing
1724 or exiting). This is particularly important on software
1725 single-step archs, as the child process would trip on the
1726 software single step breakpoint inserted for the parent
1727 process. Since the parent will not actually execute any
1728 instruction until the child is out of the shared region (such
1729 are vfork's semantics), it is safe to simply continue it.
1730 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
1731 the parent, and tell it to `keep_going', which automatically
1732 re-sets it stepping. */
1734 fprintf_unfiltered (gdb_stdlog
,
1735 "infrun: resume : clear step\n");
1740 fprintf_unfiltered (gdb_stdlog
,
1741 "infrun: resume (step=%d, signal=%d), "
1742 "trap_expected=%d, current thread [%s] at %s\n",
1743 step
, sig
, tp
->control
.trap_expected
,
1744 target_pid_to_str (inferior_ptid
),
1745 paddress (gdbarch
, pc
));
1747 /* Normally, by the time we reach `resume', the breakpoints are either
1748 removed or inserted, as appropriate. The exception is if we're sitting
1749 at a permanent breakpoint; we need to step over it, but permanent
1750 breakpoints can't be removed. So we have to test for it here. */
1751 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
1753 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
1754 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
1757 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1758 how to step past a permanent breakpoint on this architecture. Try using\n\
1759 a command like `return' or `jump' to continue execution."));
1762 /* If enabled, step over breakpoints by executing a copy of the
1763 instruction at a different address.
1765 We can't use displaced stepping when we have a signal to deliver;
1766 the comments for displaced_step_prepare explain why. The
1767 comments in the handle_inferior event for dealing with 'random
1768 signals' explain what we do instead.
1770 We can't use displaced stepping when we are waiting for vfork_done
1771 event, displaced stepping breaks the vfork child similarly as single
1772 step software breakpoint. */
1773 if (use_displaced_stepping (gdbarch
)
1774 && (tp
->control
.trap_expected
1775 || (step
&& gdbarch_software_single_step_p (gdbarch
)))
1776 && sig
== GDB_SIGNAL_0
1777 && !current_inferior ()->waiting_for_vfork_done
)
1779 struct displaced_step_inferior_state
*displaced
;
1781 if (!displaced_step_prepare (inferior_ptid
))
1783 /* Got placed in displaced stepping queue. Will be resumed
1784 later when all the currently queued displaced stepping
1785 requests finish. The thread is not executing at this point,
1786 and the call to set_executing will be made later. But we
1787 need to call set_running here, since from frontend point of view,
1788 the thread is running. */
1789 set_running (inferior_ptid
, 1);
1790 discard_cleanups (old_cleanups
);
1794 /* Update pc to reflect the new address from which we will execute
1795 instructions due to displaced stepping. */
1796 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
1798 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1799 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
1800 displaced
->step_closure
);
1803 /* Do we need to do it the hard way, w/temp breakpoints? */
1805 step
= maybe_software_singlestep (gdbarch
, pc
);
1807 /* Currently, our software single-step implementation leads to different
1808 results than hardware single-stepping in one situation: when stepping
1809 into delivering a signal which has an associated signal handler,
1810 hardware single-step will stop at the first instruction of the handler,
1811 while software single-step will simply skip execution of the handler.
1813 For now, this difference in behavior is accepted since there is no
1814 easy way to actually implement single-stepping into a signal handler
1815 without kernel support.
1817 However, there is one scenario where this difference leads to follow-on
1818 problems: if we're stepping off a breakpoint by removing all breakpoints
1819 and then single-stepping. In this case, the software single-step
1820 behavior means that even if there is a *breakpoint* in the signal
1821 handler, GDB still would not stop.
1823 Fortunately, we can at least fix this particular issue. We detect
1824 here the case where we are about to deliver a signal while software
1825 single-stepping with breakpoints removed. In this situation, we
1826 revert the decisions to remove all breakpoints and insert single-
1827 step breakpoints, and instead we install a step-resume breakpoint
1828 at the current address, deliver the signal without stepping, and
1829 once we arrive back at the step-resume breakpoint, actually step
1830 over the breakpoint we originally wanted to step over. */
1831 if (singlestep_breakpoints_inserted_p
1832 && tp
->control
.trap_expected
&& sig
!= GDB_SIGNAL_0
)
1834 /* If we have nested signals or a pending signal is delivered
1835 immediately after a handler returns, might might already have
1836 a step-resume breakpoint set on the earlier handler. We cannot
1837 set another step-resume breakpoint; just continue on until the
1838 original breakpoint is hit. */
1839 if (tp
->control
.step_resume_breakpoint
== NULL
)
1841 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
1842 tp
->step_after_step_resume_breakpoint
= 1;
1845 remove_single_step_breakpoints ();
1846 singlestep_breakpoints_inserted_p
= 0;
1848 insert_breakpoints ();
1849 tp
->control
.trap_expected
= 0;
1856 /* If STEP is set, it's a request to use hardware stepping
1857 facilities. But in that case, we should never
1858 use singlestep breakpoint. */
1859 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1861 /* Decide the set of threads to ask the target to resume. Start
1862 by assuming everything will be resumed, than narrow the set
1863 by applying increasingly restricting conditions. */
1864 resume_ptid
= user_visible_resume_ptid (step
);
1866 /* Maybe resume a single thread after all. */
1867 if (singlestep_breakpoints_inserted_p
1868 && stepping_past_singlestep_breakpoint
)
1870 /* The situation here is as follows. In thread T1 we wanted to
1871 single-step. Lacking hardware single-stepping we've
1872 set breakpoint at the PC of the next instruction -- call it
1873 P. After resuming, we've hit that breakpoint in thread T2.
1874 Now we've removed original breakpoint, inserted breakpoint
1875 at P+1, and try to step to advance T2 past breakpoint.
1876 We need to step only T2, as if T1 is allowed to freely run,
1877 it can run past P, and if other threads are allowed to run,
1878 they can hit breakpoint at P+1, and nested hits of single-step
1879 breakpoints is not something we'd want -- that's complicated
1880 to support, and has no value. */
1881 resume_ptid
= inferior_ptid
;
1883 else if ((step
|| singlestep_breakpoints_inserted_p
)
1884 && tp
->control
.trap_expected
)
1886 /* We're allowing a thread to run past a breakpoint it has
1887 hit, by single-stepping the thread with the breakpoint
1888 removed. In which case, we need to single-step only this
1889 thread, and keep others stopped, as they can miss this
1890 breakpoint if allowed to run.
1892 The current code actually removes all breakpoints when
1893 doing this, not just the one being stepped over, so if we
1894 let other threads run, we can actually miss any
1895 breakpoint, not just the one at PC. */
1896 resume_ptid
= inferior_ptid
;
1899 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1901 /* Most targets can step a breakpoint instruction, thus
1902 executing it normally. But if this one cannot, just
1903 continue and we will hit it anyway. */
1904 if (step
&& breakpoint_inserted_here_p (aspace
, pc
))
1909 && use_displaced_stepping (gdbarch
)
1910 && tp
->control
.trap_expected
)
1912 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1913 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
1914 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1917 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1918 paddress (resume_gdbarch
, actual_pc
));
1919 read_memory (actual_pc
, buf
, sizeof (buf
));
1920 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1923 /* Install inferior's terminal modes. */
1924 target_terminal_inferior ();
1926 /* Avoid confusing the next resume, if the next stop/resume
1927 happens to apply to another thread. */
1928 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1930 /* Advise target which signals may be handled silently. If we have
1931 removed breakpoints because we are stepping over one (which can
1932 happen only if we are not using displaced stepping), we need to
1933 receive all signals to avoid accidentally skipping a breakpoint
1934 during execution of a signal handler. */
1935 if ((step
|| singlestep_breakpoints_inserted_p
)
1936 && tp
->control
.trap_expected
1937 && !use_displaced_stepping (gdbarch
))
1938 target_pass_signals (0, NULL
);
1940 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
1942 target_resume (resume_ptid
, step
, sig
);
1945 discard_cleanups (old_cleanups
);
1950 /* Clear out all variables saying what to do when inferior is continued.
1951 First do this, then set the ones you want, then call `proceed'. */
1954 clear_proceed_status_thread (struct thread_info
*tp
)
1957 fprintf_unfiltered (gdb_stdlog
,
1958 "infrun: clear_proceed_status_thread (%s)\n",
1959 target_pid_to_str (tp
->ptid
));
1961 tp
->control
.trap_expected
= 0;
1962 tp
->control
.step_range_start
= 0;
1963 tp
->control
.step_range_end
= 0;
1964 tp
->control
.step_frame_id
= null_frame_id
;
1965 tp
->control
.step_stack_frame_id
= null_frame_id
;
1966 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1967 tp
->stop_requested
= 0;
1969 tp
->control
.stop_step
= 0;
1971 tp
->control
.proceed_to_finish
= 0;
1973 /* Discard any remaining commands or status from previous stop. */
1974 bpstat_clear (&tp
->control
.stop_bpstat
);
1978 clear_proceed_status_callback (struct thread_info
*tp
, void *data
)
1980 if (is_exited (tp
->ptid
))
1983 clear_proceed_status_thread (tp
);
1988 clear_proceed_status (void)
1992 /* In all-stop mode, delete the per-thread status of all
1993 threads, even if inferior_ptid is null_ptid, there may be
1994 threads on the list. E.g., we may be launching a new
1995 process, while selecting the executable. */
1996 iterate_over_threads (clear_proceed_status_callback
, NULL
);
1999 if (!ptid_equal (inferior_ptid
, null_ptid
))
2001 struct inferior
*inferior
;
2005 /* If in non-stop mode, only delete the per-thread status of
2006 the current thread. */
2007 clear_proceed_status_thread (inferior_thread ());
2010 inferior
= current_inferior ();
2011 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2014 stop_after_trap
= 0;
2016 observer_notify_about_to_proceed ();
2020 regcache_xfree (stop_registers
);
2021 stop_registers
= NULL
;
2025 /* Check the current thread against the thread that reported the most recent
2026 event. If a step-over is required return TRUE and set the current thread
2027 to the old thread. Otherwise return FALSE.
2029 This should be suitable for any targets that support threads. */
2032 prepare_to_proceed (int step
)
2035 struct target_waitstatus wait_status
;
2036 int schedlock_enabled
;
2038 /* With non-stop mode on, threads are always handled individually. */
2039 gdb_assert (! non_stop
);
2041 /* Get the last target status returned by target_wait(). */
2042 get_last_target_status (&wait_ptid
, &wait_status
);
2044 /* Make sure we were stopped at a breakpoint. */
2045 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
2046 || (wait_status
.value
.sig
!= GDB_SIGNAL_TRAP
2047 && wait_status
.value
.sig
!= GDB_SIGNAL_ILL
2048 && wait_status
.value
.sig
!= GDB_SIGNAL_SEGV
2049 && wait_status
.value
.sig
!= GDB_SIGNAL_EMT
))
2054 schedlock_enabled
= (scheduler_mode
== schedlock_on
2055 || (scheduler_mode
== schedlock_step
2058 /* Don't switch over to WAIT_PTID if scheduler locking is on. */
2059 if (schedlock_enabled
)
2062 /* Don't switch over if we're about to resume some other process
2063 other than WAIT_PTID's, and schedule-multiple is off. */
2065 && ptid_get_pid (wait_ptid
) != ptid_get_pid (inferior_ptid
))
2068 /* Switched over from WAIT_PID. */
2069 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
2070 && !ptid_equal (inferior_ptid
, wait_ptid
))
2072 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
2074 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2075 regcache_read_pc (regcache
)))
2077 /* If stepping, remember current thread to switch back to. */
2079 deferred_step_ptid
= inferior_ptid
;
2081 /* Switch back to WAIT_PID thread. */
2082 switch_to_thread (wait_ptid
);
2085 fprintf_unfiltered (gdb_stdlog
,
2086 "infrun: prepare_to_proceed (step=%d), "
2087 "switched to [%s]\n",
2088 step
, target_pid_to_str (inferior_ptid
));
2090 /* We return 1 to indicate that there is a breakpoint here,
2091 so we need to step over it before continuing to avoid
2092 hitting it straight away. */
2100 /* Basic routine for continuing the program in various fashions.
2102 ADDR is the address to resume at, or -1 for resume where stopped.
2103 SIGGNAL is the signal to give it, or 0 for none,
2104 or -1 for act according to how it stopped.
2105 STEP is nonzero if should trap after one instruction.
2106 -1 means return after that and print nothing.
2107 You should probably set various step_... variables
2108 before calling here, if you are stepping.
2110 You should call clear_proceed_status before calling proceed. */
2113 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
, int step
)
2115 struct regcache
*regcache
;
2116 struct gdbarch
*gdbarch
;
2117 struct thread_info
*tp
;
2119 struct address_space
*aspace
;
2122 /* If we're stopped at a fork/vfork, follow the branch set by the
2123 "set follow-fork-mode" command; otherwise, we'll just proceed
2124 resuming the current thread. */
2125 if (!follow_fork ())
2127 /* The target for some reason decided not to resume. */
2129 if (target_can_async_p ())
2130 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2134 /* We'll update this if & when we switch to a new thread. */
2135 previous_inferior_ptid
= inferior_ptid
;
2137 regcache
= get_current_regcache ();
2138 gdbarch
= get_regcache_arch (regcache
);
2139 aspace
= get_regcache_aspace (regcache
);
2140 pc
= regcache_read_pc (regcache
);
2143 step_start_function
= find_pc_function (pc
);
2145 stop_after_trap
= 1;
2147 if (addr
== (CORE_ADDR
) -1)
2149 if (pc
== stop_pc
&& breakpoint_here_p (aspace
, pc
)
2150 && execution_direction
!= EXEC_REVERSE
)
2151 /* There is a breakpoint at the address we will resume at,
2152 step one instruction before inserting breakpoints so that
2153 we do not stop right away (and report a second hit at this
2156 Note, we don't do this in reverse, because we won't
2157 actually be executing the breakpoint insn anyway.
2158 We'll be (un-)executing the previous instruction. */
2161 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2162 && gdbarch_single_step_through_delay (gdbarch
,
2163 get_current_frame ()))
2164 /* We stepped onto an instruction that needs to be stepped
2165 again before re-inserting the breakpoint, do so. */
2170 regcache_write_pc (regcache
, addr
);
2174 fprintf_unfiltered (gdb_stdlog
,
2175 "infrun: proceed (addr=%s, signal=%d, step=%d)\n",
2176 paddress (gdbarch
, addr
), siggnal
, step
);
2179 /* In non-stop, each thread is handled individually. The context
2180 must already be set to the right thread here. */
2184 /* In a multi-threaded task we may select another thread and
2185 then continue or step.
2187 But if the old thread was stopped at a breakpoint, it will
2188 immediately cause another breakpoint stop without any
2189 execution (i.e. it will report a breakpoint hit incorrectly).
2190 So we must step over it first.
2192 prepare_to_proceed checks the current thread against the
2193 thread that reported the most recent event. If a step-over
2194 is required it returns TRUE and sets the current thread to
2196 if (prepare_to_proceed (step
))
2200 /* prepare_to_proceed may change the current thread. */
2201 tp
= inferior_thread ();
2205 tp
->control
.trap_expected
= 1;
2206 /* If displaced stepping is enabled, we can step over the
2207 breakpoint without hitting it, so leave all breakpoints
2208 inserted. Otherwise we need to disable all breakpoints, step
2209 one instruction, and then re-add them when that step is
2211 if (!use_displaced_stepping (gdbarch
))
2212 remove_breakpoints ();
2215 /* We can insert breakpoints if we're not trying to step over one,
2216 or if we are stepping over one but we're using displaced stepping
2218 if (! tp
->control
.trap_expected
|| use_displaced_stepping (gdbarch
))
2219 insert_breakpoints ();
2223 /* Pass the last stop signal to the thread we're resuming,
2224 irrespective of whether the current thread is the thread that
2225 got the last event or not. This was historically GDB's
2226 behaviour before keeping a stop_signal per thread. */
2228 struct thread_info
*last_thread
;
2230 struct target_waitstatus last_status
;
2232 get_last_target_status (&last_ptid
, &last_status
);
2233 if (!ptid_equal (inferior_ptid
, last_ptid
)
2234 && !ptid_equal (last_ptid
, null_ptid
)
2235 && !ptid_equal (last_ptid
, minus_one_ptid
))
2237 last_thread
= find_thread_ptid (last_ptid
);
2240 tp
->suspend
.stop_signal
= last_thread
->suspend
.stop_signal
;
2241 last_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2246 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2247 tp
->suspend
.stop_signal
= siggnal
;
2248 /* If this signal should not be seen by program,
2249 give it zero. Used for debugging signals. */
2250 else if (!signal_program
[tp
->suspend
.stop_signal
])
2251 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2253 annotate_starting ();
2255 /* Make sure that output from GDB appears before output from the
2257 gdb_flush (gdb_stdout
);
2259 /* Refresh prev_pc value just prior to resuming. This used to be
2260 done in stop_stepping, however, setting prev_pc there did not handle
2261 scenarios such as inferior function calls or returning from
2262 a function via the return command. In those cases, the prev_pc
2263 value was not set properly for subsequent commands. The prev_pc value
2264 is used to initialize the starting line number in the ecs. With an
2265 invalid value, the gdb next command ends up stopping at the position
2266 represented by the next line table entry past our start position.
2267 On platforms that generate one line table entry per line, this
2268 is not a problem. However, on the ia64, the compiler generates
2269 extraneous line table entries that do not increase the line number.
2270 When we issue the gdb next command on the ia64 after an inferior call
2271 or a return command, we often end up a few instructions forward, still
2272 within the original line we started.
2274 An attempt was made to refresh the prev_pc at the same time the
2275 execution_control_state is initialized (for instance, just before
2276 waiting for an inferior event). But this approach did not work
2277 because of platforms that use ptrace, where the pc register cannot
2278 be read unless the inferior is stopped. At that point, we are not
2279 guaranteed the inferior is stopped and so the regcache_read_pc() call
2280 can fail. Setting the prev_pc value here ensures the value is updated
2281 correctly when the inferior is stopped. */
2282 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2284 /* Fill in with reasonable starting values. */
2285 init_thread_stepping_state (tp
);
2287 /* Reset to normal state. */
2288 init_infwait_state ();
2290 /* Resume inferior. */
2291 resume (oneproc
|| step
|| bpstat_should_step (), tp
->suspend
.stop_signal
);
2293 /* Wait for it to stop (if not standalone)
2294 and in any case decode why it stopped, and act accordingly. */
2295 /* Do this only if we are not using the event loop, or if the target
2296 does not support asynchronous execution. */
2297 if (!target_can_async_p ())
2299 wait_for_inferior ();
2305 /* Start remote-debugging of a machine over a serial link. */
2308 start_remote (int from_tty
)
2310 struct inferior
*inferior
;
2312 inferior
= current_inferior ();
2313 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
2315 /* Always go on waiting for the target, regardless of the mode. */
2316 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2317 indicate to wait_for_inferior that a target should timeout if
2318 nothing is returned (instead of just blocking). Because of this,
2319 targets expecting an immediate response need to, internally, set
2320 things up so that the target_wait() is forced to eventually
2322 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2323 differentiate to its caller what the state of the target is after
2324 the initial open has been performed. Here we're assuming that
2325 the target has stopped. It should be possible to eventually have
2326 target_open() return to the caller an indication that the target
2327 is currently running and GDB state should be set to the same as
2328 for an async run. */
2329 wait_for_inferior ();
2331 /* Now that the inferior has stopped, do any bookkeeping like
2332 loading shared libraries. We want to do this before normal_stop,
2333 so that the displayed frame is up to date. */
2334 post_create_inferior (¤t_target
, from_tty
);
2339 /* Initialize static vars when a new inferior begins. */
2342 init_wait_for_inferior (void)
2344 /* These are meaningless until the first time through wait_for_inferior. */
2346 breakpoint_init_inferior (inf_starting
);
2348 clear_proceed_status ();
2350 stepping_past_singlestep_breakpoint
= 0;
2351 deferred_step_ptid
= null_ptid
;
2353 target_last_wait_ptid
= minus_one_ptid
;
2355 previous_inferior_ptid
= inferior_ptid
;
2356 init_infwait_state ();
2358 /* Discard any skipped inlined frames. */
2359 clear_inline_frame_state (minus_one_ptid
);
2363 /* This enum encodes possible reasons for doing a target_wait, so that
2364 wfi can call target_wait in one place. (Ultimately the call will be
2365 moved out of the infinite loop entirely.) */
2369 infwait_normal_state
,
2370 infwait_thread_hop_state
,
2371 infwait_step_watch_state
,
2372 infwait_nonstep_watch_state
2375 /* The PTID we'll do a target_wait on.*/
2378 /* Current inferior wait state. */
2379 enum infwait_states infwait_state
;
2381 /* Data to be passed around while handling an event. This data is
2382 discarded between events. */
2383 struct execution_control_state
2386 /* The thread that got the event, if this was a thread event; NULL
2388 struct thread_info
*event_thread
;
2390 struct target_waitstatus ws
;
2392 int stop_func_filled_in
;
2393 CORE_ADDR stop_func_start
;
2394 CORE_ADDR stop_func_end
;
2395 const char *stop_func_name
;
2399 static void handle_inferior_event (struct execution_control_state
*ecs
);
2401 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2402 struct execution_control_state
*ecs
);
2403 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2404 struct execution_control_state
*ecs
);
2405 static void check_exception_resume (struct execution_control_state
*,
2406 struct frame_info
*);
2408 static void stop_stepping (struct execution_control_state
*ecs
);
2409 static void prepare_to_wait (struct execution_control_state
*ecs
);
2410 static void keep_going (struct execution_control_state
*ecs
);
2412 /* Callback for iterate over threads. If the thread is stopped, but
2413 the user/frontend doesn't know about that yet, go through
2414 normal_stop, as if the thread had just stopped now. ARG points at
2415 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2416 ptid_is_pid(PTID) is true, applies to all threads of the process
2417 pointed at by PTID. Otherwise, apply only to the thread pointed by
2421 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2423 ptid_t ptid
= * (ptid_t
*) arg
;
2425 if ((ptid_equal (info
->ptid
, ptid
)
2426 || ptid_equal (minus_one_ptid
, ptid
)
2427 || (ptid_is_pid (ptid
)
2428 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2429 && is_running (info
->ptid
)
2430 && !is_executing (info
->ptid
))
2432 struct cleanup
*old_chain
;
2433 struct execution_control_state ecss
;
2434 struct execution_control_state
*ecs
= &ecss
;
2436 memset (ecs
, 0, sizeof (*ecs
));
2438 old_chain
= make_cleanup_restore_current_thread ();
2440 switch_to_thread (info
->ptid
);
2442 /* Go through handle_inferior_event/normal_stop, so we always
2443 have consistent output as if the stop event had been
2445 ecs
->ptid
= info
->ptid
;
2446 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2447 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2448 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
2450 handle_inferior_event (ecs
);
2452 if (!ecs
->wait_some_more
)
2454 struct thread_info
*tp
;
2458 /* Finish off the continuations. */
2459 tp
= inferior_thread ();
2460 do_all_intermediate_continuations_thread (tp
, 1);
2461 do_all_continuations_thread (tp
, 1);
2464 do_cleanups (old_chain
);
2470 /* This function is attached as a "thread_stop_requested" observer.
2471 Cleanup local state that assumed the PTID was to be resumed, and
2472 report the stop to the frontend. */
2475 infrun_thread_stop_requested (ptid_t ptid
)
2477 struct displaced_step_inferior_state
*displaced
;
2479 /* PTID was requested to stop. Remove it from the displaced
2480 stepping queue, so we don't try to resume it automatically. */
2482 for (displaced
= displaced_step_inferior_states
;
2484 displaced
= displaced
->next
)
2486 struct displaced_step_request
*it
, **prev_next_p
;
2488 it
= displaced
->step_request_queue
;
2489 prev_next_p
= &displaced
->step_request_queue
;
2492 if (ptid_match (it
->ptid
, ptid
))
2494 *prev_next_p
= it
->next
;
2500 prev_next_p
= &it
->next
;
2507 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2511 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2513 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2514 nullify_last_target_wait_ptid ();
2517 /* Callback for iterate_over_threads. */
2520 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
2522 if (is_exited (info
->ptid
))
2525 delete_step_resume_breakpoint (info
);
2526 delete_exception_resume_breakpoint (info
);
2530 /* In all-stop, delete the step resume breakpoint of any thread that
2531 had one. In non-stop, delete the step resume breakpoint of the
2532 thread that just stopped. */
2535 delete_step_thread_step_resume_breakpoint (void)
2537 if (!target_has_execution
2538 || ptid_equal (inferior_ptid
, null_ptid
))
2539 /* If the inferior has exited, we have already deleted the step
2540 resume breakpoints out of GDB's lists. */
2545 /* If in non-stop mode, only delete the step-resume or
2546 longjmp-resume breakpoint of the thread that just stopped
2548 struct thread_info
*tp
= inferior_thread ();
2550 delete_step_resume_breakpoint (tp
);
2551 delete_exception_resume_breakpoint (tp
);
2554 /* In all-stop mode, delete all step-resume and longjmp-resume
2555 breakpoints of any thread that had them. */
2556 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
2559 /* A cleanup wrapper. */
2562 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
2564 delete_step_thread_step_resume_breakpoint ();
2567 /* Pretty print the results of target_wait, for debugging purposes. */
2570 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
2571 const struct target_waitstatus
*ws
)
2573 char *status_string
= target_waitstatus_to_string (ws
);
2574 struct ui_file
*tmp_stream
= mem_fileopen ();
2577 /* The text is split over several lines because it was getting too long.
2578 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2579 output as a unit; we want only one timestamp printed if debug_timestamp
2582 fprintf_unfiltered (tmp_stream
,
2583 "infrun: target_wait (%d", PIDGET (waiton_ptid
));
2584 if (PIDGET (waiton_ptid
) != -1)
2585 fprintf_unfiltered (tmp_stream
,
2586 " [%s]", target_pid_to_str (waiton_ptid
));
2587 fprintf_unfiltered (tmp_stream
, ", status) =\n");
2588 fprintf_unfiltered (tmp_stream
,
2589 "infrun: %d [%s],\n",
2590 PIDGET (result_ptid
), target_pid_to_str (result_ptid
));
2591 fprintf_unfiltered (tmp_stream
,
2595 text
= ui_file_xstrdup (tmp_stream
, NULL
);
2597 /* This uses %s in part to handle %'s in the text, but also to avoid
2598 a gcc error: the format attribute requires a string literal. */
2599 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
2601 xfree (status_string
);
2603 ui_file_delete (tmp_stream
);
2606 /* Prepare and stabilize the inferior for detaching it. E.g.,
2607 detaching while a thread is displaced stepping is a recipe for
2608 crashing it, as nothing would readjust the PC out of the scratch
2612 prepare_for_detach (void)
2614 struct inferior
*inf
= current_inferior ();
2615 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
2616 struct cleanup
*old_chain_1
;
2617 struct displaced_step_inferior_state
*displaced
;
2619 displaced
= get_displaced_stepping_state (inf
->pid
);
2621 /* Is any thread of this process displaced stepping? If not,
2622 there's nothing else to do. */
2623 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
2627 fprintf_unfiltered (gdb_stdlog
,
2628 "displaced-stepping in-process while detaching");
2630 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
2633 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
2635 struct cleanup
*old_chain_2
;
2636 struct execution_control_state ecss
;
2637 struct execution_control_state
*ecs
;
2640 memset (ecs
, 0, sizeof (*ecs
));
2642 overlay_cache_invalid
= 1;
2644 if (deprecated_target_wait_hook
)
2645 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
2647 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
2650 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
2652 /* If an error happens while handling the event, propagate GDB's
2653 knowledge of the executing state to the frontend/user running
2655 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
2658 /* In non-stop mode, each thread is handled individually.
2659 Switch early, so the global state is set correctly for this
2662 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2663 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2664 context_switch (ecs
->ptid
);
2666 /* Now figure out what to do with the result of the result. */
2667 handle_inferior_event (ecs
);
2669 /* No error, don't finish the state yet. */
2670 discard_cleanups (old_chain_2
);
2672 /* Breakpoints and watchpoints are not installed on the target
2673 at this point, and signals are passed directly to the
2674 inferior, so this must mean the process is gone. */
2675 if (!ecs
->wait_some_more
)
2677 discard_cleanups (old_chain_1
);
2678 error (_("Program exited while detaching"));
2682 discard_cleanups (old_chain_1
);
2685 /* Wait for control to return from inferior to debugger.
2687 If inferior gets a signal, we may decide to start it up again
2688 instead of returning. That is why there is a loop in this function.
2689 When this function actually returns it means the inferior
2690 should be left stopped and GDB should read more commands. */
2693 wait_for_inferior (void)
2695 struct cleanup
*old_cleanups
;
2699 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
2702 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
2706 struct execution_control_state ecss
;
2707 struct execution_control_state
*ecs
= &ecss
;
2708 struct cleanup
*old_chain
;
2710 memset (ecs
, 0, sizeof (*ecs
));
2712 overlay_cache_invalid
= 1;
2714 if (deprecated_target_wait_hook
)
2715 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
2717 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
2720 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2722 /* If an error happens while handling the event, propagate GDB's
2723 knowledge of the executing state to the frontend/user running
2725 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2727 /* Now figure out what to do with the result of the result. */
2728 handle_inferior_event (ecs
);
2730 /* No error, don't finish the state yet. */
2731 discard_cleanups (old_chain
);
2733 if (!ecs
->wait_some_more
)
2737 do_cleanups (old_cleanups
);
2740 /* Asynchronous version of wait_for_inferior. It is called by the
2741 event loop whenever a change of state is detected on the file
2742 descriptor corresponding to the target. It can be called more than
2743 once to complete a single execution command. In such cases we need
2744 to keep the state in a global variable ECSS. If it is the last time
2745 that this function is called for a single execution command, then
2746 report to the user that the inferior has stopped, and do the
2747 necessary cleanups. */
2750 fetch_inferior_event (void *client_data
)
2752 struct execution_control_state ecss
;
2753 struct execution_control_state
*ecs
= &ecss
;
2754 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
2755 struct cleanup
*ts_old_chain
;
2756 int was_sync
= sync_execution
;
2759 memset (ecs
, 0, sizeof (*ecs
));
2761 /* We're handling a live event, so make sure we're doing live
2762 debugging. If we're looking at traceframes while the target is
2763 running, we're going to need to get back to that mode after
2764 handling the event. */
2767 make_cleanup_restore_current_traceframe ();
2768 set_current_traceframe (-1);
2772 /* In non-stop mode, the user/frontend should not notice a thread
2773 switch due to internal events. Make sure we reverse to the
2774 user selected thread and frame after handling the event and
2775 running any breakpoint commands. */
2776 make_cleanup_restore_current_thread ();
2778 overlay_cache_invalid
= 1;
2780 make_cleanup_restore_integer (&execution_direction
);
2781 execution_direction
= target_execution_direction ();
2783 if (deprecated_target_wait_hook
)
2785 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2787 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2790 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2793 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
2794 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
2795 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2796 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2797 /* In non-stop mode, each thread is handled individually. Switch
2798 early, so the global state is set correctly for this
2800 context_switch (ecs
->ptid
);
2802 /* If an error happens while handling the event, propagate GDB's
2803 knowledge of the executing state to the frontend/user running
2806 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2808 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
2810 /* Get executed before make_cleanup_restore_current_thread above to apply
2811 still for the thread which has thrown the exception. */
2812 make_bpstat_clear_actions_cleanup ();
2814 /* Now figure out what to do with the result of the result. */
2815 handle_inferior_event (ecs
);
2817 if (!ecs
->wait_some_more
)
2819 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2821 delete_step_thread_step_resume_breakpoint ();
2823 /* We may not find an inferior if this was a process exit. */
2824 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
2827 if (target_has_execution
2828 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
2829 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2830 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2831 && ecs
->event_thread
->step_multi
2832 && ecs
->event_thread
->control
.stop_step
)
2833 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
2836 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2841 /* No error, don't finish the thread states yet. */
2842 discard_cleanups (ts_old_chain
);
2844 /* Revert thread and frame. */
2845 do_cleanups (old_chain
);
2847 /* If the inferior was in sync execution mode, and now isn't,
2848 restore the prompt (a synchronous execution command has finished,
2849 and we're ready for input). */
2850 if (interpreter_async
&& was_sync
&& !sync_execution
)
2851 display_gdb_prompt (0);
2855 && exec_done_display_p
2856 && (ptid_equal (inferior_ptid
, null_ptid
)
2857 || !is_running (inferior_ptid
)))
2858 printf_unfiltered (_("completed.\n"));
2861 /* Record the frame and location we're currently stepping through. */
2863 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
2865 struct thread_info
*tp
= inferior_thread ();
2867 tp
->control
.step_frame_id
= get_frame_id (frame
);
2868 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
2870 tp
->current_symtab
= sal
.symtab
;
2871 tp
->current_line
= sal
.line
;
2874 /* Clear context switchable stepping state. */
2877 init_thread_stepping_state (struct thread_info
*tss
)
2879 tss
->stepping_over_breakpoint
= 0;
2880 tss
->step_after_step_resume_breakpoint
= 0;
2883 /* Return the cached copy of the last pid/waitstatus returned by
2884 target_wait()/deprecated_target_wait_hook(). The data is actually
2885 cached by handle_inferior_event(), which gets called immediately
2886 after target_wait()/deprecated_target_wait_hook(). */
2889 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
2891 *ptidp
= target_last_wait_ptid
;
2892 *status
= target_last_waitstatus
;
2896 nullify_last_target_wait_ptid (void)
2898 target_last_wait_ptid
= minus_one_ptid
;
2901 /* Switch thread contexts. */
2904 context_switch (ptid_t ptid
)
2906 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
2908 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
2909 target_pid_to_str (inferior_ptid
));
2910 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
2911 target_pid_to_str (ptid
));
2914 switch_to_thread (ptid
);
2918 adjust_pc_after_break (struct execution_control_state
*ecs
)
2920 struct regcache
*regcache
;
2921 struct gdbarch
*gdbarch
;
2922 struct address_space
*aspace
;
2923 CORE_ADDR breakpoint_pc
;
2925 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2926 we aren't, just return.
2928 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2929 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2930 implemented by software breakpoints should be handled through the normal
2933 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2934 different signals (SIGILL or SIGEMT for instance), but it is less
2935 clear where the PC is pointing afterwards. It may not match
2936 gdbarch_decr_pc_after_break. I don't know any specific target that
2937 generates these signals at breakpoints (the code has been in GDB since at
2938 least 1992) so I can not guess how to handle them here.
2940 In earlier versions of GDB, a target with
2941 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2942 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2943 target with both of these set in GDB history, and it seems unlikely to be
2944 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2946 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
2949 if (ecs
->ws
.value
.sig
!= GDB_SIGNAL_TRAP
)
2952 /* In reverse execution, when a breakpoint is hit, the instruction
2953 under it has already been de-executed. The reported PC always
2954 points at the breakpoint address, so adjusting it further would
2955 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2958 B1 0x08000000 : INSN1
2959 B2 0x08000001 : INSN2
2961 PC -> 0x08000003 : INSN4
2963 Say you're stopped at 0x08000003 as above. Reverse continuing
2964 from that point should hit B2 as below. Reading the PC when the
2965 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2966 been de-executed already.
2968 B1 0x08000000 : INSN1
2969 B2 PC -> 0x08000001 : INSN2
2973 We can't apply the same logic as for forward execution, because
2974 we would wrongly adjust the PC to 0x08000000, since there's a
2975 breakpoint at PC - 1. We'd then report a hit on B1, although
2976 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2978 if (execution_direction
== EXEC_REVERSE
)
2981 /* If this target does not decrement the PC after breakpoints, then
2982 we have nothing to do. */
2983 regcache
= get_thread_regcache (ecs
->ptid
);
2984 gdbarch
= get_regcache_arch (regcache
);
2985 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
2988 aspace
= get_regcache_aspace (regcache
);
2990 /* Find the location where (if we've hit a breakpoint) the
2991 breakpoint would be. */
2992 breakpoint_pc
= regcache_read_pc (regcache
)
2993 - gdbarch_decr_pc_after_break (gdbarch
);
2995 /* Check whether there actually is a software breakpoint inserted at
2998 If in non-stop mode, a race condition is possible where we've
2999 removed a breakpoint, but stop events for that breakpoint were
3000 already queued and arrive later. To suppress those spurious
3001 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3002 and retire them after a number of stop events are reported. */
3003 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3004 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3006 struct cleanup
*old_cleanups
= NULL
;
3009 old_cleanups
= record_gdb_operation_disable_set ();
3011 /* When using hardware single-step, a SIGTRAP is reported for both
3012 a completed single-step and a software breakpoint. Need to
3013 differentiate between the two, as the latter needs adjusting
3014 but the former does not.
3016 The SIGTRAP can be due to a completed hardware single-step only if
3017 - we didn't insert software single-step breakpoints
3018 - the thread to be examined is still the current thread
3019 - this thread is currently being stepped
3021 If any of these events did not occur, we must have stopped due
3022 to hitting a software breakpoint, and have to back up to the
3025 As a special case, we could have hardware single-stepped a
3026 software breakpoint. In this case (prev_pc == breakpoint_pc),
3027 we also need to back up to the breakpoint address. */
3029 if (singlestep_breakpoints_inserted_p
3030 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
3031 || !currently_stepping (ecs
->event_thread
)
3032 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
3033 regcache_write_pc (regcache
, breakpoint_pc
);
3036 do_cleanups (old_cleanups
);
3041 init_infwait_state (void)
3043 waiton_ptid
= pid_to_ptid (-1);
3044 infwait_state
= infwait_normal_state
;
3048 error_is_running (void)
3050 error (_("Cannot execute this command while "
3051 "the selected thread is running."));
3055 ensure_not_running (void)
3057 if (is_running (inferior_ptid
))
3058 error_is_running ();
3062 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3064 for (frame
= get_prev_frame (frame
);
3066 frame
= get_prev_frame (frame
))
3068 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3070 if (get_frame_type (frame
) != INLINE_FRAME
)
3077 /* Auxiliary function that handles syscall entry/return events.
3078 It returns 1 if the inferior should keep going (and GDB
3079 should ignore the event), or 0 if the event deserves to be
3083 handle_syscall_event (struct execution_control_state
*ecs
)
3085 struct regcache
*regcache
;
3086 struct gdbarch
*gdbarch
;
3089 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3090 context_switch (ecs
->ptid
);
3092 regcache
= get_thread_regcache (ecs
->ptid
);
3093 gdbarch
= get_regcache_arch (regcache
);
3094 syscall_number
= ecs
->ws
.value
.syscall_number
;
3095 stop_pc
= regcache_read_pc (regcache
);
3097 if (catch_syscall_enabled () > 0
3098 && catching_syscall_number (syscall_number
) > 0)
3101 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3104 ecs
->event_thread
->control
.stop_bpstat
3105 = bpstat_stop_status (get_regcache_aspace (regcache
),
3106 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3108 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3110 if (!ecs
->random_signal
)
3112 /* Catchpoint hit. */
3113 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3118 /* If no catchpoint triggered for this, then keep going. */
3119 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3124 /* Clear the supplied execution_control_state's stop_func_* fields. */
3127 clear_stop_func (struct execution_control_state
*ecs
)
3129 ecs
->stop_func_filled_in
= 0;
3130 ecs
->stop_func_start
= 0;
3131 ecs
->stop_func_end
= 0;
3132 ecs
->stop_func_name
= NULL
;
3135 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3138 fill_in_stop_func (struct gdbarch
*gdbarch
,
3139 struct execution_control_state
*ecs
)
3141 if (!ecs
->stop_func_filled_in
)
3143 /* Don't care about return value; stop_func_start and stop_func_name
3144 will both be 0 if it doesn't work. */
3145 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3146 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3147 ecs
->stop_func_start
3148 += gdbarch_deprecated_function_start_offset (gdbarch
);
3150 ecs
->stop_func_filled_in
= 1;
3154 /* Given an execution control state that has been freshly filled in
3155 by an event from the inferior, figure out what it means and take
3156 appropriate action. */
3159 handle_inferior_event (struct execution_control_state
*ecs
)
3161 struct frame_info
*frame
;
3162 struct gdbarch
*gdbarch
;
3163 int stopped_by_watchpoint
;
3164 int stepped_after_stopped_by_watchpoint
= 0;
3165 struct symtab_and_line stop_pc_sal
;
3166 enum stop_kind stop_soon
;
3168 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3170 /* We had an event in the inferior, but we are not interested in
3171 handling it at this level. The lower layers have already
3172 done what needs to be done, if anything.
3174 One of the possible circumstances for this is when the
3175 inferior produces output for the console. The inferior has
3176 not stopped, and we are ignoring the event. Another possible
3177 circumstance is any event which the lower level knows will be
3178 reported multiple times without an intervening resume. */
3180 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3181 prepare_to_wait (ecs
);
3185 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3186 && target_can_async_p () && !sync_execution
)
3188 /* There were no unwaited-for children left in the target, but,
3189 we're not synchronously waiting for events either. Just
3190 ignore. Otherwise, if we were running a synchronous
3191 execution command, we need to cancel it and give the user
3192 back the terminal. */
3194 fprintf_unfiltered (gdb_stdlog
,
3195 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3196 prepare_to_wait (ecs
);
3200 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3201 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3202 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
3204 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3207 stop_soon
= inf
->control
.stop_soon
;
3210 stop_soon
= NO_STOP_QUIETLY
;
3212 /* Cache the last pid/waitstatus. */
3213 target_last_wait_ptid
= ecs
->ptid
;
3214 target_last_waitstatus
= ecs
->ws
;
3216 /* Always clear state belonging to the previous time we stopped. */
3217 stop_stack_dummy
= STOP_NONE
;
3219 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3221 /* No unwaited-for children left. IOW, all resumed children
3224 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3226 stop_print_frame
= 0;
3227 stop_stepping (ecs
);
3231 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3232 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3233 && !ptid_equal (ecs
->ptid
, minus_one_ptid
))
3235 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3236 /* If it's a new thread, add it to the thread database. */
3237 if (ecs
->event_thread
== NULL
)
3238 ecs
->event_thread
= add_thread (ecs
->ptid
);
3241 /* Dependent on valid ECS->EVENT_THREAD. */
3242 adjust_pc_after_break (ecs
);
3244 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3245 reinit_frame_cache ();
3247 breakpoint_retire_moribund ();
3249 /* First, distinguish signals caused by the debugger from signals
3250 that have to do with the program's own actions. Note that
3251 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3252 on the operating system version. Here we detect when a SIGILL or
3253 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3254 something similar for SIGSEGV, since a SIGSEGV will be generated
3255 when we're trying to execute a breakpoint instruction on a
3256 non-executable stack. This happens for call dummy breakpoints
3257 for architectures like SPARC that place call dummies on the
3259 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3260 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3261 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3262 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3264 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3266 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3267 regcache_read_pc (regcache
)))
3270 fprintf_unfiltered (gdb_stdlog
,
3271 "infrun: Treating signal as SIGTRAP\n");
3272 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3276 /* Mark the non-executing threads accordingly. In all-stop, all
3277 threads of all processes are stopped when we get any event
3278 reported. In non-stop mode, only the event thread stops. If
3279 we're handling a process exit in non-stop mode, there's nothing
3280 to do, as threads of the dead process are gone, and threads of
3281 any other process were left running. */
3283 set_executing (minus_one_ptid
, 0);
3284 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3285 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3286 set_executing (ecs
->ptid
, 0);
3288 switch (infwait_state
)
3290 case infwait_thread_hop_state
:
3292 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
3295 case infwait_normal_state
:
3297 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
3300 case infwait_step_watch_state
:
3302 fprintf_unfiltered (gdb_stdlog
,
3303 "infrun: infwait_step_watch_state\n");
3305 stepped_after_stopped_by_watchpoint
= 1;
3308 case infwait_nonstep_watch_state
:
3310 fprintf_unfiltered (gdb_stdlog
,
3311 "infrun: infwait_nonstep_watch_state\n");
3312 insert_breakpoints ();
3314 /* FIXME-maybe: is this cleaner than setting a flag? Does it
3315 handle things like signals arriving and other things happening
3316 in combination correctly? */
3317 stepped_after_stopped_by_watchpoint
= 1;
3321 internal_error (__FILE__
, __LINE__
, _("bad switch"));
3324 infwait_state
= infwait_normal_state
;
3325 waiton_ptid
= pid_to_ptid (-1);
3327 switch (ecs
->ws
.kind
)
3329 case TARGET_WAITKIND_LOADED
:
3331 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3332 /* Ignore gracefully during startup of the inferior, as it might
3333 be the shell which has just loaded some objects, otherwise
3334 add the symbols for the newly loaded objects. Also ignore at
3335 the beginning of an attach or remote session; we will query
3336 the full list of libraries once the connection is
3338 if (stop_soon
== NO_STOP_QUIETLY
)
3340 struct regcache
*regcache
;
3342 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3343 context_switch (ecs
->ptid
);
3344 regcache
= get_thread_regcache (ecs
->ptid
);
3346 handle_solib_event ();
3348 ecs
->event_thread
->control
.stop_bpstat
3349 = bpstat_stop_status (get_regcache_aspace (regcache
),
3350 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3352 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3354 if (!ecs
->random_signal
)
3356 /* A catchpoint triggered. */
3357 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3358 goto process_event_stop_test
;
3361 /* If requested, stop when the dynamic linker notifies
3362 gdb of events. This allows the user to get control
3363 and place breakpoints in initializer routines for
3364 dynamically loaded objects (among other things). */
3365 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3366 if (stop_on_solib_events
)
3368 /* Make sure we print "Stopped due to solib-event" in
3370 stop_print_frame
= 1;
3372 stop_stepping (ecs
);
3377 /* If we are skipping through a shell, or through shared library
3378 loading that we aren't interested in, resume the program. If
3379 we're running the program normally, also resume. But stop if
3380 we're attaching or setting up a remote connection. */
3381 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3383 /* Loading of shared libraries might have changed breakpoint
3384 addresses. Make sure new breakpoints are inserted. */
3385 if (stop_soon
== NO_STOP_QUIETLY
3386 && !breakpoints_always_inserted_mode ())
3387 insert_breakpoints ();
3388 resume (0, GDB_SIGNAL_0
);
3389 prepare_to_wait (ecs
);
3395 case TARGET_WAITKIND_SPURIOUS
:
3397 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3398 resume (0, GDB_SIGNAL_0
);
3399 prepare_to_wait (ecs
);
3402 case TARGET_WAITKIND_EXITED
:
3404 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
3405 inferior_ptid
= ecs
->ptid
;
3406 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3407 set_current_program_space (current_inferior ()->pspace
);
3408 handle_vfork_child_exec_or_exit (0);
3409 target_terminal_ours (); /* Must do this before mourn anyway. */
3410 print_exited_reason (ecs
->ws
.value
.integer
);
3412 /* Record the exit code in the convenience variable $_exitcode, so
3413 that the user can inspect this again later. */
3414 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3415 (LONGEST
) ecs
->ws
.value
.integer
);
3417 /* Also record this in the inferior itself. */
3418 current_inferior ()->has_exit_code
= 1;
3419 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3421 gdb_flush (gdb_stdout
);
3422 target_mourn_inferior ();
3423 singlestep_breakpoints_inserted_p
= 0;
3424 cancel_single_step_breakpoints ();
3425 stop_print_frame
= 0;
3426 stop_stepping (ecs
);
3429 case TARGET_WAITKIND_SIGNALLED
:
3431 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
3432 inferior_ptid
= ecs
->ptid
;
3433 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3434 set_current_program_space (current_inferior ()->pspace
);
3435 handle_vfork_child_exec_or_exit (0);
3436 stop_print_frame
= 0;
3437 target_terminal_ours (); /* Must do this before mourn anyway. */
3439 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
3440 reach here unless the inferior is dead. However, for years
3441 target_kill() was called here, which hints that fatal signals aren't
3442 really fatal on some systems. If that's true, then some changes
3444 target_mourn_inferior ();
3446 print_signal_exited_reason (ecs
->ws
.value
.sig
);
3447 singlestep_breakpoints_inserted_p
= 0;
3448 cancel_single_step_breakpoints ();
3449 stop_stepping (ecs
);
3452 /* The following are the only cases in which we keep going;
3453 the above cases end in a continue or goto. */
3454 case TARGET_WAITKIND_FORKED
:
3455 case TARGET_WAITKIND_VFORKED
:
3457 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3459 /* Check whether the inferior is displaced stepping. */
3461 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3462 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3463 struct displaced_step_inferior_state
*displaced
3464 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3466 /* If checking displaced stepping is supported, and thread
3467 ecs->ptid is displaced stepping. */
3468 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3470 struct inferior
*parent_inf
3471 = find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3472 struct regcache
*child_regcache
;
3473 CORE_ADDR parent_pc
;
3475 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3476 indicating that the displaced stepping of syscall instruction
3477 has been done. Perform cleanup for parent process here. Note
3478 that this operation also cleans up the child process for vfork,
3479 because their pages are shared. */
3480 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
3482 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3484 /* Restore scratch pad for child process. */
3485 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3488 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3489 the child's PC is also within the scratchpad. Set the child's PC
3490 to the parent's PC value, which has already been fixed up.
3491 FIXME: we use the parent's aspace here, although we're touching
3492 the child, because the child hasn't been added to the inferior
3493 list yet at this point. */
3496 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3498 parent_inf
->aspace
);
3499 /* Read PC value of parent process. */
3500 parent_pc
= regcache_read_pc (regcache
);
3502 if (debug_displaced
)
3503 fprintf_unfiltered (gdb_stdlog
,
3504 "displaced: write child pc from %s to %s\n",
3506 regcache_read_pc (child_regcache
)),
3507 paddress (gdbarch
, parent_pc
));
3509 regcache_write_pc (child_regcache
, parent_pc
);
3513 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3515 context_switch (ecs
->ptid
);
3516 reinit_frame_cache ();
3519 /* Immediately detach breakpoints from the child before there's
3520 any chance of letting the user delete breakpoints from the
3521 breakpoint lists. If we don't do this early, it's easy to
3522 leave left over traps in the child, vis: "break foo; catch
3523 fork; c; <fork>; del; c; <child calls foo>". We only follow
3524 the fork on the last `continue', and by that time the
3525 breakpoint at "foo" is long gone from the breakpoint table.
3526 If we vforked, then we don't need to unpatch here, since both
3527 parent and child are sharing the same memory pages; we'll
3528 need to unpatch at follow/detach time instead to be certain
3529 that new breakpoints added between catchpoint hit time and
3530 vfork follow are detached. */
3531 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3533 int child_pid
= ptid_get_pid (ecs
->ws
.value
.related_pid
);
3535 /* This won't actually modify the breakpoint list, but will
3536 physically remove the breakpoints from the child. */
3537 detach_breakpoints (child_pid
);
3540 if (singlestep_breakpoints_inserted_p
)
3542 /* Pull the single step breakpoints out of the target. */
3543 remove_single_step_breakpoints ();
3544 singlestep_breakpoints_inserted_p
= 0;
3547 /* In case the event is caught by a catchpoint, remember that
3548 the event is to be followed at the next resume of the thread,
3549 and not immediately. */
3550 ecs
->event_thread
->pending_follow
= ecs
->ws
;
3552 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3554 ecs
->event_thread
->control
.stop_bpstat
3555 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3556 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3558 /* Note that we're interested in knowing the bpstat actually
3559 causes a stop, not just if it may explain the signal.
3560 Software watchpoints, for example, always appear in the
3563 = !bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
);
3565 /* If no catchpoint triggered for this, then keep going. */
3566 if (ecs
->random_signal
)
3572 = (follow_fork_mode_string
== follow_fork_mode_child
);
3574 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3576 should_resume
= follow_fork ();
3579 child
= ecs
->ws
.value
.related_pid
;
3581 /* In non-stop mode, also resume the other branch. */
3582 if (non_stop
&& !detach_fork
)
3585 switch_to_thread (parent
);
3587 switch_to_thread (child
);
3589 ecs
->event_thread
= inferior_thread ();
3590 ecs
->ptid
= inferior_ptid
;
3595 switch_to_thread (child
);
3597 switch_to_thread (parent
);
3599 ecs
->event_thread
= inferior_thread ();
3600 ecs
->ptid
= inferior_ptid
;
3605 stop_stepping (ecs
);
3608 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3609 goto process_event_stop_test
;
3611 case TARGET_WAITKIND_VFORK_DONE
:
3612 /* Done with the shared memory region. Re-insert breakpoints in
3613 the parent, and keep going. */
3616 fprintf_unfiltered (gdb_stdlog
,
3617 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3619 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3620 context_switch (ecs
->ptid
);
3622 current_inferior ()->waiting_for_vfork_done
= 0;
3623 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
3624 /* This also takes care of reinserting breakpoints in the
3625 previously locked inferior. */
3629 case TARGET_WAITKIND_EXECD
:
3631 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
3633 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3635 context_switch (ecs
->ptid
);
3636 reinit_frame_cache ();
3639 singlestep_breakpoints_inserted_p
= 0;
3640 cancel_single_step_breakpoints ();
3642 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3644 /* Do whatever is necessary to the parent branch of the vfork. */
3645 handle_vfork_child_exec_or_exit (1);
3647 /* This causes the eventpoints and symbol table to be reset.
3648 Must do this now, before trying to determine whether to
3650 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
3652 ecs
->event_thread
->control
.stop_bpstat
3653 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3654 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3656 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3658 /* Note that this may be referenced from inside
3659 bpstat_stop_status above, through inferior_has_execd. */
3660 xfree (ecs
->ws
.value
.execd_pathname
);
3661 ecs
->ws
.value
.execd_pathname
= NULL
;
3663 /* If no catchpoint triggered for this, then keep going. */
3664 if (ecs
->random_signal
)
3666 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3670 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3671 goto process_event_stop_test
;
3673 /* Be careful not to try to gather much state about a thread
3674 that's in a syscall. It's frequently a losing proposition. */
3675 case TARGET_WAITKIND_SYSCALL_ENTRY
:
3677 fprintf_unfiltered (gdb_stdlog
,
3678 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3679 /* Getting the current syscall number. */
3680 if (handle_syscall_event (ecs
) != 0)
3682 goto process_event_stop_test
;
3684 /* Before examining the threads further, step this thread to
3685 get it entirely out of the syscall. (We get notice of the
3686 event when the thread is just on the verge of exiting a
3687 syscall. Stepping one instruction seems to get it back
3689 case TARGET_WAITKIND_SYSCALL_RETURN
:
3691 fprintf_unfiltered (gdb_stdlog
,
3692 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3693 if (handle_syscall_event (ecs
) != 0)
3695 goto process_event_stop_test
;
3697 case TARGET_WAITKIND_STOPPED
:
3699 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
3700 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
3703 case TARGET_WAITKIND_NO_HISTORY
:
3705 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
3706 /* Reverse execution: target ran out of history info. */
3707 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3708 print_no_history_reason ();
3709 stop_stepping (ecs
);
3713 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
3715 /* Do we need to clean up the state of a thread that has
3716 completed a displaced single-step? (Doing so usually affects
3717 the PC, so do it here, before we set stop_pc.) */
3718 displaced_step_fixup (ecs
->ptid
,
3719 ecs
->event_thread
->suspend
.stop_signal
);
3721 /* If we either finished a single-step or hit a breakpoint, but
3722 the user wanted this thread to be stopped, pretend we got a
3723 SIG0 (generic unsignaled stop). */
3725 if (ecs
->event_thread
->stop_requested
3726 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3727 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3730 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3734 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3735 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3736 struct cleanup
*old_chain
= save_inferior_ptid ();
3738 inferior_ptid
= ecs
->ptid
;
3740 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
3741 paddress (gdbarch
, stop_pc
));
3742 if (target_stopped_by_watchpoint ())
3746 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
3748 if (target_stopped_data_address (¤t_target
, &addr
))
3749 fprintf_unfiltered (gdb_stdlog
,
3750 "infrun: stopped data address = %s\n",
3751 paddress (gdbarch
, addr
));
3753 fprintf_unfiltered (gdb_stdlog
,
3754 "infrun: (no data address available)\n");
3757 do_cleanups (old_chain
);
3760 if (stepping_past_singlestep_breakpoint
)
3762 gdb_assert (singlestep_breakpoints_inserted_p
);
3763 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
3764 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
3766 stepping_past_singlestep_breakpoint
= 0;
3768 /* We've either finished single-stepping past the single-step
3769 breakpoint, or stopped for some other reason. It would be nice if
3770 we could tell, but we can't reliably. */
3771 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3774 fprintf_unfiltered (gdb_stdlog
,
3775 "infrun: stepping_past_"
3776 "singlestep_breakpoint\n");
3777 /* Pull the single step breakpoints out of the target. */
3778 remove_single_step_breakpoints ();
3779 singlestep_breakpoints_inserted_p
= 0;
3781 ecs
->random_signal
= 0;
3782 ecs
->event_thread
->control
.trap_expected
= 0;
3784 context_switch (saved_singlestep_ptid
);
3785 if (deprecated_context_hook
)
3786 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3788 resume (1, GDB_SIGNAL_0
);
3789 prepare_to_wait (ecs
);
3794 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
3796 /* In non-stop mode, there's never a deferred_step_ptid set. */
3797 gdb_assert (!non_stop
);
3799 /* If we stopped for some other reason than single-stepping, ignore
3800 the fact that we were supposed to switch back. */
3801 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3804 fprintf_unfiltered (gdb_stdlog
,
3805 "infrun: handling deferred step\n");
3807 /* Pull the single step breakpoints out of the target. */
3808 if (singlestep_breakpoints_inserted_p
)
3810 remove_single_step_breakpoints ();
3811 singlestep_breakpoints_inserted_p
= 0;
3814 ecs
->event_thread
->control
.trap_expected
= 0;
3816 /* Note: We do not call context_switch at this point, as the
3817 context is already set up for stepping the original thread. */
3818 switch_to_thread (deferred_step_ptid
);
3819 deferred_step_ptid
= null_ptid
;
3820 /* Suppress spurious "Switching to ..." message. */
3821 previous_inferior_ptid
= inferior_ptid
;
3823 resume (1, GDB_SIGNAL_0
);
3824 prepare_to_wait (ecs
);
3828 deferred_step_ptid
= null_ptid
;
3831 /* See if a thread hit a thread-specific breakpoint that was meant for
3832 another thread. If so, then step that thread past the breakpoint,
3835 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3837 int thread_hop_needed
= 0;
3838 struct address_space
*aspace
=
3839 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
3841 /* Check if a regular breakpoint has been hit before checking
3842 for a potential single step breakpoint. Otherwise, GDB will
3843 not see this breakpoint hit when stepping onto breakpoints. */
3844 if (regular_breakpoint_inserted_here_p (aspace
, stop_pc
))
3846 ecs
->random_signal
= 0;
3847 if (!breakpoint_thread_match (aspace
, stop_pc
, ecs
->ptid
))
3848 thread_hop_needed
= 1;
3850 else if (singlestep_breakpoints_inserted_p
)
3852 /* We have not context switched yet, so this should be true
3853 no matter which thread hit the singlestep breakpoint. */
3854 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
3856 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
3858 target_pid_to_str (ecs
->ptid
));
3860 ecs
->random_signal
= 0;
3861 /* The call to in_thread_list is necessary because PTIDs sometimes
3862 change when we go from single-threaded to multi-threaded. If
3863 the singlestep_ptid is still in the list, assume that it is
3864 really different from ecs->ptid. */
3865 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
3866 && in_thread_list (singlestep_ptid
))
3868 /* If the PC of the thread we were trying to single-step
3869 has changed, discard this event (which we were going
3870 to ignore anyway), and pretend we saw that thread
3871 trap. This prevents us continuously moving the
3872 single-step breakpoint forward, one instruction at a
3873 time. If the PC has changed, then the thread we were
3874 trying to single-step has trapped or been signalled,
3875 but the event has not been reported to GDB yet.
3877 There might be some cases where this loses signal
3878 information, if a signal has arrived at exactly the
3879 same time that the PC changed, but this is the best
3880 we can do with the information available. Perhaps we
3881 should arrange to report all events for all threads
3882 when they stop, or to re-poll the remote looking for
3883 this particular thread (i.e. temporarily enable
3886 CORE_ADDR new_singlestep_pc
3887 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
3889 if (new_singlestep_pc
!= singlestep_pc
)
3891 enum gdb_signal stop_signal
;
3894 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
3895 " but expected thread advanced also\n");
3897 /* The current context still belongs to
3898 singlestep_ptid. Don't swap here, since that's
3899 the context we want to use. Just fudge our
3900 state and continue. */
3901 stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
3902 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3903 ecs
->ptid
= singlestep_ptid
;
3904 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3905 ecs
->event_thread
->suspend
.stop_signal
= stop_signal
;
3906 stop_pc
= new_singlestep_pc
;
3911 fprintf_unfiltered (gdb_stdlog
,
3912 "infrun: unexpected thread\n");
3914 thread_hop_needed
= 1;
3915 stepping_past_singlestep_breakpoint
= 1;
3916 saved_singlestep_ptid
= singlestep_ptid
;
3921 if (thread_hop_needed
)
3923 struct regcache
*thread_regcache
;
3924 int remove_status
= 0;
3927 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
3929 /* Switch context before touching inferior memory, the
3930 previous thread may have exited. */
3931 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
3932 context_switch (ecs
->ptid
);
3934 /* Saw a breakpoint, but it was hit by the wrong thread.
3937 if (singlestep_breakpoints_inserted_p
)
3939 /* Pull the single step breakpoints out of the target. */
3940 remove_single_step_breakpoints ();
3941 singlestep_breakpoints_inserted_p
= 0;
3944 /* If the arch can displace step, don't remove the
3946 thread_regcache
= get_thread_regcache (ecs
->ptid
);
3947 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
3948 remove_status
= remove_breakpoints ();
3950 /* Did we fail to remove breakpoints? If so, try
3951 to set the PC past the bp. (There's at least
3952 one situation in which we can fail to remove
3953 the bp's: On HP-UX's that use ttrace, we can't
3954 change the address space of a vforking child
3955 process until the child exits (well, okay, not
3956 then either :-) or execs. */
3957 if (remove_status
!= 0)
3958 error (_("Cannot step over breakpoint hit in wrong thread"));
3963 /* Only need to require the next event from this
3964 thread in all-stop mode. */
3965 waiton_ptid
= ecs
->ptid
;
3966 infwait_state
= infwait_thread_hop_state
;
3969 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3974 else if (singlestep_breakpoints_inserted_p
)
3976 ecs
->random_signal
= 0;
3980 ecs
->random_signal
= 1;
3982 /* See if something interesting happened to the non-current thread. If
3983 so, then switch to that thread. */
3984 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3987 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
3989 context_switch (ecs
->ptid
);
3991 if (deprecated_context_hook
)
3992 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3995 /* At this point, get hold of the now-current thread's frame. */
3996 frame
= get_current_frame ();
3997 gdbarch
= get_frame_arch (frame
);
3999 if (singlestep_breakpoints_inserted_p
)
4001 /* Pull the single step breakpoints out of the target. */
4002 remove_single_step_breakpoints ();
4003 singlestep_breakpoints_inserted_p
= 0;
4006 if (stepped_after_stopped_by_watchpoint
)
4007 stopped_by_watchpoint
= 0;
4009 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
4011 /* If necessary, step over this watchpoint. We'll be back to display
4013 if (stopped_by_watchpoint
4014 && (target_have_steppable_watchpoint
4015 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
4017 /* At this point, we are stopped at an instruction which has
4018 attempted to write to a piece of memory under control of
4019 a watchpoint. The instruction hasn't actually executed
4020 yet. If we were to evaluate the watchpoint expression
4021 now, we would get the old value, and therefore no change
4022 would seem to have occurred.
4024 In order to make watchpoints work `right', we really need
4025 to complete the memory write, and then evaluate the
4026 watchpoint expression. We do this by single-stepping the
4029 It may not be necessary to disable the watchpoint to stop over
4030 it. For example, the PA can (with some kernel cooperation)
4031 single step over a watchpoint without disabling the watchpoint.
4033 It is far more common to need to disable a watchpoint to step
4034 the inferior over it. If we have non-steppable watchpoints,
4035 we must disable the current watchpoint; it's simplest to
4036 disable all watchpoints and breakpoints. */
4039 if (!target_have_steppable_watchpoint
)
4041 remove_breakpoints ();
4042 /* See comment in resume why we need to stop bypassing signals
4043 while breakpoints have been removed. */
4044 target_pass_signals (0, NULL
);
4047 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
4048 target_resume (ecs
->ptid
, hw_step
, GDB_SIGNAL_0
);
4049 waiton_ptid
= ecs
->ptid
;
4050 if (target_have_steppable_watchpoint
)
4051 infwait_state
= infwait_step_watch_state
;
4053 infwait_state
= infwait_nonstep_watch_state
;
4054 prepare_to_wait (ecs
);
4058 clear_stop_func (ecs
);
4059 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4060 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4061 ecs
->event_thread
->control
.stop_step
= 0;
4062 stop_print_frame
= 1;
4063 ecs
->random_signal
= 0;
4064 stopped_by_random_signal
= 0;
4066 /* Hide inlined functions starting here, unless we just performed stepi or
4067 nexti. After stepi and nexti, always show the innermost frame (not any
4068 inline function call sites). */
4069 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4071 struct address_space
*aspace
=
4072 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4074 /* skip_inline_frames is expensive, so we avoid it if we can
4075 determine that the address is one where functions cannot have
4076 been inlined. This improves performance with inferiors that
4077 load a lot of shared libraries, because the solib event
4078 breakpoint is defined as the address of a function (i.e. not
4079 inline). Note that we have to check the previous PC as well
4080 as the current one to catch cases when we have just
4081 single-stepped off a breakpoint prior to reinstating it.
4082 Note that we're assuming that the code we single-step to is
4083 not inline, but that's not definitive: there's nothing
4084 preventing the event breakpoint function from containing
4085 inlined code, and the single-step ending up there. If the
4086 user had set a breakpoint on that inlined code, the missing
4087 skip_inline_frames call would break things. Fortunately
4088 that's an extremely unlikely scenario. */
4089 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4090 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4091 && ecs
->event_thread
->control
.trap_expected
4092 && pc_at_non_inline_function (aspace
,
4093 ecs
->event_thread
->prev_pc
,
4095 skip_inline_frames (ecs
->ptid
);
4098 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4099 && ecs
->event_thread
->control
.trap_expected
4100 && gdbarch_single_step_through_delay_p (gdbarch
)
4101 && currently_stepping (ecs
->event_thread
))
4103 /* We're trying to step off a breakpoint. Turns out that we're
4104 also on an instruction that needs to be stepped multiple
4105 times before it's been fully executing. E.g., architectures
4106 with a delay slot. It needs to be stepped twice, once for
4107 the instruction and once for the delay slot. */
4108 int step_through_delay
4109 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4111 if (debug_infrun
&& step_through_delay
)
4112 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4113 if (ecs
->event_thread
->control
.step_range_end
== 0
4114 && step_through_delay
)
4116 /* The user issued a continue when stopped at a breakpoint.
4117 Set up for another trap and get out of here. */
4118 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4122 else if (step_through_delay
)
4124 /* The user issued a step when stopped at a breakpoint.
4125 Maybe we should stop, maybe we should not - the delay
4126 slot *might* correspond to a line of source. In any
4127 case, don't decide that here, just set
4128 ecs->stepping_over_breakpoint, making sure we
4129 single-step again before breakpoints are re-inserted. */
4130 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4134 /* Look at the cause of the stop, and decide what to do.
4135 The alternatives are:
4136 1) stop_stepping and return; to really stop and return to the debugger,
4137 2) keep_going and return to start up again
4138 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
4139 3) set ecs->random_signal to 1, and the decision between 1 and 2
4140 will be made according to the signal handling tables. */
4142 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4143 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4144 || stop_soon
== STOP_QUIETLY_REMOTE
)
4146 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4150 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4151 stop_print_frame
= 0;
4152 stop_stepping (ecs
);
4156 /* This is originated from start_remote(), start_inferior() and
4157 shared libraries hook functions. */
4158 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4161 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4162 stop_stepping (ecs
);
4166 /* This originates from attach_command(). We need to overwrite
4167 the stop_signal here, because some kernels don't ignore a
4168 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4169 See more comments in inferior.h. On the other hand, if we
4170 get a non-SIGSTOP, report it to the user - assume the backend
4171 will handle the SIGSTOP if it should show up later.
4173 Also consider that the attach is complete when we see a
4174 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4175 target extended-remote report it instead of a SIGSTOP
4176 (e.g. gdbserver). We already rely on SIGTRAP being our
4177 signal, so this is no exception.
4179 Also consider that the attach is complete when we see a
4180 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4181 the target to stop all threads of the inferior, in case the
4182 low level attach operation doesn't stop them implicitly. If
4183 they weren't stopped implicitly, then the stub will report a
4184 GDB_SIGNAL_0, meaning: stopped for no particular reason
4185 other than GDB's request. */
4186 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4187 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
4188 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4189 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
4191 stop_stepping (ecs
);
4192 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4196 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4197 handles this event. */
4198 ecs
->event_thread
->control
.stop_bpstat
4199 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4200 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4202 /* Following in case break condition called a
4204 stop_print_frame
= 1;
4206 /* This is where we handle "moribund" watchpoints. Unlike
4207 software breakpoints traps, hardware watchpoint traps are
4208 always distinguishable from random traps. If no high-level
4209 watchpoint is associated with the reported stop data address
4210 anymore, then the bpstat does not explain the signal ---
4211 simply make sure to ignore it if `stopped_by_watchpoint' is
4215 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4216 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4217 && stopped_by_watchpoint
)
4218 fprintf_unfiltered (gdb_stdlog
,
4219 "infrun: no user watchpoint explains "
4220 "watchpoint SIGTRAP, ignoring\n");
4222 /* NOTE: cagney/2003-03-29: These two checks for a random signal
4223 at one stage in the past included checks for an inferior
4224 function call's call dummy's return breakpoint. The original
4225 comment, that went with the test, read:
4227 ``End of a stack dummy. Some systems (e.g. Sony news) give
4228 another signal besides SIGTRAP, so check here as well as
4231 If someone ever tries to get call dummys on a
4232 non-executable stack to work (where the target would stop
4233 with something like a SIGSEGV), then those tests might need
4234 to be re-instated. Given, however, that the tests were only
4235 enabled when momentary breakpoints were not being used, I
4236 suspect that it won't be the case.
4238 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4239 be necessary for call dummies on a non-executable stack on
4242 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4244 = !(bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4245 || stopped_by_watchpoint
4246 || ecs
->event_thread
->control
.trap_expected
4247 || (ecs
->event_thread
->control
.step_range_end
4248 && (ecs
->event_thread
->control
.step_resume_breakpoint
4252 ecs
->random_signal
= !bpstat_explains_signal
4253 (ecs
->event_thread
->control
.stop_bpstat
);
4254 if (!ecs
->random_signal
)
4255 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
4259 /* When we reach this point, we've pretty much decided
4260 that the reason for stopping must've been a random
4261 (unexpected) signal. */
4264 ecs
->random_signal
= 1;
4266 process_event_stop_test
:
4268 /* Re-fetch current thread's frame in case we did a
4269 "goto process_event_stop_test" above. */
4270 frame
= get_current_frame ();
4271 gdbarch
= get_frame_arch (frame
);
4273 /* For the program's own signals, act according to
4274 the signal handling tables. */
4276 if (ecs
->random_signal
)
4278 /* Signal not for debugging purposes. */
4280 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
4283 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
4284 ecs
->event_thread
->suspend
.stop_signal
);
4286 stopped_by_random_signal
= 1;
4288 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4291 target_terminal_ours_for_output ();
4292 print_signal_received_reason
4293 (ecs
->event_thread
->suspend
.stop_signal
);
4295 /* Always stop on signals if we're either just gaining control
4296 of the program, or the user explicitly requested this thread
4297 to remain stopped. */
4298 if (stop_soon
!= NO_STOP_QUIETLY
4299 || ecs
->event_thread
->stop_requested
4301 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4303 stop_stepping (ecs
);
4306 /* If not going to stop, give terminal back
4307 if we took it away. */
4309 target_terminal_inferior ();
4311 /* Clear the signal if it should not be passed. */
4312 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4313 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4315 if (ecs
->event_thread
->prev_pc
== stop_pc
4316 && ecs
->event_thread
->control
.trap_expected
4317 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4319 /* We were just starting a new sequence, attempting to
4320 single-step off of a breakpoint and expecting a SIGTRAP.
4321 Instead this signal arrives. This signal will take us out
4322 of the stepping range so GDB needs to remember to, when
4323 the signal handler returns, resume stepping off that
4325 /* To simplify things, "continue" is forced to use the same
4326 code paths as single-step - set a breakpoint at the
4327 signal return address and then, once hit, step off that
4330 fprintf_unfiltered (gdb_stdlog
,
4331 "infrun: signal arrived while stepping over "
4334 insert_hp_step_resume_breakpoint_at_frame (frame
);
4335 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4336 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4337 ecs
->event_thread
->control
.trap_expected
= 0;
4342 if (ecs
->event_thread
->control
.step_range_end
!= 0
4343 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4344 && (ecs
->event_thread
->control
.step_range_start
<= stop_pc
4345 && stop_pc
< ecs
->event_thread
->control
.step_range_end
)
4346 && frame_id_eq (get_stack_frame_id (frame
),
4347 ecs
->event_thread
->control
.step_stack_frame_id
)
4348 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4350 /* The inferior is about to take a signal that will take it
4351 out of the single step range. Set a breakpoint at the
4352 current PC (which is presumably where the signal handler
4353 will eventually return) and then allow the inferior to
4356 Note that this is only needed for a signal delivered
4357 while in the single-step range. Nested signals aren't a
4358 problem as they eventually all return. */
4360 fprintf_unfiltered (gdb_stdlog
,
4361 "infrun: signal may take us out of "
4362 "single-step range\n");
4364 insert_hp_step_resume_breakpoint_at_frame (frame
);
4365 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4366 ecs
->event_thread
->control
.trap_expected
= 0;
4371 /* Note: step_resume_breakpoint may be non-NULL. This occures
4372 when either there's a nested signal, or when there's a
4373 pending signal enabled just as the signal handler returns
4374 (leaving the inferior at the step-resume-breakpoint without
4375 actually executing it). Either way continue until the
4376 breakpoint is really hit. */
4381 /* Handle cases caused by hitting a breakpoint. */
4383 CORE_ADDR jmp_buf_pc
;
4384 struct bpstat_what what
;
4386 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4388 if (what
.call_dummy
)
4390 stop_stack_dummy
= what
.call_dummy
;
4393 /* If we hit an internal event that triggers symbol changes, the
4394 current frame will be invalidated within bpstat_what (e.g., if
4395 we hit an internal solib event). Re-fetch it. */
4396 frame
= get_current_frame ();
4397 gdbarch
= get_frame_arch (frame
);
4399 switch (what
.main_action
)
4401 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4402 /* If we hit the breakpoint at longjmp while stepping, we
4403 install a momentary breakpoint at the target of the
4407 fprintf_unfiltered (gdb_stdlog
,
4408 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4410 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4412 if (what
.is_longjmp
)
4414 struct value
*arg_value
;
4416 /* If we set the longjmp breakpoint via a SystemTap probe,
4417 then use it to extract the arguments. The destination
4418 PC is the third argument to the probe. */
4419 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4421 jmp_buf_pc
= value_as_address (arg_value
);
4422 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4423 || !gdbarch_get_longjmp_target (gdbarch
,
4424 frame
, &jmp_buf_pc
))
4427 fprintf_unfiltered (gdb_stdlog
,
4428 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4429 "(!gdbarch_get_longjmp_target)\n");
4434 /* We're going to replace the current step-resume breakpoint
4435 with a longjmp-resume breakpoint. */
4436 delete_step_resume_breakpoint (ecs
->event_thread
);
4438 /* Insert a breakpoint at resume address. */
4439 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4442 check_exception_resume (ecs
, frame
);
4446 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4448 fprintf_unfiltered (gdb_stdlog
,
4449 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4451 if (what
.is_longjmp
)
4453 gdb_assert (ecs
->event_thread
->control
.step_resume_breakpoint
4455 delete_step_resume_breakpoint (ecs
->event_thread
);
4459 /* There are several cases to consider.
4461 1. The initiating frame no longer exists. In this case
4462 we must stop, because the exception has gone too far.
4464 2. The initiating frame exists, and is the same as the
4465 current frame. We stop, because the exception has been
4468 3. The initiating frame exists and is different from
4469 the current frame. This means the exception has been
4470 caught beneath the initiating frame, so keep going. */
4471 struct frame_info
*init_frame
4472 = frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4474 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4476 delete_exception_resume_breakpoint (ecs
->event_thread
);
4480 struct frame_id current_id
4481 = get_frame_id (get_current_frame ());
4482 if (frame_id_eq (current_id
,
4483 ecs
->event_thread
->initiating_frame
))
4485 /* Case 2. Fall through. */
4495 /* For Cases 1 and 2, remove the step-resume breakpoint,
4497 delete_step_resume_breakpoint (ecs
->event_thread
);
4500 ecs
->event_thread
->control
.stop_step
= 1;
4501 print_end_stepping_range_reason ();
4502 stop_stepping (ecs
);
4505 case BPSTAT_WHAT_SINGLE
:
4507 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4508 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4509 /* Still need to check other stuff, at least the case
4510 where we are stepping and step out of the right range. */
4513 case BPSTAT_WHAT_STEP_RESUME
:
4515 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4517 delete_step_resume_breakpoint (ecs
->event_thread
);
4518 if (ecs
->event_thread
->control
.proceed_to_finish
4519 && execution_direction
== EXEC_REVERSE
)
4521 struct thread_info
*tp
= ecs
->event_thread
;
4523 /* We are finishing a function in reverse, and just hit
4524 the step-resume breakpoint at the start address of the
4525 function, and we're almost there -- just need to back
4526 up by one more single-step, which should take us back
4527 to the function call. */
4528 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4532 fill_in_stop_func (gdbarch
, ecs
);
4533 if (stop_pc
== ecs
->stop_func_start
4534 && execution_direction
== EXEC_REVERSE
)
4536 /* We are stepping over a function call in reverse, and
4537 just hit the step-resume breakpoint at the start
4538 address of the function. Go back to single-stepping,
4539 which should take us back to the function call. */
4540 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4546 case BPSTAT_WHAT_STOP_NOISY
:
4548 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4549 stop_print_frame
= 1;
4551 /* We are about to nuke the step_resume_breakpointt via the
4552 cleanup chain, so no need to worry about it here. */
4554 stop_stepping (ecs
);
4557 case BPSTAT_WHAT_STOP_SILENT
:
4559 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4560 stop_print_frame
= 0;
4562 /* We are about to nuke the step_resume_breakpoin via the
4563 cleanup chain, so no need to worry about it here. */
4565 stop_stepping (ecs
);
4568 case BPSTAT_WHAT_HP_STEP_RESUME
:
4570 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4572 delete_step_resume_breakpoint (ecs
->event_thread
);
4573 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4575 /* Back when the step-resume breakpoint was inserted, we
4576 were trying to single-step off a breakpoint. Go back
4578 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4579 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4585 case BPSTAT_WHAT_KEEP_CHECKING
:
4590 /* We come here if we hit a breakpoint but should not
4591 stop for it. Possibly we also were stepping
4592 and should stop for that. So fall through and
4593 test for stepping. But, if not stepping,
4596 /* In all-stop mode, if we're currently stepping but have stopped in
4597 some other thread, we need to switch back to the stepped thread. */
4600 struct thread_info
*tp
;
4602 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
4606 /* However, if the current thread is blocked on some internal
4607 breakpoint, and we simply need to step over that breakpoint
4608 to get it going again, do that first. */
4609 if ((ecs
->event_thread
->control
.trap_expected
4610 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
4611 || ecs
->event_thread
->stepping_over_breakpoint
)
4617 /* If the stepping thread exited, then don't try to switch
4618 back and resume it, which could fail in several different
4619 ways depending on the target. Instead, just keep going.
4621 We can find a stepping dead thread in the thread list in
4624 - The target supports thread exit events, and when the
4625 target tries to delete the thread from the thread list,
4626 inferior_ptid pointed at the exiting thread. In such
4627 case, calling delete_thread does not really remove the
4628 thread from the list; instead, the thread is left listed,
4629 with 'exited' state.
4631 - The target's debug interface does not support thread
4632 exit events, and so we have no idea whatsoever if the
4633 previously stepping thread is still alive. For that
4634 reason, we need to synchronously query the target
4636 if (is_exited (tp
->ptid
)
4637 || !target_thread_alive (tp
->ptid
))
4640 fprintf_unfiltered (gdb_stdlog
,
4641 "infrun: not switching back to "
4642 "stepped thread, it has vanished\n");
4644 delete_thread (tp
->ptid
);
4649 /* Otherwise, we no longer expect a trap in the current thread.
4650 Clear the trap_expected flag before switching back -- this is
4651 what keep_going would do as well, if we called it. */
4652 ecs
->event_thread
->control
.trap_expected
= 0;
4655 fprintf_unfiltered (gdb_stdlog
,
4656 "infrun: switching back to stepped thread\n");
4658 ecs
->event_thread
= tp
;
4659 ecs
->ptid
= tp
->ptid
;
4660 context_switch (ecs
->ptid
);
4666 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4669 fprintf_unfiltered (gdb_stdlog
,
4670 "infrun: step-resume breakpoint is inserted\n");
4672 /* Having a step-resume breakpoint overrides anything
4673 else having to do with stepping commands until
4674 that breakpoint is reached. */
4679 if (ecs
->event_thread
->control
.step_range_end
== 0)
4682 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4683 /* Likewise if we aren't even stepping. */
4688 /* Re-fetch current thread's frame in case the code above caused
4689 the frame cache to be re-initialized, making our FRAME variable
4690 a dangling pointer. */
4691 frame
= get_current_frame ();
4692 gdbarch
= get_frame_arch (frame
);
4693 fill_in_stop_func (gdbarch
, ecs
);
4695 /* If stepping through a line, keep going if still within it.
4697 Note that step_range_end is the address of the first instruction
4698 beyond the step range, and NOT the address of the last instruction
4701 Note also that during reverse execution, we may be stepping
4702 through a function epilogue and therefore must detect when
4703 the current-frame changes in the middle of a line. */
4705 if (stop_pc
>= ecs
->event_thread
->control
.step_range_start
4706 && stop_pc
< ecs
->event_thread
->control
.step_range_end
4707 && (execution_direction
!= EXEC_REVERSE
4708 || frame_id_eq (get_frame_id (frame
),
4709 ecs
->event_thread
->control
.step_frame_id
)))
4713 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4714 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4715 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4717 /* When stepping backward, stop at beginning of line range
4718 (unless it's the function entry point, in which case
4719 keep going back to the call point). */
4720 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4721 && stop_pc
!= ecs
->stop_func_start
4722 && execution_direction
== EXEC_REVERSE
)
4724 ecs
->event_thread
->control
.stop_step
= 1;
4725 print_end_stepping_range_reason ();
4726 stop_stepping (ecs
);
4734 /* We stepped out of the stepping range. */
4736 /* If we are stepping at the source level and entered the runtime
4737 loader dynamic symbol resolution code...
4739 EXEC_FORWARD: we keep on single stepping until we exit the run
4740 time loader code and reach the callee's address.
4742 EXEC_REVERSE: we've already executed the callee (backward), and
4743 the runtime loader code is handled just like any other
4744 undebuggable function call. Now we need only keep stepping
4745 backward through the trampoline code, and that's handled further
4746 down, so there is nothing for us to do here. */
4748 if (execution_direction
!= EXEC_REVERSE
4749 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4750 && in_solib_dynsym_resolve_code (stop_pc
))
4752 CORE_ADDR pc_after_resolver
=
4753 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
4756 fprintf_unfiltered (gdb_stdlog
,
4757 "infrun: stepped into dynsym resolve code\n");
4759 if (pc_after_resolver
)
4761 /* Set up a step-resume breakpoint at the address
4762 indicated by SKIP_SOLIB_RESOLVER. */
4763 struct symtab_and_line sr_sal
;
4766 sr_sal
.pc
= pc_after_resolver
;
4767 sr_sal
.pspace
= get_frame_program_space (frame
);
4769 insert_step_resume_breakpoint_at_sal (gdbarch
,
4770 sr_sal
, null_frame_id
);
4777 if (ecs
->event_thread
->control
.step_range_end
!= 1
4778 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4779 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4780 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
4783 fprintf_unfiltered (gdb_stdlog
,
4784 "infrun: stepped into signal trampoline\n");
4785 /* The inferior, while doing a "step" or "next", has ended up in
4786 a signal trampoline (either by a signal being delivered or by
4787 the signal handler returning). Just single-step until the
4788 inferior leaves the trampoline (either by calling the handler
4794 /* If we're in the return path from a shared library trampoline,
4795 we want to proceed through the trampoline when stepping. */
4796 /* macro/2012-04-25: This needs to come before the subroutine
4797 call check below as on some targets return trampolines look
4798 like subroutine calls (MIPS16 return thunks). */
4799 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4800 stop_pc
, ecs
->stop_func_name
)
4801 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
4803 /* Determine where this trampoline returns. */
4804 CORE_ADDR real_stop_pc
;
4806 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4809 fprintf_unfiltered (gdb_stdlog
,
4810 "infrun: stepped into solib return tramp\n");
4812 /* Only proceed through if we know where it's going. */
4815 /* And put the step-breakpoint there and go until there. */
4816 struct symtab_and_line sr_sal
;
4818 init_sal (&sr_sal
); /* initialize to zeroes */
4819 sr_sal
.pc
= real_stop_pc
;
4820 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4821 sr_sal
.pspace
= get_frame_program_space (frame
);
4823 /* Do not specify what the fp should be when we stop since
4824 on some machines the prologue is where the new fp value
4826 insert_step_resume_breakpoint_at_sal (gdbarch
,
4827 sr_sal
, null_frame_id
);
4829 /* Restart without fiddling with the step ranges or
4836 /* Check for subroutine calls. The check for the current frame
4837 equalling the step ID is not necessary - the check of the
4838 previous frame's ID is sufficient - but it is a common case and
4839 cheaper than checking the previous frame's ID.
4841 NOTE: frame_id_eq will never report two invalid frame IDs as
4842 being equal, so to get into this block, both the current and
4843 previous frame must have valid frame IDs. */
4844 /* The outer_frame_id check is a heuristic to detect stepping
4845 through startup code. If we step over an instruction which
4846 sets the stack pointer from an invalid value to a valid value,
4847 we may detect that as a subroutine call from the mythical
4848 "outermost" function. This could be fixed by marking
4849 outermost frames as !stack_p,code_p,special_p. Then the
4850 initial outermost frame, before sp was valid, would
4851 have code_addr == &_start. See the comment in frame_id_eq
4853 if (!frame_id_eq (get_stack_frame_id (frame
),
4854 ecs
->event_thread
->control
.step_stack_frame_id
)
4855 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4856 ecs
->event_thread
->control
.step_stack_frame_id
)
4857 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
4859 || step_start_function
!= find_pc_function (stop_pc
))))
4861 CORE_ADDR real_stop_pc
;
4864 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
4866 if ((ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
4867 || ((ecs
->event_thread
->control
.step_range_end
== 1)
4868 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
4869 ecs
->stop_func_start
)))
4871 /* I presume that step_over_calls is only 0 when we're
4872 supposed to be stepping at the assembly language level
4873 ("stepi"). Just stop. */
4874 /* Also, maybe we just did a "nexti" inside a prolog, so we
4875 thought it was a subroutine call but it was not. Stop as
4877 /* And this works the same backward as frontward. MVS */
4878 ecs
->event_thread
->control
.stop_step
= 1;
4879 print_end_stepping_range_reason ();
4880 stop_stepping (ecs
);
4884 /* Reverse stepping through solib trampolines. */
4886 if (execution_direction
== EXEC_REVERSE
4887 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
4888 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4889 || (ecs
->stop_func_start
== 0
4890 && in_solib_dynsym_resolve_code (stop_pc
))))
4892 /* Any solib trampoline code can be handled in reverse
4893 by simply continuing to single-step. We have already
4894 executed the solib function (backwards), and a few
4895 steps will take us back through the trampoline to the
4901 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4903 /* We're doing a "next".
4905 Normal (forward) execution: set a breakpoint at the
4906 callee's return address (the address at which the caller
4909 Reverse (backward) execution. set the step-resume
4910 breakpoint at the start of the function that we just
4911 stepped into (backwards), and continue to there. When we
4912 get there, we'll need to single-step back to the caller. */
4914 if (execution_direction
== EXEC_REVERSE
)
4916 struct symtab_and_line sr_sal
;
4918 /* Normal function call return (static or dynamic). */
4920 sr_sal
.pc
= ecs
->stop_func_start
;
4921 sr_sal
.pspace
= get_frame_program_space (frame
);
4922 insert_step_resume_breakpoint_at_sal (gdbarch
,
4923 sr_sal
, null_frame_id
);
4926 insert_step_resume_breakpoint_at_caller (frame
);
4932 /* If we are in a function call trampoline (a stub between the
4933 calling routine and the real function), locate the real
4934 function. That's what tells us (a) whether we want to step
4935 into it at all, and (b) what prologue we want to run to the
4936 end of, if we do step into it. */
4937 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
4938 if (real_stop_pc
== 0)
4939 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4940 if (real_stop_pc
!= 0)
4941 ecs
->stop_func_start
= real_stop_pc
;
4943 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
4945 struct symtab_and_line sr_sal
;
4948 sr_sal
.pc
= ecs
->stop_func_start
;
4949 sr_sal
.pspace
= get_frame_program_space (frame
);
4951 insert_step_resume_breakpoint_at_sal (gdbarch
,
4952 sr_sal
, null_frame_id
);
4957 /* If we have line number information for the function we are
4958 thinking of stepping into and the function isn't on the skip
4961 If there are several symtabs at that PC (e.g. with include
4962 files), just want to know whether *any* of them have line
4963 numbers. find_pc_line handles this. */
4965 struct symtab_and_line tmp_sal
;
4967 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4968 if (tmp_sal
.line
!= 0
4969 && !function_pc_is_marked_for_skip (ecs
->stop_func_start
))
4971 if (execution_direction
== EXEC_REVERSE
)
4972 handle_step_into_function_backward (gdbarch
, ecs
);
4974 handle_step_into_function (gdbarch
, ecs
);
4979 /* If we have no line number and the step-stop-if-no-debug is
4980 set, we stop the step so that the user has a chance to switch
4981 in assembly mode. */
4982 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4983 && step_stop_if_no_debug
)
4985 ecs
->event_thread
->control
.stop_step
= 1;
4986 print_end_stepping_range_reason ();
4987 stop_stepping (ecs
);
4991 if (execution_direction
== EXEC_REVERSE
)
4993 /* Set a breakpoint at callee's start address.
4994 From there we can step once and be back in the caller. */
4995 struct symtab_and_line sr_sal
;
4998 sr_sal
.pc
= ecs
->stop_func_start
;
4999 sr_sal
.pspace
= get_frame_program_space (frame
);
5000 insert_step_resume_breakpoint_at_sal (gdbarch
,
5001 sr_sal
, null_frame_id
);
5004 /* Set a breakpoint at callee's return address (the address
5005 at which the caller will resume). */
5006 insert_step_resume_breakpoint_at_caller (frame
);
5012 /* Reverse stepping through solib trampolines. */
5014 if (execution_direction
== EXEC_REVERSE
5015 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5017 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5018 || (ecs
->stop_func_start
== 0
5019 && in_solib_dynsym_resolve_code (stop_pc
)))
5021 /* Any solib trampoline code can be handled in reverse
5022 by simply continuing to single-step. We have already
5023 executed the solib function (backwards), and a few
5024 steps will take us back through the trampoline to the
5029 else if (in_solib_dynsym_resolve_code (stop_pc
))
5031 /* Stepped backward into the solib dynsym resolver.
5032 Set a breakpoint at its start and continue, then
5033 one more step will take us out. */
5034 struct symtab_and_line sr_sal
;
5037 sr_sal
.pc
= ecs
->stop_func_start
;
5038 sr_sal
.pspace
= get_frame_program_space (frame
);
5039 insert_step_resume_breakpoint_at_sal (gdbarch
,
5040 sr_sal
, null_frame_id
);
5046 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5048 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5049 the trampoline processing logic, however, there are some trampolines
5050 that have no names, so we should do trampoline handling first. */
5051 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5052 && ecs
->stop_func_name
== NULL
5053 && stop_pc_sal
.line
== 0)
5056 fprintf_unfiltered (gdb_stdlog
,
5057 "infrun: stepped into undebuggable function\n");
5059 /* The inferior just stepped into, or returned to, an
5060 undebuggable function (where there is no debugging information
5061 and no line number corresponding to the address where the
5062 inferior stopped). Since we want to skip this kind of code,
5063 we keep going until the inferior returns from this
5064 function - unless the user has asked us not to (via
5065 set step-mode) or we no longer know how to get back
5066 to the call site. */
5067 if (step_stop_if_no_debug
5068 || !frame_id_p (frame_unwind_caller_id (frame
)))
5070 /* If we have no line number and the step-stop-if-no-debug
5071 is set, we stop the step so that the user has a chance to
5072 switch in assembly mode. */
5073 ecs
->event_thread
->control
.stop_step
= 1;
5074 print_end_stepping_range_reason ();
5075 stop_stepping (ecs
);
5080 /* Set a breakpoint at callee's return address (the address
5081 at which the caller will resume). */
5082 insert_step_resume_breakpoint_at_caller (frame
);
5088 if (ecs
->event_thread
->control
.step_range_end
== 1)
5090 /* It is stepi or nexti. We always want to stop stepping after
5093 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5094 ecs
->event_thread
->control
.stop_step
= 1;
5095 print_end_stepping_range_reason ();
5096 stop_stepping (ecs
);
5100 if (stop_pc_sal
.line
== 0)
5102 /* We have no line number information. That means to stop
5103 stepping (does this always happen right after one instruction,
5104 when we do "s" in a function with no line numbers,
5105 or can this happen as a result of a return or longjmp?). */
5107 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5108 ecs
->event_thread
->control
.stop_step
= 1;
5109 print_end_stepping_range_reason ();
5110 stop_stepping (ecs
);
5114 /* Look for "calls" to inlined functions, part one. If the inline
5115 frame machinery detected some skipped call sites, we have entered
5116 a new inline function. */
5118 if (frame_id_eq (get_frame_id (get_current_frame ()),
5119 ecs
->event_thread
->control
.step_frame_id
)
5120 && inline_skipped_frames (ecs
->ptid
))
5122 struct symtab_and_line call_sal
;
5125 fprintf_unfiltered (gdb_stdlog
,
5126 "infrun: stepped into inlined function\n");
5128 find_frame_sal (get_current_frame (), &call_sal
);
5130 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5132 /* For "step", we're going to stop. But if the call site
5133 for this inlined function is on the same source line as
5134 we were previously stepping, go down into the function
5135 first. Otherwise stop at the call site. */
5137 if (call_sal
.line
== ecs
->event_thread
->current_line
5138 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5139 step_into_inline_frame (ecs
->ptid
);
5141 ecs
->event_thread
->control
.stop_step
= 1;
5142 print_end_stepping_range_reason ();
5143 stop_stepping (ecs
);
5148 /* For "next", we should stop at the call site if it is on a
5149 different source line. Otherwise continue through the
5150 inlined function. */
5151 if (call_sal
.line
== ecs
->event_thread
->current_line
5152 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5156 ecs
->event_thread
->control
.stop_step
= 1;
5157 print_end_stepping_range_reason ();
5158 stop_stepping (ecs
);
5164 /* Look for "calls" to inlined functions, part two. If we are still
5165 in the same real function we were stepping through, but we have
5166 to go further up to find the exact frame ID, we are stepping
5167 through a more inlined call beyond its call site. */
5169 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5170 && !frame_id_eq (get_frame_id (get_current_frame ()),
5171 ecs
->event_thread
->control
.step_frame_id
)
5172 && stepped_in_from (get_current_frame (),
5173 ecs
->event_thread
->control
.step_frame_id
))
5176 fprintf_unfiltered (gdb_stdlog
,
5177 "infrun: stepping through inlined function\n");
5179 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5183 ecs
->event_thread
->control
.stop_step
= 1;
5184 print_end_stepping_range_reason ();
5185 stop_stepping (ecs
);
5190 if ((stop_pc
== stop_pc_sal
.pc
)
5191 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5192 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5194 /* We are at the start of a different line. So stop. Note that
5195 we don't stop if we step into the middle of a different line.
5196 That is said to make things like for (;;) statements work
5199 fprintf_unfiltered (gdb_stdlog
,
5200 "infrun: stepped to a different line\n");
5201 ecs
->event_thread
->control
.stop_step
= 1;
5202 print_end_stepping_range_reason ();
5203 stop_stepping (ecs
);
5207 /* We aren't done stepping.
5209 Optimize by setting the stepping range to the line.
5210 (We might not be in the original line, but if we entered a
5211 new line in mid-statement, we continue stepping. This makes
5212 things like for(;;) statements work better.) */
5214 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5215 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5216 set_step_info (frame
, stop_pc_sal
);
5219 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5223 /* Is thread TP in the middle of single-stepping? */
5226 currently_stepping (struct thread_info
*tp
)
5228 return ((tp
->control
.step_range_end
5229 && tp
->control
.step_resume_breakpoint
== NULL
)
5230 || tp
->control
.trap_expected
5231 || bpstat_should_step ());
5234 /* Returns true if any thread *but* the one passed in "data" is in the
5235 middle of stepping or of handling a "next". */
5238 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
5243 return (tp
->control
.step_range_end
5244 || tp
->control
.trap_expected
);
5247 /* Inferior has stepped into a subroutine call with source code that
5248 we should not step over. Do step to the first line of code in
5252 handle_step_into_function (struct gdbarch
*gdbarch
,
5253 struct execution_control_state
*ecs
)
5256 struct symtab_and_line stop_func_sal
, sr_sal
;
5258 fill_in_stop_func (gdbarch
, ecs
);
5260 s
= find_pc_symtab (stop_pc
);
5261 if (s
&& s
->language
!= language_asm
)
5262 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5263 ecs
->stop_func_start
);
5265 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5266 /* Use the step_resume_break to step until the end of the prologue,
5267 even if that involves jumps (as it seems to on the vax under
5269 /* If the prologue ends in the middle of a source line, continue to
5270 the end of that source line (if it is still within the function).
5271 Otherwise, just go to end of prologue. */
5272 if (stop_func_sal
.end
5273 && stop_func_sal
.pc
!= ecs
->stop_func_start
5274 && stop_func_sal
.end
< ecs
->stop_func_end
)
5275 ecs
->stop_func_start
= stop_func_sal
.end
;
5277 /* Architectures which require breakpoint adjustment might not be able
5278 to place a breakpoint at the computed address. If so, the test
5279 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5280 ecs->stop_func_start to an address at which a breakpoint may be
5281 legitimately placed.
5283 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5284 made, GDB will enter an infinite loop when stepping through
5285 optimized code consisting of VLIW instructions which contain
5286 subinstructions corresponding to different source lines. On
5287 FR-V, it's not permitted to place a breakpoint on any but the
5288 first subinstruction of a VLIW instruction. When a breakpoint is
5289 set, GDB will adjust the breakpoint address to the beginning of
5290 the VLIW instruction. Thus, we need to make the corresponding
5291 adjustment here when computing the stop address. */
5293 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5295 ecs
->stop_func_start
5296 = gdbarch_adjust_breakpoint_address (gdbarch
,
5297 ecs
->stop_func_start
);
5300 if (ecs
->stop_func_start
== stop_pc
)
5302 /* We are already there: stop now. */
5303 ecs
->event_thread
->control
.stop_step
= 1;
5304 print_end_stepping_range_reason ();
5305 stop_stepping (ecs
);
5310 /* Put the step-breakpoint there and go until there. */
5311 init_sal (&sr_sal
); /* initialize to zeroes */
5312 sr_sal
.pc
= ecs
->stop_func_start
;
5313 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5314 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5316 /* Do not specify what the fp should be when we stop since on
5317 some machines the prologue is where the new fp value is
5319 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5321 /* And make sure stepping stops right away then. */
5322 ecs
->event_thread
->control
.step_range_end
5323 = ecs
->event_thread
->control
.step_range_start
;
5328 /* Inferior has stepped backward into a subroutine call with source
5329 code that we should not step over. Do step to the beginning of the
5330 last line of code in it. */
5333 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5334 struct execution_control_state
*ecs
)
5337 struct symtab_and_line stop_func_sal
;
5339 fill_in_stop_func (gdbarch
, ecs
);
5341 s
= find_pc_symtab (stop_pc
);
5342 if (s
&& s
->language
!= language_asm
)
5343 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5344 ecs
->stop_func_start
);
5346 stop_func_sal
= find_pc_line (stop_pc
, 0);
5348 /* OK, we're just going to keep stepping here. */
5349 if (stop_func_sal
.pc
== stop_pc
)
5351 /* We're there already. Just stop stepping now. */
5352 ecs
->event_thread
->control
.stop_step
= 1;
5353 print_end_stepping_range_reason ();
5354 stop_stepping (ecs
);
5358 /* Else just reset the step range and keep going.
5359 No step-resume breakpoint, they don't work for
5360 epilogues, which can have multiple entry paths. */
5361 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5362 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5368 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5369 This is used to both functions and to skip over code. */
5372 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5373 struct symtab_and_line sr_sal
,
5374 struct frame_id sr_id
,
5375 enum bptype sr_type
)
5377 /* There should never be more than one step-resume or longjmp-resume
5378 breakpoint per thread, so we should never be setting a new
5379 step_resume_breakpoint when one is already active. */
5380 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5381 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5384 fprintf_unfiltered (gdb_stdlog
,
5385 "infrun: inserting step-resume breakpoint at %s\n",
5386 paddress (gdbarch
, sr_sal
.pc
));
5388 inferior_thread ()->control
.step_resume_breakpoint
5389 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5393 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5394 struct symtab_and_line sr_sal
,
5395 struct frame_id sr_id
)
5397 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5402 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5403 This is used to skip a potential signal handler.
5405 This is called with the interrupted function's frame. The signal
5406 handler, when it returns, will resume the interrupted function at
5410 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5412 struct symtab_and_line sr_sal
;
5413 struct gdbarch
*gdbarch
;
5415 gdb_assert (return_frame
!= NULL
);
5416 init_sal (&sr_sal
); /* initialize to zeros */
5418 gdbarch
= get_frame_arch (return_frame
);
5419 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5420 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5421 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5423 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5424 get_stack_frame_id (return_frame
),
5428 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5429 is used to skip a function after stepping into it (for "next" or if
5430 the called function has no debugging information).
5432 The current function has almost always been reached by single
5433 stepping a call or return instruction. NEXT_FRAME belongs to the
5434 current function, and the breakpoint will be set at the caller's
5437 This is a separate function rather than reusing
5438 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5439 get_prev_frame, which may stop prematurely (see the implementation
5440 of frame_unwind_caller_id for an example). */
5443 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5445 struct symtab_and_line sr_sal
;
5446 struct gdbarch
*gdbarch
;
5448 /* We shouldn't have gotten here if we don't know where the call site
5450 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5452 init_sal (&sr_sal
); /* initialize to zeros */
5454 gdbarch
= frame_unwind_caller_arch (next_frame
);
5455 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5456 frame_unwind_caller_pc (next_frame
));
5457 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5458 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5460 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5461 frame_unwind_caller_id (next_frame
));
5464 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5465 new breakpoint at the target of a jmp_buf. The handling of
5466 longjmp-resume uses the same mechanisms used for handling
5467 "step-resume" breakpoints. */
5470 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5472 /* There should never be more than one step-resume or longjmp-resume
5473 breakpoint per thread, so we should never be setting a new
5474 longjmp_resume_breakpoint when one is already active. */
5475 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5478 fprintf_unfiltered (gdb_stdlog
,
5479 "infrun: inserting longjmp-resume breakpoint at %s\n",
5480 paddress (gdbarch
, pc
));
5482 inferior_thread ()->control
.step_resume_breakpoint
=
5483 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5486 /* Insert an exception resume breakpoint. TP is the thread throwing
5487 the exception. The block B is the block of the unwinder debug hook
5488 function. FRAME is the frame corresponding to the call to this
5489 function. SYM is the symbol of the function argument holding the
5490 target PC of the exception. */
5493 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5495 struct frame_info
*frame
,
5498 volatile struct gdb_exception e
;
5500 /* We want to ignore errors here. */
5501 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5503 struct symbol
*vsym
;
5504 struct value
*value
;
5506 struct breakpoint
*bp
;
5508 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5509 value
= read_var_value (vsym
, frame
);
5510 /* If the value was optimized out, revert to the old behavior. */
5511 if (! value_optimized_out (value
))
5513 handler
= value_as_address (value
);
5516 fprintf_unfiltered (gdb_stdlog
,
5517 "infrun: exception resume at %lx\n",
5518 (unsigned long) handler
);
5520 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5521 handler
, bp_exception_resume
);
5523 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5526 bp
->thread
= tp
->num
;
5527 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5532 /* A helper for check_exception_resume that sets an
5533 exception-breakpoint based on a SystemTap probe. */
5536 insert_exception_resume_from_probe (struct thread_info
*tp
,
5537 const struct probe
*probe
,
5538 struct objfile
*objfile
,
5539 struct frame_info
*frame
)
5541 struct value
*arg_value
;
5543 struct breakpoint
*bp
;
5545 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
5549 handler
= value_as_address (arg_value
);
5552 fprintf_unfiltered (gdb_stdlog
,
5553 "infrun: exception resume at %s\n",
5554 paddress (get_objfile_arch (objfile
),
5557 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5558 handler
, bp_exception_resume
);
5559 bp
->thread
= tp
->num
;
5560 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5563 /* This is called when an exception has been intercepted. Check to
5564 see whether the exception's destination is of interest, and if so,
5565 set an exception resume breakpoint there. */
5568 check_exception_resume (struct execution_control_state
*ecs
,
5569 struct frame_info
*frame
)
5571 volatile struct gdb_exception e
;
5572 struct objfile
*objfile
;
5573 const struct probe
*probe
;
5574 struct symbol
*func
;
5576 /* First see if this exception unwinding breakpoint was set via a
5577 SystemTap probe point. If so, the probe has two arguments: the
5578 CFA and the HANDLER. We ignore the CFA, extract the handler, and
5579 set a breakpoint there. */
5580 probe
= find_probe_by_pc (get_frame_pc (frame
), &objfile
);
5583 insert_exception_resume_from_probe (ecs
->event_thread
, probe
,
5588 func
= get_frame_function (frame
);
5592 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5595 struct block_iterator iter
;
5599 /* The exception breakpoint is a thread-specific breakpoint on
5600 the unwinder's debug hook, declared as:
5602 void _Unwind_DebugHook (void *cfa, void *handler);
5604 The CFA argument indicates the frame to which control is
5605 about to be transferred. HANDLER is the destination PC.
5607 We ignore the CFA and set a temporary breakpoint at HANDLER.
5608 This is not extremely efficient but it avoids issues in gdb
5609 with computing the DWARF CFA, and it also works even in weird
5610 cases such as throwing an exception from inside a signal
5613 b
= SYMBOL_BLOCK_VALUE (func
);
5614 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
5616 if (!SYMBOL_IS_ARGUMENT (sym
))
5623 insert_exception_resume_breakpoint (ecs
->event_thread
,
5632 stop_stepping (struct execution_control_state
*ecs
)
5635 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
5637 /* Let callers know we don't want to wait for the inferior anymore. */
5638 ecs
->wait_some_more
= 0;
5641 /* This function handles various cases where we need to continue
5642 waiting for the inferior. */
5643 /* (Used to be the keep_going: label in the old wait_for_inferior). */
5646 keep_going (struct execution_control_state
*ecs
)
5648 /* Make sure normal_stop is called if we get a QUIT handled before
5650 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
5652 /* Save the pc before execution, to compare with pc after stop. */
5653 ecs
->event_thread
->prev_pc
5654 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5656 /* If we did not do break;, it means we should keep running the
5657 inferior and not return to debugger. */
5659 if (ecs
->event_thread
->control
.trap_expected
5660 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5662 /* We took a signal (which we are supposed to pass through to
5663 the inferior, else we'd not get here) and we haven't yet
5664 gotten our trap. Simply continue. */
5666 discard_cleanups (old_cleanups
);
5667 resume (currently_stepping (ecs
->event_thread
),
5668 ecs
->event_thread
->suspend
.stop_signal
);
5672 /* Either the trap was not expected, but we are continuing
5673 anyway (the user asked that this signal be passed to the
5676 The signal was SIGTRAP, e.g. it was our signal, but we
5677 decided we should resume from it.
5679 We're going to run this baby now!
5681 Note that insert_breakpoints won't try to re-insert
5682 already inserted breakpoints. Therefore, we don't
5683 care if breakpoints were already inserted, or not. */
5685 if (ecs
->event_thread
->stepping_over_breakpoint
)
5687 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
5689 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
5690 /* Since we can't do a displaced step, we have to remove
5691 the breakpoint while we step it. To keep things
5692 simple, we remove them all. */
5693 remove_breakpoints ();
5697 volatile struct gdb_exception e
;
5699 /* Stop stepping when inserting breakpoints
5701 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5703 insert_breakpoints ();
5707 exception_print (gdb_stderr
, e
);
5708 stop_stepping (ecs
);
5713 ecs
->event_thread
->control
.trap_expected
5714 = ecs
->event_thread
->stepping_over_breakpoint
;
5716 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
5717 specifies that such a signal should be delivered to the
5720 Typically, this would occure when a user is debugging a
5721 target monitor on a simulator: the target monitor sets a
5722 breakpoint; the simulator encounters this break-point and
5723 halts the simulation handing control to GDB; GDB, noteing
5724 that the break-point isn't valid, returns control back to the
5725 simulator; the simulator then delivers the hardware
5726 equivalent of a SIGNAL_TRAP to the program being debugged. */
5728 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5729 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5730 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5732 discard_cleanups (old_cleanups
);
5733 resume (currently_stepping (ecs
->event_thread
),
5734 ecs
->event_thread
->suspend
.stop_signal
);
5737 prepare_to_wait (ecs
);
5740 /* This function normally comes after a resume, before
5741 handle_inferior_event exits. It takes care of any last bits of
5742 housekeeping, and sets the all-important wait_some_more flag. */
5745 prepare_to_wait (struct execution_control_state
*ecs
)
5748 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
5750 /* This is the old end of the while loop. Let everybody know we
5751 want to wait for the inferior some more and get called again
5753 ecs
->wait_some_more
= 1;
5756 /* Several print_*_reason functions to print why the inferior has stopped.
5757 We always print something when the inferior exits, or receives a signal.
5758 The rest of the cases are dealt with later on in normal_stop and
5759 print_it_typical. Ideally there should be a call to one of these
5760 print_*_reason functions functions from handle_inferior_event each time
5761 stop_stepping is called. */
5763 /* Print why the inferior has stopped.
5764 We are done with a step/next/si/ni command, print why the inferior has
5765 stopped. For now print nothing. Print a message only if not in the middle
5766 of doing a "step n" operation for n > 1. */
5769 print_end_stepping_range_reason (void)
5771 if ((!inferior_thread ()->step_multi
5772 || !inferior_thread ()->control
.stop_step
)
5773 && ui_out_is_mi_like_p (current_uiout
))
5774 ui_out_field_string (current_uiout
, "reason",
5775 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
5778 /* The inferior was terminated by a signal, print why it stopped. */
5781 print_signal_exited_reason (enum gdb_signal siggnal
)
5783 struct ui_out
*uiout
= current_uiout
;
5785 annotate_signalled ();
5786 if (ui_out_is_mi_like_p (uiout
))
5788 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
5789 ui_out_text (uiout
, "\nProgram terminated with signal ");
5790 annotate_signal_name ();
5791 ui_out_field_string (uiout
, "signal-name",
5792 gdb_signal_to_name (siggnal
));
5793 annotate_signal_name_end ();
5794 ui_out_text (uiout
, ", ");
5795 annotate_signal_string ();
5796 ui_out_field_string (uiout
, "signal-meaning",
5797 gdb_signal_to_string (siggnal
));
5798 annotate_signal_string_end ();
5799 ui_out_text (uiout
, ".\n");
5800 ui_out_text (uiout
, "The program no longer exists.\n");
5803 /* The inferior program is finished, print why it stopped. */
5806 print_exited_reason (int exitstatus
)
5808 struct inferior
*inf
= current_inferior ();
5809 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
5810 struct ui_out
*uiout
= current_uiout
;
5812 annotate_exited (exitstatus
);
5815 if (ui_out_is_mi_like_p (uiout
))
5816 ui_out_field_string (uiout
, "reason",
5817 async_reason_lookup (EXEC_ASYNC_EXITED
));
5818 ui_out_text (uiout
, "[Inferior ");
5819 ui_out_text (uiout
, plongest (inf
->num
));
5820 ui_out_text (uiout
, " (");
5821 ui_out_text (uiout
, pidstr
);
5822 ui_out_text (uiout
, ") exited with code ");
5823 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
5824 ui_out_text (uiout
, "]\n");
5828 if (ui_out_is_mi_like_p (uiout
))
5830 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
5831 ui_out_text (uiout
, "[Inferior ");
5832 ui_out_text (uiout
, plongest (inf
->num
));
5833 ui_out_text (uiout
, " (");
5834 ui_out_text (uiout
, pidstr
);
5835 ui_out_text (uiout
, ") exited normally]\n");
5837 /* Support the --return-child-result option. */
5838 return_child_result_value
= exitstatus
;
5841 /* Signal received, print why the inferior has stopped. The signal table
5842 tells us to print about it. */
5845 print_signal_received_reason (enum gdb_signal siggnal
)
5847 struct ui_out
*uiout
= current_uiout
;
5851 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
5853 struct thread_info
*t
= inferior_thread ();
5855 ui_out_text (uiout
, "\n[");
5856 ui_out_field_string (uiout
, "thread-name",
5857 target_pid_to_str (t
->ptid
));
5858 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
5859 ui_out_text (uiout
, " stopped");
5863 ui_out_text (uiout
, "\nProgram received signal ");
5864 annotate_signal_name ();
5865 if (ui_out_is_mi_like_p (uiout
))
5867 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
5868 ui_out_field_string (uiout
, "signal-name",
5869 gdb_signal_to_name (siggnal
));
5870 annotate_signal_name_end ();
5871 ui_out_text (uiout
, ", ");
5872 annotate_signal_string ();
5873 ui_out_field_string (uiout
, "signal-meaning",
5874 gdb_signal_to_string (siggnal
));
5875 annotate_signal_string_end ();
5877 ui_out_text (uiout
, ".\n");
5880 /* Reverse execution: target ran out of history info, print why the inferior
5884 print_no_history_reason (void)
5886 ui_out_text (current_uiout
, "\nNo more reverse-execution history.\n");
5889 /* Here to return control to GDB when the inferior stops for real.
5890 Print appropriate messages, remove breakpoints, give terminal our modes.
5892 STOP_PRINT_FRAME nonzero means print the executing frame
5893 (pc, function, args, file, line number and line text).
5894 BREAKPOINTS_FAILED nonzero means stop was due to error
5895 attempting to insert breakpoints. */
5900 struct target_waitstatus last
;
5902 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
5904 get_last_target_status (&last_ptid
, &last
);
5906 /* If an exception is thrown from this point on, make sure to
5907 propagate GDB's knowledge of the executing state to the
5908 frontend/user running state. A QUIT is an easy exception to see
5909 here, so do this before any filtered output. */
5911 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
5912 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
5913 && last
.kind
!= TARGET_WAITKIND_EXITED
5914 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
5915 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
5917 /* In non-stop mode, we don't want GDB to switch threads behind the
5918 user's back, to avoid races where the user is typing a command to
5919 apply to thread x, but GDB switches to thread y before the user
5920 finishes entering the command. */
5922 /* As with the notification of thread events, we want to delay
5923 notifying the user that we've switched thread context until
5924 the inferior actually stops.
5926 There's no point in saying anything if the inferior has exited.
5927 Note that SIGNALLED here means "exited with a signal", not
5928 "received a signal". */
5930 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
5931 && target_has_execution
5932 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5933 && last
.kind
!= TARGET_WAITKIND_EXITED
5934 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
5936 target_terminal_ours_for_output ();
5937 printf_filtered (_("[Switching to %s]\n"),
5938 target_pid_to_str (inferior_ptid
));
5939 annotate_thread_changed ();
5940 previous_inferior_ptid
= inferior_ptid
;
5943 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
5945 gdb_assert (sync_execution
|| !target_can_async_p ());
5947 target_terminal_ours_for_output ();
5948 printf_filtered (_("No unwaited-for children left.\n"));
5951 if (!breakpoints_always_inserted_mode () && target_has_execution
)
5953 if (remove_breakpoints ())
5955 target_terminal_ours_for_output ();
5956 printf_filtered (_("Cannot remove breakpoints because "
5957 "program is no longer writable.\nFurther "
5958 "execution is probably impossible.\n"));
5962 /* If an auto-display called a function and that got a signal,
5963 delete that auto-display to avoid an infinite recursion. */
5965 if (stopped_by_random_signal
)
5966 disable_current_display ();
5968 /* Don't print a message if in the middle of doing a "step n"
5969 operation for n > 1 */
5970 if (target_has_execution
5971 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5972 && last
.kind
!= TARGET_WAITKIND_EXITED
5973 && inferior_thread ()->step_multi
5974 && inferior_thread ()->control
.stop_step
)
5977 target_terminal_ours ();
5978 async_enable_stdin ();
5980 /* Set the current source location. This will also happen if we
5981 display the frame below, but the current SAL will be incorrect
5982 during a user hook-stop function. */
5983 if (has_stack_frames () && !stop_stack_dummy
)
5984 set_current_sal_from_frame (get_current_frame (), 1);
5986 /* Let the user/frontend see the threads as stopped. */
5987 do_cleanups (old_chain
);
5989 /* Look up the hook_stop and run it (CLI internally handles problem
5990 of stop_command's pre-hook not existing). */
5992 catch_errors (hook_stop_stub
, stop_command
,
5993 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
5995 if (!has_stack_frames ())
5998 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
5999 || last
.kind
== TARGET_WAITKIND_EXITED
)
6002 /* Select innermost stack frame - i.e., current frame is frame 0,
6003 and current location is based on that.
6004 Don't do this on return from a stack dummy routine,
6005 or if the program has exited. */
6007 if (!stop_stack_dummy
)
6009 select_frame (get_current_frame ());
6011 /* Print current location without a level number, if
6012 we have changed functions or hit a breakpoint.
6013 Print source line if we have one.
6014 bpstat_print() contains the logic deciding in detail
6015 what to print, based on the event(s) that just occurred. */
6017 /* If --batch-silent is enabled then there's no need to print the current
6018 source location, and to try risks causing an error message about
6019 missing source files. */
6020 if (stop_print_frame
&& !batch_silent
)
6024 int do_frame_printing
= 1;
6025 struct thread_info
*tp
= inferior_thread ();
6027 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, last
.kind
);
6031 /* FIXME: cagney/2002-12-01: Given that a frame ID does
6032 (or should) carry around the function and does (or
6033 should) use that when doing a frame comparison. */
6034 if (tp
->control
.stop_step
6035 && frame_id_eq (tp
->control
.step_frame_id
,
6036 get_frame_id (get_current_frame ()))
6037 && step_start_function
== find_pc_function (stop_pc
))
6038 source_flag
= SRC_LINE
; /* Finished step, just
6039 print source line. */
6041 source_flag
= SRC_AND_LOC
; /* Print location and
6044 case PRINT_SRC_AND_LOC
:
6045 source_flag
= SRC_AND_LOC
; /* Print location and
6048 case PRINT_SRC_ONLY
:
6049 source_flag
= SRC_LINE
;
6052 source_flag
= SRC_LINE
; /* something bogus */
6053 do_frame_printing
= 0;
6056 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6059 /* The behavior of this routine with respect to the source
6061 SRC_LINE: Print only source line
6062 LOCATION: Print only location
6063 SRC_AND_LOC: Print location and source line. */
6064 if (do_frame_printing
)
6065 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
6067 /* Display the auto-display expressions. */
6072 /* Save the function value return registers, if we care.
6073 We might be about to restore their previous contents. */
6074 if (inferior_thread ()->control
.proceed_to_finish
6075 && execution_direction
!= EXEC_REVERSE
)
6077 /* This should not be necessary. */
6079 regcache_xfree (stop_registers
);
6081 /* NB: The copy goes through to the target picking up the value of
6082 all the registers. */
6083 stop_registers
= regcache_dup (get_current_regcache ());
6086 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6088 /* Pop the empty frame that contains the stack dummy.
6089 This also restores inferior state prior to the call
6090 (struct infcall_suspend_state). */
6091 struct frame_info
*frame
= get_current_frame ();
6093 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6095 /* frame_pop() calls reinit_frame_cache as the last thing it
6096 does which means there's currently no selected frame. We
6097 don't need to re-establish a selected frame if the dummy call
6098 returns normally, that will be done by
6099 restore_infcall_control_state. However, we do have to handle
6100 the case where the dummy call is returning after being
6101 stopped (e.g. the dummy call previously hit a breakpoint).
6102 We can't know which case we have so just always re-establish
6103 a selected frame here. */
6104 select_frame (get_current_frame ());
6108 annotate_stopped ();
6110 /* Suppress the stop observer if we're in the middle of:
6112 - a step n (n > 1), as there still more steps to be done.
6114 - a "finish" command, as the observer will be called in
6115 finish_command_continuation, so it can include the inferior
6116 function's return value.
6118 - calling an inferior function, as we pretend we inferior didn't
6119 run at all. The return value of the call is handled by the
6120 expression evaluator, through call_function_by_hand. */
6122 if (!target_has_execution
6123 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6124 || last
.kind
== TARGET_WAITKIND_EXITED
6125 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6126 || (!(inferior_thread ()->step_multi
6127 && inferior_thread ()->control
.stop_step
)
6128 && !(inferior_thread ()->control
.stop_bpstat
6129 && inferior_thread ()->control
.proceed_to_finish
)
6130 && !inferior_thread ()->control
.in_infcall
))
6132 if (!ptid_equal (inferior_ptid
, null_ptid
))
6133 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6136 observer_notify_normal_stop (NULL
, stop_print_frame
);
6139 if (target_has_execution
)
6141 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6142 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6143 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6144 Delete any breakpoint that is to be deleted at the next stop. */
6145 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6148 /* Try to get rid of automatically added inferiors that are no
6149 longer needed. Keeping those around slows down things linearly.
6150 Note that this never removes the current inferior. */
6155 hook_stop_stub (void *cmd
)
6157 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6162 signal_stop_state (int signo
)
6164 return signal_stop
[signo
];
6168 signal_print_state (int signo
)
6170 return signal_print
[signo
];
6174 signal_pass_state (int signo
)
6176 return signal_program
[signo
];
6180 signal_cache_update (int signo
)
6184 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6185 signal_cache_update (signo
);
6190 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6191 && signal_print
[signo
] == 0
6192 && signal_program
[signo
] == 1);
6196 signal_stop_update (int signo
, int state
)
6198 int ret
= signal_stop
[signo
];
6200 signal_stop
[signo
] = state
;
6201 signal_cache_update (signo
);
6206 signal_print_update (int signo
, int state
)
6208 int ret
= signal_print
[signo
];
6210 signal_print
[signo
] = state
;
6211 signal_cache_update (signo
);
6216 signal_pass_update (int signo
, int state
)
6218 int ret
= signal_program
[signo
];
6220 signal_program
[signo
] = state
;
6221 signal_cache_update (signo
);
6226 sig_print_header (void)
6228 printf_filtered (_("Signal Stop\tPrint\tPass "
6229 "to program\tDescription\n"));
6233 sig_print_info (enum gdb_signal oursig
)
6235 const char *name
= gdb_signal_to_name (oursig
);
6236 int name_padding
= 13 - strlen (name
);
6238 if (name_padding
<= 0)
6241 printf_filtered ("%s", name
);
6242 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6243 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6244 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6245 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6246 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6249 /* Specify how various signals in the inferior should be handled. */
6252 handle_command (char *args
, int from_tty
)
6255 int digits
, wordlen
;
6256 int sigfirst
, signum
, siglast
;
6257 enum gdb_signal oursig
;
6260 unsigned char *sigs
;
6261 struct cleanup
*old_chain
;
6265 error_no_arg (_("signal to handle"));
6268 /* Allocate and zero an array of flags for which signals to handle. */
6270 nsigs
= (int) GDB_SIGNAL_LAST
;
6271 sigs
= (unsigned char *) alloca (nsigs
);
6272 memset (sigs
, 0, nsigs
);
6274 /* Break the command line up into args. */
6276 argv
= gdb_buildargv (args
);
6277 old_chain
= make_cleanup_freeargv (argv
);
6279 /* Walk through the args, looking for signal oursigs, signal names, and
6280 actions. Signal numbers and signal names may be interspersed with
6281 actions, with the actions being performed for all signals cumulatively
6282 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6284 while (*argv
!= NULL
)
6286 wordlen
= strlen (*argv
);
6287 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6291 sigfirst
= siglast
= -1;
6293 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6295 /* Apply action to all signals except those used by the
6296 debugger. Silently skip those. */
6299 siglast
= nsigs
- 1;
6301 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6303 SET_SIGS (nsigs
, sigs
, signal_stop
);
6304 SET_SIGS (nsigs
, sigs
, signal_print
);
6306 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6308 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6310 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6312 SET_SIGS (nsigs
, sigs
, signal_print
);
6314 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6316 SET_SIGS (nsigs
, sigs
, signal_program
);
6318 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6320 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6322 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6324 SET_SIGS (nsigs
, sigs
, signal_program
);
6326 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6328 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6329 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6331 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6333 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6335 else if (digits
> 0)
6337 /* It is numeric. The numeric signal refers to our own
6338 internal signal numbering from target.h, not to host/target
6339 signal number. This is a feature; users really should be
6340 using symbolic names anyway, and the common ones like
6341 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6343 sigfirst
= siglast
= (int)
6344 gdb_signal_from_command (atoi (*argv
));
6345 if ((*argv
)[digits
] == '-')
6348 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6350 if (sigfirst
> siglast
)
6352 /* Bet he didn't figure we'd think of this case... */
6360 oursig
= gdb_signal_from_name (*argv
);
6361 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
6363 sigfirst
= siglast
= (int) oursig
;
6367 /* Not a number and not a recognized flag word => complain. */
6368 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6372 /* If any signal numbers or symbol names were found, set flags for
6373 which signals to apply actions to. */
6375 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6377 switch ((enum gdb_signal
) signum
)
6379 case GDB_SIGNAL_TRAP
:
6380 case GDB_SIGNAL_INT
:
6381 if (!allsigs
&& !sigs
[signum
])
6383 if (query (_("%s is used by the debugger.\n\
6384 Are you sure you want to change it? "),
6385 gdb_signal_to_name ((enum gdb_signal
) signum
)))
6391 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6392 gdb_flush (gdb_stdout
);
6397 case GDB_SIGNAL_DEFAULT
:
6398 case GDB_SIGNAL_UNKNOWN
:
6399 /* Make sure that "all" doesn't print these. */
6410 for (signum
= 0; signum
< nsigs
; signum
++)
6413 signal_cache_update (-1);
6414 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6415 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
6419 /* Show the results. */
6420 sig_print_header ();
6421 for (; signum
< nsigs
; signum
++)
6423 sig_print_info (signum
);
6429 do_cleanups (old_chain
);
6433 xdb_handle_command (char *args
, int from_tty
)
6436 struct cleanup
*old_chain
;
6439 error_no_arg (_("xdb command"));
6441 /* Break the command line up into args. */
6443 argv
= gdb_buildargv (args
);
6444 old_chain
= make_cleanup_freeargv (argv
);
6445 if (argv
[1] != (char *) NULL
)
6450 bufLen
= strlen (argv
[0]) + 20;
6451 argBuf
= (char *) xmalloc (bufLen
);
6455 enum gdb_signal oursig
;
6457 oursig
= gdb_signal_from_name (argv
[0]);
6458 memset (argBuf
, 0, bufLen
);
6459 if (strcmp (argv
[1], "Q") == 0)
6460 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6463 if (strcmp (argv
[1], "s") == 0)
6465 if (!signal_stop
[oursig
])
6466 sprintf (argBuf
, "%s %s", argv
[0], "stop");
6468 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
6470 else if (strcmp (argv
[1], "i") == 0)
6472 if (!signal_program
[oursig
])
6473 sprintf (argBuf
, "%s %s", argv
[0], "pass");
6475 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
6477 else if (strcmp (argv
[1], "r") == 0)
6479 if (!signal_print
[oursig
])
6480 sprintf (argBuf
, "%s %s", argv
[0], "print");
6482 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6488 handle_command (argBuf
, from_tty
);
6490 printf_filtered (_("Invalid signal handling flag.\n"));
6495 do_cleanups (old_chain
);
6499 gdb_signal_from_command (int num
)
6501 if (num
>= 1 && num
<= 15)
6502 return (enum gdb_signal
) num
;
6503 error (_("Only signals 1-15 are valid as numeric signals.\n\
6504 Use \"info signals\" for a list of symbolic signals."));
6507 /* Print current contents of the tables set by the handle command.
6508 It is possible we should just be printing signals actually used
6509 by the current target (but for things to work right when switching
6510 targets, all signals should be in the signal tables). */
6513 signals_info (char *signum_exp
, int from_tty
)
6515 enum gdb_signal oursig
;
6517 sig_print_header ();
6521 /* First see if this is a symbol name. */
6522 oursig
= gdb_signal_from_name (signum_exp
);
6523 if (oursig
== GDB_SIGNAL_UNKNOWN
)
6525 /* No, try numeric. */
6527 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
6529 sig_print_info (oursig
);
6533 printf_filtered ("\n");
6534 /* These ugly casts brought to you by the native VAX compiler. */
6535 for (oursig
= GDB_SIGNAL_FIRST
;
6536 (int) oursig
< (int) GDB_SIGNAL_LAST
;
6537 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
6541 if (oursig
!= GDB_SIGNAL_UNKNOWN
6542 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
6543 sig_print_info (oursig
);
6546 printf_filtered (_("\nUse the \"handle\" command "
6547 "to change these tables.\n"));
6550 /* Check if it makes sense to read $_siginfo from the current thread
6551 at this point. If not, throw an error. */
6554 validate_siginfo_access (void)
6556 /* No current inferior, no siginfo. */
6557 if (ptid_equal (inferior_ptid
, null_ptid
))
6558 error (_("No thread selected."));
6560 /* Don't try to read from a dead thread. */
6561 if (is_exited (inferior_ptid
))
6562 error (_("The current thread has terminated"));
6564 /* ... or from a spinning thread. */
6565 if (is_running (inferior_ptid
))
6566 error (_("Selected thread is running."));
6569 /* The $_siginfo convenience variable is a bit special. We don't know
6570 for sure the type of the value until we actually have a chance to
6571 fetch the data. The type can change depending on gdbarch, so it is
6572 also dependent on which thread you have selected.
6574 1. making $_siginfo be an internalvar that creates a new value on
6577 2. making the value of $_siginfo be an lval_computed value. */
6579 /* This function implements the lval_computed support for reading a
6583 siginfo_value_read (struct value
*v
)
6585 LONGEST transferred
;
6587 validate_siginfo_access ();
6590 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
6592 value_contents_all_raw (v
),
6594 TYPE_LENGTH (value_type (v
)));
6596 if (transferred
!= TYPE_LENGTH (value_type (v
)))
6597 error (_("Unable to read siginfo"));
6600 /* This function implements the lval_computed support for writing a
6604 siginfo_value_write (struct value
*v
, struct value
*fromval
)
6606 LONGEST transferred
;
6608 validate_siginfo_access ();
6610 transferred
= target_write (¤t_target
,
6611 TARGET_OBJECT_SIGNAL_INFO
,
6613 value_contents_all_raw (fromval
),
6615 TYPE_LENGTH (value_type (fromval
)));
6617 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
6618 error (_("Unable to write siginfo"));
6621 static const struct lval_funcs siginfo_value_funcs
=
6627 /* Return a new value with the correct type for the siginfo object of
6628 the current thread using architecture GDBARCH. Return a void value
6629 if there's no object available. */
6631 static struct value
*
6632 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
6635 if (target_has_stack
6636 && !ptid_equal (inferior_ptid
, null_ptid
)
6637 && gdbarch_get_siginfo_type_p (gdbarch
))
6639 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6641 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
6644 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
6648 /* infcall_suspend_state contains state about the program itself like its
6649 registers and any signal it received when it last stopped.
6650 This state must be restored regardless of how the inferior function call
6651 ends (either successfully, or after it hits a breakpoint or signal)
6652 if the program is to properly continue where it left off. */
6654 struct infcall_suspend_state
6656 struct thread_suspend_state thread_suspend
;
6657 struct inferior_suspend_state inferior_suspend
;
6661 struct regcache
*registers
;
6663 /* Format of SIGINFO_DATA or NULL if it is not present. */
6664 struct gdbarch
*siginfo_gdbarch
;
6666 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
6667 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
6668 content would be invalid. */
6669 gdb_byte
*siginfo_data
;
6672 struct infcall_suspend_state
*
6673 save_infcall_suspend_state (void)
6675 struct infcall_suspend_state
*inf_state
;
6676 struct thread_info
*tp
= inferior_thread ();
6677 struct inferior
*inf
= current_inferior ();
6678 struct regcache
*regcache
= get_current_regcache ();
6679 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6680 gdb_byte
*siginfo_data
= NULL
;
6682 if (gdbarch_get_siginfo_type_p (gdbarch
))
6684 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6685 size_t len
= TYPE_LENGTH (type
);
6686 struct cleanup
*back_to
;
6688 siginfo_data
= xmalloc (len
);
6689 back_to
= make_cleanup (xfree
, siginfo_data
);
6691 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6692 siginfo_data
, 0, len
) == len
)
6693 discard_cleanups (back_to
);
6696 /* Errors ignored. */
6697 do_cleanups (back_to
);
6698 siginfo_data
= NULL
;
6702 inf_state
= XZALLOC (struct infcall_suspend_state
);
6706 inf_state
->siginfo_gdbarch
= gdbarch
;
6707 inf_state
->siginfo_data
= siginfo_data
;
6710 inf_state
->thread_suspend
= tp
->suspend
;
6711 inf_state
->inferior_suspend
= inf
->suspend
;
6713 /* run_inferior_call will not use the signal due to its `proceed' call with
6714 GDB_SIGNAL_0 anyway. */
6715 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6717 inf_state
->stop_pc
= stop_pc
;
6719 inf_state
->registers
= regcache_dup (regcache
);
6724 /* Restore inferior session state to INF_STATE. */
6727 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6729 struct thread_info
*tp
= inferior_thread ();
6730 struct inferior
*inf
= current_inferior ();
6731 struct regcache
*regcache
= get_current_regcache ();
6732 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6734 tp
->suspend
= inf_state
->thread_suspend
;
6735 inf
->suspend
= inf_state
->inferior_suspend
;
6737 stop_pc
= inf_state
->stop_pc
;
6739 if (inf_state
->siginfo_gdbarch
== gdbarch
)
6741 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6742 size_t len
= TYPE_LENGTH (type
);
6744 /* Errors ignored. */
6745 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6746 inf_state
->siginfo_data
, 0, len
);
6749 /* The inferior can be gone if the user types "print exit(0)"
6750 (and perhaps other times). */
6751 if (target_has_execution
)
6752 /* NB: The register write goes through to the target. */
6753 regcache_cpy (regcache
, inf_state
->registers
);
6755 discard_infcall_suspend_state (inf_state
);
6759 do_restore_infcall_suspend_state_cleanup (void *state
)
6761 restore_infcall_suspend_state (state
);
6765 make_cleanup_restore_infcall_suspend_state
6766 (struct infcall_suspend_state
*inf_state
)
6768 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
6772 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6774 regcache_xfree (inf_state
->registers
);
6775 xfree (inf_state
->siginfo_data
);
6780 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
6782 return inf_state
->registers
;
6785 /* infcall_control_state contains state regarding gdb's control of the
6786 inferior itself like stepping control. It also contains session state like
6787 the user's currently selected frame. */
6789 struct infcall_control_state
6791 struct thread_control_state thread_control
;
6792 struct inferior_control_state inferior_control
;
6795 enum stop_stack_kind stop_stack_dummy
;
6796 int stopped_by_random_signal
;
6797 int stop_after_trap
;
6799 /* ID if the selected frame when the inferior function call was made. */
6800 struct frame_id selected_frame_id
;
6803 /* Save all of the information associated with the inferior<==>gdb
6806 struct infcall_control_state
*
6807 save_infcall_control_state (void)
6809 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
6810 struct thread_info
*tp
= inferior_thread ();
6811 struct inferior
*inf
= current_inferior ();
6813 inf_status
->thread_control
= tp
->control
;
6814 inf_status
->inferior_control
= inf
->control
;
6816 tp
->control
.step_resume_breakpoint
= NULL
;
6817 tp
->control
.exception_resume_breakpoint
= NULL
;
6819 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
6820 chain. If caller's caller is walking the chain, they'll be happier if we
6821 hand them back the original chain when restore_infcall_control_state is
6823 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
6826 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
6827 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
6828 inf_status
->stop_after_trap
= stop_after_trap
;
6830 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
6836 restore_selected_frame (void *args
)
6838 struct frame_id
*fid
= (struct frame_id
*) args
;
6839 struct frame_info
*frame
;
6841 frame
= frame_find_by_id (*fid
);
6843 /* If inf_status->selected_frame_id is NULL, there was no previously
6847 warning (_("Unable to restore previously selected frame."));
6851 select_frame (frame
);
6856 /* Restore inferior session state to INF_STATUS. */
6859 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
6861 struct thread_info
*tp
= inferior_thread ();
6862 struct inferior
*inf
= current_inferior ();
6864 if (tp
->control
.step_resume_breakpoint
)
6865 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
6867 if (tp
->control
.exception_resume_breakpoint
)
6868 tp
->control
.exception_resume_breakpoint
->disposition
6869 = disp_del_at_next_stop
;
6871 /* Handle the bpstat_copy of the chain. */
6872 bpstat_clear (&tp
->control
.stop_bpstat
);
6874 tp
->control
= inf_status
->thread_control
;
6875 inf
->control
= inf_status
->inferior_control
;
6878 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
6879 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
6880 stop_after_trap
= inf_status
->stop_after_trap
;
6882 if (target_has_stack
)
6884 /* The point of catch_errors is that if the stack is clobbered,
6885 walking the stack might encounter a garbage pointer and
6886 error() trying to dereference it. */
6888 (restore_selected_frame
, &inf_status
->selected_frame_id
,
6889 "Unable to restore previously selected frame:\n",
6890 RETURN_MASK_ERROR
) == 0)
6891 /* Error in restoring the selected frame. Select the innermost
6893 select_frame (get_current_frame ());
6900 do_restore_infcall_control_state_cleanup (void *sts
)
6902 restore_infcall_control_state (sts
);
6906 make_cleanup_restore_infcall_control_state
6907 (struct infcall_control_state
*inf_status
)
6909 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
6913 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
6915 if (inf_status
->thread_control
.step_resume_breakpoint
)
6916 inf_status
->thread_control
.step_resume_breakpoint
->disposition
6917 = disp_del_at_next_stop
;
6919 if (inf_status
->thread_control
.exception_resume_breakpoint
)
6920 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
6921 = disp_del_at_next_stop
;
6923 /* See save_infcall_control_state for info on stop_bpstat. */
6924 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
6930 ptid_match (ptid_t ptid
, ptid_t filter
)
6932 if (ptid_equal (filter
, minus_one_ptid
))
6934 if (ptid_is_pid (filter
)
6935 && ptid_get_pid (ptid
) == ptid_get_pid (filter
))
6937 else if (ptid_equal (ptid
, filter
))
6943 /* restore_inferior_ptid() will be used by the cleanup machinery
6944 to restore the inferior_ptid value saved in a call to
6945 save_inferior_ptid(). */
6948 restore_inferior_ptid (void *arg
)
6950 ptid_t
*saved_ptid_ptr
= arg
;
6952 inferior_ptid
= *saved_ptid_ptr
;
6956 /* Save the value of inferior_ptid so that it may be restored by a
6957 later call to do_cleanups(). Returns the struct cleanup pointer
6958 needed for later doing the cleanup. */
6961 save_inferior_ptid (void)
6963 ptid_t
*saved_ptid_ptr
;
6965 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
6966 *saved_ptid_ptr
= inferior_ptid
;
6967 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
6971 /* User interface for reverse debugging:
6972 Set exec-direction / show exec-direction commands
6973 (returns error unless target implements to_set_exec_direction method). */
6975 int execution_direction
= EXEC_FORWARD
;
6976 static const char exec_forward
[] = "forward";
6977 static const char exec_reverse
[] = "reverse";
6978 static const char *exec_direction
= exec_forward
;
6979 static const char *const exec_direction_names
[] = {
6986 set_exec_direction_func (char *args
, int from_tty
,
6987 struct cmd_list_element
*cmd
)
6989 if (target_can_execute_reverse
)
6991 if (!strcmp (exec_direction
, exec_forward
))
6992 execution_direction
= EXEC_FORWARD
;
6993 else if (!strcmp (exec_direction
, exec_reverse
))
6994 execution_direction
= EXEC_REVERSE
;
6998 exec_direction
= exec_forward
;
6999 error (_("Target does not support this operation."));
7004 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7005 struct cmd_list_element
*cmd
, const char *value
)
7007 switch (execution_direction
) {
7009 fprintf_filtered (out
, _("Forward.\n"));
7012 fprintf_filtered (out
, _("Reverse.\n"));
7015 internal_error (__FILE__
, __LINE__
,
7016 _("bogus execution_direction value: %d"),
7017 (int) execution_direction
);
7021 /* User interface for non-stop mode. */
7026 set_non_stop (char *args
, int from_tty
,
7027 struct cmd_list_element
*c
)
7029 if (target_has_execution
)
7031 non_stop_1
= non_stop
;
7032 error (_("Cannot change this setting while the inferior is running."));
7035 non_stop
= non_stop_1
;
7039 show_non_stop (struct ui_file
*file
, int from_tty
,
7040 struct cmd_list_element
*c
, const char *value
)
7042 fprintf_filtered (file
,
7043 _("Controlling the inferior in non-stop mode is %s.\n"),
7048 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7049 struct cmd_list_element
*c
, const char *value
)
7051 fprintf_filtered (file
, _("Resuming the execution of threads "
7052 "of all processes is %s.\n"), value
);
7055 /* Implementation of `siginfo' variable. */
7057 static const struct internalvar_funcs siginfo_funcs
=
7065 _initialize_infrun (void)
7070 add_info ("signals", signals_info
, _("\
7071 What debugger does when program gets various signals.\n\
7072 Specify a signal as argument to print info on that signal only."));
7073 add_info_alias ("handle", "signals", 0);
7075 add_com ("handle", class_run
, handle_command
, _("\
7076 Specify how to handle a signal.\n\
7077 Args are signals and actions to apply to those signals.\n\
7078 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7079 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7080 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7081 The special arg \"all\" is recognized to mean all signals except those\n\
7082 used by the debugger, typically SIGTRAP and SIGINT.\n\
7083 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7084 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7085 Stop means reenter debugger if this signal happens (implies print).\n\
7086 Print means print a message if this signal happens.\n\
7087 Pass means let program see this signal; otherwise program doesn't know.\n\
7088 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7089 Pass and Stop may be combined."));
7092 add_com ("lz", class_info
, signals_info
, _("\
7093 What debugger does when program gets various signals.\n\
7094 Specify a signal as argument to print info on that signal only."));
7095 add_com ("z", class_run
, xdb_handle_command
, _("\
7096 Specify how to handle a signal.\n\
7097 Args are signals and actions to apply to those signals.\n\
7098 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7099 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7100 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7101 The special arg \"all\" is recognized to mean all signals except those\n\
7102 used by the debugger, typically SIGTRAP and SIGINT.\n\
7103 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7104 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7105 nopass), \"Q\" (noprint)\n\
7106 Stop means reenter debugger if this signal happens (implies print).\n\
7107 Print means print a message if this signal happens.\n\
7108 Pass means let program see this signal; otherwise program doesn't know.\n\
7109 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7110 Pass and Stop may be combined."));
7114 stop_command
= add_cmd ("stop", class_obscure
,
7115 not_just_help_class_command
, _("\
7116 There is no `stop' command, but you can set a hook on `stop'.\n\
7117 This allows you to set a list of commands to be run each time execution\n\
7118 of the program stops."), &cmdlist
);
7120 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7121 Set inferior debugging."), _("\
7122 Show inferior debugging."), _("\
7123 When non-zero, inferior specific debugging is enabled."),
7126 &setdebuglist
, &showdebuglist
);
7128 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7129 &debug_displaced
, _("\
7130 Set displaced stepping debugging."), _("\
7131 Show displaced stepping debugging."), _("\
7132 When non-zero, displaced stepping specific debugging is enabled."),
7134 show_debug_displaced
,
7135 &setdebuglist
, &showdebuglist
);
7137 add_setshow_boolean_cmd ("non-stop", no_class
,
7139 Set whether gdb controls the inferior in non-stop mode."), _("\
7140 Show whether gdb controls the inferior in non-stop mode."), _("\
7141 When debugging a multi-threaded program and this setting is\n\
7142 off (the default, also called all-stop mode), when one thread stops\n\
7143 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7144 all other threads in the program while you interact with the thread of\n\
7145 interest. When you continue or step a thread, you can allow the other\n\
7146 threads to run, or have them remain stopped, but while you inspect any\n\
7147 thread's state, all threads stop.\n\
7149 In non-stop mode, when one thread stops, other threads can continue\n\
7150 to run freely. You'll be able to step each thread independently,\n\
7151 leave it stopped or free to run as needed."),
7157 numsigs
= (int) GDB_SIGNAL_LAST
;
7158 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7159 signal_print
= (unsigned char *)
7160 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7161 signal_program
= (unsigned char *)
7162 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7163 signal_pass
= (unsigned char *)
7164 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7165 for (i
= 0; i
< numsigs
; i
++)
7168 signal_print
[i
] = 1;
7169 signal_program
[i
] = 1;
7172 /* Signals caused by debugger's own actions
7173 should not be given to the program afterwards. */
7174 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7175 signal_program
[GDB_SIGNAL_INT
] = 0;
7177 /* Signals that are not errors should not normally enter the debugger. */
7178 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7179 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7180 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7181 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7182 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7183 signal_print
[GDB_SIGNAL_PROF
] = 0;
7184 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7185 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7186 signal_stop
[GDB_SIGNAL_IO
] = 0;
7187 signal_print
[GDB_SIGNAL_IO
] = 0;
7188 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7189 signal_print
[GDB_SIGNAL_POLL
] = 0;
7190 signal_stop
[GDB_SIGNAL_URG
] = 0;
7191 signal_print
[GDB_SIGNAL_URG
] = 0;
7192 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7193 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7194 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7195 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7197 /* These signals are used internally by user-level thread
7198 implementations. (See signal(5) on Solaris.) Like the above
7199 signals, a healthy program receives and handles them as part of
7200 its normal operation. */
7201 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7202 signal_print
[GDB_SIGNAL_LWP
] = 0;
7203 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7204 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7205 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7206 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7208 /* Update cached state. */
7209 signal_cache_update (-1);
7211 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7212 &stop_on_solib_events
, _("\
7213 Set stopping for shared library events."), _("\
7214 Show stopping for shared library events."), _("\
7215 If nonzero, gdb will give control to the user when the dynamic linker\n\
7216 notifies gdb of shared library events. The most common event of interest\n\
7217 to the user would be loading/unloading of a new library."),
7219 show_stop_on_solib_events
,
7220 &setlist
, &showlist
);
7222 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7223 follow_fork_mode_kind_names
,
7224 &follow_fork_mode_string
, _("\
7225 Set debugger response to a program call of fork or vfork."), _("\
7226 Show debugger response to a program call of fork or vfork."), _("\
7227 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7228 parent - the original process is debugged after a fork\n\
7229 child - the new process is debugged after a fork\n\
7230 The unfollowed process will continue to run.\n\
7231 By default, the debugger will follow the parent process."),
7233 show_follow_fork_mode_string
,
7234 &setlist
, &showlist
);
7236 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7237 follow_exec_mode_names
,
7238 &follow_exec_mode_string
, _("\
7239 Set debugger response to a program call of exec."), _("\
7240 Show debugger response to a program call of exec."), _("\
7241 An exec call replaces the program image of a process.\n\
7243 follow-exec-mode can be:\n\
7245 new - the debugger creates a new inferior and rebinds the process\n\
7246 to this new inferior. The program the process was running before\n\
7247 the exec call can be restarted afterwards by restarting the original\n\
7250 same - the debugger keeps the process bound to the same inferior.\n\
7251 The new executable image replaces the previous executable loaded in\n\
7252 the inferior. Restarting the inferior after the exec call restarts\n\
7253 the executable the process was running after the exec call.\n\
7255 By default, the debugger will use the same inferior."),
7257 show_follow_exec_mode_string
,
7258 &setlist
, &showlist
);
7260 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7261 scheduler_enums
, &scheduler_mode
, _("\
7262 Set mode for locking scheduler during execution."), _("\
7263 Show mode for locking scheduler during execution."), _("\
7264 off == no locking (threads may preempt at any time)\n\
7265 on == full locking (no thread except the current thread may run)\n\
7266 step == scheduler locked during every single-step operation.\n\
7267 In this mode, no other thread may run during a step command.\n\
7268 Other threads may run while stepping over a function call ('next')."),
7269 set_schedlock_func
, /* traps on target vector */
7270 show_scheduler_mode
,
7271 &setlist
, &showlist
);
7273 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7274 Set mode for resuming threads of all processes."), _("\
7275 Show mode for resuming threads of all processes."), _("\
7276 When on, execution commands (such as 'continue' or 'next') resume all\n\
7277 threads of all processes. When off (which is the default), execution\n\
7278 commands only resume the threads of the current process. The set of\n\
7279 threads that are resumed is further refined by the scheduler-locking\n\
7280 mode (see help set scheduler-locking)."),
7282 show_schedule_multiple
,
7283 &setlist
, &showlist
);
7285 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7286 Set mode of the step operation."), _("\
7287 Show mode of the step operation."), _("\
7288 When set, doing a step over a function without debug line information\n\
7289 will stop at the first instruction of that function. Otherwise, the\n\
7290 function is skipped and the step command stops at a different source line."),
7292 show_step_stop_if_no_debug
,
7293 &setlist
, &showlist
);
7295 add_setshow_enum_cmd ("displaced-stepping", class_run
,
7296 can_use_displaced_stepping_enum
,
7297 &can_use_displaced_stepping
, _("\
7298 Set debugger's willingness to use displaced stepping."), _("\
7299 Show debugger's willingness to use displaced stepping."), _("\
7300 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7301 supported by the target architecture. If off, gdb will not use displaced\n\
7302 stepping to step over breakpoints, even if such is supported by the target\n\
7303 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7304 if the target architecture supports it and non-stop mode is active, but will not\n\
7305 use it in all-stop mode (see help set non-stop)."),
7307 show_can_use_displaced_stepping
,
7308 &setlist
, &showlist
);
7310 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7311 &exec_direction
, _("Set direction of execution.\n\
7312 Options are 'forward' or 'reverse'."),
7313 _("Show direction of execution (forward/reverse)."),
7314 _("Tells gdb whether to execute forward or backward."),
7315 set_exec_direction_func
, show_exec_direction_func
,
7316 &setlist
, &showlist
);
7318 /* Set/show detach-on-fork: user-settable mode. */
7320 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7321 Set whether gdb will detach the child of a fork."), _("\
7322 Show whether gdb will detach the child of a fork."), _("\
7323 Tells gdb whether to detach the child of a fork."),
7324 NULL
, NULL
, &setlist
, &showlist
);
7326 /* Set/show disable address space randomization mode. */
7328 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7329 &disable_randomization
, _("\
7330 Set disabling of debuggee's virtual address space randomization."), _("\
7331 Show disabling of debuggee's virtual address space randomization."), _("\
7332 When this mode is on (which is the default), randomization of the virtual\n\
7333 address space is disabled. Standalone programs run with the randomization\n\
7334 enabled by default on some platforms."),
7335 &set_disable_randomization
,
7336 &show_disable_randomization
,
7337 &setlist
, &showlist
);
7339 /* ptid initializations */
7340 inferior_ptid
= null_ptid
;
7341 target_last_wait_ptid
= minus_one_ptid
;
7343 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7344 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7345 observer_attach_thread_exit (infrun_thread_thread_exit
);
7346 observer_attach_inferior_exit (infrun_inferior_exit
);
7348 /* Explicitly create without lookup, since that tries to create a
7349 value with a void typed value, and when we get here, gdbarch
7350 isn't initialized yet. At this point, we're quite sure there
7351 isn't another convenience variable of the same name. */
7352 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7354 add_setshow_boolean_cmd ("observer", no_class
,
7355 &observer_mode_1
, _("\
7356 Set whether gdb controls the inferior in observer mode."), _("\
7357 Show whether gdb controls the inferior in observer mode."), _("\
7358 In observer mode, GDB can get data from the inferior, but not\n\
7359 affect its execution. Registers and memory may not be changed,\n\
7360 breakpoints may not be set, and the program cannot be interrupted\n\