1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2014 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/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 /* Prototypes for local functions */
66 static void signals_info (char *, int);
68 static void handle_command (char *, int);
70 static void sig_print_info (enum gdb_signal
);
72 static void sig_print_header (void);
74 static void resume_cleanups (void *);
76 static int hook_stop_stub (void *);
78 static int restore_selected_frame (void *);
80 static int follow_fork (void);
82 static int follow_fork_inferior (int follow_child
, int detach_fork
);
84 static void follow_inferior_reset_breakpoints (void);
86 static void set_schedlock_func (char *args
, int from_tty
,
87 struct cmd_list_element
*c
);
89 static int currently_stepping (struct thread_info
*tp
);
91 static void xdb_handle_command (char *args
, int from_tty
);
93 void _initialize_infrun (void);
95 void nullify_last_target_wait_ptid (void);
97 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
99 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
101 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
103 /* When set, stop the 'step' command if we enter a function which has
104 no line number information. The normal behavior is that we step
105 over such function. */
106 int step_stop_if_no_debug
= 0;
108 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
109 struct cmd_list_element
*c
, const char *value
)
111 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
114 /* In asynchronous mode, but simulating synchronous execution. */
116 int sync_execution
= 0;
118 /* proceed and normal_stop use this to notify the user when the
119 inferior stopped in a different thread than it had been running
122 static ptid_t previous_inferior_ptid
;
124 /* If set (default for legacy reasons), when following a fork, GDB
125 will detach from one of the fork branches, child or parent.
126 Exactly which branch is detached depends on 'set follow-fork-mode'
129 static int detach_fork
= 1;
131 int debug_displaced
= 0;
133 show_debug_displaced (struct ui_file
*file
, int from_tty
,
134 struct cmd_list_element
*c
, const char *value
)
136 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
139 unsigned int debug_infrun
= 0;
141 show_debug_infrun (struct ui_file
*file
, int from_tty
,
142 struct cmd_list_element
*c
, const char *value
)
144 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
148 /* Support for disabling address space randomization. */
150 int disable_randomization
= 1;
153 show_disable_randomization (struct ui_file
*file
, int from_tty
,
154 struct cmd_list_element
*c
, const char *value
)
156 if (target_supports_disable_randomization ())
157 fprintf_filtered (file
,
158 _("Disabling randomization of debuggee's "
159 "virtual address space is %s.\n"),
162 fputs_filtered (_("Disabling randomization of debuggee's "
163 "virtual address space is unsupported on\n"
164 "this platform.\n"), file
);
168 set_disable_randomization (char *args
, int from_tty
,
169 struct cmd_list_element
*c
)
171 if (!target_supports_disable_randomization ())
172 error (_("Disabling randomization of debuggee's "
173 "virtual address space is unsupported on\n"
177 /* User interface for non-stop mode. */
180 static int non_stop_1
= 0;
183 set_non_stop (char *args
, int from_tty
,
184 struct cmd_list_element
*c
)
186 if (target_has_execution
)
188 non_stop_1
= non_stop
;
189 error (_("Cannot change this setting while the inferior is running."));
192 non_stop
= non_stop_1
;
196 show_non_stop (struct ui_file
*file
, int from_tty
,
197 struct cmd_list_element
*c
, const char *value
)
199 fprintf_filtered (file
,
200 _("Controlling the inferior in non-stop mode is %s.\n"),
204 /* "Observer mode" is somewhat like a more extreme version of
205 non-stop, in which all GDB operations that might affect the
206 target's execution have been disabled. */
208 int observer_mode
= 0;
209 static int observer_mode_1
= 0;
212 set_observer_mode (char *args
, int from_tty
,
213 struct cmd_list_element
*c
)
215 if (target_has_execution
)
217 observer_mode_1
= observer_mode
;
218 error (_("Cannot change this setting while the inferior is running."));
221 observer_mode
= observer_mode_1
;
223 may_write_registers
= !observer_mode
;
224 may_write_memory
= !observer_mode
;
225 may_insert_breakpoints
= !observer_mode
;
226 may_insert_tracepoints
= !observer_mode
;
227 /* We can insert fast tracepoints in or out of observer mode,
228 but enable them if we're going into this mode. */
230 may_insert_fast_tracepoints
= 1;
231 may_stop
= !observer_mode
;
232 update_target_permissions ();
234 /* Going *into* observer mode we must force non-stop, then
235 going out we leave it that way. */
238 pagination_enabled
= 0;
239 non_stop
= non_stop_1
= 1;
243 printf_filtered (_("Observer mode is now %s.\n"),
244 (observer_mode
? "on" : "off"));
248 show_observer_mode (struct ui_file
*file
, int from_tty
,
249 struct cmd_list_element
*c
, const char *value
)
251 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
254 /* This updates the value of observer mode based on changes in
255 permissions. Note that we are deliberately ignoring the values of
256 may-write-registers and may-write-memory, since the user may have
257 reason to enable these during a session, for instance to turn on a
258 debugging-related global. */
261 update_observer_mode (void)
265 newval
= (!may_insert_breakpoints
266 && !may_insert_tracepoints
267 && may_insert_fast_tracepoints
271 /* Let the user know if things change. */
272 if (newval
!= observer_mode
)
273 printf_filtered (_("Observer mode is now %s.\n"),
274 (newval
? "on" : "off"));
276 observer_mode
= observer_mode_1
= newval
;
279 /* Tables of how to react to signals; the user sets them. */
281 static unsigned char *signal_stop
;
282 static unsigned char *signal_print
;
283 static unsigned char *signal_program
;
285 /* Table of signals that are registered with "catch signal". A
286 non-zero entry indicates that the signal is caught by some "catch
287 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
289 static unsigned char *signal_catch
;
291 /* Table of signals that the target may silently handle.
292 This is automatically determined from the flags above,
293 and simply cached here. */
294 static unsigned char *signal_pass
;
296 #define SET_SIGS(nsigs,sigs,flags) \
298 int signum = (nsigs); \
299 while (signum-- > 0) \
300 if ((sigs)[signum]) \
301 (flags)[signum] = 1; \
304 #define UNSET_SIGS(nsigs,sigs,flags) \
306 int signum = (nsigs); \
307 while (signum-- > 0) \
308 if ((sigs)[signum]) \
309 (flags)[signum] = 0; \
312 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
313 this function is to avoid exporting `signal_program'. */
316 update_signals_program_target (void)
318 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
321 /* Value to pass to target_resume() to cause all threads to resume. */
323 #define RESUME_ALL minus_one_ptid
325 /* Command list pointer for the "stop" placeholder. */
327 static struct cmd_list_element
*stop_command
;
329 /* Function inferior was in as of last step command. */
331 static struct symbol
*step_start_function
;
333 /* Nonzero if we want to give control to the user when we're notified
334 of shared library events by the dynamic linker. */
335 int stop_on_solib_events
;
337 /* Enable or disable optional shared library event breakpoints
338 as appropriate when the above flag is changed. */
341 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
343 update_solib_breakpoints ();
347 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
348 struct cmd_list_element
*c
, const char *value
)
350 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
354 /* Nonzero means expecting a trace trap
355 and should stop the inferior and return silently when it happens. */
359 /* Save register contents here when executing a "finish" command or are
360 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
361 Thus this contains the return value from the called function (assuming
362 values are returned in a register). */
364 struct regcache
*stop_registers
;
366 /* Nonzero after stop if current stack frame should be printed. */
368 static int stop_print_frame
;
370 /* This is a cached copy of the pid/waitstatus of the last event
371 returned by target_wait()/deprecated_target_wait_hook(). This
372 information is returned by get_last_target_status(). */
373 static ptid_t target_last_wait_ptid
;
374 static struct target_waitstatus target_last_waitstatus
;
376 static void context_switch (ptid_t ptid
);
378 void init_thread_stepping_state (struct thread_info
*tss
);
380 static const char follow_fork_mode_child
[] = "child";
381 static const char follow_fork_mode_parent
[] = "parent";
383 static const char *const follow_fork_mode_kind_names
[] = {
384 follow_fork_mode_child
,
385 follow_fork_mode_parent
,
389 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
391 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
392 struct cmd_list_element
*c
, const char *value
)
394 fprintf_filtered (file
,
395 _("Debugger response to a program "
396 "call of fork or vfork is \"%s\".\n"),
401 /* Handle changes to the inferior list based on the type of fork,
402 which process is being followed, and whether the other process
403 should be detached. On entry inferior_ptid must be the ptid of
404 the fork parent. At return inferior_ptid is the ptid of the
405 followed inferior. */
408 follow_fork_inferior (int follow_child
, int detach_fork
)
411 int parent_pid
, child_pid
;
413 has_vforked
= (inferior_thread ()->pending_follow
.kind
414 == TARGET_WAITKIND_VFORKED
);
415 parent_pid
= ptid_get_lwp (inferior_ptid
);
417 parent_pid
= ptid_get_pid (inferior_ptid
);
419 = ptid_get_pid (inferior_thread ()->pending_follow
.value
.related_pid
);
422 && !non_stop
/* Non-stop always resumes both branches. */
423 && (!target_is_async_p () || sync_execution
)
424 && !(follow_child
|| detach_fork
|| sched_multi
))
426 /* The parent stays blocked inside the vfork syscall until the
427 child execs or exits. If we don't let the child run, then
428 the parent stays blocked. If we're telling the parent to run
429 in the foreground, the user will not be able to ctrl-c to get
430 back the terminal, effectively hanging the debug session. */
431 fprintf_filtered (gdb_stderr
, _("\
432 Can not resume the parent process over vfork in the foreground while\n\
433 holding the child stopped. Try \"set detach-on-fork\" or \
434 \"set schedule-multiple\".\n"));
435 /* FIXME output string > 80 columns. */
441 /* Detach new forked process? */
444 struct cleanup
*old_chain
;
446 /* Before detaching from the child, remove all breakpoints
447 from it. If we forked, then this has already been taken
448 care of by infrun.c. If we vforked however, any
449 breakpoint inserted in the parent is visible in the
450 child, even those added while stopped in a vfork
451 catchpoint. This will remove the breakpoints from the
452 parent also, but they'll be reinserted below. */
455 /* Keep breakpoints list in sync. */
456 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
459 if (info_verbose
|| debug_infrun
)
461 target_terminal_ours_for_output ();
462 fprintf_filtered (gdb_stdlog
,
463 _("Detaching after %s from "
464 "child process %d.\n"),
465 has_vforked
? "vfork" : "fork",
471 struct inferior
*parent_inf
, *child_inf
;
472 struct cleanup
*old_chain
;
474 /* Add process to GDB's tables. */
475 child_inf
= add_inferior (child_pid
);
477 parent_inf
= current_inferior ();
478 child_inf
->attach_flag
= parent_inf
->attach_flag
;
479 copy_terminal_info (child_inf
, parent_inf
);
480 child_inf
->gdbarch
= parent_inf
->gdbarch
;
481 copy_inferior_target_desc_info (child_inf
, parent_inf
);
483 old_chain
= save_inferior_ptid ();
484 save_current_program_space ();
486 inferior_ptid
= ptid_build (child_pid
, child_pid
, 0);
487 add_thread (inferior_ptid
);
488 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
490 /* If this is a vfork child, then the address-space is
491 shared with the parent. */
494 child_inf
->pspace
= parent_inf
->pspace
;
495 child_inf
->aspace
= parent_inf
->aspace
;
497 /* The parent will be frozen until the child is done
498 with the shared region. Keep track of the
500 child_inf
->vfork_parent
= parent_inf
;
501 child_inf
->pending_detach
= 0;
502 parent_inf
->vfork_child
= child_inf
;
503 parent_inf
->pending_detach
= 0;
507 child_inf
->aspace
= new_address_space ();
508 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
509 child_inf
->removable
= 1;
510 set_current_program_space (child_inf
->pspace
);
511 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
513 /* Let the shared library layer (e.g., solib-svr4) learn
514 about this new process, relocate the cloned exec, pull
515 in shared libraries, and install the solib event
516 breakpoint. If a "cloned-VM" event was propagated
517 better throughout the core, this wouldn't be
519 solib_create_inferior_hook (0);
522 do_cleanups (old_chain
);
527 struct inferior
*parent_inf
;
529 parent_inf
= current_inferior ();
531 /* If we detached from the child, then we have to be careful
532 to not insert breakpoints in the parent until the child
533 is done with the shared memory region. However, if we're
534 staying attached to the child, then we can and should
535 insert breakpoints, so that we can debug it. A
536 subsequent child exec or exit is enough to know when does
537 the child stops using the parent's address space. */
538 parent_inf
->waiting_for_vfork_done
= detach_fork
;
539 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
544 /* Follow the child. */
545 struct inferior
*parent_inf
, *child_inf
;
546 struct program_space
*parent_pspace
;
548 if (info_verbose
|| debug_infrun
)
550 target_terminal_ours_for_output ();
551 fprintf_filtered (gdb_stdlog
,
552 _("Attaching after process %d "
553 "%s to child process %d.\n"),
555 has_vforked
? "vfork" : "fork",
559 /* Add the new inferior first, so that the target_detach below
560 doesn't unpush the target. */
562 child_inf
= add_inferior (child_pid
);
564 parent_inf
= current_inferior ();
565 child_inf
->attach_flag
= parent_inf
->attach_flag
;
566 copy_terminal_info (child_inf
, parent_inf
);
567 child_inf
->gdbarch
= parent_inf
->gdbarch
;
568 copy_inferior_target_desc_info (child_inf
, parent_inf
);
570 parent_pspace
= parent_inf
->pspace
;
572 /* If we're vforking, we want to hold on to the parent until the
573 child exits or execs. At child exec or exit time we can
574 remove the old breakpoints from the parent and detach or
575 resume debugging it. Otherwise, detach the parent now; we'll
576 want to reuse it's program/address spaces, but we can't set
577 them to the child before removing breakpoints from the
578 parent, otherwise, the breakpoints module could decide to
579 remove breakpoints from the wrong process (since they'd be
580 assigned to the same address space). */
584 gdb_assert (child_inf
->vfork_parent
== NULL
);
585 gdb_assert (parent_inf
->vfork_child
== NULL
);
586 child_inf
->vfork_parent
= parent_inf
;
587 child_inf
->pending_detach
= 0;
588 parent_inf
->vfork_child
= child_inf
;
589 parent_inf
->pending_detach
= detach_fork
;
590 parent_inf
->waiting_for_vfork_done
= 0;
592 else if (detach_fork
)
594 if (info_verbose
|| debug_infrun
)
596 target_terminal_ours_for_output ();
597 fprintf_filtered (gdb_stdlog
,
598 _("Detaching after fork from "
599 "child process %d.\n"),
603 target_detach (NULL
, 0);
606 /* Note that the detach above makes PARENT_INF dangling. */
608 /* Add the child thread to the appropriate lists, and switch to
609 this new thread, before cloning the program space, and
610 informing the solib layer about this new process. */
612 inferior_ptid
= ptid_build (child_pid
, child_pid
, 0);
613 add_thread (inferior_ptid
);
615 /* If this is a vfork child, then the address-space is shared
616 with the parent. If we detached from the parent, then we can
617 reuse the parent's program/address spaces. */
618 if (has_vforked
|| detach_fork
)
620 child_inf
->pspace
= parent_pspace
;
621 child_inf
->aspace
= child_inf
->pspace
->aspace
;
625 child_inf
->aspace
= new_address_space ();
626 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
627 child_inf
->removable
= 1;
628 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
629 set_current_program_space (child_inf
->pspace
);
630 clone_program_space (child_inf
->pspace
, parent_pspace
);
632 /* Let the shared library layer (e.g., solib-svr4) learn
633 about this new process, relocate the cloned exec, pull in
634 shared libraries, and install the solib event breakpoint.
635 If a "cloned-VM" event was propagated better throughout
636 the core, this wouldn't be required. */
637 solib_create_inferior_hook (0);
641 return target_follow_fork (follow_child
, detach_fork
);
644 /* Tell the target to follow the fork we're stopped at. Returns true
645 if the inferior should be resumed; false, if the target for some
646 reason decided it's best not to resume. */
651 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
652 int should_resume
= 1;
653 struct thread_info
*tp
;
655 /* Copy user stepping state to the new inferior thread. FIXME: the
656 followed fork child thread should have a copy of most of the
657 parent thread structure's run control related fields, not just these.
658 Initialized to avoid "may be used uninitialized" warnings from gcc. */
659 struct breakpoint
*step_resume_breakpoint
= NULL
;
660 struct breakpoint
*exception_resume_breakpoint
= NULL
;
661 CORE_ADDR step_range_start
= 0;
662 CORE_ADDR step_range_end
= 0;
663 struct frame_id step_frame_id
= { 0 };
664 struct interp
*command_interp
= NULL
;
669 struct target_waitstatus wait_status
;
671 /* Get the last target status returned by target_wait(). */
672 get_last_target_status (&wait_ptid
, &wait_status
);
674 /* If not stopped at a fork event, then there's nothing else to
676 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
677 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
680 /* Check if we switched over from WAIT_PTID, since the event was
682 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
683 && !ptid_equal (inferior_ptid
, wait_ptid
))
685 /* We did. Switch back to WAIT_PTID thread, to tell the
686 target to follow it (in either direction). We'll
687 afterwards refuse to resume, and inform the user what
689 switch_to_thread (wait_ptid
);
694 tp
= inferior_thread ();
696 /* If there were any forks/vforks that were caught and are now to be
697 followed, then do so now. */
698 switch (tp
->pending_follow
.kind
)
700 case TARGET_WAITKIND_FORKED
:
701 case TARGET_WAITKIND_VFORKED
:
703 ptid_t parent
, child
;
705 /* If the user did a next/step, etc, over a fork call,
706 preserve the stepping state in the fork child. */
707 if (follow_child
&& should_resume
)
709 step_resume_breakpoint
= clone_momentary_breakpoint
710 (tp
->control
.step_resume_breakpoint
);
711 step_range_start
= tp
->control
.step_range_start
;
712 step_range_end
= tp
->control
.step_range_end
;
713 step_frame_id
= tp
->control
.step_frame_id
;
714 exception_resume_breakpoint
715 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
716 command_interp
= tp
->control
.command_interp
;
718 /* For now, delete the parent's sr breakpoint, otherwise,
719 parent/child sr breakpoints are considered duplicates,
720 and the child version will not be installed. Remove
721 this when the breakpoints module becomes aware of
722 inferiors and address spaces. */
723 delete_step_resume_breakpoint (tp
);
724 tp
->control
.step_range_start
= 0;
725 tp
->control
.step_range_end
= 0;
726 tp
->control
.step_frame_id
= null_frame_id
;
727 delete_exception_resume_breakpoint (tp
);
728 tp
->control
.command_interp
= NULL
;
731 parent
= inferior_ptid
;
732 child
= tp
->pending_follow
.value
.related_pid
;
734 /* Set up inferior(s) as specified by the caller, and tell the
735 target to do whatever is necessary to follow either parent
737 if (follow_fork_inferior (follow_child
, detach_fork
))
739 /* Target refused to follow, or there's some other reason
740 we shouldn't resume. */
745 /* This pending follow fork event is now handled, one way
746 or another. The previous selected thread may be gone
747 from the lists by now, but if it is still around, need
748 to clear the pending follow request. */
749 tp
= find_thread_ptid (parent
);
751 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
753 /* This makes sure we don't try to apply the "Switched
754 over from WAIT_PID" logic above. */
755 nullify_last_target_wait_ptid ();
757 /* If we followed the child, switch to it... */
760 switch_to_thread (child
);
762 /* ... and preserve the stepping state, in case the
763 user was stepping over the fork call. */
766 tp
= inferior_thread ();
767 tp
->control
.step_resume_breakpoint
768 = step_resume_breakpoint
;
769 tp
->control
.step_range_start
= step_range_start
;
770 tp
->control
.step_range_end
= step_range_end
;
771 tp
->control
.step_frame_id
= step_frame_id
;
772 tp
->control
.exception_resume_breakpoint
773 = exception_resume_breakpoint
;
774 tp
->control
.command_interp
= command_interp
;
778 /* If we get here, it was because we're trying to
779 resume from a fork catchpoint, but, the user
780 has switched threads away from the thread that
781 forked. In that case, the resume command
782 issued is most likely not applicable to the
783 child, so just warn, and refuse to resume. */
784 warning (_("Not resuming: switched threads "
785 "before following fork child.\n"));
788 /* Reset breakpoints in the child as appropriate. */
789 follow_inferior_reset_breakpoints ();
792 switch_to_thread (parent
);
796 case TARGET_WAITKIND_SPURIOUS
:
797 /* Nothing to follow. */
800 internal_error (__FILE__
, __LINE__
,
801 "Unexpected pending_follow.kind %d\n",
802 tp
->pending_follow
.kind
);
806 return should_resume
;
810 follow_inferior_reset_breakpoints (void)
812 struct thread_info
*tp
= inferior_thread ();
814 /* Was there a step_resume breakpoint? (There was if the user
815 did a "next" at the fork() call.) If so, explicitly reset its
816 thread number. Cloned step_resume breakpoints are disabled on
817 creation, so enable it here now that it is associated with the
820 step_resumes are a form of bp that are made to be per-thread.
821 Since we created the step_resume bp when the parent process
822 was being debugged, and now are switching to the child process,
823 from the breakpoint package's viewpoint, that's a switch of
824 "threads". We must update the bp's notion of which thread
825 it is for, or it'll be ignored when it triggers. */
827 if (tp
->control
.step_resume_breakpoint
)
829 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
830 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
833 /* Treat exception_resume breakpoints like step_resume breakpoints. */
834 if (tp
->control
.exception_resume_breakpoint
)
836 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
837 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
840 /* Reinsert all breakpoints in the child. The user may have set
841 breakpoints after catching the fork, in which case those
842 were never set in the child, but only in the parent. This makes
843 sure the inserted breakpoints match the breakpoint list. */
845 breakpoint_re_set ();
846 insert_breakpoints ();
849 /* The child has exited or execed: resume threads of the parent the
850 user wanted to be executing. */
853 proceed_after_vfork_done (struct thread_info
*thread
,
856 int pid
= * (int *) arg
;
858 if (ptid_get_pid (thread
->ptid
) == pid
859 && is_running (thread
->ptid
)
860 && !is_executing (thread
->ptid
)
861 && !thread
->stop_requested
862 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
865 fprintf_unfiltered (gdb_stdlog
,
866 "infrun: resuming vfork parent thread %s\n",
867 target_pid_to_str (thread
->ptid
));
869 switch_to_thread (thread
->ptid
);
870 clear_proceed_status (0);
871 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
, 0);
877 /* Called whenever we notice an exec or exit event, to handle
878 detaching or resuming a vfork parent. */
881 handle_vfork_child_exec_or_exit (int exec
)
883 struct inferior
*inf
= current_inferior ();
885 if (inf
->vfork_parent
)
887 int resume_parent
= -1;
889 /* This exec or exit marks the end of the shared memory region
890 between the parent and the child. If the user wanted to
891 detach from the parent, now is the time. */
893 if (inf
->vfork_parent
->pending_detach
)
895 struct thread_info
*tp
;
896 struct cleanup
*old_chain
;
897 struct program_space
*pspace
;
898 struct address_space
*aspace
;
900 /* follow-fork child, detach-on-fork on. */
902 inf
->vfork_parent
->pending_detach
= 0;
906 /* If we're handling a child exit, then inferior_ptid
907 points at the inferior's pid, not to a thread. */
908 old_chain
= save_inferior_ptid ();
909 save_current_program_space ();
910 save_current_inferior ();
913 old_chain
= save_current_space_and_thread ();
915 /* We're letting loose of the parent. */
916 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
917 switch_to_thread (tp
->ptid
);
919 /* We're about to detach from the parent, which implicitly
920 removes breakpoints from its address space. There's a
921 catch here: we want to reuse the spaces for the child,
922 but, parent/child are still sharing the pspace at this
923 point, although the exec in reality makes the kernel give
924 the child a fresh set of new pages. The problem here is
925 that the breakpoints module being unaware of this, would
926 likely chose the child process to write to the parent
927 address space. Swapping the child temporarily away from
928 the spaces has the desired effect. Yes, this is "sort
931 pspace
= inf
->pspace
;
932 aspace
= inf
->aspace
;
936 if (debug_infrun
|| info_verbose
)
938 target_terminal_ours_for_output ();
942 fprintf_filtered (gdb_stdlog
,
943 _("Detaching vfork parent process "
944 "%d after child exec.\n"),
945 inf
->vfork_parent
->pid
);
949 fprintf_filtered (gdb_stdlog
,
950 _("Detaching vfork parent process "
951 "%d after child exit.\n"),
952 inf
->vfork_parent
->pid
);
956 target_detach (NULL
, 0);
959 inf
->pspace
= pspace
;
960 inf
->aspace
= aspace
;
962 do_cleanups (old_chain
);
966 /* We're staying attached to the parent, so, really give the
967 child a new address space. */
968 inf
->pspace
= add_program_space (maybe_new_address_space ());
969 inf
->aspace
= inf
->pspace
->aspace
;
971 set_current_program_space (inf
->pspace
);
973 resume_parent
= inf
->vfork_parent
->pid
;
975 /* Break the bonds. */
976 inf
->vfork_parent
->vfork_child
= NULL
;
980 struct cleanup
*old_chain
;
981 struct program_space
*pspace
;
983 /* If this is a vfork child exiting, then the pspace and
984 aspaces were shared with the parent. Since we're
985 reporting the process exit, we'll be mourning all that is
986 found in the address space, and switching to null_ptid,
987 preparing to start a new inferior. But, since we don't
988 want to clobber the parent's address/program spaces, we
989 go ahead and create a new one for this exiting
992 /* Switch to null_ptid, so that clone_program_space doesn't want
993 to read the selected frame of a dead process. */
994 old_chain
= save_inferior_ptid ();
995 inferior_ptid
= null_ptid
;
997 /* This inferior is dead, so avoid giving the breakpoints
998 module the option to write through to it (cloning a
999 program space resets breakpoints). */
1002 pspace
= add_program_space (maybe_new_address_space ());
1003 set_current_program_space (pspace
);
1005 inf
->symfile_flags
= SYMFILE_NO_READ
;
1006 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1007 inf
->pspace
= pspace
;
1008 inf
->aspace
= pspace
->aspace
;
1010 /* Put back inferior_ptid. We'll continue mourning this
1012 do_cleanups (old_chain
);
1014 resume_parent
= inf
->vfork_parent
->pid
;
1015 /* Break the bonds. */
1016 inf
->vfork_parent
->vfork_child
= NULL
;
1019 inf
->vfork_parent
= NULL
;
1021 gdb_assert (current_program_space
== inf
->pspace
);
1023 if (non_stop
&& resume_parent
!= -1)
1025 /* If the user wanted the parent to be running, let it go
1027 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1030 fprintf_unfiltered (gdb_stdlog
,
1031 "infrun: resuming vfork parent process %d\n",
1034 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1036 do_cleanups (old_chain
);
1041 /* Enum strings for "set|show follow-exec-mode". */
1043 static const char follow_exec_mode_new
[] = "new";
1044 static const char follow_exec_mode_same
[] = "same";
1045 static const char *const follow_exec_mode_names
[] =
1047 follow_exec_mode_new
,
1048 follow_exec_mode_same
,
1052 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1054 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1055 struct cmd_list_element
*c
, const char *value
)
1057 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1060 /* EXECD_PATHNAME is assumed to be non-NULL. */
1063 follow_exec (ptid_t pid
, char *execd_pathname
)
1065 struct thread_info
*th
= inferior_thread ();
1066 struct inferior
*inf
= current_inferior ();
1068 /* This is an exec event that we actually wish to pay attention to.
1069 Refresh our symbol table to the newly exec'd program, remove any
1070 momentary bp's, etc.
1072 If there are breakpoints, they aren't really inserted now,
1073 since the exec() transformed our inferior into a fresh set
1076 We want to preserve symbolic breakpoints on the list, since
1077 we have hopes that they can be reset after the new a.out's
1078 symbol table is read.
1080 However, any "raw" breakpoints must be removed from the list
1081 (e.g., the solib bp's), since their address is probably invalid
1084 And, we DON'T want to call delete_breakpoints() here, since
1085 that may write the bp's "shadow contents" (the instruction
1086 value that was overwritten witha TRAP instruction). Since
1087 we now have a new a.out, those shadow contents aren't valid. */
1089 mark_breakpoints_out ();
1091 update_breakpoints_after_exec ();
1093 /* If there was one, it's gone now. We cannot truly step-to-next
1094 statement through an exec(). */
1095 th
->control
.step_resume_breakpoint
= NULL
;
1096 th
->control
.exception_resume_breakpoint
= NULL
;
1097 th
->control
.single_step_breakpoints
= NULL
;
1098 th
->control
.step_range_start
= 0;
1099 th
->control
.step_range_end
= 0;
1101 /* The target reports the exec event to the main thread, even if
1102 some other thread does the exec, and even if the main thread was
1103 already stopped --- if debugging in non-stop mode, it's possible
1104 the user had the main thread held stopped in the previous image
1105 --- release it now. This is the same behavior as step-over-exec
1106 with scheduler-locking on in all-stop mode. */
1107 th
->stop_requested
= 0;
1109 /* What is this a.out's name? */
1110 printf_unfiltered (_("%s is executing new program: %s\n"),
1111 target_pid_to_str (inferior_ptid
),
1114 /* We've followed the inferior through an exec. Therefore, the
1115 inferior has essentially been killed & reborn. */
1117 gdb_flush (gdb_stdout
);
1119 breakpoint_init_inferior (inf_execd
);
1121 if (gdb_sysroot
&& *gdb_sysroot
)
1123 char *name
= alloca (strlen (gdb_sysroot
)
1124 + strlen (execd_pathname
)
1127 strcpy (name
, gdb_sysroot
);
1128 strcat (name
, execd_pathname
);
1129 execd_pathname
= name
;
1132 /* Reset the shared library package. This ensures that we get a
1133 shlib event when the child reaches "_start", at which point the
1134 dld will have had a chance to initialize the child. */
1135 /* Also, loading a symbol file below may trigger symbol lookups, and
1136 we don't want those to be satisfied by the libraries of the
1137 previous incarnation of this process. */
1138 no_shared_libraries (NULL
, 0);
1140 if (follow_exec_mode_string
== follow_exec_mode_new
)
1142 struct program_space
*pspace
;
1144 /* The user wants to keep the old inferior and program spaces
1145 around. Create a new fresh one, and switch to it. */
1147 inf
= add_inferior (current_inferior ()->pid
);
1148 pspace
= add_program_space (maybe_new_address_space ());
1149 inf
->pspace
= pspace
;
1150 inf
->aspace
= pspace
->aspace
;
1152 exit_inferior_num_silent (current_inferior ()->num
);
1154 set_current_inferior (inf
);
1155 set_current_program_space (pspace
);
1159 /* The old description may no longer be fit for the new image.
1160 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1161 old description; we'll read a new one below. No need to do
1162 this on "follow-exec-mode new", as the old inferior stays
1163 around (its description is later cleared/refetched on
1165 target_clear_description ();
1168 gdb_assert (current_program_space
== inf
->pspace
);
1170 /* That a.out is now the one to use. */
1171 exec_file_attach (execd_pathname
, 0);
1173 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1174 (Position Independent Executable) main symbol file will get applied by
1175 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1176 the breakpoints with the zero displacement. */
1178 symbol_file_add (execd_pathname
,
1180 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
1183 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
1184 set_initial_language ();
1186 /* If the target can specify a description, read it. Must do this
1187 after flipping to the new executable (because the target supplied
1188 description must be compatible with the executable's
1189 architecture, and the old executable may e.g., be 32-bit, while
1190 the new one 64-bit), and before anything involving memory or
1192 target_find_description ();
1194 solib_create_inferior_hook (0);
1196 jit_inferior_created_hook ();
1198 breakpoint_re_set ();
1200 /* Reinsert all breakpoints. (Those which were symbolic have
1201 been reset to the proper address in the new a.out, thanks
1202 to symbol_file_command...). */
1203 insert_breakpoints ();
1205 /* The next resume of this inferior should bring it to the shlib
1206 startup breakpoints. (If the user had also set bp's on
1207 "main" from the old (parent) process, then they'll auto-
1208 matically get reset there in the new process.). */
1211 /* Info about an instruction that is being stepped over. */
1213 struct step_over_info
1215 /* If we're stepping past a breakpoint, this is the address space
1216 and address of the instruction the breakpoint is set at. We'll
1217 skip inserting all breakpoints here. Valid iff ASPACE is
1219 struct address_space
*aspace
;
1222 /* The instruction being stepped over triggers a nonsteppable
1223 watchpoint. If true, we'll skip inserting watchpoints. */
1224 int nonsteppable_watchpoint_p
;
1227 /* The step-over info of the location that is being stepped over.
1229 Note that with async/breakpoint always-inserted mode, a user might
1230 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1231 being stepped over. As setting a new breakpoint inserts all
1232 breakpoints, we need to make sure the breakpoint being stepped over
1233 isn't inserted then. We do that by only clearing the step-over
1234 info when the step-over is actually finished (or aborted).
1236 Presently GDB can only step over one breakpoint at any given time.
1237 Given threads that can't run code in the same address space as the
1238 breakpoint's can't really miss the breakpoint, GDB could be taught
1239 to step-over at most one breakpoint per address space (so this info
1240 could move to the address space object if/when GDB is extended).
1241 The set of breakpoints being stepped over will normally be much
1242 smaller than the set of all breakpoints, so a flag in the
1243 breakpoint location structure would be wasteful. A separate list
1244 also saves complexity and run-time, as otherwise we'd have to go
1245 through all breakpoint locations clearing their flag whenever we
1246 start a new sequence. Similar considerations weigh against storing
1247 this info in the thread object. Plus, not all step overs actually
1248 have breakpoint locations -- e.g., stepping past a single-step
1249 breakpoint, or stepping to complete a non-continuable
1251 static struct step_over_info step_over_info
;
1253 /* Record the address of the breakpoint/instruction we're currently
1257 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1258 int nonsteppable_watchpoint_p
)
1260 step_over_info
.aspace
= aspace
;
1261 step_over_info
.address
= address
;
1262 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1265 /* Called when we're not longer stepping over a breakpoint / an
1266 instruction, so all breakpoints are free to be (re)inserted. */
1269 clear_step_over_info (void)
1271 step_over_info
.aspace
= NULL
;
1272 step_over_info
.address
= 0;
1273 step_over_info
.nonsteppable_watchpoint_p
= 0;
1279 stepping_past_instruction_at (struct address_space
*aspace
,
1282 return (step_over_info
.aspace
!= NULL
1283 && breakpoint_address_match (aspace
, address
,
1284 step_over_info
.aspace
,
1285 step_over_info
.address
));
1291 stepping_past_nonsteppable_watchpoint (void)
1293 return step_over_info
.nonsteppable_watchpoint_p
;
1296 /* Returns true if step-over info is valid. */
1299 step_over_info_valid_p (void)
1301 return (step_over_info
.aspace
!= NULL
1302 || stepping_past_nonsteppable_watchpoint ());
1306 /* Displaced stepping. */
1308 /* In non-stop debugging mode, we must take special care to manage
1309 breakpoints properly; in particular, the traditional strategy for
1310 stepping a thread past a breakpoint it has hit is unsuitable.
1311 'Displaced stepping' is a tactic for stepping one thread past a
1312 breakpoint it has hit while ensuring that other threads running
1313 concurrently will hit the breakpoint as they should.
1315 The traditional way to step a thread T off a breakpoint in a
1316 multi-threaded program in all-stop mode is as follows:
1318 a0) Initially, all threads are stopped, and breakpoints are not
1320 a1) We single-step T, leaving breakpoints uninserted.
1321 a2) We insert breakpoints, and resume all threads.
1323 In non-stop debugging, however, this strategy is unsuitable: we
1324 don't want to have to stop all threads in the system in order to
1325 continue or step T past a breakpoint. Instead, we use displaced
1328 n0) Initially, T is stopped, other threads are running, and
1329 breakpoints are inserted.
1330 n1) We copy the instruction "under" the breakpoint to a separate
1331 location, outside the main code stream, making any adjustments
1332 to the instruction, register, and memory state as directed by
1334 n2) We single-step T over the instruction at its new location.
1335 n3) We adjust the resulting register and memory state as directed
1336 by T's architecture. This includes resetting T's PC to point
1337 back into the main instruction stream.
1340 This approach depends on the following gdbarch methods:
1342 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1343 indicate where to copy the instruction, and how much space must
1344 be reserved there. We use these in step n1.
1346 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1347 address, and makes any necessary adjustments to the instruction,
1348 register contents, and memory. We use this in step n1.
1350 - gdbarch_displaced_step_fixup adjusts registers and memory after
1351 we have successfuly single-stepped the instruction, to yield the
1352 same effect the instruction would have had if we had executed it
1353 at its original address. We use this in step n3.
1355 - gdbarch_displaced_step_free_closure provides cleanup.
1357 The gdbarch_displaced_step_copy_insn and
1358 gdbarch_displaced_step_fixup functions must be written so that
1359 copying an instruction with gdbarch_displaced_step_copy_insn,
1360 single-stepping across the copied instruction, and then applying
1361 gdbarch_displaced_insn_fixup should have the same effects on the
1362 thread's memory and registers as stepping the instruction in place
1363 would have. Exactly which responsibilities fall to the copy and
1364 which fall to the fixup is up to the author of those functions.
1366 See the comments in gdbarch.sh for details.
1368 Note that displaced stepping and software single-step cannot
1369 currently be used in combination, although with some care I think
1370 they could be made to. Software single-step works by placing
1371 breakpoints on all possible subsequent instructions; if the
1372 displaced instruction is a PC-relative jump, those breakpoints
1373 could fall in very strange places --- on pages that aren't
1374 executable, or at addresses that are not proper instruction
1375 boundaries. (We do generally let other threads run while we wait
1376 to hit the software single-step breakpoint, and they might
1377 encounter such a corrupted instruction.) One way to work around
1378 this would be to have gdbarch_displaced_step_copy_insn fully
1379 simulate the effect of PC-relative instructions (and return NULL)
1380 on architectures that use software single-stepping.
1382 In non-stop mode, we can have independent and simultaneous step
1383 requests, so more than one thread may need to simultaneously step
1384 over a breakpoint. The current implementation assumes there is
1385 only one scratch space per process. In this case, we have to
1386 serialize access to the scratch space. If thread A wants to step
1387 over a breakpoint, but we are currently waiting for some other
1388 thread to complete a displaced step, we leave thread A stopped and
1389 place it in the displaced_step_request_queue. Whenever a displaced
1390 step finishes, we pick the next thread in the queue and start a new
1391 displaced step operation on it. See displaced_step_prepare and
1392 displaced_step_fixup for details. */
1394 struct displaced_step_request
1397 struct displaced_step_request
*next
;
1400 /* Per-inferior displaced stepping state. */
1401 struct displaced_step_inferior_state
1403 /* Pointer to next in linked list. */
1404 struct displaced_step_inferior_state
*next
;
1406 /* The process this displaced step state refers to. */
1409 /* A queue of pending displaced stepping requests. One entry per
1410 thread that needs to do a displaced step. */
1411 struct displaced_step_request
*step_request_queue
;
1413 /* If this is not null_ptid, this is the thread carrying out a
1414 displaced single-step in process PID. This thread's state will
1415 require fixing up once it has completed its step. */
1418 /* The architecture the thread had when we stepped it. */
1419 struct gdbarch
*step_gdbarch
;
1421 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1422 for post-step cleanup. */
1423 struct displaced_step_closure
*step_closure
;
1425 /* The address of the original instruction, and the copy we
1427 CORE_ADDR step_original
, step_copy
;
1429 /* Saved contents of copy area. */
1430 gdb_byte
*step_saved_copy
;
1433 /* The list of states of processes involved in displaced stepping
1435 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1437 /* Get the displaced stepping state of process PID. */
1439 static struct displaced_step_inferior_state
*
1440 get_displaced_stepping_state (int pid
)
1442 struct displaced_step_inferior_state
*state
;
1444 for (state
= displaced_step_inferior_states
;
1446 state
= state
->next
)
1447 if (state
->pid
== pid
)
1453 /* Add a new displaced stepping state for process PID to the displaced
1454 stepping state list, or return a pointer to an already existing
1455 entry, if it already exists. Never returns NULL. */
1457 static struct displaced_step_inferior_state
*
1458 add_displaced_stepping_state (int pid
)
1460 struct displaced_step_inferior_state
*state
;
1462 for (state
= displaced_step_inferior_states
;
1464 state
= state
->next
)
1465 if (state
->pid
== pid
)
1468 state
= xcalloc (1, sizeof (*state
));
1470 state
->next
= displaced_step_inferior_states
;
1471 displaced_step_inferior_states
= state
;
1476 /* If inferior is in displaced stepping, and ADDR equals to starting address
1477 of copy area, return corresponding displaced_step_closure. Otherwise,
1480 struct displaced_step_closure
*
1481 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1483 struct displaced_step_inferior_state
*displaced
1484 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1486 /* If checking the mode of displaced instruction in copy area. */
1487 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1488 && (displaced
->step_copy
== addr
))
1489 return displaced
->step_closure
;
1494 /* Remove the displaced stepping state of process PID. */
1497 remove_displaced_stepping_state (int pid
)
1499 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1501 gdb_assert (pid
!= 0);
1503 it
= displaced_step_inferior_states
;
1504 prev_next_p
= &displaced_step_inferior_states
;
1509 *prev_next_p
= it
->next
;
1514 prev_next_p
= &it
->next
;
1520 infrun_inferior_exit (struct inferior
*inf
)
1522 remove_displaced_stepping_state (inf
->pid
);
1525 /* If ON, and the architecture supports it, GDB will use displaced
1526 stepping to step over breakpoints. If OFF, or if the architecture
1527 doesn't support it, GDB will instead use the traditional
1528 hold-and-step approach. If AUTO (which is the default), GDB will
1529 decide which technique to use to step over breakpoints depending on
1530 which of all-stop or non-stop mode is active --- displaced stepping
1531 in non-stop mode; hold-and-step in all-stop mode. */
1533 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1536 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1537 struct cmd_list_element
*c
,
1540 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1541 fprintf_filtered (file
,
1542 _("Debugger's willingness to use displaced stepping "
1543 "to step over breakpoints is %s (currently %s).\n"),
1544 value
, non_stop
? "on" : "off");
1546 fprintf_filtered (file
,
1547 _("Debugger's willingness to use displaced stepping "
1548 "to step over breakpoints is %s.\n"), value
);
1551 /* Return non-zero if displaced stepping can/should be used to step
1552 over breakpoints. */
1555 use_displaced_stepping (struct gdbarch
*gdbarch
)
1557 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
&& non_stop
)
1558 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1559 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1560 && find_record_target () == NULL
);
1563 /* Clean out any stray displaced stepping state. */
1565 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1567 /* Indicate that there is no cleanup pending. */
1568 displaced
->step_ptid
= null_ptid
;
1570 if (displaced
->step_closure
)
1572 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1573 displaced
->step_closure
);
1574 displaced
->step_closure
= NULL
;
1579 displaced_step_clear_cleanup (void *arg
)
1581 struct displaced_step_inferior_state
*state
= arg
;
1583 displaced_step_clear (state
);
1586 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1588 displaced_step_dump_bytes (struct ui_file
*file
,
1589 const gdb_byte
*buf
,
1594 for (i
= 0; i
< len
; i
++)
1595 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1596 fputs_unfiltered ("\n", file
);
1599 /* Prepare to single-step, using displaced stepping.
1601 Note that we cannot use displaced stepping when we have a signal to
1602 deliver. If we have a signal to deliver and an instruction to step
1603 over, then after the step, there will be no indication from the
1604 target whether the thread entered a signal handler or ignored the
1605 signal and stepped over the instruction successfully --- both cases
1606 result in a simple SIGTRAP. In the first case we mustn't do a
1607 fixup, and in the second case we must --- but we can't tell which.
1608 Comments in the code for 'random signals' in handle_inferior_event
1609 explain how we handle this case instead.
1611 Returns 1 if preparing was successful -- this thread is going to be
1612 stepped now; or 0 if displaced stepping this thread got queued. */
1614 displaced_step_prepare (ptid_t ptid
)
1616 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1617 struct thread_info
*tp
= find_thread_ptid (ptid
);
1618 struct regcache
*regcache
= get_thread_regcache (ptid
);
1619 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1620 CORE_ADDR original
, copy
;
1622 struct displaced_step_closure
*closure
;
1623 struct displaced_step_inferior_state
*displaced
;
1626 /* We should never reach this function if the architecture does not
1627 support displaced stepping. */
1628 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1630 /* Disable range stepping while executing in the scratch pad. We
1631 want a single-step even if executing the displaced instruction in
1632 the scratch buffer lands within the stepping range (e.g., a
1634 tp
->control
.may_range_step
= 0;
1636 /* We have to displaced step one thread at a time, as we only have
1637 access to a single scratch space per inferior. */
1639 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1641 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1643 /* Already waiting for a displaced step to finish. Defer this
1644 request and place in queue. */
1645 struct displaced_step_request
*req
, *new_req
;
1647 if (debug_displaced
)
1648 fprintf_unfiltered (gdb_stdlog
,
1649 "displaced: defering step of %s\n",
1650 target_pid_to_str (ptid
));
1652 new_req
= xmalloc (sizeof (*new_req
));
1653 new_req
->ptid
= ptid
;
1654 new_req
->next
= NULL
;
1656 if (displaced
->step_request_queue
)
1658 for (req
= displaced
->step_request_queue
;
1662 req
->next
= new_req
;
1665 displaced
->step_request_queue
= new_req
;
1671 if (debug_displaced
)
1672 fprintf_unfiltered (gdb_stdlog
,
1673 "displaced: stepping %s now\n",
1674 target_pid_to_str (ptid
));
1677 displaced_step_clear (displaced
);
1679 old_cleanups
= save_inferior_ptid ();
1680 inferior_ptid
= ptid
;
1682 original
= regcache_read_pc (regcache
);
1684 copy
= gdbarch_displaced_step_location (gdbarch
);
1685 len
= gdbarch_max_insn_length (gdbarch
);
1687 /* Save the original contents of the copy area. */
1688 displaced
->step_saved_copy
= xmalloc (len
);
1689 ignore_cleanups
= make_cleanup (free_current_contents
,
1690 &displaced
->step_saved_copy
);
1691 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1693 throw_error (MEMORY_ERROR
,
1694 _("Error accessing memory address %s (%s) for "
1695 "displaced-stepping scratch space."),
1696 paddress (gdbarch
, copy
), safe_strerror (status
));
1697 if (debug_displaced
)
1699 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1700 paddress (gdbarch
, copy
));
1701 displaced_step_dump_bytes (gdb_stdlog
,
1702 displaced
->step_saved_copy
,
1706 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1707 original
, copy
, regcache
);
1709 /* We don't support the fully-simulated case at present. */
1710 gdb_assert (closure
);
1712 /* Save the information we need to fix things up if the step
1714 displaced
->step_ptid
= ptid
;
1715 displaced
->step_gdbarch
= gdbarch
;
1716 displaced
->step_closure
= closure
;
1717 displaced
->step_original
= original
;
1718 displaced
->step_copy
= copy
;
1720 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1722 /* Resume execution at the copy. */
1723 regcache_write_pc (regcache
, copy
);
1725 discard_cleanups (ignore_cleanups
);
1727 do_cleanups (old_cleanups
);
1729 if (debug_displaced
)
1730 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1731 paddress (gdbarch
, copy
));
1737 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1738 const gdb_byte
*myaddr
, int len
)
1740 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1742 inferior_ptid
= ptid
;
1743 write_memory (memaddr
, myaddr
, len
);
1744 do_cleanups (ptid_cleanup
);
1747 /* Restore the contents of the copy area for thread PTID. */
1750 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1753 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1755 write_memory_ptid (ptid
, displaced
->step_copy
,
1756 displaced
->step_saved_copy
, len
);
1757 if (debug_displaced
)
1758 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1759 target_pid_to_str (ptid
),
1760 paddress (displaced
->step_gdbarch
,
1761 displaced
->step_copy
));
1765 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1767 struct cleanup
*old_cleanups
;
1768 struct displaced_step_inferior_state
*displaced
1769 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1771 /* Was any thread of this process doing a displaced step? */
1772 if (displaced
== NULL
)
1775 /* Was this event for the pid we displaced? */
1776 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1777 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1780 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1782 displaced_step_restore (displaced
, displaced
->step_ptid
);
1784 /* Did the instruction complete successfully? */
1785 if (signal
== GDB_SIGNAL_TRAP
)
1787 /* Fix up the resulting state. */
1788 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1789 displaced
->step_closure
,
1790 displaced
->step_original
,
1791 displaced
->step_copy
,
1792 get_thread_regcache (displaced
->step_ptid
));
1796 /* Since the instruction didn't complete, all we can do is
1798 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1799 CORE_ADDR pc
= regcache_read_pc (regcache
);
1801 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1802 regcache_write_pc (regcache
, pc
);
1805 do_cleanups (old_cleanups
);
1807 displaced
->step_ptid
= null_ptid
;
1809 /* Are there any pending displaced stepping requests? If so, run
1810 one now. Leave the state object around, since we're likely to
1811 need it again soon. */
1812 while (displaced
->step_request_queue
)
1814 struct displaced_step_request
*head
;
1816 struct regcache
*regcache
;
1817 struct gdbarch
*gdbarch
;
1818 CORE_ADDR actual_pc
;
1819 struct address_space
*aspace
;
1821 head
= displaced
->step_request_queue
;
1823 displaced
->step_request_queue
= head
->next
;
1826 context_switch (ptid
);
1828 regcache
= get_thread_regcache (ptid
);
1829 actual_pc
= regcache_read_pc (regcache
);
1830 aspace
= get_regcache_aspace (regcache
);
1832 if (breakpoint_here_p (aspace
, actual_pc
))
1834 if (debug_displaced
)
1835 fprintf_unfiltered (gdb_stdlog
,
1836 "displaced: stepping queued %s now\n",
1837 target_pid_to_str (ptid
));
1839 displaced_step_prepare (ptid
);
1841 gdbarch
= get_regcache_arch (regcache
);
1843 if (debug_displaced
)
1845 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
1848 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1849 paddress (gdbarch
, actual_pc
));
1850 read_memory (actual_pc
, buf
, sizeof (buf
));
1851 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1854 if (gdbarch_displaced_step_hw_singlestep (gdbarch
,
1855 displaced
->step_closure
))
1856 target_resume (ptid
, 1, GDB_SIGNAL_0
);
1858 target_resume (ptid
, 0, GDB_SIGNAL_0
);
1860 /* Done, we're stepping a thread. */
1866 struct thread_info
*tp
= inferior_thread ();
1868 /* The breakpoint we were sitting under has since been
1870 tp
->control
.trap_expected
= 0;
1872 /* Go back to what we were trying to do. */
1873 step
= currently_stepping (tp
);
1875 if (debug_displaced
)
1876 fprintf_unfiltered (gdb_stdlog
,
1877 "displaced: breakpoint is gone: %s, step(%d)\n",
1878 target_pid_to_str (tp
->ptid
), step
);
1880 target_resume (ptid
, step
, GDB_SIGNAL_0
);
1881 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1883 /* This request was discarded. See if there's any other
1884 thread waiting for its turn. */
1889 /* Update global variables holding ptids to hold NEW_PTID if they were
1890 holding OLD_PTID. */
1892 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1894 struct displaced_step_request
*it
;
1895 struct displaced_step_inferior_state
*displaced
;
1897 if (ptid_equal (inferior_ptid
, old_ptid
))
1898 inferior_ptid
= new_ptid
;
1900 for (displaced
= displaced_step_inferior_states
;
1902 displaced
= displaced
->next
)
1904 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
1905 displaced
->step_ptid
= new_ptid
;
1907 for (it
= displaced
->step_request_queue
; it
; it
= it
->next
)
1908 if (ptid_equal (it
->ptid
, old_ptid
))
1909 it
->ptid
= new_ptid
;
1916 /* Things to clean up if we QUIT out of resume (). */
1918 resume_cleanups (void *ignore
)
1920 if (!ptid_equal (inferior_ptid
, null_ptid
))
1921 delete_single_step_breakpoints (inferior_thread ());
1926 static const char schedlock_off
[] = "off";
1927 static const char schedlock_on
[] = "on";
1928 static const char schedlock_step
[] = "step";
1929 static const char *const scheduler_enums
[] = {
1935 static const char *scheduler_mode
= schedlock_off
;
1937 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1938 struct cmd_list_element
*c
, const char *value
)
1940 fprintf_filtered (file
,
1941 _("Mode for locking scheduler "
1942 "during execution is \"%s\".\n"),
1947 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1949 if (!target_can_lock_scheduler
)
1951 scheduler_mode
= schedlock_off
;
1952 error (_("Target '%s' cannot support this command."), target_shortname
);
1956 /* True if execution commands resume all threads of all processes by
1957 default; otherwise, resume only threads of the current inferior
1959 int sched_multi
= 0;
1961 /* Try to setup for software single stepping over the specified location.
1962 Return 1 if target_resume() should use hardware single step.
1964 GDBARCH the current gdbarch.
1965 PC the location to step over. */
1968 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1972 if (execution_direction
== EXEC_FORWARD
1973 && gdbarch_software_single_step_p (gdbarch
)
1974 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1982 user_visible_resume_ptid (int step
)
1984 /* By default, resume all threads of all processes. */
1985 ptid_t resume_ptid
= RESUME_ALL
;
1987 /* Maybe resume only all threads of the current process. */
1988 if (!sched_multi
&& target_supports_multi_process ())
1990 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
1993 /* Maybe resume a single thread after all. */
1996 /* With non-stop mode on, threads are always handled
1998 resume_ptid
= inferior_ptid
;
2000 else if ((scheduler_mode
== schedlock_on
)
2001 || (scheduler_mode
== schedlock_step
&& step
))
2003 /* User-settable 'scheduler' mode requires solo thread resume. */
2004 resume_ptid
= inferior_ptid
;
2007 /* We may actually resume fewer threads at first, e.g., if a thread
2008 is stopped at a breakpoint that needs stepping-off, but that
2009 should not be visible to the user/frontend, and neither should
2010 the frontend/user be allowed to proceed any of the threads that
2011 happen to be stopped for internal run control handling, if a
2012 previous command wanted them resumed. */
2016 /* Resume the inferior, but allow a QUIT. This is useful if the user
2017 wants to interrupt some lengthy single-stepping operation
2018 (for child processes, the SIGINT goes to the inferior, and so
2019 we get a SIGINT random_signal, but for remote debugging and perhaps
2020 other targets, that's not true).
2022 STEP nonzero if we should step (zero to continue instead).
2023 SIG is the signal to give the inferior (zero for none). */
2025 resume (int step
, enum gdb_signal sig
)
2027 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2028 struct regcache
*regcache
= get_current_regcache ();
2029 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2030 struct thread_info
*tp
= inferior_thread ();
2031 CORE_ADDR pc
= regcache_read_pc (regcache
);
2032 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2034 /* From here on, this represents the caller's step vs continue
2035 request, while STEP represents what we'll actually request the
2036 target to do. STEP can decay from a step to a continue, if e.g.,
2037 we need to implement single-stepping with breakpoints (software
2038 single-step). When deciding whether "set scheduler-locking step"
2039 applies, it's the callers intention that counts. */
2040 const int entry_step
= step
;
2044 if (current_inferior ()->waiting_for_vfork_done
)
2046 /* Don't try to single-step a vfork parent that is waiting for
2047 the child to get out of the shared memory region (by exec'ing
2048 or exiting). This is particularly important on software
2049 single-step archs, as the child process would trip on the
2050 software single step breakpoint inserted for the parent
2051 process. Since the parent will not actually execute any
2052 instruction until the child is out of the shared region (such
2053 are vfork's semantics), it is safe to simply continue it.
2054 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2055 the parent, and tell it to `keep_going', which automatically
2056 re-sets it stepping. */
2058 fprintf_unfiltered (gdb_stdlog
,
2059 "infrun: resume : clear step\n");
2064 fprintf_unfiltered (gdb_stdlog
,
2065 "infrun: resume (step=%d, signal=%s), "
2066 "trap_expected=%d, current thread [%s] at %s\n",
2067 step
, gdb_signal_to_symbol_string (sig
),
2068 tp
->control
.trap_expected
,
2069 target_pid_to_str (inferior_ptid
),
2070 paddress (gdbarch
, pc
));
2072 /* Normally, by the time we reach `resume', the breakpoints are either
2073 removed or inserted, as appropriate. The exception is if we're sitting
2074 at a permanent breakpoint; we need to step over it, but permanent
2075 breakpoints can't be removed. So we have to test for it here. */
2076 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2078 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
2079 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2082 The program is stopped at a permanent breakpoint, but GDB does not know\n\
2083 how to step past a permanent breakpoint on this architecture. Try using\n\
2084 a command like `return' or `jump' to continue execution."));
2087 /* If we have a breakpoint to step over, make sure to do a single
2088 step only. Same if we have software watchpoints. */
2089 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2090 tp
->control
.may_range_step
= 0;
2092 /* If enabled, step over breakpoints by executing a copy of the
2093 instruction at a different address.
2095 We can't use displaced stepping when we have a signal to deliver;
2096 the comments for displaced_step_prepare explain why. The
2097 comments in the handle_inferior event for dealing with 'random
2098 signals' explain what we do instead.
2100 We can't use displaced stepping when we are waiting for vfork_done
2101 event, displaced stepping breaks the vfork child similarly as single
2102 step software breakpoint. */
2103 if (use_displaced_stepping (gdbarch
)
2104 && tp
->control
.trap_expected
2105 && sig
== GDB_SIGNAL_0
2106 && !current_inferior ()->waiting_for_vfork_done
)
2108 struct displaced_step_inferior_state
*displaced
;
2110 if (!displaced_step_prepare (inferior_ptid
))
2112 /* Got placed in displaced stepping queue. Will be resumed
2113 later when all the currently queued displaced stepping
2114 requests finish. The thread is not executing at this
2115 point, and the call to set_executing will be made later.
2116 But we need to call set_running here, since from the
2117 user/frontend's point of view, threads were set running.
2118 Unless we're calling an inferior function, as in that
2119 case we pretend the inferior doesn't run at all. */
2120 if (!tp
->control
.in_infcall
)
2121 set_running (user_visible_resume_ptid (entry_step
), 1);
2122 discard_cleanups (old_cleanups
);
2126 /* Update pc to reflect the new address from which we will execute
2127 instructions due to displaced stepping. */
2128 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2130 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2131 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2132 displaced
->step_closure
);
2135 /* Do we need to do it the hard way, w/temp breakpoints? */
2137 step
= maybe_software_singlestep (gdbarch
, pc
);
2139 /* Currently, our software single-step implementation leads to different
2140 results than hardware single-stepping in one situation: when stepping
2141 into delivering a signal which has an associated signal handler,
2142 hardware single-step will stop at the first instruction of the handler,
2143 while software single-step will simply skip execution of the handler.
2145 For now, this difference in behavior is accepted since there is no
2146 easy way to actually implement single-stepping into a signal handler
2147 without kernel support.
2149 However, there is one scenario where this difference leads to follow-on
2150 problems: if we're stepping off a breakpoint by removing all breakpoints
2151 and then single-stepping. In this case, the software single-step
2152 behavior means that even if there is a *breakpoint* in the signal
2153 handler, GDB still would not stop.
2155 Fortunately, we can at least fix this particular issue. We detect
2156 here the case where we are about to deliver a signal while software
2157 single-stepping with breakpoints removed. In this situation, we
2158 revert the decisions to remove all breakpoints and insert single-
2159 step breakpoints, and instead we install a step-resume breakpoint
2160 at the current address, deliver the signal without stepping, and
2161 once we arrive back at the step-resume breakpoint, actually step
2162 over the breakpoint we originally wanted to step over. */
2163 if (thread_has_single_step_breakpoints_set (tp
)
2164 && sig
!= GDB_SIGNAL_0
2165 && step_over_info_valid_p ())
2167 /* If we have nested signals or a pending signal is delivered
2168 immediately after a handler returns, might might already have
2169 a step-resume breakpoint set on the earlier handler. We cannot
2170 set another step-resume breakpoint; just continue on until the
2171 original breakpoint is hit. */
2172 if (tp
->control
.step_resume_breakpoint
== NULL
)
2174 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2175 tp
->step_after_step_resume_breakpoint
= 1;
2178 delete_single_step_breakpoints (tp
);
2180 clear_step_over_info ();
2181 tp
->control
.trap_expected
= 0;
2183 insert_breakpoints ();
2186 /* If STEP is set, it's a request to use hardware stepping
2187 facilities. But in that case, we should never
2188 use singlestep breakpoint. */
2189 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2191 /* Decide the set of threads to ask the target to resume. Start
2192 by assuming everything will be resumed, than narrow the set
2193 by applying increasingly restricting conditions. */
2194 resume_ptid
= user_visible_resume_ptid (entry_step
);
2196 /* Even if RESUME_PTID is a wildcard, and we end up resuming less
2197 (e.g., we might need to step over a breakpoint), from the
2198 user/frontend's point of view, all threads in RESUME_PTID are now
2199 running. Unless we're calling an inferior function, as in that
2200 case pretend we inferior doesn't run at all. */
2201 if (!tp
->control
.in_infcall
)
2202 set_running (resume_ptid
, 1);
2204 /* Maybe resume a single thread after all. */
2205 if ((step
|| thread_has_single_step_breakpoints_set (tp
))
2206 && tp
->control
.trap_expected
)
2208 /* We're allowing a thread to run past a breakpoint it has
2209 hit, by single-stepping the thread with the breakpoint
2210 removed. In which case, we need to single-step only this
2211 thread, and keep others stopped, as they can miss this
2212 breakpoint if allowed to run. */
2213 resume_ptid
= inferior_ptid
;
2216 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2218 /* Most targets can step a breakpoint instruction, thus
2219 executing it normally. But if this one cannot, just
2220 continue and we will hit it anyway. */
2221 if (step
&& breakpoint_inserted_here_p (aspace
, pc
))
2226 && use_displaced_stepping (gdbarch
)
2227 && tp
->control
.trap_expected
)
2229 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
2230 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2231 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2234 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2235 paddress (resume_gdbarch
, actual_pc
));
2236 read_memory (actual_pc
, buf
, sizeof (buf
));
2237 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2240 if (tp
->control
.may_range_step
)
2242 /* If we're resuming a thread with the PC out of the step
2243 range, then we're doing some nested/finer run control
2244 operation, like stepping the thread out of the dynamic
2245 linker or the displaced stepping scratch pad. We
2246 shouldn't have allowed a range step then. */
2247 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2250 /* Install inferior's terminal modes. */
2251 target_terminal_inferior ();
2253 /* Avoid confusing the next resume, if the next stop/resume
2254 happens to apply to another thread. */
2255 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2257 /* Advise target which signals may be handled silently. If we have
2258 removed breakpoints because we are stepping over one (in any
2259 thread), we need to receive all signals to avoid accidentally
2260 skipping a breakpoint during execution of a signal handler. */
2261 if (step_over_info_valid_p ())
2262 target_pass_signals (0, NULL
);
2264 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2266 target_resume (resume_ptid
, step
, sig
);
2268 discard_cleanups (old_cleanups
);
2273 /* Clear out all variables saying what to do when inferior is continued.
2274 First do this, then set the ones you want, then call `proceed'. */
2277 clear_proceed_status_thread (struct thread_info
*tp
)
2280 fprintf_unfiltered (gdb_stdlog
,
2281 "infrun: clear_proceed_status_thread (%s)\n",
2282 target_pid_to_str (tp
->ptid
));
2284 /* If this signal should not be seen by program, give it zero.
2285 Used for debugging signals. */
2286 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2287 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2289 tp
->control
.trap_expected
= 0;
2290 tp
->control
.step_range_start
= 0;
2291 tp
->control
.step_range_end
= 0;
2292 tp
->control
.may_range_step
= 0;
2293 tp
->control
.step_frame_id
= null_frame_id
;
2294 tp
->control
.step_stack_frame_id
= null_frame_id
;
2295 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2296 tp
->stop_requested
= 0;
2298 tp
->control
.stop_step
= 0;
2300 tp
->control
.proceed_to_finish
= 0;
2302 tp
->control
.command_interp
= NULL
;
2304 /* Discard any remaining commands or status from previous stop. */
2305 bpstat_clear (&tp
->control
.stop_bpstat
);
2309 clear_proceed_status (int step
)
2313 struct thread_info
*tp
;
2316 resume_ptid
= user_visible_resume_ptid (step
);
2318 /* In all-stop mode, delete the per-thread status of all threads
2319 we're about to resume, implicitly and explicitly. */
2320 ALL_NON_EXITED_THREADS (tp
)
2322 if (!ptid_match (tp
->ptid
, resume_ptid
))
2324 clear_proceed_status_thread (tp
);
2328 if (!ptid_equal (inferior_ptid
, null_ptid
))
2330 struct inferior
*inferior
;
2334 /* If in non-stop mode, only delete the per-thread status of
2335 the current thread. */
2336 clear_proceed_status_thread (inferior_thread ());
2339 inferior
= current_inferior ();
2340 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2343 stop_after_trap
= 0;
2345 clear_step_over_info ();
2347 observer_notify_about_to_proceed ();
2351 regcache_xfree (stop_registers
);
2352 stop_registers
= NULL
;
2356 /* Returns true if TP is still stopped at a breakpoint that needs
2357 stepping-over in order to make progress. If the breakpoint is gone
2358 meanwhile, we can skip the whole step-over dance. */
2361 thread_still_needs_step_over (struct thread_info
*tp
)
2363 if (tp
->stepping_over_breakpoint
)
2365 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2367 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2368 regcache_read_pc (regcache
)))
2371 tp
->stepping_over_breakpoint
= 0;
2377 /* Returns true if scheduler locking applies. STEP indicates whether
2378 we're about to do a step/next-like command to a thread. */
2381 schedlock_applies (int step
)
2383 return (scheduler_mode
== schedlock_on
2384 || (scheduler_mode
== schedlock_step
2388 /* Look a thread other than EXCEPT that has previously reported a
2389 breakpoint event, and thus needs a step-over in order to make
2390 progress. Returns NULL is none is found. STEP indicates whether
2391 we're about to step the current thread, in order to decide whether
2392 "set scheduler-locking step" applies. */
2394 static struct thread_info
*
2395 find_thread_needs_step_over (int step
, struct thread_info
*except
)
2397 struct thread_info
*tp
, *current
;
2399 /* With non-stop mode on, threads are always handled individually. */
2400 gdb_assert (! non_stop
);
2402 current
= inferior_thread ();
2404 /* If scheduler locking applies, we can avoid iterating over all
2406 if (schedlock_applies (step
))
2408 if (except
!= current
2409 && thread_still_needs_step_over (current
))
2415 ALL_NON_EXITED_THREADS (tp
)
2417 /* Ignore the EXCEPT thread. */
2420 /* Ignore threads of processes we're not resuming. */
2422 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (inferior_ptid
))
2425 if (thread_still_needs_step_over (tp
))
2432 /* Basic routine for continuing the program in various fashions.
2434 ADDR is the address to resume at, or -1 for resume where stopped.
2435 SIGGNAL is the signal to give it, or 0 for none,
2436 or -1 for act according to how it stopped.
2437 STEP is nonzero if should trap after one instruction.
2438 -1 means return after that and print nothing.
2439 You should probably set various step_... variables
2440 before calling here, if you are stepping.
2442 You should call clear_proceed_status before calling proceed. */
2445 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
, int step
)
2447 struct regcache
*regcache
;
2448 struct gdbarch
*gdbarch
;
2449 struct thread_info
*tp
;
2451 struct address_space
*aspace
;
2453 /* If we're stopped at a fork/vfork, follow the branch set by the
2454 "set follow-fork-mode" command; otherwise, we'll just proceed
2455 resuming the current thread. */
2456 if (!follow_fork ())
2458 /* The target for some reason decided not to resume. */
2460 if (target_can_async_p ())
2461 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2465 /* We'll update this if & when we switch to a new thread. */
2466 previous_inferior_ptid
= inferior_ptid
;
2468 regcache
= get_current_regcache ();
2469 gdbarch
= get_regcache_arch (regcache
);
2470 aspace
= get_regcache_aspace (regcache
);
2471 pc
= regcache_read_pc (regcache
);
2472 tp
= inferior_thread ();
2475 step_start_function
= find_pc_function (pc
);
2477 stop_after_trap
= 1;
2479 /* Fill in with reasonable starting values. */
2480 init_thread_stepping_state (tp
);
2482 if (addr
== (CORE_ADDR
) -1)
2484 if (pc
== stop_pc
&& breakpoint_here_p (aspace
, pc
)
2485 && execution_direction
!= EXEC_REVERSE
)
2486 /* There is a breakpoint at the address we will resume at,
2487 step one instruction before inserting breakpoints so that
2488 we do not stop right away (and report a second hit at this
2491 Note, we don't do this in reverse, because we won't
2492 actually be executing the breakpoint insn anyway.
2493 We'll be (un-)executing the previous instruction. */
2494 tp
->stepping_over_breakpoint
= 1;
2495 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2496 && gdbarch_single_step_through_delay (gdbarch
,
2497 get_current_frame ()))
2498 /* We stepped onto an instruction that needs to be stepped
2499 again before re-inserting the breakpoint, do so. */
2500 tp
->stepping_over_breakpoint
= 1;
2504 regcache_write_pc (regcache
, addr
);
2507 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2508 tp
->suspend
.stop_signal
= siggnal
;
2510 /* Record the interpreter that issued the execution command that
2511 caused this thread to resume. If the top level interpreter is
2512 MI/async, and the execution command was a CLI command
2513 (next/step/etc.), we'll want to print stop event output to the MI
2514 console channel (the stepped-to line, etc.), as if the user
2515 entered the execution command on a real GDB console. */
2516 inferior_thread ()->control
.command_interp
= command_interp ();
2519 fprintf_unfiltered (gdb_stdlog
,
2520 "infrun: proceed (addr=%s, signal=%s, step=%d)\n",
2521 paddress (gdbarch
, addr
),
2522 gdb_signal_to_symbol_string (siggnal
), step
);
2525 /* In non-stop, each thread is handled individually. The context
2526 must already be set to the right thread here. */
2530 struct thread_info
*step_over
;
2532 /* In a multi-threaded task we may select another thread and
2533 then continue or step.
2535 But if the old thread was stopped at a breakpoint, it will
2536 immediately cause another breakpoint stop without any
2537 execution (i.e. it will report a breakpoint hit incorrectly).
2538 So we must step over it first.
2540 Look for a thread other than the current (TP) that reported a
2541 breakpoint hit and hasn't been resumed yet since. */
2542 step_over
= find_thread_needs_step_over (step
, tp
);
2543 if (step_over
!= NULL
)
2546 fprintf_unfiltered (gdb_stdlog
,
2547 "infrun: need to step-over [%s] first\n",
2548 target_pid_to_str (step_over
->ptid
));
2550 /* Store the prev_pc for the stepping thread too, needed by
2551 switch_back_to_stepping thread. */
2552 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2553 switch_to_thread (step_over
->ptid
);
2558 /* If we need to step over a breakpoint, and we're not using
2559 displaced stepping to do so, insert all breakpoints (watchpoints,
2560 etc.) but the one we're stepping over, step one instruction, and
2561 then re-insert the breakpoint when that step is finished. */
2562 if (tp
->stepping_over_breakpoint
&& !use_displaced_stepping (gdbarch
))
2564 struct regcache
*regcache
= get_current_regcache ();
2566 set_step_over_info (get_regcache_aspace (regcache
),
2567 regcache_read_pc (regcache
), 0);
2570 clear_step_over_info ();
2572 insert_breakpoints ();
2574 tp
->control
.trap_expected
= tp
->stepping_over_breakpoint
;
2576 annotate_starting ();
2578 /* Make sure that output from GDB appears before output from the
2580 gdb_flush (gdb_stdout
);
2582 /* Refresh prev_pc value just prior to resuming. This used to be
2583 done in stop_waiting, however, setting prev_pc there did not handle
2584 scenarios such as inferior function calls or returning from
2585 a function via the return command. In those cases, the prev_pc
2586 value was not set properly for subsequent commands. The prev_pc value
2587 is used to initialize the starting line number in the ecs. With an
2588 invalid value, the gdb next command ends up stopping at the position
2589 represented by the next line table entry past our start position.
2590 On platforms that generate one line table entry per line, this
2591 is not a problem. However, on the ia64, the compiler generates
2592 extraneous line table entries that do not increase the line number.
2593 When we issue the gdb next command on the ia64 after an inferior call
2594 or a return command, we often end up a few instructions forward, still
2595 within the original line we started.
2597 An attempt was made to refresh the prev_pc at the same time the
2598 execution_control_state is initialized (for instance, just before
2599 waiting for an inferior event). But this approach did not work
2600 because of platforms that use ptrace, where the pc register cannot
2601 be read unless the inferior is stopped. At that point, we are not
2602 guaranteed the inferior is stopped and so the regcache_read_pc() call
2603 can fail. Setting the prev_pc value here ensures the value is updated
2604 correctly when the inferior is stopped. */
2605 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2607 /* Resume inferior. */
2608 resume (tp
->control
.trap_expected
|| step
|| bpstat_should_step (),
2609 tp
->suspend
.stop_signal
);
2611 /* Wait for it to stop (if not standalone)
2612 and in any case decode why it stopped, and act accordingly. */
2613 /* Do this only if we are not using the event loop, or if the target
2614 does not support asynchronous execution. */
2615 if (!target_can_async_p ())
2617 wait_for_inferior ();
2623 /* Start remote-debugging of a machine over a serial link. */
2626 start_remote (int from_tty
)
2628 struct inferior
*inferior
;
2630 inferior
= current_inferior ();
2631 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
2633 /* Always go on waiting for the target, regardless of the mode. */
2634 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2635 indicate to wait_for_inferior that a target should timeout if
2636 nothing is returned (instead of just blocking). Because of this,
2637 targets expecting an immediate response need to, internally, set
2638 things up so that the target_wait() is forced to eventually
2640 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2641 differentiate to its caller what the state of the target is after
2642 the initial open has been performed. Here we're assuming that
2643 the target has stopped. It should be possible to eventually have
2644 target_open() return to the caller an indication that the target
2645 is currently running and GDB state should be set to the same as
2646 for an async run. */
2647 wait_for_inferior ();
2649 /* Now that the inferior has stopped, do any bookkeeping like
2650 loading shared libraries. We want to do this before normal_stop,
2651 so that the displayed frame is up to date. */
2652 post_create_inferior (¤t_target
, from_tty
);
2657 /* Initialize static vars when a new inferior begins. */
2660 init_wait_for_inferior (void)
2662 /* These are meaningless until the first time through wait_for_inferior. */
2664 breakpoint_init_inferior (inf_starting
);
2666 clear_proceed_status (0);
2668 target_last_wait_ptid
= minus_one_ptid
;
2670 previous_inferior_ptid
= inferior_ptid
;
2672 /* Discard any skipped inlined frames. */
2673 clear_inline_frame_state (minus_one_ptid
);
2677 /* This enum encodes possible reasons for doing a target_wait, so that
2678 wfi can call target_wait in one place. (Ultimately the call will be
2679 moved out of the infinite loop entirely.) */
2683 infwait_normal_state
,
2684 infwait_step_watch_state
,
2685 infwait_nonstep_watch_state
2688 /* Current inferior wait state. */
2689 static enum infwait_states infwait_state
;
2691 /* Data to be passed around while handling an event. This data is
2692 discarded between events. */
2693 struct execution_control_state
2696 /* The thread that got the event, if this was a thread event; NULL
2698 struct thread_info
*event_thread
;
2700 struct target_waitstatus ws
;
2701 int stop_func_filled_in
;
2702 CORE_ADDR stop_func_start
;
2703 CORE_ADDR stop_func_end
;
2704 const char *stop_func_name
;
2707 /* True if the event thread hit the single-step breakpoint of
2708 another thread. Thus the event doesn't cause a stop, the thread
2709 needs to be single-stepped past the single-step breakpoint before
2710 we can switch back to the original stepping thread. */
2711 int hit_singlestep_breakpoint
;
2714 static void handle_inferior_event (struct execution_control_state
*ecs
);
2716 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2717 struct execution_control_state
*ecs
);
2718 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2719 struct execution_control_state
*ecs
);
2720 static void handle_signal_stop (struct execution_control_state
*ecs
);
2721 static void check_exception_resume (struct execution_control_state
*,
2722 struct frame_info
*);
2724 static void end_stepping_range (struct execution_control_state
*ecs
);
2725 static void stop_waiting (struct execution_control_state
*ecs
);
2726 static void prepare_to_wait (struct execution_control_state
*ecs
);
2727 static void keep_going (struct execution_control_state
*ecs
);
2728 static void process_event_stop_test (struct execution_control_state
*ecs
);
2729 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
2731 /* Callback for iterate over threads. If the thread is stopped, but
2732 the user/frontend doesn't know about that yet, go through
2733 normal_stop, as if the thread had just stopped now. ARG points at
2734 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2735 ptid_is_pid(PTID) is true, applies to all threads of the process
2736 pointed at by PTID. Otherwise, apply only to the thread pointed by
2740 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2742 ptid_t ptid
= * (ptid_t
*) arg
;
2744 if ((ptid_equal (info
->ptid
, ptid
)
2745 || ptid_equal (minus_one_ptid
, ptid
)
2746 || (ptid_is_pid (ptid
)
2747 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2748 && is_running (info
->ptid
)
2749 && !is_executing (info
->ptid
))
2751 struct cleanup
*old_chain
;
2752 struct execution_control_state ecss
;
2753 struct execution_control_state
*ecs
= &ecss
;
2755 memset (ecs
, 0, sizeof (*ecs
));
2757 old_chain
= make_cleanup_restore_current_thread ();
2759 overlay_cache_invalid
= 1;
2760 /* Flush target cache before starting to handle each event.
2761 Target was running and cache could be stale. This is just a
2762 heuristic. Running threads may modify target memory, but we
2763 don't get any event. */
2764 target_dcache_invalidate ();
2766 /* Go through handle_inferior_event/normal_stop, so we always
2767 have consistent output as if the stop event had been
2769 ecs
->ptid
= info
->ptid
;
2770 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2771 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2772 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
2774 handle_inferior_event (ecs
);
2776 if (!ecs
->wait_some_more
)
2778 struct thread_info
*tp
;
2782 /* Finish off the continuations. */
2783 tp
= inferior_thread ();
2784 do_all_intermediate_continuations_thread (tp
, 1);
2785 do_all_continuations_thread (tp
, 1);
2788 do_cleanups (old_chain
);
2794 /* This function is attached as a "thread_stop_requested" observer.
2795 Cleanup local state that assumed the PTID was to be resumed, and
2796 report the stop to the frontend. */
2799 infrun_thread_stop_requested (ptid_t ptid
)
2801 struct displaced_step_inferior_state
*displaced
;
2803 /* PTID was requested to stop. Remove it from the displaced
2804 stepping queue, so we don't try to resume it automatically. */
2806 for (displaced
= displaced_step_inferior_states
;
2808 displaced
= displaced
->next
)
2810 struct displaced_step_request
*it
, **prev_next_p
;
2812 it
= displaced
->step_request_queue
;
2813 prev_next_p
= &displaced
->step_request_queue
;
2816 if (ptid_match (it
->ptid
, ptid
))
2818 *prev_next_p
= it
->next
;
2824 prev_next_p
= &it
->next
;
2831 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2835 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2837 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2838 nullify_last_target_wait_ptid ();
2841 /* Delete the step resume, single-step and longjmp/exception resume
2842 breakpoints of TP. */
2845 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
2847 delete_step_resume_breakpoint (tp
);
2848 delete_exception_resume_breakpoint (tp
);
2849 delete_single_step_breakpoints (tp
);
2852 /* If the target still has execution, call FUNC for each thread that
2853 just stopped. In all-stop, that's all the non-exited threads; in
2854 non-stop, that's the current thread, only. */
2856 typedef void (*for_each_just_stopped_thread_callback_func
)
2857 (struct thread_info
*tp
);
2860 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
2862 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
2867 /* If in non-stop mode, only the current thread stopped. */
2868 func (inferior_thread ());
2872 struct thread_info
*tp
;
2874 /* In all-stop mode, all threads have stopped. */
2875 ALL_NON_EXITED_THREADS (tp
)
2882 /* Delete the step resume and longjmp/exception resume breakpoints of
2883 the threads that just stopped. */
2886 delete_just_stopped_threads_infrun_breakpoints (void)
2888 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
2891 /* Delete the single-step breakpoints of the threads that just
2895 delete_just_stopped_threads_single_step_breakpoints (void)
2897 for_each_just_stopped_thread (delete_single_step_breakpoints
);
2900 /* A cleanup wrapper. */
2903 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
2905 delete_just_stopped_threads_infrun_breakpoints ();
2908 /* Pretty print the results of target_wait, for debugging purposes. */
2911 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
2912 const struct target_waitstatus
*ws
)
2914 char *status_string
= target_waitstatus_to_string (ws
);
2915 struct ui_file
*tmp_stream
= mem_fileopen ();
2918 /* The text is split over several lines because it was getting too long.
2919 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2920 output as a unit; we want only one timestamp printed if debug_timestamp
2923 fprintf_unfiltered (tmp_stream
,
2924 "infrun: target_wait (%d", ptid_get_pid (waiton_ptid
));
2925 if (ptid_get_pid (waiton_ptid
) != -1)
2926 fprintf_unfiltered (tmp_stream
,
2927 " [%s]", target_pid_to_str (waiton_ptid
));
2928 fprintf_unfiltered (tmp_stream
, ", status) =\n");
2929 fprintf_unfiltered (tmp_stream
,
2930 "infrun: %d [%s],\n",
2931 ptid_get_pid (result_ptid
),
2932 target_pid_to_str (result_ptid
));
2933 fprintf_unfiltered (tmp_stream
,
2937 text
= ui_file_xstrdup (tmp_stream
, NULL
);
2939 /* This uses %s in part to handle %'s in the text, but also to avoid
2940 a gcc error: the format attribute requires a string literal. */
2941 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
2943 xfree (status_string
);
2945 ui_file_delete (tmp_stream
);
2948 /* Prepare and stabilize the inferior for detaching it. E.g.,
2949 detaching while a thread is displaced stepping is a recipe for
2950 crashing it, as nothing would readjust the PC out of the scratch
2954 prepare_for_detach (void)
2956 struct inferior
*inf
= current_inferior ();
2957 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
2958 struct cleanup
*old_chain_1
;
2959 struct displaced_step_inferior_state
*displaced
;
2961 displaced
= get_displaced_stepping_state (inf
->pid
);
2963 /* Is any thread of this process displaced stepping? If not,
2964 there's nothing else to do. */
2965 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
2969 fprintf_unfiltered (gdb_stdlog
,
2970 "displaced-stepping in-process while detaching");
2972 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
2975 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
2977 struct cleanup
*old_chain_2
;
2978 struct execution_control_state ecss
;
2979 struct execution_control_state
*ecs
;
2982 memset (ecs
, 0, sizeof (*ecs
));
2984 overlay_cache_invalid
= 1;
2985 /* Flush target cache before starting to handle each event.
2986 Target was running and cache could be stale. This is just a
2987 heuristic. Running threads may modify target memory, but we
2988 don't get any event. */
2989 target_dcache_invalidate ();
2991 if (deprecated_target_wait_hook
)
2992 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
2994 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
2997 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
2999 /* If an error happens while handling the event, propagate GDB's
3000 knowledge of the executing state to the frontend/user running
3002 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3005 /* Now figure out what to do with the result of the result. */
3006 handle_inferior_event (ecs
);
3008 /* No error, don't finish the state yet. */
3009 discard_cleanups (old_chain_2
);
3011 /* Breakpoints and watchpoints are not installed on the target
3012 at this point, and signals are passed directly to the
3013 inferior, so this must mean the process is gone. */
3014 if (!ecs
->wait_some_more
)
3016 discard_cleanups (old_chain_1
);
3017 error (_("Program exited while detaching"));
3021 discard_cleanups (old_chain_1
);
3024 /* Wait for control to return from inferior to debugger.
3026 If inferior gets a signal, we may decide to start it up again
3027 instead of returning. That is why there is a loop in this function.
3028 When this function actually returns it means the inferior
3029 should be left stopped and GDB should read more commands. */
3032 wait_for_inferior (void)
3034 struct cleanup
*old_cleanups
;
3038 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3041 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3046 struct execution_control_state ecss
;
3047 struct execution_control_state
*ecs
= &ecss
;
3048 struct cleanup
*old_chain
;
3049 ptid_t waiton_ptid
= minus_one_ptid
;
3051 memset (ecs
, 0, sizeof (*ecs
));
3053 overlay_cache_invalid
= 1;
3055 /* Flush target cache before starting to handle each event.
3056 Target was running and cache could be stale. This is just a
3057 heuristic. Running threads may modify target memory, but we
3058 don't get any event. */
3059 target_dcache_invalidate ();
3061 if (deprecated_target_wait_hook
)
3062 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
3064 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
3067 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3069 /* If an error happens while handling the event, propagate GDB's
3070 knowledge of the executing state to the frontend/user running
3072 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3074 /* Now figure out what to do with the result of the result. */
3075 handle_inferior_event (ecs
);
3077 /* No error, don't finish the state yet. */
3078 discard_cleanups (old_chain
);
3080 if (!ecs
->wait_some_more
)
3084 do_cleanups (old_cleanups
);
3087 /* Asynchronous version of wait_for_inferior. It is called by the
3088 event loop whenever a change of state is detected on the file
3089 descriptor corresponding to the target. It can be called more than
3090 once to complete a single execution command. In such cases we need
3091 to keep the state in a global variable ECSS. If it is the last time
3092 that this function is called for a single execution command, then
3093 report to the user that the inferior has stopped, and do the
3094 necessary cleanups. */
3097 fetch_inferior_event (void *client_data
)
3099 struct execution_control_state ecss
;
3100 struct execution_control_state
*ecs
= &ecss
;
3101 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3102 struct cleanup
*ts_old_chain
;
3103 int was_sync
= sync_execution
;
3105 ptid_t waiton_ptid
= minus_one_ptid
;
3107 memset (ecs
, 0, sizeof (*ecs
));
3109 /* We're handling a live event, so make sure we're doing live
3110 debugging. If we're looking at traceframes while the target is
3111 running, we're going to need to get back to that mode after
3112 handling the event. */
3115 make_cleanup_restore_current_traceframe ();
3116 set_current_traceframe (-1);
3120 /* In non-stop mode, the user/frontend should not notice a thread
3121 switch due to internal events. Make sure we reverse to the
3122 user selected thread and frame after handling the event and
3123 running any breakpoint commands. */
3124 make_cleanup_restore_current_thread ();
3126 overlay_cache_invalid
= 1;
3127 /* Flush target cache before starting to handle each event. Target
3128 was running and cache could be stale. This is just a heuristic.
3129 Running threads may modify target memory, but we don't get any
3131 target_dcache_invalidate ();
3133 make_cleanup_restore_integer (&execution_direction
);
3134 execution_direction
= target_execution_direction ();
3136 if (deprecated_target_wait_hook
)
3138 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3140 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3143 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3145 /* If an error happens while handling the event, propagate GDB's
3146 knowledge of the executing state to the frontend/user running
3149 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3151 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3153 /* Get executed before make_cleanup_restore_current_thread above to apply
3154 still for the thread which has thrown the exception. */
3155 make_bpstat_clear_actions_cleanup ();
3157 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3159 /* Now figure out what to do with the result of the result. */
3160 handle_inferior_event (ecs
);
3162 if (!ecs
->wait_some_more
)
3164 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3166 delete_just_stopped_threads_infrun_breakpoints ();
3168 /* We may not find an inferior if this was a process exit. */
3169 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3172 if (target_has_execution
3173 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
3174 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3175 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3176 && ecs
->event_thread
->step_multi
3177 && ecs
->event_thread
->control
.stop_step
)
3178 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
3181 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3186 /* No error, don't finish the thread states yet. */
3187 discard_cleanups (ts_old_chain
);
3189 /* Revert thread and frame. */
3190 do_cleanups (old_chain
);
3192 /* If the inferior was in sync execution mode, and now isn't,
3193 restore the prompt (a synchronous execution command has finished,
3194 and we're ready for input). */
3195 if (interpreter_async
&& was_sync
&& !sync_execution
)
3196 observer_notify_sync_execution_done ();
3200 && exec_done_display_p
3201 && (ptid_equal (inferior_ptid
, null_ptid
)
3202 || !is_running (inferior_ptid
)))
3203 printf_unfiltered (_("completed.\n"));
3206 /* Record the frame and location we're currently stepping through. */
3208 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3210 struct thread_info
*tp
= inferior_thread ();
3212 tp
->control
.step_frame_id
= get_frame_id (frame
);
3213 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
3215 tp
->current_symtab
= sal
.symtab
;
3216 tp
->current_line
= sal
.line
;
3219 /* Clear context switchable stepping state. */
3222 init_thread_stepping_state (struct thread_info
*tss
)
3224 tss
->stepping_over_breakpoint
= 0;
3225 tss
->stepping_over_watchpoint
= 0;
3226 tss
->step_after_step_resume_breakpoint
= 0;
3229 /* Set the cached copy of the last ptid/waitstatus. */
3232 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
3234 target_last_wait_ptid
= ptid
;
3235 target_last_waitstatus
= status
;
3238 /* Return the cached copy of the last pid/waitstatus returned by
3239 target_wait()/deprecated_target_wait_hook(). The data is actually
3240 cached by handle_inferior_event(), which gets called immediately
3241 after target_wait()/deprecated_target_wait_hook(). */
3244 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
3246 *ptidp
= target_last_wait_ptid
;
3247 *status
= target_last_waitstatus
;
3251 nullify_last_target_wait_ptid (void)
3253 target_last_wait_ptid
= minus_one_ptid
;
3256 /* Switch thread contexts. */
3259 context_switch (ptid_t ptid
)
3261 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
3263 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
3264 target_pid_to_str (inferior_ptid
));
3265 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
3266 target_pid_to_str (ptid
));
3269 switch_to_thread (ptid
);
3273 adjust_pc_after_break (struct execution_control_state
*ecs
)
3275 struct regcache
*regcache
;
3276 struct gdbarch
*gdbarch
;
3277 struct address_space
*aspace
;
3278 CORE_ADDR breakpoint_pc
, decr_pc
;
3280 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
3281 we aren't, just return.
3283 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
3284 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
3285 implemented by software breakpoints should be handled through the normal
3288 NOTE drow/2004-01-31: On some targets, breakpoints may generate
3289 different signals (SIGILL or SIGEMT for instance), but it is less
3290 clear where the PC is pointing afterwards. It may not match
3291 gdbarch_decr_pc_after_break. I don't know any specific target that
3292 generates these signals at breakpoints (the code has been in GDB since at
3293 least 1992) so I can not guess how to handle them here.
3295 In earlier versions of GDB, a target with
3296 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
3297 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
3298 target with both of these set in GDB history, and it seems unlikely to be
3299 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
3301 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
3304 if (ecs
->ws
.value
.sig
!= GDB_SIGNAL_TRAP
)
3307 /* In reverse execution, when a breakpoint is hit, the instruction
3308 under it has already been de-executed. The reported PC always
3309 points at the breakpoint address, so adjusting it further would
3310 be wrong. E.g., consider this case on a decr_pc_after_break == 1
3313 B1 0x08000000 : INSN1
3314 B2 0x08000001 : INSN2
3316 PC -> 0x08000003 : INSN4
3318 Say you're stopped at 0x08000003 as above. Reverse continuing
3319 from that point should hit B2 as below. Reading the PC when the
3320 SIGTRAP is reported should read 0x08000001 and INSN2 should have
3321 been de-executed already.
3323 B1 0x08000000 : INSN1
3324 B2 PC -> 0x08000001 : INSN2
3328 We can't apply the same logic as for forward execution, because
3329 we would wrongly adjust the PC to 0x08000000, since there's a
3330 breakpoint at PC - 1. We'd then report a hit on B1, although
3331 INSN1 hadn't been de-executed yet. Doing nothing is the correct
3333 if (execution_direction
== EXEC_REVERSE
)
3336 /* If this target does not decrement the PC after breakpoints, then
3337 we have nothing to do. */
3338 regcache
= get_thread_regcache (ecs
->ptid
);
3339 gdbarch
= get_regcache_arch (regcache
);
3341 decr_pc
= target_decr_pc_after_break (gdbarch
);
3345 aspace
= get_regcache_aspace (regcache
);
3347 /* Find the location where (if we've hit a breakpoint) the
3348 breakpoint would be. */
3349 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
3351 /* Check whether there actually is a software breakpoint inserted at
3354 If in non-stop mode, a race condition is possible where we've
3355 removed a breakpoint, but stop events for that breakpoint were
3356 already queued and arrive later. To suppress those spurious
3357 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3358 and retire them after a number of stop events are reported. */
3359 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3360 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3362 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
3364 if (record_full_is_used ())
3365 record_full_gdb_operation_disable_set ();
3367 /* When using hardware single-step, a SIGTRAP is reported for both
3368 a completed single-step and a software breakpoint. Need to
3369 differentiate between the two, as the latter needs adjusting
3370 but the former does not.
3372 The SIGTRAP can be due to a completed hardware single-step only if
3373 - we didn't insert software single-step breakpoints
3374 - the thread to be examined is still the current thread
3375 - this thread is currently being stepped
3377 If any of these events did not occur, we must have stopped due
3378 to hitting a software breakpoint, and have to back up to the
3381 As a special case, we could have hardware single-stepped a
3382 software breakpoint. In this case (prev_pc == breakpoint_pc),
3383 we also need to back up to the breakpoint address. */
3385 if (thread_has_single_step_breakpoints_set (ecs
->event_thread
)
3386 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
3387 || !currently_stepping (ecs
->event_thread
)
3388 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
3389 regcache_write_pc (regcache
, breakpoint_pc
);
3391 do_cleanups (old_cleanups
);
3396 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3398 for (frame
= get_prev_frame (frame
);
3400 frame
= get_prev_frame (frame
))
3402 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3404 if (get_frame_type (frame
) != INLINE_FRAME
)
3411 /* Auxiliary function that handles syscall entry/return events.
3412 It returns 1 if the inferior should keep going (and GDB
3413 should ignore the event), or 0 if the event deserves to be
3417 handle_syscall_event (struct execution_control_state
*ecs
)
3419 struct regcache
*regcache
;
3422 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3423 context_switch (ecs
->ptid
);
3425 regcache
= get_thread_regcache (ecs
->ptid
);
3426 syscall_number
= ecs
->ws
.value
.syscall_number
;
3427 stop_pc
= regcache_read_pc (regcache
);
3429 if (catch_syscall_enabled () > 0
3430 && catching_syscall_number (syscall_number
) > 0)
3433 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3436 ecs
->event_thread
->control
.stop_bpstat
3437 = bpstat_stop_status (get_regcache_aspace (regcache
),
3438 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3440 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3442 /* Catchpoint hit. */
3447 /* If no catchpoint triggered for this, then keep going. */
3452 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3455 fill_in_stop_func (struct gdbarch
*gdbarch
,
3456 struct execution_control_state
*ecs
)
3458 if (!ecs
->stop_func_filled_in
)
3460 /* Don't care about return value; stop_func_start and stop_func_name
3461 will both be 0 if it doesn't work. */
3462 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3463 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3464 ecs
->stop_func_start
3465 += gdbarch_deprecated_function_start_offset (gdbarch
);
3467 if (gdbarch_skip_entrypoint_p (gdbarch
))
3468 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
3469 ecs
->stop_func_start
);
3471 ecs
->stop_func_filled_in
= 1;
3476 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
3478 static enum stop_kind
3479 get_inferior_stop_soon (ptid_t ptid
)
3481 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ptid
));
3483 gdb_assert (inf
!= NULL
);
3484 return inf
->control
.stop_soon
;
3487 /* Given an execution control state that has been freshly filled in by
3488 an event from the inferior, figure out what it means and take
3491 The alternatives are:
3493 1) stop_waiting and return; to really stop and return to the
3496 2) keep_going and return; to wait for the next event (set
3497 ecs->event_thread->stepping_over_breakpoint to 1 to single step
3501 handle_inferior_event (struct execution_control_state
*ecs
)
3503 enum stop_kind stop_soon
;
3505 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3507 /* We had an event in the inferior, but we are not interested in
3508 handling it at this level. The lower layers have already
3509 done what needs to be done, if anything.
3511 One of the possible circumstances for this is when the
3512 inferior produces output for the console. The inferior has
3513 not stopped, and we are ignoring the event. Another possible
3514 circumstance is any event which the lower level knows will be
3515 reported multiple times without an intervening resume. */
3517 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3518 prepare_to_wait (ecs
);
3522 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3523 && target_can_async_p () && !sync_execution
)
3525 /* There were no unwaited-for children left in the target, but,
3526 we're not synchronously waiting for events either. Just
3527 ignore. Otherwise, if we were running a synchronous
3528 execution command, we need to cancel it and give the user
3529 back the terminal. */
3531 fprintf_unfiltered (gdb_stdlog
,
3532 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3533 prepare_to_wait (ecs
);
3537 /* Cache the last pid/waitstatus. */
3538 set_last_target_status (ecs
->ptid
, ecs
->ws
);
3540 /* Always clear state belonging to the previous time we stopped. */
3541 stop_stack_dummy
= STOP_NONE
;
3543 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3545 /* No unwaited-for children left. IOW, all resumed children
3548 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3550 stop_print_frame
= 0;
3555 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3556 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
3558 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3559 /* If it's a new thread, add it to the thread database. */
3560 if (ecs
->event_thread
== NULL
)
3561 ecs
->event_thread
= add_thread (ecs
->ptid
);
3563 /* Disable range stepping. If the next step request could use a
3564 range, this will be end up re-enabled then. */
3565 ecs
->event_thread
->control
.may_range_step
= 0;
3568 /* Dependent on valid ECS->EVENT_THREAD. */
3569 adjust_pc_after_break (ecs
);
3571 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3572 reinit_frame_cache ();
3574 breakpoint_retire_moribund ();
3576 /* First, distinguish signals caused by the debugger from signals
3577 that have to do with the program's own actions. Note that
3578 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3579 on the operating system version. Here we detect when a SIGILL or
3580 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3581 something similar for SIGSEGV, since a SIGSEGV will be generated
3582 when we're trying to execute a breakpoint instruction on a
3583 non-executable stack. This happens for call dummy breakpoints
3584 for architectures like SPARC that place call dummies on the
3586 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3587 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3588 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3589 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3591 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3593 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3594 regcache_read_pc (regcache
)))
3597 fprintf_unfiltered (gdb_stdlog
,
3598 "infrun: Treating signal as SIGTRAP\n");
3599 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3603 /* Mark the non-executing threads accordingly. In all-stop, all
3604 threads of all processes are stopped when we get any event
3605 reported. In non-stop mode, only the event thread stops. If
3606 we're handling a process exit in non-stop mode, there's nothing
3607 to do, as threads of the dead process are gone, and threads of
3608 any other process were left running. */
3610 set_executing (minus_one_ptid
, 0);
3611 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3612 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3613 set_executing (ecs
->ptid
, 0);
3615 switch (ecs
->ws
.kind
)
3617 case TARGET_WAITKIND_LOADED
:
3619 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3620 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3621 context_switch (ecs
->ptid
);
3622 /* Ignore gracefully during startup of the inferior, as it might
3623 be the shell which has just loaded some objects, otherwise
3624 add the symbols for the newly loaded objects. Also ignore at
3625 the beginning of an attach or remote session; we will query
3626 the full list of libraries once the connection is
3629 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
3630 if (stop_soon
== NO_STOP_QUIETLY
)
3632 struct regcache
*regcache
;
3634 regcache
= get_thread_regcache (ecs
->ptid
);
3636 handle_solib_event ();
3638 ecs
->event_thread
->control
.stop_bpstat
3639 = bpstat_stop_status (get_regcache_aspace (regcache
),
3640 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3642 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3644 /* A catchpoint triggered. */
3645 process_event_stop_test (ecs
);
3649 /* If requested, stop when the dynamic linker notifies
3650 gdb of events. This allows the user to get control
3651 and place breakpoints in initializer routines for
3652 dynamically loaded objects (among other things). */
3653 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3654 if (stop_on_solib_events
)
3656 /* Make sure we print "Stopped due to solib-event" in
3658 stop_print_frame
= 1;
3665 /* If we are skipping through a shell, or through shared library
3666 loading that we aren't interested in, resume the program. If
3667 we're running the program normally, also resume. */
3668 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3670 /* Loading of shared libraries might have changed breakpoint
3671 addresses. Make sure new breakpoints are inserted. */
3672 if (stop_soon
== NO_STOP_QUIETLY
)
3673 insert_breakpoints ();
3674 resume (0, GDB_SIGNAL_0
);
3675 prepare_to_wait (ecs
);
3679 /* But stop if we're attaching or setting up a remote
3681 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3682 || stop_soon
== STOP_QUIETLY_REMOTE
)
3685 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3690 internal_error (__FILE__
, __LINE__
,
3691 _("unhandled stop_soon: %d"), (int) stop_soon
);
3693 case TARGET_WAITKIND_SPURIOUS
:
3695 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3696 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3697 context_switch (ecs
->ptid
);
3698 resume (0, GDB_SIGNAL_0
);
3699 prepare_to_wait (ecs
);
3702 case TARGET_WAITKIND_EXITED
:
3703 case TARGET_WAITKIND_SIGNALLED
:
3706 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3707 fprintf_unfiltered (gdb_stdlog
,
3708 "infrun: TARGET_WAITKIND_EXITED\n");
3710 fprintf_unfiltered (gdb_stdlog
,
3711 "infrun: TARGET_WAITKIND_SIGNALLED\n");
3714 inferior_ptid
= ecs
->ptid
;
3715 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3716 set_current_program_space (current_inferior ()->pspace
);
3717 handle_vfork_child_exec_or_exit (0);
3718 target_terminal_ours (); /* Must do this before mourn anyway. */
3720 /* Clearing any previous state of convenience variables. */
3721 clear_exit_convenience_vars ();
3723 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3725 /* Record the exit code in the convenience variable $_exitcode, so
3726 that the user can inspect this again later. */
3727 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3728 (LONGEST
) ecs
->ws
.value
.integer
);
3730 /* Also record this in the inferior itself. */
3731 current_inferior ()->has_exit_code
= 1;
3732 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3734 /* Support the --return-child-result option. */
3735 return_child_result_value
= ecs
->ws
.value
.integer
;
3737 observer_notify_exited (ecs
->ws
.value
.integer
);
3741 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3742 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3744 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
3746 /* Set the value of the internal variable $_exitsignal,
3747 which holds the signal uncaught by the inferior. */
3748 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
3749 gdbarch_gdb_signal_to_target (gdbarch
,
3750 ecs
->ws
.value
.sig
));
3754 /* We don't have access to the target's method used for
3755 converting between signal numbers (GDB's internal
3756 representation <-> target's representation).
3757 Therefore, we cannot do a good job at displaying this
3758 information to the user. It's better to just warn
3759 her about it (if infrun debugging is enabled), and
3762 fprintf_filtered (gdb_stdlog
, _("\
3763 Cannot fill $_exitsignal with the correct signal number.\n"));
3766 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
3769 gdb_flush (gdb_stdout
);
3770 target_mourn_inferior ();
3771 stop_print_frame
= 0;
3775 /* The following are the only cases in which we keep going;
3776 the above cases end in a continue or goto. */
3777 case TARGET_WAITKIND_FORKED
:
3778 case TARGET_WAITKIND_VFORKED
:
3781 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3782 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3784 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
3787 /* Check whether the inferior is displaced stepping. */
3789 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3790 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3791 struct displaced_step_inferior_state
*displaced
3792 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3794 /* If checking displaced stepping is supported, and thread
3795 ecs->ptid is displaced stepping. */
3796 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3798 struct inferior
*parent_inf
3799 = find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3800 struct regcache
*child_regcache
;
3801 CORE_ADDR parent_pc
;
3803 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3804 indicating that the displaced stepping of syscall instruction
3805 has been done. Perform cleanup for parent process here. Note
3806 that this operation also cleans up the child process for vfork,
3807 because their pages are shared. */
3808 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
3810 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3812 /* Restore scratch pad for child process. */
3813 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3816 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3817 the child's PC is also within the scratchpad. Set the child's PC
3818 to the parent's PC value, which has already been fixed up.
3819 FIXME: we use the parent's aspace here, although we're touching
3820 the child, because the child hasn't been added to the inferior
3821 list yet at this point. */
3824 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3826 parent_inf
->aspace
);
3827 /* Read PC value of parent process. */
3828 parent_pc
= regcache_read_pc (regcache
);
3830 if (debug_displaced
)
3831 fprintf_unfiltered (gdb_stdlog
,
3832 "displaced: write child pc from %s to %s\n",
3834 regcache_read_pc (child_regcache
)),
3835 paddress (gdbarch
, parent_pc
));
3837 regcache_write_pc (child_regcache
, parent_pc
);
3841 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3842 context_switch (ecs
->ptid
);
3844 /* Immediately detach breakpoints from the child before there's
3845 any chance of letting the user delete breakpoints from the
3846 breakpoint lists. If we don't do this early, it's easy to
3847 leave left over traps in the child, vis: "break foo; catch
3848 fork; c; <fork>; del; c; <child calls foo>". We only follow
3849 the fork on the last `continue', and by that time the
3850 breakpoint at "foo" is long gone from the breakpoint table.
3851 If we vforked, then we don't need to unpatch here, since both
3852 parent and child are sharing the same memory pages; we'll
3853 need to unpatch at follow/detach time instead to be certain
3854 that new breakpoints added between catchpoint hit time and
3855 vfork follow are detached. */
3856 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3858 /* This won't actually modify the breakpoint list, but will
3859 physically remove the breakpoints from the child. */
3860 detach_breakpoints (ecs
->ws
.value
.related_pid
);
3863 delete_just_stopped_threads_single_step_breakpoints ();
3865 /* In case the event is caught by a catchpoint, remember that
3866 the event is to be followed at the next resume of the thread,
3867 and not immediately. */
3868 ecs
->event_thread
->pending_follow
= ecs
->ws
;
3870 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3872 ecs
->event_thread
->control
.stop_bpstat
3873 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3874 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3876 /* If no catchpoint triggered for this, then keep going. Note
3877 that we're interested in knowing the bpstat actually causes a
3878 stop, not just if it may explain the signal. Software
3879 watchpoints, for example, always appear in the bpstat. */
3880 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3886 = (follow_fork_mode_string
== follow_fork_mode_child
);
3888 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3890 should_resume
= follow_fork ();
3893 child
= ecs
->ws
.value
.related_pid
;
3895 /* In non-stop mode, also resume the other branch. */
3896 if (non_stop
&& !detach_fork
)
3899 switch_to_thread (parent
);
3901 switch_to_thread (child
);
3903 ecs
->event_thread
= inferior_thread ();
3904 ecs
->ptid
= inferior_ptid
;
3909 switch_to_thread (child
);
3911 switch_to_thread (parent
);
3913 ecs
->event_thread
= inferior_thread ();
3914 ecs
->ptid
= inferior_ptid
;
3922 process_event_stop_test (ecs
);
3925 case TARGET_WAITKIND_VFORK_DONE
:
3926 /* Done with the shared memory region. Re-insert breakpoints in
3927 the parent, and keep going. */
3930 fprintf_unfiltered (gdb_stdlog
,
3931 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3933 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3934 context_switch (ecs
->ptid
);
3936 current_inferior ()->waiting_for_vfork_done
= 0;
3937 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
3938 /* This also takes care of reinserting breakpoints in the
3939 previously locked inferior. */
3943 case TARGET_WAITKIND_EXECD
:
3945 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
3947 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3948 context_switch (ecs
->ptid
);
3950 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3952 /* Do whatever is necessary to the parent branch of the vfork. */
3953 handle_vfork_child_exec_or_exit (1);
3955 /* This causes the eventpoints and symbol table to be reset.
3956 Must do this now, before trying to determine whether to
3958 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
3960 ecs
->event_thread
->control
.stop_bpstat
3961 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3962 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3964 /* Note that this may be referenced from inside
3965 bpstat_stop_status above, through inferior_has_execd. */
3966 xfree (ecs
->ws
.value
.execd_pathname
);
3967 ecs
->ws
.value
.execd_pathname
= NULL
;
3969 /* If no catchpoint triggered for this, then keep going. */
3970 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3972 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3976 process_event_stop_test (ecs
);
3979 /* Be careful not to try to gather much state about a thread
3980 that's in a syscall. It's frequently a losing proposition. */
3981 case TARGET_WAITKIND_SYSCALL_ENTRY
:
3983 fprintf_unfiltered (gdb_stdlog
,
3984 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3985 /* Getting the current syscall number. */
3986 if (handle_syscall_event (ecs
) == 0)
3987 process_event_stop_test (ecs
);
3990 /* Before examining the threads further, step this thread to
3991 get it entirely out of the syscall. (We get notice of the
3992 event when the thread is just on the verge of exiting a
3993 syscall. Stepping one instruction seems to get it back
3995 case TARGET_WAITKIND_SYSCALL_RETURN
:
3997 fprintf_unfiltered (gdb_stdlog
,
3998 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3999 if (handle_syscall_event (ecs
) == 0)
4000 process_event_stop_test (ecs
);
4003 case TARGET_WAITKIND_STOPPED
:
4005 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
4006 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
4007 handle_signal_stop (ecs
);
4010 case TARGET_WAITKIND_NO_HISTORY
:
4012 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
4013 /* Reverse execution: target ran out of history info. */
4015 delete_just_stopped_threads_single_step_breakpoints ();
4016 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4017 observer_notify_no_history ();
4023 /* Come here when the program has stopped with a signal. */
4026 handle_signal_stop (struct execution_control_state
*ecs
)
4028 struct frame_info
*frame
;
4029 struct gdbarch
*gdbarch
;
4030 int stopped_by_watchpoint
;
4031 enum stop_kind stop_soon
;
4034 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
4036 /* Do we need to clean up the state of a thread that has
4037 completed a displaced single-step? (Doing so usually affects
4038 the PC, so do it here, before we set stop_pc.) */
4039 displaced_step_fixup (ecs
->ptid
,
4040 ecs
->event_thread
->suspend
.stop_signal
);
4042 /* If we either finished a single-step or hit a breakpoint, but
4043 the user wanted this thread to be stopped, pretend we got a
4044 SIG0 (generic unsignaled stop). */
4045 if (ecs
->event_thread
->stop_requested
4046 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4047 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4049 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4053 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4054 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4055 struct cleanup
*old_chain
= save_inferior_ptid ();
4057 inferior_ptid
= ecs
->ptid
;
4059 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
4060 paddress (gdbarch
, stop_pc
));
4061 if (target_stopped_by_watchpoint ())
4065 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
4067 if (target_stopped_data_address (¤t_target
, &addr
))
4068 fprintf_unfiltered (gdb_stdlog
,
4069 "infrun: stopped data address = %s\n",
4070 paddress (gdbarch
, addr
));
4072 fprintf_unfiltered (gdb_stdlog
,
4073 "infrun: (no data address available)\n");
4076 do_cleanups (old_chain
);
4079 /* This is originated from start_remote(), start_inferior() and
4080 shared libraries hook functions. */
4081 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4082 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4084 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4085 context_switch (ecs
->ptid
);
4087 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4088 stop_print_frame
= 1;
4093 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4096 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4097 context_switch (ecs
->ptid
);
4099 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4100 stop_print_frame
= 0;
4105 /* This originates from attach_command(). We need to overwrite
4106 the stop_signal here, because some kernels don't ignore a
4107 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4108 See more comments in inferior.h. On the other hand, if we
4109 get a non-SIGSTOP, report it to the user - assume the backend
4110 will handle the SIGSTOP if it should show up later.
4112 Also consider that the attach is complete when we see a
4113 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4114 target extended-remote report it instead of a SIGSTOP
4115 (e.g. gdbserver). We already rely on SIGTRAP being our
4116 signal, so this is no exception.
4118 Also consider that the attach is complete when we see a
4119 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4120 the target to stop all threads of the inferior, in case the
4121 low level attach operation doesn't stop them implicitly. If
4122 they weren't stopped implicitly, then the stub will report a
4123 GDB_SIGNAL_0, meaning: stopped for no particular reason
4124 other than GDB's request. */
4125 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4126 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
4127 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4128 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
4130 stop_print_frame
= 1;
4132 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4136 /* See if something interesting happened to the non-current thread. If
4137 so, then switch to that thread. */
4138 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4141 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
4143 context_switch (ecs
->ptid
);
4145 if (deprecated_context_hook
)
4146 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
4149 /* At this point, get hold of the now-current thread's frame. */
4150 frame
= get_current_frame ();
4151 gdbarch
= get_frame_arch (frame
);
4153 /* Pull the single step breakpoints out of the target. */
4154 if (gdbarch_software_single_step_p (gdbarch
))
4156 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4158 struct regcache
*regcache
;
4159 struct address_space
*aspace
;
4162 regcache
= get_thread_regcache (ecs
->ptid
);
4163 aspace
= get_regcache_aspace (regcache
);
4164 pc
= regcache_read_pc (regcache
);
4166 /* However, before doing so, if this single-step breakpoint was
4167 actually for another thread, set this thread up for moving
4169 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
4172 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
4176 fprintf_unfiltered (gdb_stdlog
,
4177 "infrun: [%s] hit another thread's "
4178 "single-step breakpoint\n",
4179 target_pid_to_str (ecs
->ptid
));
4181 ecs
->hit_singlestep_breakpoint
= 1;
4188 fprintf_unfiltered (gdb_stdlog
,
4189 "infrun: [%s] hit its "
4190 "single-step breakpoint\n",
4191 target_pid_to_str (ecs
->ptid
));
4196 delete_just_stopped_threads_single_step_breakpoints ();
4199 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4200 && ecs
->event_thread
->control
.trap_expected
4201 && ecs
->event_thread
->stepping_over_watchpoint
)
4202 stopped_by_watchpoint
= 0;
4204 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
4206 /* If necessary, step over this watchpoint. We'll be back to display
4208 if (stopped_by_watchpoint
4209 && (target_have_steppable_watchpoint
4210 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
4212 /* At this point, we are stopped at an instruction which has
4213 attempted to write to a piece of memory under control of
4214 a watchpoint. The instruction hasn't actually executed
4215 yet. If we were to evaluate the watchpoint expression
4216 now, we would get the old value, and therefore no change
4217 would seem to have occurred.
4219 In order to make watchpoints work `right', we really need
4220 to complete the memory write, and then evaluate the
4221 watchpoint expression. We do this by single-stepping the
4224 It may not be necessary to disable the watchpoint to step over
4225 it. For example, the PA can (with some kernel cooperation)
4226 single step over a watchpoint without disabling the watchpoint.
4228 It is far more common to need to disable a watchpoint to step
4229 the inferior over it. If we have non-steppable watchpoints,
4230 we must disable the current watchpoint; it's simplest to
4231 disable all watchpoints.
4233 Any breakpoint at PC must also be stepped over -- if there's
4234 one, it will have already triggered before the watchpoint
4235 triggered, and we either already reported it to the user, or
4236 it didn't cause a stop and we called keep_going. In either
4237 case, if there was a breakpoint at PC, we must be trying to
4239 ecs
->event_thread
->stepping_over_watchpoint
= 1;
4244 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4245 ecs
->event_thread
->stepping_over_watchpoint
= 0;
4246 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4247 ecs
->event_thread
->control
.stop_step
= 0;
4248 stop_print_frame
= 1;
4249 stopped_by_random_signal
= 0;
4251 /* Hide inlined functions starting here, unless we just performed stepi or
4252 nexti. After stepi and nexti, always show the innermost frame (not any
4253 inline function call sites). */
4254 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4256 struct address_space
*aspace
=
4257 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4259 /* skip_inline_frames is expensive, so we avoid it if we can
4260 determine that the address is one where functions cannot have
4261 been inlined. This improves performance with inferiors that
4262 load a lot of shared libraries, because the solib event
4263 breakpoint is defined as the address of a function (i.e. not
4264 inline). Note that we have to check the previous PC as well
4265 as the current one to catch cases when we have just
4266 single-stepped off a breakpoint prior to reinstating it.
4267 Note that we're assuming that the code we single-step to is
4268 not inline, but that's not definitive: there's nothing
4269 preventing the event breakpoint function from containing
4270 inlined code, and the single-step ending up there. If the
4271 user had set a breakpoint on that inlined code, the missing
4272 skip_inline_frames call would break things. Fortunately
4273 that's an extremely unlikely scenario. */
4274 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4275 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4276 && ecs
->event_thread
->control
.trap_expected
4277 && pc_at_non_inline_function (aspace
,
4278 ecs
->event_thread
->prev_pc
,
4281 skip_inline_frames (ecs
->ptid
);
4283 /* Re-fetch current thread's frame in case that invalidated
4285 frame
= get_current_frame ();
4286 gdbarch
= get_frame_arch (frame
);
4290 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4291 && ecs
->event_thread
->control
.trap_expected
4292 && gdbarch_single_step_through_delay_p (gdbarch
)
4293 && currently_stepping (ecs
->event_thread
))
4295 /* We're trying to step off a breakpoint. Turns out that we're
4296 also on an instruction that needs to be stepped multiple
4297 times before it's been fully executing. E.g., architectures
4298 with a delay slot. It needs to be stepped twice, once for
4299 the instruction and once for the delay slot. */
4300 int step_through_delay
4301 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4303 if (debug_infrun
&& step_through_delay
)
4304 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4305 if (ecs
->event_thread
->control
.step_range_end
== 0
4306 && step_through_delay
)
4308 /* The user issued a continue when stopped at a breakpoint.
4309 Set up for another trap and get out of here. */
4310 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4314 else if (step_through_delay
)
4316 /* The user issued a step when stopped at a breakpoint.
4317 Maybe we should stop, maybe we should not - the delay
4318 slot *might* correspond to a line of source. In any
4319 case, don't decide that here, just set
4320 ecs->stepping_over_breakpoint, making sure we
4321 single-step again before breakpoints are re-inserted. */
4322 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4326 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4327 handles this event. */
4328 ecs
->event_thread
->control
.stop_bpstat
4329 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4330 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4332 /* Following in case break condition called a
4334 stop_print_frame
= 1;
4336 /* This is where we handle "moribund" watchpoints. Unlike
4337 software breakpoints traps, hardware watchpoint traps are
4338 always distinguishable from random traps. If no high-level
4339 watchpoint is associated with the reported stop data address
4340 anymore, then the bpstat does not explain the signal ---
4341 simply make sure to ignore it if `stopped_by_watchpoint' is
4345 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4346 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4348 && stopped_by_watchpoint
)
4349 fprintf_unfiltered (gdb_stdlog
,
4350 "infrun: no user watchpoint explains "
4351 "watchpoint SIGTRAP, ignoring\n");
4353 /* NOTE: cagney/2003-03-29: These checks for a random signal
4354 at one stage in the past included checks for an inferior
4355 function call's call dummy's return breakpoint. The original
4356 comment, that went with the test, read:
4358 ``End of a stack dummy. Some systems (e.g. Sony news) give
4359 another signal besides SIGTRAP, so check here as well as
4362 If someone ever tries to get call dummys on a
4363 non-executable stack to work (where the target would stop
4364 with something like a SIGSEGV), then those tests might need
4365 to be re-instated. Given, however, that the tests were only
4366 enabled when momentary breakpoints were not being used, I
4367 suspect that it won't be the case.
4369 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4370 be necessary for call dummies on a non-executable stack on
4373 /* See if the breakpoints module can explain the signal. */
4375 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4376 ecs
->event_thread
->suspend
.stop_signal
);
4378 /* If not, perhaps stepping/nexting can. */
4380 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4381 && currently_stepping (ecs
->event_thread
));
4383 /* Perhaps the thread hit a single-step breakpoint of _another_
4384 thread. Single-step breakpoints are transparent to the
4385 breakpoints module. */
4387 random_signal
= !ecs
->hit_singlestep_breakpoint
;
4389 /* No? Perhaps we got a moribund watchpoint. */
4391 random_signal
= !stopped_by_watchpoint
;
4393 /* For the program's own signals, act according to
4394 the signal handling tables. */
4398 /* Signal not for debugging purposes. */
4399 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
4400 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
4403 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
4404 gdb_signal_to_symbol_string (stop_signal
));
4406 stopped_by_random_signal
= 1;
4408 /* Always stop on signals if we're either just gaining control
4409 of the program, or the user explicitly requested this thread
4410 to remain stopped. */
4411 if (stop_soon
!= NO_STOP_QUIETLY
4412 || ecs
->event_thread
->stop_requested
4414 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4420 /* Notify observers the signal has "handle print" set. Note we
4421 returned early above if stopping; normal_stop handles the
4422 printing in that case. */
4423 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4425 /* The signal table tells us to print about this signal. */
4426 target_terminal_ours_for_output ();
4427 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
4428 target_terminal_inferior ();
4431 /* Clear the signal if it should not be passed. */
4432 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4433 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4435 if (ecs
->event_thread
->prev_pc
== stop_pc
4436 && ecs
->event_thread
->control
.trap_expected
4437 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4439 /* We were just starting a new sequence, attempting to
4440 single-step off of a breakpoint and expecting a SIGTRAP.
4441 Instead this signal arrives. This signal will take us out
4442 of the stepping range so GDB needs to remember to, when
4443 the signal handler returns, resume stepping off that
4445 /* To simplify things, "continue" is forced to use the same
4446 code paths as single-step - set a breakpoint at the
4447 signal return address and then, once hit, step off that
4450 fprintf_unfiltered (gdb_stdlog
,
4451 "infrun: signal arrived while stepping over "
4454 insert_hp_step_resume_breakpoint_at_frame (frame
);
4455 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4456 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4457 ecs
->event_thread
->control
.trap_expected
= 0;
4459 /* If we were nexting/stepping some other thread, switch to
4460 it, so that we don't continue it, losing control. */
4461 if (!switch_back_to_stepped_thread (ecs
))
4466 if (ecs
->event_thread
->control
.step_range_end
!= 0
4467 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4468 && pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4469 && frame_id_eq (get_stack_frame_id (frame
),
4470 ecs
->event_thread
->control
.step_stack_frame_id
)
4471 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4473 /* The inferior is about to take a signal that will take it
4474 out of the single step range. Set a breakpoint at the
4475 current PC (which is presumably where the signal handler
4476 will eventually return) and then allow the inferior to
4479 Note that this is only needed for a signal delivered
4480 while in the single-step range. Nested signals aren't a
4481 problem as they eventually all return. */
4483 fprintf_unfiltered (gdb_stdlog
,
4484 "infrun: signal may take us out of "
4485 "single-step range\n");
4487 insert_hp_step_resume_breakpoint_at_frame (frame
);
4488 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4489 ecs
->event_thread
->control
.trap_expected
= 0;
4494 /* Note: step_resume_breakpoint may be non-NULL. This occures
4495 when either there's a nested signal, or when there's a
4496 pending signal enabled just as the signal handler returns
4497 (leaving the inferior at the step-resume-breakpoint without
4498 actually executing it). Either way continue until the
4499 breakpoint is really hit. */
4501 if (!switch_back_to_stepped_thread (ecs
))
4504 fprintf_unfiltered (gdb_stdlog
,
4505 "infrun: random signal, keep going\n");
4512 process_event_stop_test (ecs
);
4515 /* Come here when we've got some debug event / signal we can explain
4516 (IOW, not a random signal), and test whether it should cause a
4517 stop, or whether we should resume the inferior (transparently).
4518 E.g., could be a breakpoint whose condition evaluates false; we
4519 could be still stepping within the line; etc. */
4522 process_event_stop_test (struct execution_control_state
*ecs
)
4524 struct symtab_and_line stop_pc_sal
;
4525 struct frame_info
*frame
;
4526 struct gdbarch
*gdbarch
;
4527 CORE_ADDR jmp_buf_pc
;
4528 struct bpstat_what what
;
4530 /* Handle cases caused by hitting a breakpoint. */
4532 frame
= get_current_frame ();
4533 gdbarch
= get_frame_arch (frame
);
4535 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4537 if (what
.call_dummy
)
4539 stop_stack_dummy
= what
.call_dummy
;
4542 /* If we hit an internal event that triggers symbol changes, the
4543 current frame will be invalidated within bpstat_what (e.g., if we
4544 hit an internal solib event). Re-fetch it. */
4545 frame
= get_current_frame ();
4546 gdbarch
= get_frame_arch (frame
);
4548 switch (what
.main_action
)
4550 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4551 /* If we hit the breakpoint at longjmp while stepping, we
4552 install a momentary breakpoint at the target of the
4556 fprintf_unfiltered (gdb_stdlog
,
4557 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4559 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4561 if (what
.is_longjmp
)
4563 struct value
*arg_value
;
4565 /* If we set the longjmp breakpoint via a SystemTap probe,
4566 then use it to extract the arguments. The destination PC
4567 is the third argument to the probe. */
4568 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4571 jmp_buf_pc
= value_as_address (arg_value
);
4572 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
4574 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4575 || !gdbarch_get_longjmp_target (gdbarch
,
4576 frame
, &jmp_buf_pc
))
4579 fprintf_unfiltered (gdb_stdlog
,
4580 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4581 "(!gdbarch_get_longjmp_target)\n");
4586 /* Insert a breakpoint at resume address. */
4587 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4590 check_exception_resume (ecs
, frame
);
4594 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4596 struct frame_info
*init_frame
;
4598 /* There are several cases to consider.
4600 1. The initiating frame no longer exists. In this case we
4601 must stop, because the exception or longjmp has gone too
4604 2. The initiating frame exists, and is the same as the
4605 current frame. We stop, because the exception or longjmp
4608 3. The initiating frame exists and is different from the
4609 current frame. This means the exception or longjmp has
4610 been caught beneath the initiating frame, so keep going.
4612 4. longjmp breakpoint has been placed just to protect
4613 against stale dummy frames and user is not interested in
4614 stopping around longjmps. */
4617 fprintf_unfiltered (gdb_stdlog
,
4618 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4620 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4622 delete_exception_resume_breakpoint (ecs
->event_thread
);
4624 if (what
.is_longjmp
)
4626 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
4628 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
4636 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4640 struct frame_id current_id
4641 = get_frame_id (get_current_frame ());
4642 if (frame_id_eq (current_id
,
4643 ecs
->event_thread
->initiating_frame
))
4645 /* Case 2. Fall through. */
4655 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
4657 delete_step_resume_breakpoint (ecs
->event_thread
);
4659 end_stepping_range (ecs
);
4663 case BPSTAT_WHAT_SINGLE
:
4665 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4666 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4667 /* Still need to check other stuff, at least the case where we
4668 are stepping and step out of the right range. */
4671 case BPSTAT_WHAT_STEP_RESUME
:
4673 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4675 delete_step_resume_breakpoint (ecs
->event_thread
);
4676 if (ecs
->event_thread
->control
.proceed_to_finish
4677 && execution_direction
== EXEC_REVERSE
)
4679 struct thread_info
*tp
= ecs
->event_thread
;
4681 /* We are finishing a function in reverse, and just hit the
4682 step-resume breakpoint at the start address of the
4683 function, and we're almost there -- just need to back up
4684 by one more single-step, which should take us back to the
4686 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4690 fill_in_stop_func (gdbarch
, ecs
);
4691 if (stop_pc
== ecs
->stop_func_start
4692 && execution_direction
== EXEC_REVERSE
)
4694 /* We are stepping over a function call in reverse, and just
4695 hit the step-resume breakpoint at the start address of
4696 the function. Go back to single-stepping, which should
4697 take us back to the function call. */
4698 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4704 case BPSTAT_WHAT_STOP_NOISY
:
4706 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4707 stop_print_frame
= 1;
4709 /* Assume the thread stopped for a breapoint. We'll still check
4710 whether a/the breakpoint is there when the thread is next
4712 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4717 case BPSTAT_WHAT_STOP_SILENT
:
4719 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4720 stop_print_frame
= 0;
4722 /* Assume the thread stopped for a breapoint. We'll still check
4723 whether a/the breakpoint is there when the thread is next
4725 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4729 case BPSTAT_WHAT_HP_STEP_RESUME
:
4731 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4733 delete_step_resume_breakpoint (ecs
->event_thread
);
4734 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4736 /* Back when the step-resume breakpoint was inserted, we
4737 were trying to single-step off a breakpoint. Go back to
4739 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4740 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4746 case BPSTAT_WHAT_KEEP_CHECKING
:
4750 /* We come here if we hit a breakpoint but should not stop for it.
4751 Possibly we also were stepping and should stop for that. So fall
4752 through and test for stepping. But, if not stepping, do not
4755 /* In all-stop mode, if we're currently stepping but have stopped in
4756 some other thread, we need to switch back to the stepped thread. */
4757 if (switch_back_to_stepped_thread (ecs
))
4760 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4763 fprintf_unfiltered (gdb_stdlog
,
4764 "infrun: step-resume breakpoint is inserted\n");
4766 /* Having a step-resume breakpoint overrides anything
4767 else having to do with stepping commands until
4768 that breakpoint is reached. */
4773 if (ecs
->event_thread
->control
.step_range_end
== 0)
4776 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4777 /* Likewise if we aren't even stepping. */
4782 /* Re-fetch current thread's frame in case the code above caused
4783 the frame cache to be re-initialized, making our FRAME variable
4784 a dangling pointer. */
4785 frame
= get_current_frame ();
4786 gdbarch
= get_frame_arch (frame
);
4787 fill_in_stop_func (gdbarch
, ecs
);
4789 /* If stepping through a line, keep going if still within it.
4791 Note that step_range_end is the address of the first instruction
4792 beyond the step range, and NOT the address of the last instruction
4795 Note also that during reverse execution, we may be stepping
4796 through a function epilogue and therefore must detect when
4797 the current-frame changes in the middle of a line. */
4799 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4800 && (execution_direction
!= EXEC_REVERSE
4801 || frame_id_eq (get_frame_id (frame
),
4802 ecs
->event_thread
->control
.step_frame_id
)))
4806 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4807 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4808 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4810 /* Tentatively re-enable range stepping; `resume' disables it if
4811 necessary (e.g., if we're stepping over a breakpoint or we
4812 have software watchpoints). */
4813 ecs
->event_thread
->control
.may_range_step
= 1;
4815 /* When stepping backward, stop at beginning of line range
4816 (unless it's the function entry point, in which case
4817 keep going back to the call point). */
4818 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4819 && stop_pc
!= ecs
->stop_func_start
4820 && execution_direction
== EXEC_REVERSE
)
4821 end_stepping_range (ecs
);
4828 /* We stepped out of the stepping range. */
4830 /* If we are stepping at the source level and entered the runtime
4831 loader dynamic symbol resolution code...
4833 EXEC_FORWARD: we keep on single stepping until we exit the run
4834 time loader code and reach the callee's address.
4836 EXEC_REVERSE: we've already executed the callee (backward), and
4837 the runtime loader code is handled just like any other
4838 undebuggable function call. Now we need only keep stepping
4839 backward through the trampoline code, and that's handled further
4840 down, so there is nothing for us to do here. */
4842 if (execution_direction
!= EXEC_REVERSE
4843 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4844 && in_solib_dynsym_resolve_code (stop_pc
))
4846 CORE_ADDR pc_after_resolver
=
4847 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
4850 fprintf_unfiltered (gdb_stdlog
,
4851 "infrun: stepped into dynsym resolve code\n");
4853 if (pc_after_resolver
)
4855 /* Set up a step-resume breakpoint at the address
4856 indicated by SKIP_SOLIB_RESOLVER. */
4857 struct symtab_and_line sr_sal
;
4860 sr_sal
.pc
= pc_after_resolver
;
4861 sr_sal
.pspace
= get_frame_program_space (frame
);
4863 insert_step_resume_breakpoint_at_sal (gdbarch
,
4864 sr_sal
, null_frame_id
);
4871 if (ecs
->event_thread
->control
.step_range_end
!= 1
4872 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4873 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4874 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
4877 fprintf_unfiltered (gdb_stdlog
,
4878 "infrun: stepped into signal trampoline\n");
4879 /* The inferior, while doing a "step" or "next", has ended up in
4880 a signal trampoline (either by a signal being delivered or by
4881 the signal handler returning). Just single-step until the
4882 inferior leaves the trampoline (either by calling the handler
4888 /* If we're in the return path from a shared library trampoline,
4889 we want to proceed through the trampoline when stepping. */
4890 /* macro/2012-04-25: This needs to come before the subroutine
4891 call check below as on some targets return trampolines look
4892 like subroutine calls (MIPS16 return thunks). */
4893 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4894 stop_pc
, ecs
->stop_func_name
)
4895 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
4897 /* Determine where this trampoline returns. */
4898 CORE_ADDR real_stop_pc
;
4900 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4903 fprintf_unfiltered (gdb_stdlog
,
4904 "infrun: stepped into solib return tramp\n");
4906 /* Only proceed through if we know where it's going. */
4909 /* And put the step-breakpoint there and go until there. */
4910 struct symtab_and_line sr_sal
;
4912 init_sal (&sr_sal
); /* initialize to zeroes */
4913 sr_sal
.pc
= real_stop_pc
;
4914 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4915 sr_sal
.pspace
= get_frame_program_space (frame
);
4917 /* Do not specify what the fp should be when we stop since
4918 on some machines the prologue is where the new fp value
4920 insert_step_resume_breakpoint_at_sal (gdbarch
,
4921 sr_sal
, null_frame_id
);
4923 /* Restart without fiddling with the step ranges or
4930 /* Check for subroutine calls. The check for the current frame
4931 equalling the step ID is not necessary - the check of the
4932 previous frame's ID is sufficient - but it is a common case and
4933 cheaper than checking the previous frame's ID.
4935 NOTE: frame_id_eq will never report two invalid frame IDs as
4936 being equal, so to get into this block, both the current and
4937 previous frame must have valid frame IDs. */
4938 /* The outer_frame_id check is a heuristic to detect stepping
4939 through startup code. If we step over an instruction which
4940 sets the stack pointer from an invalid value to a valid value,
4941 we may detect that as a subroutine call from the mythical
4942 "outermost" function. This could be fixed by marking
4943 outermost frames as !stack_p,code_p,special_p. Then the
4944 initial outermost frame, before sp was valid, would
4945 have code_addr == &_start. See the comment in frame_id_eq
4947 if (!frame_id_eq (get_stack_frame_id (frame
),
4948 ecs
->event_thread
->control
.step_stack_frame_id
)
4949 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4950 ecs
->event_thread
->control
.step_stack_frame_id
)
4951 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
4953 || step_start_function
!= find_pc_function (stop_pc
))))
4955 CORE_ADDR real_stop_pc
;
4958 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
4960 if ((ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
4961 || ((ecs
->event_thread
->control
.step_range_end
== 1)
4962 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
4963 ecs
->stop_func_start
)))
4965 /* I presume that step_over_calls is only 0 when we're
4966 supposed to be stepping at the assembly language level
4967 ("stepi"). Just stop. */
4968 /* Also, maybe we just did a "nexti" inside a prolog, so we
4969 thought it was a subroutine call but it was not. Stop as
4971 /* And this works the same backward as frontward. MVS */
4972 end_stepping_range (ecs
);
4976 /* Reverse stepping through solib trampolines. */
4978 if (execution_direction
== EXEC_REVERSE
4979 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
4980 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4981 || (ecs
->stop_func_start
== 0
4982 && in_solib_dynsym_resolve_code (stop_pc
))))
4984 /* Any solib trampoline code can be handled in reverse
4985 by simply continuing to single-step. We have already
4986 executed the solib function (backwards), and a few
4987 steps will take us back through the trampoline to the
4993 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4995 /* We're doing a "next".
4997 Normal (forward) execution: set a breakpoint at the
4998 callee's return address (the address at which the caller
5001 Reverse (backward) execution. set the step-resume
5002 breakpoint at the start of the function that we just
5003 stepped into (backwards), and continue to there. When we
5004 get there, we'll need to single-step back to the caller. */
5006 if (execution_direction
== EXEC_REVERSE
)
5008 /* If we're already at the start of the function, we've either
5009 just stepped backward into a single instruction function,
5010 or stepped back out of a signal handler to the first instruction
5011 of the function. Just keep going, which will single-step back
5013 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
5015 struct symtab_and_line sr_sal
;
5017 /* Normal function call return (static or dynamic). */
5019 sr_sal
.pc
= ecs
->stop_func_start
;
5020 sr_sal
.pspace
= get_frame_program_space (frame
);
5021 insert_step_resume_breakpoint_at_sal (gdbarch
,
5022 sr_sal
, null_frame_id
);
5026 insert_step_resume_breakpoint_at_caller (frame
);
5032 /* If we are in a function call trampoline (a stub between the
5033 calling routine and the real function), locate the real
5034 function. That's what tells us (a) whether we want to step
5035 into it at all, and (b) what prologue we want to run to the
5036 end of, if we do step into it. */
5037 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
5038 if (real_stop_pc
== 0)
5039 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
5040 if (real_stop_pc
!= 0)
5041 ecs
->stop_func_start
= real_stop_pc
;
5043 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
5045 struct symtab_and_line sr_sal
;
5048 sr_sal
.pc
= ecs
->stop_func_start
;
5049 sr_sal
.pspace
= get_frame_program_space (frame
);
5051 insert_step_resume_breakpoint_at_sal (gdbarch
,
5052 sr_sal
, null_frame_id
);
5057 /* If we have line number information for the function we are
5058 thinking of stepping into and the function isn't on the skip
5061 If there are several symtabs at that PC (e.g. with include
5062 files), just want to know whether *any* of them have line
5063 numbers. find_pc_line handles this. */
5065 struct symtab_and_line tmp_sal
;
5067 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5068 if (tmp_sal
.line
!= 0
5069 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
5072 if (execution_direction
== EXEC_REVERSE
)
5073 handle_step_into_function_backward (gdbarch
, ecs
);
5075 handle_step_into_function (gdbarch
, ecs
);
5080 /* If we have no line number and the step-stop-if-no-debug is
5081 set, we stop the step so that the user has a chance to switch
5082 in assembly mode. */
5083 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5084 && step_stop_if_no_debug
)
5086 end_stepping_range (ecs
);
5090 if (execution_direction
== EXEC_REVERSE
)
5092 /* If we're already at the start of the function, we've either just
5093 stepped backward into a single instruction function without line
5094 number info, or stepped back out of a signal handler to the first
5095 instruction of the function without line number info. Just keep
5096 going, which will single-step back to the caller. */
5097 if (ecs
->stop_func_start
!= stop_pc
)
5099 /* Set a breakpoint at callee's start address.
5100 From there we can step once and be back in the caller. */
5101 struct symtab_and_line sr_sal
;
5104 sr_sal
.pc
= ecs
->stop_func_start
;
5105 sr_sal
.pspace
= get_frame_program_space (frame
);
5106 insert_step_resume_breakpoint_at_sal (gdbarch
,
5107 sr_sal
, null_frame_id
);
5111 /* Set a breakpoint at callee's return address (the address
5112 at which the caller will resume). */
5113 insert_step_resume_breakpoint_at_caller (frame
);
5119 /* Reverse stepping through solib trampolines. */
5121 if (execution_direction
== EXEC_REVERSE
5122 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5124 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5125 || (ecs
->stop_func_start
== 0
5126 && in_solib_dynsym_resolve_code (stop_pc
)))
5128 /* Any solib trampoline code can be handled in reverse
5129 by simply continuing to single-step. We have already
5130 executed the solib function (backwards), and a few
5131 steps will take us back through the trampoline to the
5136 else if (in_solib_dynsym_resolve_code (stop_pc
))
5138 /* Stepped backward into the solib dynsym resolver.
5139 Set a breakpoint at its start and continue, then
5140 one more step will take us out. */
5141 struct symtab_and_line sr_sal
;
5144 sr_sal
.pc
= ecs
->stop_func_start
;
5145 sr_sal
.pspace
= get_frame_program_space (frame
);
5146 insert_step_resume_breakpoint_at_sal (gdbarch
,
5147 sr_sal
, null_frame_id
);
5153 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5155 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5156 the trampoline processing logic, however, there are some trampolines
5157 that have no names, so we should do trampoline handling first. */
5158 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5159 && ecs
->stop_func_name
== NULL
5160 && stop_pc_sal
.line
== 0)
5163 fprintf_unfiltered (gdb_stdlog
,
5164 "infrun: stepped into undebuggable function\n");
5166 /* The inferior just stepped into, or returned to, an
5167 undebuggable function (where there is no debugging information
5168 and no line number corresponding to the address where the
5169 inferior stopped). Since we want to skip this kind of code,
5170 we keep going until the inferior returns from this
5171 function - unless the user has asked us not to (via
5172 set step-mode) or we no longer know how to get back
5173 to the call site. */
5174 if (step_stop_if_no_debug
5175 || !frame_id_p (frame_unwind_caller_id (frame
)))
5177 /* If we have no line number and the step-stop-if-no-debug
5178 is set, we stop the step so that the user has a chance to
5179 switch in assembly mode. */
5180 end_stepping_range (ecs
);
5185 /* Set a breakpoint at callee's return address (the address
5186 at which the caller will resume). */
5187 insert_step_resume_breakpoint_at_caller (frame
);
5193 if (ecs
->event_thread
->control
.step_range_end
== 1)
5195 /* It is stepi or nexti. We always want to stop stepping after
5198 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5199 end_stepping_range (ecs
);
5203 if (stop_pc_sal
.line
== 0)
5205 /* We have no line number information. That means to stop
5206 stepping (does this always happen right after one instruction,
5207 when we do "s" in a function with no line numbers,
5208 or can this happen as a result of a return or longjmp?). */
5210 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5211 end_stepping_range (ecs
);
5215 /* Look for "calls" to inlined functions, part one. If the inline
5216 frame machinery detected some skipped call sites, we have entered
5217 a new inline function. */
5219 if (frame_id_eq (get_frame_id (get_current_frame ()),
5220 ecs
->event_thread
->control
.step_frame_id
)
5221 && inline_skipped_frames (ecs
->ptid
))
5223 struct symtab_and_line call_sal
;
5226 fprintf_unfiltered (gdb_stdlog
,
5227 "infrun: stepped into inlined function\n");
5229 find_frame_sal (get_current_frame (), &call_sal
);
5231 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5233 /* For "step", we're going to stop. But if the call site
5234 for this inlined function is on the same source line as
5235 we were previously stepping, go down into the function
5236 first. Otherwise stop at the call site. */
5238 if (call_sal
.line
== ecs
->event_thread
->current_line
5239 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5240 step_into_inline_frame (ecs
->ptid
);
5242 end_stepping_range (ecs
);
5247 /* For "next", we should stop at the call site if it is on a
5248 different source line. Otherwise continue through the
5249 inlined function. */
5250 if (call_sal
.line
== ecs
->event_thread
->current_line
5251 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5254 end_stepping_range (ecs
);
5259 /* Look for "calls" to inlined functions, part two. If we are still
5260 in the same real function we were stepping through, but we have
5261 to go further up to find the exact frame ID, we are stepping
5262 through a more inlined call beyond its call site. */
5264 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5265 && !frame_id_eq (get_frame_id (get_current_frame ()),
5266 ecs
->event_thread
->control
.step_frame_id
)
5267 && stepped_in_from (get_current_frame (),
5268 ecs
->event_thread
->control
.step_frame_id
))
5271 fprintf_unfiltered (gdb_stdlog
,
5272 "infrun: stepping through inlined function\n");
5274 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5277 end_stepping_range (ecs
);
5281 if ((stop_pc
== stop_pc_sal
.pc
)
5282 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5283 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5285 /* We are at the start of a different line. So stop. Note that
5286 we don't stop if we step into the middle of a different line.
5287 That is said to make things like for (;;) statements work
5290 fprintf_unfiltered (gdb_stdlog
,
5291 "infrun: stepped to a different line\n");
5292 end_stepping_range (ecs
);
5296 /* We aren't done stepping.
5298 Optimize by setting the stepping range to the line.
5299 (We might not be in the original line, but if we entered a
5300 new line in mid-statement, we continue stepping. This makes
5301 things like for(;;) statements work better.) */
5303 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5304 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5305 ecs
->event_thread
->control
.may_range_step
= 1;
5306 set_step_info (frame
, stop_pc_sal
);
5309 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5313 /* In all-stop mode, if we're currently stepping but have stopped in
5314 some other thread, we may need to switch back to the stepped
5315 thread. Returns true we set the inferior running, false if we left
5316 it stopped (and the event needs further processing). */
5319 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
5323 struct thread_info
*tp
;
5324 struct thread_info
*stepping_thread
;
5325 struct thread_info
*step_over
;
5327 /* If any thread is blocked on some internal breakpoint, and we
5328 simply need to step over that breakpoint to get it going
5329 again, do that first. */
5331 /* However, if we see an event for the stepping thread, then we
5332 know all other threads have been moved past their breakpoints
5333 already. Let the caller check whether the step is finished,
5334 etc., before deciding to move it past a breakpoint. */
5335 if (ecs
->event_thread
->control
.step_range_end
!= 0)
5338 /* Check if the current thread is blocked on an incomplete
5339 step-over, interrupted by a random signal. */
5340 if (ecs
->event_thread
->control
.trap_expected
5341 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5345 fprintf_unfiltered (gdb_stdlog
,
5346 "infrun: need to finish step-over of [%s]\n",
5347 target_pid_to_str (ecs
->event_thread
->ptid
));
5353 /* Check if the current thread is blocked by a single-step
5354 breakpoint of another thread. */
5355 if (ecs
->hit_singlestep_breakpoint
)
5359 fprintf_unfiltered (gdb_stdlog
,
5360 "infrun: need to step [%s] over single-step "
5362 target_pid_to_str (ecs
->ptid
));
5368 /* Otherwise, we no longer expect a trap in the current thread.
5369 Clear the trap_expected flag before switching back -- this is
5370 what keep_going does as well, if we call it. */
5371 ecs
->event_thread
->control
.trap_expected
= 0;
5373 /* Likewise, clear the signal if it should not be passed. */
5374 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5375 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5377 /* If scheduler locking applies even if not stepping, there's no
5378 need to walk over threads. Above we've checked whether the
5379 current thread is stepping. If some other thread not the
5380 event thread is stepping, then it must be that scheduler
5381 locking is not in effect. */
5382 if (schedlock_applies (0))
5385 /* Look for the stepping/nexting thread, and check if any other
5386 thread other than the stepping thread needs to start a
5387 step-over. Do all step-overs before actually proceeding with
5389 stepping_thread
= NULL
;
5391 ALL_NON_EXITED_THREADS (tp
)
5393 /* Ignore threads of processes we're not resuming. */
5395 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (inferior_ptid
))
5398 /* When stepping over a breakpoint, we lock all threads
5399 except the one that needs to move past the breakpoint.
5400 If a non-event thread has this set, the "incomplete
5401 step-over" check above should have caught it earlier. */
5402 gdb_assert (!tp
->control
.trap_expected
);
5404 /* Did we find the stepping thread? */
5405 if (tp
->control
.step_range_end
)
5407 /* Yep. There should only one though. */
5408 gdb_assert (stepping_thread
== NULL
);
5410 /* The event thread is handled at the top, before we
5412 gdb_assert (tp
!= ecs
->event_thread
);
5414 /* If some thread other than the event thread is
5415 stepping, then scheduler locking can't be in effect,
5416 otherwise we wouldn't have resumed the current event
5417 thread in the first place. */
5418 gdb_assert (!schedlock_applies (1));
5420 stepping_thread
= tp
;
5422 else if (thread_still_needs_step_over (tp
))
5426 /* At the top we've returned early if the event thread
5427 is stepping. If some other thread not the event
5428 thread is stepping, then scheduler locking can't be
5429 in effect, and we can resume this thread. No need to
5430 keep looking for the stepping thread then. */
5435 if (step_over
!= NULL
)
5440 fprintf_unfiltered (gdb_stdlog
,
5441 "infrun: need to step-over [%s]\n",
5442 target_pid_to_str (tp
->ptid
));
5445 /* Only the stepping thread should have this set. */
5446 gdb_assert (tp
->control
.step_range_end
== 0);
5448 ecs
->ptid
= tp
->ptid
;
5449 ecs
->event_thread
= tp
;
5450 switch_to_thread (ecs
->ptid
);
5455 if (stepping_thread
!= NULL
)
5457 struct frame_info
*frame
;
5458 struct gdbarch
*gdbarch
;
5460 tp
= stepping_thread
;
5462 /* If the stepping thread exited, then don't try to switch
5463 back and resume it, which could fail in several different
5464 ways depending on the target. Instead, just keep going.
5466 We can find a stepping dead thread in the thread list in
5469 - The target supports thread exit events, and when the
5470 target tries to delete the thread from the thread list,
5471 inferior_ptid pointed at the exiting thread. In such
5472 case, calling delete_thread does not really remove the
5473 thread from the list; instead, the thread is left listed,
5474 with 'exited' state.
5476 - The target's debug interface does not support thread
5477 exit events, and so we have no idea whatsoever if the
5478 previously stepping thread is still alive. For that
5479 reason, we need to synchronously query the target
5481 if (is_exited (tp
->ptid
)
5482 || !target_thread_alive (tp
->ptid
))
5485 fprintf_unfiltered (gdb_stdlog
,
5486 "infrun: not switching back to "
5487 "stepped thread, it has vanished\n");
5489 delete_thread (tp
->ptid
);
5495 fprintf_unfiltered (gdb_stdlog
,
5496 "infrun: switching back to stepped thread\n");
5498 ecs
->event_thread
= tp
;
5499 ecs
->ptid
= tp
->ptid
;
5500 context_switch (ecs
->ptid
);
5502 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5503 frame
= get_current_frame ();
5504 gdbarch
= get_frame_arch (frame
);
5506 /* If the PC of the thread we were trying to single-step has
5507 changed, then that thread has trapped or been signaled,
5508 but the event has not been reported to GDB yet. Re-poll
5509 the target looking for this particular thread's event
5510 (i.e. temporarily enable schedlock) by:
5512 - setting a break at the current PC
5513 - resuming that particular thread, only (by setting
5516 This prevents us continuously moving the single-step
5517 breakpoint forward, one instruction at a time,
5520 if (gdbarch_software_single_step_p (gdbarch
)
5521 && stop_pc
!= tp
->prev_pc
)
5524 fprintf_unfiltered (gdb_stdlog
,
5525 "infrun: expected thread advanced also\n");
5527 /* Clear the info of the previous step-over, as it's no
5528 longer valid. It's what keep_going would do too, if
5529 we called it. Must do this before trying to insert
5530 the sss breakpoint, otherwise if we were previously
5531 trying to step over this exact address in another
5532 thread, the breakpoint ends up not installed. */
5533 clear_step_over_info ();
5535 insert_single_step_breakpoint (get_frame_arch (frame
),
5536 get_frame_address_space (frame
),
5538 ecs
->event_thread
->control
.trap_expected
= 1;
5540 resume (0, GDB_SIGNAL_0
);
5541 prepare_to_wait (ecs
);
5546 fprintf_unfiltered (gdb_stdlog
,
5547 "infrun: expected thread still "
5548 "hasn't advanced\n");
5558 /* Is thread TP in the middle of single-stepping? */
5561 currently_stepping (struct thread_info
*tp
)
5563 return ((tp
->control
.step_range_end
5564 && tp
->control
.step_resume_breakpoint
== NULL
)
5565 || tp
->control
.trap_expected
5566 || bpstat_should_step ());
5569 /* Inferior has stepped into a subroutine call with source code that
5570 we should not step over. Do step to the first line of code in
5574 handle_step_into_function (struct gdbarch
*gdbarch
,
5575 struct execution_control_state
*ecs
)
5578 struct symtab_and_line stop_func_sal
, sr_sal
;
5580 fill_in_stop_func (gdbarch
, ecs
);
5582 s
= find_pc_symtab (stop_pc
);
5583 if (s
&& s
->language
!= language_asm
)
5584 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5585 ecs
->stop_func_start
);
5587 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5588 /* Use the step_resume_break to step until the end of the prologue,
5589 even if that involves jumps (as it seems to on the vax under
5591 /* If the prologue ends in the middle of a source line, continue to
5592 the end of that source line (if it is still within the function).
5593 Otherwise, just go to end of prologue. */
5594 if (stop_func_sal
.end
5595 && stop_func_sal
.pc
!= ecs
->stop_func_start
5596 && stop_func_sal
.end
< ecs
->stop_func_end
)
5597 ecs
->stop_func_start
= stop_func_sal
.end
;
5599 /* Architectures which require breakpoint adjustment might not be able
5600 to place a breakpoint at the computed address. If so, the test
5601 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5602 ecs->stop_func_start to an address at which a breakpoint may be
5603 legitimately placed.
5605 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5606 made, GDB will enter an infinite loop when stepping through
5607 optimized code consisting of VLIW instructions which contain
5608 subinstructions corresponding to different source lines. On
5609 FR-V, it's not permitted to place a breakpoint on any but the
5610 first subinstruction of a VLIW instruction. When a breakpoint is
5611 set, GDB will adjust the breakpoint address to the beginning of
5612 the VLIW instruction. Thus, we need to make the corresponding
5613 adjustment here when computing the stop address. */
5615 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5617 ecs
->stop_func_start
5618 = gdbarch_adjust_breakpoint_address (gdbarch
,
5619 ecs
->stop_func_start
);
5622 if (ecs
->stop_func_start
== stop_pc
)
5624 /* We are already there: stop now. */
5625 end_stepping_range (ecs
);
5630 /* Put the step-breakpoint there and go until there. */
5631 init_sal (&sr_sal
); /* initialize to zeroes */
5632 sr_sal
.pc
= ecs
->stop_func_start
;
5633 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5634 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5636 /* Do not specify what the fp should be when we stop since on
5637 some machines the prologue is where the new fp value is
5639 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5641 /* And make sure stepping stops right away then. */
5642 ecs
->event_thread
->control
.step_range_end
5643 = ecs
->event_thread
->control
.step_range_start
;
5648 /* Inferior has stepped backward into a subroutine call with source
5649 code that we should not step over. Do step to the beginning of the
5650 last line of code in it. */
5653 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5654 struct execution_control_state
*ecs
)
5657 struct symtab_and_line stop_func_sal
;
5659 fill_in_stop_func (gdbarch
, ecs
);
5661 s
= find_pc_symtab (stop_pc
);
5662 if (s
&& s
->language
!= language_asm
)
5663 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5664 ecs
->stop_func_start
);
5666 stop_func_sal
= find_pc_line (stop_pc
, 0);
5668 /* OK, we're just going to keep stepping here. */
5669 if (stop_func_sal
.pc
== stop_pc
)
5671 /* We're there already. Just stop stepping now. */
5672 end_stepping_range (ecs
);
5676 /* Else just reset the step range and keep going.
5677 No step-resume breakpoint, they don't work for
5678 epilogues, which can have multiple entry paths. */
5679 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5680 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5686 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5687 This is used to both functions and to skip over code. */
5690 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5691 struct symtab_and_line sr_sal
,
5692 struct frame_id sr_id
,
5693 enum bptype sr_type
)
5695 /* There should never be more than one step-resume or longjmp-resume
5696 breakpoint per thread, so we should never be setting a new
5697 step_resume_breakpoint when one is already active. */
5698 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5699 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5702 fprintf_unfiltered (gdb_stdlog
,
5703 "infrun: inserting step-resume breakpoint at %s\n",
5704 paddress (gdbarch
, sr_sal
.pc
));
5706 inferior_thread ()->control
.step_resume_breakpoint
5707 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5711 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5712 struct symtab_and_line sr_sal
,
5713 struct frame_id sr_id
)
5715 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5720 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5721 This is used to skip a potential signal handler.
5723 This is called with the interrupted function's frame. The signal
5724 handler, when it returns, will resume the interrupted function at
5728 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5730 struct symtab_and_line sr_sal
;
5731 struct gdbarch
*gdbarch
;
5733 gdb_assert (return_frame
!= NULL
);
5734 init_sal (&sr_sal
); /* initialize to zeros */
5736 gdbarch
= get_frame_arch (return_frame
);
5737 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5738 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5739 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5741 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5742 get_stack_frame_id (return_frame
),
5746 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5747 is used to skip a function after stepping into it (for "next" or if
5748 the called function has no debugging information).
5750 The current function has almost always been reached by single
5751 stepping a call or return instruction. NEXT_FRAME belongs to the
5752 current function, and the breakpoint will be set at the caller's
5755 This is a separate function rather than reusing
5756 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5757 get_prev_frame, which may stop prematurely (see the implementation
5758 of frame_unwind_caller_id for an example). */
5761 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5763 struct symtab_and_line sr_sal
;
5764 struct gdbarch
*gdbarch
;
5766 /* We shouldn't have gotten here if we don't know where the call site
5768 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5770 init_sal (&sr_sal
); /* initialize to zeros */
5772 gdbarch
= frame_unwind_caller_arch (next_frame
);
5773 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5774 frame_unwind_caller_pc (next_frame
));
5775 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5776 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5778 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5779 frame_unwind_caller_id (next_frame
));
5782 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5783 new breakpoint at the target of a jmp_buf. The handling of
5784 longjmp-resume uses the same mechanisms used for handling
5785 "step-resume" breakpoints. */
5788 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5790 /* There should never be more than one longjmp-resume breakpoint per
5791 thread, so we should never be setting a new
5792 longjmp_resume_breakpoint when one is already active. */
5793 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
5796 fprintf_unfiltered (gdb_stdlog
,
5797 "infrun: inserting longjmp-resume breakpoint at %s\n",
5798 paddress (gdbarch
, pc
));
5800 inferior_thread ()->control
.exception_resume_breakpoint
=
5801 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5804 /* Insert an exception resume breakpoint. TP is the thread throwing
5805 the exception. The block B is the block of the unwinder debug hook
5806 function. FRAME is the frame corresponding to the call to this
5807 function. SYM is the symbol of the function argument holding the
5808 target PC of the exception. */
5811 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5812 const struct block
*b
,
5813 struct frame_info
*frame
,
5816 volatile struct gdb_exception e
;
5818 /* We want to ignore errors here. */
5819 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5821 struct symbol
*vsym
;
5822 struct value
*value
;
5824 struct breakpoint
*bp
;
5826 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5827 value
= read_var_value (vsym
, frame
);
5828 /* If the value was optimized out, revert to the old behavior. */
5829 if (! value_optimized_out (value
))
5831 handler
= value_as_address (value
);
5834 fprintf_unfiltered (gdb_stdlog
,
5835 "infrun: exception resume at %lx\n",
5836 (unsigned long) handler
);
5838 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5839 handler
, bp_exception_resume
);
5841 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5844 bp
->thread
= tp
->num
;
5845 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5850 /* A helper for check_exception_resume that sets an
5851 exception-breakpoint based on a SystemTap probe. */
5854 insert_exception_resume_from_probe (struct thread_info
*tp
,
5855 const struct bound_probe
*probe
,
5856 struct frame_info
*frame
)
5858 struct value
*arg_value
;
5860 struct breakpoint
*bp
;
5862 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
5866 handler
= value_as_address (arg_value
);
5869 fprintf_unfiltered (gdb_stdlog
,
5870 "infrun: exception resume at %s\n",
5871 paddress (get_objfile_arch (probe
->objfile
),
5874 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5875 handler
, bp_exception_resume
);
5876 bp
->thread
= tp
->num
;
5877 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5880 /* This is called when an exception has been intercepted. Check to
5881 see whether the exception's destination is of interest, and if so,
5882 set an exception resume breakpoint there. */
5885 check_exception_resume (struct execution_control_state
*ecs
,
5886 struct frame_info
*frame
)
5888 volatile struct gdb_exception e
;
5889 struct bound_probe probe
;
5890 struct symbol
*func
;
5892 /* First see if this exception unwinding breakpoint was set via a
5893 SystemTap probe point. If so, the probe has two arguments: the
5894 CFA and the HANDLER. We ignore the CFA, extract the handler, and
5895 set a breakpoint there. */
5896 probe
= find_probe_by_pc (get_frame_pc (frame
));
5899 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
5903 func
= get_frame_function (frame
);
5907 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5909 const struct block
*b
;
5910 struct block_iterator iter
;
5914 /* The exception breakpoint is a thread-specific breakpoint on
5915 the unwinder's debug hook, declared as:
5917 void _Unwind_DebugHook (void *cfa, void *handler);
5919 The CFA argument indicates the frame to which control is
5920 about to be transferred. HANDLER is the destination PC.
5922 We ignore the CFA and set a temporary breakpoint at HANDLER.
5923 This is not extremely efficient but it avoids issues in gdb
5924 with computing the DWARF CFA, and it also works even in weird
5925 cases such as throwing an exception from inside a signal
5928 b
= SYMBOL_BLOCK_VALUE (func
);
5929 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
5931 if (!SYMBOL_IS_ARGUMENT (sym
))
5938 insert_exception_resume_breakpoint (ecs
->event_thread
,
5947 stop_waiting (struct execution_control_state
*ecs
)
5950 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
5952 clear_step_over_info ();
5954 /* Let callers know we don't want to wait for the inferior anymore. */
5955 ecs
->wait_some_more
= 0;
5958 /* Called when we should continue running the inferior, because the
5959 current event doesn't cause a user visible stop. This does the
5960 resuming part; waiting for the next event is done elsewhere. */
5963 keep_going (struct execution_control_state
*ecs
)
5965 /* Make sure normal_stop is called if we get a QUIT handled before
5967 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
5969 /* Save the pc before execution, to compare with pc after stop. */
5970 ecs
->event_thread
->prev_pc
5971 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5973 if (ecs
->event_thread
->control
.trap_expected
5974 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5976 /* We haven't yet gotten our trap, and either: intercepted a
5977 non-signal event (e.g., a fork); or took a signal which we
5978 are supposed to pass through to the inferior. Simply
5980 discard_cleanups (old_cleanups
);
5981 resume (currently_stepping (ecs
->event_thread
),
5982 ecs
->event_thread
->suspend
.stop_signal
);
5986 volatile struct gdb_exception e
;
5987 struct regcache
*regcache
= get_current_regcache ();
5991 /* Either the trap was not expected, but we are continuing
5992 anyway (if we got a signal, the user asked it be passed to
5995 We got our expected trap, but decided we should resume from
5998 We're going to run this baby now!
6000 Note that insert_breakpoints won't try to re-insert
6001 already inserted breakpoints. Therefore, we don't
6002 care if breakpoints were already inserted, or not. */
6004 /* If we need to step over a breakpoint, and we're not using
6005 displaced stepping to do so, insert all breakpoints
6006 (watchpoints, etc.) but the one we're stepping over, step one
6007 instruction, and then re-insert the breakpoint when that step
6010 remove_bp
= (ecs
->hit_singlestep_breakpoint
6011 || thread_still_needs_step_over (ecs
->event_thread
));
6012 remove_wps
= (ecs
->event_thread
->stepping_over_watchpoint
6013 && !target_have_steppable_watchpoint
);
6015 if (remove_bp
&& !use_displaced_stepping (get_regcache_arch (regcache
)))
6017 set_step_over_info (get_regcache_aspace (regcache
),
6018 regcache_read_pc (regcache
), remove_wps
);
6020 else if (remove_wps
)
6021 set_step_over_info (NULL
, 0, remove_wps
);
6023 clear_step_over_info ();
6025 /* Stop stepping if inserting breakpoints fails. */
6026 TRY_CATCH (e
, RETURN_MASK_ERROR
)
6028 insert_breakpoints ();
6032 exception_print (gdb_stderr
, e
);
6037 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
6039 /* Do not deliver GDB_SIGNAL_TRAP (except when the user
6040 explicitly specifies that such a signal should be delivered
6041 to the target program). Typically, that would occur when a
6042 user is debugging a target monitor on a simulator: the target
6043 monitor sets a breakpoint; the simulator encounters this
6044 breakpoint and halts the simulation handing control to GDB;
6045 GDB, noting that the stop address doesn't map to any known
6046 breakpoint, returns control back to the simulator; the
6047 simulator then delivers the hardware equivalent of a
6048 GDB_SIGNAL_TRAP to the program being debugged. */
6049 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6050 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6051 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6053 discard_cleanups (old_cleanups
);
6054 resume (currently_stepping (ecs
->event_thread
),
6055 ecs
->event_thread
->suspend
.stop_signal
);
6058 prepare_to_wait (ecs
);
6061 /* This function normally comes after a resume, before
6062 handle_inferior_event exits. It takes care of any last bits of
6063 housekeeping, and sets the all-important wait_some_more flag. */
6066 prepare_to_wait (struct execution_control_state
*ecs
)
6069 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
6071 /* This is the old end of the while loop. Let everybody know we
6072 want to wait for the inferior some more and get called again
6074 ecs
->wait_some_more
= 1;
6077 /* We are done with the step range of a step/next/si/ni command.
6078 Called once for each n of a "step n" operation. */
6081 end_stepping_range (struct execution_control_state
*ecs
)
6083 ecs
->event_thread
->control
.stop_step
= 1;
6087 /* Several print_*_reason functions to print why the inferior has stopped.
6088 We always print something when the inferior exits, or receives a signal.
6089 The rest of the cases are dealt with later on in normal_stop and
6090 print_it_typical. Ideally there should be a call to one of these
6091 print_*_reason functions functions from handle_inferior_event each time
6092 stop_waiting is called.
6094 Note that we don't call these directly, instead we delegate that to
6095 the interpreters, through observers. Interpreters then call these
6096 with whatever uiout is right. */
6099 print_end_stepping_range_reason (struct ui_out
*uiout
)
6101 /* For CLI-like interpreters, print nothing. */
6103 if (ui_out_is_mi_like_p (uiout
))
6105 ui_out_field_string (uiout
, "reason",
6106 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
6111 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
6113 annotate_signalled ();
6114 if (ui_out_is_mi_like_p (uiout
))
6116 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
6117 ui_out_text (uiout
, "\nProgram terminated with signal ");
6118 annotate_signal_name ();
6119 ui_out_field_string (uiout
, "signal-name",
6120 gdb_signal_to_name (siggnal
));
6121 annotate_signal_name_end ();
6122 ui_out_text (uiout
, ", ");
6123 annotate_signal_string ();
6124 ui_out_field_string (uiout
, "signal-meaning",
6125 gdb_signal_to_string (siggnal
));
6126 annotate_signal_string_end ();
6127 ui_out_text (uiout
, ".\n");
6128 ui_out_text (uiout
, "The program no longer exists.\n");
6132 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
6134 struct inferior
*inf
= current_inferior ();
6135 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
6137 annotate_exited (exitstatus
);
6140 if (ui_out_is_mi_like_p (uiout
))
6141 ui_out_field_string (uiout
, "reason",
6142 async_reason_lookup (EXEC_ASYNC_EXITED
));
6143 ui_out_text (uiout
, "[Inferior ");
6144 ui_out_text (uiout
, plongest (inf
->num
));
6145 ui_out_text (uiout
, " (");
6146 ui_out_text (uiout
, pidstr
);
6147 ui_out_text (uiout
, ") exited with code ");
6148 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
6149 ui_out_text (uiout
, "]\n");
6153 if (ui_out_is_mi_like_p (uiout
))
6155 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
6156 ui_out_text (uiout
, "[Inferior ");
6157 ui_out_text (uiout
, plongest (inf
->num
));
6158 ui_out_text (uiout
, " (");
6159 ui_out_text (uiout
, pidstr
);
6160 ui_out_text (uiout
, ") exited normally]\n");
6165 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
6169 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
6171 struct thread_info
*t
= inferior_thread ();
6173 ui_out_text (uiout
, "\n[");
6174 ui_out_field_string (uiout
, "thread-name",
6175 target_pid_to_str (t
->ptid
));
6176 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
6177 ui_out_text (uiout
, " stopped");
6181 ui_out_text (uiout
, "\nProgram received signal ");
6182 annotate_signal_name ();
6183 if (ui_out_is_mi_like_p (uiout
))
6185 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
6186 ui_out_field_string (uiout
, "signal-name",
6187 gdb_signal_to_name (siggnal
));
6188 annotate_signal_name_end ();
6189 ui_out_text (uiout
, ", ");
6190 annotate_signal_string ();
6191 ui_out_field_string (uiout
, "signal-meaning",
6192 gdb_signal_to_string (siggnal
));
6193 annotate_signal_string_end ();
6195 ui_out_text (uiout
, ".\n");
6199 print_no_history_reason (struct ui_out
*uiout
)
6201 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
6204 /* Print current location without a level number, if we have changed
6205 functions or hit a breakpoint. Print source line if we have one.
6206 bpstat_print contains the logic deciding in detail what to print,
6207 based on the event(s) that just occurred. */
6210 print_stop_event (struct target_waitstatus
*ws
)
6214 int do_frame_printing
= 1;
6215 struct thread_info
*tp
= inferior_thread ();
6217 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
6221 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
6222 should) carry around the function and does (or should) use
6223 that when doing a frame comparison. */
6224 if (tp
->control
.stop_step
6225 && frame_id_eq (tp
->control
.step_frame_id
,
6226 get_frame_id (get_current_frame ()))
6227 && step_start_function
== find_pc_function (stop_pc
))
6229 /* Finished step, just print source line. */
6230 source_flag
= SRC_LINE
;
6234 /* Print location and source line. */
6235 source_flag
= SRC_AND_LOC
;
6238 case PRINT_SRC_AND_LOC
:
6239 /* Print location and source line. */
6240 source_flag
= SRC_AND_LOC
;
6242 case PRINT_SRC_ONLY
:
6243 source_flag
= SRC_LINE
;
6246 /* Something bogus. */
6247 source_flag
= SRC_LINE
;
6248 do_frame_printing
= 0;
6251 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6254 /* The behavior of this routine with respect to the source
6256 SRC_LINE: Print only source line
6257 LOCATION: Print only location
6258 SRC_AND_LOC: Print location and source line. */
6259 if (do_frame_printing
)
6260 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
6262 /* Display the auto-display expressions. */
6266 /* Here to return control to GDB when the inferior stops for real.
6267 Print appropriate messages, remove breakpoints, give terminal our modes.
6269 STOP_PRINT_FRAME nonzero means print the executing frame
6270 (pc, function, args, file, line number and line text).
6271 BREAKPOINTS_FAILED nonzero means stop was due to error
6272 attempting to insert breakpoints. */
6277 struct target_waitstatus last
;
6279 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
6281 get_last_target_status (&last_ptid
, &last
);
6283 /* If an exception is thrown from this point on, make sure to
6284 propagate GDB's knowledge of the executing state to the
6285 frontend/user running state. A QUIT is an easy exception to see
6286 here, so do this before any filtered output. */
6288 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
6289 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6290 && last
.kind
!= TARGET_WAITKIND_EXITED
6291 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6292 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
6294 /* As we're presenting a stop, and potentially removing breakpoints,
6295 update the thread list so we can tell whether there are threads
6296 running on the target. With target remote, for example, we can
6297 only learn about new threads when we explicitly update the thread
6298 list. Do this before notifying the interpreters about signal
6299 stops, end of stepping ranges, etc., so that the "new thread"
6300 output is emitted before e.g., "Program received signal FOO",
6301 instead of after. */
6302 update_thread_list ();
6304 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
6305 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
6307 /* As with the notification of thread events, we want to delay
6308 notifying the user that we've switched thread context until
6309 the inferior actually stops.
6311 There's no point in saying anything if the inferior has exited.
6312 Note that SIGNALLED here means "exited with a signal", not
6313 "received a signal".
6315 Also skip saying anything in non-stop mode. In that mode, as we
6316 don't want GDB to switch threads behind the user's back, to avoid
6317 races where the user is typing a command to apply to thread x,
6318 but GDB switches to thread y before the user finishes entering
6319 the command, fetch_inferior_event installs a cleanup to restore
6320 the current thread back to the thread the user had selected right
6321 after this event is handled, so we're not really switching, only
6322 informing of a stop. */
6324 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
6325 && target_has_execution
6326 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6327 && last
.kind
!= TARGET_WAITKIND_EXITED
6328 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6330 target_terminal_ours_for_output ();
6331 printf_filtered (_("[Switching to %s]\n"),
6332 target_pid_to_str (inferior_ptid
));
6333 annotate_thread_changed ();
6334 previous_inferior_ptid
= inferior_ptid
;
6337 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
6339 gdb_assert (sync_execution
|| !target_can_async_p ());
6341 target_terminal_ours_for_output ();
6342 printf_filtered (_("No unwaited-for children left.\n"));
6345 /* Note: this depends on the update_thread_list call above. */
6346 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
6348 if (remove_breakpoints ())
6350 target_terminal_ours_for_output ();
6351 printf_filtered (_("Cannot remove breakpoints because "
6352 "program is no longer writable.\nFurther "
6353 "execution is probably impossible.\n"));
6357 /* If an auto-display called a function and that got a signal,
6358 delete that auto-display to avoid an infinite recursion. */
6360 if (stopped_by_random_signal
)
6361 disable_current_display ();
6363 /* Notify observers if we finished a "step"-like command, etc. */
6364 if (target_has_execution
6365 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6366 && last
.kind
!= TARGET_WAITKIND_EXITED
6367 && inferior_thread ()->control
.stop_step
)
6369 /* But not if in the middle of doing a "step n" operation for
6371 if (inferior_thread ()->step_multi
)
6374 observer_notify_end_stepping_range ();
6377 target_terminal_ours ();
6378 async_enable_stdin ();
6380 /* Set the current source location. This will also happen if we
6381 display the frame below, but the current SAL will be incorrect
6382 during a user hook-stop function. */
6383 if (has_stack_frames () && !stop_stack_dummy
)
6384 set_current_sal_from_frame (get_current_frame ());
6386 /* Let the user/frontend see the threads as stopped, but do nothing
6387 if the thread was running an infcall. We may be e.g., evaluating
6388 a breakpoint condition. In that case, the thread had state
6389 THREAD_RUNNING before the infcall, and shall remain set to
6390 running, all without informing the user/frontend about state
6391 transition changes. If this is actually a call command, then the
6392 thread was originally already stopped, so there's no state to
6394 if (target_has_execution
&& inferior_thread ()->control
.in_infcall
)
6395 discard_cleanups (old_chain
);
6397 do_cleanups (old_chain
);
6399 /* Look up the hook_stop and run it (CLI internally handles problem
6400 of stop_command's pre-hook not existing). */
6402 catch_errors (hook_stop_stub
, stop_command
,
6403 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
6405 if (!has_stack_frames ())
6408 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
6409 || last
.kind
== TARGET_WAITKIND_EXITED
)
6412 /* Select innermost stack frame - i.e., current frame is frame 0,
6413 and current location is based on that.
6414 Don't do this on return from a stack dummy routine,
6415 or if the program has exited. */
6417 if (!stop_stack_dummy
)
6419 select_frame (get_current_frame ());
6421 /* If --batch-silent is enabled then there's no need to print the current
6422 source location, and to try risks causing an error message about
6423 missing source files. */
6424 if (stop_print_frame
&& !batch_silent
)
6425 print_stop_event (&last
);
6428 /* Save the function value return registers, if we care.
6429 We might be about to restore their previous contents. */
6430 if (inferior_thread ()->control
.proceed_to_finish
6431 && execution_direction
!= EXEC_REVERSE
)
6433 /* This should not be necessary. */
6435 regcache_xfree (stop_registers
);
6437 /* NB: The copy goes through to the target picking up the value of
6438 all the registers. */
6439 stop_registers
= regcache_dup (get_current_regcache ());
6442 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6444 /* Pop the empty frame that contains the stack dummy.
6445 This also restores inferior state prior to the call
6446 (struct infcall_suspend_state). */
6447 struct frame_info
*frame
= get_current_frame ();
6449 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6451 /* frame_pop() calls reinit_frame_cache as the last thing it
6452 does which means there's currently no selected frame. We
6453 don't need to re-establish a selected frame if the dummy call
6454 returns normally, that will be done by
6455 restore_infcall_control_state. However, we do have to handle
6456 the case where the dummy call is returning after being
6457 stopped (e.g. the dummy call previously hit a breakpoint).
6458 We can't know which case we have so just always re-establish
6459 a selected frame here. */
6460 select_frame (get_current_frame ());
6464 annotate_stopped ();
6466 /* Suppress the stop observer if we're in the middle of:
6468 - a step n (n > 1), as there still more steps to be done.
6470 - a "finish" command, as the observer will be called in
6471 finish_command_continuation, so it can include the inferior
6472 function's return value.
6474 - calling an inferior function, as we pretend we inferior didn't
6475 run at all. The return value of the call is handled by the
6476 expression evaluator, through call_function_by_hand. */
6478 if (!target_has_execution
6479 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6480 || last
.kind
== TARGET_WAITKIND_EXITED
6481 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6482 || (!(inferior_thread ()->step_multi
6483 && inferior_thread ()->control
.stop_step
)
6484 && !(inferior_thread ()->control
.stop_bpstat
6485 && inferior_thread ()->control
.proceed_to_finish
)
6486 && !inferior_thread ()->control
.in_infcall
))
6488 if (!ptid_equal (inferior_ptid
, null_ptid
))
6489 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6492 observer_notify_normal_stop (NULL
, stop_print_frame
);
6495 if (target_has_execution
)
6497 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6498 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6499 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6500 Delete any breakpoint that is to be deleted at the next stop. */
6501 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6504 /* Try to get rid of automatically added inferiors that are no
6505 longer needed. Keeping those around slows down things linearly.
6506 Note that this never removes the current inferior. */
6511 hook_stop_stub (void *cmd
)
6513 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6518 signal_stop_state (int signo
)
6520 return signal_stop
[signo
];
6524 signal_print_state (int signo
)
6526 return signal_print
[signo
];
6530 signal_pass_state (int signo
)
6532 return signal_program
[signo
];
6536 signal_cache_update (int signo
)
6540 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6541 signal_cache_update (signo
);
6546 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6547 && signal_print
[signo
] == 0
6548 && signal_program
[signo
] == 1
6549 && signal_catch
[signo
] == 0);
6553 signal_stop_update (int signo
, int state
)
6555 int ret
= signal_stop
[signo
];
6557 signal_stop
[signo
] = state
;
6558 signal_cache_update (signo
);
6563 signal_print_update (int signo
, int state
)
6565 int ret
= signal_print
[signo
];
6567 signal_print
[signo
] = state
;
6568 signal_cache_update (signo
);
6573 signal_pass_update (int signo
, int state
)
6575 int ret
= signal_program
[signo
];
6577 signal_program
[signo
] = state
;
6578 signal_cache_update (signo
);
6582 /* Update the global 'signal_catch' from INFO and notify the
6586 signal_catch_update (const unsigned int *info
)
6590 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
6591 signal_catch
[i
] = info
[i
] > 0;
6592 signal_cache_update (-1);
6593 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6597 sig_print_header (void)
6599 printf_filtered (_("Signal Stop\tPrint\tPass "
6600 "to program\tDescription\n"));
6604 sig_print_info (enum gdb_signal oursig
)
6606 const char *name
= gdb_signal_to_name (oursig
);
6607 int name_padding
= 13 - strlen (name
);
6609 if (name_padding
<= 0)
6612 printf_filtered ("%s", name
);
6613 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6614 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6615 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6616 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6617 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6620 /* Specify how various signals in the inferior should be handled. */
6623 handle_command (char *args
, int from_tty
)
6626 int digits
, wordlen
;
6627 int sigfirst
, signum
, siglast
;
6628 enum gdb_signal oursig
;
6631 unsigned char *sigs
;
6632 struct cleanup
*old_chain
;
6636 error_no_arg (_("signal to handle"));
6639 /* Allocate and zero an array of flags for which signals to handle. */
6641 nsigs
= (int) GDB_SIGNAL_LAST
;
6642 sigs
= (unsigned char *) alloca (nsigs
);
6643 memset (sigs
, 0, nsigs
);
6645 /* Break the command line up into args. */
6647 argv
= gdb_buildargv (args
);
6648 old_chain
= make_cleanup_freeargv (argv
);
6650 /* Walk through the args, looking for signal oursigs, signal names, and
6651 actions. Signal numbers and signal names may be interspersed with
6652 actions, with the actions being performed for all signals cumulatively
6653 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6655 while (*argv
!= NULL
)
6657 wordlen
= strlen (*argv
);
6658 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6662 sigfirst
= siglast
= -1;
6664 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6666 /* Apply action to all signals except those used by the
6667 debugger. Silently skip those. */
6670 siglast
= nsigs
- 1;
6672 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6674 SET_SIGS (nsigs
, sigs
, signal_stop
);
6675 SET_SIGS (nsigs
, sigs
, signal_print
);
6677 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6679 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6681 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6683 SET_SIGS (nsigs
, sigs
, signal_print
);
6685 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6687 SET_SIGS (nsigs
, sigs
, signal_program
);
6689 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6691 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6693 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6695 SET_SIGS (nsigs
, sigs
, signal_program
);
6697 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6699 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6700 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6702 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6704 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6706 else if (digits
> 0)
6708 /* It is numeric. The numeric signal refers to our own
6709 internal signal numbering from target.h, not to host/target
6710 signal number. This is a feature; users really should be
6711 using symbolic names anyway, and the common ones like
6712 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6714 sigfirst
= siglast
= (int)
6715 gdb_signal_from_command (atoi (*argv
));
6716 if ((*argv
)[digits
] == '-')
6719 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6721 if (sigfirst
> siglast
)
6723 /* Bet he didn't figure we'd think of this case... */
6731 oursig
= gdb_signal_from_name (*argv
);
6732 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
6734 sigfirst
= siglast
= (int) oursig
;
6738 /* Not a number and not a recognized flag word => complain. */
6739 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6743 /* If any signal numbers or symbol names were found, set flags for
6744 which signals to apply actions to. */
6746 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6748 switch ((enum gdb_signal
) signum
)
6750 case GDB_SIGNAL_TRAP
:
6751 case GDB_SIGNAL_INT
:
6752 if (!allsigs
&& !sigs
[signum
])
6754 if (query (_("%s is used by the debugger.\n\
6755 Are you sure you want to change it? "),
6756 gdb_signal_to_name ((enum gdb_signal
) signum
)))
6762 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6763 gdb_flush (gdb_stdout
);
6768 case GDB_SIGNAL_DEFAULT
:
6769 case GDB_SIGNAL_UNKNOWN
:
6770 /* Make sure that "all" doesn't print these. */
6781 for (signum
= 0; signum
< nsigs
; signum
++)
6784 signal_cache_update (-1);
6785 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6786 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
6790 /* Show the results. */
6791 sig_print_header ();
6792 for (; signum
< nsigs
; signum
++)
6794 sig_print_info (signum
);
6800 do_cleanups (old_chain
);
6803 /* Complete the "handle" command. */
6805 static VEC (char_ptr
) *
6806 handle_completer (struct cmd_list_element
*ignore
,
6807 const char *text
, const char *word
)
6809 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
6810 static const char * const keywords
[] =
6824 vec_signals
= signal_completer (ignore
, text
, word
);
6825 vec_keywords
= complete_on_enum (keywords
, word
, word
);
6827 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
6828 VEC_free (char_ptr
, vec_signals
);
6829 VEC_free (char_ptr
, vec_keywords
);
6834 xdb_handle_command (char *args
, int from_tty
)
6837 struct cleanup
*old_chain
;
6840 error_no_arg (_("xdb command"));
6842 /* Break the command line up into args. */
6844 argv
= gdb_buildargv (args
);
6845 old_chain
= make_cleanup_freeargv (argv
);
6846 if (argv
[1] != (char *) NULL
)
6851 bufLen
= strlen (argv
[0]) + 20;
6852 argBuf
= (char *) xmalloc (bufLen
);
6856 enum gdb_signal oursig
;
6858 oursig
= gdb_signal_from_name (argv
[0]);
6859 memset (argBuf
, 0, bufLen
);
6860 if (strcmp (argv
[1], "Q") == 0)
6861 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6864 if (strcmp (argv
[1], "s") == 0)
6866 if (!signal_stop
[oursig
])
6867 sprintf (argBuf
, "%s %s", argv
[0], "stop");
6869 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
6871 else if (strcmp (argv
[1], "i") == 0)
6873 if (!signal_program
[oursig
])
6874 sprintf (argBuf
, "%s %s", argv
[0], "pass");
6876 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
6878 else if (strcmp (argv
[1], "r") == 0)
6880 if (!signal_print
[oursig
])
6881 sprintf (argBuf
, "%s %s", argv
[0], "print");
6883 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6889 handle_command (argBuf
, from_tty
);
6891 printf_filtered (_("Invalid signal handling flag.\n"));
6896 do_cleanups (old_chain
);
6900 gdb_signal_from_command (int num
)
6902 if (num
>= 1 && num
<= 15)
6903 return (enum gdb_signal
) num
;
6904 error (_("Only signals 1-15 are valid as numeric signals.\n\
6905 Use \"info signals\" for a list of symbolic signals."));
6908 /* Print current contents of the tables set by the handle command.
6909 It is possible we should just be printing signals actually used
6910 by the current target (but for things to work right when switching
6911 targets, all signals should be in the signal tables). */
6914 signals_info (char *signum_exp
, int from_tty
)
6916 enum gdb_signal oursig
;
6918 sig_print_header ();
6922 /* First see if this is a symbol name. */
6923 oursig
= gdb_signal_from_name (signum_exp
);
6924 if (oursig
== GDB_SIGNAL_UNKNOWN
)
6926 /* No, try numeric. */
6928 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
6930 sig_print_info (oursig
);
6934 printf_filtered ("\n");
6935 /* These ugly casts brought to you by the native VAX compiler. */
6936 for (oursig
= GDB_SIGNAL_FIRST
;
6937 (int) oursig
< (int) GDB_SIGNAL_LAST
;
6938 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
6942 if (oursig
!= GDB_SIGNAL_UNKNOWN
6943 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
6944 sig_print_info (oursig
);
6947 printf_filtered (_("\nUse the \"handle\" command "
6948 "to change these tables.\n"));
6951 /* Check if it makes sense to read $_siginfo from the current thread
6952 at this point. If not, throw an error. */
6955 validate_siginfo_access (void)
6957 /* No current inferior, no siginfo. */
6958 if (ptid_equal (inferior_ptid
, null_ptid
))
6959 error (_("No thread selected."));
6961 /* Don't try to read from a dead thread. */
6962 if (is_exited (inferior_ptid
))
6963 error (_("The current thread has terminated"));
6965 /* ... or from a spinning thread. */
6966 if (is_running (inferior_ptid
))
6967 error (_("Selected thread is running."));
6970 /* The $_siginfo convenience variable is a bit special. We don't know
6971 for sure the type of the value until we actually have a chance to
6972 fetch the data. The type can change depending on gdbarch, so it is
6973 also dependent on which thread you have selected.
6975 1. making $_siginfo be an internalvar that creates a new value on
6978 2. making the value of $_siginfo be an lval_computed value. */
6980 /* This function implements the lval_computed support for reading a
6984 siginfo_value_read (struct value
*v
)
6986 LONGEST transferred
;
6988 validate_siginfo_access ();
6991 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
6993 value_contents_all_raw (v
),
6995 TYPE_LENGTH (value_type (v
)));
6997 if (transferred
!= TYPE_LENGTH (value_type (v
)))
6998 error (_("Unable to read siginfo"));
7001 /* This function implements the lval_computed support for writing a
7005 siginfo_value_write (struct value
*v
, struct value
*fromval
)
7007 LONGEST transferred
;
7009 validate_siginfo_access ();
7011 transferred
= target_write (¤t_target
,
7012 TARGET_OBJECT_SIGNAL_INFO
,
7014 value_contents_all_raw (fromval
),
7016 TYPE_LENGTH (value_type (fromval
)));
7018 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
7019 error (_("Unable to write siginfo"));
7022 static const struct lval_funcs siginfo_value_funcs
=
7028 /* Return a new value with the correct type for the siginfo object of
7029 the current thread using architecture GDBARCH. Return a void value
7030 if there's no object available. */
7032 static struct value
*
7033 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
7036 if (target_has_stack
7037 && !ptid_equal (inferior_ptid
, null_ptid
)
7038 && gdbarch_get_siginfo_type_p (gdbarch
))
7040 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7042 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
7045 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
7049 /* infcall_suspend_state contains state about the program itself like its
7050 registers and any signal it received when it last stopped.
7051 This state must be restored regardless of how the inferior function call
7052 ends (either successfully, or after it hits a breakpoint or signal)
7053 if the program is to properly continue where it left off. */
7055 struct infcall_suspend_state
7057 struct thread_suspend_state thread_suspend
;
7058 #if 0 /* Currently unused and empty structures are not valid C. */
7059 struct inferior_suspend_state inferior_suspend
;
7064 struct regcache
*registers
;
7066 /* Format of SIGINFO_DATA or NULL if it is not present. */
7067 struct gdbarch
*siginfo_gdbarch
;
7069 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
7070 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
7071 content would be invalid. */
7072 gdb_byte
*siginfo_data
;
7075 struct infcall_suspend_state
*
7076 save_infcall_suspend_state (void)
7078 struct infcall_suspend_state
*inf_state
;
7079 struct thread_info
*tp
= inferior_thread ();
7081 struct inferior
*inf
= current_inferior ();
7083 struct regcache
*regcache
= get_current_regcache ();
7084 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7085 gdb_byte
*siginfo_data
= NULL
;
7087 if (gdbarch_get_siginfo_type_p (gdbarch
))
7089 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7090 size_t len
= TYPE_LENGTH (type
);
7091 struct cleanup
*back_to
;
7093 siginfo_data
= xmalloc (len
);
7094 back_to
= make_cleanup (xfree
, siginfo_data
);
7096 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
7097 siginfo_data
, 0, len
) == len
)
7098 discard_cleanups (back_to
);
7101 /* Errors ignored. */
7102 do_cleanups (back_to
);
7103 siginfo_data
= NULL
;
7107 inf_state
= XCNEW (struct infcall_suspend_state
);
7111 inf_state
->siginfo_gdbarch
= gdbarch
;
7112 inf_state
->siginfo_data
= siginfo_data
;
7115 inf_state
->thread_suspend
= tp
->suspend
;
7116 #if 0 /* Currently unused and empty structures are not valid C. */
7117 inf_state
->inferior_suspend
= inf
->suspend
;
7120 /* run_inferior_call will not use the signal due to its `proceed' call with
7121 GDB_SIGNAL_0 anyway. */
7122 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7124 inf_state
->stop_pc
= stop_pc
;
7126 inf_state
->registers
= regcache_dup (regcache
);
7131 /* Restore inferior session state to INF_STATE. */
7134 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
7136 struct thread_info
*tp
= inferior_thread ();
7138 struct inferior
*inf
= current_inferior ();
7140 struct regcache
*regcache
= get_current_regcache ();
7141 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7143 tp
->suspend
= inf_state
->thread_suspend
;
7144 #if 0 /* Currently unused and empty structures are not valid C. */
7145 inf
->suspend
= inf_state
->inferior_suspend
;
7148 stop_pc
= inf_state
->stop_pc
;
7150 if (inf_state
->siginfo_gdbarch
== gdbarch
)
7152 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7154 /* Errors ignored. */
7155 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
7156 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
7159 /* The inferior can be gone if the user types "print exit(0)"
7160 (and perhaps other times). */
7161 if (target_has_execution
)
7162 /* NB: The register write goes through to the target. */
7163 regcache_cpy (regcache
, inf_state
->registers
);
7165 discard_infcall_suspend_state (inf_state
);
7169 do_restore_infcall_suspend_state_cleanup (void *state
)
7171 restore_infcall_suspend_state (state
);
7175 make_cleanup_restore_infcall_suspend_state
7176 (struct infcall_suspend_state
*inf_state
)
7178 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
7182 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
7184 regcache_xfree (inf_state
->registers
);
7185 xfree (inf_state
->siginfo_data
);
7190 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
7192 return inf_state
->registers
;
7195 /* infcall_control_state contains state regarding gdb's control of the
7196 inferior itself like stepping control. It also contains session state like
7197 the user's currently selected frame. */
7199 struct infcall_control_state
7201 struct thread_control_state thread_control
;
7202 struct inferior_control_state inferior_control
;
7205 enum stop_stack_kind stop_stack_dummy
;
7206 int stopped_by_random_signal
;
7207 int stop_after_trap
;
7209 /* ID if the selected frame when the inferior function call was made. */
7210 struct frame_id selected_frame_id
;
7213 /* Save all of the information associated with the inferior<==>gdb
7216 struct infcall_control_state
*
7217 save_infcall_control_state (void)
7219 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
7220 struct thread_info
*tp
= inferior_thread ();
7221 struct inferior
*inf
= current_inferior ();
7223 inf_status
->thread_control
= tp
->control
;
7224 inf_status
->inferior_control
= inf
->control
;
7226 tp
->control
.step_resume_breakpoint
= NULL
;
7227 tp
->control
.exception_resume_breakpoint
= NULL
;
7229 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
7230 chain. If caller's caller is walking the chain, they'll be happier if we
7231 hand them back the original chain when restore_infcall_control_state is
7233 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
7236 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
7237 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
7238 inf_status
->stop_after_trap
= stop_after_trap
;
7240 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
7246 restore_selected_frame (void *args
)
7248 struct frame_id
*fid
= (struct frame_id
*) args
;
7249 struct frame_info
*frame
;
7251 frame
= frame_find_by_id (*fid
);
7253 /* If inf_status->selected_frame_id is NULL, there was no previously
7257 warning (_("Unable to restore previously selected frame."));
7261 select_frame (frame
);
7266 /* Restore inferior session state to INF_STATUS. */
7269 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
7271 struct thread_info
*tp
= inferior_thread ();
7272 struct inferior
*inf
= current_inferior ();
7274 if (tp
->control
.step_resume_breakpoint
)
7275 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
7277 if (tp
->control
.exception_resume_breakpoint
)
7278 tp
->control
.exception_resume_breakpoint
->disposition
7279 = disp_del_at_next_stop
;
7281 /* Handle the bpstat_copy of the chain. */
7282 bpstat_clear (&tp
->control
.stop_bpstat
);
7284 tp
->control
= inf_status
->thread_control
;
7285 inf
->control
= inf_status
->inferior_control
;
7288 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
7289 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
7290 stop_after_trap
= inf_status
->stop_after_trap
;
7292 if (target_has_stack
)
7294 /* The point of catch_errors is that if the stack is clobbered,
7295 walking the stack might encounter a garbage pointer and
7296 error() trying to dereference it. */
7298 (restore_selected_frame
, &inf_status
->selected_frame_id
,
7299 "Unable to restore previously selected frame:\n",
7300 RETURN_MASK_ERROR
) == 0)
7301 /* Error in restoring the selected frame. Select the innermost
7303 select_frame (get_current_frame ());
7310 do_restore_infcall_control_state_cleanup (void *sts
)
7312 restore_infcall_control_state (sts
);
7316 make_cleanup_restore_infcall_control_state
7317 (struct infcall_control_state
*inf_status
)
7319 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
7323 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
7325 if (inf_status
->thread_control
.step_resume_breakpoint
)
7326 inf_status
->thread_control
.step_resume_breakpoint
->disposition
7327 = disp_del_at_next_stop
;
7329 if (inf_status
->thread_control
.exception_resume_breakpoint
)
7330 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
7331 = disp_del_at_next_stop
;
7333 /* See save_infcall_control_state for info on stop_bpstat. */
7334 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
7339 /* restore_inferior_ptid() will be used by the cleanup machinery
7340 to restore the inferior_ptid value saved in a call to
7341 save_inferior_ptid(). */
7344 restore_inferior_ptid (void *arg
)
7346 ptid_t
*saved_ptid_ptr
= arg
;
7348 inferior_ptid
= *saved_ptid_ptr
;
7352 /* Save the value of inferior_ptid so that it may be restored by a
7353 later call to do_cleanups(). Returns the struct cleanup pointer
7354 needed for later doing the cleanup. */
7357 save_inferior_ptid (void)
7359 ptid_t
*saved_ptid_ptr
;
7361 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
7362 *saved_ptid_ptr
= inferior_ptid
;
7363 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
7369 clear_exit_convenience_vars (void)
7371 clear_internalvar (lookup_internalvar ("_exitsignal"));
7372 clear_internalvar (lookup_internalvar ("_exitcode"));
7376 /* User interface for reverse debugging:
7377 Set exec-direction / show exec-direction commands
7378 (returns error unless target implements to_set_exec_direction method). */
7380 int execution_direction
= EXEC_FORWARD
;
7381 static const char exec_forward
[] = "forward";
7382 static const char exec_reverse
[] = "reverse";
7383 static const char *exec_direction
= exec_forward
;
7384 static const char *const exec_direction_names
[] = {
7391 set_exec_direction_func (char *args
, int from_tty
,
7392 struct cmd_list_element
*cmd
)
7394 if (target_can_execute_reverse
)
7396 if (!strcmp (exec_direction
, exec_forward
))
7397 execution_direction
= EXEC_FORWARD
;
7398 else if (!strcmp (exec_direction
, exec_reverse
))
7399 execution_direction
= EXEC_REVERSE
;
7403 exec_direction
= exec_forward
;
7404 error (_("Target does not support this operation."));
7409 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7410 struct cmd_list_element
*cmd
, const char *value
)
7412 switch (execution_direction
) {
7414 fprintf_filtered (out
, _("Forward.\n"));
7417 fprintf_filtered (out
, _("Reverse.\n"));
7420 internal_error (__FILE__
, __LINE__
,
7421 _("bogus execution_direction value: %d"),
7422 (int) execution_direction
);
7427 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7428 struct cmd_list_element
*c
, const char *value
)
7430 fprintf_filtered (file
, _("Resuming the execution of threads "
7431 "of all processes is %s.\n"), value
);
7434 /* Implementation of `siginfo' variable. */
7436 static const struct internalvar_funcs siginfo_funcs
=
7444 _initialize_infrun (void)
7448 struct cmd_list_element
*c
;
7450 add_info ("signals", signals_info
, _("\
7451 What debugger does when program gets various signals.\n\
7452 Specify a signal as argument to print info on that signal only."));
7453 add_info_alias ("handle", "signals", 0);
7455 c
= add_com ("handle", class_run
, handle_command
, _("\
7456 Specify how to handle signals.\n\
7457 Usage: handle SIGNAL [ACTIONS]\n\
7458 Args are signals and actions to apply to those signals.\n\
7459 If no actions are specified, the current settings for the specified signals\n\
7460 will be displayed instead.\n\
7462 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7463 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7464 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7465 The special arg \"all\" is recognized to mean all signals except those\n\
7466 used by the debugger, typically SIGTRAP and SIGINT.\n\
7468 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7469 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7470 Stop means reenter debugger if this signal happens (implies print).\n\
7471 Print means print a message if this signal happens.\n\
7472 Pass means let program see this signal; otherwise program doesn't know.\n\
7473 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7474 Pass and Stop may be combined.\n\
7476 Multiple signals may be specified. Signal numbers and signal names\n\
7477 may be interspersed with actions, with the actions being performed for\n\
7478 all signals cumulatively specified."));
7479 set_cmd_completer (c
, handle_completer
);
7483 add_com ("lz", class_info
, signals_info
, _("\
7484 What debugger does when program gets various signals.\n\
7485 Specify a signal as argument to print info on that signal only."));
7486 add_com ("z", class_run
, xdb_handle_command
, _("\
7487 Specify how to handle a signal.\n\
7488 Args are signals and actions to apply to those signals.\n\
7489 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7490 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7491 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7492 The special arg \"all\" is recognized to mean all signals except those\n\
7493 used by the debugger, typically SIGTRAP and SIGINT.\n\
7494 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7495 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7496 nopass), \"Q\" (noprint)\n\
7497 Stop means reenter debugger if this signal happens (implies print).\n\
7498 Print means print a message if this signal happens.\n\
7499 Pass means let program see this signal; otherwise program doesn't know.\n\
7500 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7501 Pass and Stop may be combined."));
7505 stop_command
= add_cmd ("stop", class_obscure
,
7506 not_just_help_class_command
, _("\
7507 There is no `stop' command, but you can set a hook on `stop'.\n\
7508 This allows you to set a list of commands to be run each time execution\n\
7509 of the program stops."), &cmdlist
);
7511 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7512 Set inferior debugging."), _("\
7513 Show inferior debugging."), _("\
7514 When non-zero, inferior specific debugging is enabled."),
7517 &setdebuglist
, &showdebuglist
);
7519 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7520 &debug_displaced
, _("\
7521 Set displaced stepping debugging."), _("\
7522 Show displaced stepping debugging."), _("\
7523 When non-zero, displaced stepping specific debugging is enabled."),
7525 show_debug_displaced
,
7526 &setdebuglist
, &showdebuglist
);
7528 add_setshow_boolean_cmd ("non-stop", no_class
,
7530 Set whether gdb controls the inferior in non-stop mode."), _("\
7531 Show whether gdb controls the inferior in non-stop mode."), _("\
7532 When debugging a multi-threaded program and this setting is\n\
7533 off (the default, also called all-stop mode), when one thread stops\n\
7534 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7535 all other threads in the program while you interact with the thread of\n\
7536 interest. When you continue or step a thread, you can allow the other\n\
7537 threads to run, or have them remain stopped, but while you inspect any\n\
7538 thread's state, all threads stop.\n\
7540 In non-stop mode, when one thread stops, other threads can continue\n\
7541 to run freely. You'll be able to step each thread independently,\n\
7542 leave it stopped or free to run as needed."),
7548 numsigs
= (int) GDB_SIGNAL_LAST
;
7549 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7550 signal_print
= (unsigned char *)
7551 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7552 signal_program
= (unsigned char *)
7553 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7554 signal_catch
= (unsigned char *)
7555 xmalloc (sizeof (signal_catch
[0]) * numsigs
);
7556 signal_pass
= (unsigned char *)
7557 xmalloc (sizeof (signal_pass
[0]) * numsigs
);
7558 for (i
= 0; i
< numsigs
; i
++)
7561 signal_print
[i
] = 1;
7562 signal_program
[i
] = 1;
7563 signal_catch
[i
] = 0;
7566 /* Signals caused by debugger's own actions
7567 should not be given to the program afterwards. */
7568 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7569 signal_program
[GDB_SIGNAL_INT
] = 0;
7571 /* Signals that are not errors should not normally enter the debugger. */
7572 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7573 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7574 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7575 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7576 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7577 signal_print
[GDB_SIGNAL_PROF
] = 0;
7578 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7579 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7580 signal_stop
[GDB_SIGNAL_IO
] = 0;
7581 signal_print
[GDB_SIGNAL_IO
] = 0;
7582 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7583 signal_print
[GDB_SIGNAL_POLL
] = 0;
7584 signal_stop
[GDB_SIGNAL_URG
] = 0;
7585 signal_print
[GDB_SIGNAL_URG
] = 0;
7586 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7587 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7588 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7589 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7591 /* These signals are used internally by user-level thread
7592 implementations. (See signal(5) on Solaris.) Like the above
7593 signals, a healthy program receives and handles them as part of
7594 its normal operation. */
7595 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7596 signal_print
[GDB_SIGNAL_LWP
] = 0;
7597 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7598 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7599 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7600 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7602 /* Update cached state. */
7603 signal_cache_update (-1);
7605 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7606 &stop_on_solib_events
, _("\
7607 Set stopping for shared library events."), _("\
7608 Show stopping for shared library events."), _("\
7609 If nonzero, gdb will give control to the user when the dynamic linker\n\
7610 notifies gdb of shared library events. The most common event of interest\n\
7611 to the user would be loading/unloading of a new library."),
7612 set_stop_on_solib_events
,
7613 show_stop_on_solib_events
,
7614 &setlist
, &showlist
);
7616 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7617 follow_fork_mode_kind_names
,
7618 &follow_fork_mode_string
, _("\
7619 Set debugger response to a program call of fork or vfork."), _("\
7620 Show debugger response to a program call of fork or vfork."), _("\
7621 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7622 parent - the original process is debugged after a fork\n\
7623 child - the new process is debugged after a fork\n\
7624 The unfollowed process will continue to run.\n\
7625 By default, the debugger will follow the parent process."),
7627 show_follow_fork_mode_string
,
7628 &setlist
, &showlist
);
7630 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7631 follow_exec_mode_names
,
7632 &follow_exec_mode_string
, _("\
7633 Set debugger response to a program call of exec."), _("\
7634 Show debugger response to a program call of exec."), _("\
7635 An exec call replaces the program image of a process.\n\
7637 follow-exec-mode can be:\n\
7639 new - the debugger creates a new inferior and rebinds the process\n\
7640 to this new inferior. The program the process was running before\n\
7641 the exec call can be restarted afterwards by restarting the original\n\
7644 same - the debugger keeps the process bound to the same inferior.\n\
7645 The new executable image replaces the previous executable loaded in\n\
7646 the inferior. Restarting the inferior after the exec call restarts\n\
7647 the executable the process was running after the exec call.\n\
7649 By default, the debugger will use the same inferior."),
7651 show_follow_exec_mode_string
,
7652 &setlist
, &showlist
);
7654 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7655 scheduler_enums
, &scheduler_mode
, _("\
7656 Set mode for locking scheduler during execution."), _("\
7657 Show mode for locking scheduler during execution."), _("\
7658 off == no locking (threads may preempt at any time)\n\
7659 on == full locking (no thread except the current thread may run)\n\
7660 step == scheduler locked during every single-step operation.\n\
7661 In this mode, no other thread may run during a step command.\n\
7662 Other threads may run while stepping over a function call ('next')."),
7663 set_schedlock_func
, /* traps on target vector */
7664 show_scheduler_mode
,
7665 &setlist
, &showlist
);
7667 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7668 Set mode for resuming threads of all processes."), _("\
7669 Show mode for resuming threads of all processes."), _("\
7670 When on, execution commands (such as 'continue' or 'next') resume all\n\
7671 threads of all processes. When off (which is the default), execution\n\
7672 commands only resume the threads of the current process. The set of\n\
7673 threads that are resumed is further refined by the scheduler-locking\n\
7674 mode (see help set scheduler-locking)."),
7676 show_schedule_multiple
,
7677 &setlist
, &showlist
);
7679 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7680 Set mode of the step operation."), _("\
7681 Show mode of the step operation."), _("\
7682 When set, doing a step over a function without debug line information\n\
7683 will stop at the first instruction of that function. Otherwise, the\n\
7684 function is skipped and the step command stops at a different source line."),
7686 show_step_stop_if_no_debug
,
7687 &setlist
, &showlist
);
7689 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
7690 &can_use_displaced_stepping
, _("\
7691 Set debugger's willingness to use displaced stepping."), _("\
7692 Show debugger's willingness to use displaced stepping."), _("\
7693 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7694 supported by the target architecture. If off, gdb will not use displaced\n\
7695 stepping to step over breakpoints, even if such is supported by the target\n\
7696 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7697 if the target architecture supports it and non-stop mode is active, but will not\n\
7698 use it in all-stop mode (see help set non-stop)."),
7700 show_can_use_displaced_stepping
,
7701 &setlist
, &showlist
);
7703 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7704 &exec_direction
, _("Set direction of execution.\n\
7705 Options are 'forward' or 'reverse'."),
7706 _("Show direction of execution (forward/reverse)."),
7707 _("Tells gdb whether to execute forward or backward."),
7708 set_exec_direction_func
, show_exec_direction_func
,
7709 &setlist
, &showlist
);
7711 /* Set/show detach-on-fork: user-settable mode. */
7713 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7714 Set whether gdb will detach the child of a fork."), _("\
7715 Show whether gdb will detach the child of a fork."), _("\
7716 Tells gdb whether to detach the child of a fork."),
7717 NULL
, NULL
, &setlist
, &showlist
);
7719 /* Set/show disable address space randomization mode. */
7721 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7722 &disable_randomization
, _("\
7723 Set disabling of debuggee's virtual address space randomization."), _("\
7724 Show disabling of debuggee's virtual address space randomization."), _("\
7725 When this mode is on (which is the default), randomization of the virtual\n\
7726 address space is disabled. Standalone programs run with the randomization\n\
7727 enabled by default on some platforms."),
7728 &set_disable_randomization
,
7729 &show_disable_randomization
,
7730 &setlist
, &showlist
);
7732 /* ptid initializations */
7733 inferior_ptid
= null_ptid
;
7734 target_last_wait_ptid
= minus_one_ptid
;
7736 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7737 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7738 observer_attach_thread_exit (infrun_thread_thread_exit
);
7739 observer_attach_inferior_exit (infrun_inferior_exit
);
7741 /* Explicitly create without lookup, since that tries to create a
7742 value with a void typed value, and when we get here, gdbarch
7743 isn't initialized yet. At this point, we're quite sure there
7744 isn't another convenience variable of the same name. */
7745 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7747 add_setshow_boolean_cmd ("observer", no_class
,
7748 &observer_mode_1
, _("\
7749 Set whether gdb controls the inferior in observer mode."), _("\
7750 Show whether gdb controls the inferior in observer mode."), _("\
7751 In observer mode, GDB can get data from the inferior, but not\n\
7752 affect its execution. Registers and memory may not be changed,\n\
7753 breakpoints may not be set, and the program cannot be interrupted\n\