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
;
2396 int new_thread_event
;
2400 static void handle_inferior_event (struct execution_control_state
*ecs
);
2402 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2403 struct execution_control_state
*ecs
);
2404 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2405 struct execution_control_state
*ecs
);
2406 static void check_exception_resume (struct execution_control_state
*,
2407 struct frame_info
*);
2409 static void stop_stepping (struct execution_control_state
*ecs
);
2410 static void prepare_to_wait (struct execution_control_state
*ecs
);
2411 static void keep_going (struct execution_control_state
*ecs
);
2413 /* Callback for iterate over threads. If the thread is stopped, but
2414 the user/frontend doesn't know about that yet, go through
2415 normal_stop, as if the thread had just stopped now. ARG points at
2416 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2417 ptid_is_pid(PTID) is true, applies to all threads of the process
2418 pointed at by PTID. Otherwise, apply only to the thread pointed by
2422 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2424 ptid_t ptid
= * (ptid_t
*) arg
;
2426 if ((ptid_equal (info
->ptid
, ptid
)
2427 || ptid_equal (minus_one_ptid
, ptid
)
2428 || (ptid_is_pid (ptid
)
2429 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2430 && is_running (info
->ptid
)
2431 && !is_executing (info
->ptid
))
2433 struct cleanup
*old_chain
;
2434 struct execution_control_state ecss
;
2435 struct execution_control_state
*ecs
= &ecss
;
2437 memset (ecs
, 0, sizeof (*ecs
));
2439 old_chain
= make_cleanup_restore_current_thread ();
2441 switch_to_thread (info
->ptid
);
2443 /* Go through handle_inferior_event/normal_stop, so we always
2444 have consistent output as if the stop event had been
2446 ecs
->ptid
= info
->ptid
;
2447 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2448 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2449 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
2451 handle_inferior_event (ecs
);
2453 if (!ecs
->wait_some_more
)
2455 struct thread_info
*tp
;
2459 /* Finish off the continuations. */
2460 tp
= inferior_thread ();
2461 do_all_intermediate_continuations_thread (tp
, 1);
2462 do_all_continuations_thread (tp
, 1);
2465 do_cleanups (old_chain
);
2471 /* This function is attached as a "thread_stop_requested" observer.
2472 Cleanup local state that assumed the PTID was to be resumed, and
2473 report the stop to the frontend. */
2476 infrun_thread_stop_requested (ptid_t ptid
)
2478 struct displaced_step_inferior_state
*displaced
;
2480 /* PTID was requested to stop. Remove it from the displaced
2481 stepping queue, so we don't try to resume it automatically. */
2483 for (displaced
= displaced_step_inferior_states
;
2485 displaced
= displaced
->next
)
2487 struct displaced_step_request
*it
, **prev_next_p
;
2489 it
= displaced
->step_request_queue
;
2490 prev_next_p
= &displaced
->step_request_queue
;
2493 if (ptid_match (it
->ptid
, ptid
))
2495 *prev_next_p
= it
->next
;
2501 prev_next_p
= &it
->next
;
2508 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2512 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2514 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2515 nullify_last_target_wait_ptid ();
2518 /* Callback for iterate_over_threads. */
2521 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
2523 if (is_exited (info
->ptid
))
2526 delete_step_resume_breakpoint (info
);
2527 delete_exception_resume_breakpoint (info
);
2531 /* In all-stop, delete the step resume breakpoint of any thread that
2532 had one. In non-stop, delete the step resume breakpoint of the
2533 thread that just stopped. */
2536 delete_step_thread_step_resume_breakpoint (void)
2538 if (!target_has_execution
2539 || ptid_equal (inferior_ptid
, null_ptid
))
2540 /* If the inferior has exited, we have already deleted the step
2541 resume breakpoints out of GDB's lists. */
2546 /* If in non-stop mode, only delete the step-resume or
2547 longjmp-resume breakpoint of the thread that just stopped
2549 struct thread_info
*tp
= inferior_thread ();
2551 delete_step_resume_breakpoint (tp
);
2552 delete_exception_resume_breakpoint (tp
);
2555 /* In all-stop mode, delete all step-resume and longjmp-resume
2556 breakpoints of any thread that had them. */
2557 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
2560 /* A cleanup wrapper. */
2563 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
2565 delete_step_thread_step_resume_breakpoint ();
2568 /* Pretty print the results of target_wait, for debugging purposes. */
2571 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
2572 const struct target_waitstatus
*ws
)
2574 char *status_string
= target_waitstatus_to_string (ws
);
2575 struct ui_file
*tmp_stream
= mem_fileopen ();
2578 /* The text is split over several lines because it was getting too long.
2579 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2580 output as a unit; we want only one timestamp printed if debug_timestamp
2583 fprintf_unfiltered (tmp_stream
,
2584 "infrun: target_wait (%d", PIDGET (waiton_ptid
));
2585 if (PIDGET (waiton_ptid
) != -1)
2586 fprintf_unfiltered (tmp_stream
,
2587 " [%s]", target_pid_to_str (waiton_ptid
));
2588 fprintf_unfiltered (tmp_stream
, ", status) =\n");
2589 fprintf_unfiltered (tmp_stream
,
2590 "infrun: %d [%s],\n",
2591 PIDGET (result_ptid
), target_pid_to_str (result_ptid
));
2592 fprintf_unfiltered (tmp_stream
,
2596 text
= ui_file_xstrdup (tmp_stream
, NULL
);
2598 /* This uses %s in part to handle %'s in the text, but also to avoid
2599 a gcc error: the format attribute requires a string literal. */
2600 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
2602 xfree (status_string
);
2604 ui_file_delete (tmp_stream
);
2607 /* Prepare and stabilize the inferior for detaching it. E.g.,
2608 detaching while a thread is displaced stepping is a recipe for
2609 crashing it, as nothing would readjust the PC out of the scratch
2613 prepare_for_detach (void)
2615 struct inferior
*inf
= current_inferior ();
2616 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
2617 struct cleanup
*old_chain_1
;
2618 struct displaced_step_inferior_state
*displaced
;
2620 displaced
= get_displaced_stepping_state (inf
->pid
);
2622 /* Is any thread of this process displaced stepping? If not,
2623 there's nothing else to do. */
2624 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
2628 fprintf_unfiltered (gdb_stdlog
,
2629 "displaced-stepping in-process while detaching");
2631 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
2634 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
2636 struct cleanup
*old_chain_2
;
2637 struct execution_control_state ecss
;
2638 struct execution_control_state
*ecs
;
2641 memset (ecs
, 0, sizeof (*ecs
));
2643 overlay_cache_invalid
= 1;
2645 if (deprecated_target_wait_hook
)
2646 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
2648 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
2651 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
2653 /* If an error happens while handling the event, propagate GDB's
2654 knowledge of the executing state to the frontend/user running
2656 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
2659 /* In non-stop mode, each thread is handled individually.
2660 Switch early, so the global state is set correctly for this
2663 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2664 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2665 context_switch (ecs
->ptid
);
2667 /* Now figure out what to do with the result of the result. */
2668 handle_inferior_event (ecs
);
2670 /* No error, don't finish the state yet. */
2671 discard_cleanups (old_chain_2
);
2673 /* Breakpoints and watchpoints are not installed on the target
2674 at this point, and signals are passed directly to the
2675 inferior, so this must mean the process is gone. */
2676 if (!ecs
->wait_some_more
)
2678 discard_cleanups (old_chain_1
);
2679 error (_("Program exited while detaching"));
2683 discard_cleanups (old_chain_1
);
2686 /* Wait for control to return from inferior to debugger.
2688 If inferior gets a signal, we may decide to start it up again
2689 instead of returning. That is why there is a loop in this function.
2690 When this function actually returns it means the inferior
2691 should be left stopped and GDB should read more commands. */
2694 wait_for_inferior (void)
2696 struct cleanup
*old_cleanups
;
2700 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
2703 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
2707 struct execution_control_state ecss
;
2708 struct execution_control_state
*ecs
= &ecss
;
2709 struct cleanup
*old_chain
;
2711 memset (ecs
, 0, sizeof (*ecs
));
2713 overlay_cache_invalid
= 1;
2715 if (deprecated_target_wait_hook
)
2716 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
2718 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
2721 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2723 /* If an error happens while handling the event, propagate GDB's
2724 knowledge of the executing state to the frontend/user running
2726 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2728 /* Now figure out what to do with the result of the result. */
2729 handle_inferior_event (ecs
);
2731 /* No error, don't finish the state yet. */
2732 discard_cleanups (old_chain
);
2734 if (!ecs
->wait_some_more
)
2738 do_cleanups (old_cleanups
);
2741 /* Asynchronous version of wait_for_inferior. It is called by the
2742 event loop whenever a change of state is detected on the file
2743 descriptor corresponding to the target. It can be called more than
2744 once to complete a single execution command. In such cases we need
2745 to keep the state in a global variable ECSS. If it is the last time
2746 that this function is called for a single execution command, then
2747 report to the user that the inferior has stopped, and do the
2748 necessary cleanups. */
2751 fetch_inferior_event (void *client_data
)
2753 struct execution_control_state ecss
;
2754 struct execution_control_state
*ecs
= &ecss
;
2755 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
2756 struct cleanup
*ts_old_chain
;
2757 int was_sync
= sync_execution
;
2760 memset (ecs
, 0, sizeof (*ecs
));
2762 /* We're handling a live event, so make sure we're doing live
2763 debugging. If we're looking at traceframes while the target is
2764 running, we're going to need to get back to that mode after
2765 handling the event. */
2768 make_cleanup_restore_current_traceframe ();
2769 set_current_traceframe (-1);
2773 /* In non-stop mode, the user/frontend should not notice a thread
2774 switch due to internal events. Make sure we reverse to the
2775 user selected thread and frame after handling the event and
2776 running any breakpoint commands. */
2777 make_cleanup_restore_current_thread ();
2779 overlay_cache_invalid
= 1;
2781 make_cleanup_restore_integer (&execution_direction
);
2782 execution_direction
= target_execution_direction ();
2784 if (deprecated_target_wait_hook
)
2786 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2788 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2791 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2794 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
2795 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
2796 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2797 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2798 /* In non-stop mode, each thread is handled individually. Switch
2799 early, so the global state is set correctly for this
2801 context_switch (ecs
->ptid
);
2803 /* If an error happens while handling the event, propagate GDB's
2804 knowledge of the executing state to the frontend/user running
2807 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2809 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
2811 /* Get executed before make_cleanup_restore_current_thread above to apply
2812 still for the thread which has thrown the exception. */
2813 make_bpstat_clear_actions_cleanup ();
2815 /* Now figure out what to do with the result of the result. */
2816 handle_inferior_event (ecs
);
2818 if (!ecs
->wait_some_more
)
2820 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2822 delete_step_thread_step_resume_breakpoint ();
2824 /* We may not find an inferior if this was a process exit. */
2825 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
2828 if (target_has_execution
2829 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
2830 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2831 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2832 && ecs
->event_thread
->step_multi
2833 && ecs
->event_thread
->control
.stop_step
)
2834 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
2837 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2842 /* No error, don't finish the thread states yet. */
2843 discard_cleanups (ts_old_chain
);
2845 /* Revert thread and frame. */
2846 do_cleanups (old_chain
);
2848 /* If the inferior was in sync execution mode, and now isn't,
2849 restore the prompt (a synchronous execution command has finished,
2850 and we're ready for input). */
2851 if (interpreter_async
&& was_sync
&& !sync_execution
)
2852 display_gdb_prompt (0);
2856 && exec_done_display_p
2857 && (ptid_equal (inferior_ptid
, null_ptid
)
2858 || !is_running (inferior_ptid
)))
2859 printf_unfiltered (_("completed.\n"));
2862 /* Record the frame and location we're currently stepping through. */
2864 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
2866 struct thread_info
*tp
= inferior_thread ();
2868 tp
->control
.step_frame_id
= get_frame_id (frame
);
2869 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
2871 tp
->current_symtab
= sal
.symtab
;
2872 tp
->current_line
= sal
.line
;
2875 /* Clear context switchable stepping state. */
2878 init_thread_stepping_state (struct thread_info
*tss
)
2880 tss
->stepping_over_breakpoint
= 0;
2881 tss
->step_after_step_resume_breakpoint
= 0;
2884 /* Return the cached copy of the last pid/waitstatus returned by
2885 target_wait()/deprecated_target_wait_hook(). The data is actually
2886 cached by handle_inferior_event(), which gets called immediately
2887 after target_wait()/deprecated_target_wait_hook(). */
2890 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
2892 *ptidp
= target_last_wait_ptid
;
2893 *status
= target_last_waitstatus
;
2897 nullify_last_target_wait_ptid (void)
2899 target_last_wait_ptid
= minus_one_ptid
;
2902 /* Switch thread contexts. */
2905 context_switch (ptid_t ptid
)
2907 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
2909 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
2910 target_pid_to_str (inferior_ptid
));
2911 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
2912 target_pid_to_str (ptid
));
2915 switch_to_thread (ptid
);
2919 adjust_pc_after_break (struct execution_control_state
*ecs
)
2921 struct regcache
*regcache
;
2922 struct gdbarch
*gdbarch
;
2923 struct address_space
*aspace
;
2924 CORE_ADDR breakpoint_pc
;
2926 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2927 we aren't, just return.
2929 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2930 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2931 implemented by software breakpoints should be handled through the normal
2934 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2935 different signals (SIGILL or SIGEMT for instance), but it is less
2936 clear where the PC is pointing afterwards. It may not match
2937 gdbarch_decr_pc_after_break. I don't know any specific target that
2938 generates these signals at breakpoints (the code has been in GDB since at
2939 least 1992) so I can not guess how to handle them here.
2941 In earlier versions of GDB, a target with
2942 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2943 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2944 target with both of these set in GDB history, and it seems unlikely to be
2945 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2947 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
2950 if (ecs
->ws
.value
.sig
!= GDB_SIGNAL_TRAP
)
2953 /* In reverse execution, when a breakpoint is hit, the instruction
2954 under it has already been de-executed. The reported PC always
2955 points at the breakpoint address, so adjusting it further would
2956 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2959 B1 0x08000000 : INSN1
2960 B2 0x08000001 : INSN2
2962 PC -> 0x08000003 : INSN4
2964 Say you're stopped at 0x08000003 as above. Reverse continuing
2965 from that point should hit B2 as below. Reading the PC when the
2966 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2967 been de-executed already.
2969 B1 0x08000000 : INSN1
2970 B2 PC -> 0x08000001 : INSN2
2974 We can't apply the same logic as for forward execution, because
2975 we would wrongly adjust the PC to 0x08000000, since there's a
2976 breakpoint at PC - 1. We'd then report a hit on B1, although
2977 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2979 if (execution_direction
== EXEC_REVERSE
)
2982 /* If this target does not decrement the PC after breakpoints, then
2983 we have nothing to do. */
2984 regcache
= get_thread_regcache (ecs
->ptid
);
2985 gdbarch
= get_regcache_arch (regcache
);
2986 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
2989 aspace
= get_regcache_aspace (regcache
);
2991 /* Find the location where (if we've hit a breakpoint) the
2992 breakpoint would be. */
2993 breakpoint_pc
= regcache_read_pc (regcache
)
2994 - gdbarch_decr_pc_after_break (gdbarch
);
2996 /* Check whether there actually is a software breakpoint inserted at
2999 If in non-stop mode, a race condition is possible where we've
3000 removed a breakpoint, but stop events for that breakpoint were
3001 already queued and arrive later. To suppress those spurious
3002 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3003 and retire them after a number of stop events are reported. */
3004 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3005 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3007 struct cleanup
*old_cleanups
= NULL
;
3010 old_cleanups
= record_gdb_operation_disable_set ();
3012 /* When using hardware single-step, a SIGTRAP is reported for both
3013 a completed single-step and a software breakpoint. Need to
3014 differentiate between the two, as the latter needs adjusting
3015 but the former does not.
3017 The SIGTRAP can be due to a completed hardware single-step only if
3018 - we didn't insert software single-step breakpoints
3019 - the thread to be examined is still the current thread
3020 - this thread is currently being stepped
3022 If any of these events did not occur, we must have stopped due
3023 to hitting a software breakpoint, and have to back up to the
3026 As a special case, we could have hardware single-stepped a
3027 software breakpoint. In this case (prev_pc == breakpoint_pc),
3028 we also need to back up to the breakpoint address. */
3030 if (singlestep_breakpoints_inserted_p
3031 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
3032 || !currently_stepping (ecs
->event_thread
)
3033 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
3034 regcache_write_pc (regcache
, breakpoint_pc
);
3037 do_cleanups (old_cleanups
);
3042 init_infwait_state (void)
3044 waiton_ptid
= pid_to_ptid (-1);
3045 infwait_state
= infwait_normal_state
;
3049 error_is_running (void)
3051 error (_("Cannot execute this command while "
3052 "the selected thread is running."));
3056 ensure_not_running (void)
3058 if (is_running (inferior_ptid
))
3059 error_is_running ();
3063 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3065 for (frame
= get_prev_frame (frame
);
3067 frame
= get_prev_frame (frame
))
3069 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3071 if (get_frame_type (frame
) != INLINE_FRAME
)
3078 /* Auxiliary function that handles syscall entry/return events.
3079 It returns 1 if the inferior should keep going (and GDB
3080 should ignore the event), or 0 if the event deserves to be
3084 handle_syscall_event (struct execution_control_state
*ecs
)
3086 struct regcache
*regcache
;
3087 struct gdbarch
*gdbarch
;
3090 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3091 context_switch (ecs
->ptid
);
3093 regcache
= get_thread_regcache (ecs
->ptid
);
3094 gdbarch
= get_regcache_arch (regcache
);
3095 syscall_number
= ecs
->ws
.value
.syscall_number
;
3096 stop_pc
= regcache_read_pc (regcache
);
3098 if (catch_syscall_enabled () > 0
3099 && catching_syscall_number (syscall_number
) > 0)
3102 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3105 ecs
->event_thread
->control
.stop_bpstat
3106 = bpstat_stop_status (get_regcache_aspace (regcache
),
3107 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3109 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3111 if (!ecs
->random_signal
)
3113 /* Catchpoint hit. */
3114 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3119 /* If no catchpoint triggered for this, then keep going. */
3120 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3125 /* Clear the supplied execution_control_state's stop_func_* fields. */
3128 clear_stop_func (struct execution_control_state
*ecs
)
3130 ecs
->stop_func_filled_in
= 0;
3131 ecs
->stop_func_start
= 0;
3132 ecs
->stop_func_end
= 0;
3133 ecs
->stop_func_name
= NULL
;
3136 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3139 fill_in_stop_func (struct gdbarch
*gdbarch
,
3140 struct execution_control_state
*ecs
)
3142 if (!ecs
->stop_func_filled_in
)
3144 /* Don't care about return value; stop_func_start and stop_func_name
3145 will both be 0 if it doesn't work. */
3146 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3147 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3148 ecs
->stop_func_start
3149 += gdbarch_deprecated_function_start_offset (gdbarch
);
3151 ecs
->stop_func_filled_in
= 1;
3155 /* Given an execution control state that has been freshly filled in
3156 by an event from the inferior, figure out what it means and take
3157 appropriate action. */
3160 handle_inferior_event (struct execution_control_state
*ecs
)
3162 struct frame_info
*frame
;
3163 struct gdbarch
*gdbarch
;
3164 int stopped_by_watchpoint
;
3165 int stepped_after_stopped_by_watchpoint
= 0;
3166 struct symtab_and_line stop_pc_sal
;
3167 enum stop_kind stop_soon
;
3169 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3171 /* We had an event in the inferior, but we are not interested in
3172 handling it at this level. The lower layers have already
3173 done what needs to be done, if anything.
3175 One of the possible circumstances for this is when the
3176 inferior produces output for the console. The inferior has
3177 not stopped, and we are ignoring the event. Another possible
3178 circumstance is any event which the lower level knows will be
3179 reported multiple times without an intervening resume. */
3181 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3182 prepare_to_wait (ecs
);
3186 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3187 && target_can_async_p () && !sync_execution
)
3189 /* There were no unwaited-for children left in the target, but,
3190 we're not synchronously waiting for events either. Just
3191 ignore. Otherwise, if we were running a synchronous
3192 execution command, we need to cancel it and give the user
3193 back the terminal. */
3195 fprintf_unfiltered (gdb_stdlog
,
3196 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3197 prepare_to_wait (ecs
);
3201 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3202 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3203 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
3205 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3208 stop_soon
= inf
->control
.stop_soon
;
3211 stop_soon
= NO_STOP_QUIETLY
;
3213 /* Cache the last pid/waitstatus. */
3214 target_last_wait_ptid
= ecs
->ptid
;
3215 target_last_waitstatus
= ecs
->ws
;
3217 /* Always clear state belonging to the previous time we stopped. */
3218 stop_stack_dummy
= STOP_NONE
;
3220 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3222 /* No unwaited-for children left. IOW, all resumed children
3225 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3227 stop_print_frame
= 0;
3228 stop_stepping (ecs
);
3232 /* If it's a new process, add it to the thread database. */
3234 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
3235 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
3236 && !in_thread_list (ecs
->ptid
));
3238 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3239 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
3240 add_thread (ecs
->ptid
);
3242 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3244 /* Dependent on valid ECS->EVENT_THREAD. */
3245 adjust_pc_after_break (ecs
);
3247 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3248 reinit_frame_cache ();
3250 breakpoint_retire_moribund ();
3252 /* First, distinguish signals caused by the debugger from signals
3253 that have to do with the program's own actions. Note that
3254 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3255 on the operating system version. Here we detect when a SIGILL or
3256 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3257 something similar for SIGSEGV, since a SIGSEGV will be generated
3258 when we're trying to execute a breakpoint instruction on a
3259 non-executable stack. This happens for call dummy breakpoints
3260 for architectures like SPARC that place call dummies on the
3262 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3263 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3264 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3265 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3267 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3269 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3270 regcache_read_pc (regcache
)))
3273 fprintf_unfiltered (gdb_stdlog
,
3274 "infrun: Treating signal as SIGTRAP\n");
3275 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3279 /* Mark the non-executing threads accordingly. In all-stop, all
3280 threads of all processes are stopped when we get any event
3281 reported. In non-stop mode, only the event thread stops. If
3282 we're handling a process exit in non-stop mode, there's nothing
3283 to do, as threads of the dead process are gone, and threads of
3284 any other process were left running. */
3286 set_executing (minus_one_ptid
, 0);
3287 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3288 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3289 set_executing (ecs
->ptid
, 0);
3291 switch (infwait_state
)
3293 case infwait_thread_hop_state
:
3295 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
3298 case infwait_normal_state
:
3300 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
3303 case infwait_step_watch_state
:
3305 fprintf_unfiltered (gdb_stdlog
,
3306 "infrun: infwait_step_watch_state\n");
3308 stepped_after_stopped_by_watchpoint
= 1;
3311 case infwait_nonstep_watch_state
:
3313 fprintf_unfiltered (gdb_stdlog
,
3314 "infrun: infwait_nonstep_watch_state\n");
3315 insert_breakpoints ();
3317 /* FIXME-maybe: is this cleaner than setting a flag? Does it
3318 handle things like signals arriving and other things happening
3319 in combination correctly? */
3320 stepped_after_stopped_by_watchpoint
= 1;
3324 internal_error (__FILE__
, __LINE__
, _("bad switch"));
3327 infwait_state
= infwait_normal_state
;
3328 waiton_ptid
= pid_to_ptid (-1);
3330 switch (ecs
->ws
.kind
)
3332 case TARGET_WAITKIND_LOADED
:
3334 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3335 /* Ignore gracefully during startup of the inferior, as it might
3336 be the shell which has just loaded some objects, otherwise
3337 add the symbols for the newly loaded objects. Also ignore at
3338 the beginning of an attach or remote session; we will query
3339 the full list of libraries once the connection is
3341 if (stop_soon
== NO_STOP_QUIETLY
)
3343 struct regcache
*regcache
;
3345 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3346 context_switch (ecs
->ptid
);
3347 regcache
= get_thread_regcache (ecs
->ptid
);
3349 handle_solib_event ();
3351 ecs
->event_thread
->control
.stop_bpstat
3352 = bpstat_stop_status (get_regcache_aspace (regcache
),
3353 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3355 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3357 if (!ecs
->random_signal
)
3359 /* A catchpoint triggered. */
3360 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3361 goto process_event_stop_test
;
3364 /* If requested, stop when the dynamic linker notifies
3365 gdb of events. This allows the user to get control
3366 and place breakpoints in initializer routines for
3367 dynamically loaded objects (among other things). */
3368 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3369 if (stop_on_solib_events
)
3371 /* Make sure we print "Stopped due to solib-event" in
3373 stop_print_frame
= 1;
3375 stop_stepping (ecs
);
3380 /* If we are skipping through a shell, or through shared library
3381 loading that we aren't interested in, resume the program. If
3382 we're running the program normally, also resume. But stop if
3383 we're attaching or setting up a remote connection. */
3384 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3386 /* Loading of shared libraries might have changed breakpoint
3387 addresses. Make sure new breakpoints are inserted. */
3388 if (stop_soon
== NO_STOP_QUIETLY
3389 && !breakpoints_always_inserted_mode ())
3390 insert_breakpoints ();
3391 resume (0, GDB_SIGNAL_0
);
3392 prepare_to_wait (ecs
);
3398 case TARGET_WAITKIND_SPURIOUS
:
3400 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3401 resume (0, GDB_SIGNAL_0
);
3402 prepare_to_wait (ecs
);
3405 case TARGET_WAITKIND_EXITED
:
3407 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
3408 inferior_ptid
= ecs
->ptid
;
3409 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3410 set_current_program_space (current_inferior ()->pspace
);
3411 handle_vfork_child_exec_or_exit (0);
3412 target_terminal_ours (); /* Must do this before mourn anyway. */
3413 print_exited_reason (ecs
->ws
.value
.integer
);
3415 /* Record the exit code in the convenience variable $_exitcode, so
3416 that the user can inspect this again later. */
3417 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3418 (LONGEST
) ecs
->ws
.value
.integer
);
3420 /* Also record this in the inferior itself. */
3421 current_inferior ()->has_exit_code
= 1;
3422 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3424 gdb_flush (gdb_stdout
);
3425 target_mourn_inferior ();
3426 singlestep_breakpoints_inserted_p
= 0;
3427 cancel_single_step_breakpoints ();
3428 stop_print_frame
= 0;
3429 stop_stepping (ecs
);
3432 case TARGET_WAITKIND_SIGNALLED
:
3434 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
3435 inferior_ptid
= ecs
->ptid
;
3436 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3437 set_current_program_space (current_inferior ()->pspace
);
3438 handle_vfork_child_exec_or_exit (0);
3439 stop_print_frame
= 0;
3440 target_terminal_ours (); /* Must do this before mourn anyway. */
3442 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
3443 reach here unless the inferior is dead. However, for years
3444 target_kill() was called here, which hints that fatal signals aren't
3445 really fatal on some systems. If that's true, then some changes
3447 target_mourn_inferior ();
3449 print_signal_exited_reason (ecs
->ws
.value
.sig
);
3450 singlestep_breakpoints_inserted_p
= 0;
3451 cancel_single_step_breakpoints ();
3452 stop_stepping (ecs
);
3455 /* The following are the only cases in which we keep going;
3456 the above cases end in a continue or goto. */
3457 case TARGET_WAITKIND_FORKED
:
3458 case TARGET_WAITKIND_VFORKED
:
3460 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3462 /* Check whether the inferior is displaced stepping. */
3464 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3465 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3466 struct displaced_step_inferior_state
*displaced
3467 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3469 /* If checking displaced stepping is supported, and thread
3470 ecs->ptid is displaced stepping. */
3471 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3473 struct inferior
*parent_inf
3474 = find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3475 struct regcache
*child_regcache
;
3476 CORE_ADDR parent_pc
;
3478 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3479 indicating that the displaced stepping of syscall instruction
3480 has been done. Perform cleanup for parent process here. Note
3481 that this operation also cleans up the child process for vfork,
3482 because their pages are shared. */
3483 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
3485 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3487 /* Restore scratch pad for child process. */
3488 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3491 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3492 the child's PC is also within the scratchpad. Set the child's PC
3493 to the parent's PC value, which has already been fixed up.
3494 FIXME: we use the parent's aspace here, although we're touching
3495 the child, because the child hasn't been added to the inferior
3496 list yet at this point. */
3499 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3501 parent_inf
->aspace
);
3502 /* Read PC value of parent process. */
3503 parent_pc
= regcache_read_pc (regcache
);
3505 if (debug_displaced
)
3506 fprintf_unfiltered (gdb_stdlog
,
3507 "displaced: write child pc from %s to %s\n",
3509 regcache_read_pc (child_regcache
)),
3510 paddress (gdbarch
, parent_pc
));
3512 regcache_write_pc (child_regcache
, parent_pc
);
3516 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3518 context_switch (ecs
->ptid
);
3519 reinit_frame_cache ();
3522 /* Immediately detach breakpoints from the child before there's
3523 any chance of letting the user delete breakpoints from the
3524 breakpoint lists. If we don't do this early, it's easy to
3525 leave left over traps in the child, vis: "break foo; catch
3526 fork; c; <fork>; del; c; <child calls foo>". We only follow
3527 the fork on the last `continue', and by that time the
3528 breakpoint at "foo" is long gone from the breakpoint table.
3529 If we vforked, then we don't need to unpatch here, since both
3530 parent and child are sharing the same memory pages; we'll
3531 need to unpatch at follow/detach time instead to be certain
3532 that new breakpoints added between catchpoint hit time and
3533 vfork follow are detached. */
3534 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3536 int child_pid
= ptid_get_pid (ecs
->ws
.value
.related_pid
);
3538 /* This won't actually modify the breakpoint list, but will
3539 physically remove the breakpoints from the child. */
3540 detach_breakpoints (child_pid
);
3543 if (singlestep_breakpoints_inserted_p
)
3545 /* Pull the single step breakpoints out of the target. */
3546 remove_single_step_breakpoints ();
3547 singlestep_breakpoints_inserted_p
= 0;
3550 /* In case the event is caught by a catchpoint, remember that
3551 the event is to be followed at the next resume of the thread,
3552 and not immediately. */
3553 ecs
->event_thread
->pending_follow
= ecs
->ws
;
3555 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3557 ecs
->event_thread
->control
.stop_bpstat
3558 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3559 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3561 /* Note that we're interested in knowing the bpstat actually
3562 causes a stop, not just if it may explain the signal.
3563 Software watchpoints, for example, always appear in the
3566 = !bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
);
3568 /* If no catchpoint triggered for this, then keep going. */
3569 if (ecs
->random_signal
)
3575 = (follow_fork_mode_string
== follow_fork_mode_child
);
3577 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3579 should_resume
= follow_fork ();
3582 child
= ecs
->ws
.value
.related_pid
;
3584 /* In non-stop mode, also resume the other branch. */
3585 if (non_stop
&& !detach_fork
)
3588 switch_to_thread (parent
);
3590 switch_to_thread (child
);
3592 ecs
->event_thread
= inferior_thread ();
3593 ecs
->ptid
= inferior_ptid
;
3598 switch_to_thread (child
);
3600 switch_to_thread (parent
);
3602 ecs
->event_thread
= inferior_thread ();
3603 ecs
->ptid
= inferior_ptid
;
3608 stop_stepping (ecs
);
3611 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3612 goto process_event_stop_test
;
3614 case TARGET_WAITKIND_VFORK_DONE
:
3615 /* Done with the shared memory region. Re-insert breakpoints in
3616 the parent, and keep going. */
3619 fprintf_unfiltered (gdb_stdlog
,
3620 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3622 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3623 context_switch (ecs
->ptid
);
3625 current_inferior ()->waiting_for_vfork_done
= 0;
3626 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
3627 /* This also takes care of reinserting breakpoints in the
3628 previously locked inferior. */
3632 case TARGET_WAITKIND_EXECD
:
3634 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
3636 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3638 context_switch (ecs
->ptid
);
3639 reinit_frame_cache ();
3642 singlestep_breakpoints_inserted_p
= 0;
3643 cancel_single_step_breakpoints ();
3645 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3647 /* Do whatever is necessary to the parent branch of the vfork. */
3648 handle_vfork_child_exec_or_exit (1);
3650 /* This causes the eventpoints and symbol table to be reset.
3651 Must do this now, before trying to determine whether to
3653 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
3655 ecs
->event_thread
->control
.stop_bpstat
3656 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3657 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3659 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3661 /* Note that this may be referenced from inside
3662 bpstat_stop_status above, through inferior_has_execd. */
3663 xfree (ecs
->ws
.value
.execd_pathname
);
3664 ecs
->ws
.value
.execd_pathname
= NULL
;
3666 /* If no catchpoint triggered for this, then keep going. */
3667 if (ecs
->random_signal
)
3669 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3673 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
3674 goto process_event_stop_test
;
3676 /* Be careful not to try to gather much state about a thread
3677 that's in a syscall. It's frequently a losing proposition. */
3678 case TARGET_WAITKIND_SYSCALL_ENTRY
:
3680 fprintf_unfiltered (gdb_stdlog
,
3681 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3682 /* Getting the current syscall number. */
3683 if (handle_syscall_event (ecs
) != 0)
3685 goto process_event_stop_test
;
3687 /* Before examining the threads further, step this thread to
3688 get it entirely out of the syscall. (We get notice of the
3689 event when the thread is just on the verge of exiting a
3690 syscall. Stepping one instruction seems to get it back
3692 case TARGET_WAITKIND_SYSCALL_RETURN
:
3694 fprintf_unfiltered (gdb_stdlog
,
3695 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3696 if (handle_syscall_event (ecs
) != 0)
3698 goto process_event_stop_test
;
3700 case TARGET_WAITKIND_STOPPED
:
3702 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
3703 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
3706 case TARGET_WAITKIND_NO_HISTORY
:
3708 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
3709 /* Reverse execution: target ran out of history info. */
3710 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3711 print_no_history_reason ();
3712 stop_stepping (ecs
);
3716 if (ecs
->new_thread_event
)
3719 /* Non-stop assumes that the target handles adding new threads
3720 to the thread list. */
3721 internal_error (__FILE__
, __LINE__
,
3722 "targets should add new threads to the thread "
3723 "list themselves in non-stop mode.");
3725 /* We may want to consider not doing a resume here in order to
3726 give the user a chance to play with the new thread. It might
3727 be good to make that a user-settable option. */
3729 /* At this point, all threads are stopped (happens automatically
3730 in either the OS or the native code). Therefore we need to
3731 continue all threads in order to make progress. */
3733 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3734 context_switch (ecs
->ptid
);
3735 target_resume (RESUME_ALL
, 0, GDB_SIGNAL_0
);
3736 prepare_to_wait (ecs
);
3740 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
3742 /* Do we need to clean up the state of a thread that has
3743 completed a displaced single-step? (Doing so usually affects
3744 the PC, so do it here, before we set stop_pc.) */
3745 displaced_step_fixup (ecs
->ptid
,
3746 ecs
->event_thread
->suspend
.stop_signal
);
3748 /* If we either finished a single-step or hit a breakpoint, but
3749 the user wanted this thread to be stopped, pretend we got a
3750 SIG0 (generic unsignaled stop). */
3752 if (ecs
->event_thread
->stop_requested
3753 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3754 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3757 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3761 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3762 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3763 struct cleanup
*old_chain
= save_inferior_ptid ();
3765 inferior_ptid
= ecs
->ptid
;
3767 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
3768 paddress (gdbarch
, stop_pc
));
3769 if (target_stopped_by_watchpoint ())
3773 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
3775 if (target_stopped_data_address (¤t_target
, &addr
))
3776 fprintf_unfiltered (gdb_stdlog
,
3777 "infrun: stopped data address = %s\n",
3778 paddress (gdbarch
, addr
));
3780 fprintf_unfiltered (gdb_stdlog
,
3781 "infrun: (no data address available)\n");
3784 do_cleanups (old_chain
);
3787 if (stepping_past_singlestep_breakpoint
)
3789 gdb_assert (singlestep_breakpoints_inserted_p
);
3790 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
3791 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
3793 stepping_past_singlestep_breakpoint
= 0;
3795 /* We've either finished single-stepping past the single-step
3796 breakpoint, or stopped for some other reason. It would be nice if
3797 we could tell, but we can't reliably. */
3798 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3801 fprintf_unfiltered (gdb_stdlog
,
3802 "infrun: stepping_past_"
3803 "singlestep_breakpoint\n");
3804 /* Pull the single step breakpoints out of the target. */
3805 remove_single_step_breakpoints ();
3806 singlestep_breakpoints_inserted_p
= 0;
3808 ecs
->random_signal
= 0;
3809 ecs
->event_thread
->control
.trap_expected
= 0;
3811 context_switch (saved_singlestep_ptid
);
3812 if (deprecated_context_hook
)
3813 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3815 resume (1, GDB_SIGNAL_0
);
3816 prepare_to_wait (ecs
);
3821 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
3823 /* In non-stop mode, there's never a deferred_step_ptid set. */
3824 gdb_assert (!non_stop
);
3826 /* If we stopped for some other reason than single-stepping, ignore
3827 the fact that we were supposed to switch back. */
3828 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3831 fprintf_unfiltered (gdb_stdlog
,
3832 "infrun: handling deferred step\n");
3834 /* Pull the single step breakpoints out of the target. */
3835 if (singlestep_breakpoints_inserted_p
)
3837 remove_single_step_breakpoints ();
3838 singlestep_breakpoints_inserted_p
= 0;
3841 ecs
->event_thread
->control
.trap_expected
= 0;
3843 /* Note: We do not call context_switch at this point, as the
3844 context is already set up for stepping the original thread. */
3845 switch_to_thread (deferred_step_ptid
);
3846 deferred_step_ptid
= null_ptid
;
3847 /* Suppress spurious "Switching to ..." message. */
3848 previous_inferior_ptid
= inferior_ptid
;
3850 resume (1, GDB_SIGNAL_0
);
3851 prepare_to_wait (ecs
);
3855 deferred_step_ptid
= null_ptid
;
3858 /* See if a thread hit a thread-specific breakpoint that was meant for
3859 another thread. If so, then step that thread past the breakpoint,
3862 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
3864 int thread_hop_needed
= 0;
3865 struct address_space
*aspace
=
3866 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
3868 /* Check if a regular breakpoint has been hit before checking
3869 for a potential single step breakpoint. Otherwise, GDB will
3870 not see this breakpoint hit when stepping onto breakpoints. */
3871 if (regular_breakpoint_inserted_here_p (aspace
, stop_pc
))
3873 ecs
->random_signal
= 0;
3874 if (!breakpoint_thread_match (aspace
, stop_pc
, ecs
->ptid
))
3875 thread_hop_needed
= 1;
3877 else if (singlestep_breakpoints_inserted_p
)
3879 /* We have not context switched yet, so this should be true
3880 no matter which thread hit the singlestep breakpoint. */
3881 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
3883 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
3885 target_pid_to_str (ecs
->ptid
));
3887 ecs
->random_signal
= 0;
3888 /* The call to in_thread_list is necessary because PTIDs sometimes
3889 change when we go from single-threaded to multi-threaded. If
3890 the singlestep_ptid is still in the list, assume that it is
3891 really different from ecs->ptid. */
3892 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
3893 && in_thread_list (singlestep_ptid
))
3895 /* If the PC of the thread we were trying to single-step
3896 has changed, discard this event (which we were going
3897 to ignore anyway), and pretend we saw that thread
3898 trap. This prevents us continuously moving the
3899 single-step breakpoint forward, one instruction at a
3900 time. If the PC has changed, then the thread we were
3901 trying to single-step has trapped or been signalled,
3902 but the event has not been reported to GDB yet.
3904 There might be some cases where this loses signal
3905 information, if a signal has arrived at exactly the
3906 same time that the PC changed, but this is the best
3907 we can do with the information available. Perhaps we
3908 should arrange to report all events for all threads
3909 when they stop, or to re-poll the remote looking for
3910 this particular thread (i.e. temporarily enable
3913 CORE_ADDR new_singlestep_pc
3914 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
3916 if (new_singlestep_pc
!= singlestep_pc
)
3918 enum gdb_signal stop_signal
;
3921 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
3922 " but expected thread advanced also\n");
3924 /* The current context still belongs to
3925 singlestep_ptid. Don't swap here, since that's
3926 the context we want to use. Just fudge our
3927 state and continue. */
3928 stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
3929 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3930 ecs
->ptid
= singlestep_ptid
;
3931 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3932 ecs
->event_thread
->suspend
.stop_signal
= stop_signal
;
3933 stop_pc
= new_singlestep_pc
;
3938 fprintf_unfiltered (gdb_stdlog
,
3939 "infrun: unexpected thread\n");
3941 thread_hop_needed
= 1;
3942 stepping_past_singlestep_breakpoint
= 1;
3943 saved_singlestep_ptid
= singlestep_ptid
;
3948 if (thread_hop_needed
)
3950 struct regcache
*thread_regcache
;
3951 int remove_status
= 0;
3954 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
3956 /* Switch context before touching inferior memory, the
3957 previous thread may have exited. */
3958 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
3959 context_switch (ecs
->ptid
);
3961 /* Saw a breakpoint, but it was hit by the wrong thread.
3964 if (singlestep_breakpoints_inserted_p
)
3966 /* Pull the single step breakpoints out of the target. */
3967 remove_single_step_breakpoints ();
3968 singlestep_breakpoints_inserted_p
= 0;
3971 /* If the arch can displace step, don't remove the
3973 thread_regcache
= get_thread_regcache (ecs
->ptid
);
3974 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
3975 remove_status
= remove_breakpoints ();
3977 /* Did we fail to remove breakpoints? If so, try
3978 to set the PC past the bp. (There's at least
3979 one situation in which we can fail to remove
3980 the bp's: On HP-UX's that use ttrace, we can't
3981 change the address space of a vforking child
3982 process until the child exits (well, okay, not
3983 then either :-) or execs. */
3984 if (remove_status
!= 0)
3985 error (_("Cannot step over breakpoint hit in wrong thread"));
3990 /* Only need to require the next event from this
3991 thread in all-stop mode. */
3992 waiton_ptid
= ecs
->ptid
;
3993 infwait_state
= infwait_thread_hop_state
;
3996 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4001 else if (singlestep_breakpoints_inserted_p
)
4003 ecs
->random_signal
= 0;
4007 ecs
->random_signal
= 1;
4009 /* See if something interesting happened to the non-current thread. If
4010 so, then switch to that thread. */
4011 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4014 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
4016 context_switch (ecs
->ptid
);
4018 if (deprecated_context_hook
)
4019 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
4022 /* At this point, get hold of the now-current thread's frame. */
4023 frame
= get_current_frame ();
4024 gdbarch
= get_frame_arch (frame
);
4026 if (singlestep_breakpoints_inserted_p
)
4028 /* Pull the single step breakpoints out of the target. */
4029 remove_single_step_breakpoints ();
4030 singlestep_breakpoints_inserted_p
= 0;
4033 if (stepped_after_stopped_by_watchpoint
)
4034 stopped_by_watchpoint
= 0;
4036 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
4038 /* If necessary, step over this watchpoint. We'll be back to display
4040 if (stopped_by_watchpoint
4041 && (target_have_steppable_watchpoint
4042 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
4044 /* At this point, we are stopped at an instruction which has
4045 attempted to write to a piece of memory under control of
4046 a watchpoint. The instruction hasn't actually executed
4047 yet. If we were to evaluate the watchpoint expression
4048 now, we would get the old value, and therefore no change
4049 would seem to have occurred.
4051 In order to make watchpoints work `right', we really need
4052 to complete the memory write, and then evaluate the
4053 watchpoint expression. We do this by single-stepping the
4056 It may not be necessary to disable the watchpoint to stop over
4057 it. For example, the PA can (with some kernel cooperation)
4058 single step over a watchpoint without disabling the watchpoint.
4060 It is far more common to need to disable a watchpoint to step
4061 the inferior over it. If we have non-steppable watchpoints,
4062 we must disable the current watchpoint; it's simplest to
4063 disable all watchpoints and breakpoints. */
4066 if (!target_have_steppable_watchpoint
)
4068 remove_breakpoints ();
4069 /* See comment in resume why we need to stop bypassing signals
4070 while breakpoints have been removed. */
4071 target_pass_signals (0, NULL
);
4074 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
4075 target_resume (ecs
->ptid
, hw_step
, GDB_SIGNAL_0
);
4076 waiton_ptid
= ecs
->ptid
;
4077 if (target_have_steppable_watchpoint
)
4078 infwait_state
= infwait_step_watch_state
;
4080 infwait_state
= infwait_nonstep_watch_state
;
4081 prepare_to_wait (ecs
);
4085 clear_stop_func (ecs
);
4086 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4087 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4088 ecs
->event_thread
->control
.stop_step
= 0;
4089 stop_print_frame
= 1;
4090 ecs
->random_signal
= 0;
4091 stopped_by_random_signal
= 0;
4093 /* Hide inlined functions starting here, unless we just performed stepi or
4094 nexti. After stepi and nexti, always show the innermost frame (not any
4095 inline function call sites). */
4096 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4098 struct address_space
*aspace
=
4099 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4101 /* skip_inline_frames is expensive, so we avoid it if we can
4102 determine that the address is one where functions cannot have
4103 been inlined. This improves performance with inferiors that
4104 load a lot of shared libraries, because the solib event
4105 breakpoint is defined as the address of a function (i.e. not
4106 inline). Note that we have to check the previous PC as well
4107 as the current one to catch cases when we have just
4108 single-stepped off a breakpoint prior to reinstating it.
4109 Note that we're assuming that the code we single-step to is
4110 not inline, but that's not definitive: there's nothing
4111 preventing the event breakpoint function from containing
4112 inlined code, and the single-step ending up there. If the
4113 user had set a breakpoint on that inlined code, the missing
4114 skip_inline_frames call would break things. Fortunately
4115 that's an extremely unlikely scenario. */
4116 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4117 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4118 && ecs
->event_thread
->control
.trap_expected
4119 && pc_at_non_inline_function (aspace
,
4120 ecs
->event_thread
->prev_pc
,
4122 skip_inline_frames (ecs
->ptid
);
4125 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4126 && ecs
->event_thread
->control
.trap_expected
4127 && gdbarch_single_step_through_delay_p (gdbarch
)
4128 && currently_stepping (ecs
->event_thread
))
4130 /* We're trying to step off a breakpoint. Turns out that we're
4131 also on an instruction that needs to be stepped multiple
4132 times before it's been fully executing. E.g., architectures
4133 with a delay slot. It needs to be stepped twice, once for
4134 the instruction and once for the delay slot. */
4135 int step_through_delay
4136 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4138 if (debug_infrun
&& step_through_delay
)
4139 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4140 if (ecs
->event_thread
->control
.step_range_end
== 0
4141 && step_through_delay
)
4143 /* The user issued a continue when stopped at a breakpoint.
4144 Set up for another trap and get out of here. */
4145 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4149 else if (step_through_delay
)
4151 /* The user issued a step when stopped at a breakpoint.
4152 Maybe we should stop, maybe we should not - the delay
4153 slot *might* correspond to a line of source. In any
4154 case, don't decide that here, just set
4155 ecs->stepping_over_breakpoint, making sure we
4156 single-step again before breakpoints are re-inserted. */
4157 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4161 /* Look at the cause of the stop, and decide what to do.
4162 The alternatives are:
4163 1) stop_stepping and return; to really stop and return to the debugger,
4164 2) keep_going and return to start up again
4165 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
4166 3) set ecs->random_signal to 1, and the decision between 1 and 2
4167 will be made according to the signal handling tables. */
4169 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4170 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4171 || stop_soon
== STOP_QUIETLY_REMOTE
)
4173 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4177 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4178 stop_print_frame
= 0;
4179 stop_stepping (ecs
);
4183 /* This is originated from start_remote(), start_inferior() and
4184 shared libraries hook functions. */
4185 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4188 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4189 stop_stepping (ecs
);
4193 /* This originates from attach_command(). We need to overwrite
4194 the stop_signal here, because some kernels don't ignore a
4195 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4196 See more comments in inferior.h. On the other hand, if we
4197 get a non-SIGSTOP, report it to the user - assume the backend
4198 will handle the SIGSTOP if it should show up later.
4200 Also consider that the attach is complete when we see a
4201 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4202 target extended-remote report it instead of a SIGSTOP
4203 (e.g. gdbserver). We already rely on SIGTRAP being our
4204 signal, so this is no exception.
4206 Also consider that the attach is complete when we see a
4207 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4208 the target to stop all threads of the inferior, in case the
4209 low level attach operation doesn't stop them implicitly. If
4210 they weren't stopped implicitly, then the stub will report a
4211 GDB_SIGNAL_0, meaning: stopped for no particular reason
4212 other than GDB's request. */
4213 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4214 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
4215 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4216 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
4218 stop_stepping (ecs
);
4219 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4223 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4224 handles this event. */
4225 ecs
->event_thread
->control
.stop_bpstat
4226 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4227 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4229 /* Following in case break condition called a
4231 stop_print_frame
= 1;
4233 /* This is where we handle "moribund" watchpoints. Unlike
4234 software breakpoints traps, hardware watchpoint traps are
4235 always distinguishable from random traps. If no high-level
4236 watchpoint is associated with the reported stop data address
4237 anymore, then the bpstat does not explain the signal ---
4238 simply make sure to ignore it if `stopped_by_watchpoint' is
4242 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4243 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4244 && stopped_by_watchpoint
)
4245 fprintf_unfiltered (gdb_stdlog
,
4246 "infrun: no user watchpoint explains "
4247 "watchpoint SIGTRAP, ignoring\n");
4249 /* NOTE: cagney/2003-03-29: These two checks for a random signal
4250 at one stage in the past included checks for an inferior
4251 function call's call dummy's return breakpoint. The original
4252 comment, that went with the test, read:
4254 ``End of a stack dummy. Some systems (e.g. Sony news) give
4255 another signal besides SIGTRAP, so check here as well as
4258 If someone ever tries to get call dummys on a
4259 non-executable stack to work (where the target would stop
4260 with something like a SIGSEGV), then those tests might need
4261 to be re-instated. Given, however, that the tests were only
4262 enabled when momentary breakpoints were not being used, I
4263 suspect that it won't be the case.
4265 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4266 be necessary for call dummies on a non-executable stack on
4269 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4271 = !(bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4272 || stopped_by_watchpoint
4273 || ecs
->event_thread
->control
.trap_expected
4274 || (ecs
->event_thread
->control
.step_range_end
4275 && (ecs
->event_thread
->control
.step_resume_breakpoint
4279 ecs
->random_signal
= !bpstat_explains_signal
4280 (ecs
->event_thread
->control
.stop_bpstat
);
4281 if (!ecs
->random_signal
)
4282 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_TRAP
;
4286 /* When we reach this point, we've pretty much decided
4287 that the reason for stopping must've been a random
4288 (unexpected) signal. */
4291 ecs
->random_signal
= 1;
4293 process_event_stop_test
:
4295 /* Re-fetch current thread's frame in case we did a
4296 "goto process_event_stop_test" above. */
4297 frame
= get_current_frame ();
4298 gdbarch
= get_frame_arch (frame
);
4300 /* For the program's own signals, act according to
4301 the signal handling tables. */
4303 if (ecs
->random_signal
)
4305 /* Signal not for debugging purposes. */
4307 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
4310 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
4311 ecs
->event_thread
->suspend
.stop_signal
);
4313 stopped_by_random_signal
= 1;
4315 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4318 target_terminal_ours_for_output ();
4319 print_signal_received_reason
4320 (ecs
->event_thread
->suspend
.stop_signal
);
4322 /* Always stop on signals if we're either just gaining control
4323 of the program, or the user explicitly requested this thread
4324 to remain stopped. */
4325 if (stop_soon
!= NO_STOP_QUIETLY
4326 || ecs
->event_thread
->stop_requested
4328 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4330 stop_stepping (ecs
);
4333 /* If not going to stop, give terminal back
4334 if we took it away. */
4336 target_terminal_inferior ();
4338 /* Clear the signal if it should not be passed. */
4339 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4340 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4342 if (ecs
->event_thread
->prev_pc
== stop_pc
4343 && ecs
->event_thread
->control
.trap_expected
4344 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4346 /* We were just starting a new sequence, attempting to
4347 single-step off of a breakpoint and expecting a SIGTRAP.
4348 Instead this signal arrives. This signal will take us out
4349 of the stepping range so GDB needs to remember to, when
4350 the signal handler returns, resume stepping off that
4352 /* To simplify things, "continue" is forced to use the same
4353 code paths as single-step - set a breakpoint at the
4354 signal return address and then, once hit, step off that
4357 fprintf_unfiltered (gdb_stdlog
,
4358 "infrun: signal arrived while stepping over "
4361 insert_hp_step_resume_breakpoint_at_frame (frame
);
4362 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4363 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4364 ecs
->event_thread
->control
.trap_expected
= 0;
4369 if (ecs
->event_thread
->control
.step_range_end
!= 0
4370 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4371 && (ecs
->event_thread
->control
.step_range_start
<= stop_pc
4372 && stop_pc
< ecs
->event_thread
->control
.step_range_end
)
4373 && frame_id_eq (get_stack_frame_id (frame
),
4374 ecs
->event_thread
->control
.step_stack_frame_id
)
4375 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4377 /* The inferior is about to take a signal that will take it
4378 out of the single step range. Set a breakpoint at the
4379 current PC (which is presumably where the signal handler
4380 will eventually return) and then allow the inferior to
4383 Note that this is only needed for a signal delivered
4384 while in the single-step range. Nested signals aren't a
4385 problem as they eventually all return. */
4387 fprintf_unfiltered (gdb_stdlog
,
4388 "infrun: signal may take us out of "
4389 "single-step range\n");
4391 insert_hp_step_resume_breakpoint_at_frame (frame
);
4392 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4393 ecs
->event_thread
->control
.trap_expected
= 0;
4398 /* Note: step_resume_breakpoint may be non-NULL. This occures
4399 when either there's a nested signal, or when there's a
4400 pending signal enabled just as the signal handler returns
4401 (leaving the inferior at the step-resume-breakpoint without
4402 actually executing it). Either way continue until the
4403 breakpoint is really hit. */
4408 /* Handle cases caused by hitting a breakpoint. */
4410 CORE_ADDR jmp_buf_pc
;
4411 struct bpstat_what what
;
4413 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4415 if (what
.call_dummy
)
4417 stop_stack_dummy
= what
.call_dummy
;
4420 /* If we hit an internal event that triggers symbol changes, the
4421 current frame will be invalidated within bpstat_what (e.g., if
4422 we hit an internal solib event). Re-fetch it. */
4423 frame
= get_current_frame ();
4424 gdbarch
= get_frame_arch (frame
);
4426 switch (what
.main_action
)
4428 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4429 /* If we hit the breakpoint at longjmp while stepping, we
4430 install a momentary breakpoint at the target of the
4434 fprintf_unfiltered (gdb_stdlog
,
4435 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4437 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4439 if (what
.is_longjmp
)
4441 struct value
*arg_value
;
4443 /* If we set the longjmp breakpoint via a SystemTap probe,
4444 then use it to extract the arguments. The destination
4445 PC is the third argument to the probe. */
4446 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4448 jmp_buf_pc
= value_as_address (arg_value
);
4449 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4450 || !gdbarch_get_longjmp_target (gdbarch
,
4451 frame
, &jmp_buf_pc
))
4454 fprintf_unfiltered (gdb_stdlog
,
4455 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4456 "(!gdbarch_get_longjmp_target)\n");
4461 /* We're going to replace the current step-resume breakpoint
4462 with a longjmp-resume breakpoint. */
4463 delete_step_resume_breakpoint (ecs
->event_thread
);
4465 /* Insert a breakpoint at resume address. */
4466 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4469 check_exception_resume (ecs
, frame
);
4473 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4475 fprintf_unfiltered (gdb_stdlog
,
4476 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4478 if (what
.is_longjmp
)
4480 gdb_assert (ecs
->event_thread
->control
.step_resume_breakpoint
4482 delete_step_resume_breakpoint (ecs
->event_thread
);
4486 /* There are several cases to consider.
4488 1. The initiating frame no longer exists. In this case
4489 we must stop, because the exception has gone too far.
4491 2. The initiating frame exists, and is the same as the
4492 current frame. We stop, because the exception has been
4495 3. The initiating frame exists and is different from
4496 the current frame. This means the exception has been
4497 caught beneath the initiating frame, so keep going. */
4498 struct frame_info
*init_frame
4499 = frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4501 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4503 delete_exception_resume_breakpoint (ecs
->event_thread
);
4507 struct frame_id current_id
4508 = get_frame_id (get_current_frame ());
4509 if (frame_id_eq (current_id
,
4510 ecs
->event_thread
->initiating_frame
))
4512 /* Case 2. Fall through. */
4522 /* For Cases 1 and 2, remove the step-resume breakpoint,
4524 delete_step_resume_breakpoint (ecs
->event_thread
);
4527 ecs
->event_thread
->control
.stop_step
= 1;
4528 print_end_stepping_range_reason ();
4529 stop_stepping (ecs
);
4532 case BPSTAT_WHAT_SINGLE
:
4534 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4535 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4536 /* Still need to check other stuff, at least the case
4537 where we are stepping and step out of the right range. */
4540 case BPSTAT_WHAT_STEP_RESUME
:
4542 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4544 delete_step_resume_breakpoint (ecs
->event_thread
);
4545 if (ecs
->event_thread
->control
.proceed_to_finish
4546 && execution_direction
== EXEC_REVERSE
)
4548 struct thread_info
*tp
= ecs
->event_thread
;
4550 /* We are finishing a function in reverse, and just hit
4551 the step-resume breakpoint at the start address of the
4552 function, and we're almost there -- just need to back
4553 up by one more single-step, which should take us back
4554 to the function call. */
4555 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4559 fill_in_stop_func (gdbarch
, ecs
);
4560 if (stop_pc
== ecs
->stop_func_start
4561 && execution_direction
== EXEC_REVERSE
)
4563 /* We are stepping over a function call in reverse, and
4564 just hit the step-resume breakpoint at the start
4565 address of the function. Go back to single-stepping,
4566 which should take us back to the function call. */
4567 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4573 case BPSTAT_WHAT_STOP_NOISY
:
4575 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4576 stop_print_frame
= 1;
4578 /* We are about to nuke the step_resume_breakpointt via the
4579 cleanup chain, so no need to worry about it here. */
4581 stop_stepping (ecs
);
4584 case BPSTAT_WHAT_STOP_SILENT
:
4586 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4587 stop_print_frame
= 0;
4589 /* We are about to nuke the step_resume_breakpoin via the
4590 cleanup chain, so no need to worry about it here. */
4592 stop_stepping (ecs
);
4595 case BPSTAT_WHAT_HP_STEP_RESUME
:
4597 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4599 delete_step_resume_breakpoint (ecs
->event_thread
);
4600 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4602 /* Back when the step-resume breakpoint was inserted, we
4603 were trying to single-step off a breakpoint. Go back
4605 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4606 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4612 case BPSTAT_WHAT_KEEP_CHECKING
:
4617 /* We come here if we hit a breakpoint but should not
4618 stop for it. Possibly we also were stepping
4619 and should stop for that. So fall through and
4620 test for stepping. But, if not stepping,
4623 /* In all-stop mode, if we're currently stepping but have stopped in
4624 some other thread, we need to switch back to the stepped thread. */
4627 struct thread_info
*tp
;
4629 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
4633 /* However, if the current thread is blocked on some internal
4634 breakpoint, and we simply need to step over that breakpoint
4635 to get it going again, do that first. */
4636 if ((ecs
->event_thread
->control
.trap_expected
4637 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
4638 || ecs
->event_thread
->stepping_over_breakpoint
)
4644 /* If the stepping thread exited, then don't try to switch
4645 back and resume it, which could fail in several different
4646 ways depending on the target. Instead, just keep going.
4648 We can find a stepping dead thread in the thread list in
4651 - The target supports thread exit events, and when the
4652 target tries to delete the thread from the thread list,
4653 inferior_ptid pointed at the exiting thread. In such
4654 case, calling delete_thread does not really remove the
4655 thread from the list; instead, the thread is left listed,
4656 with 'exited' state.
4658 - The target's debug interface does not support thread
4659 exit events, and so we have no idea whatsoever if the
4660 previously stepping thread is still alive. For that
4661 reason, we need to synchronously query the target
4663 if (is_exited (tp
->ptid
)
4664 || !target_thread_alive (tp
->ptid
))
4667 fprintf_unfiltered (gdb_stdlog
,
4668 "infrun: not switching back to "
4669 "stepped thread, it has vanished\n");
4671 delete_thread (tp
->ptid
);
4676 /* Otherwise, we no longer expect a trap in the current thread.
4677 Clear the trap_expected flag before switching back -- this is
4678 what keep_going would do as well, if we called it. */
4679 ecs
->event_thread
->control
.trap_expected
= 0;
4682 fprintf_unfiltered (gdb_stdlog
,
4683 "infrun: switching back to stepped thread\n");
4685 ecs
->event_thread
= tp
;
4686 ecs
->ptid
= tp
->ptid
;
4687 context_switch (ecs
->ptid
);
4693 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4696 fprintf_unfiltered (gdb_stdlog
,
4697 "infrun: step-resume breakpoint is inserted\n");
4699 /* Having a step-resume breakpoint overrides anything
4700 else having to do with stepping commands until
4701 that breakpoint is reached. */
4706 if (ecs
->event_thread
->control
.step_range_end
== 0)
4709 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4710 /* Likewise if we aren't even stepping. */
4715 /* Re-fetch current thread's frame in case the code above caused
4716 the frame cache to be re-initialized, making our FRAME variable
4717 a dangling pointer. */
4718 frame
= get_current_frame ();
4719 gdbarch
= get_frame_arch (frame
);
4720 fill_in_stop_func (gdbarch
, ecs
);
4722 /* If stepping through a line, keep going if still within it.
4724 Note that step_range_end is the address of the first instruction
4725 beyond the step range, and NOT the address of the last instruction
4728 Note also that during reverse execution, we may be stepping
4729 through a function epilogue and therefore must detect when
4730 the current-frame changes in the middle of a line. */
4732 if (stop_pc
>= ecs
->event_thread
->control
.step_range_start
4733 && stop_pc
< ecs
->event_thread
->control
.step_range_end
4734 && (execution_direction
!= EXEC_REVERSE
4735 || frame_id_eq (get_frame_id (frame
),
4736 ecs
->event_thread
->control
.step_frame_id
)))
4740 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4741 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4742 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4744 /* When stepping backward, stop at beginning of line range
4745 (unless it's the function entry point, in which case
4746 keep going back to the call point). */
4747 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4748 && stop_pc
!= ecs
->stop_func_start
4749 && execution_direction
== EXEC_REVERSE
)
4751 ecs
->event_thread
->control
.stop_step
= 1;
4752 print_end_stepping_range_reason ();
4753 stop_stepping (ecs
);
4761 /* We stepped out of the stepping range. */
4763 /* If we are stepping at the source level and entered the runtime
4764 loader dynamic symbol resolution code...
4766 EXEC_FORWARD: we keep on single stepping until we exit the run
4767 time loader code and reach the callee's address.
4769 EXEC_REVERSE: we've already executed the callee (backward), and
4770 the runtime loader code is handled just like any other
4771 undebuggable function call. Now we need only keep stepping
4772 backward through the trampoline code, and that's handled further
4773 down, so there is nothing for us to do here. */
4775 if (execution_direction
!= EXEC_REVERSE
4776 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4777 && in_solib_dynsym_resolve_code (stop_pc
))
4779 CORE_ADDR pc_after_resolver
=
4780 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
4783 fprintf_unfiltered (gdb_stdlog
,
4784 "infrun: stepped into dynsym resolve code\n");
4786 if (pc_after_resolver
)
4788 /* Set up a step-resume breakpoint at the address
4789 indicated by SKIP_SOLIB_RESOLVER. */
4790 struct symtab_and_line sr_sal
;
4793 sr_sal
.pc
= pc_after_resolver
;
4794 sr_sal
.pspace
= get_frame_program_space (frame
);
4796 insert_step_resume_breakpoint_at_sal (gdbarch
,
4797 sr_sal
, null_frame_id
);
4804 if (ecs
->event_thread
->control
.step_range_end
!= 1
4805 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4806 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4807 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
4810 fprintf_unfiltered (gdb_stdlog
,
4811 "infrun: stepped into signal trampoline\n");
4812 /* The inferior, while doing a "step" or "next", has ended up in
4813 a signal trampoline (either by a signal being delivered or by
4814 the signal handler returning). Just single-step until the
4815 inferior leaves the trampoline (either by calling the handler
4821 /* If we're in the return path from a shared library trampoline,
4822 we want to proceed through the trampoline when stepping. */
4823 /* macro/2012-04-25: This needs to come before the subroutine
4824 call check below as on some targets return trampolines look
4825 like subroutine calls (MIPS16 return thunks). */
4826 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4827 stop_pc
, ecs
->stop_func_name
)
4828 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
4830 /* Determine where this trampoline returns. */
4831 CORE_ADDR real_stop_pc
;
4833 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4836 fprintf_unfiltered (gdb_stdlog
,
4837 "infrun: stepped into solib return tramp\n");
4839 /* Only proceed through if we know where it's going. */
4842 /* And put the step-breakpoint there and go until there. */
4843 struct symtab_and_line sr_sal
;
4845 init_sal (&sr_sal
); /* initialize to zeroes */
4846 sr_sal
.pc
= real_stop_pc
;
4847 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4848 sr_sal
.pspace
= get_frame_program_space (frame
);
4850 /* Do not specify what the fp should be when we stop since
4851 on some machines the prologue is where the new fp value
4853 insert_step_resume_breakpoint_at_sal (gdbarch
,
4854 sr_sal
, null_frame_id
);
4856 /* Restart without fiddling with the step ranges or
4863 /* Check for subroutine calls. The check for the current frame
4864 equalling the step ID is not necessary - the check of the
4865 previous frame's ID is sufficient - but it is a common case and
4866 cheaper than checking the previous frame's ID.
4868 NOTE: frame_id_eq will never report two invalid frame IDs as
4869 being equal, so to get into this block, both the current and
4870 previous frame must have valid frame IDs. */
4871 /* The outer_frame_id check is a heuristic to detect stepping
4872 through startup code. If we step over an instruction which
4873 sets the stack pointer from an invalid value to a valid value,
4874 we may detect that as a subroutine call from the mythical
4875 "outermost" function. This could be fixed by marking
4876 outermost frames as !stack_p,code_p,special_p. Then the
4877 initial outermost frame, before sp was valid, would
4878 have code_addr == &_start. See the comment in frame_id_eq
4880 if (!frame_id_eq (get_stack_frame_id (frame
),
4881 ecs
->event_thread
->control
.step_stack_frame_id
)
4882 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4883 ecs
->event_thread
->control
.step_stack_frame_id
)
4884 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
4886 || step_start_function
!= find_pc_function (stop_pc
))))
4888 CORE_ADDR real_stop_pc
;
4891 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
4893 if ((ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
4894 || ((ecs
->event_thread
->control
.step_range_end
== 1)
4895 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
4896 ecs
->stop_func_start
)))
4898 /* I presume that step_over_calls is only 0 when we're
4899 supposed to be stepping at the assembly language level
4900 ("stepi"). Just stop. */
4901 /* Also, maybe we just did a "nexti" inside a prolog, so we
4902 thought it was a subroutine call but it was not. Stop as
4904 /* And this works the same backward as frontward. MVS */
4905 ecs
->event_thread
->control
.stop_step
= 1;
4906 print_end_stepping_range_reason ();
4907 stop_stepping (ecs
);
4911 /* Reverse stepping through solib trampolines. */
4913 if (execution_direction
== EXEC_REVERSE
4914 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
4915 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4916 || (ecs
->stop_func_start
== 0
4917 && in_solib_dynsym_resolve_code (stop_pc
))))
4919 /* Any solib trampoline code can be handled in reverse
4920 by simply continuing to single-step. We have already
4921 executed the solib function (backwards), and a few
4922 steps will take us back through the trampoline to the
4928 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4930 /* We're doing a "next".
4932 Normal (forward) execution: set a breakpoint at the
4933 callee's return address (the address at which the caller
4936 Reverse (backward) execution. set the step-resume
4937 breakpoint at the start of the function that we just
4938 stepped into (backwards), and continue to there. When we
4939 get there, we'll need to single-step back to the caller. */
4941 if (execution_direction
== EXEC_REVERSE
)
4943 struct symtab_and_line sr_sal
;
4945 /* Normal function call return (static or dynamic). */
4947 sr_sal
.pc
= ecs
->stop_func_start
;
4948 sr_sal
.pspace
= get_frame_program_space (frame
);
4949 insert_step_resume_breakpoint_at_sal (gdbarch
,
4950 sr_sal
, null_frame_id
);
4953 insert_step_resume_breakpoint_at_caller (frame
);
4959 /* If we are in a function call trampoline (a stub between the
4960 calling routine and the real function), locate the real
4961 function. That's what tells us (a) whether we want to step
4962 into it at all, and (b) what prologue we want to run to the
4963 end of, if we do step into it. */
4964 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
4965 if (real_stop_pc
== 0)
4966 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4967 if (real_stop_pc
!= 0)
4968 ecs
->stop_func_start
= real_stop_pc
;
4970 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
4972 struct symtab_and_line sr_sal
;
4975 sr_sal
.pc
= ecs
->stop_func_start
;
4976 sr_sal
.pspace
= get_frame_program_space (frame
);
4978 insert_step_resume_breakpoint_at_sal (gdbarch
,
4979 sr_sal
, null_frame_id
);
4984 /* If we have line number information for the function we are
4985 thinking of stepping into and the function isn't on the skip
4988 If there are several symtabs at that PC (e.g. with include
4989 files), just want to know whether *any* of them have line
4990 numbers. find_pc_line handles this. */
4992 struct symtab_and_line tmp_sal
;
4994 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4995 if (tmp_sal
.line
!= 0
4996 && !function_pc_is_marked_for_skip (ecs
->stop_func_start
))
4998 if (execution_direction
== EXEC_REVERSE
)
4999 handle_step_into_function_backward (gdbarch
, ecs
);
5001 handle_step_into_function (gdbarch
, ecs
);
5006 /* If we have no line number and the step-stop-if-no-debug is
5007 set, we stop the step so that the user has a chance to switch
5008 in assembly mode. */
5009 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5010 && step_stop_if_no_debug
)
5012 ecs
->event_thread
->control
.stop_step
= 1;
5013 print_end_stepping_range_reason ();
5014 stop_stepping (ecs
);
5018 if (execution_direction
== EXEC_REVERSE
)
5020 /* Set a breakpoint at callee's start address.
5021 From there we can step once and be back in the caller. */
5022 struct symtab_and_line sr_sal
;
5025 sr_sal
.pc
= ecs
->stop_func_start
;
5026 sr_sal
.pspace
= get_frame_program_space (frame
);
5027 insert_step_resume_breakpoint_at_sal (gdbarch
,
5028 sr_sal
, null_frame_id
);
5031 /* Set a breakpoint at callee's return address (the address
5032 at which the caller will resume). */
5033 insert_step_resume_breakpoint_at_caller (frame
);
5039 /* Reverse stepping through solib trampolines. */
5041 if (execution_direction
== EXEC_REVERSE
5042 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5044 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5045 || (ecs
->stop_func_start
== 0
5046 && in_solib_dynsym_resolve_code (stop_pc
)))
5048 /* Any solib trampoline code can be handled in reverse
5049 by simply continuing to single-step. We have already
5050 executed the solib function (backwards), and a few
5051 steps will take us back through the trampoline to the
5056 else if (in_solib_dynsym_resolve_code (stop_pc
))
5058 /* Stepped backward into the solib dynsym resolver.
5059 Set a breakpoint at its start and continue, then
5060 one more step will take us out. */
5061 struct symtab_and_line sr_sal
;
5064 sr_sal
.pc
= ecs
->stop_func_start
;
5065 sr_sal
.pspace
= get_frame_program_space (frame
);
5066 insert_step_resume_breakpoint_at_sal (gdbarch
,
5067 sr_sal
, null_frame_id
);
5073 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5075 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5076 the trampoline processing logic, however, there are some trampolines
5077 that have no names, so we should do trampoline handling first. */
5078 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5079 && ecs
->stop_func_name
== NULL
5080 && stop_pc_sal
.line
== 0)
5083 fprintf_unfiltered (gdb_stdlog
,
5084 "infrun: stepped into undebuggable function\n");
5086 /* The inferior just stepped into, or returned to, an
5087 undebuggable function (where there is no debugging information
5088 and no line number corresponding to the address where the
5089 inferior stopped). Since we want to skip this kind of code,
5090 we keep going until the inferior returns from this
5091 function - unless the user has asked us not to (via
5092 set step-mode) or we no longer know how to get back
5093 to the call site. */
5094 if (step_stop_if_no_debug
5095 || !frame_id_p (frame_unwind_caller_id (frame
)))
5097 /* If we have no line number and the step-stop-if-no-debug
5098 is set, we stop the step so that the user has a chance to
5099 switch in assembly mode. */
5100 ecs
->event_thread
->control
.stop_step
= 1;
5101 print_end_stepping_range_reason ();
5102 stop_stepping (ecs
);
5107 /* Set a breakpoint at callee's return address (the address
5108 at which the caller will resume). */
5109 insert_step_resume_breakpoint_at_caller (frame
);
5115 if (ecs
->event_thread
->control
.step_range_end
== 1)
5117 /* It is stepi or nexti. We always want to stop stepping after
5120 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5121 ecs
->event_thread
->control
.stop_step
= 1;
5122 print_end_stepping_range_reason ();
5123 stop_stepping (ecs
);
5127 if (stop_pc_sal
.line
== 0)
5129 /* We have no line number information. That means to stop
5130 stepping (does this always happen right after one instruction,
5131 when we do "s" in a function with no line numbers,
5132 or can this happen as a result of a return or longjmp?). */
5134 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5135 ecs
->event_thread
->control
.stop_step
= 1;
5136 print_end_stepping_range_reason ();
5137 stop_stepping (ecs
);
5141 /* Look for "calls" to inlined functions, part one. If the inline
5142 frame machinery detected some skipped call sites, we have entered
5143 a new inline function. */
5145 if (frame_id_eq (get_frame_id (get_current_frame ()),
5146 ecs
->event_thread
->control
.step_frame_id
)
5147 && inline_skipped_frames (ecs
->ptid
))
5149 struct symtab_and_line call_sal
;
5152 fprintf_unfiltered (gdb_stdlog
,
5153 "infrun: stepped into inlined function\n");
5155 find_frame_sal (get_current_frame (), &call_sal
);
5157 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5159 /* For "step", we're going to stop. But if the call site
5160 for this inlined function is on the same source line as
5161 we were previously stepping, go down into the function
5162 first. Otherwise stop at the call site. */
5164 if (call_sal
.line
== ecs
->event_thread
->current_line
5165 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5166 step_into_inline_frame (ecs
->ptid
);
5168 ecs
->event_thread
->control
.stop_step
= 1;
5169 print_end_stepping_range_reason ();
5170 stop_stepping (ecs
);
5175 /* For "next", we should stop at the call site if it is on a
5176 different source line. Otherwise continue through the
5177 inlined function. */
5178 if (call_sal
.line
== ecs
->event_thread
->current_line
5179 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5183 ecs
->event_thread
->control
.stop_step
= 1;
5184 print_end_stepping_range_reason ();
5185 stop_stepping (ecs
);
5191 /* Look for "calls" to inlined functions, part two. If we are still
5192 in the same real function we were stepping through, but we have
5193 to go further up to find the exact frame ID, we are stepping
5194 through a more inlined call beyond its call site. */
5196 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5197 && !frame_id_eq (get_frame_id (get_current_frame ()),
5198 ecs
->event_thread
->control
.step_frame_id
)
5199 && stepped_in_from (get_current_frame (),
5200 ecs
->event_thread
->control
.step_frame_id
))
5203 fprintf_unfiltered (gdb_stdlog
,
5204 "infrun: stepping through inlined function\n");
5206 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5210 ecs
->event_thread
->control
.stop_step
= 1;
5211 print_end_stepping_range_reason ();
5212 stop_stepping (ecs
);
5217 if ((stop_pc
== stop_pc_sal
.pc
)
5218 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5219 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5221 /* We are at the start of a different line. So stop. Note that
5222 we don't stop if we step into the middle of a different line.
5223 That is said to make things like for (;;) statements work
5226 fprintf_unfiltered (gdb_stdlog
,
5227 "infrun: stepped to a different line\n");
5228 ecs
->event_thread
->control
.stop_step
= 1;
5229 print_end_stepping_range_reason ();
5230 stop_stepping (ecs
);
5234 /* We aren't done stepping.
5236 Optimize by setting the stepping range to the line.
5237 (We might not be in the original line, but if we entered a
5238 new line in mid-statement, we continue stepping. This makes
5239 things like for(;;) statements work better.) */
5241 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5242 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5243 set_step_info (frame
, stop_pc_sal
);
5246 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5250 /* Is thread TP in the middle of single-stepping? */
5253 currently_stepping (struct thread_info
*tp
)
5255 return ((tp
->control
.step_range_end
5256 && tp
->control
.step_resume_breakpoint
== NULL
)
5257 || tp
->control
.trap_expected
5258 || bpstat_should_step ());
5261 /* Returns true if any thread *but* the one passed in "data" is in the
5262 middle of stepping or of handling a "next". */
5265 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
5270 return (tp
->control
.step_range_end
5271 || tp
->control
.trap_expected
);
5274 /* Inferior has stepped into a subroutine call with source code that
5275 we should not step over. Do step to the first line of code in
5279 handle_step_into_function (struct gdbarch
*gdbarch
,
5280 struct execution_control_state
*ecs
)
5283 struct symtab_and_line stop_func_sal
, sr_sal
;
5285 fill_in_stop_func (gdbarch
, ecs
);
5287 s
= find_pc_symtab (stop_pc
);
5288 if (s
&& s
->language
!= language_asm
)
5289 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5290 ecs
->stop_func_start
);
5292 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5293 /* Use the step_resume_break to step until the end of the prologue,
5294 even if that involves jumps (as it seems to on the vax under
5296 /* If the prologue ends in the middle of a source line, continue to
5297 the end of that source line (if it is still within the function).
5298 Otherwise, just go to end of prologue. */
5299 if (stop_func_sal
.end
5300 && stop_func_sal
.pc
!= ecs
->stop_func_start
5301 && stop_func_sal
.end
< ecs
->stop_func_end
)
5302 ecs
->stop_func_start
= stop_func_sal
.end
;
5304 /* Architectures which require breakpoint adjustment might not be able
5305 to place a breakpoint at the computed address. If so, the test
5306 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5307 ecs->stop_func_start to an address at which a breakpoint may be
5308 legitimately placed.
5310 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5311 made, GDB will enter an infinite loop when stepping through
5312 optimized code consisting of VLIW instructions which contain
5313 subinstructions corresponding to different source lines. On
5314 FR-V, it's not permitted to place a breakpoint on any but the
5315 first subinstruction of a VLIW instruction. When a breakpoint is
5316 set, GDB will adjust the breakpoint address to the beginning of
5317 the VLIW instruction. Thus, we need to make the corresponding
5318 adjustment here when computing the stop address. */
5320 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5322 ecs
->stop_func_start
5323 = gdbarch_adjust_breakpoint_address (gdbarch
,
5324 ecs
->stop_func_start
);
5327 if (ecs
->stop_func_start
== stop_pc
)
5329 /* We are already there: stop now. */
5330 ecs
->event_thread
->control
.stop_step
= 1;
5331 print_end_stepping_range_reason ();
5332 stop_stepping (ecs
);
5337 /* Put the step-breakpoint there and go until there. */
5338 init_sal (&sr_sal
); /* initialize to zeroes */
5339 sr_sal
.pc
= ecs
->stop_func_start
;
5340 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5341 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5343 /* Do not specify what the fp should be when we stop since on
5344 some machines the prologue is where the new fp value is
5346 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5348 /* And make sure stepping stops right away then. */
5349 ecs
->event_thread
->control
.step_range_end
5350 = ecs
->event_thread
->control
.step_range_start
;
5355 /* Inferior has stepped backward into a subroutine call with source
5356 code that we should not step over. Do step to the beginning of the
5357 last line of code in it. */
5360 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5361 struct execution_control_state
*ecs
)
5364 struct symtab_and_line stop_func_sal
;
5366 fill_in_stop_func (gdbarch
, ecs
);
5368 s
= find_pc_symtab (stop_pc
);
5369 if (s
&& s
->language
!= language_asm
)
5370 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5371 ecs
->stop_func_start
);
5373 stop_func_sal
= find_pc_line (stop_pc
, 0);
5375 /* OK, we're just going to keep stepping here. */
5376 if (stop_func_sal
.pc
== stop_pc
)
5378 /* We're there already. Just stop stepping now. */
5379 ecs
->event_thread
->control
.stop_step
= 1;
5380 print_end_stepping_range_reason ();
5381 stop_stepping (ecs
);
5385 /* Else just reset the step range and keep going.
5386 No step-resume breakpoint, they don't work for
5387 epilogues, which can have multiple entry paths. */
5388 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5389 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5395 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5396 This is used to both functions and to skip over code. */
5399 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5400 struct symtab_and_line sr_sal
,
5401 struct frame_id sr_id
,
5402 enum bptype sr_type
)
5404 /* There should never be more than one step-resume or longjmp-resume
5405 breakpoint per thread, so we should never be setting a new
5406 step_resume_breakpoint when one is already active. */
5407 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5408 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5411 fprintf_unfiltered (gdb_stdlog
,
5412 "infrun: inserting step-resume breakpoint at %s\n",
5413 paddress (gdbarch
, sr_sal
.pc
));
5415 inferior_thread ()->control
.step_resume_breakpoint
5416 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5420 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5421 struct symtab_and_line sr_sal
,
5422 struct frame_id sr_id
)
5424 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5429 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5430 This is used to skip a potential signal handler.
5432 This is called with the interrupted function's frame. The signal
5433 handler, when it returns, will resume the interrupted function at
5437 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5439 struct symtab_and_line sr_sal
;
5440 struct gdbarch
*gdbarch
;
5442 gdb_assert (return_frame
!= NULL
);
5443 init_sal (&sr_sal
); /* initialize to zeros */
5445 gdbarch
= get_frame_arch (return_frame
);
5446 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5447 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5448 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5450 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5451 get_stack_frame_id (return_frame
),
5455 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5456 is used to skip a function after stepping into it (for "next" or if
5457 the called function has no debugging information).
5459 The current function has almost always been reached by single
5460 stepping a call or return instruction. NEXT_FRAME belongs to the
5461 current function, and the breakpoint will be set at the caller's
5464 This is a separate function rather than reusing
5465 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5466 get_prev_frame, which may stop prematurely (see the implementation
5467 of frame_unwind_caller_id for an example). */
5470 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5472 struct symtab_and_line sr_sal
;
5473 struct gdbarch
*gdbarch
;
5475 /* We shouldn't have gotten here if we don't know where the call site
5477 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5479 init_sal (&sr_sal
); /* initialize to zeros */
5481 gdbarch
= frame_unwind_caller_arch (next_frame
);
5482 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5483 frame_unwind_caller_pc (next_frame
));
5484 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5485 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5487 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5488 frame_unwind_caller_id (next_frame
));
5491 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5492 new breakpoint at the target of a jmp_buf. The handling of
5493 longjmp-resume uses the same mechanisms used for handling
5494 "step-resume" breakpoints. */
5497 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5499 /* There should never be more than one step-resume or longjmp-resume
5500 breakpoint per thread, so we should never be setting a new
5501 longjmp_resume_breakpoint when one is already active. */
5502 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5505 fprintf_unfiltered (gdb_stdlog
,
5506 "infrun: inserting longjmp-resume breakpoint at %s\n",
5507 paddress (gdbarch
, pc
));
5509 inferior_thread ()->control
.step_resume_breakpoint
=
5510 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5513 /* Insert an exception resume breakpoint. TP is the thread throwing
5514 the exception. The block B is the block of the unwinder debug hook
5515 function. FRAME is the frame corresponding to the call to this
5516 function. SYM is the symbol of the function argument holding the
5517 target PC of the exception. */
5520 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5522 struct frame_info
*frame
,
5525 volatile struct gdb_exception e
;
5527 /* We want to ignore errors here. */
5528 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5530 struct symbol
*vsym
;
5531 struct value
*value
;
5533 struct breakpoint
*bp
;
5535 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5536 value
= read_var_value (vsym
, frame
);
5537 /* If the value was optimized out, revert to the old behavior. */
5538 if (! value_optimized_out (value
))
5540 handler
= value_as_address (value
);
5543 fprintf_unfiltered (gdb_stdlog
,
5544 "infrun: exception resume at %lx\n",
5545 (unsigned long) handler
);
5547 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5548 handler
, bp_exception_resume
);
5550 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5553 bp
->thread
= tp
->num
;
5554 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5559 /* A helper for check_exception_resume that sets an
5560 exception-breakpoint based on a SystemTap probe. */
5563 insert_exception_resume_from_probe (struct thread_info
*tp
,
5564 const struct probe
*probe
,
5565 struct objfile
*objfile
,
5566 struct frame_info
*frame
)
5568 struct value
*arg_value
;
5570 struct breakpoint
*bp
;
5572 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
5576 handler
= value_as_address (arg_value
);
5579 fprintf_unfiltered (gdb_stdlog
,
5580 "infrun: exception resume at %s\n",
5581 paddress (get_objfile_arch (objfile
),
5584 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5585 handler
, bp_exception_resume
);
5586 bp
->thread
= tp
->num
;
5587 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5590 /* This is called when an exception has been intercepted. Check to
5591 see whether the exception's destination is of interest, and if so,
5592 set an exception resume breakpoint there. */
5595 check_exception_resume (struct execution_control_state
*ecs
,
5596 struct frame_info
*frame
)
5598 volatile struct gdb_exception e
;
5599 struct objfile
*objfile
;
5600 const struct probe
*probe
;
5601 struct symbol
*func
;
5603 /* First see if this exception unwinding breakpoint was set via a
5604 SystemTap probe point. If so, the probe has two arguments: the
5605 CFA and the HANDLER. We ignore the CFA, extract the handler, and
5606 set a breakpoint there. */
5607 probe
= find_probe_by_pc (get_frame_pc (frame
), &objfile
);
5610 insert_exception_resume_from_probe (ecs
->event_thread
, probe
,
5615 func
= get_frame_function (frame
);
5619 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5622 struct block_iterator iter
;
5626 /* The exception breakpoint is a thread-specific breakpoint on
5627 the unwinder's debug hook, declared as:
5629 void _Unwind_DebugHook (void *cfa, void *handler);
5631 The CFA argument indicates the frame to which control is
5632 about to be transferred. HANDLER is the destination PC.
5634 We ignore the CFA and set a temporary breakpoint at HANDLER.
5635 This is not extremely efficient but it avoids issues in gdb
5636 with computing the DWARF CFA, and it also works even in weird
5637 cases such as throwing an exception from inside a signal
5640 b
= SYMBOL_BLOCK_VALUE (func
);
5641 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
5643 if (!SYMBOL_IS_ARGUMENT (sym
))
5650 insert_exception_resume_breakpoint (ecs
->event_thread
,
5659 stop_stepping (struct execution_control_state
*ecs
)
5662 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
5664 /* Let callers know we don't want to wait for the inferior anymore. */
5665 ecs
->wait_some_more
= 0;
5668 /* This function handles various cases where we need to continue
5669 waiting for the inferior. */
5670 /* (Used to be the keep_going: label in the old wait_for_inferior). */
5673 keep_going (struct execution_control_state
*ecs
)
5675 /* Make sure normal_stop is called if we get a QUIT handled before
5677 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
5679 /* Save the pc before execution, to compare with pc after stop. */
5680 ecs
->event_thread
->prev_pc
5681 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5683 /* If we did not do break;, it means we should keep running the
5684 inferior and not return to debugger. */
5686 if (ecs
->event_thread
->control
.trap_expected
5687 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5689 /* We took a signal (which we are supposed to pass through to
5690 the inferior, else we'd not get here) and we haven't yet
5691 gotten our trap. Simply continue. */
5693 discard_cleanups (old_cleanups
);
5694 resume (currently_stepping (ecs
->event_thread
),
5695 ecs
->event_thread
->suspend
.stop_signal
);
5699 /* Either the trap was not expected, but we are continuing
5700 anyway (the user asked that this signal be passed to the
5703 The signal was SIGTRAP, e.g. it was our signal, but we
5704 decided we should resume from it.
5706 We're going to run this baby now!
5708 Note that insert_breakpoints won't try to re-insert
5709 already inserted breakpoints. Therefore, we don't
5710 care if breakpoints were already inserted, or not. */
5712 if (ecs
->event_thread
->stepping_over_breakpoint
)
5714 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
5716 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
5717 /* Since we can't do a displaced step, we have to remove
5718 the breakpoint while we step it. To keep things
5719 simple, we remove them all. */
5720 remove_breakpoints ();
5724 volatile struct gdb_exception e
;
5726 /* Stop stepping when inserting breakpoints
5728 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5730 insert_breakpoints ();
5734 exception_print (gdb_stderr
, e
);
5735 stop_stepping (ecs
);
5740 ecs
->event_thread
->control
.trap_expected
5741 = ecs
->event_thread
->stepping_over_breakpoint
;
5743 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
5744 specifies that such a signal should be delivered to the
5747 Typically, this would occure when a user is debugging a
5748 target monitor on a simulator: the target monitor sets a
5749 breakpoint; the simulator encounters this break-point and
5750 halts the simulation handing control to GDB; GDB, noteing
5751 that the break-point isn't valid, returns control back to the
5752 simulator; the simulator then delivers the hardware
5753 equivalent of a SIGNAL_TRAP to the program being debugged. */
5755 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5756 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5757 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5759 discard_cleanups (old_cleanups
);
5760 resume (currently_stepping (ecs
->event_thread
),
5761 ecs
->event_thread
->suspend
.stop_signal
);
5764 prepare_to_wait (ecs
);
5767 /* This function normally comes after a resume, before
5768 handle_inferior_event exits. It takes care of any last bits of
5769 housekeeping, and sets the all-important wait_some_more flag. */
5772 prepare_to_wait (struct execution_control_state
*ecs
)
5775 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
5777 /* This is the old end of the while loop. Let everybody know we
5778 want to wait for the inferior some more and get called again
5780 ecs
->wait_some_more
= 1;
5783 /* Several print_*_reason functions to print why the inferior has stopped.
5784 We always print something when the inferior exits, or receives a signal.
5785 The rest of the cases are dealt with later on in normal_stop and
5786 print_it_typical. Ideally there should be a call to one of these
5787 print_*_reason functions functions from handle_inferior_event each time
5788 stop_stepping is called. */
5790 /* Print why the inferior has stopped.
5791 We are done with a step/next/si/ni command, print why the inferior has
5792 stopped. For now print nothing. Print a message only if not in the middle
5793 of doing a "step n" operation for n > 1. */
5796 print_end_stepping_range_reason (void)
5798 if ((!inferior_thread ()->step_multi
5799 || !inferior_thread ()->control
.stop_step
)
5800 && ui_out_is_mi_like_p (current_uiout
))
5801 ui_out_field_string (current_uiout
, "reason",
5802 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
5805 /* The inferior was terminated by a signal, print why it stopped. */
5808 print_signal_exited_reason (enum gdb_signal siggnal
)
5810 struct ui_out
*uiout
= current_uiout
;
5812 annotate_signalled ();
5813 if (ui_out_is_mi_like_p (uiout
))
5815 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
5816 ui_out_text (uiout
, "\nProgram terminated with signal ");
5817 annotate_signal_name ();
5818 ui_out_field_string (uiout
, "signal-name",
5819 gdb_signal_to_name (siggnal
));
5820 annotate_signal_name_end ();
5821 ui_out_text (uiout
, ", ");
5822 annotate_signal_string ();
5823 ui_out_field_string (uiout
, "signal-meaning",
5824 gdb_signal_to_string (siggnal
));
5825 annotate_signal_string_end ();
5826 ui_out_text (uiout
, ".\n");
5827 ui_out_text (uiout
, "The program no longer exists.\n");
5830 /* The inferior program is finished, print why it stopped. */
5833 print_exited_reason (int exitstatus
)
5835 struct inferior
*inf
= current_inferior ();
5836 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
5837 struct ui_out
*uiout
= current_uiout
;
5839 annotate_exited (exitstatus
);
5842 if (ui_out_is_mi_like_p (uiout
))
5843 ui_out_field_string (uiout
, "reason",
5844 async_reason_lookup (EXEC_ASYNC_EXITED
));
5845 ui_out_text (uiout
, "[Inferior ");
5846 ui_out_text (uiout
, plongest (inf
->num
));
5847 ui_out_text (uiout
, " (");
5848 ui_out_text (uiout
, pidstr
);
5849 ui_out_text (uiout
, ") exited with code ");
5850 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
5851 ui_out_text (uiout
, "]\n");
5855 if (ui_out_is_mi_like_p (uiout
))
5857 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
5858 ui_out_text (uiout
, "[Inferior ");
5859 ui_out_text (uiout
, plongest (inf
->num
));
5860 ui_out_text (uiout
, " (");
5861 ui_out_text (uiout
, pidstr
);
5862 ui_out_text (uiout
, ") exited normally]\n");
5864 /* Support the --return-child-result option. */
5865 return_child_result_value
= exitstatus
;
5868 /* Signal received, print why the inferior has stopped. The signal table
5869 tells us to print about it. */
5872 print_signal_received_reason (enum gdb_signal siggnal
)
5874 struct ui_out
*uiout
= current_uiout
;
5878 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
5880 struct thread_info
*t
= inferior_thread ();
5882 ui_out_text (uiout
, "\n[");
5883 ui_out_field_string (uiout
, "thread-name",
5884 target_pid_to_str (t
->ptid
));
5885 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
5886 ui_out_text (uiout
, " stopped");
5890 ui_out_text (uiout
, "\nProgram received signal ");
5891 annotate_signal_name ();
5892 if (ui_out_is_mi_like_p (uiout
))
5894 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
5895 ui_out_field_string (uiout
, "signal-name",
5896 gdb_signal_to_name (siggnal
));
5897 annotate_signal_name_end ();
5898 ui_out_text (uiout
, ", ");
5899 annotate_signal_string ();
5900 ui_out_field_string (uiout
, "signal-meaning",
5901 gdb_signal_to_string (siggnal
));
5902 annotate_signal_string_end ();
5904 ui_out_text (uiout
, ".\n");
5907 /* Reverse execution: target ran out of history info, print why the inferior
5911 print_no_history_reason (void)
5913 ui_out_text (current_uiout
, "\nNo more reverse-execution history.\n");
5916 /* Here to return control to GDB when the inferior stops for real.
5917 Print appropriate messages, remove breakpoints, give terminal our modes.
5919 STOP_PRINT_FRAME nonzero means print the executing frame
5920 (pc, function, args, file, line number and line text).
5921 BREAKPOINTS_FAILED nonzero means stop was due to error
5922 attempting to insert breakpoints. */
5927 struct target_waitstatus last
;
5929 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
5931 get_last_target_status (&last_ptid
, &last
);
5933 /* If an exception is thrown from this point on, make sure to
5934 propagate GDB's knowledge of the executing state to the
5935 frontend/user running state. A QUIT is an easy exception to see
5936 here, so do this before any filtered output. */
5938 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
5939 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
5940 && last
.kind
!= TARGET_WAITKIND_EXITED
5941 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
5942 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
5944 /* In non-stop mode, we don't want GDB to switch threads behind the
5945 user's back, to avoid races where the user is typing a command to
5946 apply to thread x, but GDB switches to thread y before the user
5947 finishes entering the command. */
5949 /* As with the notification of thread events, we want to delay
5950 notifying the user that we've switched thread context until
5951 the inferior actually stops.
5953 There's no point in saying anything if the inferior has exited.
5954 Note that SIGNALLED here means "exited with a signal", not
5955 "received a signal". */
5957 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
5958 && target_has_execution
5959 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5960 && last
.kind
!= TARGET_WAITKIND_EXITED
5961 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
5963 target_terminal_ours_for_output ();
5964 printf_filtered (_("[Switching to %s]\n"),
5965 target_pid_to_str (inferior_ptid
));
5966 annotate_thread_changed ();
5967 previous_inferior_ptid
= inferior_ptid
;
5970 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
5972 gdb_assert (sync_execution
|| !target_can_async_p ());
5974 target_terminal_ours_for_output ();
5975 printf_filtered (_("No unwaited-for children left.\n"));
5978 if (!breakpoints_always_inserted_mode () && target_has_execution
)
5980 if (remove_breakpoints ())
5982 target_terminal_ours_for_output ();
5983 printf_filtered (_("Cannot remove breakpoints because "
5984 "program is no longer writable.\nFurther "
5985 "execution is probably impossible.\n"));
5989 /* If an auto-display called a function and that got a signal,
5990 delete that auto-display to avoid an infinite recursion. */
5992 if (stopped_by_random_signal
)
5993 disable_current_display ();
5995 /* Don't print a message if in the middle of doing a "step n"
5996 operation for n > 1 */
5997 if (target_has_execution
5998 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5999 && last
.kind
!= TARGET_WAITKIND_EXITED
6000 && inferior_thread ()->step_multi
6001 && inferior_thread ()->control
.stop_step
)
6004 target_terminal_ours ();
6005 async_enable_stdin ();
6007 /* Set the current source location. This will also happen if we
6008 display the frame below, but the current SAL will be incorrect
6009 during a user hook-stop function. */
6010 if (has_stack_frames () && !stop_stack_dummy
)
6011 set_current_sal_from_frame (get_current_frame (), 1);
6013 /* Let the user/frontend see the threads as stopped. */
6014 do_cleanups (old_chain
);
6016 /* Look up the hook_stop and run it (CLI internally handles problem
6017 of stop_command's pre-hook not existing). */
6019 catch_errors (hook_stop_stub
, stop_command
,
6020 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
6022 if (!has_stack_frames ())
6025 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
6026 || last
.kind
== TARGET_WAITKIND_EXITED
)
6029 /* Select innermost stack frame - i.e., current frame is frame 0,
6030 and current location is based on that.
6031 Don't do this on return from a stack dummy routine,
6032 or if the program has exited. */
6034 if (!stop_stack_dummy
)
6036 select_frame (get_current_frame ());
6038 /* Print current location without a level number, if
6039 we have changed functions or hit a breakpoint.
6040 Print source line if we have one.
6041 bpstat_print() contains the logic deciding in detail
6042 what to print, based on the event(s) that just occurred. */
6044 /* If --batch-silent is enabled then there's no need to print the current
6045 source location, and to try risks causing an error message about
6046 missing source files. */
6047 if (stop_print_frame
&& !batch_silent
)
6051 int do_frame_printing
= 1;
6052 struct thread_info
*tp
= inferior_thread ();
6054 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, last
.kind
);
6058 /* FIXME: cagney/2002-12-01: Given that a frame ID does
6059 (or should) carry around the function and does (or
6060 should) use that when doing a frame comparison. */
6061 if (tp
->control
.stop_step
6062 && frame_id_eq (tp
->control
.step_frame_id
,
6063 get_frame_id (get_current_frame ()))
6064 && step_start_function
== find_pc_function (stop_pc
))
6065 source_flag
= SRC_LINE
; /* Finished step, just
6066 print source line. */
6068 source_flag
= SRC_AND_LOC
; /* Print location and
6071 case PRINT_SRC_AND_LOC
:
6072 source_flag
= SRC_AND_LOC
; /* Print location and
6075 case PRINT_SRC_ONLY
:
6076 source_flag
= SRC_LINE
;
6079 source_flag
= SRC_LINE
; /* something bogus */
6080 do_frame_printing
= 0;
6083 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6086 /* The behavior of this routine with respect to the source
6088 SRC_LINE: Print only source line
6089 LOCATION: Print only location
6090 SRC_AND_LOC: Print location and source line. */
6091 if (do_frame_printing
)
6092 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
6094 /* Display the auto-display expressions. */
6099 /* Save the function value return registers, if we care.
6100 We might be about to restore their previous contents. */
6101 if (inferior_thread ()->control
.proceed_to_finish
6102 && execution_direction
!= EXEC_REVERSE
)
6104 /* This should not be necessary. */
6106 regcache_xfree (stop_registers
);
6108 /* NB: The copy goes through to the target picking up the value of
6109 all the registers. */
6110 stop_registers
= regcache_dup (get_current_regcache ());
6113 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6115 /* Pop the empty frame that contains the stack dummy.
6116 This also restores inferior state prior to the call
6117 (struct infcall_suspend_state). */
6118 struct frame_info
*frame
= get_current_frame ();
6120 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6122 /* frame_pop() calls reinit_frame_cache as the last thing it
6123 does which means there's currently no selected frame. We
6124 don't need to re-establish a selected frame if the dummy call
6125 returns normally, that will be done by
6126 restore_infcall_control_state. However, we do have to handle
6127 the case where the dummy call is returning after being
6128 stopped (e.g. the dummy call previously hit a breakpoint).
6129 We can't know which case we have so just always re-establish
6130 a selected frame here. */
6131 select_frame (get_current_frame ());
6135 annotate_stopped ();
6137 /* Suppress the stop observer if we're in the middle of:
6139 - a step n (n > 1), as there still more steps to be done.
6141 - a "finish" command, as the observer will be called in
6142 finish_command_continuation, so it can include the inferior
6143 function's return value.
6145 - calling an inferior function, as we pretend we inferior didn't
6146 run at all. The return value of the call is handled by the
6147 expression evaluator, through call_function_by_hand. */
6149 if (!target_has_execution
6150 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6151 || last
.kind
== TARGET_WAITKIND_EXITED
6152 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6153 || (!(inferior_thread ()->step_multi
6154 && inferior_thread ()->control
.stop_step
)
6155 && !(inferior_thread ()->control
.stop_bpstat
6156 && inferior_thread ()->control
.proceed_to_finish
)
6157 && !inferior_thread ()->control
.in_infcall
))
6159 if (!ptid_equal (inferior_ptid
, null_ptid
))
6160 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6163 observer_notify_normal_stop (NULL
, stop_print_frame
);
6166 if (target_has_execution
)
6168 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6169 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6170 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6171 Delete any breakpoint that is to be deleted at the next stop. */
6172 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6175 /* Try to get rid of automatically added inferiors that are no
6176 longer needed. Keeping those around slows down things linearly.
6177 Note that this never removes the current inferior. */
6182 hook_stop_stub (void *cmd
)
6184 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6189 signal_stop_state (int signo
)
6191 return signal_stop
[signo
];
6195 signal_print_state (int signo
)
6197 return signal_print
[signo
];
6201 signal_pass_state (int signo
)
6203 return signal_program
[signo
];
6207 signal_cache_update (int signo
)
6211 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6212 signal_cache_update (signo
);
6217 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6218 && signal_print
[signo
] == 0
6219 && signal_program
[signo
] == 1);
6223 signal_stop_update (int signo
, int state
)
6225 int ret
= signal_stop
[signo
];
6227 signal_stop
[signo
] = state
;
6228 signal_cache_update (signo
);
6233 signal_print_update (int signo
, int state
)
6235 int ret
= signal_print
[signo
];
6237 signal_print
[signo
] = state
;
6238 signal_cache_update (signo
);
6243 signal_pass_update (int signo
, int state
)
6245 int ret
= signal_program
[signo
];
6247 signal_program
[signo
] = state
;
6248 signal_cache_update (signo
);
6253 sig_print_header (void)
6255 printf_filtered (_("Signal Stop\tPrint\tPass "
6256 "to program\tDescription\n"));
6260 sig_print_info (enum gdb_signal oursig
)
6262 const char *name
= gdb_signal_to_name (oursig
);
6263 int name_padding
= 13 - strlen (name
);
6265 if (name_padding
<= 0)
6268 printf_filtered ("%s", name
);
6269 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6270 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6271 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6272 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6273 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6276 /* Specify how various signals in the inferior should be handled. */
6279 handle_command (char *args
, int from_tty
)
6282 int digits
, wordlen
;
6283 int sigfirst
, signum
, siglast
;
6284 enum gdb_signal oursig
;
6287 unsigned char *sigs
;
6288 struct cleanup
*old_chain
;
6292 error_no_arg (_("signal to handle"));
6295 /* Allocate and zero an array of flags for which signals to handle. */
6297 nsigs
= (int) GDB_SIGNAL_LAST
;
6298 sigs
= (unsigned char *) alloca (nsigs
);
6299 memset (sigs
, 0, nsigs
);
6301 /* Break the command line up into args. */
6303 argv
= gdb_buildargv (args
);
6304 old_chain
= make_cleanup_freeargv (argv
);
6306 /* Walk through the args, looking for signal oursigs, signal names, and
6307 actions. Signal numbers and signal names may be interspersed with
6308 actions, with the actions being performed for all signals cumulatively
6309 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6311 while (*argv
!= NULL
)
6313 wordlen
= strlen (*argv
);
6314 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6318 sigfirst
= siglast
= -1;
6320 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6322 /* Apply action to all signals except those used by the
6323 debugger. Silently skip those. */
6326 siglast
= nsigs
- 1;
6328 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6330 SET_SIGS (nsigs
, sigs
, signal_stop
);
6331 SET_SIGS (nsigs
, sigs
, signal_print
);
6333 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6335 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6337 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6339 SET_SIGS (nsigs
, sigs
, signal_print
);
6341 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6343 SET_SIGS (nsigs
, sigs
, signal_program
);
6345 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6347 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6349 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6351 SET_SIGS (nsigs
, sigs
, signal_program
);
6353 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6355 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6356 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6358 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6360 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6362 else if (digits
> 0)
6364 /* It is numeric. The numeric signal refers to our own
6365 internal signal numbering from target.h, not to host/target
6366 signal number. This is a feature; users really should be
6367 using symbolic names anyway, and the common ones like
6368 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6370 sigfirst
= siglast
= (int)
6371 gdb_signal_from_command (atoi (*argv
));
6372 if ((*argv
)[digits
] == '-')
6375 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6377 if (sigfirst
> siglast
)
6379 /* Bet he didn't figure we'd think of this case... */
6387 oursig
= gdb_signal_from_name (*argv
);
6388 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
6390 sigfirst
= siglast
= (int) oursig
;
6394 /* Not a number and not a recognized flag word => complain. */
6395 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6399 /* If any signal numbers or symbol names were found, set flags for
6400 which signals to apply actions to. */
6402 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6404 switch ((enum gdb_signal
) signum
)
6406 case GDB_SIGNAL_TRAP
:
6407 case GDB_SIGNAL_INT
:
6408 if (!allsigs
&& !sigs
[signum
])
6410 if (query (_("%s is used by the debugger.\n\
6411 Are you sure you want to change it? "),
6412 gdb_signal_to_name ((enum gdb_signal
) signum
)))
6418 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6419 gdb_flush (gdb_stdout
);
6424 case GDB_SIGNAL_DEFAULT
:
6425 case GDB_SIGNAL_UNKNOWN
:
6426 /* Make sure that "all" doesn't print these. */
6437 for (signum
= 0; signum
< nsigs
; signum
++)
6440 signal_cache_update (-1);
6441 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6442 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
6446 /* Show the results. */
6447 sig_print_header ();
6448 for (; signum
< nsigs
; signum
++)
6450 sig_print_info (signum
);
6456 do_cleanups (old_chain
);
6460 xdb_handle_command (char *args
, int from_tty
)
6463 struct cleanup
*old_chain
;
6466 error_no_arg (_("xdb command"));
6468 /* Break the command line up into args. */
6470 argv
= gdb_buildargv (args
);
6471 old_chain
= make_cleanup_freeargv (argv
);
6472 if (argv
[1] != (char *) NULL
)
6477 bufLen
= strlen (argv
[0]) + 20;
6478 argBuf
= (char *) xmalloc (bufLen
);
6482 enum gdb_signal oursig
;
6484 oursig
= gdb_signal_from_name (argv
[0]);
6485 memset (argBuf
, 0, bufLen
);
6486 if (strcmp (argv
[1], "Q") == 0)
6487 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6490 if (strcmp (argv
[1], "s") == 0)
6492 if (!signal_stop
[oursig
])
6493 sprintf (argBuf
, "%s %s", argv
[0], "stop");
6495 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
6497 else if (strcmp (argv
[1], "i") == 0)
6499 if (!signal_program
[oursig
])
6500 sprintf (argBuf
, "%s %s", argv
[0], "pass");
6502 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
6504 else if (strcmp (argv
[1], "r") == 0)
6506 if (!signal_print
[oursig
])
6507 sprintf (argBuf
, "%s %s", argv
[0], "print");
6509 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6515 handle_command (argBuf
, from_tty
);
6517 printf_filtered (_("Invalid signal handling flag.\n"));
6522 do_cleanups (old_chain
);
6526 gdb_signal_from_command (int num
)
6528 if (num
>= 1 && num
<= 15)
6529 return (enum gdb_signal
) num
;
6530 error (_("Only signals 1-15 are valid as numeric signals.\n\
6531 Use \"info signals\" for a list of symbolic signals."));
6534 /* Print current contents of the tables set by the handle command.
6535 It is possible we should just be printing signals actually used
6536 by the current target (but for things to work right when switching
6537 targets, all signals should be in the signal tables). */
6540 signals_info (char *signum_exp
, int from_tty
)
6542 enum gdb_signal oursig
;
6544 sig_print_header ();
6548 /* First see if this is a symbol name. */
6549 oursig
= gdb_signal_from_name (signum_exp
);
6550 if (oursig
== GDB_SIGNAL_UNKNOWN
)
6552 /* No, try numeric. */
6554 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
6556 sig_print_info (oursig
);
6560 printf_filtered ("\n");
6561 /* These ugly casts brought to you by the native VAX compiler. */
6562 for (oursig
= GDB_SIGNAL_FIRST
;
6563 (int) oursig
< (int) GDB_SIGNAL_LAST
;
6564 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
6568 if (oursig
!= GDB_SIGNAL_UNKNOWN
6569 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
6570 sig_print_info (oursig
);
6573 printf_filtered (_("\nUse the \"handle\" command "
6574 "to change these tables.\n"));
6577 /* Check if it makes sense to read $_siginfo from the current thread
6578 at this point. If not, throw an error. */
6581 validate_siginfo_access (void)
6583 /* No current inferior, no siginfo. */
6584 if (ptid_equal (inferior_ptid
, null_ptid
))
6585 error (_("No thread selected."));
6587 /* Don't try to read from a dead thread. */
6588 if (is_exited (inferior_ptid
))
6589 error (_("The current thread has terminated"));
6591 /* ... or from a spinning thread. */
6592 if (is_running (inferior_ptid
))
6593 error (_("Selected thread is running."));
6596 /* The $_siginfo convenience variable is a bit special. We don't know
6597 for sure the type of the value until we actually have a chance to
6598 fetch the data. The type can change depending on gdbarch, so it is
6599 also dependent on which thread you have selected.
6601 1. making $_siginfo be an internalvar that creates a new value on
6604 2. making the value of $_siginfo be an lval_computed value. */
6606 /* This function implements the lval_computed support for reading a
6610 siginfo_value_read (struct value
*v
)
6612 LONGEST transferred
;
6614 validate_siginfo_access ();
6617 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
6619 value_contents_all_raw (v
),
6621 TYPE_LENGTH (value_type (v
)));
6623 if (transferred
!= TYPE_LENGTH (value_type (v
)))
6624 error (_("Unable to read siginfo"));
6627 /* This function implements the lval_computed support for writing a
6631 siginfo_value_write (struct value
*v
, struct value
*fromval
)
6633 LONGEST transferred
;
6635 validate_siginfo_access ();
6637 transferred
= target_write (¤t_target
,
6638 TARGET_OBJECT_SIGNAL_INFO
,
6640 value_contents_all_raw (fromval
),
6642 TYPE_LENGTH (value_type (fromval
)));
6644 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
6645 error (_("Unable to write siginfo"));
6648 static const struct lval_funcs siginfo_value_funcs
=
6654 /* Return a new value with the correct type for the siginfo object of
6655 the current thread using architecture GDBARCH. Return a void value
6656 if there's no object available. */
6658 static struct value
*
6659 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
6662 if (target_has_stack
6663 && !ptid_equal (inferior_ptid
, null_ptid
)
6664 && gdbarch_get_siginfo_type_p (gdbarch
))
6666 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6668 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
6671 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
6675 /* infcall_suspend_state contains state about the program itself like its
6676 registers and any signal it received when it last stopped.
6677 This state must be restored regardless of how the inferior function call
6678 ends (either successfully, or after it hits a breakpoint or signal)
6679 if the program is to properly continue where it left off. */
6681 struct infcall_suspend_state
6683 struct thread_suspend_state thread_suspend
;
6684 struct inferior_suspend_state inferior_suspend
;
6688 struct regcache
*registers
;
6690 /* Format of SIGINFO_DATA or NULL if it is not present. */
6691 struct gdbarch
*siginfo_gdbarch
;
6693 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
6694 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
6695 content would be invalid. */
6696 gdb_byte
*siginfo_data
;
6699 struct infcall_suspend_state
*
6700 save_infcall_suspend_state (void)
6702 struct infcall_suspend_state
*inf_state
;
6703 struct thread_info
*tp
= inferior_thread ();
6704 struct inferior
*inf
= current_inferior ();
6705 struct regcache
*regcache
= get_current_regcache ();
6706 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6707 gdb_byte
*siginfo_data
= NULL
;
6709 if (gdbarch_get_siginfo_type_p (gdbarch
))
6711 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6712 size_t len
= TYPE_LENGTH (type
);
6713 struct cleanup
*back_to
;
6715 siginfo_data
= xmalloc (len
);
6716 back_to
= make_cleanup (xfree
, siginfo_data
);
6718 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6719 siginfo_data
, 0, len
) == len
)
6720 discard_cleanups (back_to
);
6723 /* Errors ignored. */
6724 do_cleanups (back_to
);
6725 siginfo_data
= NULL
;
6729 inf_state
= XZALLOC (struct infcall_suspend_state
);
6733 inf_state
->siginfo_gdbarch
= gdbarch
;
6734 inf_state
->siginfo_data
= siginfo_data
;
6737 inf_state
->thread_suspend
= tp
->suspend
;
6738 inf_state
->inferior_suspend
= inf
->suspend
;
6740 /* run_inferior_call will not use the signal due to its `proceed' call with
6741 GDB_SIGNAL_0 anyway. */
6742 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6744 inf_state
->stop_pc
= stop_pc
;
6746 inf_state
->registers
= regcache_dup (regcache
);
6751 /* Restore inferior session state to INF_STATE. */
6754 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6756 struct thread_info
*tp
= inferior_thread ();
6757 struct inferior
*inf
= current_inferior ();
6758 struct regcache
*regcache
= get_current_regcache ();
6759 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6761 tp
->suspend
= inf_state
->thread_suspend
;
6762 inf
->suspend
= inf_state
->inferior_suspend
;
6764 stop_pc
= inf_state
->stop_pc
;
6766 if (inf_state
->siginfo_gdbarch
== gdbarch
)
6768 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6769 size_t len
= TYPE_LENGTH (type
);
6771 /* Errors ignored. */
6772 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6773 inf_state
->siginfo_data
, 0, len
);
6776 /* The inferior can be gone if the user types "print exit(0)"
6777 (and perhaps other times). */
6778 if (target_has_execution
)
6779 /* NB: The register write goes through to the target. */
6780 regcache_cpy (regcache
, inf_state
->registers
);
6782 discard_infcall_suspend_state (inf_state
);
6786 do_restore_infcall_suspend_state_cleanup (void *state
)
6788 restore_infcall_suspend_state (state
);
6792 make_cleanup_restore_infcall_suspend_state
6793 (struct infcall_suspend_state
*inf_state
)
6795 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
6799 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6801 regcache_xfree (inf_state
->registers
);
6802 xfree (inf_state
->siginfo_data
);
6807 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
6809 return inf_state
->registers
;
6812 /* infcall_control_state contains state regarding gdb's control of the
6813 inferior itself like stepping control. It also contains session state like
6814 the user's currently selected frame. */
6816 struct infcall_control_state
6818 struct thread_control_state thread_control
;
6819 struct inferior_control_state inferior_control
;
6822 enum stop_stack_kind stop_stack_dummy
;
6823 int stopped_by_random_signal
;
6824 int stop_after_trap
;
6826 /* ID if the selected frame when the inferior function call was made. */
6827 struct frame_id selected_frame_id
;
6830 /* Save all of the information associated with the inferior<==>gdb
6833 struct infcall_control_state
*
6834 save_infcall_control_state (void)
6836 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
6837 struct thread_info
*tp
= inferior_thread ();
6838 struct inferior
*inf
= current_inferior ();
6840 inf_status
->thread_control
= tp
->control
;
6841 inf_status
->inferior_control
= inf
->control
;
6843 tp
->control
.step_resume_breakpoint
= NULL
;
6844 tp
->control
.exception_resume_breakpoint
= NULL
;
6846 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
6847 chain. If caller's caller is walking the chain, they'll be happier if we
6848 hand them back the original chain when restore_infcall_control_state is
6850 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
6853 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
6854 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
6855 inf_status
->stop_after_trap
= stop_after_trap
;
6857 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
6863 restore_selected_frame (void *args
)
6865 struct frame_id
*fid
= (struct frame_id
*) args
;
6866 struct frame_info
*frame
;
6868 frame
= frame_find_by_id (*fid
);
6870 /* If inf_status->selected_frame_id is NULL, there was no previously
6874 warning (_("Unable to restore previously selected frame."));
6878 select_frame (frame
);
6883 /* Restore inferior session state to INF_STATUS. */
6886 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
6888 struct thread_info
*tp
= inferior_thread ();
6889 struct inferior
*inf
= current_inferior ();
6891 if (tp
->control
.step_resume_breakpoint
)
6892 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
6894 if (tp
->control
.exception_resume_breakpoint
)
6895 tp
->control
.exception_resume_breakpoint
->disposition
6896 = disp_del_at_next_stop
;
6898 /* Handle the bpstat_copy of the chain. */
6899 bpstat_clear (&tp
->control
.stop_bpstat
);
6901 tp
->control
= inf_status
->thread_control
;
6902 inf
->control
= inf_status
->inferior_control
;
6905 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
6906 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
6907 stop_after_trap
= inf_status
->stop_after_trap
;
6909 if (target_has_stack
)
6911 /* The point of catch_errors is that if the stack is clobbered,
6912 walking the stack might encounter a garbage pointer and
6913 error() trying to dereference it. */
6915 (restore_selected_frame
, &inf_status
->selected_frame_id
,
6916 "Unable to restore previously selected frame:\n",
6917 RETURN_MASK_ERROR
) == 0)
6918 /* Error in restoring the selected frame. Select the innermost
6920 select_frame (get_current_frame ());
6927 do_restore_infcall_control_state_cleanup (void *sts
)
6929 restore_infcall_control_state (sts
);
6933 make_cleanup_restore_infcall_control_state
6934 (struct infcall_control_state
*inf_status
)
6936 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
6940 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
6942 if (inf_status
->thread_control
.step_resume_breakpoint
)
6943 inf_status
->thread_control
.step_resume_breakpoint
->disposition
6944 = disp_del_at_next_stop
;
6946 if (inf_status
->thread_control
.exception_resume_breakpoint
)
6947 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
6948 = disp_del_at_next_stop
;
6950 /* See save_infcall_control_state for info on stop_bpstat. */
6951 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
6957 ptid_match (ptid_t ptid
, ptid_t filter
)
6959 if (ptid_equal (filter
, minus_one_ptid
))
6961 if (ptid_is_pid (filter
)
6962 && ptid_get_pid (ptid
) == ptid_get_pid (filter
))
6964 else if (ptid_equal (ptid
, filter
))
6970 /* restore_inferior_ptid() will be used by the cleanup machinery
6971 to restore the inferior_ptid value saved in a call to
6972 save_inferior_ptid(). */
6975 restore_inferior_ptid (void *arg
)
6977 ptid_t
*saved_ptid_ptr
= arg
;
6979 inferior_ptid
= *saved_ptid_ptr
;
6983 /* Save the value of inferior_ptid so that it may be restored by a
6984 later call to do_cleanups(). Returns the struct cleanup pointer
6985 needed for later doing the cleanup. */
6988 save_inferior_ptid (void)
6990 ptid_t
*saved_ptid_ptr
;
6992 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
6993 *saved_ptid_ptr
= inferior_ptid
;
6994 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
6998 /* User interface for reverse debugging:
6999 Set exec-direction / show exec-direction commands
7000 (returns error unless target implements to_set_exec_direction method). */
7002 int execution_direction
= EXEC_FORWARD
;
7003 static const char exec_forward
[] = "forward";
7004 static const char exec_reverse
[] = "reverse";
7005 static const char *exec_direction
= exec_forward
;
7006 static const char *const exec_direction_names
[] = {
7013 set_exec_direction_func (char *args
, int from_tty
,
7014 struct cmd_list_element
*cmd
)
7016 if (target_can_execute_reverse
)
7018 if (!strcmp (exec_direction
, exec_forward
))
7019 execution_direction
= EXEC_FORWARD
;
7020 else if (!strcmp (exec_direction
, exec_reverse
))
7021 execution_direction
= EXEC_REVERSE
;
7025 exec_direction
= exec_forward
;
7026 error (_("Target does not support this operation."));
7031 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7032 struct cmd_list_element
*cmd
, const char *value
)
7034 switch (execution_direction
) {
7036 fprintf_filtered (out
, _("Forward.\n"));
7039 fprintf_filtered (out
, _("Reverse.\n"));
7042 internal_error (__FILE__
, __LINE__
,
7043 _("bogus execution_direction value: %d"),
7044 (int) execution_direction
);
7048 /* User interface for non-stop mode. */
7053 set_non_stop (char *args
, int from_tty
,
7054 struct cmd_list_element
*c
)
7056 if (target_has_execution
)
7058 non_stop_1
= non_stop
;
7059 error (_("Cannot change this setting while the inferior is running."));
7062 non_stop
= non_stop_1
;
7066 show_non_stop (struct ui_file
*file
, int from_tty
,
7067 struct cmd_list_element
*c
, const char *value
)
7069 fprintf_filtered (file
,
7070 _("Controlling the inferior in non-stop mode is %s.\n"),
7075 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7076 struct cmd_list_element
*c
, const char *value
)
7078 fprintf_filtered (file
, _("Resuming the execution of threads "
7079 "of all processes is %s.\n"), value
);
7082 /* Implementation of `siginfo' variable. */
7084 static const struct internalvar_funcs siginfo_funcs
=
7092 _initialize_infrun (void)
7097 add_info ("signals", signals_info
, _("\
7098 What debugger does when program gets various signals.\n\
7099 Specify a signal as argument to print info on that signal only."));
7100 add_info_alias ("handle", "signals", 0);
7102 add_com ("handle", class_run
, handle_command
, _("\
7103 Specify how to handle a signal.\n\
7104 Args are signals and actions to apply to those signals.\n\
7105 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7106 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7107 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7108 The special arg \"all\" is recognized to mean all signals except those\n\
7109 used by the debugger, typically SIGTRAP and SIGINT.\n\
7110 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7111 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7112 Stop means reenter debugger if this signal happens (implies print).\n\
7113 Print means print a message if this signal happens.\n\
7114 Pass means let program see this signal; otherwise program doesn't know.\n\
7115 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7116 Pass and Stop may be combined."));
7119 add_com ("lz", class_info
, signals_info
, _("\
7120 What debugger does when program gets various signals.\n\
7121 Specify a signal as argument to print info on that signal only."));
7122 add_com ("z", class_run
, xdb_handle_command
, _("\
7123 Specify how to handle a signal.\n\
7124 Args are signals and actions to apply to those signals.\n\
7125 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7126 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7127 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7128 The special arg \"all\" is recognized to mean all signals except those\n\
7129 used by the debugger, typically SIGTRAP and SIGINT.\n\
7130 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7131 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7132 nopass), \"Q\" (noprint)\n\
7133 Stop means reenter debugger if this signal happens (implies print).\n\
7134 Print means print a message if this signal happens.\n\
7135 Pass means let program see this signal; otherwise program doesn't know.\n\
7136 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7137 Pass and Stop may be combined."));
7141 stop_command
= add_cmd ("stop", class_obscure
,
7142 not_just_help_class_command
, _("\
7143 There is no `stop' command, but you can set a hook on `stop'.\n\
7144 This allows you to set a list of commands to be run each time execution\n\
7145 of the program stops."), &cmdlist
);
7147 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7148 Set inferior debugging."), _("\
7149 Show inferior debugging."), _("\
7150 When non-zero, inferior specific debugging is enabled."),
7153 &setdebuglist
, &showdebuglist
);
7155 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7156 &debug_displaced
, _("\
7157 Set displaced stepping debugging."), _("\
7158 Show displaced stepping debugging."), _("\
7159 When non-zero, displaced stepping specific debugging is enabled."),
7161 show_debug_displaced
,
7162 &setdebuglist
, &showdebuglist
);
7164 add_setshow_boolean_cmd ("non-stop", no_class
,
7166 Set whether gdb controls the inferior in non-stop mode."), _("\
7167 Show whether gdb controls the inferior in non-stop mode."), _("\
7168 When debugging a multi-threaded program and this setting is\n\
7169 off (the default, also called all-stop mode), when one thread stops\n\
7170 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7171 all other threads in the program while you interact with the thread of\n\
7172 interest. When you continue or step a thread, you can allow the other\n\
7173 threads to run, or have them remain stopped, but while you inspect any\n\
7174 thread's state, all threads stop.\n\
7176 In non-stop mode, when one thread stops, other threads can continue\n\
7177 to run freely. You'll be able to step each thread independently,\n\
7178 leave it stopped or free to run as needed."),
7184 numsigs
= (int) GDB_SIGNAL_LAST
;
7185 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7186 signal_print
= (unsigned char *)
7187 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7188 signal_program
= (unsigned char *)
7189 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7190 signal_pass
= (unsigned char *)
7191 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7192 for (i
= 0; i
< numsigs
; i
++)
7195 signal_print
[i
] = 1;
7196 signal_program
[i
] = 1;
7199 /* Signals caused by debugger's own actions
7200 should not be given to the program afterwards. */
7201 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7202 signal_program
[GDB_SIGNAL_INT
] = 0;
7204 /* Signals that are not errors should not normally enter the debugger. */
7205 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7206 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7207 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7208 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7209 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7210 signal_print
[GDB_SIGNAL_PROF
] = 0;
7211 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7212 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7213 signal_stop
[GDB_SIGNAL_IO
] = 0;
7214 signal_print
[GDB_SIGNAL_IO
] = 0;
7215 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7216 signal_print
[GDB_SIGNAL_POLL
] = 0;
7217 signal_stop
[GDB_SIGNAL_URG
] = 0;
7218 signal_print
[GDB_SIGNAL_URG
] = 0;
7219 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7220 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7221 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7222 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7224 /* These signals are used internally by user-level thread
7225 implementations. (See signal(5) on Solaris.) Like the above
7226 signals, a healthy program receives and handles them as part of
7227 its normal operation. */
7228 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7229 signal_print
[GDB_SIGNAL_LWP
] = 0;
7230 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7231 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7232 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7233 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7235 /* Update cached state. */
7236 signal_cache_update (-1);
7238 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7239 &stop_on_solib_events
, _("\
7240 Set stopping for shared library events."), _("\
7241 Show stopping for shared library events."), _("\
7242 If nonzero, gdb will give control to the user when the dynamic linker\n\
7243 notifies gdb of shared library events. The most common event of interest\n\
7244 to the user would be loading/unloading of a new library."),
7246 show_stop_on_solib_events
,
7247 &setlist
, &showlist
);
7249 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7250 follow_fork_mode_kind_names
,
7251 &follow_fork_mode_string
, _("\
7252 Set debugger response to a program call of fork or vfork."), _("\
7253 Show debugger response to a program call of fork or vfork."), _("\
7254 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7255 parent - the original process is debugged after a fork\n\
7256 child - the new process is debugged after a fork\n\
7257 The unfollowed process will continue to run.\n\
7258 By default, the debugger will follow the parent process."),
7260 show_follow_fork_mode_string
,
7261 &setlist
, &showlist
);
7263 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7264 follow_exec_mode_names
,
7265 &follow_exec_mode_string
, _("\
7266 Set debugger response to a program call of exec."), _("\
7267 Show debugger response to a program call of exec."), _("\
7268 An exec call replaces the program image of a process.\n\
7270 follow-exec-mode can be:\n\
7272 new - the debugger creates a new inferior and rebinds the process\n\
7273 to this new inferior. The program the process was running before\n\
7274 the exec call can be restarted afterwards by restarting the original\n\
7277 same - the debugger keeps the process bound to the same inferior.\n\
7278 The new executable image replaces the previous executable loaded in\n\
7279 the inferior. Restarting the inferior after the exec call restarts\n\
7280 the executable the process was running after the exec call.\n\
7282 By default, the debugger will use the same inferior."),
7284 show_follow_exec_mode_string
,
7285 &setlist
, &showlist
);
7287 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7288 scheduler_enums
, &scheduler_mode
, _("\
7289 Set mode for locking scheduler during execution."), _("\
7290 Show mode for locking scheduler during execution."), _("\
7291 off == no locking (threads may preempt at any time)\n\
7292 on == full locking (no thread except the current thread may run)\n\
7293 step == scheduler locked during every single-step operation.\n\
7294 In this mode, no other thread may run during a step command.\n\
7295 Other threads may run while stepping over a function call ('next')."),
7296 set_schedlock_func
, /* traps on target vector */
7297 show_scheduler_mode
,
7298 &setlist
, &showlist
);
7300 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7301 Set mode for resuming threads of all processes."), _("\
7302 Show mode for resuming threads of all processes."), _("\
7303 When on, execution commands (such as 'continue' or 'next') resume all\n\
7304 threads of all processes. When off (which is the default), execution\n\
7305 commands only resume the threads of the current process. The set of\n\
7306 threads that are resumed is further refined by the scheduler-locking\n\
7307 mode (see help set scheduler-locking)."),
7309 show_schedule_multiple
,
7310 &setlist
, &showlist
);
7312 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7313 Set mode of the step operation."), _("\
7314 Show mode of the step operation."), _("\
7315 When set, doing a step over a function without debug line information\n\
7316 will stop at the first instruction of that function. Otherwise, the\n\
7317 function is skipped and the step command stops at a different source line."),
7319 show_step_stop_if_no_debug
,
7320 &setlist
, &showlist
);
7322 add_setshow_enum_cmd ("displaced-stepping", class_run
,
7323 can_use_displaced_stepping_enum
,
7324 &can_use_displaced_stepping
, _("\
7325 Set debugger's willingness to use displaced stepping."), _("\
7326 Show debugger's willingness to use displaced stepping."), _("\
7327 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7328 supported by the target architecture. If off, gdb will not use displaced\n\
7329 stepping to step over breakpoints, even if such is supported by the target\n\
7330 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7331 if the target architecture supports it and non-stop mode is active, but will not\n\
7332 use it in all-stop mode (see help set non-stop)."),
7334 show_can_use_displaced_stepping
,
7335 &setlist
, &showlist
);
7337 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7338 &exec_direction
, _("Set direction of execution.\n\
7339 Options are 'forward' or 'reverse'."),
7340 _("Show direction of execution (forward/reverse)."),
7341 _("Tells gdb whether to execute forward or backward."),
7342 set_exec_direction_func
, show_exec_direction_func
,
7343 &setlist
, &showlist
);
7345 /* Set/show detach-on-fork: user-settable mode. */
7347 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7348 Set whether gdb will detach the child of a fork."), _("\
7349 Show whether gdb will detach the child of a fork."), _("\
7350 Tells gdb whether to detach the child of a fork."),
7351 NULL
, NULL
, &setlist
, &showlist
);
7353 /* Set/show disable address space randomization mode. */
7355 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7356 &disable_randomization
, _("\
7357 Set disabling of debuggee's virtual address space randomization."), _("\
7358 Show disabling of debuggee's virtual address space randomization."), _("\
7359 When this mode is on (which is the default), randomization of the virtual\n\
7360 address space is disabled. Standalone programs run with the randomization\n\
7361 enabled by default on some platforms."),
7362 &set_disable_randomization
,
7363 &show_disable_randomization
,
7364 &setlist
, &showlist
);
7366 /* ptid initializations */
7367 inferior_ptid
= null_ptid
;
7368 target_last_wait_ptid
= minus_one_ptid
;
7370 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7371 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7372 observer_attach_thread_exit (infrun_thread_thread_exit
);
7373 observer_attach_inferior_exit (infrun_inferior_exit
);
7375 /* Explicitly create without lookup, since that tries to create a
7376 value with a void typed value, and when we get here, gdbarch
7377 isn't initialized yet. At this point, we're quite sure there
7378 isn't another convenience variable of the same name. */
7379 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7381 add_setshow_boolean_cmd ("observer", no_class
,
7382 &observer_mode_1
, _("\
7383 Set whether gdb controls the inferior in observer mode."), _("\
7384 Show whether gdb controls the inferior in observer mode."), _("\
7385 In observer mode, GDB can get data from the inferior, but not\n\
7386 affect its execution. Registers and memory may not be changed,\n\
7387 breakpoints may not be set, and the program cannot be interrupted\n\