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 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2081 /* If we have a breakpoint to step over, make sure to do a single
2082 step only. Same if we have software watchpoints. */
2083 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2084 tp
->control
.may_range_step
= 0;
2086 /* If enabled, step over breakpoints by executing a copy of the
2087 instruction at a different address.
2089 We can't use displaced stepping when we have a signal to deliver;
2090 the comments for displaced_step_prepare explain why. The
2091 comments in the handle_inferior event for dealing with 'random
2092 signals' explain what we do instead.
2094 We can't use displaced stepping when we are waiting for vfork_done
2095 event, displaced stepping breaks the vfork child similarly as single
2096 step software breakpoint. */
2097 if (use_displaced_stepping (gdbarch
)
2098 && tp
->control
.trap_expected
2099 && sig
== GDB_SIGNAL_0
2100 && !current_inferior ()->waiting_for_vfork_done
)
2102 struct displaced_step_inferior_state
*displaced
;
2104 if (!displaced_step_prepare (inferior_ptid
))
2106 /* Got placed in displaced stepping queue. Will be resumed
2107 later when all the currently queued displaced stepping
2108 requests finish. The thread is not executing at this
2109 point, and the call to set_executing will be made later.
2110 But we need to call set_running here, since from the
2111 user/frontend's point of view, threads were set running.
2112 Unless we're calling an inferior function, as in that
2113 case we pretend the inferior doesn't run at all. */
2114 if (!tp
->control
.in_infcall
)
2115 set_running (user_visible_resume_ptid (entry_step
), 1);
2116 discard_cleanups (old_cleanups
);
2120 /* Update pc to reflect the new address from which we will execute
2121 instructions due to displaced stepping. */
2122 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2124 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2125 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2126 displaced
->step_closure
);
2129 /* Do we need to do it the hard way, w/temp breakpoints? */
2131 step
= maybe_software_singlestep (gdbarch
, pc
);
2133 /* Currently, our software single-step implementation leads to different
2134 results than hardware single-stepping in one situation: when stepping
2135 into delivering a signal which has an associated signal handler,
2136 hardware single-step will stop at the first instruction of the handler,
2137 while software single-step will simply skip execution of the handler.
2139 For now, this difference in behavior is accepted since there is no
2140 easy way to actually implement single-stepping into a signal handler
2141 without kernel support.
2143 However, there is one scenario where this difference leads to follow-on
2144 problems: if we're stepping off a breakpoint by removing all breakpoints
2145 and then single-stepping. In this case, the software single-step
2146 behavior means that even if there is a *breakpoint* in the signal
2147 handler, GDB still would not stop.
2149 Fortunately, we can at least fix this particular issue. We detect
2150 here the case where we are about to deliver a signal while software
2151 single-stepping with breakpoints removed. In this situation, we
2152 revert the decisions to remove all breakpoints and insert single-
2153 step breakpoints, and instead we install a step-resume breakpoint
2154 at the current address, deliver the signal without stepping, and
2155 once we arrive back at the step-resume breakpoint, actually step
2156 over the breakpoint we originally wanted to step over. */
2157 if (thread_has_single_step_breakpoints_set (tp
)
2158 && sig
!= GDB_SIGNAL_0
2159 && step_over_info_valid_p ())
2161 /* If we have nested signals or a pending signal is delivered
2162 immediately after a handler returns, might might already have
2163 a step-resume breakpoint set on the earlier handler. We cannot
2164 set another step-resume breakpoint; just continue on until the
2165 original breakpoint is hit. */
2166 if (tp
->control
.step_resume_breakpoint
== NULL
)
2168 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2169 tp
->step_after_step_resume_breakpoint
= 1;
2172 delete_single_step_breakpoints (tp
);
2174 clear_step_over_info ();
2175 tp
->control
.trap_expected
= 0;
2177 insert_breakpoints ();
2180 /* If STEP is set, it's a request to use hardware stepping
2181 facilities. But in that case, we should never
2182 use singlestep breakpoint. */
2183 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2185 /* Decide the set of threads to ask the target to resume. Start
2186 by assuming everything will be resumed, than narrow the set
2187 by applying increasingly restricting conditions. */
2188 resume_ptid
= user_visible_resume_ptid (entry_step
);
2190 /* Even if RESUME_PTID is a wildcard, and we end up resuming less
2191 (e.g., we might need to step over a breakpoint), from the
2192 user/frontend's point of view, all threads in RESUME_PTID are now
2193 running. Unless we're calling an inferior function, as in that
2194 case pretend we inferior doesn't run at all. */
2195 if (!tp
->control
.in_infcall
)
2196 set_running (resume_ptid
, 1);
2198 /* Maybe resume a single thread after all. */
2199 if ((step
|| thread_has_single_step_breakpoints_set (tp
))
2200 && tp
->control
.trap_expected
)
2202 /* We're allowing a thread to run past a breakpoint it has
2203 hit, by single-stepping the thread with the breakpoint
2204 removed. In which case, we need to single-step only this
2205 thread, and keep others stopped, as they can miss this
2206 breakpoint if allowed to run. */
2207 resume_ptid
= inferior_ptid
;
2210 if (execution_direction
!= EXEC_REVERSE
2211 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2213 /* The only case we currently need to step a breakpoint
2214 instruction is when we have a signal to deliver. See
2215 handle_signal_stop where we handle random signals that could
2216 take out us out of the stepping range. Normally, in that
2217 case we end up continuing (instead of stepping) over the
2218 signal handler with a breakpoint at PC, but there are cases
2219 where we should _always_ single-step, even if we have a
2220 step-resume breakpoint, like when a software watchpoint is
2221 set. Assuming single-stepping and delivering a signal at the
2222 same time would takes us to the signal handler, then we could
2223 have removed the breakpoint at PC to step over it. However,
2224 some hardware step targets (like e.g., Mac OS) can't step
2225 into signal handlers, and for those, we need to leave the
2226 breakpoint at PC inserted, as otherwise if the handler
2227 recurses and executes PC again, it'll miss the breakpoint.
2228 So we leave the breakpoint inserted anyway, but we need to
2229 record that we tried to step a breakpoint instruction, so
2230 that adjust_pc_after_break doesn't end up confused. */
2231 gdb_assert (sig
!= GDB_SIGNAL_0
);
2233 tp
->stepped_breakpoint
= 1;
2235 /* Most targets can step a breakpoint instruction, thus
2236 executing it normally. But if this one cannot, just
2237 continue and we will hit it anyway. */
2238 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2243 && use_displaced_stepping (gdbarch
)
2244 && tp
->control
.trap_expected
)
2246 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
2247 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2248 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2251 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2252 paddress (resume_gdbarch
, actual_pc
));
2253 read_memory (actual_pc
, buf
, sizeof (buf
));
2254 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2257 if (tp
->control
.may_range_step
)
2259 /* If we're resuming a thread with the PC out of the step
2260 range, then we're doing some nested/finer run control
2261 operation, like stepping the thread out of the dynamic
2262 linker or the displaced stepping scratch pad. We
2263 shouldn't have allowed a range step then. */
2264 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2267 /* Install inferior's terminal modes. */
2268 target_terminal_inferior ();
2270 /* Avoid confusing the next resume, if the next stop/resume
2271 happens to apply to another thread. */
2272 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2274 /* Advise target which signals may be handled silently. If we have
2275 removed breakpoints because we are stepping over one (in any
2276 thread), we need to receive all signals to avoid accidentally
2277 skipping a breakpoint during execution of a signal handler. */
2278 if (step_over_info_valid_p ())
2279 target_pass_signals (0, NULL
);
2281 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2283 target_resume (resume_ptid
, step
, sig
);
2285 discard_cleanups (old_cleanups
);
2290 /* Clear out all variables saying what to do when inferior is continued.
2291 First do this, then set the ones you want, then call `proceed'. */
2294 clear_proceed_status_thread (struct thread_info
*tp
)
2297 fprintf_unfiltered (gdb_stdlog
,
2298 "infrun: clear_proceed_status_thread (%s)\n",
2299 target_pid_to_str (tp
->ptid
));
2301 /* If this signal should not be seen by program, give it zero.
2302 Used for debugging signals. */
2303 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2304 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2306 tp
->control
.trap_expected
= 0;
2307 tp
->control
.step_range_start
= 0;
2308 tp
->control
.step_range_end
= 0;
2309 tp
->control
.may_range_step
= 0;
2310 tp
->control
.step_frame_id
= null_frame_id
;
2311 tp
->control
.step_stack_frame_id
= null_frame_id
;
2312 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2313 tp
->stop_requested
= 0;
2315 tp
->control
.stop_step
= 0;
2317 tp
->control
.proceed_to_finish
= 0;
2319 tp
->control
.command_interp
= NULL
;
2321 /* Discard any remaining commands or status from previous stop. */
2322 bpstat_clear (&tp
->control
.stop_bpstat
);
2326 clear_proceed_status (int step
)
2330 struct thread_info
*tp
;
2333 resume_ptid
= user_visible_resume_ptid (step
);
2335 /* In all-stop mode, delete the per-thread status of all threads
2336 we're about to resume, implicitly and explicitly. */
2337 ALL_NON_EXITED_THREADS (tp
)
2339 if (!ptid_match (tp
->ptid
, resume_ptid
))
2341 clear_proceed_status_thread (tp
);
2345 if (!ptid_equal (inferior_ptid
, null_ptid
))
2347 struct inferior
*inferior
;
2351 /* If in non-stop mode, only delete the per-thread status of
2352 the current thread. */
2353 clear_proceed_status_thread (inferior_thread ());
2356 inferior
= current_inferior ();
2357 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2360 stop_after_trap
= 0;
2362 clear_step_over_info ();
2364 observer_notify_about_to_proceed ();
2368 regcache_xfree (stop_registers
);
2369 stop_registers
= NULL
;
2373 /* Returns true if TP is still stopped at a breakpoint that needs
2374 stepping-over in order to make progress. If the breakpoint is gone
2375 meanwhile, we can skip the whole step-over dance. */
2378 thread_still_needs_step_over (struct thread_info
*tp
)
2380 if (tp
->stepping_over_breakpoint
)
2382 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2384 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2385 regcache_read_pc (regcache
)))
2388 tp
->stepping_over_breakpoint
= 0;
2394 /* Returns true if scheduler locking applies. STEP indicates whether
2395 we're about to do a step/next-like command to a thread. */
2398 schedlock_applies (int step
)
2400 return (scheduler_mode
== schedlock_on
2401 || (scheduler_mode
== schedlock_step
2405 /* Look a thread other than EXCEPT that has previously reported a
2406 breakpoint event, and thus needs a step-over in order to make
2407 progress. Returns NULL is none is found. STEP indicates whether
2408 we're about to step the current thread, in order to decide whether
2409 "set scheduler-locking step" applies. */
2411 static struct thread_info
*
2412 find_thread_needs_step_over (int step
, struct thread_info
*except
)
2414 struct thread_info
*tp
, *current
;
2416 /* With non-stop mode on, threads are always handled individually. */
2417 gdb_assert (! non_stop
);
2419 current
= inferior_thread ();
2421 /* If scheduler locking applies, we can avoid iterating over all
2423 if (schedlock_applies (step
))
2425 if (except
!= current
2426 && thread_still_needs_step_over (current
))
2432 ALL_NON_EXITED_THREADS (tp
)
2434 /* Ignore the EXCEPT thread. */
2437 /* Ignore threads of processes we're not resuming. */
2439 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (inferior_ptid
))
2442 if (thread_still_needs_step_over (tp
))
2449 /* Basic routine for continuing the program in various fashions.
2451 ADDR is the address to resume at, or -1 for resume where stopped.
2452 SIGGNAL is the signal to give it, or 0 for none,
2453 or -1 for act according to how it stopped.
2454 STEP is nonzero if should trap after one instruction.
2455 -1 means return after that and print nothing.
2456 You should probably set various step_... variables
2457 before calling here, if you are stepping.
2459 You should call clear_proceed_status before calling proceed. */
2462 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
, int step
)
2464 struct regcache
*regcache
;
2465 struct gdbarch
*gdbarch
;
2466 struct thread_info
*tp
;
2468 struct address_space
*aspace
;
2470 /* If we're stopped at a fork/vfork, follow the branch set by the
2471 "set follow-fork-mode" command; otherwise, we'll just proceed
2472 resuming the current thread. */
2473 if (!follow_fork ())
2475 /* The target for some reason decided not to resume. */
2477 if (target_can_async_p ())
2478 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2482 /* We'll update this if & when we switch to a new thread. */
2483 previous_inferior_ptid
= inferior_ptid
;
2485 regcache
= get_current_regcache ();
2486 gdbarch
= get_regcache_arch (regcache
);
2487 aspace
= get_regcache_aspace (regcache
);
2488 pc
= regcache_read_pc (regcache
);
2489 tp
= inferior_thread ();
2492 step_start_function
= find_pc_function (pc
);
2494 stop_after_trap
= 1;
2496 /* Fill in with reasonable starting values. */
2497 init_thread_stepping_state (tp
);
2499 if (addr
== (CORE_ADDR
) -1)
2501 if (pc
== stop_pc
&& breakpoint_here_p (aspace
, pc
)
2502 && execution_direction
!= EXEC_REVERSE
)
2503 /* There is a breakpoint at the address we will resume at,
2504 step one instruction before inserting breakpoints so that
2505 we do not stop right away (and report a second hit at this
2508 Note, we don't do this in reverse, because we won't
2509 actually be executing the breakpoint insn anyway.
2510 We'll be (un-)executing the previous instruction. */
2511 tp
->stepping_over_breakpoint
= 1;
2512 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2513 && gdbarch_single_step_through_delay (gdbarch
,
2514 get_current_frame ()))
2515 /* We stepped onto an instruction that needs to be stepped
2516 again before re-inserting the breakpoint, do so. */
2517 tp
->stepping_over_breakpoint
= 1;
2521 regcache_write_pc (regcache
, addr
);
2524 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2525 tp
->suspend
.stop_signal
= siggnal
;
2527 /* Record the interpreter that issued the execution command that
2528 caused this thread to resume. If the top level interpreter is
2529 MI/async, and the execution command was a CLI command
2530 (next/step/etc.), we'll want to print stop event output to the MI
2531 console channel (the stepped-to line, etc.), as if the user
2532 entered the execution command on a real GDB console. */
2533 inferior_thread ()->control
.command_interp
= command_interp ();
2536 fprintf_unfiltered (gdb_stdlog
,
2537 "infrun: proceed (addr=%s, signal=%s, step=%d)\n",
2538 paddress (gdbarch
, addr
),
2539 gdb_signal_to_symbol_string (siggnal
), step
);
2542 /* In non-stop, each thread is handled individually. The context
2543 must already be set to the right thread here. */
2547 struct thread_info
*step_over
;
2549 /* In a multi-threaded task we may select another thread and
2550 then continue or step.
2552 But if the old thread was stopped at a breakpoint, it will
2553 immediately cause another breakpoint stop without any
2554 execution (i.e. it will report a breakpoint hit incorrectly).
2555 So we must step over it first.
2557 Look for a thread other than the current (TP) that reported a
2558 breakpoint hit and hasn't been resumed yet since. */
2559 step_over
= find_thread_needs_step_over (step
, tp
);
2560 if (step_over
!= NULL
)
2563 fprintf_unfiltered (gdb_stdlog
,
2564 "infrun: need to step-over [%s] first\n",
2565 target_pid_to_str (step_over
->ptid
));
2567 /* Store the prev_pc for the stepping thread too, needed by
2568 switch_back_to_stepping thread. */
2569 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2570 switch_to_thread (step_over
->ptid
);
2575 /* If we need to step over a breakpoint, and we're not using
2576 displaced stepping to do so, insert all breakpoints (watchpoints,
2577 etc.) but the one we're stepping over, step one instruction, and
2578 then re-insert the breakpoint when that step is finished. */
2579 if (tp
->stepping_over_breakpoint
&& !use_displaced_stepping (gdbarch
))
2581 struct regcache
*regcache
= get_current_regcache ();
2583 set_step_over_info (get_regcache_aspace (regcache
),
2584 regcache_read_pc (regcache
), 0);
2587 clear_step_over_info ();
2589 insert_breakpoints ();
2591 tp
->control
.trap_expected
= tp
->stepping_over_breakpoint
;
2593 annotate_starting ();
2595 /* Make sure that output from GDB appears before output from the
2597 gdb_flush (gdb_stdout
);
2599 /* Refresh prev_pc value just prior to resuming. This used to be
2600 done in stop_waiting, however, setting prev_pc there did not handle
2601 scenarios such as inferior function calls or returning from
2602 a function via the return command. In those cases, the prev_pc
2603 value was not set properly for subsequent commands. The prev_pc value
2604 is used to initialize the starting line number in the ecs. With an
2605 invalid value, the gdb next command ends up stopping at the position
2606 represented by the next line table entry past our start position.
2607 On platforms that generate one line table entry per line, this
2608 is not a problem. However, on the ia64, the compiler generates
2609 extraneous line table entries that do not increase the line number.
2610 When we issue the gdb next command on the ia64 after an inferior call
2611 or a return command, we often end up a few instructions forward, still
2612 within the original line we started.
2614 An attempt was made to refresh the prev_pc at the same time the
2615 execution_control_state is initialized (for instance, just before
2616 waiting for an inferior event). But this approach did not work
2617 because of platforms that use ptrace, where the pc register cannot
2618 be read unless the inferior is stopped. At that point, we are not
2619 guaranteed the inferior is stopped and so the regcache_read_pc() call
2620 can fail. Setting the prev_pc value here ensures the value is updated
2621 correctly when the inferior is stopped. */
2622 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2624 /* Resume inferior. */
2625 resume (tp
->control
.trap_expected
|| step
|| bpstat_should_step (),
2626 tp
->suspend
.stop_signal
);
2628 /* Wait for it to stop (if not standalone)
2629 and in any case decode why it stopped, and act accordingly. */
2630 /* Do this only if we are not using the event loop, or if the target
2631 does not support asynchronous execution. */
2632 if (!target_can_async_p ())
2634 wait_for_inferior ();
2640 /* Start remote-debugging of a machine over a serial link. */
2643 start_remote (int from_tty
)
2645 struct inferior
*inferior
;
2647 inferior
= current_inferior ();
2648 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
2650 /* Always go on waiting for the target, regardless of the mode. */
2651 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2652 indicate to wait_for_inferior that a target should timeout if
2653 nothing is returned (instead of just blocking). Because of this,
2654 targets expecting an immediate response need to, internally, set
2655 things up so that the target_wait() is forced to eventually
2657 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2658 differentiate to its caller what the state of the target is after
2659 the initial open has been performed. Here we're assuming that
2660 the target has stopped. It should be possible to eventually have
2661 target_open() return to the caller an indication that the target
2662 is currently running and GDB state should be set to the same as
2663 for an async run. */
2664 wait_for_inferior ();
2666 /* Now that the inferior has stopped, do any bookkeeping like
2667 loading shared libraries. We want to do this before normal_stop,
2668 so that the displayed frame is up to date. */
2669 post_create_inferior (¤t_target
, from_tty
);
2674 /* Initialize static vars when a new inferior begins. */
2677 init_wait_for_inferior (void)
2679 /* These are meaningless until the first time through wait_for_inferior. */
2681 breakpoint_init_inferior (inf_starting
);
2683 clear_proceed_status (0);
2685 target_last_wait_ptid
= minus_one_ptid
;
2687 previous_inferior_ptid
= inferior_ptid
;
2689 /* Discard any skipped inlined frames. */
2690 clear_inline_frame_state (minus_one_ptid
);
2694 /* This enum encodes possible reasons for doing a target_wait, so that
2695 wfi can call target_wait in one place. (Ultimately the call will be
2696 moved out of the infinite loop entirely.) */
2700 infwait_normal_state
,
2701 infwait_step_watch_state
,
2702 infwait_nonstep_watch_state
2705 /* Current inferior wait state. */
2706 static enum infwait_states infwait_state
;
2708 /* Data to be passed around while handling an event. This data is
2709 discarded between events. */
2710 struct execution_control_state
2713 /* The thread that got the event, if this was a thread event; NULL
2715 struct thread_info
*event_thread
;
2717 struct target_waitstatus ws
;
2718 int stop_func_filled_in
;
2719 CORE_ADDR stop_func_start
;
2720 CORE_ADDR stop_func_end
;
2721 const char *stop_func_name
;
2724 /* True if the event thread hit the single-step breakpoint of
2725 another thread. Thus the event doesn't cause a stop, the thread
2726 needs to be single-stepped past the single-step breakpoint before
2727 we can switch back to the original stepping thread. */
2728 int hit_singlestep_breakpoint
;
2731 static void handle_inferior_event (struct execution_control_state
*ecs
);
2733 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2734 struct execution_control_state
*ecs
);
2735 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2736 struct execution_control_state
*ecs
);
2737 static void handle_signal_stop (struct execution_control_state
*ecs
);
2738 static void check_exception_resume (struct execution_control_state
*,
2739 struct frame_info
*);
2741 static void end_stepping_range (struct execution_control_state
*ecs
);
2742 static void stop_waiting (struct execution_control_state
*ecs
);
2743 static void prepare_to_wait (struct execution_control_state
*ecs
);
2744 static void keep_going (struct execution_control_state
*ecs
);
2745 static void process_event_stop_test (struct execution_control_state
*ecs
);
2746 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
2748 /* Callback for iterate over threads. If the thread is stopped, but
2749 the user/frontend doesn't know about that yet, go through
2750 normal_stop, as if the thread had just stopped now. ARG points at
2751 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2752 ptid_is_pid(PTID) is true, applies to all threads of the process
2753 pointed at by PTID. Otherwise, apply only to the thread pointed by
2757 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2759 ptid_t ptid
= * (ptid_t
*) arg
;
2761 if ((ptid_equal (info
->ptid
, ptid
)
2762 || ptid_equal (minus_one_ptid
, ptid
)
2763 || (ptid_is_pid (ptid
)
2764 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2765 && is_running (info
->ptid
)
2766 && !is_executing (info
->ptid
))
2768 struct cleanup
*old_chain
;
2769 struct execution_control_state ecss
;
2770 struct execution_control_state
*ecs
= &ecss
;
2772 memset (ecs
, 0, sizeof (*ecs
));
2774 old_chain
= make_cleanup_restore_current_thread ();
2776 overlay_cache_invalid
= 1;
2777 /* Flush target cache before starting to handle each event.
2778 Target was running and cache could be stale. This is just a
2779 heuristic. Running threads may modify target memory, but we
2780 don't get any event. */
2781 target_dcache_invalidate ();
2783 /* Go through handle_inferior_event/normal_stop, so we always
2784 have consistent output as if the stop event had been
2786 ecs
->ptid
= info
->ptid
;
2787 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2788 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2789 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
2791 handle_inferior_event (ecs
);
2793 if (!ecs
->wait_some_more
)
2795 struct thread_info
*tp
;
2799 /* Finish off the continuations. */
2800 tp
= inferior_thread ();
2801 do_all_intermediate_continuations_thread (tp
, 1);
2802 do_all_continuations_thread (tp
, 1);
2805 do_cleanups (old_chain
);
2811 /* This function is attached as a "thread_stop_requested" observer.
2812 Cleanup local state that assumed the PTID was to be resumed, and
2813 report the stop to the frontend. */
2816 infrun_thread_stop_requested (ptid_t ptid
)
2818 struct displaced_step_inferior_state
*displaced
;
2820 /* PTID was requested to stop. Remove it from the displaced
2821 stepping queue, so we don't try to resume it automatically. */
2823 for (displaced
= displaced_step_inferior_states
;
2825 displaced
= displaced
->next
)
2827 struct displaced_step_request
*it
, **prev_next_p
;
2829 it
= displaced
->step_request_queue
;
2830 prev_next_p
= &displaced
->step_request_queue
;
2833 if (ptid_match (it
->ptid
, ptid
))
2835 *prev_next_p
= it
->next
;
2841 prev_next_p
= &it
->next
;
2848 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2852 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2854 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2855 nullify_last_target_wait_ptid ();
2858 /* Delete the step resume, single-step and longjmp/exception resume
2859 breakpoints of TP. */
2862 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
2864 delete_step_resume_breakpoint (tp
);
2865 delete_exception_resume_breakpoint (tp
);
2866 delete_single_step_breakpoints (tp
);
2869 /* If the target still has execution, call FUNC for each thread that
2870 just stopped. In all-stop, that's all the non-exited threads; in
2871 non-stop, that's the current thread, only. */
2873 typedef void (*for_each_just_stopped_thread_callback_func
)
2874 (struct thread_info
*tp
);
2877 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
2879 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
2884 /* If in non-stop mode, only the current thread stopped. */
2885 func (inferior_thread ());
2889 struct thread_info
*tp
;
2891 /* In all-stop mode, all threads have stopped. */
2892 ALL_NON_EXITED_THREADS (tp
)
2899 /* Delete the step resume and longjmp/exception resume breakpoints of
2900 the threads that just stopped. */
2903 delete_just_stopped_threads_infrun_breakpoints (void)
2905 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
2908 /* Delete the single-step breakpoints of the threads that just
2912 delete_just_stopped_threads_single_step_breakpoints (void)
2914 for_each_just_stopped_thread (delete_single_step_breakpoints
);
2917 /* A cleanup wrapper. */
2920 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
2922 delete_just_stopped_threads_infrun_breakpoints ();
2925 /* Pretty print the results of target_wait, for debugging purposes. */
2928 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
2929 const struct target_waitstatus
*ws
)
2931 char *status_string
= target_waitstatus_to_string (ws
);
2932 struct ui_file
*tmp_stream
= mem_fileopen ();
2935 /* The text is split over several lines because it was getting too long.
2936 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2937 output as a unit; we want only one timestamp printed if debug_timestamp
2940 fprintf_unfiltered (tmp_stream
,
2941 "infrun: target_wait (%d", ptid_get_pid (waiton_ptid
));
2942 if (ptid_get_pid (waiton_ptid
) != -1)
2943 fprintf_unfiltered (tmp_stream
,
2944 " [%s]", target_pid_to_str (waiton_ptid
));
2945 fprintf_unfiltered (tmp_stream
, ", status) =\n");
2946 fprintf_unfiltered (tmp_stream
,
2947 "infrun: %d [%s],\n",
2948 ptid_get_pid (result_ptid
),
2949 target_pid_to_str (result_ptid
));
2950 fprintf_unfiltered (tmp_stream
,
2954 text
= ui_file_xstrdup (tmp_stream
, NULL
);
2956 /* This uses %s in part to handle %'s in the text, but also to avoid
2957 a gcc error: the format attribute requires a string literal. */
2958 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
2960 xfree (status_string
);
2962 ui_file_delete (tmp_stream
);
2965 /* Prepare and stabilize the inferior for detaching it. E.g.,
2966 detaching while a thread is displaced stepping is a recipe for
2967 crashing it, as nothing would readjust the PC out of the scratch
2971 prepare_for_detach (void)
2973 struct inferior
*inf
= current_inferior ();
2974 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
2975 struct cleanup
*old_chain_1
;
2976 struct displaced_step_inferior_state
*displaced
;
2978 displaced
= get_displaced_stepping_state (inf
->pid
);
2980 /* Is any thread of this process displaced stepping? If not,
2981 there's nothing else to do. */
2982 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
2986 fprintf_unfiltered (gdb_stdlog
,
2987 "displaced-stepping in-process while detaching");
2989 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
2992 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
2994 struct cleanup
*old_chain_2
;
2995 struct execution_control_state ecss
;
2996 struct execution_control_state
*ecs
;
2999 memset (ecs
, 0, sizeof (*ecs
));
3001 overlay_cache_invalid
= 1;
3002 /* Flush target cache before starting to handle each event.
3003 Target was running and cache could be stale. This is just a
3004 heuristic. Running threads may modify target memory, but we
3005 don't get any event. */
3006 target_dcache_invalidate ();
3008 if (deprecated_target_wait_hook
)
3009 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
3011 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
3014 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3016 /* If an error happens while handling the event, propagate GDB's
3017 knowledge of the executing state to the frontend/user running
3019 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3022 /* Now figure out what to do with the result of the result. */
3023 handle_inferior_event (ecs
);
3025 /* No error, don't finish the state yet. */
3026 discard_cleanups (old_chain_2
);
3028 /* Breakpoints and watchpoints are not installed on the target
3029 at this point, and signals are passed directly to the
3030 inferior, so this must mean the process is gone. */
3031 if (!ecs
->wait_some_more
)
3033 discard_cleanups (old_chain_1
);
3034 error (_("Program exited while detaching"));
3038 discard_cleanups (old_chain_1
);
3041 /* Wait for control to return from inferior to debugger.
3043 If inferior gets a signal, we may decide to start it up again
3044 instead of returning. That is why there is a loop in this function.
3045 When this function actually returns it means the inferior
3046 should be left stopped and GDB should read more commands. */
3049 wait_for_inferior (void)
3051 struct cleanup
*old_cleanups
;
3055 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3058 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3063 struct execution_control_state ecss
;
3064 struct execution_control_state
*ecs
= &ecss
;
3065 struct cleanup
*old_chain
;
3066 ptid_t waiton_ptid
= minus_one_ptid
;
3068 memset (ecs
, 0, sizeof (*ecs
));
3070 overlay_cache_invalid
= 1;
3072 /* Flush target cache before starting to handle each event.
3073 Target was running and cache could be stale. This is just a
3074 heuristic. Running threads may modify target memory, but we
3075 don't get any event. */
3076 target_dcache_invalidate ();
3078 if (deprecated_target_wait_hook
)
3079 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
3081 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
3084 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3086 /* If an error happens while handling the event, propagate GDB's
3087 knowledge of the executing state to the frontend/user running
3089 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3091 /* Now figure out what to do with the result of the result. */
3092 handle_inferior_event (ecs
);
3094 /* No error, don't finish the state yet. */
3095 discard_cleanups (old_chain
);
3097 if (!ecs
->wait_some_more
)
3101 do_cleanups (old_cleanups
);
3104 /* Cleanup that reinstalls the readline callback handler, if the
3105 target is running in the background. If while handling the target
3106 event something triggered a secondary prompt, like e.g., a
3107 pagination prompt, we'll have removed the callback handler (see
3108 gdb_readline_wrapper_line). Need to do this as we go back to the
3109 event loop, ready to process further input. Note this has no
3110 effect if the handler hasn't actually been removed, because calling
3111 rl_callback_handler_install resets the line buffer, thus losing
3115 reinstall_readline_callback_handler_cleanup (void *arg
)
3117 if (async_command_editing_p
&& !sync_execution
)
3118 gdb_rl_callback_handler_reinstall ();
3121 /* Asynchronous version of wait_for_inferior. It is called by the
3122 event loop whenever a change of state is detected on the file
3123 descriptor corresponding to the target. It can be called more than
3124 once to complete a single execution command. In such cases we need
3125 to keep the state in a global variable ECSS. If it is the last time
3126 that this function is called for a single execution command, then
3127 report to the user that the inferior has stopped, and do the
3128 necessary cleanups. */
3131 fetch_inferior_event (void *client_data
)
3133 struct execution_control_state ecss
;
3134 struct execution_control_state
*ecs
= &ecss
;
3135 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3136 struct cleanup
*ts_old_chain
;
3137 int was_sync
= sync_execution
;
3139 ptid_t waiton_ptid
= minus_one_ptid
;
3141 memset (ecs
, 0, sizeof (*ecs
));
3143 /* End up with readline processing input, if necessary. */
3144 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3146 /* We're handling a live event, so make sure we're doing live
3147 debugging. If we're looking at traceframes while the target is
3148 running, we're going to need to get back to that mode after
3149 handling the event. */
3152 make_cleanup_restore_current_traceframe ();
3153 set_current_traceframe (-1);
3157 /* In non-stop mode, the user/frontend should not notice a thread
3158 switch due to internal events. Make sure we reverse to the
3159 user selected thread and frame after handling the event and
3160 running any breakpoint commands. */
3161 make_cleanup_restore_current_thread ();
3163 overlay_cache_invalid
= 1;
3164 /* Flush target cache before starting to handle each event. Target
3165 was running and cache could be stale. This is just a heuristic.
3166 Running threads may modify target memory, but we don't get any
3168 target_dcache_invalidate ();
3170 make_cleanup_restore_integer (&execution_direction
);
3171 execution_direction
= target_execution_direction ();
3173 if (deprecated_target_wait_hook
)
3175 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3177 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3180 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3182 /* If an error happens while handling the event, propagate GDB's
3183 knowledge of the executing state to the frontend/user running
3186 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3188 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3190 /* Get executed before make_cleanup_restore_current_thread above to apply
3191 still for the thread which has thrown the exception. */
3192 make_bpstat_clear_actions_cleanup ();
3194 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3196 /* Now figure out what to do with the result of the result. */
3197 handle_inferior_event (ecs
);
3199 if (!ecs
->wait_some_more
)
3201 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3203 delete_just_stopped_threads_infrun_breakpoints ();
3205 /* We may not find an inferior if this was a process exit. */
3206 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3209 if (target_has_execution
3210 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
3211 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3212 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3213 && ecs
->event_thread
->step_multi
3214 && ecs
->event_thread
->control
.stop_step
)
3215 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
3218 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3223 /* No error, don't finish the thread states yet. */
3224 discard_cleanups (ts_old_chain
);
3226 /* Revert thread and frame. */
3227 do_cleanups (old_chain
);
3229 /* If the inferior was in sync execution mode, and now isn't,
3230 restore the prompt (a synchronous execution command has finished,
3231 and we're ready for input). */
3232 if (interpreter_async
&& was_sync
&& !sync_execution
)
3233 observer_notify_sync_execution_done ();
3237 && exec_done_display_p
3238 && (ptid_equal (inferior_ptid
, null_ptid
)
3239 || !is_running (inferior_ptid
)))
3240 printf_unfiltered (_("completed.\n"));
3243 /* Record the frame and location we're currently stepping through. */
3245 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3247 struct thread_info
*tp
= inferior_thread ();
3249 tp
->control
.step_frame_id
= get_frame_id (frame
);
3250 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
3252 tp
->current_symtab
= sal
.symtab
;
3253 tp
->current_line
= sal
.line
;
3256 /* Clear context switchable stepping state. */
3259 init_thread_stepping_state (struct thread_info
*tss
)
3261 tss
->stepped_breakpoint
= 0;
3262 tss
->stepping_over_breakpoint
= 0;
3263 tss
->stepping_over_watchpoint
= 0;
3264 tss
->step_after_step_resume_breakpoint
= 0;
3267 /* Set the cached copy of the last ptid/waitstatus. */
3270 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
3272 target_last_wait_ptid
= ptid
;
3273 target_last_waitstatus
= status
;
3276 /* Return the cached copy of the last pid/waitstatus returned by
3277 target_wait()/deprecated_target_wait_hook(). The data is actually
3278 cached by handle_inferior_event(), which gets called immediately
3279 after target_wait()/deprecated_target_wait_hook(). */
3282 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
3284 *ptidp
= target_last_wait_ptid
;
3285 *status
= target_last_waitstatus
;
3289 nullify_last_target_wait_ptid (void)
3291 target_last_wait_ptid
= minus_one_ptid
;
3294 /* Switch thread contexts. */
3297 context_switch (ptid_t ptid
)
3299 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
3301 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
3302 target_pid_to_str (inferior_ptid
));
3303 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
3304 target_pid_to_str (ptid
));
3307 switch_to_thread (ptid
);
3311 adjust_pc_after_break (struct execution_control_state
*ecs
)
3313 struct regcache
*regcache
;
3314 struct gdbarch
*gdbarch
;
3315 struct address_space
*aspace
;
3316 CORE_ADDR breakpoint_pc
, decr_pc
;
3318 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
3319 we aren't, just return.
3321 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
3322 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
3323 implemented by software breakpoints should be handled through the normal
3326 NOTE drow/2004-01-31: On some targets, breakpoints may generate
3327 different signals (SIGILL or SIGEMT for instance), but it is less
3328 clear where the PC is pointing afterwards. It may not match
3329 gdbarch_decr_pc_after_break. I don't know any specific target that
3330 generates these signals at breakpoints (the code has been in GDB since at
3331 least 1992) so I can not guess how to handle them here.
3333 In earlier versions of GDB, a target with
3334 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
3335 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
3336 target with both of these set in GDB history, and it seems unlikely to be
3337 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
3339 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
3342 if (ecs
->ws
.value
.sig
!= GDB_SIGNAL_TRAP
)
3345 /* In reverse execution, when a breakpoint is hit, the instruction
3346 under it has already been de-executed. The reported PC always
3347 points at the breakpoint address, so adjusting it further would
3348 be wrong. E.g., consider this case on a decr_pc_after_break == 1
3351 B1 0x08000000 : INSN1
3352 B2 0x08000001 : INSN2
3354 PC -> 0x08000003 : INSN4
3356 Say you're stopped at 0x08000003 as above. Reverse continuing
3357 from that point should hit B2 as below. Reading the PC when the
3358 SIGTRAP is reported should read 0x08000001 and INSN2 should have
3359 been de-executed already.
3361 B1 0x08000000 : INSN1
3362 B2 PC -> 0x08000001 : INSN2
3366 We can't apply the same logic as for forward execution, because
3367 we would wrongly adjust the PC to 0x08000000, since there's a
3368 breakpoint at PC - 1. We'd then report a hit on B1, although
3369 INSN1 hadn't been de-executed yet. Doing nothing is the correct
3371 if (execution_direction
== EXEC_REVERSE
)
3374 /* If this target does not decrement the PC after breakpoints, then
3375 we have nothing to do. */
3376 regcache
= get_thread_regcache (ecs
->ptid
);
3377 gdbarch
= get_regcache_arch (regcache
);
3379 decr_pc
= target_decr_pc_after_break (gdbarch
);
3383 aspace
= get_regcache_aspace (regcache
);
3385 /* Find the location where (if we've hit a breakpoint) the
3386 breakpoint would be. */
3387 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
3389 /* Check whether there actually is a software breakpoint inserted at
3392 If in non-stop mode, a race condition is possible where we've
3393 removed a breakpoint, but stop events for that breakpoint were
3394 already queued and arrive later. To suppress those spurious
3395 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3396 and retire them after a number of stop events are reported. */
3397 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3398 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3400 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
3402 if (record_full_is_used ())
3403 record_full_gdb_operation_disable_set ();
3405 /* When using hardware single-step, a SIGTRAP is reported for both
3406 a completed single-step and a software breakpoint. Need to
3407 differentiate between the two, as the latter needs adjusting
3408 but the former does not.
3410 The SIGTRAP can be due to a completed hardware single-step only if
3411 - we didn't insert software single-step breakpoints
3412 - the thread to be examined is still the current thread
3413 - this thread is currently being stepped
3415 If any of these events did not occur, we must have stopped due
3416 to hitting a software breakpoint, and have to back up to the
3419 As a special case, we could have hardware single-stepped a
3420 software breakpoint. In this case (prev_pc == breakpoint_pc),
3421 we also need to back up to the breakpoint address. */
3423 if (thread_has_single_step_breakpoints_set (ecs
->event_thread
)
3424 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
3425 || !currently_stepping (ecs
->event_thread
)
3426 || (ecs
->event_thread
->stepped_breakpoint
3427 && ecs
->event_thread
->prev_pc
== breakpoint_pc
))
3428 regcache_write_pc (regcache
, breakpoint_pc
);
3430 do_cleanups (old_cleanups
);
3435 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3437 for (frame
= get_prev_frame (frame
);
3439 frame
= get_prev_frame (frame
))
3441 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3443 if (get_frame_type (frame
) != INLINE_FRAME
)
3450 /* Auxiliary function that handles syscall entry/return events.
3451 It returns 1 if the inferior should keep going (and GDB
3452 should ignore the event), or 0 if the event deserves to be
3456 handle_syscall_event (struct execution_control_state
*ecs
)
3458 struct regcache
*regcache
;
3461 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3462 context_switch (ecs
->ptid
);
3464 regcache
= get_thread_regcache (ecs
->ptid
);
3465 syscall_number
= ecs
->ws
.value
.syscall_number
;
3466 stop_pc
= regcache_read_pc (regcache
);
3468 if (catch_syscall_enabled () > 0
3469 && catching_syscall_number (syscall_number
) > 0)
3472 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3475 ecs
->event_thread
->control
.stop_bpstat
3476 = bpstat_stop_status (get_regcache_aspace (regcache
),
3477 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3479 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3481 /* Catchpoint hit. */
3486 /* If no catchpoint triggered for this, then keep going. */
3491 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3494 fill_in_stop_func (struct gdbarch
*gdbarch
,
3495 struct execution_control_state
*ecs
)
3497 if (!ecs
->stop_func_filled_in
)
3499 /* Don't care about return value; stop_func_start and stop_func_name
3500 will both be 0 if it doesn't work. */
3501 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3502 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3503 ecs
->stop_func_start
3504 += gdbarch_deprecated_function_start_offset (gdbarch
);
3506 if (gdbarch_skip_entrypoint_p (gdbarch
))
3507 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
3508 ecs
->stop_func_start
);
3510 ecs
->stop_func_filled_in
= 1;
3515 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
3517 static enum stop_kind
3518 get_inferior_stop_soon (ptid_t ptid
)
3520 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ptid
));
3522 gdb_assert (inf
!= NULL
);
3523 return inf
->control
.stop_soon
;
3526 /* Given an execution control state that has been freshly filled in by
3527 an event from the inferior, figure out what it means and take
3530 The alternatives are:
3532 1) stop_waiting and return; to really stop and return to the
3535 2) keep_going and return; to wait for the next event (set
3536 ecs->event_thread->stepping_over_breakpoint to 1 to single step
3540 handle_inferior_event (struct execution_control_state
*ecs
)
3542 enum stop_kind stop_soon
;
3544 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3546 /* We had an event in the inferior, but we are not interested in
3547 handling it at this level. The lower layers have already
3548 done what needs to be done, if anything.
3550 One of the possible circumstances for this is when the
3551 inferior produces output for the console. The inferior has
3552 not stopped, and we are ignoring the event. Another possible
3553 circumstance is any event which the lower level knows will be
3554 reported multiple times without an intervening resume. */
3556 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3557 prepare_to_wait (ecs
);
3561 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3562 && target_can_async_p () && !sync_execution
)
3564 /* There were no unwaited-for children left in the target, but,
3565 we're not synchronously waiting for events either. Just
3566 ignore. Otherwise, if we were running a synchronous
3567 execution command, we need to cancel it and give the user
3568 back the terminal. */
3570 fprintf_unfiltered (gdb_stdlog
,
3571 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3572 prepare_to_wait (ecs
);
3576 /* Cache the last pid/waitstatus. */
3577 set_last_target_status (ecs
->ptid
, ecs
->ws
);
3579 /* Always clear state belonging to the previous time we stopped. */
3580 stop_stack_dummy
= STOP_NONE
;
3582 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3584 /* No unwaited-for children left. IOW, all resumed children
3587 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3589 stop_print_frame
= 0;
3594 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3595 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
3597 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3598 /* If it's a new thread, add it to the thread database. */
3599 if (ecs
->event_thread
== NULL
)
3600 ecs
->event_thread
= add_thread (ecs
->ptid
);
3602 /* Disable range stepping. If the next step request could use a
3603 range, this will be end up re-enabled then. */
3604 ecs
->event_thread
->control
.may_range_step
= 0;
3607 /* Dependent on valid ECS->EVENT_THREAD. */
3608 adjust_pc_after_break (ecs
);
3610 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3611 reinit_frame_cache ();
3613 breakpoint_retire_moribund ();
3615 /* First, distinguish signals caused by the debugger from signals
3616 that have to do with the program's own actions. Note that
3617 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3618 on the operating system version. Here we detect when a SIGILL or
3619 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3620 something similar for SIGSEGV, since a SIGSEGV will be generated
3621 when we're trying to execute a breakpoint instruction on a
3622 non-executable stack. This happens for call dummy breakpoints
3623 for architectures like SPARC that place call dummies on the
3625 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3626 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3627 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3628 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3630 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3632 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3633 regcache_read_pc (regcache
)))
3636 fprintf_unfiltered (gdb_stdlog
,
3637 "infrun: Treating signal as SIGTRAP\n");
3638 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3642 /* Mark the non-executing threads accordingly. In all-stop, all
3643 threads of all processes are stopped when we get any event
3644 reported. In non-stop mode, only the event thread stops. If
3645 we're handling a process exit in non-stop mode, there's nothing
3646 to do, as threads of the dead process are gone, and threads of
3647 any other process were left running. */
3649 set_executing (minus_one_ptid
, 0);
3650 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3651 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3652 set_executing (ecs
->ptid
, 0);
3654 switch (ecs
->ws
.kind
)
3656 case TARGET_WAITKIND_LOADED
:
3658 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3659 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3660 context_switch (ecs
->ptid
);
3661 /* Ignore gracefully during startup of the inferior, as it might
3662 be the shell which has just loaded some objects, otherwise
3663 add the symbols for the newly loaded objects. Also ignore at
3664 the beginning of an attach or remote session; we will query
3665 the full list of libraries once the connection is
3668 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
3669 if (stop_soon
== NO_STOP_QUIETLY
)
3671 struct regcache
*regcache
;
3673 regcache
= get_thread_regcache (ecs
->ptid
);
3675 handle_solib_event ();
3677 ecs
->event_thread
->control
.stop_bpstat
3678 = bpstat_stop_status (get_regcache_aspace (regcache
),
3679 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3681 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3683 /* A catchpoint triggered. */
3684 process_event_stop_test (ecs
);
3688 /* If requested, stop when the dynamic linker notifies
3689 gdb of events. This allows the user to get control
3690 and place breakpoints in initializer routines for
3691 dynamically loaded objects (among other things). */
3692 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3693 if (stop_on_solib_events
)
3695 /* Make sure we print "Stopped due to solib-event" in
3697 stop_print_frame
= 1;
3704 /* If we are skipping through a shell, or through shared library
3705 loading that we aren't interested in, resume the program. If
3706 we're running the program normally, also resume. */
3707 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3709 /* Loading of shared libraries might have changed breakpoint
3710 addresses. Make sure new breakpoints are inserted. */
3711 if (stop_soon
== NO_STOP_QUIETLY
)
3712 insert_breakpoints ();
3713 resume (0, GDB_SIGNAL_0
);
3714 prepare_to_wait (ecs
);
3718 /* But stop if we're attaching or setting up a remote
3720 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3721 || stop_soon
== STOP_QUIETLY_REMOTE
)
3724 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3729 internal_error (__FILE__
, __LINE__
,
3730 _("unhandled stop_soon: %d"), (int) stop_soon
);
3732 case TARGET_WAITKIND_SPURIOUS
:
3734 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3735 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3736 context_switch (ecs
->ptid
);
3737 resume (0, GDB_SIGNAL_0
);
3738 prepare_to_wait (ecs
);
3741 case TARGET_WAITKIND_EXITED
:
3742 case TARGET_WAITKIND_SIGNALLED
:
3745 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3746 fprintf_unfiltered (gdb_stdlog
,
3747 "infrun: TARGET_WAITKIND_EXITED\n");
3749 fprintf_unfiltered (gdb_stdlog
,
3750 "infrun: TARGET_WAITKIND_SIGNALLED\n");
3753 inferior_ptid
= ecs
->ptid
;
3754 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3755 set_current_program_space (current_inferior ()->pspace
);
3756 handle_vfork_child_exec_or_exit (0);
3757 target_terminal_ours (); /* Must do this before mourn anyway. */
3759 /* Clearing any previous state of convenience variables. */
3760 clear_exit_convenience_vars ();
3762 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3764 /* Record the exit code in the convenience variable $_exitcode, so
3765 that the user can inspect this again later. */
3766 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3767 (LONGEST
) ecs
->ws
.value
.integer
);
3769 /* Also record this in the inferior itself. */
3770 current_inferior ()->has_exit_code
= 1;
3771 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3773 /* Support the --return-child-result option. */
3774 return_child_result_value
= ecs
->ws
.value
.integer
;
3776 observer_notify_exited (ecs
->ws
.value
.integer
);
3780 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3781 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3783 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
3785 /* Set the value of the internal variable $_exitsignal,
3786 which holds the signal uncaught by the inferior. */
3787 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
3788 gdbarch_gdb_signal_to_target (gdbarch
,
3789 ecs
->ws
.value
.sig
));
3793 /* We don't have access to the target's method used for
3794 converting between signal numbers (GDB's internal
3795 representation <-> target's representation).
3796 Therefore, we cannot do a good job at displaying this
3797 information to the user. It's better to just warn
3798 her about it (if infrun debugging is enabled), and
3801 fprintf_filtered (gdb_stdlog
, _("\
3802 Cannot fill $_exitsignal with the correct signal number.\n"));
3805 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
3808 gdb_flush (gdb_stdout
);
3809 target_mourn_inferior ();
3810 stop_print_frame
= 0;
3814 /* The following are the only cases in which we keep going;
3815 the above cases end in a continue or goto. */
3816 case TARGET_WAITKIND_FORKED
:
3817 case TARGET_WAITKIND_VFORKED
:
3820 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3821 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3823 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
3826 /* Check whether the inferior is displaced stepping. */
3828 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3829 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3830 struct displaced_step_inferior_state
*displaced
3831 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3833 /* If checking displaced stepping is supported, and thread
3834 ecs->ptid is displaced stepping. */
3835 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3837 struct inferior
*parent_inf
3838 = find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3839 struct regcache
*child_regcache
;
3840 CORE_ADDR parent_pc
;
3842 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3843 indicating that the displaced stepping of syscall instruction
3844 has been done. Perform cleanup for parent process here. Note
3845 that this operation also cleans up the child process for vfork,
3846 because their pages are shared. */
3847 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
3849 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3851 /* Restore scratch pad for child process. */
3852 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3855 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3856 the child's PC is also within the scratchpad. Set the child's PC
3857 to the parent's PC value, which has already been fixed up.
3858 FIXME: we use the parent's aspace here, although we're touching
3859 the child, because the child hasn't been added to the inferior
3860 list yet at this point. */
3863 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3865 parent_inf
->aspace
);
3866 /* Read PC value of parent process. */
3867 parent_pc
= regcache_read_pc (regcache
);
3869 if (debug_displaced
)
3870 fprintf_unfiltered (gdb_stdlog
,
3871 "displaced: write child pc from %s to %s\n",
3873 regcache_read_pc (child_regcache
)),
3874 paddress (gdbarch
, parent_pc
));
3876 regcache_write_pc (child_regcache
, parent_pc
);
3880 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3881 context_switch (ecs
->ptid
);
3883 /* Immediately detach breakpoints from the child before there's
3884 any chance of letting the user delete breakpoints from the
3885 breakpoint lists. If we don't do this early, it's easy to
3886 leave left over traps in the child, vis: "break foo; catch
3887 fork; c; <fork>; del; c; <child calls foo>". We only follow
3888 the fork on the last `continue', and by that time the
3889 breakpoint at "foo" is long gone from the breakpoint table.
3890 If we vforked, then we don't need to unpatch here, since both
3891 parent and child are sharing the same memory pages; we'll
3892 need to unpatch at follow/detach time instead to be certain
3893 that new breakpoints added between catchpoint hit time and
3894 vfork follow are detached. */
3895 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3897 /* This won't actually modify the breakpoint list, but will
3898 physically remove the breakpoints from the child. */
3899 detach_breakpoints (ecs
->ws
.value
.related_pid
);
3902 delete_just_stopped_threads_single_step_breakpoints ();
3904 /* In case the event is caught by a catchpoint, remember that
3905 the event is to be followed at the next resume of the thread,
3906 and not immediately. */
3907 ecs
->event_thread
->pending_follow
= ecs
->ws
;
3909 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3911 ecs
->event_thread
->control
.stop_bpstat
3912 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3913 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3915 /* If no catchpoint triggered for this, then keep going. Note
3916 that we're interested in knowing the bpstat actually causes a
3917 stop, not just if it may explain the signal. Software
3918 watchpoints, for example, always appear in the bpstat. */
3919 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3925 = (follow_fork_mode_string
== follow_fork_mode_child
);
3927 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3929 should_resume
= follow_fork ();
3932 child
= ecs
->ws
.value
.related_pid
;
3934 /* In non-stop mode, also resume the other branch. */
3935 if (non_stop
&& !detach_fork
)
3938 switch_to_thread (parent
);
3940 switch_to_thread (child
);
3942 ecs
->event_thread
= inferior_thread ();
3943 ecs
->ptid
= inferior_ptid
;
3948 switch_to_thread (child
);
3950 switch_to_thread (parent
);
3952 ecs
->event_thread
= inferior_thread ();
3953 ecs
->ptid
= inferior_ptid
;
3961 process_event_stop_test (ecs
);
3964 case TARGET_WAITKIND_VFORK_DONE
:
3965 /* Done with the shared memory region. Re-insert breakpoints in
3966 the parent, and keep going. */
3969 fprintf_unfiltered (gdb_stdlog
,
3970 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3972 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3973 context_switch (ecs
->ptid
);
3975 current_inferior ()->waiting_for_vfork_done
= 0;
3976 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
3977 /* This also takes care of reinserting breakpoints in the
3978 previously locked inferior. */
3982 case TARGET_WAITKIND_EXECD
:
3984 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
3986 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3987 context_switch (ecs
->ptid
);
3989 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3991 /* Do whatever is necessary to the parent branch of the vfork. */
3992 handle_vfork_child_exec_or_exit (1);
3994 /* This causes the eventpoints and symbol table to be reset.
3995 Must do this now, before trying to determine whether to
3997 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
3999 ecs
->event_thread
->control
.stop_bpstat
4000 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4001 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4003 /* Note that this may be referenced from inside
4004 bpstat_stop_status above, through inferior_has_execd. */
4005 xfree (ecs
->ws
.value
.execd_pathname
);
4006 ecs
->ws
.value
.execd_pathname
= NULL
;
4008 /* If no catchpoint triggered for this, then keep going. */
4009 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4011 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4015 process_event_stop_test (ecs
);
4018 /* Be careful not to try to gather much state about a thread
4019 that's in a syscall. It's frequently a losing proposition. */
4020 case TARGET_WAITKIND_SYSCALL_ENTRY
:
4022 fprintf_unfiltered (gdb_stdlog
,
4023 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
4024 /* Getting the current syscall number. */
4025 if (handle_syscall_event (ecs
) == 0)
4026 process_event_stop_test (ecs
);
4029 /* Before examining the threads further, step this thread to
4030 get it entirely out of the syscall. (We get notice of the
4031 event when the thread is just on the verge of exiting a
4032 syscall. Stepping one instruction seems to get it back
4034 case TARGET_WAITKIND_SYSCALL_RETURN
:
4036 fprintf_unfiltered (gdb_stdlog
,
4037 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
4038 if (handle_syscall_event (ecs
) == 0)
4039 process_event_stop_test (ecs
);
4042 case TARGET_WAITKIND_STOPPED
:
4044 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
4045 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
4046 handle_signal_stop (ecs
);
4049 case TARGET_WAITKIND_NO_HISTORY
:
4051 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
4052 /* Reverse execution: target ran out of history info. */
4054 delete_just_stopped_threads_single_step_breakpoints ();
4055 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4056 observer_notify_no_history ();
4062 /* Come here when the program has stopped with a signal. */
4065 handle_signal_stop (struct execution_control_state
*ecs
)
4067 struct frame_info
*frame
;
4068 struct gdbarch
*gdbarch
;
4069 int stopped_by_watchpoint
;
4070 enum stop_kind stop_soon
;
4073 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
4075 /* Do we need to clean up the state of a thread that has
4076 completed a displaced single-step? (Doing so usually affects
4077 the PC, so do it here, before we set stop_pc.) */
4078 displaced_step_fixup (ecs
->ptid
,
4079 ecs
->event_thread
->suspend
.stop_signal
);
4081 /* If we either finished a single-step or hit a breakpoint, but
4082 the user wanted this thread to be stopped, pretend we got a
4083 SIG0 (generic unsignaled stop). */
4084 if (ecs
->event_thread
->stop_requested
4085 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4086 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4088 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4092 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4093 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4094 struct cleanup
*old_chain
= save_inferior_ptid ();
4096 inferior_ptid
= ecs
->ptid
;
4098 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
4099 paddress (gdbarch
, stop_pc
));
4100 if (target_stopped_by_watchpoint ())
4104 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
4106 if (target_stopped_data_address (¤t_target
, &addr
))
4107 fprintf_unfiltered (gdb_stdlog
,
4108 "infrun: stopped data address = %s\n",
4109 paddress (gdbarch
, addr
));
4111 fprintf_unfiltered (gdb_stdlog
,
4112 "infrun: (no data address available)\n");
4115 do_cleanups (old_chain
);
4118 /* This is originated from start_remote(), start_inferior() and
4119 shared libraries hook functions. */
4120 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4121 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4123 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4124 context_switch (ecs
->ptid
);
4126 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4127 stop_print_frame
= 1;
4132 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4135 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4136 context_switch (ecs
->ptid
);
4138 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4139 stop_print_frame
= 0;
4144 /* This originates from attach_command(). We need to overwrite
4145 the stop_signal here, because some kernels don't ignore a
4146 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4147 See more comments in inferior.h. On the other hand, if we
4148 get a non-SIGSTOP, report it to the user - assume the backend
4149 will handle the SIGSTOP if it should show up later.
4151 Also consider that the attach is complete when we see a
4152 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4153 target extended-remote report it instead of a SIGSTOP
4154 (e.g. gdbserver). We already rely on SIGTRAP being our
4155 signal, so this is no exception.
4157 Also consider that the attach is complete when we see a
4158 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4159 the target to stop all threads of the inferior, in case the
4160 low level attach operation doesn't stop them implicitly. If
4161 they weren't stopped implicitly, then the stub will report a
4162 GDB_SIGNAL_0, meaning: stopped for no particular reason
4163 other than GDB's request. */
4164 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4165 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
4166 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4167 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
4169 stop_print_frame
= 1;
4171 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4175 /* See if something interesting happened to the non-current thread. If
4176 so, then switch to that thread. */
4177 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4180 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
4182 context_switch (ecs
->ptid
);
4184 if (deprecated_context_hook
)
4185 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
4188 /* At this point, get hold of the now-current thread's frame. */
4189 frame
= get_current_frame ();
4190 gdbarch
= get_frame_arch (frame
);
4192 /* Pull the single step breakpoints out of the target. */
4193 if (gdbarch_software_single_step_p (gdbarch
))
4195 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4197 struct regcache
*regcache
;
4198 struct address_space
*aspace
;
4201 regcache
= get_thread_regcache (ecs
->ptid
);
4202 aspace
= get_regcache_aspace (regcache
);
4203 pc
= regcache_read_pc (regcache
);
4205 /* However, before doing so, if this single-step breakpoint was
4206 actually for another thread, set this thread up for moving
4208 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
4211 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
4215 fprintf_unfiltered (gdb_stdlog
,
4216 "infrun: [%s] hit another thread's "
4217 "single-step breakpoint\n",
4218 target_pid_to_str (ecs
->ptid
));
4220 ecs
->hit_singlestep_breakpoint
= 1;
4227 fprintf_unfiltered (gdb_stdlog
,
4228 "infrun: [%s] hit its "
4229 "single-step breakpoint\n",
4230 target_pid_to_str (ecs
->ptid
));
4235 delete_just_stopped_threads_single_step_breakpoints ();
4238 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4239 && ecs
->event_thread
->control
.trap_expected
4240 && ecs
->event_thread
->stepping_over_watchpoint
)
4241 stopped_by_watchpoint
= 0;
4243 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
4245 /* If necessary, step over this watchpoint. We'll be back to display
4247 if (stopped_by_watchpoint
4248 && (target_have_steppable_watchpoint
4249 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
4251 /* At this point, we are stopped at an instruction which has
4252 attempted to write to a piece of memory under control of
4253 a watchpoint. The instruction hasn't actually executed
4254 yet. If we were to evaluate the watchpoint expression
4255 now, we would get the old value, and therefore no change
4256 would seem to have occurred.
4258 In order to make watchpoints work `right', we really need
4259 to complete the memory write, and then evaluate the
4260 watchpoint expression. We do this by single-stepping the
4263 It may not be necessary to disable the watchpoint to step over
4264 it. For example, the PA can (with some kernel cooperation)
4265 single step over a watchpoint without disabling the watchpoint.
4267 It is far more common to need to disable a watchpoint to step
4268 the inferior over it. If we have non-steppable watchpoints,
4269 we must disable the current watchpoint; it's simplest to
4270 disable all watchpoints.
4272 Any breakpoint at PC must also be stepped over -- if there's
4273 one, it will have already triggered before the watchpoint
4274 triggered, and we either already reported it to the user, or
4275 it didn't cause a stop and we called keep_going. In either
4276 case, if there was a breakpoint at PC, we must be trying to
4278 ecs
->event_thread
->stepping_over_watchpoint
= 1;
4283 ecs
->event_thread
->stepped_breakpoint
= 0;
4284 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4285 ecs
->event_thread
->stepping_over_watchpoint
= 0;
4286 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4287 ecs
->event_thread
->control
.stop_step
= 0;
4288 stop_print_frame
= 1;
4289 stopped_by_random_signal
= 0;
4291 /* Hide inlined functions starting here, unless we just performed stepi or
4292 nexti. After stepi and nexti, always show the innermost frame (not any
4293 inline function call sites). */
4294 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4296 struct address_space
*aspace
=
4297 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4299 /* skip_inline_frames is expensive, so we avoid it if we can
4300 determine that the address is one where functions cannot have
4301 been inlined. This improves performance with inferiors that
4302 load a lot of shared libraries, because the solib event
4303 breakpoint is defined as the address of a function (i.e. not
4304 inline). Note that we have to check the previous PC as well
4305 as the current one to catch cases when we have just
4306 single-stepped off a breakpoint prior to reinstating it.
4307 Note that we're assuming that the code we single-step to is
4308 not inline, but that's not definitive: there's nothing
4309 preventing the event breakpoint function from containing
4310 inlined code, and the single-step ending up there. If the
4311 user had set a breakpoint on that inlined code, the missing
4312 skip_inline_frames call would break things. Fortunately
4313 that's an extremely unlikely scenario. */
4314 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4315 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4316 && ecs
->event_thread
->control
.trap_expected
4317 && pc_at_non_inline_function (aspace
,
4318 ecs
->event_thread
->prev_pc
,
4321 skip_inline_frames (ecs
->ptid
);
4323 /* Re-fetch current thread's frame in case that invalidated
4325 frame
= get_current_frame ();
4326 gdbarch
= get_frame_arch (frame
);
4330 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4331 && ecs
->event_thread
->control
.trap_expected
4332 && gdbarch_single_step_through_delay_p (gdbarch
)
4333 && currently_stepping (ecs
->event_thread
))
4335 /* We're trying to step off a breakpoint. Turns out that we're
4336 also on an instruction that needs to be stepped multiple
4337 times before it's been fully executing. E.g., architectures
4338 with a delay slot. It needs to be stepped twice, once for
4339 the instruction and once for the delay slot. */
4340 int step_through_delay
4341 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4343 if (debug_infrun
&& step_through_delay
)
4344 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4345 if (ecs
->event_thread
->control
.step_range_end
== 0
4346 && step_through_delay
)
4348 /* The user issued a continue when stopped at a breakpoint.
4349 Set up for another trap and get out of here. */
4350 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4354 else if (step_through_delay
)
4356 /* The user issued a step when stopped at a breakpoint.
4357 Maybe we should stop, maybe we should not - the delay
4358 slot *might* correspond to a line of source. In any
4359 case, don't decide that here, just set
4360 ecs->stepping_over_breakpoint, making sure we
4361 single-step again before breakpoints are re-inserted. */
4362 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4366 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4367 handles this event. */
4368 ecs
->event_thread
->control
.stop_bpstat
4369 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4370 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4372 /* Following in case break condition called a
4374 stop_print_frame
= 1;
4376 /* This is where we handle "moribund" watchpoints. Unlike
4377 software breakpoints traps, hardware watchpoint traps are
4378 always distinguishable from random traps. If no high-level
4379 watchpoint is associated with the reported stop data address
4380 anymore, then the bpstat does not explain the signal ---
4381 simply make sure to ignore it if `stopped_by_watchpoint' is
4385 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4386 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4388 && stopped_by_watchpoint
)
4389 fprintf_unfiltered (gdb_stdlog
,
4390 "infrun: no user watchpoint explains "
4391 "watchpoint SIGTRAP, ignoring\n");
4393 /* NOTE: cagney/2003-03-29: These checks for a random signal
4394 at one stage in the past included checks for an inferior
4395 function call's call dummy's return breakpoint. The original
4396 comment, that went with the test, read:
4398 ``End of a stack dummy. Some systems (e.g. Sony news) give
4399 another signal besides SIGTRAP, so check here as well as
4402 If someone ever tries to get call dummys on a
4403 non-executable stack to work (where the target would stop
4404 with something like a SIGSEGV), then those tests might need
4405 to be re-instated. Given, however, that the tests were only
4406 enabled when momentary breakpoints were not being used, I
4407 suspect that it won't be the case.
4409 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4410 be necessary for call dummies on a non-executable stack on
4413 /* See if the breakpoints module can explain the signal. */
4415 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4416 ecs
->event_thread
->suspend
.stop_signal
);
4418 /* If not, perhaps stepping/nexting can. */
4420 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4421 && currently_stepping (ecs
->event_thread
));
4423 /* Perhaps the thread hit a single-step breakpoint of _another_
4424 thread. Single-step breakpoints are transparent to the
4425 breakpoints module. */
4427 random_signal
= !ecs
->hit_singlestep_breakpoint
;
4429 /* No? Perhaps we got a moribund watchpoint. */
4431 random_signal
= !stopped_by_watchpoint
;
4433 /* For the program's own signals, act according to
4434 the signal handling tables. */
4438 /* Signal not for debugging purposes. */
4439 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
4440 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
4443 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
4444 gdb_signal_to_symbol_string (stop_signal
));
4446 stopped_by_random_signal
= 1;
4448 /* Always stop on signals if we're either just gaining control
4449 of the program, or the user explicitly requested this thread
4450 to remain stopped. */
4451 if (stop_soon
!= NO_STOP_QUIETLY
4452 || ecs
->event_thread
->stop_requested
4454 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4460 /* Notify observers the signal has "handle print" set. Note we
4461 returned early above if stopping; normal_stop handles the
4462 printing in that case. */
4463 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4465 /* The signal table tells us to print about this signal. */
4466 target_terminal_ours_for_output ();
4467 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
4468 target_terminal_inferior ();
4471 /* Clear the signal if it should not be passed. */
4472 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4473 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4475 if (ecs
->event_thread
->prev_pc
== stop_pc
4476 && ecs
->event_thread
->control
.trap_expected
4477 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4479 /* We were just starting a new sequence, attempting to
4480 single-step off of a breakpoint and expecting a SIGTRAP.
4481 Instead this signal arrives. This signal will take us out
4482 of the stepping range so GDB needs to remember to, when
4483 the signal handler returns, resume stepping off that
4485 /* To simplify things, "continue" is forced to use the same
4486 code paths as single-step - set a breakpoint at the
4487 signal return address and then, once hit, step off that
4490 fprintf_unfiltered (gdb_stdlog
,
4491 "infrun: signal arrived while stepping over "
4494 insert_hp_step_resume_breakpoint_at_frame (frame
);
4495 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4496 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4497 ecs
->event_thread
->control
.trap_expected
= 0;
4499 /* If we were nexting/stepping some other thread, switch to
4500 it, so that we don't continue it, losing control. */
4501 if (!switch_back_to_stepped_thread (ecs
))
4506 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4507 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4508 || ecs
->event_thread
->control
.step_range_end
== 1)
4509 && frame_id_eq (get_stack_frame_id (frame
),
4510 ecs
->event_thread
->control
.step_stack_frame_id
)
4511 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4513 /* The inferior is about to take a signal that will take it
4514 out of the single step range. Set a breakpoint at the
4515 current PC (which is presumably where the signal handler
4516 will eventually return) and then allow the inferior to
4519 Note that this is only needed for a signal delivered
4520 while in the single-step range. Nested signals aren't a
4521 problem as they eventually all return. */
4523 fprintf_unfiltered (gdb_stdlog
,
4524 "infrun: signal may take us out of "
4525 "single-step range\n");
4527 insert_hp_step_resume_breakpoint_at_frame (frame
);
4528 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4529 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4530 ecs
->event_thread
->control
.trap_expected
= 0;
4535 /* Note: step_resume_breakpoint may be non-NULL. This occures
4536 when either there's a nested signal, or when there's a
4537 pending signal enabled just as the signal handler returns
4538 (leaving the inferior at the step-resume-breakpoint without
4539 actually executing it). Either way continue until the
4540 breakpoint is really hit. */
4542 if (!switch_back_to_stepped_thread (ecs
))
4545 fprintf_unfiltered (gdb_stdlog
,
4546 "infrun: random signal, keep going\n");
4553 process_event_stop_test (ecs
);
4556 /* Come here when we've got some debug event / signal we can explain
4557 (IOW, not a random signal), and test whether it should cause a
4558 stop, or whether we should resume the inferior (transparently).
4559 E.g., could be a breakpoint whose condition evaluates false; we
4560 could be still stepping within the line; etc. */
4563 process_event_stop_test (struct execution_control_state
*ecs
)
4565 struct symtab_and_line stop_pc_sal
;
4566 struct frame_info
*frame
;
4567 struct gdbarch
*gdbarch
;
4568 CORE_ADDR jmp_buf_pc
;
4569 struct bpstat_what what
;
4571 /* Handle cases caused by hitting a breakpoint. */
4573 frame
= get_current_frame ();
4574 gdbarch
= get_frame_arch (frame
);
4576 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4578 if (what
.call_dummy
)
4580 stop_stack_dummy
= what
.call_dummy
;
4583 /* If we hit an internal event that triggers symbol changes, the
4584 current frame will be invalidated within bpstat_what (e.g., if we
4585 hit an internal solib event). Re-fetch it. */
4586 frame
= get_current_frame ();
4587 gdbarch
= get_frame_arch (frame
);
4589 switch (what
.main_action
)
4591 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4592 /* If we hit the breakpoint at longjmp while stepping, we
4593 install a momentary breakpoint at the target of the
4597 fprintf_unfiltered (gdb_stdlog
,
4598 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4600 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4602 if (what
.is_longjmp
)
4604 struct value
*arg_value
;
4606 /* If we set the longjmp breakpoint via a SystemTap probe,
4607 then use it to extract the arguments. The destination PC
4608 is the third argument to the probe. */
4609 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4612 jmp_buf_pc
= value_as_address (arg_value
);
4613 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
4615 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4616 || !gdbarch_get_longjmp_target (gdbarch
,
4617 frame
, &jmp_buf_pc
))
4620 fprintf_unfiltered (gdb_stdlog
,
4621 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4622 "(!gdbarch_get_longjmp_target)\n");
4627 /* Insert a breakpoint at resume address. */
4628 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4631 check_exception_resume (ecs
, frame
);
4635 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4637 struct frame_info
*init_frame
;
4639 /* There are several cases to consider.
4641 1. The initiating frame no longer exists. In this case we
4642 must stop, because the exception or longjmp has gone too
4645 2. The initiating frame exists, and is the same as the
4646 current frame. We stop, because the exception or longjmp
4649 3. The initiating frame exists and is different from the
4650 current frame. This means the exception or longjmp has
4651 been caught beneath the initiating frame, so keep going.
4653 4. longjmp breakpoint has been placed just to protect
4654 against stale dummy frames and user is not interested in
4655 stopping around longjmps. */
4658 fprintf_unfiltered (gdb_stdlog
,
4659 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4661 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4663 delete_exception_resume_breakpoint (ecs
->event_thread
);
4665 if (what
.is_longjmp
)
4667 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
4669 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
4677 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4681 struct frame_id current_id
4682 = get_frame_id (get_current_frame ());
4683 if (frame_id_eq (current_id
,
4684 ecs
->event_thread
->initiating_frame
))
4686 /* Case 2. Fall through. */
4696 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
4698 delete_step_resume_breakpoint (ecs
->event_thread
);
4700 end_stepping_range (ecs
);
4704 case BPSTAT_WHAT_SINGLE
:
4706 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4707 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4708 /* Still need to check other stuff, at least the case where we
4709 are stepping and step out of the right range. */
4712 case BPSTAT_WHAT_STEP_RESUME
:
4714 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4716 delete_step_resume_breakpoint (ecs
->event_thread
);
4717 if (ecs
->event_thread
->control
.proceed_to_finish
4718 && execution_direction
== EXEC_REVERSE
)
4720 struct thread_info
*tp
= ecs
->event_thread
;
4722 /* We are finishing a function in reverse, and just hit the
4723 step-resume breakpoint at the start address of the
4724 function, and we're almost there -- just need to back up
4725 by one more single-step, which should take us back to the
4727 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4731 fill_in_stop_func (gdbarch
, ecs
);
4732 if (stop_pc
== ecs
->stop_func_start
4733 && execution_direction
== EXEC_REVERSE
)
4735 /* We are stepping over a function call in reverse, and just
4736 hit the step-resume breakpoint at the start address of
4737 the function. Go back to single-stepping, which should
4738 take us back to the function call. */
4739 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4745 case BPSTAT_WHAT_STOP_NOISY
:
4747 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4748 stop_print_frame
= 1;
4750 /* Assume the thread stopped for a breapoint. We'll still check
4751 whether a/the breakpoint is there when the thread is next
4753 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4758 case BPSTAT_WHAT_STOP_SILENT
:
4760 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4761 stop_print_frame
= 0;
4763 /* Assume the thread stopped for a breapoint. We'll still check
4764 whether a/the breakpoint is there when the thread is next
4766 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4770 case BPSTAT_WHAT_HP_STEP_RESUME
:
4772 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4774 delete_step_resume_breakpoint (ecs
->event_thread
);
4775 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4777 /* Back when the step-resume breakpoint was inserted, we
4778 were trying to single-step off a breakpoint. Go back to
4780 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4781 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4787 case BPSTAT_WHAT_KEEP_CHECKING
:
4791 /* We come here if we hit a breakpoint but should not stop for it.
4792 Possibly we also were stepping and should stop for that. So fall
4793 through and test for stepping. But, if not stepping, do not
4796 /* In all-stop mode, if we're currently stepping but have stopped in
4797 some other thread, we need to switch back to the stepped thread. */
4798 if (switch_back_to_stepped_thread (ecs
))
4801 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4804 fprintf_unfiltered (gdb_stdlog
,
4805 "infrun: step-resume breakpoint is inserted\n");
4807 /* Having a step-resume breakpoint overrides anything
4808 else having to do with stepping commands until
4809 that breakpoint is reached. */
4814 if (ecs
->event_thread
->control
.step_range_end
== 0)
4817 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4818 /* Likewise if we aren't even stepping. */
4823 /* Re-fetch current thread's frame in case the code above caused
4824 the frame cache to be re-initialized, making our FRAME variable
4825 a dangling pointer. */
4826 frame
= get_current_frame ();
4827 gdbarch
= get_frame_arch (frame
);
4828 fill_in_stop_func (gdbarch
, ecs
);
4830 /* If stepping through a line, keep going if still within it.
4832 Note that step_range_end is the address of the first instruction
4833 beyond the step range, and NOT the address of the last instruction
4836 Note also that during reverse execution, we may be stepping
4837 through a function epilogue and therefore must detect when
4838 the current-frame changes in the middle of a line. */
4840 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4841 && (execution_direction
!= EXEC_REVERSE
4842 || frame_id_eq (get_frame_id (frame
),
4843 ecs
->event_thread
->control
.step_frame_id
)))
4847 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4848 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4849 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4851 /* Tentatively re-enable range stepping; `resume' disables it if
4852 necessary (e.g., if we're stepping over a breakpoint or we
4853 have software watchpoints). */
4854 ecs
->event_thread
->control
.may_range_step
= 1;
4856 /* When stepping backward, stop at beginning of line range
4857 (unless it's the function entry point, in which case
4858 keep going back to the call point). */
4859 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4860 && stop_pc
!= ecs
->stop_func_start
4861 && execution_direction
== EXEC_REVERSE
)
4862 end_stepping_range (ecs
);
4869 /* We stepped out of the stepping range. */
4871 /* If we are stepping at the source level and entered the runtime
4872 loader dynamic symbol resolution code...
4874 EXEC_FORWARD: we keep on single stepping until we exit the run
4875 time loader code and reach the callee's address.
4877 EXEC_REVERSE: we've already executed the callee (backward), and
4878 the runtime loader code is handled just like any other
4879 undebuggable function call. Now we need only keep stepping
4880 backward through the trampoline code, and that's handled further
4881 down, so there is nothing for us to do here. */
4883 if (execution_direction
!= EXEC_REVERSE
4884 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4885 && in_solib_dynsym_resolve_code (stop_pc
))
4887 CORE_ADDR pc_after_resolver
=
4888 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
4891 fprintf_unfiltered (gdb_stdlog
,
4892 "infrun: stepped into dynsym resolve code\n");
4894 if (pc_after_resolver
)
4896 /* Set up a step-resume breakpoint at the address
4897 indicated by SKIP_SOLIB_RESOLVER. */
4898 struct symtab_and_line sr_sal
;
4901 sr_sal
.pc
= pc_after_resolver
;
4902 sr_sal
.pspace
= get_frame_program_space (frame
);
4904 insert_step_resume_breakpoint_at_sal (gdbarch
,
4905 sr_sal
, null_frame_id
);
4912 if (ecs
->event_thread
->control
.step_range_end
!= 1
4913 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4914 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4915 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
4918 fprintf_unfiltered (gdb_stdlog
,
4919 "infrun: stepped into signal trampoline\n");
4920 /* The inferior, while doing a "step" or "next", has ended up in
4921 a signal trampoline (either by a signal being delivered or by
4922 the signal handler returning). Just single-step until the
4923 inferior leaves the trampoline (either by calling the handler
4929 /* If we're in the return path from a shared library trampoline,
4930 we want to proceed through the trampoline when stepping. */
4931 /* macro/2012-04-25: This needs to come before the subroutine
4932 call check below as on some targets return trampolines look
4933 like subroutine calls (MIPS16 return thunks). */
4934 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4935 stop_pc
, ecs
->stop_func_name
)
4936 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
4938 /* Determine where this trampoline returns. */
4939 CORE_ADDR real_stop_pc
;
4941 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4944 fprintf_unfiltered (gdb_stdlog
,
4945 "infrun: stepped into solib return tramp\n");
4947 /* Only proceed through if we know where it's going. */
4950 /* And put the step-breakpoint there and go until there. */
4951 struct symtab_and_line sr_sal
;
4953 init_sal (&sr_sal
); /* initialize to zeroes */
4954 sr_sal
.pc
= real_stop_pc
;
4955 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4956 sr_sal
.pspace
= get_frame_program_space (frame
);
4958 /* Do not specify what the fp should be when we stop since
4959 on some machines the prologue is where the new fp value
4961 insert_step_resume_breakpoint_at_sal (gdbarch
,
4962 sr_sal
, null_frame_id
);
4964 /* Restart without fiddling with the step ranges or
4971 /* Check for subroutine calls. The check for the current frame
4972 equalling the step ID is not necessary - the check of the
4973 previous frame's ID is sufficient - but it is a common case and
4974 cheaper than checking the previous frame's ID.
4976 NOTE: frame_id_eq will never report two invalid frame IDs as
4977 being equal, so to get into this block, both the current and
4978 previous frame must have valid frame IDs. */
4979 /* The outer_frame_id check is a heuristic to detect stepping
4980 through startup code. If we step over an instruction which
4981 sets the stack pointer from an invalid value to a valid value,
4982 we may detect that as a subroutine call from the mythical
4983 "outermost" function. This could be fixed by marking
4984 outermost frames as !stack_p,code_p,special_p. Then the
4985 initial outermost frame, before sp was valid, would
4986 have code_addr == &_start. See the comment in frame_id_eq
4988 if (!frame_id_eq (get_stack_frame_id (frame
),
4989 ecs
->event_thread
->control
.step_stack_frame_id
)
4990 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4991 ecs
->event_thread
->control
.step_stack_frame_id
)
4992 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
4994 || step_start_function
!= find_pc_function (stop_pc
))))
4996 CORE_ADDR real_stop_pc
;
4999 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
5001 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
5003 /* I presume that step_over_calls is only 0 when we're
5004 supposed to be stepping at the assembly language level
5005 ("stepi"). Just stop. */
5006 /* And this works the same backward as frontward. MVS */
5007 end_stepping_range (ecs
);
5011 /* Reverse stepping through solib trampolines. */
5013 if (execution_direction
== EXEC_REVERSE
5014 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
5015 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5016 || (ecs
->stop_func_start
== 0
5017 && in_solib_dynsym_resolve_code (stop_pc
))))
5019 /* Any solib trampoline code can be handled in reverse
5020 by simply continuing to single-step. We have already
5021 executed the solib function (backwards), and a few
5022 steps will take us back through the trampoline to the
5028 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5030 /* We're doing a "next".
5032 Normal (forward) execution: set a breakpoint at the
5033 callee's return address (the address at which the caller
5036 Reverse (backward) execution. set the step-resume
5037 breakpoint at the start of the function that we just
5038 stepped into (backwards), and continue to there. When we
5039 get there, we'll need to single-step back to the caller. */
5041 if (execution_direction
== EXEC_REVERSE
)
5043 /* If we're already at the start of the function, we've either
5044 just stepped backward into a single instruction function,
5045 or stepped back out of a signal handler to the first instruction
5046 of the function. Just keep going, which will single-step back
5048 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
5050 struct symtab_and_line sr_sal
;
5052 /* Normal function call return (static or dynamic). */
5054 sr_sal
.pc
= ecs
->stop_func_start
;
5055 sr_sal
.pspace
= get_frame_program_space (frame
);
5056 insert_step_resume_breakpoint_at_sal (gdbarch
,
5057 sr_sal
, null_frame_id
);
5061 insert_step_resume_breakpoint_at_caller (frame
);
5067 /* If we are in a function call trampoline (a stub between the
5068 calling routine and the real function), locate the real
5069 function. That's what tells us (a) whether we want to step
5070 into it at all, and (b) what prologue we want to run to the
5071 end of, if we do step into it. */
5072 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
5073 if (real_stop_pc
== 0)
5074 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
5075 if (real_stop_pc
!= 0)
5076 ecs
->stop_func_start
= real_stop_pc
;
5078 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
5080 struct symtab_and_line sr_sal
;
5083 sr_sal
.pc
= ecs
->stop_func_start
;
5084 sr_sal
.pspace
= get_frame_program_space (frame
);
5086 insert_step_resume_breakpoint_at_sal (gdbarch
,
5087 sr_sal
, null_frame_id
);
5092 /* If we have line number information for the function we are
5093 thinking of stepping into and the function isn't on the skip
5096 If there are several symtabs at that PC (e.g. with include
5097 files), just want to know whether *any* of them have line
5098 numbers. find_pc_line handles this. */
5100 struct symtab_and_line tmp_sal
;
5102 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5103 if (tmp_sal
.line
!= 0
5104 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
5107 if (execution_direction
== EXEC_REVERSE
)
5108 handle_step_into_function_backward (gdbarch
, ecs
);
5110 handle_step_into_function (gdbarch
, ecs
);
5115 /* If we have no line number and the step-stop-if-no-debug is
5116 set, we stop the step so that the user has a chance to switch
5117 in assembly mode. */
5118 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5119 && step_stop_if_no_debug
)
5121 end_stepping_range (ecs
);
5125 if (execution_direction
== EXEC_REVERSE
)
5127 /* If we're already at the start of the function, we've either just
5128 stepped backward into a single instruction function without line
5129 number info, or stepped back out of a signal handler to the first
5130 instruction of the function without line number info. Just keep
5131 going, which will single-step back to the caller. */
5132 if (ecs
->stop_func_start
!= stop_pc
)
5134 /* Set a breakpoint at callee's start address.
5135 From there we can step once and be back in the caller. */
5136 struct symtab_and_line sr_sal
;
5139 sr_sal
.pc
= ecs
->stop_func_start
;
5140 sr_sal
.pspace
= get_frame_program_space (frame
);
5141 insert_step_resume_breakpoint_at_sal (gdbarch
,
5142 sr_sal
, null_frame_id
);
5146 /* Set a breakpoint at callee's return address (the address
5147 at which the caller will resume). */
5148 insert_step_resume_breakpoint_at_caller (frame
);
5154 /* Reverse stepping through solib trampolines. */
5156 if (execution_direction
== EXEC_REVERSE
5157 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5159 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5160 || (ecs
->stop_func_start
== 0
5161 && in_solib_dynsym_resolve_code (stop_pc
)))
5163 /* Any solib trampoline code can be handled in reverse
5164 by simply continuing to single-step. We have already
5165 executed the solib function (backwards), and a few
5166 steps will take us back through the trampoline to the
5171 else if (in_solib_dynsym_resolve_code (stop_pc
))
5173 /* Stepped backward into the solib dynsym resolver.
5174 Set a breakpoint at its start and continue, then
5175 one more step will take us out. */
5176 struct symtab_and_line sr_sal
;
5179 sr_sal
.pc
= ecs
->stop_func_start
;
5180 sr_sal
.pspace
= get_frame_program_space (frame
);
5181 insert_step_resume_breakpoint_at_sal (gdbarch
,
5182 sr_sal
, null_frame_id
);
5188 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5190 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5191 the trampoline processing logic, however, there are some trampolines
5192 that have no names, so we should do trampoline handling first. */
5193 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5194 && ecs
->stop_func_name
== NULL
5195 && stop_pc_sal
.line
== 0)
5198 fprintf_unfiltered (gdb_stdlog
,
5199 "infrun: stepped into undebuggable function\n");
5201 /* The inferior just stepped into, or returned to, an
5202 undebuggable function (where there is no debugging information
5203 and no line number corresponding to the address where the
5204 inferior stopped). Since we want to skip this kind of code,
5205 we keep going until the inferior returns from this
5206 function - unless the user has asked us not to (via
5207 set step-mode) or we no longer know how to get back
5208 to the call site. */
5209 if (step_stop_if_no_debug
5210 || !frame_id_p (frame_unwind_caller_id (frame
)))
5212 /* If we have no line number and the step-stop-if-no-debug
5213 is set, we stop the step so that the user has a chance to
5214 switch in assembly mode. */
5215 end_stepping_range (ecs
);
5220 /* Set a breakpoint at callee's return address (the address
5221 at which the caller will resume). */
5222 insert_step_resume_breakpoint_at_caller (frame
);
5228 if (ecs
->event_thread
->control
.step_range_end
== 1)
5230 /* It is stepi or nexti. We always want to stop stepping after
5233 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5234 end_stepping_range (ecs
);
5238 if (stop_pc_sal
.line
== 0)
5240 /* We have no line number information. That means to stop
5241 stepping (does this always happen right after one instruction,
5242 when we do "s" in a function with no line numbers,
5243 or can this happen as a result of a return or longjmp?). */
5245 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5246 end_stepping_range (ecs
);
5250 /* Look for "calls" to inlined functions, part one. If the inline
5251 frame machinery detected some skipped call sites, we have entered
5252 a new inline function. */
5254 if (frame_id_eq (get_frame_id (get_current_frame ()),
5255 ecs
->event_thread
->control
.step_frame_id
)
5256 && inline_skipped_frames (ecs
->ptid
))
5258 struct symtab_and_line call_sal
;
5261 fprintf_unfiltered (gdb_stdlog
,
5262 "infrun: stepped into inlined function\n");
5264 find_frame_sal (get_current_frame (), &call_sal
);
5266 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5268 /* For "step", we're going to stop. But if the call site
5269 for this inlined function is on the same source line as
5270 we were previously stepping, go down into the function
5271 first. Otherwise stop at the call site. */
5273 if (call_sal
.line
== ecs
->event_thread
->current_line
5274 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5275 step_into_inline_frame (ecs
->ptid
);
5277 end_stepping_range (ecs
);
5282 /* For "next", we should stop at the call site if it is on a
5283 different source line. Otherwise continue through the
5284 inlined function. */
5285 if (call_sal
.line
== ecs
->event_thread
->current_line
5286 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5289 end_stepping_range (ecs
);
5294 /* Look for "calls" to inlined functions, part two. If we are still
5295 in the same real function we were stepping through, but we have
5296 to go further up to find the exact frame ID, we are stepping
5297 through a more inlined call beyond its call site. */
5299 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5300 && !frame_id_eq (get_frame_id (get_current_frame ()),
5301 ecs
->event_thread
->control
.step_frame_id
)
5302 && stepped_in_from (get_current_frame (),
5303 ecs
->event_thread
->control
.step_frame_id
))
5306 fprintf_unfiltered (gdb_stdlog
,
5307 "infrun: stepping through inlined function\n");
5309 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5312 end_stepping_range (ecs
);
5316 if ((stop_pc
== stop_pc_sal
.pc
)
5317 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5318 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5320 /* We are at the start of a different line. So stop. Note that
5321 we don't stop if we step into the middle of a different line.
5322 That is said to make things like for (;;) statements work
5325 fprintf_unfiltered (gdb_stdlog
,
5326 "infrun: stepped to a different line\n");
5327 end_stepping_range (ecs
);
5331 /* We aren't done stepping.
5333 Optimize by setting the stepping range to the line.
5334 (We might not be in the original line, but if we entered a
5335 new line in mid-statement, we continue stepping. This makes
5336 things like for(;;) statements work better.) */
5338 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5339 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5340 ecs
->event_thread
->control
.may_range_step
= 1;
5341 set_step_info (frame
, stop_pc_sal
);
5344 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5348 /* In all-stop mode, if we're currently stepping but have stopped in
5349 some other thread, we may need to switch back to the stepped
5350 thread. Returns true we set the inferior running, false if we left
5351 it stopped (and the event needs further processing). */
5354 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
5358 struct thread_info
*tp
;
5359 struct thread_info
*stepping_thread
;
5360 struct thread_info
*step_over
;
5362 /* If any thread is blocked on some internal breakpoint, and we
5363 simply need to step over that breakpoint to get it going
5364 again, do that first. */
5366 /* However, if we see an event for the stepping thread, then we
5367 know all other threads have been moved past their breakpoints
5368 already. Let the caller check whether the step is finished,
5369 etc., before deciding to move it past a breakpoint. */
5370 if (ecs
->event_thread
->control
.step_range_end
!= 0)
5373 /* Check if the current thread is blocked on an incomplete
5374 step-over, interrupted by a random signal. */
5375 if (ecs
->event_thread
->control
.trap_expected
5376 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5380 fprintf_unfiltered (gdb_stdlog
,
5381 "infrun: need to finish step-over of [%s]\n",
5382 target_pid_to_str (ecs
->event_thread
->ptid
));
5388 /* Check if the current thread is blocked by a single-step
5389 breakpoint of another thread. */
5390 if (ecs
->hit_singlestep_breakpoint
)
5394 fprintf_unfiltered (gdb_stdlog
,
5395 "infrun: need to step [%s] over single-step "
5397 target_pid_to_str (ecs
->ptid
));
5403 /* Otherwise, we no longer expect a trap in the current thread.
5404 Clear the trap_expected flag before switching back -- this is
5405 what keep_going does as well, if we call it. */
5406 ecs
->event_thread
->control
.trap_expected
= 0;
5408 /* Likewise, clear the signal if it should not be passed. */
5409 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5410 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5412 /* If scheduler locking applies even if not stepping, there's no
5413 need to walk over threads. Above we've checked whether the
5414 current thread is stepping. If some other thread not the
5415 event thread is stepping, then it must be that scheduler
5416 locking is not in effect. */
5417 if (schedlock_applies (0))
5420 /* Look for the stepping/nexting thread, and check if any other
5421 thread other than the stepping thread needs to start a
5422 step-over. Do all step-overs before actually proceeding with
5424 stepping_thread
= NULL
;
5426 ALL_NON_EXITED_THREADS (tp
)
5428 /* Ignore threads of processes we're not resuming. */
5430 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (inferior_ptid
))
5433 /* When stepping over a breakpoint, we lock all threads
5434 except the one that needs to move past the breakpoint.
5435 If a non-event thread has this set, the "incomplete
5436 step-over" check above should have caught it earlier. */
5437 gdb_assert (!tp
->control
.trap_expected
);
5439 /* Did we find the stepping thread? */
5440 if (tp
->control
.step_range_end
)
5442 /* Yep. There should only one though. */
5443 gdb_assert (stepping_thread
== NULL
);
5445 /* The event thread is handled at the top, before we
5447 gdb_assert (tp
!= ecs
->event_thread
);
5449 /* If some thread other than the event thread is
5450 stepping, then scheduler locking can't be in effect,
5451 otherwise we wouldn't have resumed the current event
5452 thread in the first place. */
5453 gdb_assert (!schedlock_applies (currently_stepping (tp
)));
5455 stepping_thread
= tp
;
5457 else if (thread_still_needs_step_over (tp
))
5461 /* At the top we've returned early if the event thread
5462 is stepping. If some other thread not the event
5463 thread is stepping, then scheduler locking can't be
5464 in effect, and we can resume this thread. No need to
5465 keep looking for the stepping thread then. */
5470 if (step_over
!= NULL
)
5475 fprintf_unfiltered (gdb_stdlog
,
5476 "infrun: need to step-over [%s]\n",
5477 target_pid_to_str (tp
->ptid
));
5480 /* Only the stepping thread should have this set. */
5481 gdb_assert (tp
->control
.step_range_end
== 0);
5483 ecs
->ptid
= tp
->ptid
;
5484 ecs
->event_thread
= tp
;
5485 switch_to_thread (ecs
->ptid
);
5490 if (stepping_thread
!= NULL
)
5492 struct frame_info
*frame
;
5493 struct gdbarch
*gdbarch
;
5495 tp
= stepping_thread
;
5497 /* If the stepping thread exited, then don't try to switch
5498 back and resume it, which could fail in several different
5499 ways depending on the target. Instead, just keep going.
5501 We can find a stepping dead thread in the thread list in
5504 - The target supports thread exit events, and when the
5505 target tries to delete the thread from the thread list,
5506 inferior_ptid pointed at the exiting thread. In such
5507 case, calling delete_thread does not really remove the
5508 thread from the list; instead, the thread is left listed,
5509 with 'exited' state.
5511 - The target's debug interface does not support thread
5512 exit events, and so we have no idea whatsoever if the
5513 previously stepping thread is still alive. For that
5514 reason, we need to synchronously query the target
5516 if (is_exited (tp
->ptid
)
5517 || !target_thread_alive (tp
->ptid
))
5520 fprintf_unfiltered (gdb_stdlog
,
5521 "infrun: not switching back to "
5522 "stepped thread, it has vanished\n");
5524 delete_thread (tp
->ptid
);
5530 fprintf_unfiltered (gdb_stdlog
,
5531 "infrun: switching back to stepped thread\n");
5533 ecs
->event_thread
= tp
;
5534 ecs
->ptid
= tp
->ptid
;
5535 context_switch (ecs
->ptid
);
5537 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5538 frame
= get_current_frame ();
5539 gdbarch
= get_frame_arch (frame
);
5541 /* If the PC of the thread we were trying to single-step has
5542 changed, then that thread has trapped or been signaled,
5543 but the event has not been reported to GDB yet. Re-poll
5544 the target looking for this particular thread's event
5545 (i.e. temporarily enable schedlock) by:
5547 - setting a break at the current PC
5548 - resuming that particular thread, only (by setting
5551 This prevents us continuously moving the single-step
5552 breakpoint forward, one instruction at a time,
5555 if (gdbarch_software_single_step_p (gdbarch
)
5556 && stop_pc
!= tp
->prev_pc
)
5559 fprintf_unfiltered (gdb_stdlog
,
5560 "infrun: expected thread advanced also\n");
5562 /* Clear the info of the previous step-over, as it's no
5563 longer valid. It's what keep_going would do too, if
5564 we called it. Must do this before trying to insert
5565 the sss breakpoint, otherwise if we were previously
5566 trying to step over this exact address in another
5567 thread, the breakpoint ends up not installed. */
5568 clear_step_over_info ();
5570 insert_single_step_breakpoint (get_frame_arch (frame
),
5571 get_frame_address_space (frame
),
5573 ecs
->event_thread
->control
.trap_expected
= 1;
5575 resume (0, GDB_SIGNAL_0
);
5576 prepare_to_wait (ecs
);
5581 fprintf_unfiltered (gdb_stdlog
,
5582 "infrun: expected thread still "
5583 "hasn't advanced\n");
5593 /* Is thread TP in the middle of single-stepping? */
5596 currently_stepping (struct thread_info
*tp
)
5598 return ((tp
->control
.step_range_end
5599 && tp
->control
.step_resume_breakpoint
== NULL
)
5600 || tp
->control
.trap_expected
5601 || bpstat_should_step ());
5604 /* Inferior has stepped into a subroutine call with source code that
5605 we should not step over. Do step to the first line of code in
5609 handle_step_into_function (struct gdbarch
*gdbarch
,
5610 struct execution_control_state
*ecs
)
5613 struct symtab_and_line stop_func_sal
, sr_sal
;
5615 fill_in_stop_func (gdbarch
, ecs
);
5617 s
= find_pc_symtab (stop_pc
);
5618 if (s
&& s
->language
!= language_asm
)
5619 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5620 ecs
->stop_func_start
);
5622 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5623 /* Use the step_resume_break to step until the end of the prologue,
5624 even if that involves jumps (as it seems to on the vax under
5626 /* If the prologue ends in the middle of a source line, continue to
5627 the end of that source line (if it is still within the function).
5628 Otherwise, just go to end of prologue. */
5629 if (stop_func_sal
.end
5630 && stop_func_sal
.pc
!= ecs
->stop_func_start
5631 && stop_func_sal
.end
< ecs
->stop_func_end
)
5632 ecs
->stop_func_start
= stop_func_sal
.end
;
5634 /* Architectures which require breakpoint adjustment might not be able
5635 to place a breakpoint at the computed address. If so, the test
5636 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5637 ecs->stop_func_start to an address at which a breakpoint may be
5638 legitimately placed.
5640 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5641 made, GDB will enter an infinite loop when stepping through
5642 optimized code consisting of VLIW instructions which contain
5643 subinstructions corresponding to different source lines. On
5644 FR-V, it's not permitted to place a breakpoint on any but the
5645 first subinstruction of a VLIW instruction. When a breakpoint is
5646 set, GDB will adjust the breakpoint address to the beginning of
5647 the VLIW instruction. Thus, we need to make the corresponding
5648 adjustment here when computing the stop address. */
5650 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5652 ecs
->stop_func_start
5653 = gdbarch_adjust_breakpoint_address (gdbarch
,
5654 ecs
->stop_func_start
);
5657 if (ecs
->stop_func_start
== stop_pc
)
5659 /* We are already there: stop now. */
5660 end_stepping_range (ecs
);
5665 /* Put the step-breakpoint there and go until there. */
5666 init_sal (&sr_sal
); /* initialize to zeroes */
5667 sr_sal
.pc
= ecs
->stop_func_start
;
5668 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5669 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5671 /* Do not specify what the fp should be when we stop since on
5672 some machines the prologue is where the new fp value is
5674 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5676 /* And make sure stepping stops right away then. */
5677 ecs
->event_thread
->control
.step_range_end
5678 = ecs
->event_thread
->control
.step_range_start
;
5683 /* Inferior has stepped backward into a subroutine call with source
5684 code that we should not step over. Do step to the beginning of the
5685 last line of code in it. */
5688 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5689 struct execution_control_state
*ecs
)
5692 struct symtab_and_line stop_func_sal
;
5694 fill_in_stop_func (gdbarch
, ecs
);
5696 s
= find_pc_symtab (stop_pc
);
5697 if (s
&& s
->language
!= language_asm
)
5698 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5699 ecs
->stop_func_start
);
5701 stop_func_sal
= find_pc_line (stop_pc
, 0);
5703 /* OK, we're just going to keep stepping here. */
5704 if (stop_func_sal
.pc
== stop_pc
)
5706 /* We're there already. Just stop stepping now. */
5707 end_stepping_range (ecs
);
5711 /* Else just reset the step range and keep going.
5712 No step-resume breakpoint, they don't work for
5713 epilogues, which can have multiple entry paths. */
5714 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5715 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5721 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5722 This is used to both functions and to skip over code. */
5725 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5726 struct symtab_and_line sr_sal
,
5727 struct frame_id sr_id
,
5728 enum bptype sr_type
)
5730 /* There should never be more than one step-resume or longjmp-resume
5731 breakpoint per thread, so we should never be setting a new
5732 step_resume_breakpoint when one is already active. */
5733 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5734 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5737 fprintf_unfiltered (gdb_stdlog
,
5738 "infrun: inserting step-resume breakpoint at %s\n",
5739 paddress (gdbarch
, sr_sal
.pc
));
5741 inferior_thread ()->control
.step_resume_breakpoint
5742 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5746 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5747 struct symtab_and_line sr_sal
,
5748 struct frame_id sr_id
)
5750 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5755 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5756 This is used to skip a potential signal handler.
5758 This is called with the interrupted function's frame. The signal
5759 handler, when it returns, will resume the interrupted function at
5763 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5765 struct symtab_and_line sr_sal
;
5766 struct gdbarch
*gdbarch
;
5768 gdb_assert (return_frame
!= NULL
);
5769 init_sal (&sr_sal
); /* initialize to zeros */
5771 gdbarch
= get_frame_arch (return_frame
);
5772 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5773 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5774 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5776 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5777 get_stack_frame_id (return_frame
),
5781 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5782 is used to skip a function after stepping into it (for "next" or if
5783 the called function has no debugging information).
5785 The current function has almost always been reached by single
5786 stepping a call or return instruction. NEXT_FRAME belongs to the
5787 current function, and the breakpoint will be set at the caller's
5790 This is a separate function rather than reusing
5791 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5792 get_prev_frame, which may stop prematurely (see the implementation
5793 of frame_unwind_caller_id for an example). */
5796 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5798 struct symtab_and_line sr_sal
;
5799 struct gdbarch
*gdbarch
;
5801 /* We shouldn't have gotten here if we don't know where the call site
5803 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5805 init_sal (&sr_sal
); /* initialize to zeros */
5807 gdbarch
= frame_unwind_caller_arch (next_frame
);
5808 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5809 frame_unwind_caller_pc (next_frame
));
5810 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5811 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5813 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5814 frame_unwind_caller_id (next_frame
));
5817 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5818 new breakpoint at the target of a jmp_buf. The handling of
5819 longjmp-resume uses the same mechanisms used for handling
5820 "step-resume" breakpoints. */
5823 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5825 /* There should never be more than one longjmp-resume breakpoint per
5826 thread, so we should never be setting a new
5827 longjmp_resume_breakpoint when one is already active. */
5828 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
5831 fprintf_unfiltered (gdb_stdlog
,
5832 "infrun: inserting longjmp-resume breakpoint at %s\n",
5833 paddress (gdbarch
, pc
));
5835 inferior_thread ()->control
.exception_resume_breakpoint
=
5836 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5839 /* Insert an exception resume breakpoint. TP is the thread throwing
5840 the exception. The block B is the block of the unwinder debug hook
5841 function. FRAME is the frame corresponding to the call to this
5842 function. SYM is the symbol of the function argument holding the
5843 target PC of the exception. */
5846 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5847 const struct block
*b
,
5848 struct frame_info
*frame
,
5851 volatile struct gdb_exception e
;
5853 /* We want to ignore errors here. */
5854 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5856 struct symbol
*vsym
;
5857 struct value
*value
;
5859 struct breakpoint
*bp
;
5861 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5862 value
= read_var_value (vsym
, frame
);
5863 /* If the value was optimized out, revert to the old behavior. */
5864 if (! value_optimized_out (value
))
5866 handler
= value_as_address (value
);
5869 fprintf_unfiltered (gdb_stdlog
,
5870 "infrun: exception resume at %lx\n",
5871 (unsigned long) handler
);
5873 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5874 handler
, bp_exception_resume
);
5876 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5879 bp
->thread
= tp
->num
;
5880 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5885 /* A helper for check_exception_resume that sets an
5886 exception-breakpoint based on a SystemTap probe. */
5889 insert_exception_resume_from_probe (struct thread_info
*tp
,
5890 const struct bound_probe
*probe
,
5891 struct frame_info
*frame
)
5893 struct value
*arg_value
;
5895 struct breakpoint
*bp
;
5897 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
5901 handler
= value_as_address (arg_value
);
5904 fprintf_unfiltered (gdb_stdlog
,
5905 "infrun: exception resume at %s\n",
5906 paddress (get_objfile_arch (probe
->objfile
),
5909 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5910 handler
, bp_exception_resume
);
5911 bp
->thread
= tp
->num
;
5912 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5915 /* This is called when an exception has been intercepted. Check to
5916 see whether the exception's destination is of interest, and if so,
5917 set an exception resume breakpoint there. */
5920 check_exception_resume (struct execution_control_state
*ecs
,
5921 struct frame_info
*frame
)
5923 volatile struct gdb_exception e
;
5924 struct bound_probe probe
;
5925 struct symbol
*func
;
5927 /* First see if this exception unwinding breakpoint was set via a
5928 SystemTap probe point. If so, the probe has two arguments: the
5929 CFA and the HANDLER. We ignore the CFA, extract the handler, and
5930 set a breakpoint there. */
5931 probe
= find_probe_by_pc (get_frame_pc (frame
));
5934 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
5938 func
= get_frame_function (frame
);
5942 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5944 const struct block
*b
;
5945 struct block_iterator iter
;
5949 /* The exception breakpoint is a thread-specific breakpoint on
5950 the unwinder's debug hook, declared as:
5952 void _Unwind_DebugHook (void *cfa, void *handler);
5954 The CFA argument indicates the frame to which control is
5955 about to be transferred. HANDLER is the destination PC.
5957 We ignore the CFA and set a temporary breakpoint at HANDLER.
5958 This is not extremely efficient but it avoids issues in gdb
5959 with computing the DWARF CFA, and it also works even in weird
5960 cases such as throwing an exception from inside a signal
5963 b
= SYMBOL_BLOCK_VALUE (func
);
5964 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
5966 if (!SYMBOL_IS_ARGUMENT (sym
))
5973 insert_exception_resume_breakpoint (ecs
->event_thread
,
5982 stop_waiting (struct execution_control_state
*ecs
)
5985 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
5987 clear_step_over_info ();
5989 /* Let callers know we don't want to wait for the inferior anymore. */
5990 ecs
->wait_some_more
= 0;
5993 /* Called when we should continue running the inferior, because the
5994 current event doesn't cause a user visible stop. This does the
5995 resuming part; waiting for the next event is done elsewhere. */
5998 keep_going (struct execution_control_state
*ecs
)
6000 /* Make sure normal_stop is called if we get a QUIT handled before
6002 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
6004 /* Save the pc before execution, to compare with pc after stop. */
6005 ecs
->event_thread
->prev_pc
6006 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
6008 if (ecs
->event_thread
->control
.trap_expected
6009 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6011 /* We haven't yet gotten our trap, and either: intercepted a
6012 non-signal event (e.g., a fork); or took a signal which we
6013 are supposed to pass through to the inferior. Simply
6015 discard_cleanups (old_cleanups
);
6016 resume (currently_stepping (ecs
->event_thread
),
6017 ecs
->event_thread
->suspend
.stop_signal
);
6021 volatile struct gdb_exception e
;
6022 struct regcache
*regcache
= get_current_regcache ();
6026 /* Either the trap was not expected, but we are continuing
6027 anyway (if we got a signal, the user asked it be passed to
6030 We got our expected trap, but decided we should resume from
6033 We're going to run this baby now!
6035 Note that insert_breakpoints won't try to re-insert
6036 already inserted breakpoints. Therefore, we don't
6037 care if breakpoints were already inserted, or not. */
6039 /* If we need to step over a breakpoint, and we're not using
6040 displaced stepping to do so, insert all breakpoints
6041 (watchpoints, etc.) but the one we're stepping over, step one
6042 instruction, and then re-insert the breakpoint when that step
6045 remove_bp
= (ecs
->hit_singlestep_breakpoint
6046 || thread_still_needs_step_over (ecs
->event_thread
));
6047 remove_wps
= (ecs
->event_thread
->stepping_over_watchpoint
6048 && !target_have_steppable_watchpoint
);
6050 if (remove_bp
&& !use_displaced_stepping (get_regcache_arch (regcache
)))
6052 set_step_over_info (get_regcache_aspace (regcache
),
6053 regcache_read_pc (regcache
), remove_wps
);
6055 else if (remove_wps
)
6056 set_step_over_info (NULL
, 0, remove_wps
);
6058 clear_step_over_info ();
6060 /* Stop stepping if inserting breakpoints fails. */
6061 TRY_CATCH (e
, RETURN_MASK_ERROR
)
6063 insert_breakpoints ();
6067 exception_print (gdb_stderr
, e
);
6072 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
6074 /* Do not deliver GDB_SIGNAL_TRAP (except when the user
6075 explicitly specifies that such a signal should be delivered
6076 to the target program). Typically, that would occur when a
6077 user is debugging a target monitor on a simulator: the target
6078 monitor sets a breakpoint; the simulator encounters this
6079 breakpoint and halts the simulation handing control to GDB;
6080 GDB, noting that the stop address doesn't map to any known
6081 breakpoint, returns control back to the simulator; the
6082 simulator then delivers the hardware equivalent of a
6083 GDB_SIGNAL_TRAP to the program being debugged. */
6084 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6085 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6086 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6088 discard_cleanups (old_cleanups
);
6089 resume (currently_stepping (ecs
->event_thread
),
6090 ecs
->event_thread
->suspend
.stop_signal
);
6093 prepare_to_wait (ecs
);
6096 /* This function normally comes after a resume, before
6097 handle_inferior_event exits. It takes care of any last bits of
6098 housekeeping, and sets the all-important wait_some_more flag. */
6101 prepare_to_wait (struct execution_control_state
*ecs
)
6104 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
6106 /* This is the old end of the while loop. Let everybody know we
6107 want to wait for the inferior some more and get called again
6109 ecs
->wait_some_more
= 1;
6112 /* We are done with the step range of a step/next/si/ni command.
6113 Called once for each n of a "step n" operation. */
6116 end_stepping_range (struct execution_control_state
*ecs
)
6118 ecs
->event_thread
->control
.stop_step
= 1;
6122 /* Several print_*_reason functions to print why the inferior has stopped.
6123 We always print something when the inferior exits, or receives a signal.
6124 The rest of the cases are dealt with later on in normal_stop and
6125 print_it_typical. Ideally there should be a call to one of these
6126 print_*_reason functions functions from handle_inferior_event each time
6127 stop_waiting is called.
6129 Note that we don't call these directly, instead we delegate that to
6130 the interpreters, through observers. Interpreters then call these
6131 with whatever uiout is right. */
6134 print_end_stepping_range_reason (struct ui_out
*uiout
)
6136 /* For CLI-like interpreters, print nothing. */
6138 if (ui_out_is_mi_like_p (uiout
))
6140 ui_out_field_string (uiout
, "reason",
6141 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
6146 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
6148 annotate_signalled ();
6149 if (ui_out_is_mi_like_p (uiout
))
6151 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
6152 ui_out_text (uiout
, "\nProgram terminated with signal ");
6153 annotate_signal_name ();
6154 ui_out_field_string (uiout
, "signal-name",
6155 gdb_signal_to_name (siggnal
));
6156 annotate_signal_name_end ();
6157 ui_out_text (uiout
, ", ");
6158 annotate_signal_string ();
6159 ui_out_field_string (uiout
, "signal-meaning",
6160 gdb_signal_to_string (siggnal
));
6161 annotate_signal_string_end ();
6162 ui_out_text (uiout
, ".\n");
6163 ui_out_text (uiout
, "The program no longer exists.\n");
6167 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
6169 struct inferior
*inf
= current_inferior ();
6170 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
6172 annotate_exited (exitstatus
);
6175 if (ui_out_is_mi_like_p (uiout
))
6176 ui_out_field_string (uiout
, "reason",
6177 async_reason_lookup (EXEC_ASYNC_EXITED
));
6178 ui_out_text (uiout
, "[Inferior ");
6179 ui_out_text (uiout
, plongest (inf
->num
));
6180 ui_out_text (uiout
, " (");
6181 ui_out_text (uiout
, pidstr
);
6182 ui_out_text (uiout
, ") exited with code ");
6183 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
6184 ui_out_text (uiout
, "]\n");
6188 if (ui_out_is_mi_like_p (uiout
))
6190 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
6191 ui_out_text (uiout
, "[Inferior ");
6192 ui_out_text (uiout
, plongest (inf
->num
));
6193 ui_out_text (uiout
, " (");
6194 ui_out_text (uiout
, pidstr
);
6195 ui_out_text (uiout
, ") exited normally]\n");
6200 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
6204 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
6206 struct thread_info
*t
= inferior_thread ();
6208 ui_out_text (uiout
, "\n[");
6209 ui_out_field_string (uiout
, "thread-name",
6210 target_pid_to_str (t
->ptid
));
6211 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
6212 ui_out_text (uiout
, " stopped");
6216 ui_out_text (uiout
, "\nProgram received signal ");
6217 annotate_signal_name ();
6218 if (ui_out_is_mi_like_p (uiout
))
6220 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
6221 ui_out_field_string (uiout
, "signal-name",
6222 gdb_signal_to_name (siggnal
));
6223 annotate_signal_name_end ();
6224 ui_out_text (uiout
, ", ");
6225 annotate_signal_string ();
6226 ui_out_field_string (uiout
, "signal-meaning",
6227 gdb_signal_to_string (siggnal
));
6228 annotate_signal_string_end ();
6230 ui_out_text (uiout
, ".\n");
6234 print_no_history_reason (struct ui_out
*uiout
)
6236 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
6239 /* Print current location without a level number, if we have changed
6240 functions or hit a breakpoint. Print source line if we have one.
6241 bpstat_print contains the logic deciding in detail what to print,
6242 based on the event(s) that just occurred. */
6245 print_stop_event (struct target_waitstatus
*ws
)
6249 int do_frame_printing
= 1;
6250 struct thread_info
*tp
= inferior_thread ();
6252 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
6256 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
6257 should) carry around the function and does (or should) use
6258 that when doing a frame comparison. */
6259 if (tp
->control
.stop_step
6260 && frame_id_eq (tp
->control
.step_frame_id
,
6261 get_frame_id (get_current_frame ()))
6262 && step_start_function
== find_pc_function (stop_pc
))
6264 /* Finished step, just print source line. */
6265 source_flag
= SRC_LINE
;
6269 /* Print location and source line. */
6270 source_flag
= SRC_AND_LOC
;
6273 case PRINT_SRC_AND_LOC
:
6274 /* Print location and source line. */
6275 source_flag
= SRC_AND_LOC
;
6277 case PRINT_SRC_ONLY
:
6278 source_flag
= SRC_LINE
;
6281 /* Something bogus. */
6282 source_flag
= SRC_LINE
;
6283 do_frame_printing
= 0;
6286 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6289 /* The behavior of this routine with respect to the source
6291 SRC_LINE: Print only source line
6292 LOCATION: Print only location
6293 SRC_AND_LOC: Print location and source line. */
6294 if (do_frame_printing
)
6295 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
6297 /* Display the auto-display expressions. */
6301 /* Here to return control to GDB when the inferior stops for real.
6302 Print appropriate messages, remove breakpoints, give terminal our modes.
6304 STOP_PRINT_FRAME nonzero means print the executing frame
6305 (pc, function, args, file, line number and line text).
6306 BREAKPOINTS_FAILED nonzero means stop was due to error
6307 attempting to insert breakpoints. */
6312 struct target_waitstatus last
;
6314 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
6316 get_last_target_status (&last_ptid
, &last
);
6318 /* If an exception is thrown from this point on, make sure to
6319 propagate GDB's knowledge of the executing state to the
6320 frontend/user running state. A QUIT is an easy exception to see
6321 here, so do this before any filtered output. */
6323 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
6324 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6325 && last
.kind
!= TARGET_WAITKIND_EXITED
6326 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6327 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
6329 /* As we're presenting a stop, and potentially removing breakpoints,
6330 update the thread list so we can tell whether there are threads
6331 running on the target. With target remote, for example, we can
6332 only learn about new threads when we explicitly update the thread
6333 list. Do this before notifying the interpreters about signal
6334 stops, end of stepping ranges, etc., so that the "new thread"
6335 output is emitted before e.g., "Program received signal FOO",
6336 instead of after. */
6337 update_thread_list ();
6339 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
6340 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
6342 /* As with the notification of thread events, we want to delay
6343 notifying the user that we've switched thread context until
6344 the inferior actually stops.
6346 There's no point in saying anything if the inferior has exited.
6347 Note that SIGNALLED here means "exited with a signal", not
6348 "received a signal".
6350 Also skip saying anything in non-stop mode. In that mode, as we
6351 don't want GDB to switch threads behind the user's back, to avoid
6352 races where the user is typing a command to apply to thread x,
6353 but GDB switches to thread y before the user finishes entering
6354 the command, fetch_inferior_event installs a cleanup to restore
6355 the current thread back to the thread the user had selected right
6356 after this event is handled, so we're not really switching, only
6357 informing of a stop. */
6359 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
6360 && target_has_execution
6361 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6362 && last
.kind
!= TARGET_WAITKIND_EXITED
6363 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6365 target_terminal_ours_for_output ();
6366 printf_filtered (_("[Switching to %s]\n"),
6367 target_pid_to_str (inferior_ptid
));
6368 annotate_thread_changed ();
6369 previous_inferior_ptid
= inferior_ptid
;
6372 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
6374 gdb_assert (sync_execution
|| !target_can_async_p ());
6376 target_terminal_ours_for_output ();
6377 printf_filtered (_("No unwaited-for children left.\n"));
6380 /* Note: this depends on the update_thread_list call above. */
6381 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
6383 if (remove_breakpoints ())
6385 target_terminal_ours_for_output ();
6386 printf_filtered (_("Cannot remove breakpoints because "
6387 "program is no longer writable.\nFurther "
6388 "execution is probably impossible.\n"));
6392 /* If an auto-display called a function and that got a signal,
6393 delete that auto-display to avoid an infinite recursion. */
6395 if (stopped_by_random_signal
)
6396 disable_current_display ();
6398 /* Notify observers if we finished a "step"-like command, etc. */
6399 if (target_has_execution
6400 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6401 && last
.kind
!= TARGET_WAITKIND_EXITED
6402 && inferior_thread ()->control
.stop_step
)
6404 /* But not if in the middle of doing a "step n" operation for
6406 if (inferior_thread ()->step_multi
)
6409 observer_notify_end_stepping_range ();
6412 target_terminal_ours ();
6413 async_enable_stdin ();
6415 /* Set the current source location. This will also happen if we
6416 display the frame below, but the current SAL will be incorrect
6417 during a user hook-stop function. */
6418 if (has_stack_frames () && !stop_stack_dummy
)
6419 set_current_sal_from_frame (get_current_frame ());
6421 /* Let the user/frontend see the threads as stopped, but do nothing
6422 if the thread was running an infcall. We may be e.g., evaluating
6423 a breakpoint condition. In that case, the thread had state
6424 THREAD_RUNNING before the infcall, and shall remain set to
6425 running, all without informing the user/frontend about state
6426 transition changes. If this is actually a call command, then the
6427 thread was originally already stopped, so there's no state to
6429 if (target_has_execution
&& inferior_thread ()->control
.in_infcall
)
6430 discard_cleanups (old_chain
);
6432 do_cleanups (old_chain
);
6434 /* Look up the hook_stop and run it (CLI internally handles problem
6435 of stop_command's pre-hook not existing). */
6437 catch_errors (hook_stop_stub
, stop_command
,
6438 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
6440 if (!has_stack_frames ())
6443 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
6444 || last
.kind
== TARGET_WAITKIND_EXITED
)
6447 /* Select innermost stack frame - i.e., current frame is frame 0,
6448 and current location is based on that.
6449 Don't do this on return from a stack dummy routine,
6450 or if the program has exited. */
6452 if (!stop_stack_dummy
)
6454 select_frame (get_current_frame ());
6456 /* If --batch-silent is enabled then there's no need to print the current
6457 source location, and to try risks causing an error message about
6458 missing source files. */
6459 if (stop_print_frame
&& !batch_silent
)
6460 print_stop_event (&last
);
6463 /* Save the function value return registers, if we care.
6464 We might be about to restore their previous contents. */
6465 if (inferior_thread ()->control
.proceed_to_finish
6466 && execution_direction
!= EXEC_REVERSE
)
6468 /* This should not be necessary. */
6470 regcache_xfree (stop_registers
);
6472 /* NB: The copy goes through to the target picking up the value of
6473 all the registers. */
6474 stop_registers
= regcache_dup (get_current_regcache ());
6477 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6479 /* Pop the empty frame that contains the stack dummy.
6480 This also restores inferior state prior to the call
6481 (struct infcall_suspend_state). */
6482 struct frame_info
*frame
= get_current_frame ();
6484 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6486 /* frame_pop() calls reinit_frame_cache as the last thing it
6487 does which means there's currently no selected frame. We
6488 don't need to re-establish a selected frame if the dummy call
6489 returns normally, that will be done by
6490 restore_infcall_control_state. However, we do have to handle
6491 the case where the dummy call is returning after being
6492 stopped (e.g. the dummy call previously hit a breakpoint).
6493 We can't know which case we have so just always re-establish
6494 a selected frame here. */
6495 select_frame (get_current_frame ());
6499 annotate_stopped ();
6501 /* Suppress the stop observer if we're in the middle of:
6503 - a step n (n > 1), as there still more steps to be done.
6505 - a "finish" command, as the observer will be called in
6506 finish_command_continuation, so it can include the inferior
6507 function's return value.
6509 - calling an inferior function, as we pretend we inferior didn't
6510 run at all. The return value of the call is handled by the
6511 expression evaluator, through call_function_by_hand. */
6513 if (!target_has_execution
6514 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6515 || last
.kind
== TARGET_WAITKIND_EXITED
6516 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6517 || (!(inferior_thread ()->step_multi
6518 && inferior_thread ()->control
.stop_step
)
6519 && !(inferior_thread ()->control
.stop_bpstat
6520 && inferior_thread ()->control
.proceed_to_finish
)
6521 && !inferior_thread ()->control
.in_infcall
))
6523 if (!ptid_equal (inferior_ptid
, null_ptid
))
6524 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6527 observer_notify_normal_stop (NULL
, stop_print_frame
);
6530 if (target_has_execution
)
6532 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6533 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6534 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6535 Delete any breakpoint that is to be deleted at the next stop. */
6536 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6539 /* Try to get rid of automatically added inferiors that are no
6540 longer needed. Keeping those around slows down things linearly.
6541 Note that this never removes the current inferior. */
6546 hook_stop_stub (void *cmd
)
6548 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6553 signal_stop_state (int signo
)
6555 return signal_stop
[signo
];
6559 signal_print_state (int signo
)
6561 return signal_print
[signo
];
6565 signal_pass_state (int signo
)
6567 return signal_program
[signo
];
6571 signal_cache_update (int signo
)
6575 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6576 signal_cache_update (signo
);
6581 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6582 && signal_print
[signo
] == 0
6583 && signal_program
[signo
] == 1
6584 && signal_catch
[signo
] == 0);
6588 signal_stop_update (int signo
, int state
)
6590 int ret
= signal_stop
[signo
];
6592 signal_stop
[signo
] = state
;
6593 signal_cache_update (signo
);
6598 signal_print_update (int signo
, int state
)
6600 int ret
= signal_print
[signo
];
6602 signal_print
[signo
] = state
;
6603 signal_cache_update (signo
);
6608 signal_pass_update (int signo
, int state
)
6610 int ret
= signal_program
[signo
];
6612 signal_program
[signo
] = state
;
6613 signal_cache_update (signo
);
6617 /* Update the global 'signal_catch' from INFO and notify the
6621 signal_catch_update (const unsigned int *info
)
6625 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
6626 signal_catch
[i
] = info
[i
] > 0;
6627 signal_cache_update (-1);
6628 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6632 sig_print_header (void)
6634 printf_filtered (_("Signal Stop\tPrint\tPass "
6635 "to program\tDescription\n"));
6639 sig_print_info (enum gdb_signal oursig
)
6641 const char *name
= gdb_signal_to_name (oursig
);
6642 int name_padding
= 13 - strlen (name
);
6644 if (name_padding
<= 0)
6647 printf_filtered ("%s", name
);
6648 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6649 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6650 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6651 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6652 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6655 /* Specify how various signals in the inferior should be handled. */
6658 handle_command (char *args
, int from_tty
)
6661 int digits
, wordlen
;
6662 int sigfirst
, signum
, siglast
;
6663 enum gdb_signal oursig
;
6666 unsigned char *sigs
;
6667 struct cleanup
*old_chain
;
6671 error_no_arg (_("signal to handle"));
6674 /* Allocate and zero an array of flags for which signals to handle. */
6676 nsigs
= (int) GDB_SIGNAL_LAST
;
6677 sigs
= (unsigned char *) alloca (nsigs
);
6678 memset (sigs
, 0, nsigs
);
6680 /* Break the command line up into args. */
6682 argv
= gdb_buildargv (args
);
6683 old_chain
= make_cleanup_freeargv (argv
);
6685 /* Walk through the args, looking for signal oursigs, signal names, and
6686 actions. Signal numbers and signal names may be interspersed with
6687 actions, with the actions being performed for all signals cumulatively
6688 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6690 while (*argv
!= NULL
)
6692 wordlen
= strlen (*argv
);
6693 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6697 sigfirst
= siglast
= -1;
6699 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6701 /* Apply action to all signals except those used by the
6702 debugger. Silently skip those. */
6705 siglast
= nsigs
- 1;
6707 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6709 SET_SIGS (nsigs
, sigs
, signal_stop
);
6710 SET_SIGS (nsigs
, sigs
, signal_print
);
6712 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6714 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6716 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6718 SET_SIGS (nsigs
, sigs
, signal_print
);
6720 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6722 SET_SIGS (nsigs
, sigs
, signal_program
);
6724 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6726 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6728 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6730 SET_SIGS (nsigs
, sigs
, signal_program
);
6732 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6734 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6735 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6737 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6739 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6741 else if (digits
> 0)
6743 /* It is numeric. The numeric signal refers to our own
6744 internal signal numbering from target.h, not to host/target
6745 signal number. This is a feature; users really should be
6746 using symbolic names anyway, and the common ones like
6747 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6749 sigfirst
= siglast
= (int)
6750 gdb_signal_from_command (atoi (*argv
));
6751 if ((*argv
)[digits
] == '-')
6754 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6756 if (sigfirst
> siglast
)
6758 /* Bet he didn't figure we'd think of this case... */
6766 oursig
= gdb_signal_from_name (*argv
);
6767 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
6769 sigfirst
= siglast
= (int) oursig
;
6773 /* Not a number and not a recognized flag word => complain. */
6774 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6778 /* If any signal numbers or symbol names were found, set flags for
6779 which signals to apply actions to. */
6781 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6783 switch ((enum gdb_signal
) signum
)
6785 case GDB_SIGNAL_TRAP
:
6786 case GDB_SIGNAL_INT
:
6787 if (!allsigs
&& !sigs
[signum
])
6789 if (query (_("%s is used by the debugger.\n\
6790 Are you sure you want to change it? "),
6791 gdb_signal_to_name ((enum gdb_signal
) signum
)))
6797 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6798 gdb_flush (gdb_stdout
);
6803 case GDB_SIGNAL_DEFAULT
:
6804 case GDB_SIGNAL_UNKNOWN
:
6805 /* Make sure that "all" doesn't print these. */
6816 for (signum
= 0; signum
< nsigs
; signum
++)
6819 signal_cache_update (-1);
6820 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6821 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
6825 /* Show the results. */
6826 sig_print_header ();
6827 for (; signum
< nsigs
; signum
++)
6829 sig_print_info (signum
);
6835 do_cleanups (old_chain
);
6838 /* Complete the "handle" command. */
6840 static VEC (char_ptr
) *
6841 handle_completer (struct cmd_list_element
*ignore
,
6842 const char *text
, const char *word
)
6844 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
6845 static const char * const keywords
[] =
6859 vec_signals
= signal_completer (ignore
, text
, word
);
6860 vec_keywords
= complete_on_enum (keywords
, word
, word
);
6862 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
6863 VEC_free (char_ptr
, vec_signals
);
6864 VEC_free (char_ptr
, vec_keywords
);
6869 xdb_handle_command (char *args
, int from_tty
)
6872 struct cleanup
*old_chain
;
6875 error_no_arg (_("xdb command"));
6877 /* Break the command line up into args. */
6879 argv
= gdb_buildargv (args
);
6880 old_chain
= make_cleanup_freeargv (argv
);
6881 if (argv
[1] != (char *) NULL
)
6886 bufLen
= strlen (argv
[0]) + 20;
6887 argBuf
= (char *) xmalloc (bufLen
);
6891 enum gdb_signal oursig
;
6893 oursig
= gdb_signal_from_name (argv
[0]);
6894 memset (argBuf
, 0, bufLen
);
6895 if (strcmp (argv
[1], "Q") == 0)
6896 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6899 if (strcmp (argv
[1], "s") == 0)
6901 if (!signal_stop
[oursig
])
6902 sprintf (argBuf
, "%s %s", argv
[0], "stop");
6904 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
6906 else if (strcmp (argv
[1], "i") == 0)
6908 if (!signal_program
[oursig
])
6909 sprintf (argBuf
, "%s %s", argv
[0], "pass");
6911 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
6913 else if (strcmp (argv
[1], "r") == 0)
6915 if (!signal_print
[oursig
])
6916 sprintf (argBuf
, "%s %s", argv
[0], "print");
6918 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6924 handle_command (argBuf
, from_tty
);
6926 printf_filtered (_("Invalid signal handling flag.\n"));
6931 do_cleanups (old_chain
);
6935 gdb_signal_from_command (int num
)
6937 if (num
>= 1 && num
<= 15)
6938 return (enum gdb_signal
) num
;
6939 error (_("Only signals 1-15 are valid as numeric signals.\n\
6940 Use \"info signals\" for a list of symbolic signals."));
6943 /* Print current contents of the tables set by the handle command.
6944 It is possible we should just be printing signals actually used
6945 by the current target (but for things to work right when switching
6946 targets, all signals should be in the signal tables). */
6949 signals_info (char *signum_exp
, int from_tty
)
6951 enum gdb_signal oursig
;
6953 sig_print_header ();
6957 /* First see if this is a symbol name. */
6958 oursig
= gdb_signal_from_name (signum_exp
);
6959 if (oursig
== GDB_SIGNAL_UNKNOWN
)
6961 /* No, try numeric. */
6963 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
6965 sig_print_info (oursig
);
6969 printf_filtered ("\n");
6970 /* These ugly casts brought to you by the native VAX compiler. */
6971 for (oursig
= GDB_SIGNAL_FIRST
;
6972 (int) oursig
< (int) GDB_SIGNAL_LAST
;
6973 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
6977 if (oursig
!= GDB_SIGNAL_UNKNOWN
6978 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
6979 sig_print_info (oursig
);
6982 printf_filtered (_("\nUse the \"handle\" command "
6983 "to change these tables.\n"));
6986 /* Check if it makes sense to read $_siginfo from the current thread
6987 at this point. If not, throw an error. */
6990 validate_siginfo_access (void)
6992 /* No current inferior, no siginfo. */
6993 if (ptid_equal (inferior_ptid
, null_ptid
))
6994 error (_("No thread selected."));
6996 /* Don't try to read from a dead thread. */
6997 if (is_exited (inferior_ptid
))
6998 error (_("The current thread has terminated"));
7000 /* ... or from a spinning thread. */
7001 if (is_running (inferior_ptid
))
7002 error (_("Selected thread is running."));
7005 /* The $_siginfo convenience variable is a bit special. We don't know
7006 for sure the type of the value until we actually have a chance to
7007 fetch the data. The type can change depending on gdbarch, so it is
7008 also dependent on which thread you have selected.
7010 1. making $_siginfo be an internalvar that creates a new value on
7013 2. making the value of $_siginfo be an lval_computed value. */
7015 /* This function implements the lval_computed support for reading a
7019 siginfo_value_read (struct value
*v
)
7021 LONGEST transferred
;
7023 validate_siginfo_access ();
7026 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
7028 value_contents_all_raw (v
),
7030 TYPE_LENGTH (value_type (v
)));
7032 if (transferred
!= TYPE_LENGTH (value_type (v
)))
7033 error (_("Unable to read siginfo"));
7036 /* This function implements the lval_computed support for writing a
7040 siginfo_value_write (struct value
*v
, struct value
*fromval
)
7042 LONGEST transferred
;
7044 validate_siginfo_access ();
7046 transferred
= target_write (¤t_target
,
7047 TARGET_OBJECT_SIGNAL_INFO
,
7049 value_contents_all_raw (fromval
),
7051 TYPE_LENGTH (value_type (fromval
)));
7053 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
7054 error (_("Unable to write siginfo"));
7057 static const struct lval_funcs siginfo_value_funcs
=
7063 /* Return a new value with the correct type for the siginfo object of
7064 the current thread using architecture GDBARCH. Return a void value
7065 if there's no object available. */
7067 static struct value
*
7068 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
7071 if (target_has_stack
7072 && !ptid_equal (inferior_ptid
, null_ptid
)
7073 && gdbarch_get_siginfo_type_p (gdbarch
))
7075 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7077 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
7080 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
7084 /* infcall_suspend_state contains state about the program itself like its
7085 registers and any signal it received when it last stopped.
7086 This state must be restored regardless of how the inferior function call
7087 ends (either successfully, or after it hits a breakpoint or signal)
7088 if the program is to properly continue where it left off. */
7090 struct infcall_suspend_state
7092 struct thread_suspend_state thread_suspend
;
7093 #if 0 /* Currently unused and empty structures are not valid C. */
7094 struct inferior_suspend_state inferior_suspend
;
7099 struct regcache
*registers
;
7101 /* Format of SIGINFO_DATA or NULL if it is not present. */
7102 struct gdbarch
*siginfo_gdbarch
;
7104 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
7105 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
7106 content would be invalid. */
7107 gdb_byte
*siginfo_data
;
7110 struct infcall_suspend_state
*
7111 save_infcall_suspend_state (void)
7113 struct infcall_suspend_state
*inf_state
;
7114 struct thread_info
*tp
= inferior_thread ();
7116 struct inferior
*inf
= current_inferior ();
7118 struct regcache
*regcache
= get_current_regcache ();
7119 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7120 gdb_byte
*siginfo_data
= NULL
;
7122 if (gdbarch_get_siginfo_type_p (gdbarch
))
7124 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7125 size_t len
= TYPE_LENGTH (type
);
7126 struct cleanup
*back_to
;
7128 siginfo_data
= xmalloc (len
);
7129 back_to
= make_cleanup (xfree
, siginfo_data
);
7131 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
7132 siginfo_data
, 0, len
) == len
)
7133 discard_cleanups (back_to
);
7136 /* Errors ignored. */
7137 do_cleanups (back_to
);
7138 siginfo_data
= NULL
;
7142 inf_state
= XCNEW (struct infcall_suspend_state
);
7146 inf_state
->siginfo_gdbarch
= gdbarch
;
7147 inf_state
->siginfo_data
= siginfo_data
;
7150 inf_state
->thread_suspend
= tp
->suspend
;
7151 #if 0 /* Currently unused and empty structures are not valid C. */
7152 inf_state
->inferior_suspend
= inf
->suspend
;
7155 /* run_inferior_call will not use the signal due to its `proceed' call with
7156 GDB_SIGNAL_0 anyway. */
7157 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7159 inf_state
->stop_pc
= stop_pc
;
7161 inf_state
->registers
= regcache_dup (regcache
);
7166 /* Restore inferior session state to INF_STATE. */
7169 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
7171 struct thread_info
*tp
= inferior_thread ();
7173 struct inferior
*inf
= current_inferior ();
7175 struct regcache
*regcache
= get_current_regcache ();
7176 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7178 tp
->suspend
= inf_state
->thread_suspend
;
7179 #if 0 /* Currently unused and empty structures are not valid C. */
7180 inf
->suspend
= inf_state
->inferior_suspend
;
7183 stop_pc
= inf_state
->stop_pc
;
7185 if (inf_state
->siginfo_gdbarch
== gdbarch
)
7187 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7189 /* Errors ignored. */
7190 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
7191 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
7194 /* The inferior can be gone if the user types "print exit(0)"
7195 (and perhaps other times). */
7196 if (target_has_execution
)
7197 /* NB: The register write goes through to the target. */
7198 regcache_cpy (regcache
, inf_state
->registers
);
7200 discard_infcall_suspend_state (inf_state
);
7204 do_restore_infcall_suspend_state_cleanup (void *state
)
7206 restore_infcall_suspend_state (state
);
7210 make_cleanup_restore_infcall_suspend_state
7211 (struct infcall_suspend_state
*inf_state
)
7213 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
7217 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
7219 regcache_xfree (inf_state
->registers
);
7220 xfree (inf_state
->siginfo_data
);
7225 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
7227 return inf_state
->registers
;
7230 /* infcall_control_state contains state regarding gdb's control of the
7231 inferior itself like stepping control. It also contains session state like
7232 the user's currently selected frame. */
7234 struct infcall_control_state
7236 struct thread_control_state thread_control
;
7237 struct inferior_control_state inferior_control
;
7240 enum stop_stack_kind stop_stack_dummy
;
7241 int stopped_by_random_signal
;
7242 int stop_after_trap
;
7244 /* ID if the selected frame when the inferior function call was made. */
7245 struct frame_id selected_frame_id
;
7248 /* Save all of the information associated with the inferior<==>gdb
7251 struct infcall_control_state
*
7252 save_infcall_control_state (void)
7254 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
7255 struct thread_info
*tp
= inferior_thread ();
7256 struct inferior
*inf
= current_inferior ();
7258 inf_status
->thread_control
= tp
->control
;
7259 inf_status
->inferior_control
= inf
->control
;
7261 tp
->control
.step_resume_breakpoint
= NULL
;
7262 tp
->control
.exception_resume_breakpoint
= NULL
;
7264 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
7265 chain. If caller's caller is walking the chain, they'll be happier if we
7266 hand them back the original chain when restore_infcall_control_state is
7268 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
7271 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
7272 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
7273 inf_status
->stop_after_trap
= stop_after_trap
;
7275 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
7281 restore_selected_frame (void *args
)
7283 struct frame_id
*fid
= (struct frame_id
*) args
;
7284 struct frame_info
*frame
;
7286 frame
= frame_find_by_id (*fid
);
7288 /* If inf_status->selected_frame_id is NULL, there was no previously
7292 warning (_("Unable to restore previously selected frame."));
7296 select_frame (frame
);
7301 /* Restore inferior session state to INF_STATUS. */
7304 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
7306 struct thread_info
*tp
= inferior_thread ();
7307 struct inferior
*inf
= current_inferior ();
7309 if (tp
->control
.step_resume_breakpoint
)
7310 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
7312 if (tp
->control
.exception_resume_breakpoint
)
7313 tp
->control
.exception_resume_breakpoint
->disposition
7314 = disp_del_at_next_stop
;
7316 /* Handle the bpstat_copy of the chain. */
7317 bpstat_clear (&tp
->control
.stop_bpstat
);
7319 tp
->control
= inf_status
->thread_control
;
7320 inf
->control
= inf_status
->inferior_control
;
7323 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
7324 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
7325 stop_after_trap
= inf_status
->stop_after_trap
;
7327 if (target_has_stack
)
7329 /* The point of catch_errors is that if the stack is clobbered,
7330 walking the stack might encounter a garbage pointer and
7331 error() trying to dereference it. */
7333 (restore_selected_frame
, &inf_status
->selected_frame_id
,
7334 "Unable to restore previously selected frame:\n",
7335 RETURN_MASK_ERROR
) == 0)
7336 /* Error in restoring the selected frame. Select the innermost
7338 select_frame (get_current_frame ());
7345 do_restore_infcall_control_state_cleanup (void *sts
)
7347 restore_infcall_control_state (sts
);
7351 make_cleanup_restore_infcall_control_state
7352 (struct infcall_control_state
*inf_status
)
7354 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
7358 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
7360 if (inf_status
->thread_control
.step_resume_breakpoint
)
7361 inf_status
->thread_control
.step_resume_breakpoint
->disposition
7362 = disp_del_at_next_stop
;
7364 if (inf_status
->thread_control
.exception_resume_breakpoint
)
7365 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
7366 = disp_del_at_next_stop
;
7368 /* See save_infcall_control_state for info on stop_bpstat. */
7369 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
7374 /* restore_inferior_ptid() will be used by the cleanup machinery
7375 to restore the inferior_ptid value saved in a call to
7376 save_inferior_ptid(). */
7379 restore_inferior_ptid (void *arg
)
7381 ptid_t
*saved_ptid_ptr
= arg
;
7383 inferior_ptid
= *saved_ptid_ptr
;
7387 /* Save the value of inferior_ptid so that it may be restored by a
7388 later call to do_cleanups(). Returns the struct cleanup pointer
7389 needed for later doing the cleanup. */
7392 save_inferior_ptid (void)
7394 ptid_t
*saved_ptid_ptr
;
7396 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
7397 *saved_ptid_ptr
= inferior_ptid
;
7398 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
7404 clear_exit_convenience_vars (void)
7406 clear_internalvar (lookup_internalvar ("_exitsignal"));
7407 clear_internalvar (lookup_internalvar ("_exitcode"));
7411 /* User interface for reverse debugging:
7412 Set exec-direction / show exec-direction commands
7413 (returns error unless target implements to_set_exec_direction method). */
7415 int execution_direction
= EXEC_FORWARD
;
7416 static const char exec_forward
[] = "forward";
7417 static const char exec_reverse
[] = "reverse";
7418 static const char *exec_direction
= exec_forward
;
7419 static const char *const exec_direction_names
[] = {
7426 set_exec_direction_func (char *args
, int from_tty
,
7427 struct cmd_list_element
*cmd
)
7429 if (target_can_execute_reverse
)
7431 if (!strcmp (exec_direction
, exec_forward
))
7432 execution_direction
= EXEC_FORWARD
;
7433 else if (!strcmp (exec_direction
, exec_reverse
))
7434 execution_direction
= EXEC_REVERSE
;
7438 exec_direction
= exec_forward
;
7439 error (_("Target does not support this operation."));
7444 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7445 struct cmd_list_element
*cmd
, const char *value
)
7447 switch (execution_direction
) {
7449 fprintf_filtered (out
, _("Forward.\n"));
7452 fprintf_filtered (out
, _("Reverse.\n"));
7455 internal_error (__FILE__
, __LINE__
,
7456 _("bogus execution_direction value: %d"),
7457 (int) execution_direction
);
7462 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7463 struct cmd_list_element
*c
, const char *value
)
7465 fprintf_filtered (file
, _("Resuming the execution of threads "
7466 "of all processes is %s.\n"), value
);
7469 /* Implementation of `siginfo' variable. */
7471 static const struct internalvar_funcs siginfo_funcs
=
7479 _initialize_infrun (void)
7483 struct cmd_list_element
*c
;
7485 add_info ("signals", signals_info
, _("\
7486 What debugger does when program gets various signals.\n\
7487 Specify a signal as argument to print info on that signal only."));
7488 add_info_alias ("handle", "signals", 0);
7490 c
= add_com ("handle", class_run
, handle_command
, _("\
7491 Specify how to handle signals.\n\
7492 Usage: handle SIGNAL [ACTIONS]\n\
7493 Args are signals and actions to apply to those signals.\n\
7494 If no actions are specified, the current settings for the specified signals\n\
7495 will be displayed instead.\n\
7497 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7498 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7499 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7500 The special arg \"all\" is recognized to mean all signals except those\n\
7501 used by the debugger, typically SIGTRAP and SIGINT.\n\
7503 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7504 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7505 Stop means reenter debugger if this signal happens (implies print).\n\
7506 Print means print a message if this signal happens.\n\
7507 Pass means let program see this signal; otherwise program doesn't know.\n\
7508 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7509 Pass and Stop may be combined.\n\
7511 Multiple signals may be specified. Signal numbers and signal names\n\
7512 may be interspersed with actions, with the actions being performed for\n\
7513 all signals cumulatively specified."));
7514 set_cmd_completer (c
, handle_completer
);
7518 add_com ("lz", class_info
, signals_info
, _("\
7519 What debugger does when program gets various signals.\n\
7520 Specify a signal as argument to print info on that signal only."));
7521 add_com ("z", class_run
, xdb_handle_command
, _("\
7522 Specify how to handle a signal.\n\
7523 Args are signals and actions to apply to those signals.\n\
7524 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7525 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7526 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7527 The special arg \"all\" is recognized to mean all signals except those\n\
7528 used by the debugger, typically SIGTRAP and SIGINT.\n\
7529 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7530 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7531 nopass), \"Q\" (noprint)\n\
7532 Stop means reenter debugger if this signal happens (implies print).\n\
7533 Print means print a message if this signal happens.\n\
7534 Pass means let program see this signal; otherwise program doesn't know.\n\
7535 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7536 Pass and Stop may be combined."));
7540 stop_command
= add_cmd ("stop", class_obscure
,
7541 not_just_help_class_command
, _("\
7542 There is no `stop' command, but you can set a hook on `stop'.\n\
7543 This allows you to set a list of commands to be run each time execution\n\
7544 of the program stops."), &cmdlist
);
7546 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7547 Set inferior debugging."), _("\
7548 Show inferior debugging."), _("\
7549 When non-zero, inferior specific debugging is enabled."),
7552 &setdebuglist
, &showdebuglist
);
7554 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7555 &debug_displaced
, _("\
7556 Set displaced stepping debugging."), _("\
7557 Show displaced stepping debugging."), _("\
7558 When non-zero, displaced stepping specific debugging is enabled."),
7560 show_debug_displaced
,
7561 &setdebuglist
, &showdebuglist
);
7563 add_setshow_boolean_cmd ("non-stop", no_class
,
7565 Set whether gdb controls the inferior in non-stop mode."), _("\
7566 Show whether gdb controls the inferior in non-stop mode."), _("\
7567 When debugging a multi-threaded program and this setting is\n\
7568 off (the default, also called all-stop mode), when one thread stops\n\
7569 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7570 all other threads in the program while you interact with the thread of\n\
7571 interest. When you continue or step a thread, you can allow the other\n\
7572 threads to run, or have them remain stopped, but while you inspect any\n\
7573 thread's state, all threads stop.\n\
7575 In non-stop mode, when one thread stops, other threads can continue\n\
7576 to run freely. You'll be able to step each thread independently,\n\
7577 leave it stopped or free to run as needed."),
7583 numsigs
= (int) GDB_SIGNAL_LAST
;
7584 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7585 signal_print
= (unsigned char *)
7586 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7587 signal_program
= (unsigned char *)
7588 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7589 signal_catch
= (unsigned char *)
7590 xmalloc (sizeof (signal_catch
[0]) * numsigs
);
7591 signal_pass
= (unsigned char *)
7592 xmalloc (sizeof (signal_pass
[0]) * numsigs
);
7593 for (i
= 0; i
< numsigs
; i
++)
7596 signal_print
[i
] = 1;
7597 signal_program
[i
] = 1;
7598 signal_catch
[i
] = 0;
7601 /* Signals caused by debugger's own actions
7602 should not be given to the program afterwards. */
7603 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7604 signal_program
[GDB_SIGNAL_INT
] = 0;
7606 /* Signals that are not errors should not normally enter the debugger. */
7607 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7608 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7609 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7610 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7611 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7612 signal_print
[GDB_SIGNAL_PROF
] = 0;
7613 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7614 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7615 signal_stop
[GDB_SIGNAL_IO
] = 0;
7616 signal_print
[GDB_SIGNAL_IO
] = 0;
7617 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7618 signal_print
[GDB_SIGNAL_POLL
] = 0;
7619 signal_stop
[GDB_SIGNAL_URG
] = 0;
7620 signal_print
[GDB_SIGNAL_URG
] = 0;
7621 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7622 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7623 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7624 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7626 /* These signals are used internally by user-level thread
7627 implementations. (See signal(5) on Solaris.) Like the above
7628 signals, a healthy program receives and handles them as part of
7629 its normal operation. */
7630 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7631 signal_print
[GDB_SIGNAL_LWP
] = 0;
7632 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7633 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7634 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7635 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7637 /* Update cached state. */
7638 signal_cache_update (-1);
7640 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7641 &stop_on_solib_events
, _("\
7642 Set stopping for shared library events."), _("\
7643 Show stopping for shared library events."), _("\
7644 If nonzero, gdb will give control to the user when the dynamic linker\n\
7645 notifies gdb of shared library events. The most common event of interest\n\
7646 to the user would be loading/unloading of a new library."),
7647 set_stop_on_solib_events
,
7648 show_stop_on_solib_events
,
7649 &setlist
, &showlist
);
7651 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7652 follow_fork_mode_kind_names
,
7653 &follow_fork_mode_string
, _("\
7654 Set debugger response to a program call of fork or vfork."), _("\
7655 Show debugger response to a program call of fork or vfork."), _("\
7656 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7657 parent - the original process is debugged after a fork\n\
7658 child - the new process is debugged after a fork\n\
7659 The unfollowed process will continue to run.\n\
7660 By default, the debugger will follow the parent process."),
7662 show_follow_fork_mode_string
,
7663 &setlist
, &showlist
);
7665 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7666 follow_exec_mode_names
,
7667 &follow_exec_mode_string
, _("\
7668 Set debugger response to a program call of exec."), _("\
7669 Show debugger response to a program call of exec."), _("\
7670 An exec call replaces the program image of a process.\n\
7672 follow-exec-mode can be:\n\
7674 new - the debugger creates a new inferior and rebinds the process\n\
7675 to this new inferior. The program the process was running before\n\
7676 the exec call can be restarted afterwards by restarting the original\n\
7679 same - the debugger keeps the process bound to the same inferior.\n\
7680 The new executable image replaces the previous executable loaded in\n\
7681 the inferior. Restarting the inferior after the exec call restarts\n\
7682 the executable the process was running after the exec call.\n\
7684 By default, the debugger will use the same inferior."),
7686 show_follow_exec_mode_string
,
7687 &setlist
, &showlist
);
7689 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7690 scheduler_enums
, &scheduler_mode
, _("\
7691 Set mode for locking scheduler during execution."), _("\
7692 Show mode for locking scheduler during execution."), _("\
7693 off == no locking (threads may preempt at any time)\n\
7694 on == full locking (no thread except the current thread may run)\n\
7695 step == scheduler locked during every single-step operation.\n\
7696 In this mode, no other thread may run during a step command.\n\
7697 Other threads may run while stepping over a function call ('next')."),
7698 set_schedlock_func
, /* traps on target vector */
7699 show_scheduler_mode
,
7700 &setlist
, &showlist
);
7702 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7703 Set mode for resuming threads of all processes."), _("\
7704 Show mode for resuming threads of all processes."), _("\
7705 When on, execution commands (such as 'continue' or 'next') resume all\n\
7706 threads of all processes. When off (which is the default), execution\n\
7707 commands only resume the threads of the current process. The set of\n\
7708 threads that are resumed is further refined by the scheduler-locking\n\
7709 mode (see help set scheduler-locking)."),
7711 show_schedule_multiple
,
7712 &setlist
, &showlist
);
7714 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7715 Set mode of the step operation."), _("\
7716 Show mode of the step operation."), _("\
7717 When set, doing a step over a function without debug line information\n\
7718 will stop at the first instruction of that function. Otherwise, the\n\
7719 function is skipped and the step command stops at a different source line."),
7721 show_step_stop_if_no_debug
,
7722 &setlist
, &showlist
);
7724 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
7725 &can_use_displaced_stepping
, _("\
7726 Set debugger's willingness to use displaced stepping."), _("\
7727 Show debugger's willingness to use displaced stepping."), _("\
7728 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7729 supported by the target architecture. If off, gdb will not use displaced\n\
7730 stepping to step over breakpoints, even if such is supported by the target\n\
7731 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7732 if the target architecture supports it and non-stop mode is active, but will not\n\
7733 use it in all-stop mode (see help set non-stop)."),
7735 show_can_use_displaced_stepping
,
7736 &setlist
, &showlist
);
7738 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7739 &exec_direction
, _("Set direction of execution.\n\
7740 Options are 'forward' or 'reverse'."),
7741 _("Show direction of execution (forward/reverse)."),
7742 _("Tells gdb whether to execute forward or backward."),
7743 set_exec_direction_func
, show_exec_direction_func
,
7744 &setlist
, &showlist
);
7746 /* Set/show detach-on-fork: user-settable mode. */
7748 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7749 Set whether gdb will detach the child of a fork."), _("\
7750 Show whether gdb will detach the child of a fork."), _("\
7751 Tells gdb whether to detach the child of a fork."),
7752 NULL
, NULL
, &setlist
, &showlist
);
7754 /* Set/show disable address space randomization mode. */
7756 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7757 &disable_randomization
, _("\
7758 Set disabling of debuggee's virtual address space randomization."), _("\
7759 Show disabling of debuggee's virtual address space randomization."), _("\
7760 When this mode is on (which is the default), randomization of the virtual\n\
7761 address space is disabled. Standalone programs run with the randomization\n\
7762 enabled by default on some platforms."),
7763 &set_disable_randomization
,
7764 &show_disable_randomization
,
7765 &setlist
, &showlist
);
7767 /* ptid initializations */
7768 inferior_ptid
= null_ptid
;
7769 target_last_wait_ptid
= minus_one_ptid
;
7771 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7772 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7773 observer_attach_thread_exit (infrun_thread_thread_exit
);
7774 observer_attach_inferior_exit (infrun_inferior_exit
);
7776 /* Explicitly create without lookup, since that tries to create a
7777 value with a void typed value, and when we get here, gdbarch
7778 isn't initialized yet. At this point, we're quite sure there
7779 isn't another convenience variable of the same name. */
7780 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7782 add_setshow_boolean_cmd ("observer", no_class
,
7783 &observer_mode_1
, _("\
7784 Set whether gdb controls the inferior in observer mode."), _("\
7785 Show whether gdb controls the inferior in observer mode."), _("\
7786 In observer mode, GDB can get data from the inferior, but not\n\
7787 affect its execution. Registers and memory may not be changed,\n\
7788 breakpoints may not be set, and the program cannot be interrupted\n\