1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2015 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 #include "event-loop.h"
66 /* Prototypes for local functions */
68 static void signals_info (char *, int);
70 static void handle_command (char *, int);
72 static void sig_print_info (enum gdb_signal
);
74 static void sig_print_header (void);
76 static void resume_cleanups (void *);
78 static int hook_stop_stub (void *);
80 static int restore_selected_frame (void *);
82 static int follow_fork (void);
84 static int follow_fork_inferior (int follow_child
, int detach_fork
);
86 static void follow_inferior_reset_breakpoints (void);
88 static void set_schedlock_func (char *args
, int from_tty
,
89 struct cmd_list_element
*c
);
91 static int currently_stepping (struct thread_info
*tp
);
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 static int maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
);
105 /* Asynchronous signal handler registered as event loop source for
106 when we have pending events ready to be passed to the core. */
107 static struct async_event_handler
*infrun_async_inferior_event_token
;
109 /* Stores whether infrun_async was previously enabled or disabled.
110 Starts off as -1, indicating "never enabled/disabled". */
111 static int infrun_is_async
= -1;
116 infrun_async (int enable
)
118 if (infrun_is_async
!= enable
)
120 infrun_is_async
= enable
;
123 fprintf_unfiltered (gdb_stdlog
,
124 "infrun: infrun_async(%d)\n",
128 mark_async_event_handler (infrun_async_inferior_event_token
);
130 clear_async_event_handler (infrun_async_inferior_event_token
);
134 /* When set, stop the 'step' command if we enter a function which has
135 no line number information. The normal behavior is that we step
136 over such function. */
137 int step_stop_if_no_debug
= 0;
139 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
140 struct cmd_list_element
*c
, const char *value
)
142 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
145 /* In asynchronous mode, but simulating synchronous execution. */
147 int sync_execution
= 0;
149 /* proceed and normal_stop use this to notify the user when the
150 inferior stopped in a different thread than it had been running
153 static ptid_t previous_inferior_ptid
;
155 /* If set (default for legacy reasons), when following a fork, GDB
156 will detach from one of the fork branches, child or parent.
157 Exactly which branch is detached depends on 'set follow-fork-mode'
160 static int detach_fork
= 1;
162 int debug_displaced
= 0;
164 show_debug_displaced (struct ui_file
*file
, int from_tty
,
165 struct cmd_list_element
*c
, const char *value
)
167 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
170 unsigned int debug_infrun
= 0;
172 show_debug_infrun (struct ui_file
*file
, int from_tty
,
173 struct cmd_list_element
*c
, const char *value
)
175 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
179 /* Support for disabling address space randomization. */
181 int disable_randomization
= 1;
184 show_disable_randomization (struct ui_file
*file
, int from_tty
,
185 struct cmd_list_element
*c
, const char *value
)
187 if (target_supports_disable_randomization ())
188 fprintf_filtered (file
,
189 _("Disabling randomization of debuggee's "
190 "virtual address space is %s.\n"),
193 fputs_filtered (_("Disabling randomization of debuggee's "
194 "virtual address space is unsupported on\n"
195 "this platform.\n"), file
);
199 set_disable_randomization (char *args
, int from_tty
,
200 struct cmd_list_element
*c
)
202 if (!target_supports_disable_randomization ())
203 error (_("Disabling randomization of debuggee's "
204 "virtual address space is unsupported on\n"
208 /* User interface for non-stop mode. */
211 static int non_stop_1
= 0;
214 set_non_stop (char *args
, int from_tty
,
215 struct cmd_list_element
*c
)
217 if (target_has_execution
)
219 non_stop_1
= non_stop
;
220 error (_("Cannot change this setting while the inferior is running."));
223 non_stop
= non_stop_1
;
227 show_non_stop (struct ui_file
*file
, int from_tty
,
228 struct cmd_list_element
*c
, const char *value
)
230 fprintf_filtered (file
,
231 _("Controlling the inferior in non-stop mode is %s.\n"),
235 /* "Observer mode" is somewhat like a more extreme version of
236 non-stop, in which all GDB operations that might affect the
237 target's execution have been disabled. */
239 int observer_mode
= 0;
240 static int observer_mode_1
= 0;
243 set_observer_mode (char *args
, int from_tty
,
244 struct cmd_list_element
*c
)
246 if (target_has_execution
)
248 observer_mode_1
= observer_mode
;
249 error (_("Cannot change this setting while the inferior is running."));
252 observer_mode
= observer_mode_1
;
254 may_write_registers
= !observer_mode
;
255 may_write_memory
= !observer_mode
;
256 may_insert_breakpoints
= !observer_mode
;
257 may_insert_tracepoints
= !observer_mode
;
258 /* We can insert fast tracepoints in or out of observer mode,
259 but enable them if we're going into this mode. */
261 may_insert_fast_tracepoints
= 1;
262 may_stop
= !observer_mode
;
263 update_target_permissions ();
265 /* Going *into* observer mode we must force non-stop, then
266 going out we leave it that way. */
269 pagination_enabled
= 0;
270 non_stop
= non_stop_1
= 1;
274 printf_filtered (_("Observer mode is now %s.\n"),
275 (observer_mode
? "on" : "off"));
279 show_observer_mode (struct ui_file
*file
, int from_tty
,
280 struct cmd_list_element
*c
, const char *value
)
282 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
285 /* This updates the value of observer mode based on changes in
286 permissions. Note that we are deliberately ignoring the values of
287 may-write-registers and may-write-memory, since the user may have
288 reason to enable these during a session, for instance to turn on a
289 debugging-related global. */
292 update_observer_mode (void)
296 newval
= (!may_insert_breakpoints
297 && !may_insert_tracepoints
298 && may_insert_fast_tracepoints
302 /* Let the user know if things change. */
303 if (newval
!= observer_mode
)
304 printf_filtered (_("Observer mode is now %s.\n"),
305 (newval
? "on" : "off"));
307 observer_mode
= observer_mode_1
= newval
;
310 /* Tables of how to react to signals; the user sets them. */
312 static unsigned char *signal_stop
;
313 static unsigned char *signal_print
;
314 static unsigned char *signal_program
;
316 /* Table of signals that are registered with "catch signal". A
317 non-zero entry indicates that the signal is caught by some "catch
318 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
320 static unsigned char *signal_catch
;
322 /* Table of signals that the target may silently handle.
323 This is automatically determined from the flags above,
324 and simply cached here. */
325 static unsigned char *signal_pass
;
327 #define SET_SIGS(nsigs,sigs,flags) \
329 int signum = (nsigs); \
330 while (signum-- > 0) \
331 if ((sigs)[signum]) \
332 (flags)[signum] = 1; \
335 #define UNSET_SIGS(nsigs,sigs,flags) \
337 int signum = (nsigs); \
338 while (signum-- > 0) \
339 if ((sigs)[signum]) \
340 (flags)[signum] = 0; \
343 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
344 this function is to avoid exporting `signal_program'. */
347 update_signals_program_target (void)
349 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
352 /* Value to pass to target_resume() to cause all threads to resume. */
354 #define RESUME_ALL minus_one_ptid
356 /* Command list pointer for the "stop" placeholder. */
358 static struct cmd_list_element
*stop_command
;
360 /* Nonzero if we want to give control to the user when we're notified
361 of shared library events by the dynamic linker. */
362 int stop_on_solib_events
;
364 /* Enable or disable optional shared library event breakpoints
365 as appropriate when the above flag is changed. */
368 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
370 update_solib_breakpoints ();
374 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
375 struct cmd_list_element
*c
, const char *value
)
377 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
381 /* Nonzero means expecting a trace trap
382 and should stop the inferior and return silently when it happens. */
386 /* Nonzero after stop if current stack frame should be printed. */
388 static int stop_print_frame
;
390 /* This is a cached copy of the pid/waitstatus of the last event
391 returned by target_wait()/deprecated_target_wait_hook(). This
392 information is returned by get_last_target_status(). */
393 static ptid_t target_last_wait_ptid
;
394 static struct target_waitstatus target_last_waitstatus
;
396 static void context_switch (ptid_t ptid
);
398 void init_thread_stepping_state (struct thread_info
*tss
);
400 static const char follow_fork_mode_child
[] = "child";
401 static const char follow_fork_mode_parent
[] = "parent";
403 static const char *const follow_fork_mode_kind_names
[] = {
404 follow_fork_mode_child
,
405 follow_fork_mode_parent
,
409 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
411 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
412 struct cmd_list_element
*c
, const char *value
)
414 fprintf_filtered (file
,
415 _("Debugger response to a program "
416 "call of fork or vfork is \"%s\".\n"),
421 /* Handle changes to the inferior list based on the type of fork,
422 which process is being followed, and whether the other process
423 should be detached. On entry inferior_ptid must be the ptid of
424 the fork parent. At return inferior_ptid is the ptid of the
425 followed inferior. */
428 follow_fork_inferior (int follow_child
, int detach_fork
)
431 ptid_t parent_ptid
, child_ptid
;
433 has_vforked
= (inferior_thread ()->pending_follow
.kind
434 == TARGET_WAITKIND_VFORKED
);
435 parent_ptid
= inferior_ptid
;
436 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
439 && !non_stop
/* Non-stop always resumes both branches. */
440 && (!target_is_async_p () || sync_execution
)
441 && !(follow_child
|| detach_fork
|| sched_multi
))
443 /* The parent stays blocked inside the vfork syscall until the
444 child execs or exits. If we don't let the child run, then
445 the parent stays blocked. If we're telling the parent to run
446 in the foreground, the user will not be able to ctrl-c to get
447 back the terminal, effectively hanging the debug session. */
448 fprintf_filtered (gdb_stderr
, _("\
449 Can not resume the parent process over vfork in the foreground while\n\
450 holding the child stopped. Try \"set detach-on-fork\" or \
451 \"set schedule-multiple\".\n"));
452 /* FIXME output string > 80 columns. */
458 /* Detach new forked process? */
461 struct cleanup
*old_chain
;
463 /* Before detaching from the child, remove all breakpoints
464 from it. If we forked, then this has already been taken
465 care of by infrun.c. If we vforked however, any
466 breakpoint inserted in the parent is visible in the
467 child, even those added while stopped in a vfork
468 catchpoint. This will remove the breakpoints from the
469 parent also, but they'll be reinserted below. */
472 /* Keep breakpoints list in sync. */
473 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
476 if (info_verbose
|| debug_infrun
)
478 /* Ensure that we have a process ptid. */
479 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
481 target_terminal_ours_for_output ();
482 fprintf_filtered (gdb_stdlog
,
483 _("Detaching after %s from child %s.\n"),
484 has_vforked
? "vfork" : "fork",
485 target_pid_to_str (process_ptid
));
490 struct inferior
*parent_inf
, *child_inf
;
491 struct cleanup
*old_chain
;
493 /* Add process to GDB's tables. */
494 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
496 parent_inf
= current_inferior ();
497 child_inf
->attach_flag
= parent_inf
->attach_flag
;
498 copy_terminal_info (child_inf
, parent_inf
);
499 child_inf
->gdbarch
= parent_inf
->gdbarch
;
500 copy_inferior_target_desc_info (child_inf
, parent_inf
);
502 old_chain
= save_inferior_ptid ();
503 save_current_program_space ();
505 inferior_ptid
= child_ptid
;
506 add_thread (inferior_ptid
);
507 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
509 /* If this is a vfork child, then the address-space is
510 shared with the parent. */
513 child_inf
->pspace
= parent_inf
->pspace
;
514 child_inf
->aspace
= parent_inf
->aspace
;
516 /* The parent will be frozen until the child is done
517 with the shared region. Keep track of the
519 child_inf
->vfork_parent
= parent_inf
;
520 child_inf
->pending_detach
= 0;
521 parent_inf
->vfork_child
= child_inf
;
522 parent_inf
->pending_detach
= 0;
526 child_inf
->aspace
= new_address_space ();
527 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
528 child_inf
->removable
= 1;
529 set_current_program_space (child_inf
->pspace
);
530 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
532 /* Let the shared library layer (e.g., solib-svr4) learn
533 about this new process, relocate the cloned exec, pull
534 in shared libraries, and install the solib event
535 breakpoint. If a "cloned-VM" event was propagated
536 better throughout the core, this wouldn't be
538 solib_create_inferior_hook (0);
541 do_cleanups (old_chain
);
546 struct inferior
*parent_inf
;
548 parent_inf
= current_inferior ();
550 /* If we detached from the child, then we have to be careful
551 to not insert breakpoints in the parent until the child
552 is done with the shared memory region. However, if we're
553 staying attached to the child, then we can and should
554 insert breakpoints, so that we can debug it. A
555 subsequent child exec or exit is enough to know when does
556 the child stops using the parent's address space. */
557 parent_inf
->waiting_for_vfork_done
= detach_fork
;
558 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
563 /* Follow the child. */
564 struct inferior
*parent_inf
, *child_inf
;
565 struct program_space
*parent_pspace
;
567 if (info_verbose
|| debug_infrun
)
569 target_terminal_ours_for_output ();
570 fprintf_filtered (gdb_stdlog
,
571 _("Attaching after %s %s to child %s.\n"),
572 target_pid_to_str (parent_ptid
),
573 has_vforked
? "vfork" : "fork",
574 target_pid_to_str (child_ptid
));
577 /* Add the new inferior first, so that the target_detach below
578 doesn't unpush the target. */
580 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
582 parent_inf
= current_inferior ();
583 child_inf
->attach_flag
= parent_inf
->attach_flag
;
584 copy_terminal_info (child_inf
, parent_inf
);
585 child_inf
->gdbarch
= parent_inf
->gdbarch
;
586 copy_inferior_target_desc_info (child_inf
, parent_inf
);
588 parent_pspace
= parent_inf
->pspace
;
590 /* If we're vforking, we want to hold on to the parent until the
591 child exits or execs. At child exec or exit time we can
592 remove the old breakpoints from the parent and detach or
593 resume debugging it. Otherwise, detach the parent now; we'll
594 want to reuse it's program/address spaces, but we can't set
595 them to the child before removing breakpoints from the
596 parent, otherwise, the breakpoints module could decide to
597 remove breakpoints from the wrong process (since they'd be
598 assigned to the same address space). */
602 gdb_assert (child_inf
->vfork_parent
== NULL
);
603 gdb_assert (parent_inf
->vfork_child
== NULL
);
604 child_inf
->vfork_parent
= parent_inf
;
605 child_inf
->pending_detach
= 0;
606 parent_inf
->vfork_child
= child_inf
;
607 parent_inf
->pending_detach
= detach_fork
;
608 parent_inf
->waiting_for_vfork_done
= 0;
610 else if (detach_fork
)
612 if (info_verbose
|| debug_infrun
)
614 /* Ensure that we have a process ptid. */
615 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
617 target_terminal_ours_for_output ();
618 fprintf_filtered (gdb_stdlog
,
619 _("Detaching after fork from "
621 target_pid_to_str (process_ptid
));
624 target_detach (NULL
, 0);
627 /* Note that the detach above makes PARENT_INF dangling. */
629 /* Add the child thread to the appropriate lists, and switch to
630 this new thread, before cloning the program space, and
631 informing the solib layer about this new process. */
633 inferior_ptid
= child_ptid
;
634 add_thread (inferior_ptid
);
636 /* If this is a vfork child, then the address-space is shared
637 with the parent. If we detached from the parent, then we can
638 reuse the parent's program/address spaces. */
639 if (has_vforked
|| detach_fork
)
641 child_inf
->pspace
= parent_pspace
;
642 child_inf
->aspace
= child_inf
->pspace
->aspace
;
646 child_inf
->aspace
= new_address_space ();
647 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
648 child_inf
->removable
= 1;
649 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
650 set_current_program_space (child_inf
->pspace
);
651 clone_program_space (child_inf
->pspace
, parent_pspace
);
653 /* Let the shared library layer (e.g., solib-svr4) learn
654 about this new process, relocate the cloned exec, pull in
655 shared libraries, and install the solib event breakpoint.
656 If a "cloned-VM" event was propagated better throughout
657 the core, this wouldn't be required. */
658 solib_create_inferior_hook (0);
662 return target_follow_fork (follow_child
, detach_fork
);
665 /* Tell the target to follow the fork we're stopped at. Returns true
666 if the inferior should be resumed; false, if the target for some
667 reason decided it's best not to resume. */
672 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
673 int should_resume
= 1;
674 struct thread_info
*tp
;
676 /* Copy user stepping state to the new inferior thread. FIXME: the
677 followed fork child thread should have a copy of most of the
678 parent thread structure's run control related fields, not just these.
679 Initialized to avoid "may be used uninitialized" warnings from gcc. */
680 struct breakpoint
*step_resume_breakpoint
= NULL
;
681 struct breakpoint
*exception_resume_breakpoint
= NULL
;
682 CORE_ADDR step_range_start
= 0;
683 CORE_ADDR step_range_end
= 0;
684 struct frame_id step_frame_id
= { 0 };
685 struct interp
*command_interp
= NULL
;
690 struct target_waitstatus wait_status
;
692 /* Get the last target status returned by target_wait(). */
693 get_last_target_status (&wait_ptid
, &wait_status
);
695 /* If not stopped at a fork event, then there's nothing else to
697 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
698 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
701 /* Check if we switched over from WAIT_PTID, since the event was
703 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
704 && !ptid_equal (inferior_ptid
, wait_ptid
))
706 /* We did. Switch back to WAIT_PTID thread, to tell the
707 target to follow it (in either direction). We'll
708 afterwards refuse to resume, and inform the user what
710 switch_to_thread (wait_ptid
);
715 tp
= inferior_thread ();
717 /* If there were any forks/vforks that were caught and are now to be
718 followed, then do so now. */
719 switch (tp
->pending_follow
.kind
)
721 case TARGET_WAITKIND_FORKED
:
722 case TARGET_WAITKIND_VFORKED
:
724 ptid_t parent
, child
;
726 /* If the user did a next/step, etc, over a fork call,
727 preserve the stepping state in the fork child. */
728 if (follow_child
&& should_resume
)
730 step_resume_breakpoint
= clone_momentary_breakpoint
731 (tp
->control
.step_resume_breakpoint
);
732 step_range_start
= tp
->control
.step_range_start
;
733 step_range_end
= tp
->control
.step_range_end
;
734 step_frame_id
= tp
->control
.step_frame_id
;
735 exception_resume_breakpoint
736 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
737 command_interp
= tp
->control
.command_interp
;
739 /* For now, delete the parent's sr breakpoint, otherwise,
740 parent/child sr breakpoints are considered duplicates,
741 and the child version will not be installed. Remove
742 this when the breakpoints module becomes aware of
743 inferiors and address spaces. */
744 delete_step_resume_breakpoint (tp
);
745 tp
->control
.step_range_start
= 0;
746 tp
->control
.step_range_end
= 0;
747 tp
->control
.step_frame_id
= null_frame_id
;
748 delete_exception_resume_breakpoint (tp
);
749 tp
->control
.command_interp
= NULL
;
752 parent
= inferior_ptid
;
753 child
= tp
->pending_follow
.value
.related_pid
;
755 /* Set up inferior(s) as specified by the caller, and tell the
756 target to do whatever is necessary to follow either parent
758 if (follow_fork_inferior (follow_child
, detach_fork
))
760 /* Target refused to follow, or there's some other reason
761 we shouldn't resume. */
766 /* This pending follow fork event is now handled, one way
767 or another. The previous selected thread may be gone
768 from the lists by now, but if it is still around, need
769 to clear the pending follow request. */
770 tp
= find_thread_ptid (parent
);
772 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
774 /* This makes sure we don't try to apply the "Switched
775 over from WAIT_PID" logic above. */
776 nullify_last_target_wait_ptid ();
778 /* If we followed the child, switch to it... */
781 switch_to_thread (child
);
783 /* ... and preserve the stepping state, in case the
784 user was stepping over the fork call. */
787 tp
= inferior_thread ();
788 tp
->control
.step_resume_breakpoint
789 = step_resume_breakpoint
;
790 tp
->control
.step_range_start
= step_range_start
;
791 tp
->control
.step_range_end
= step_range_end
;
792 tp
->control
.step_frame_id
= step_frame_id
;
793 tp
->control
.exception_resume_breakpoint
794 = exception_resume_breakpoint
;
795 tp
->control
.command_interp
= command_interp
;
799 /* If we get here, it was because we're trying to
800 resume from a fork catchpoint, but, the user
801 has switched threads away from the thread that
802 forked. In that case, the resume command
803 issued is most likely not applicable to the
804 child, so just warn, and refuse to resume. */
805 warning (_("Not resuming: switched threads "
806 "before following fork child.\n"));
809 /* Reset breakpoints in the child as appropriate. */
810 follow_inferior_reset_breakpoints ();
813 switch_to_thread (parent
);
817 case TARGET_WAITKIND_SPURIOUS
:
818 /* Nothing to follow. */
821 internal_error (__FILE__
, __LINE__
,
822 "Unexpected pending_follow.kind %d\n",
823 tp
->pending_follow
.kind
);
827 return should_resume
;
831 follow_inferior_reset_breakpoints (void)
833 struct thread_info
*tp
= inferior_thread ();
835 /* Was there a step_resume breakpoint? (There was if the user
836 did a "next" at the fork() call.) If so, explicitly reset its
837 thread number. Cloned step_resume breakpoints are disabled on
838 creation, so enable it here now that it is associated with the
841 step_resumes are a form of bp that are made to be per-thread.
842 Since we created the step_resume bp when the parent process
843 was being debugged, and now are switching to the child process,
844 from the breakpoint package's viewpoint, that's a switch of
845 "threads". We must update the bp's notion of which thread
846 it is for, or it'll be ignored when it triggers. */
848 if (tp
->control
.step_resume_breakpoint
)
850 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
851 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
854 /* Treat exception_resume breakpoints like step_resume breakpoints. */
855 if (tp
->control
.exception_resume_breakpoint
)
857 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
858 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
861 /* Reinsert all breakpoints in the child. The user may have set
862 breakpoints after catching the fork, in which case those
863 were never set in the child, but only in the parent. This makes
864 sure the inserted breakpoints match the breakpoint list. */
866 breakpoint_re_set ();
867 insert_breakpoints ();
870 /* The child has exited or execed: resume threads of the parent the
871 user wanted to be executing. */
874 proceed_after_vfork_done (struct thread_info
*thread
,
877 int pid
= * (int *) arg
;
879 if (ptid_get_pid (thread
->ptid
) == pid
880 && is_running (thread
->ptid
)
881 && !is_executing (thread
->ptid
)
882 && !thread
->stop_requested
883 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
886 fprintf_unfiltered (gdb_stdlog
,
887 "infrun: resuming vfork parent thread %s\n",
888 target_pid_to_str (thread
->ptid
));
890 switch_to_thread (thread
->ptid
);
891 clear_proceed_status (0);
892 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
898 /* Called whenever we notice an exec or exit event, to handle
899 detaching or resuming a vfork parent. */
902 handle_vfork_child_exec_or_exit (int exec
)
904 struct inferior
*inf
= current_inferior ();
906 if (inf
->vfork_parent
)
908 int resume_parent
= -1;
910 /* This exec or exit marks the end of the shared memory region
911 between the parent and the child. If the user wanted to
912 detach from the parent, now is the time. */
914 if (inf
->vfork_parent
->pending_detach
)
916 struct thread_info
*tp
;
917 struct cleanup
*old_chain
;
918 struct program_space
*pspace
;
919 struct address_space
*aspace
;
921 /* follow-fork child, detach-on-fork on. */
923 inf
->vfork_parent
->pending_detach
= 0;
927 /* If we're handling a child exit, then inferior_ptid
928 points at the inferior's pid, not to a thread. */
929 old_chain
= save_inferior_ptid ();
930 save_current_program_space ();
931 save_current_inferior ();
934 old_chain
= save_current_space_and_thread ();
936 /* We're letting loose of the parent. */
937 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
938 switch_to_thread (tp
->ptid
);
940 /* We're about to detach from the parent, which implicitly
941 removes breakpoints from its address space. There's a
942 catch here: we want to reuse the spaces for the child,
943 but, parent/child are still sharing the pspace at this
944 point, although the exec in reality makes the kernel give
945 the child a fresh set of new pages. The problem here is
946 that the breakpoints module being unaware of this, would
947 likely chose the child process to write to the parent
948 address space. Swapping the child temporarily away from
949 the spaces has the desired effect. Yes, this is "sort
952 pspace
= inf
->pspace
;
953 aspace
= inf
->aspace
;
957 if (debug_infrun
|| info_verbose
)
959 target_terminal_ours_for_output ();
963 fprintf_filtered (gdb_stdlog
,
964 _("Detaching vfork parent process "
965 "%d after child exec.\n"),
966 inf
->vfork_parent
->pid
);
970 fprintf_filtered (gdb_stdlog
,
971 _("Detaching vfork parent process "
972 "%d after child exit.\n"),
973 inf
->vfork_parent
->pid
);
977 target_detach (NULL
, 0);
980 inf
->pspace
= pspace
;
981 inf
->aspace
= aspace
;
983 do_cleanups (old_chain
);
987 /* We're staying attached to the parent, so, really give the
988 child a new address space. */
989 inf
->pspace
= add_program_space (maybe_new_address_space ());
990 inf
->aspace
= inf
->pspace
->aspace
;
992 set_current_program_space (inf
->pspace
);
994 resume_parent
= inf
->vfork_parent
->pid
;
996 /* Break the bonds. */
997 inf
->vfork_parent
->vfork_child
= NULL
;
1001 struct cleanup
*old_chain
;
1002 struct program_space
*pspace
;
1004 /* If this is a vfork child exiting, then the pspace and
1005 aspaces were shared with the parent. Since we're
1006 reporting the process exit, we'll be mourning all that is
1007 found in the address space, and switching to null_ptid,
1008 preparing to start a new inferior. But, since we don't
1009 want to clobber the parent's address/program spaces, we
1010 go ahead and create a new one for this exiting
1013 /* Switch to null_ptid, so that clone_program_space doesn't want
1014 to read the selected frame of a dead process. */
1015 old_chain
= save_inferior_ptid ();
1016 inferior_ptid
= null_ptid
;
1018 /* This inferior is dead, so avoid giving the breakpoints
1019 module the option to write through to it (cloning a
1020 program space resets breakpoints). */
1023 pspace
= add_program_space (maybe_new_address_space ());
1024 set_current_program_space (pspace
);
1026 inf
->symfile_flags
= SYMFILE_NO_READ
;
1027 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1028 inf
->pspace
= pspace
;
1029 inf
->aspace
= pspace
->aspace
;
1031 /* Put back inferior_ptid. We'll continue mourning this
1033 do_cleanups (old_chain
);
1035 resume_parent
= inf
->vfork_parent
->pid
;
1036 /* Break the bonds. */
1037 inf
->vfork_parent
->vfork_child
= NULL
;
1040 inf
->vfork_parent
= NULL
;
1042 gdb_assert (current_program_space
== inf
->pspace
);
1044 if (non_stop
&& resume_parent
!= -1)
1046 /* If the user wanted the parent to be running, let it go
1048 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1051 fprintf_unfiltered (gdb_stdlog
,
1052 "infrun: resuming vfork parent process %d\n",
1055 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1057 do_cleanups (old_chain
);
1062 /* Enum strings for "set|show follow-exec-mode". */
1064 static const char follow_exec_mode_new
[] = "new";
1065 static const char follow_exec_mode_same
[] = "same";
1066 static const char *const follow_exec_mode_names
[] =
1068 follow_exec_mode_new
,
1069 follow_exec_mode_same
,
1073 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1075 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1076 struct cmd_list_element
*c
, const char *value
)
1078 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1081 /* EXECD_PATHNAME is assumed to be non-NULL. */
1084 follow_exec (ptid_t ptid
, char *execd_pathname
)
1086 struct thread_info
*th
, *tmp
;
1087 struct inferior
*inf
= current_inferior ();
1088 int pid
= ptid_get_pid (ptid
);
1090 /* This is an exec event that we actually wish to pay attention to.
1091 Refresh our symbol table to the newly exec'd program, remove any
1092 momentary bp's, etc.
1094 If there are breakpoints, they aren't really inserted now,
1095 since the exec() transformed our inferior into a fresh set
1098 We want to preserve symbolic breakpoints on the list, since
1099 we have hopes that they can be reset after the new a.out's
1100 symbol table is read.
1102 However, any "raw" breakpoints must be removed from the list
1103 (e.g., the solib bp's), since their address is probably invalid
1106 And, we DON'T want to call delete_breakpoints() here, since
1107 that may write the bp's "shadow contents" (the instruction
1108 value that was overwritten witha TRAP instruction). Since
1109 we now have a new a.out, those shadow contents aren't valid. */
1111 mark_breakpoints_out ();
1113 /* The target reports the exec event to the main thread, even if
1114 some other thread does the exec, and even if the main thread was
1115 stopped or already gone. We may still have non-leader threads of
1116 the process on our list. E.g., on targets that don't have thread
1117 exit events (like remote); or on native Linux in non-stop mode if
1118 there were only two threads in the inferior and the non-leader
1119 one is the one that execs (and nothing forces an update of the
1120 thread list up to here). When debugging remotely, it's best to
1121 avoid extra traffic, when possible, so avoid syncing the thread
1122 list with the target, and instead go ahead and delete all threads
1123 of the process but one that reported the event. Note this must
1124 be done before calling update_breakpoints_after_exec, as
1125 otherwise clearing the threads' resources would reference stale
1126 thread breakpoints -- it may have been one of these threads that
1127 stepped across the exec. We could just clear their stepping
1128 states, but as long as we're iterating, might as well delete
1129 them. Deleting them now rather than at the next user-visible
1130 stop provides a nicer sequence of events for user and MI
1132 ALL_THREADS_SAFE (th
, tmp
)
1133 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1134 delete_thread (th
->ptid
);
1136 /* We also need to clear any left over stale state for the
1137 leader/event thread. E.g., if there was any step-resume
1138 breakpoint or similar, it's gone now. We cannot truly
1139 step-to-next statement through an exec(). */
1140 th
= inferior_thread ();
1141 th
->control
.step_resume_breakpoint
= NULL
;
1142 th
->control
.exception_resume_breakpoint
= NULL
;
1143 th
->control
.single_step_breakpoints
= NULL
;
1144 th
->control
.step_range_start
= 0;
1145 th
->control
.step_range_end
= 0;
1147 /* The user may have had the main thread held stopped in the
1148 previous image (e.g., schedlock on, or non-stop). Release
1150 th
->stop_requested
= 0;
1152 update_breakpoints_after_exec ();
1154 /* What is this a.out's name? */
1155 printf_unfiltered (_("%s is executing new program: %s\n"),
1156 target_pid_to_str (inferior_ptid
),
1159 /* We've followed the inferior through an exec. Therefore, the
1160 inferior has essentially been killed & reborn. */
1162 gdb_flush (gdb_stdout
);
1164 breakpoint_init_inferior (inf_execd
);
1166 if (*gdb_sysroot
!= '\0')
1168 char *name
= exec_file_find (execd_pathname
, NULL
);
1170 execd_pathname
= alloca (strlen (name
) + 1);
1171 strcpy (execd_pathname
, name
);
1175 /* Reset the shared library package. This ensures that we get a
1176 shlib event when the child reaches "_start", at which point the
1177 dld will have had a chance to initialize the child. */
1178 /* Also, loading a symbol file below may trigger symbol lookups, and
1179 we don't want those to be satisfied by the libraries of the
1180 previous incarnation of this process. */
1181 no_shared_libraries (NULL
, 0);
1183 if (follow_exec_mode_string
== follow_exec_mode_new
)
1185 struct program_space
*pspace
;
1187 /* The user wants to keep the old inferior and program spaces
1188 around. Create a new fresh one, and switch to it. */
1190 inf
= add_inferior (current_inferior ()->pid
);
1191 pspace
= add_program_space (maybe_new_address_space ());
1192 inf
->pspace
= pspace
;
1193 inf
->aspace
= pspace
->aspace
;
1195 exit_inferior_num_silent (current_inferior ()->num
);
1197 set_current_inferior (inf
);
1198 set_current_program_space (pspace
);
1202 /* The old description may no longer be fit for the new image.
1203 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1204 old description; we'll read a new one below. No need to do
1205 this on "follow-exec-mode new", as the old inferior stays
1206 around (its description is later cleared/refetched on
1208 target_clear_description ();
1211 gdb_assert (current_program_space
== inf
->pspace
);
1213 /* That a.out is now the one to use. */
1214 exec_file_attach (execd_pathname
, 0);
1216 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1217 (Position Independent Executable) main symbol file will get applied by
1218 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1219 the breakpoints with the zero displacement. */
1221 symbol_file_add (execd_pathname
,
1223 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
1226 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
1227 set_initial_language ();
1229 /* If the target can specify a description, read it. Must do this
1230 after flipping to the new executable (because the target supplied
1231 description must be compatible with the executable's
1232 architecture, and the old executable may e.g., be 32-bit, while
1233 the new one 64-bit), and before anything involving memory or
1235 target_find_description ();
1237 solib_create_inferior_hook (0);
1239 jit_inferior_created_hook ();
1241 breakpoint_re_set ();
1243 /* Reinsert all breakpoints. (Those which were symbolic have
1244 been reset to the proper address in the new a.out, thanks
1245 to symbol_file_command...). */
1246 insert_breakpoints ();
1248 /* The next resume of this inferior should bring it to the shlib
1249 startup breakpoints. (If the user had also set bp's on
1250 "main" from the old (parent) process, then they'll auto-
1251 matically get reset there in the new process.). */
1254 /* The queue of threads that need to do a step-over operation to get
1255 past e.g., a breakpoint. What technique is used to step over the
1256 breakpoint/watchpoint does not matter -- all threads end up in the
1257 same queue, to maintain rough temporal order of execution, in order
1258 to avoid starvation, otherwise, we could e.g., find ourselves
1259 constantly stepping the same couple threads past their breakpoints
1260 over and over, if the single-step finish fast enough. */
1261 struct thread_info
*step_over_queue_head
;
1263 /* Bit flags indicating what the thread needs to step over. */
1267 /* Step over a breakpoint. */
1268 STEP_OVER_BREAKPOINT
= 1,
1270 /* Step past a non-continuable watchpoint, in order to let the
1271 instruction execute so we can evaluate the watchpoint
1273 STEP_OVER_WATCHPOINT
= 2
1276 /* Info about an instruction that is being stepped over. */
1278 struct step_over_info
1280 /* If we're stepping past a breakpoint, this is the address space
1281 and address of the instruction the breakpoint is set at. We'll
1282 skip inserting all breakpoints here. Valid iff ASPACE is
1284 struct address_space
*aspace
;
1287 /* The instruction being stepped over triggers a nonsteppable
1288 watchpoint. If true, we'll skip inserting watchpoints. */
1289 int nonsteppable_watchpoint_p
;
1292 /* The step-over info of the location that is being stepped over.
1294 Note that with async/breakpoint always-inserted mode, a user might
1295 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1296 being stepped over. As setting a new breakpoint inserts all
1297 breakpoints, we need to make sure the breakpoint being stepped over
1298 isn't inserted then. We do that by only clearing the step-over
1299 info when the step-over is actually finished (or aborted).
1301 Presently GDB can only step over one breakpoint at any given time.
1302 Given threads that can't run code in the same address space as the
1303 breakpoint's can't really miss the breakpoint, GDB could be taught
1304 to step-over at most one breakpoint per address space (so this info
1305 could move to the address space object if/when GDB is extended).
1306 The set of breakpoints being stepped over will normally be much
1307 smaller than the set of all breakpoints, so a flag in the
1308 breakpoint location structure would be wasteful. A separate list
1309 also saves complexity and run-time, as otherwise we'd have to go
1310 through all breakpoint locations clearing their flag whenever we
1311 start a new sequence. Similar considerations weigh against storing
1312 this info in the thread object. Plus, not all step overs actually
1313 have breakpoint locations -- e.g., stepping past a single-step
1314 breakpoint, or stepping to complete a non-continuable
1316 static struct step_over_info step_over_info
;
1318 /* Record the address of the breakpoint/instruction we're currently
1322 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1323 int nonsteppable_watchpoint_p
)
1325 step_over_info
.aspace
= aspace
;
1326 step_over_info
.address
= address
;
1327 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1330 /* Called when we're not longer stepping over a breakpoint / an
1331 instruction, so all breakpoints are free to be (re)inserted. */
1334 clear_step_over_info (void)
1337 fprintf_unfiltered (gdb_stdlog
,
1338 "infrun: clear_step_over_info\n");
1339 step_over_info
.aspace
= NULL
;
1340 step_over_info
.address
= 0;
1341 step_over_info
.nonsteppable_watchpoint_p
= 0;
1347 stepping_past_instruction_at (struct address_space
*aspace
,
1350 return (step_over_info
.aspace
!= NULL
1351 && breakpoint_address_match (aspace
, address
,
1352 step_over_info
.aspace
,
1353 step_over_info
.address
));
1359 stepping_past_nonsteppable_watchpoint (void)
1361 return step_over_info
.nonsteppable_watchpoint_p
;
1364 /* Returns true if step-over info is valid. */
1367 step_over_info_valid_p (void)
1369 return (step_over_info
.aspace
!= NULL
1370 || stepping_past_nonsteppable_watchpoint ());
1374 /* Displaced stepping. */
1376 /* In non-stop debugging mode, we must take special care to manage
1377 breakpoints properly; in particular, the traditional strategy for
1378 stepping a thread past a breakpoint it has hit is unsuitable.
1379 'Displaced stepping' is a tactic for stepping one thread past a
1380 breakpoint it has hit while ensuring that other threads running
1381 concurrently will hit the breakpoint as they should.
1383 The traditional way to step a thread T off a breakpoint in a
1384 multi-threaded program in all-stop mode is as follows:
1386 a0) Initially, all threads are stopped, and breakpoints are not
1388 a1) We single-step T, leaving breakpoints uninserted.
1389 a2) We insert breakpoints, and resume all threads.
1391 In non-stop debugging, however, this strategy is unsuitable: we
1392 don't want to have to stop all threads in the system in order to
1393 continue or step T past a breakpoint. Instead, we use displaced
1396 n0) Initially, T is stopped, other threads are running, and
1397 breakpoints are inserted.
1398 n1) We copy the instruction "under" the breakpoint to a separate
1399 location, outside the main code stream, making any adjustments
1400 to the instruction, register, and memory state as directed by
1402 n2) We single-step T over the instruction at its new location.
1403 n3) We adjust the resulting register and memory state as directed
1404 by T's architecture. This includes resetting T's PC to point
1405 back into the main instruction stream.
1408 This approach depends on the following gdbarch methods:
1410 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1411 indicate where to copy the instruction, and how much space must
1412 be reserved there. We use these in step n1.
1414 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1415 address, and makes any necessary adjustments to the instruction,
1416 register contents, and memory. We use this in step n1.
1418 - gdbarch_displaced_step_fixup adjusts registers and memory after
1419 we have successfuly single-stepped the instruction, to yield the
1420 same effect the instruction would have had if we had executed it
1421 at its original address. We use this in step n3.
1423 - gdbarch_displaced_step_free_closure provides cleanup.
1425 The gdbarch_displaced_step_copy_insn and
1426 gdbarch_displaced_step_fixup functions must be written so that
1427 copying an instruction with gdbarch_displaced_step_copy_insn,
1428 single-stepping across the copied instruction, and then applying
1429 gdbarch_displaced_insn_fixup should have the same effects on the
1430 thread's memory and registers as stepping the instruction in place
1431 would have. Exactly which responsibilities fall to the copy and
1432 which fall to the fixup is up to the author of those functions.
1434 See the comments in gdbarch.sh for details.
1436 Note that displaced stepping and software single-step cannot
1437 currently be used in combination, although with some care I think
1438 they could be made to. Software single-step works by placing
1439 breakpoints on all possible subsequent instructions; if the
1440 displaced instruction is a PC-relative jump, those breakpoints
1441 could fall in very strange places --- on pages that aren't
1442 executable, or at addresses that are not proper instruction
1443 boundaries. (We do generally let other threads run while we wait
1444 to hit the software single-step breakpoint, and they might
1445 encounter such a corrupted instruction.) One way to work around
1446 this would be to have gdbarch_displaced_step_copy_insn fully
1447 simulate the effect of PC-relative instructions (and return NULL)
1448 on architectures that use software single-stepping.
1450 In non-stop mode, we can have independent and simultaneous step
1451 requests, so more than one thread may need to simultaneously step
1452 over a breakpoint. The current implementation assumes there is
1453 only one scratch space per process. In this case, we have to
1454 serialize access to the scratch space. If thread A wants to step
1455 over a breakpoint, but we are currently waiting for some other
1456 thread to complete a displaced step, we leave thread A stopped and
1457 place it in the displaced_step_request_queue. Whenever a displaced
1458 step finishes, we pick the next thread in the queue and start a new
1459 displaced step operation on it. See displaced_step_prepare and
1460 displaced_step_fixup for details. */
1462 /* Per-inferior displaced stepping state. */
1463 struct displaced_step_inferior_state
1465 /* Pointer to next in linked list. */
1466 struct displaced_step_inferior_state
*next
;
1468 /* The process this displaced step state refers to. */
1471 /* If this is not null_ptid, this is the thread carrying out a
1472 displaced single-step in process PID. This thread's state will
1473 require fixing up once it has completed its step. */
1476 /* The architecture the thread had when we stepped it. */
1477 struct gdbarch
*step_gdbarch
;
1479 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1480 for post-step cleanup. */
1481 struct displaced_step_closure
*step_closure
;
1483 /* The address of the original instruction, and the copy we
1485 CORE_ADDR step_original
, step_copy
;
1487 /* Saved contents of copy area. */
1488 gdb_byte
*step_saved_copy
;
1491 /* The list of states of processes involved in displaced stepping
1493 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1495 /* Get the displaced stepping state of process PID. */
1497 static struct displaced_step_inferior_state
*
1498 get_displaced_stepping_state (int pid
)
1500 struct displaced_step_inferior_state
*state
;
1502 for (state
= displaced_step_inferior_states
;
1504 state
= state
->next
)
1505 if (state
->pid
== pid
)
1511 /* Returns true if any inferior has a thread doing a displaced
1515 displaced_step_in_progress_any_inferior (void)
1517 struct displaced_step_inferior_state
*state
;
1519 for (state
= displaced_step_inferior_states
;
1521 state
= state
->next
)
1522 if (!ptid_equal (state
->step_ptid
, null_ptid
))
1528 /* Return true if process PID has a thread doing a displaced step. */
1531 displaced_step_in_progress (int pid
)
1533 struct displaced_step_inferior_state
*displaced
;
1535 displaced
= get_displaced_stepping_state (pid
);
1536 if (displaced
!= NULL
&& !ptid_equal (displaced
->step_ptid
, null_ptid
))
1542 /* Add a new displaced stepping state for process PID to the displaced
1543 stepping state list, or return a pointer to an already existing
1544 entry, if it already exists. Never returns NULL. */
1546 static struct displaced_step_inferior_state
*
1547 add_displaced_stepping_state (int pid
)
1549 struct displaced_step_inferior_state
*state
;
1551 for (state
= displaced_step_inferior_states
;
1553 state
= state
->next
)
1554 if (state
->pid
== pid
)
1557 state
= xcalloc (1, sizeof (*state
));
1559 state
->next
= displaced_step_inferior_states
;
1560 displaced_step_inferior_states
= state
;
1565 /* If inferior is in displaced stepping, and ADDR equals to starting address
1566 of copy area, return corresponding displaced_step_closure. Otherwise,
1569 struct displaced_step_closure
*
1570 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1572 struct displaced_step_inferior_state
*displaced
1573 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1575 /* If checking the mode of displaced instruction in copy area. */
1576 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1577 && (displaced
->step_copy
== addr
))
1578 return displaced
->step_closure
;
1583 /* Remove the displaced stepping state of process PID. */
1586 remove_displaced_stepping_state (int pid
)
1588 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1590 gdb_assert (pid
!= 0);
1592 it
= displaced_step_inferior_states
;
1593 prev_next_p
= &displaced_step_inferior_states
;
1598 *prev_next_p
= it
->next
;
1603 prev_next_p
= &it
->next
;
1609 infrun_inferior_exit (struct inferior
*inf
)
1611 remove_displaced_stepping_state (inf
->pid
);
1614 /* If ON, and the architecture supports it, GDB will use displaced
1615 stepping to step over breakpoints. If OFF, or if the architecture
1616 doesn't support it, GDB will instead use the traditional
1617 hold-and-step approach. If AUTO (which is the default), GDB will
1618 decide which technique to use to step over breakpoints depending on
1619 which of all-stop or non-stop mode is active --- displaced stepping
1620 in non-stop mode; hold-and-step in all-stop mode. */
1622 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1625 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1626 struct cmd_list_element
*c
,
1629 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1630 fprintf_filtered (file
,
1631 _("Debugger's willingness to use displaced stepping "
1632 "to step over breakpoints is %s (currently %s).\n"),
1633 value
, target_is_non_stop_p () ? "on" : "off");
1635 fprintf_filtered (file
,
1636 _("Debugger's willingness to use displaced stepping "
1637 "to step over breakpoints is %s.\n"), value
);
1640 /* Return non-zero if displaced stepping can/should be used to step
1641 over breakpoints. */
1644 use_displaced_stepping (struct gdbarch
*gdbarch
)
1646 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1647 && target_is_non_stop_p ())
1648 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1649 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1650 && find_record_target () == NULL
);
1653 /* Clean out any stray displaced stepping state. */
1655 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1657 /* Indicate that there is no cleanup pending. */
1658 displaced
->step_ptid
= null_ptid
;
1660 if (displaced
->step_closure
)
1662 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1663 displaced
->step_closure
);
1664 displaced
->step_closure
= NULL
;
1669 displaced_step_clear_cleanup (void *arg
)
1671 struct displaced_step_inferior_state
*state
= arg
;
1673 displaced_step_clear (state
);
1676 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1678 displaced_step_dump_bytes (struct ui_file
*file
,
1679 const gdb_byte
*buf
,
1684 for (i
= 0; i
< len
; i
++)
1685 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1686 fputs_unfiltered ("\n", file
);
1689 /* Prepare to single-step, using displaced stepping.
1691 Note that we cannot use displaced stepping when we have a signal to
1692 deliver. If we have a signal to deliver and an instruction to step
1693 over, then after the step, there will be no indication from the
1694 target whether the thread entered a signal handler or ignored the
1695 signal and stepped over the instruction successfully --- both cases
1696 result in a simple SIGTRAP. In the first case we mustn't do a
1697 fixup, and in the second case we must --- but we can't tell which.
1698 Comments in the code for 'random signals' in handle_inferior_event
1699 explain how we handle this case instead.
1701 Returns 1 if preparing was successful -- this thread is going to be
1702 stepped now; or 0 if displaced stepping this thread got queued. */
1704 displaced_step_prepare (ptid_t ptid
)
1706 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1707 struct thread_info
*tp
= find_thread_ptid (ptid
);
1708 struct regcache
*regcache
= get_thread_regcache (ptid
);
1709 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1710 CORE_ADDR original
, copy
;
1712 struct displaced_step_closure
*closure
;
1713 struct displaced_step_inferior_state
*displaced
;
1716 /* We should never reach this function if the architecture does not
1717 support displaced stepping. */
1718 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1720 /* Nor if the thread isn't meant to step over a breakpoint. */
1721 gdb_assert (tp
->control
.trap_expected
);
1723 /* Disable range stepping while executing in the scratch pad. We
1724 want a single-step even if executing the displaced instruction in
1725 the scratch buffer lands within the stepping range (e.g., a
1727 tp
->control
.may_range_step
= 0;
1729 /* We have to displaced step one thread at a time, as we only have
1730 access to a single scratch space per inferior. */
1732 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1734 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1736 /* Already waiting for a displaced step to finish. Defer this
1737 request and place in queue. */
1739 if (debug_displaced
)
1740 fprintf_unfiltered (gdb_stdlog
,
1741 "displaced: deferring step of %s\n",
1742 target_pid_to_str (ptid
));
1744 thread_step_over_chain_enqueue (tp
);
1749 if (debug_displaced
)
1750 fprintf_unfiltered (gdb_stdlog
,
1751 "displaced: stepping %s now\n",
1752 target_pid_to_str (ptid
));
1755 displaced_step_clear (displaced
);
1757 old_cleanups
= save_inferior_ptid ();
1758 inferior_ptid
= ptid
;
1760 original
= regcache_read_pc (regcache
);
1762 copy
= gdbarch_displaced_step_location (gdbarch
);
1763 len
= gdbarch_max_insn_length (gdbarch
);
1765 /* Save the original contents of the copy area. */
1766 displaced
->step_saved_copy
= xmalloc (len
);
1767 ignore_cleanups
= make_cleanup (free_current_contents
,
1768 &displaced
->step_saved_copy
);
1769 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1771 throw_error (MEMORY_ERROR
,
1772 _("Error accessing memory address %s (%s) for "
1773 "displaced-stepping scratch space."),
1774 paddress (gdbarch
, copy
), safe_strerror (status
));
1775 if (debug_displaced
)
1777 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1778 paddress (gdbarch
, copy
));
1779 displaced_step_dump_bytes (gdb_stdlog
,
1780 displaced
->step_saved_copy
,
1784 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1785 original
, copy
, regcache
);
1787 /* We don't support the fully-simulated case at present. */
1788 gdb_assert (closure
);
1790 /* Save the information we need to fix things up if the step
1792 displaced
->step_ptid
= ptid
;
1793 displaced
->step_gdbarch
= gdbarch
;
1794 displaced
->step_closure
= closure
;
1795 displaced
->step_original
= original
;
1796 displaced
->step_copy
= copy
;
1798 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1800 /* Resume execution at the copy. */
1801 regcache_write_pc (regcache
, copy
);
1803 discard_cleanups (ignore_cleanups
);
1805 do_cleanups (old_cleanups
);
1807 if (debug_displaced
)
1808 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1809 paddress (gdbarch
, copy
));
1815 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1816 const gdb_byte
*myaddr
, int len
)
1818 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1820 inferior_ptid
= ptid
;
1821 write_memory (memaddr
, myaddr
, len
);
1822 do_cleanups (ptid_cleanup
);
1825 /* Restore the contents of the copy area for thread PTID. */
1828 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1831 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1833 write_memory_ptid (ptid
, displaced
->step_copy
,
1834 displaced
->step_saved_copy
, len
);
1835 if (debug_displaced
)
1836 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1837 target_pid_to_str (ptid
),
1838 paddress (displaced
->step_gdbarch
,
1839 displaced
->step_copy
));
1842 /* If we displaced stepped an instruction successfully, adjust
1843 registers and memory to yield the same effect the instruction would
1844 have had if we had executed it at its original address, and return
1845 1. If the instruction didn't complete, relocate the PC and return
1846 -1. If the thread wasn't displaced stepping, return 0. */
1849 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1851 struct cleanup
*old_cleanups
;
1852 struct displaced_step_inferior_state
*displaced
1853 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1856 /* Was any thread of this process doing a displaced step? */
1857 if (displaced
== NULL
)
1860 /* Was this event for the pid we displaced? */
1861 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1862 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1865 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1867 displaced_step_restore (displaced
, displaced
->step_ptid
);
1869 /* Fixup may need to read memory/registers. Switch to the thread
1870 that we're fixing up. Also, target_stopped_by_watchpoint checks
1871 the current thread. */
1872 switch_to_thread (event_ptid
);
1874 /* Did the instruction complete successfully? */
1875 if (signal
== GDB_SIGNAL_TRAP
1876 && !(target_stopped_by_watchpoint ()
1877 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
1878 || target_have_steppable_watchpoint
)))
1880 /* Fix up the resulting state. */
1881 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1882 displaced
->step_closure
,
1883 displaced
->step_original
,
1884 displaced
->step_copy
,
1885 get_thread_regcache (displaced
->step_ptid
));
1890 /* Since the instruction didn't complete, all we can do is
1892 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1893 CORE_ADDR pc
= regcache_read_pc (regcache
);
1895 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1896 regcache_write_pc (regcache
, pc
);
1900 do_cleanups (old_cleanups
);
1902 displaced
->step_ptid
= null_ptid
;
1907 /* Data to be passed around while handling an event. This data is
1908 discarded between events. */
1909 struct execution_control_state
1912 /* The thread that got the event, if this was a thread event; NULL
1914 struct thread_info
*event_thread
;
1916 struct target_waitstatus ws
;
1917 int stop_func_filled_in
;
1918 CORE_ADDR stop_func_start
;
1919 CORE_ADDR stop_func_end
;
1920 const char *stop_func_name
;
1923 /* True if the event thread hit the single-step breakpoint of
1924 another thread. Thus the event doesn't cause a stop, the thread
1925 needs to be single-stepped past the single-step breakpoint before
1926 we can switch back to the original stepping thread. */
1927 int hit_singlestep_breakpoint
;
1930 /* Clear ECS and set it to point at TP. */
1933 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
1935 memset (ecs
, 0, sizeof (*ecs
));
1936 ecs
->event_thread
= tp
;
1937 ecs
->ptid
= tp
->ptid
;
1940 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
1941 static void prepare_to_wait (struct execution_control_state
*ecs
);
1942 static int keep_going_stepped_thread (struct thread_info
*tp
);
1943 static int thread_still_needs_step_over (struct thread_info
*tp
);
1945 /* Are there any pending step-over requests? If so, run all we can
1946 now and return true. Otherwise, return false. */
1949 start_step_over (void)
1951 struct thread_info
*tp
, *next
;
1953 /* Don't start a new step-over if we already have an in-line
1954 step-over operation ongoing. */
1955 if (step_over_info_valid_p ())
1958 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
1960 struct execution_control_state ecss
;
1961 struct execution_control_state
*ecs
= &ecss
;
1962 enum step_over_what step_what
;
1963 int must_be_in_line
;
1964 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
1965 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1967 next
= thread_step_over_chain_next (tp
);
1969 /* If this inferior already has a displaced step in process,
1970 don't start a new one. */
1971 if (displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
1974 step_what
= thread_still_needs_step_over (tp
);
1975 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
1976 || ((step_what
& STEP_OVER_BREAKPOINT
)
1977 && !use_displaced_stepping (gdbarch
)));
1979 /* We currently stop all threads of all processes to step-over
1980 in-line. If we need to start a new in-line step-over, let
1981 any pending displaced steps finish first. */
1982 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
1985 thread_step_over_chain_remove (tp
);
1987 if (step_over_queue_head
== NULL
)
1990 fprintf_unfiltered (gdb_stdlog
,
1991 "infrun: step-over queue now empty\n");
1994 if (tp
->control
.trap_expected
1998 internal_error (__FILE__
, __LINE__
,
1999 "[%s] has inconsistent state: "
2000 "trap_expected=%d, resumed=%d, executing=%d\n",
2001 target_pid_to_str (tp
->ptid
),
2002 tp
->control
.trap_expected
,
2008 fprintf_unfiltered (gdb_stdlog
,
2009 "infrun: resuming [%s] for step-over\n",
2010 target_pid_to_str (tp
->ptid
));
2012 /* keep_going_pass_signal skips the step-over if the breakpoint
2013 is no longer inserted. In all-stop, we want to keep looking
2014 for a thread that needs a step-over instead of resuming TP,
2015 because we wouldn't be able to resume anything else until the
2016 target stops again. In non-stop, the resume always resumes
2017 only TP, so it's OK to let the thread resume freely. */
2018 if (!target_is_non_stop_p () && !step_what
)
2021 switch_to_thread (tp
->ptid
);
2022 reset_ecs (ecs
, tp
);
2023 keep_going_pass_signal (ecs
);
2025 if (!ecs
->wait_some_more
)
2026 error (_("Command aborted."));
2028 gdb_assert (tp
->resumed
);
2030 /* If we started a new in-line step-over, we're done. */
2031 if (step_over_info_valid_p ())
2033 gdb_assert (tp
->control
.trap_expected
);
2037 if (!target_is_non_stop_p ())
2039 /* On all-stop, shouldn't have resumed unless we needed a
2041 gdb_assert (tp
->control
.trap_expected
2042 || tp
->step_after_step_resume_breakpoint
);
2044 /* With remote targets (at least), in all-stop, we can't
2045 issue any further remote commands until the program stops
2050 /* Either the thread no longer needed a step-over, or a new
2051 displaced stepping sequence started. Even in the latter
2052 case, continue looking. Maybe we can also start another
2053 displaced step on a thread of other process. */
2059 /* Update global variables holding ptids to hold NEW_PTID if they were
2060 holding OLD_PTID. */
2062 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2064 struct displaced_step_request
*it
;
2065 struct displaced_step_inferior_state
*displaced
;
2067 if (ptid_equal (inferior_ptid
, old_ptid
))
2068 inferior_ptid
= new_ptid
;
2070 for (displaced
= displaced_step_inferior_states
;
2072 displaced
= displaced
->next
)
2074 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
2075 displaced
->step_ptid
= new_ptid
;
2082 /* Things to clean up if we QUIT out of resume (). */
2084 resume_cleanups (void *ignore
)
2086 if (!ptid_equal (inferior_ptid
, null_ptid
))
2087 delete_single_step_breakpoints (inferior_thread ());
2092 static const char schedlock_off
[] = "off";
2093 static const char schedlock_on
[] = "on";
2094 static const char schedlock_step
[] = "step";
2095 static const char *const scheduler_enums
[] = {
2101 static const char *scheduler_mode
= schedlock_off
;
2103 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2104 struct cmd_list_element
*c
, const char *value
)
2106 fprintf_filtered (file
,
2107 _("Mode for locking scheduler "
2108 "during execution is \"%s\".\n"),
2113 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
2115 if (!target_can_lock_scheduler
)
2117 scheduler_mode
= schedlock_off
;
2118 error (_("Target '%s' cannot support this command."), target_shortname
);
2122 /* True if execution commands resume all threads of all processes by
2123 default; otherwise, resume only threads of the current inferior
2125 int sched_multi
= 0;
2127 /* Try to setup for software single stepping over the specified location.
2128 Return 1 if target_resume() should use hardware single step.
2130 GDBARCH the current gdbarch.
2131 PC the location to step over. */
2134 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2138 if (execution_direction
== EXEC_FORWARD
2139 && gdbarch_software_single_step_p (gdbarch
)
2140 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
2150 user_visible_resume_ptid (int step
)
2156 /* With non-stop mode on, threads are always handled
2158 resume_ptid
= inferior_ptid
;
2160 else if ((scheduler_mode
== schedlock_on
)
2161 || (scheduler_mode
== schedlock_step
&& step
))
2163 /* User-settable 'scheduler' mode requires solo thread
2165 resume_ptid
= inferior_ptid
;
2167 else if (!sched_multi
&& target_supports_multi_process ())
2169 /* Resume all threads of the current process (and none of other
2171 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2175 /* Resume all threads of all processes. */
2176 resume_ptid
= RESUME_ALL
;
2182 /* Return a ptid representing the set of threads that we will resume,
2183 in the perspective of the target, assuming run control handling
2184 does not require leaving some threads stopped (e.g., stepping past
2185 breakpoint). USER_STEP indicates whether we're about to start the
2186 target for a stepping command. */
2189 internal_resume_ptid (int user_step
)
2191 /* In non-stop, we always control threads individually. Note that
2192 the target may always work in non-stop mode even with "set
2193 non-stop off", in which case user_visible_resume_ptid could
2194 return a wildcard ptid. */
2195 if (target_is_non_stop_p ())
2196 return inferior_ptid
;
2198 return user_visible_resume_ptid (user_step
);
2201 /* Wrapper for target_resume, that handles infrun-specific
2205 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2207 struct thread_info
*tp
= inferior_thread ();
2209 /* Install inferior's terminal modes. */
2210 target_terminal_inferior ();
2212 /* Avoid confusing the next resume, if the next stop/resume
2213 happens to apply to another thread. */
2214 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2216 /* Advise target which signals may be handled silently.
2218 If we have removed breakpoints because we are stepping over one
2219 in-line (in any thread), we need to receive all signals to avoid
2220 accidentally skipping a breakpoint during execution of a signal
2223 Likewise if we're displaced stepping, otherwise a trap for a
2224 breakpoint in a signal handler might be confused with the
2225 displaced step finishing. We don't make the displaced_step_fixup
2226 step distinguish the cases instead, because:
2228 - a backtrace while stopped in the signal handler would show the
2229 scratch pad as frame older than the signal handler, instead of
2230 the real mainline code.
2232 - when the thread is later resumed, the signal handler would
2233 return to the scratch pad area, which would no longer be
2235 if (step_over_info_valid_p ()
2236 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2237 target_pass_signals (0, NULL
);
2239 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2241 target_resume (resume_ptid
, step
, sig
);
2244 /* Resume the inferior, but allow a QUIT. This is useful if the user
2245 wants to interrupt some lengthy single-stepping operation
2246 (for child processes, the SIGINT goes to the inferior, and so
2247 we get a SIGINT random_signal, but for remote debugging and perhaps
2248 other targets, that's not true).
2250 SIG is the signal to give the inferior (zero for none). */
2252 resume (enum gdb_signal sig
)
2254 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2255 struct regcache
*regcache
= get_current_regcache ();
2256 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2257 struct thread_info
*tp
= inferior_thread ();
2258 CORE_ADDR pc
= regcache_read_pc (regcache
);
2259 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2261 /* This represents the user's step vs continue request. When
2262 deciding whether "set scheduler-locking step" applies, it's the
2263 user's intention that counts. */
2264 const int user_step
= tp
->control
.stepping_command
;
2265 /* This represents what we'll actually request the target to do.
2266 This can decay from a step to a continue, if e.g., we need to
2267 implement single-stepping with breakpoints (software
2271 gdb_assert (!thread_is_in_step_over_chain (tp
));
2275 if (tp
->suspend
.waitstatus_pending_p
)
2281 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2282 fprintf_unfiltered (gdb_stdlog
,
2283 "infrun: resume: thread %s has pending wait status %s "
2284 "(currently_stepping=%d).\n",
2285 target_pid_to_str (tp
->ptid
), statstr
,
2286 currently_stepping (tp
));
2292 /* FIXME: What should we do if we are supposed to resume this
2293 thread with a signal? Maybe we should maintain a queue of
2294 pending signals to deliver. */
2295 if (sig
!= GDB_SIGNAL_0
)
2297 warning (_("Couldn't deliver signal %s to %s.\n"),
2298 gdb_signal_to_name (sig
), target_pid_to_str (tp
->ptid
));
2301 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2302 discard_cleanups (old_cleanups
);
2304 if (target_can_async_p ())
2309 tp
->stepped_breakpoint
= 0;
2311 /* Depends on stepped_breakpoint. */
2312 step
= currently_stepping (tp
);
2314 if (current_inferior ()->waiting_for_vfork_done
)
2316 /* Don't try to single-step a vfork parent that is waiting for
2317 the child to get out of the shared memory region (by exec'ing
2318 or exiting). This is particularly important on software
2319 single-step archs, as the child process would trip on the
2320 software single step breakpoint inserted for the parent
2321 process. Since the parent will not actually execute any
2322 instruction until the child is out of the shared region (such
2323 are vfork's semantics), it is safe to simply continue it.
2324 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2325 the parent, and tell it to `keep_going', which automatically
2326 re-sets it stepping. */
2328 fprintf_unfiltered (gdb_stdlog
,
2329 "infrun: resume : clear step\n");
2334 fprintf_unfiltered (gdb_stdlog
,
2335 "infrun: resume (step=%d, signal=%s), "
2336 "trap_expected=%d, current thread [%s] at %s\n",
2337 step
, gdb_signal_to_symbol_string (sig
),
2338 tp
->control
.trap_expected
,
2339 target_pid_to_str (inferior_ptid
),
2340 paddress (gdbarch
, pc
));
2342 /* Normally, by the time we reach `resume', the breakpoints are either
2343 removed or inserted, as appropriate. The exception is if we're sitting
2344 at a permanent breakpoint; we need to step over it, but permanent
2345 breakpoints can't be removed. So we have to test for it here. */
2346 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2348 if (sig
!= GDB_SIGNAL_0
)
2350 /* We have a signal to pass to the inferior. The resume
2351 may, or may not take us to the signal handler. If this
2352 is a step, we'll need to stop in the signal handler, if
2353 there's one, (if the target supports stepping into
2354 handlers), or in the next mainline instruction, if
2355 there's no handler. If this is a continue, we need to be
2356 sure to run the handler with all breakpoints inserted.
2357 In all cases, set a breakpoint at the current address
2358 (where the handler returns to), and once that breakpoint
2359 is hit, resume skipping the permanent breakpoint. If
2360 that breakpoint isn't hit, then we've stepped into the
2361 signal handler (or hit some other event). We'll delete
2362 the step-resume breakpoint then. */
2365 fprintf_unfiltered (gdb_stdlog
,
2366 "infrun: resume: skipping permanent breakpoint, "
2367 "deliver signal first\n");
2369 clear_step_over_info ();
2370 tp
->control
.trap_expected
= 0;
2372 if (tp
->control
.step_resume_breakpoint
== NULL
)
2374 /* Set a "high-priority" step-resume, as we don't want
2375 user breakpoints at PC to trigger (again) when this
2377 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2378 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2380 tp
->step_after_step_resume_breakpoint
= step
;
2383 insert_breakpoints ();
2387 /* There's no signal to pass, we can go ahead and skip the
2388 permanent breakpoint manually. */
2390 fprintf_unfiltered (gdb_stdlog
,
2391 "infrun: resume: skipping permanent breakpoint\n");
2392 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2393 /* Update pc to reflect the new address from which we will
2394 execute instructions. */
2395 pc
= regcache_read_pc (regcache
);
2399 /* We've already advanced the PC, so the stepping part
2400 is done. Now we need to arrange for a trap to be
2401 reported to handle_inferior_event. Set a breakpoint
2402 at the current PC, and run to it. Don't update
2403 prev_pc, because if we end in
2404 switch_back_to_stepped_thread, we want the "expected
2405 thread advanced also" branch to be taken. IOW, we
2406 don't want this thread to step further from PC
2408 gdb_assert (!step_over_info_valid_p ());
2409 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2410 insert_breakpoints ();
2412 resume_ptid
= internal_resume_ptid (user_step
);
2413 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2414 discard_cleanups (old_cleanups
);
2421 /* If we have a breakpoint to step over, make sure to do a single
2422 step only. Same if we have software watchpoints. */
2423 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2424 tp
->control
.may_range_step
= 0;
2426 /* If enabled, step over breakpoints by executing a copy of the
2427 instruction at a different address.
2429 We can't use displaced stepping when we have a signal to deliver;
2430 the comments for displaced_step_prepare explain why. The
2431 comments in the handle_inferior event for dealing with 'random
2432 signals' explain what we do instead.
2434 We can't use displaced stepping when we are waiting for vfork_done
2435 event, displaced stepping breaks the vfork child similarly as single
2436 step software breakpoint. */
2437 if (use_displaced_stepping (gdbarch
)
2438 && tp
->control
.trap_expected
2439 && !step_over_info_valid_p ()
2440 && sig
== GDB_SIGNAL_0
2441 && !current_inferior ()->waiting_for_vfork_done
)
2443 struct displaced_step_inferior_state
*displaced
;
2445 if (!displaced_step_prepare (inferior_ptid
))
2448 fprintf_unfiltered (gdb_stdlog
,
2449 "Got placed in step-over queue\n");
2451 tp
->control
.trap_expected
= 0;
2452 discard_cleanups (old_cleanups
);
2456 /* Update pc to reflect the new address from which we will execute
2457 instructions due to displaced stepping. */
2458 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2460 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2461 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2462 displaced
->step_closure
);
2465 /* Do we need to do it the hard way, w/temp breakpoints? */
2467 step
= maybe_software_singlestep (gdbarch
, pc
);
2469 /* Currently, our software single-step implementation leads to different
2470 results than hardware single-stepping in one situation: when stepping
2471 into delivering a signal which has an associated signal handler,
2472 hardware single-step will stop at the first instruction of the handler,
2473 while software single-step will simply skip execution of the handler.
2475 For now, this difference in behavior is accepted since there is no
2476 easy way to actually implement single-stepping into a signal handler
2477 without kernel support.
2479 However, there is one scenario where this difference leads to follow-on
2480 problems: if we're stepping off a breakpoint by removing all breakpoints
2481 and then single-stepping. In this case, the software single-step
2482 behavior means that even if there is a *breakpoint* in the signal
2483 handler, GDB still would not stop.
2485 Fortunately, we can at least fix this particular issue. We detect
2486 here the case where we are about to deliver a signal while software
2487 single-stepping with breakpoints removed. In this situation, we
2488 revert the decisions to remove all breakpoints and insert single-
2489 step breakpoints, and instead we install a step-resume breakpoint
2490 at the current address, deliver the signal without stepping, and
2491 once we arrive back at the step-resume breakpoint, actually step
2492 over the breakpoint we originally wanted to step over. */
2493 if (thread_has_single_step_breakpoints_set (tp
)
2494 && sig
!= GDB_SIGNAL_0
2495 && step_over_info_valid_p ())
2497 /* If we have nested signals or a pending signal is delivered
2498 immediately after a handler returns, might might already have
2499 a step-resume breakpoint set on the earlier handler. We cannot
2500 set another step-resume breakpoint; just continue on until the
2501 original breakpoint is hit. */
2502 if (tp
->control
.step_resume_breakpoint
== NULL
)
2504 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2505 tp
->step_after_step_resume_breakpoint
= 1;
2508 delete_single_step_breakpoints (tp
);
2510 clear_step_over_info ();
2511 tp
->control
.trap_expected
= 0;
2513 insert_breakpoints ();
2516 /* If STEP is set, it's a request to use hardware stepping
2517 facilities. But in that case, we should never
2518 use singlestep breakpoint. */
2519 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2521 /* Decide the set of threads to ask the target to resume. */
2522 if ((step
|| thread_has_single_step_breakpoints_set (tp
))
2523 && tp
->control
.trap_expected
)
2525 /* We're allowing a thread to run past a breakpoint it has
2526 hit, by single-stepping the thread with the breakpoint
2527 removed. In which case, we need to single-step only this
2528 thread, and keep others stopped, as they can miss this
2529 breakpoint if allowed to run. */
2530 resume_ptid
= inferior_ptid
;
2533 resume_ptid
= internal_resume_ptid (user_step
);
2535 if (execution_direction
!= EXEC_REVERSE
2536 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2538 /* There are two cases where we currently need to step a
2539 breakpoint instruction when we have a signal to deliver:
2541 - See handle_signal_stop where we handle random signals that
2542 could take out us out of the stepping range. Normally, in
2543 that case we end up continuing (instead of stepping) over the
2544 signal handler with a breakpoint at PC, but there are cases
2545 where we should _always_ single-step, even if we have a
2546 step-resume breakpoint, like when a software watchpoint is
2547 set. Assuming single-stepping and delivering a signal at the
2548 same time would takes us to the signal handler, then we could
2549 have removed the breakpoint at PC to step over it. However,
2550 some hardware step targets (like e.g., Mac OS) can't step
2551 into signal handlers, and for those, we need to leave the
2552 breakpoint at PC inserted, as otherwise if the handler
2553 recurses and executes PC again, it'll miss the breakpoint.
2554 So we leave the breakpoint inserted anyway, but we need to
2555 record that we tried to step a breakpoint instruction, so
2556 that adjust_pc_after_break doesn't end up confused.
2558 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2559 in one thread after another thread that was stepping had been
2560 momentarily paused for a step-over. When we re-resume the
2561 stepping thread, it may be resumed from that address with a
2562 breakpoint that hasn't trapped yet. Seen with
2563 gdb.threads/non-stop-fair-events.exp, on targets that don't
2564 do displaced stepping. */
2567 fprintf_unfiltered (gdb_stdlog
,
2568 "infrun: resume: [%s] stepped breakpoint\n",
2569 target_pid_to_str (tp
->ptid
));
2571 tp
->stepped_breakpoint
= 1;
2573 /* Most targets can step a breakpoint instruction, thus
2574 executing it normally. But if this one cannot, just
2575 continue and we will hit it anyway. */
2576 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2581 && use_displaced_stepping (gdbarch
)
2582 && tp
->control
.trap_expected
2583 && !step_over_info_valid_p ())
2585 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2586 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2587 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2590 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2591 paddress (resume_gdbarch
, actual_pc
));
2592 read_memory (actual_pc
, buf
, sizeof (buf
));
2593 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2596 if (tp
->control
.may_range_step
)
2598 /* If we're resuming a thread with the PC out of the step
2599 range, then we're doing some nested/finer run control
2600 operation, like stepping the thread out of the dynamic
2601 linker or the displaced stepping scratch pad. We
2602 shouldn't have allowed a range step then. */
2603 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2606 do_target_resume (resume_ptid
, step
, sig
);
2608 discard_cleanups (old_cleanups
);
2613 /* Clear out all variables saying what to do when inferior is continued.
2614 First do this, then set the ones you want, then call `proceed'. */
2617 clear_proceed_status_thread (struct thread_info
*tp
)
2620 fprintf_unfiltered (gdb_stdlog
,
2621 "infrun: clear_proceed_status_thread (%s)\n",
2622 target_pid_to_str (tp
->ptid
));
2624 /* If we're starting a new sequence, then the previous finished
2625 single-step is no longer relevant. */
2626 if (tp
->suspend
.waitstatus_pending_p
)
2628 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2631 fprintf_unfiltered (gdb_stdlog
,
2632 "infrun: clear_proceed_status: pending "
2633 "event of %s was a finished step. "
2635 target_pid_to_str (tp
->ptid
));
2637 tp
->suspend
.waitstatus_pending_p
= 0;
2638 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2640 else if (debug_infrun
)
2644 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2645 fprintf_unfiltered (gdb_stdlog
,
2646 "infrun: clear_proceed_status_thread: thread %s "
2647 "has pending wait status %s "
2648 "(currently_stepping=%d).\n",
2649 target_pid_to_str (tp
->ptid
), statstr
,
2650 currently_stepping (tp
));
2655 /* If this signal should not be seen by program, give it zero.
2656 Used for debugging signals. */
2657 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2658 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2660 tp
->control
.trap_expected
= 0;
2661 tp
->control
.step_range_start
= 0;
2662 tp
->control
.step_range_end
= 0;
2663 tp
->control
.may_range_step
= 0;
2664 tp
->control
.step_frame_id
= null_frame_id
;
2665 tp
->control
.step_stack_frame_id
= null_frame_id
;
2666 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2667 tp
->control
.step_start_function
= NULL
;
2668 tp
->stop_requested
= 0;
2670 tp
->control
.stop_step
= 0;
2672 tp
->control
.proceed_to_finish
= 0;
2674 tp
->control
.command_interp
= NULL
;
2675 tp
->control
.stepping_command
= 0;
2677 /* Discard any remaining commands or status from previous stop. */
2678 bpstat_clear (&tp
->control
.stop_bpstat
);
2682 clear_proceed_status (int step
)
2686 struct thread_info
*tp
;
2689 resume_ptid
= user_visible_resume_ptid (step
);
2691 /* In all-stop mode, delete the per-thread status of all threads
2692 we're about to resume, implicitly and explicitly. */
2693 ALL_NON_EXITED_THREADS (tp
)
2695 if (!ptid_match (tp
->ptid
, resume_ptid
))
2697 clear_proceed_status_thread (tp
);
2701 if (!ptid_equal (inferior_ptid
, null_ptid
))
2703 struct inferior
*inferior
;
2707 /* If in non-stop mode, only delete the per-thread status of
2708 the current thread. */
2709 clear_proceed_status_thread (inferior_thread ());
2712 inferior
= current_inferior ();
2713 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2716 stop_after_trap
= 0;
2718 observer_notify_about_to_proceed ();
2721 /* Returns true if TP is still stopped at a breakpoint that needs
2722 stepping-over in order to make progress. If the breakpoint is gone
2723 meanwhile, we can skip the whole step-over dance. */
2726 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2728 if (tp
->stepping_over_breakpoint
)
2730 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2732 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2733 regcache_read_pc (regcache
))
2734 == ordinary_breakpoint_here
)
2737 tp
->stepping_over_breakpoint
= 0;
2743 /* Check whether thread TP still needs to start a step-over in order
2744 to make progress when resumed. Returns an bitwise or of enum
2745 step_over_what bits, indicating what needs to be stepped over. */
2748 thread_still_needs_step_over (struct thread_info
*tp
)
2750 struct inferior
*inf
= find_inferior_ptid (tp
->ptid
);
2753 if (thread_still_needs_step_over_bp (tp
))
2754 what
|= STEP_OVER_BREAKPOINT
;
2756 if (tp
->stepping_over_watchpoint
2757 && !target_have_steppable_watchpoint
)
2758 what
|= STEP_OVER_WATCHPOINT
;
2763 /* Returns true if scheduler locking applies. STEP indicates whether
2764 we're about to do a step/next-like command to a thread. */
2767 schedlock_applies (struct thread_info
*tp
)
2769 return (scheduler_mode
== schedlock_on
2770 || (scheduler_mode
== schedlock_step
2771 && tp
->control
.stepping_command
));
2774 /* Basic routine for continuing the program in various fashions.
2776 ADDR is the address to resume at, or -1 for resume where stopped.
2777 SIGGNAL is the signal to give it, or 0 for none,
2778 or -1 for act according to how it stopped.
2779 STEP is nonzero if should trap after one instruction.
2780 -1 means return after that and print nothing.
2781 You should probably set various step_... variables
2782 before calling here, if you are stepping.
2784 You should call clear_proceed_status before calling proceed. */
2787 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2789 struct regcache
*regcache
;
2790 struct gdbarch
*gdbarch
;
2791 struct thread_info
*tp
;
2793 struct address_space
*aspace
;
2795 struct execution_control_state ecss
;
2796 struct execution_control_state
*ecs
= &ecss
;
2797 struct cleanup
*old_chain
;
2800 /* If we're stopped at a fork/vfork, follow the branch set by the
2801 "set follow-fork-mode" command; otherwise, we'll just proceed
2802 resuming the current thread. */
2803 if (!follow_fork ())
2805 /* The target for some reason decided not to resume. */
2807 if (target_can_async_p ())
2808 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2812 /* We'll update this if & when we switch to a new thread. */
2813 previous_inferior_ptid
= inferior_ptid
;
2815 regcache
= get_current_regcache ();
2816 gdbarch
= get_regcache_arch (regcache
);
2817 aspace
= get_regcache_aspace (regcache
);
2818 pc
= regcache_read_pc (regcache
);
2819 tp
= inferior_thread ();
2821 /* Fill in with reasonable starting values. */
2822 init_thread_stepping_state (tp
);
2824 gdb_assert (!thread_is_in_step_over_chain (tp
));
2826 if (addr
== (CORE_ADDR
) -1)
2829 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
2830 && execution_direction
!= EXEC_REVERSE
)
2831 /* There is a breakpoint at the address we will resume at,
2832 step one instruction before inserting breakpoints so that
2833 we do not stop right away (and report a second hit at this
2836 Note, we don't do this in reverse, because we won't
2837 actually be executing the breakpoint insn anyway.
2838 We'll be (un-)executing the previous instruction. */
2839 tp
->stepping_over_breakpoint
= 1;
2840 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2841 && gdbarch_single_step_through_delay (gdbarch
,
2842 get_current_frame ()))
2843 /* We stepped onto an instruction that needs to be stepped
2844 again before re-inserting the breakpoint, do so. */
2845 tp
->stepping_over_breakpoint
= 1;
2849 regcache_write_pc (regcache
, addr
);
2852 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2853 tp
->suspend
.stop_signal
= siggnal
;
2855 /* Record the interpreter that issued the execution command that
2856 caused this thread to resume. If the top level interpreter is
2857 MI/async, and the execution command was a CLI command
2858 (next/step/etc.), we'll want to print stop event output to the MI
2859 console channel (the stepped-to line, etc.), as if the user
2860 entered the execution command on a real GDB console. */
2861 tp
->control
.command_interp
= command_interp ();
2863 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
2865 /* If an exception is thrown from this point on, make sure to
2866 propagate GDB's knowledge of the executing state to the
2867 frontend/user running state. */
2868 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
2870 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
2871 threads (e.g., we might need to set threads stepping over
2872 breakpoints first), from the user/frontend's point of view, all
2873 threads in RESUME_PTID are now running. Unless we're calling an
2874 inferior function, as in that case we pretend the inferior
2875 doesn't run at all. */
2876 if (!tp
->control
.in_infcall
)
2877 set_running (resume_ptid
, 1);
2880 fprintf_unfiltered (gdb_stdlog
,
2881 "infrun: proceed (addr=%s, signal=%s)\n",
2882 paddress (gdbarch
, addr
),
2883 gdb_signal_to_symbol_string (siggnal
));
2885 annotate_starting ();
2887 /* Make sure that output from GDB appears before output from the
2889 gdb_flush (gdb_stdout
);
2891 /* In a multi-threaded task we may select another thread and
2892 then continue or step.
2894 But if a thread that we're resuming had stopped at a breakpoint,
2895 it will immediately cause another breakpoint stop without any
2896 execution (i.e. it will report a breakpoint hit incorrectly). So
2897 we must step over it first.
2899 Look for threads other than the current (TP) that reported a
2900 breakpoint hit and haven't been resumed yet since. */
2902 /* If scheduler locking applies, we can avoid iterating over all
2904 if (!non_stop
&& !schedlock_applies (tp
))
2906 struct thread_info
*current
= tp
;
2908 ALL_NON_EXITED_THREADS (tp
)
2910 /* Ignore the current thread here. It's handled
2915 /* Ignore threads of processes we're not resuming. */
2916 if (!ptid_match (tp
->ptid
, resume_ptid
))
2919 if (!thread_still_needs_step_over (tp
))
2922 gdb_assert (!thread_is_in_step_over_chain (tp
));
2925 fprintf_unfiltered (gdb_stdlog
,
2926 "infrun: need to step-over [%s] first\n",
2927 target_pid_to_str (tp
->ptid
));
2929 thread_step_over_chain_enqueue (tp
);
2935 /* Enqueue the current thread last, so that we move all other
2936 threads over their breakpoints first. */
2937 if (tp
->stepping_over_breakpoint
)
2938 thread_step_over_chain_enqueue (tp
);
2940 /* If the thread isn't started, we'll still need to set its prev_pc,
2941 so that switch_back_to_stepped_thread knows the thread hasn't
2942 advanced. Must do this before resuming any thread, as in
2943 all-stop/remote, once we resume we can't send any other packet
2944 until the target stops again. */
2945 tp
->prev_pc
= regcache_read_pc (regcache
);
2947 started
= start_step_over ();
2949 if (step_over_info_valid_p ())
2951 /* Either this thread started a new in-line step over, or some
2952 other thread was already doing one. In either case, don't
2953 resume anything else until the step-over is finished. */
2955 else if (started
&& !target_is_non_stop_p ())
2957 /* A new displaced stepping sequence was started. In all-stop,
2958 we can't talk to the target anymore until it next stops. */
2960 else if (!non_stop
&& target_is_non_stop_p ())
2962 /* In all-stop, but the target is always in non-stop mode.
2963 Start all other threads that are implicitly resumed too. */
2964 ALL_NON_EXITED_THREADS (tp
)
2966 /* Ignore threads of processes we're not resuming. */
2967 if (!ptid_match (tp
->ptid
, resume_ptid
))
2973 fprintf_unfiltered (gdb_stdlog
,
2974 "infrun: proceed: [%s] resumed\n",
2975 target_pid_to_str (tp
->ptid
));
2976 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
2980 if (thread_is_in_step_over_chain (tp
))
2983 fprintf_unfiltered (gdb_stdlog
,
2984 "infrun: proceed: [%s] needs step-over\n",
2985 target_pid_to_str (tp
->ptid
));
2990 fprintf_unfiltered (gdb_stdlog
,
2991 "infrun: proceed: resuming %s\n",
2992 target_pid_to_str (tp
->ptid
));
2994 reset_ecs (ecs
, tp
);
2995 switch_to_thread (tp
->ptid
);
2996 keep_going_pass_signal (ecs
);
2997 if (!ecs
->wait_some_more
)
2998 error ("Command aborted.");
3001 else if (!tp
->resumed
&& !thread_is_in_step_over_chain (tp
))
3003 /* The thread wasn't started, and isn't queued, run it now. */
3004 reset_ecs (ecs
, tp
);
3005 switch_to_thread (tp
->ptid
);
3006 keep_going_pass_signal (ecs
);
3007 if (!ecs
->wait_some_more
)
3008 error ("Command aborted.");
3011 discard_cleanups (old_chain
);
3013 /* Wait for it to stop (if not standalone)
3014 and in any case decode why it stopped, and act accordingly. */
3015 /* Do this only if we are not using the event loop, or if the target
3016 does not support asynchronous execution. */
3017 if (!target_can_async_p ())
3019 wait_for_inferior ();
3025 /* Start remote-debugging of a machine over a serial link. */
3028 start_remote (int from_tty
)
3030 struct inferior
*inferior
;
3032 inferior
= current_inferior ();
3033 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3035 /* Always go on waiting for the target, regardless of the mode. */
3036 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3037 indicate to wait_for_inferior that a target should timeout if
3038 nothing is returned (instead of just blocking). Because of this,
3039 targets expecting an immediate response need to, internally, set
3040 things up so that the target_wait() is forced to eventually
3042 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3043 differentiate to its caller what the state of the target is after
3044 the initial open has been performed. Here we're assuming that
3045 the target has stopped. It should be possible to eventually have
3046 target_open() return to the caller an indication that the target
3047 is currently running and GDB state should be set to the same as
3048 for an async run. */
3049 wait_for_inferior ();
3051 /* Now that the inferior has stopped, do any bookkeeping like
3052 loading shared libraries. We want to do this before normal_stop,
3053 so that the displayed frame is up to date. */
3054 post_create_inferior (¤t_target
, from_tty
);
3059 /* Initialize static vars when a new inferior begins. */
3062 init_wait_for_inferior (void)
3064 /* These are meaningless until the first time through wait_for_inferior. */
3066 breakpoint_init_inferior (inf_starting
);
3068 clear_proceed_status (0);
3070 target_last_wait_ptid
= minus_one_ptid
;
3072 previous_inferior_ptid
= inferior_ptid
;
3074 /* Discard any skipped inlined frames. */
3075 clear_inline_frame_state (minus_one_ptid
);
3080 static void handle_inferior_event (struct execution_control_state
*ecs
);
3082 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3083 struct execution_control_state
*ecs
);
3084 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3085 struct execution_control_state
*ecs
);
3086 static void handle_signal_stop (struct execution_control_state
*ecs
);
3087 static void check_exception_resume (struct execution_control_state
*,
3088 struct frame_info
*);
3090 static void end_stepping_range (struct execution_control_state
*ecs
);
3091 static void stop_waiting (struct execution_control_state
*ecs
);
3092 static void keep_going (struct execution_control_state
*ecs
);
3093 static void process_event_stop_test (struct execution_control_state
*ecs
);
3094 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3096 /* Callback for iterate over threads. If the thread is stopped, but
3097 the user/frontend doesn't know about that yet, go through
3098 normal_stop, as if the thread had just stopped now. ARG points at
3099 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
3100 ptid_is_pid(PTID) is true, applies to all threads of the process
3101 pointed at by PTID. Otherwise, apply only to the thread pointed by
3105 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
3107 ptid_t ptid
= * (ptid_t
*) arg
;
3109 if ((ptid_equal (info
->ptid
, ptid
)
3110 || ptid_equal (minus_one_ptid
, ptid
)
3111 || (ptid_is_pid (ptid
)
3112 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
3113 && is_running (info
->ptid
)
3114 && !is_executing (info
->ptid
))
3116 struct cleanup
*old_chain
;
3117 struct execution_control_state ecss
;
3118 struct execution_control_state
*ecs
= &ecss
;
3120 memset (ecs
, 0, sizeof (*ecs
));
3122 old_chain
= make_cleanup_restore_current_thread ();
3124 overlay_cache_invalid
= 1;
3125 /* Flush target cache before starting to handle each event.
3126 Target was running and cache could be stale. This is just a
3127 heuristic. Running threads may modify target memory, but we
3128 don't get any event. */
3129 target_dcache_invalidate ();
3131 /* Go through handle_inferior_event/normal_stop, so we always
3132 have consistent output as if the stop event had been
3134 ecs
->ptid
= info
->ptid
;
3135 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
3136 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
3137 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
3139 handle_inferior_event (ecs
);
3141 if (!ecs
->wait_some_more
)
3143 struct thread_info
*tp
;
3147 /* Finish off the continuations. */
3148 tp
= inferior_thread ();
3149 do_all_intermediate_continuations_thread (tp
, 1);
3150 do_all_continuations_thread (tp
, 1);
3153 do_cleanups (old_chain
);
3159 /* This function is attached as a "thread_stop_requested" observer.
3160 Cleanup local state that assumed the PTID was to be resumed, and
3161 report the stop to the frontend. */
3164 infrun_thread_stop_requested (ptid_t ptid
)
3166 struct thread_info
*tp
;
3168 /* PTID was requested to stop. Remove matching threads from the
3169 step-over queue, so we don't try to resume them
3171 ALL_NON_EXITED_THREADS (tp
)
3172 if (ptid_match (tp
->ptid
, ptid
))
3174 if (thread_is_in_step_over_chain (tp
))
3175 thread_step_over_chain_remove (tp
);
3178 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
3182 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3184 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3185 nullify_last_target_wait_ptid ();
3188 /* Delete the step resume, single-step and longjmp/exception resume
3189 breakpoints of TP. */
3192 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3194 delete_step_resume_breakpoint (tp
);
3195 delete_exception_resume_breakpoint (tp
);
3196 delete_single_step_breakpoints (tp
);
3199 /* If the target still has execution, call FUNC for each thread that
3200 just stopped. In all-stop, that's all the non-exited threads; in
3201 non-stop, that's the current thread, only. */
3203 typedef void (*for_each_just_stopped_thread_callback_func
)
3204 (struct thread_info
*tp
);
3207 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3209 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3212 if (target_is_non_stop_p ())
3214 /* If in non-stop mode, only the current thread stopped. */
3215 func (inferior_thread ());
3219 struct thread_info
*tp
;
3221 /* In all-stop mode, all threads have stopped. */
3222 ALL_NON_EXITED_THREADS (tp
)
3229 /* Delete the step resume and longjmp/exception resume breakpoints of
3230 the threads that just stopped. */
3233 delete_just_stopped_threads_infrun_breakpoints (void)
3235 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3238 /* Delete the single-step breakpoints of the threads that just
3242 delete_just_stopped_threads_single_step_breakpoints (void)
3244 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3247 /* A cleanup wrapper. */
3250 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3252 delete_just_stopped_threads_infrun_breakpoints ();
3255 /* Pretty print the results of target_wait, for debugging purposes. */
3258 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3259 const struct target_waitstatus
*ws
)
3261 char *status_string
= target_waitstatus_to_string (ws
);
3262 struct ui_file
*tmp_stream
= mem_fileopen ();
3265 /* The text is split over several lines because it was getting too long.
3266 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3267 output as a unit; we want only one timestamp printed if debug_timestamp
3270 fprintf_unfiltered (tmp_stream
,
3271 "infrun: target_wait (%d.%ld.%ld",
3272 ptid_get_pid (waiton_ptid
),
3273 ptid_get_lwp (waiton_ptid
),
3274 ptid_get_tid (waiton_ptid
));
3275 if (ptid_get_pid (waiton_ptid
) != -1)
3276 fprintf_unfiltered (tmp_stream
,
3277 " [%s]", target_pid_to_str (waiton_ptid
));
3278 fprintf_unfiltered (tmp_stream
, ", status) =\n");
3279 fprintf_unfiltered (tmp_stream
,
3280 "infrun: %d.%ld.%ld [%s],\n",
3281 ptid_get_pid (result_ptid
),
3282 ptid_get_lwp (result_ptid
),
3283 ptid_get_tid (result_ptid
),
3284 target_pid_to_str (result_ptid
));
3285 fprintf_unfiltered (tmp_stream
,
3289 text
= ui_file_xstrdup (tmp_stream
, NULL
);
3291 /* This uses %s in part to handle %'s in the text, but also to avoid
3292 a gcc error: the format attribute requires a string literal. */
3293 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
3295 xfree (status_string
);
3297 ui_file_delete (tmp_stream
);
3300 /* Select a thread at random, out of those which are resumed and have
3303 static struct thread_info
*
3304 random_pending_event_thread (ptid_t waiton_ptid
)
3306 struct thread_info
*event_tp
;
3308 int random_selector
;
3310 /* First see how many events we have. Count only resumed threads
3311 that have an event pending. */
3312 ALL_NON_EXITED_THREADS (event_tp
)
3313 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3314 && event_tp
->resumed
3315 && event_tp
->suspend
.waitstatus_pending_p
)
3318 if (num_events
== 0)
3321 /* Now randomly pick a thread out of those that have had events. */
3322 random_selector
= (int)
3323 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3325 if (debug_infrun
&& num_events
> 1)
3326 fprintf_unfiltered (gdb_stdlog
,
3327 "infrun: Found %d events, selecting #%d\n",
3328 num_events
, random_selector
);
3330 /* Select the Nth thread that has had an event. */
3331 ALL_NON_EXITED_THREADS (event_tp
)
3332 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3333 && event_tp
->resumed
3334 && event_tp
->suspend
.waitstatus_pending_p
)
3335 if (random_selector
-- == 0)
3341 /* Wrapper for target_wait that first checks whether threads have
3342 pending statuses to report before actually asking the target for
3346 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3349 struct thread_info
*tp
;
3351 /* First check if there is a resumed thread with a wait status
3353 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
3355 tp
= random_pending_event_thread (ptid
);
3360 fprintf_unfiltered (gdb_stdlog
,
3361 "infrun: Waiting for specific thread %s.\n",
3362 target_pid_to_str (ptid
));
3364 /* We have a specific thread to check. */
3365 tp
= find_thread_ptid (ptid
);
3366 gdb_assert (tp
!= NULL
);
3367 if (!tp
->suspend
.waitstatus_pending_p
)
3372 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3373 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3375 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
3376 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3380 pc
= regcache_read_pc (regcache
);
3382 if (pc
!= tp
->suspend
.stop_pc
)
3385 fprintf_unfiltered (gdb_stdlog
,
3386 "infrun: PC of %s changed. was=%s, now=%s\n",
3387 target_pid_to_str (tp
->ptid
),
3388 paddress (gdbarch
, tp
->prev_pc
),
3389 paddress (gdbarch
, pc
));
3392 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3395 fprintf_unfiltered (gdb_stdlog
,
3396 "infrun: previous breakpoint of %s, at %s gone\n",
3397 target_pid_to_str (tp
->ptid
),
3398 paddress (gdbarch
, pc
));
3406 fprintf_unfiltered (gdb_stdlog
,
3407 "infrun: pending event of %s cancelled.\n",
3408 target_pid_to_str (tp
->ptid
));
3410 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3411 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3421 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3422 fprintf_unfiltered (gdb_stdlog
,
3423 "infrun: Using pending wait status %s for %s.\n",
3425 target_pid_to_str (tp
->ptid
));
3429 /* Now that we've selected our final event LWP, un-adjust its PC
3430 if it was a software breakpoint (and the target doesn't
3431 always adjust the PC itself). */
3432 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3433 && !target_supports_stopped_by_sw_breakpoint ())
3435 struct regcache
*regcache
;
3436 struct gdbarch
*gdbarch
;
3439 regcache
= get_thread_regcache (tp
->ptid
);
3440 gdbarch
= get_regcache_arch (regcache
);
3442 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3447 pc
= regcache_read_pc (regcache
);
3448 regcache_write_pc (regcache
, pc
+ decr_pc
);
3452 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3453 *status
= tp
->suspend
.waitstatus
;
3454 tp
->suspend
.waitstatus_pending_p
= 0;
3456 /* Wake up the event loop again, until all pending events are
3458 if (target_is_async_p ())
3459 mark_async_event_handler (infrun_async_inferior_event_token
);
3463 /* But if we don't find one, we'll have to wait. */
3465 if (deprecated_target_wait_hook
)
3466 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3468 event_ptid
= target_wait (ptid
, status
, options
);
3473 /* Prepare and stabilize the inferior for detaching it. E.g.,
3474 detaching while a thread is displaced stepping is a recipe for
3475 crashing it, as nothing would readjust the PC out of the scratch
3479 prepare_for_detach (void)
3481 struct inferior
*inf
= current_inferior ();
3482 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3483 struct cleanup
*old_chain_1
;
3484 struct displaced_step_inferior_state
*displaced
;
3486 displaced
= get_displaced_stepping_state (inf
->pid
);
3488 /* Is any thread of this process displaced stepping? If not,
3489 there's nothing else to do. */
3490 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3494 fprintf_unfiltered (gdb_stdlog
,
3495 "displaced-stepping in-process while detaching");
3497 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3500 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3502 struct cleanup
*old_chain_2
;
3503 struct execution_control_state ecss
;
3504 struct execution_control_state
*ecs
;
3507 memset (ecs
, 0, sizeof (*ecs
));
3509 overlay_cache_invalid
= 1;
3510 /* Flush target cache before starting to handle each event.
3511 Target was running and cache could be stale. This is just a
3512 heuristic. Running threads may modify target memory, but we
3513 don't get any event. */
3514 target_dcache_invalidate ();
3516 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3519 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3521 /* If an error happens while handling the event, propagate GDB's
3522 knowledge of the executing state to the frontend/user running
3524 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3527 /* Now figure out what to do with the result of the result. */
3528 handle_inferior_event (ecs
);
3530 /* No error, don't finish the state yet. */
3531 discard_cleanups (old_chain_2
);
3533 /* Breakpoints and watchpoints are not installed on the target
3534 at this point, and signals are passed directly to the
3535 inferior, so this must mean the process is gone. */
3536 if (!ecs
->wait_some_more
)
3538 discard_cleanups (old_chain_1
);
3539 error (_("Program exited while detaching"));
3543 discard_cleanups (old_chain_1
);
3546 /* Wait for control to return from inferior to debugger.
3548 If inferior gets a signal, we may decide to start it up again
3549 instead of returning. That is why there is a loop in this function.
3550 When this function actually returns it means the inferior
3551 should be left stopped and GDB should read more commands. */
3554 wait_for_inferior (void)
3556 struct cleanup
*old_cleanups
;
3557 struct cleanup
*thread_state_chain
;
3561 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3564 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3567 /* If an error happens while handling the event, propagate GDB's
3568 knowledge of the executing state to the frontend/user running
3570 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3574 struct execution_control_state ecss
;
3575 struct execution_control_state
*ecs
= &ecss
;
3576 ptid_t waiton_ptid
= minus_one_ptid
;
3578 memset (ecs
, 0, sizeof (*ecs
));
3580 overlay_cache_invalid
= 1;
3582 /* Flush target cache before starting to handle each event.
3583 Target was running and cache could be stale. This is just a
3584 heuristic. Running threads may modify target memory, but we
3585 don't get any event. */
3586 target_dcache_invalidate ();
3588 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3591 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3593 /* Now figure out what to do with the result of the result. */
3594 handle_inferior_event (ecs
);
3596 if (!ecs
->wait_some_more
)
3600 /* No error, don't finish the state yet. */
3601 discard_cleanups (thread_state_chain
);
3603 do_cleanups (old_cleanups
);
3606 /* Cleanup that reinstalls the readline callback handler, if the
3607 target is running in the background. If while handling the target
3608 event something triggered a secondary prompt, like e.g., a
3609 pagination prompt, we'll have removed the callback handler (see
3610 gdb_readline_wrapper_line). Need to do this as we go back to the
3611 event loop, ready to process further input. Note this has no
3612 effect if the handler hasn't actually been removed, because calling
3613 rl_callback_handler_install resets the line buffer, thus losing
3617 reinstall_readline_callback_handler_cleanup (void *arg
)
3619 if (!interpreter_async
)
3621 /* We're not going back to the top level event loop yet. Don't
3622 install the readline callback, as it'd prep the terminal,
3623 readline-style (raw, noecho) (e.g., --batch). We'll install
3624 it the next time the prompt is displayed, when we're ready
3629 if (async_command_editing_p
&& !sync_execution
)
3630 gdb_rl_callback_handler_reinstall ();
3633 /* Asynchronous version of wait_for_inferior. It is called by the
3634 event loop whenever a change of state is detected on the file
3635 descriptor corresponding to the target. It can be called more than
3636 once to complete a single execution command. In such cases we need
3637 to keep the state in a global variable ECSS. If it is the last time
3638 that this function is called for a single execution command, then
3639 report to the user that the inferior has stopped, and do the
3640 necessary cleanups. */
3643 fetch_inferior_event (void *client_data
)
3645 struct execution_control_state ecss
;
3646 struct execution_control_state
*ecs
= &ecss
;
3647 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3648 struct cleanup
*ts_old_chain
;
3649 int was_sync
= sync_execution
;
3651 ptid_t waiton_ptid
= minus_one_ptid
;
3653 memset (ecs
, 0, sizeof (*ecs
));
3655 /* End up with readline processing input, if necessary. */
3656 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3658 /* We're handling a live event, so make sure we're doing live
3659 debugging. If we're looking at traceframes while the target is
3660 running, we're going to need to get back to that mode after
3661 handling the event. */
3664 make_cleanup_restore_current_traceframe ();
3665 set_current_traceframe (-1);
3669 /* In non-stop mode, the user/frontend should not notice a thread
3670 switch due to internal events. Make sure we reverse to the
3671 user selected thread and frame after handling the event and
3672 running any breakpoint commands. */
3673 make_cleanup_restore_current_thread ();
3675 overlay_cache_invalid
= 1;
3676 /* Flush target cache before starting to handle each event. Target
3677 was running and cache could be stale. This is just a heuristic.
3678 Running threads may modify target memory, but we don't get any
3680 target_dcache_invalidate ();
3682 make_cleanup_restore_integer (&execution_direction
);
3683 execution_direction
= target_execution_direction ();
3685 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3688 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3690 /* If an error happens while handling the event, propagate GDB's
3691 knowledge of the executing state to the frontend/user running
3693 if (!target_is_non_stop_p ())
3694 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3696 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3698 /* Get executed before make_cleanup_restore_current_thread above to apply
3699 still for the thread which has thrown the exception. */
3700 make_bpstat_clear_actions_cleanup ();
3702 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3704 /* Now figure out what to do with the result of the result. */
3705 handle_inferior_event (ecs
);
3707 if (!ecs
->wait_some_more
)
3709 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3711 delete_just_stopped_threads_infrun_breakpoints ();
3713 /* We may not find an inferior if this was a process exit. */
3714 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3717 if (target_has_execution
3718 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
3719 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3720 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3721 && ecs
->event_thread
->step_multi
3722 && ecs
->event_thread
->control
.stop_step
)
3723 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
3726 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3731 /* No error, don't finish the thread states yet. */
3732 discard_cleanups (ts_old_chain
);
3734 /* Revert thread and frame. */
3735 do_cleanups (old_chain
);
3737 /* If the inferior was in sync execution mode, and now isn't,
3738 restore the prompt (a synchronous execution command has finished,
3739 and we're ready for input). */
3740 if (interpreter_async
&& was_sync
&& !sync_execution
)
3741 observer_notify_sync_execution_done ();
3745 && exec_done_display_p
3746 && (ptid_equal (inferior_ptid
, null_ptid
)
3747 || !is_running (inferior_ptid
)))
3748 printf_unfiltered (_("completed.\n"));
3751 /* Record the frame and location we're currently stepping through. */
3753 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3755 struct thread_info
*tp
= inferior_thread ();
3757 tp
->control
.step_frame_id
= get_frame_id (frame
);
3758 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
3760 tp
->current_symtab
= sal
.symtab
;
3761 tp
->current_line
= sal
.line
;
3764 /* Clear context switchable stepping state. */
3767 init_thread_stepping_state (struct thread_info
*tss
)
3769 tss
->stepped_breakpoint
= 0;
3770 tss
->stepping_over_breakpoint
= 0;
3771 tss
->stepping_over_watchpoint
= 0;
3772 tss
->step_after_step_resume_breakpoint
= 0;
3775 /* Set the cached copy of the last ptid/waitstatus. */
3778 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
3780 target_last_wait_ptid
= ptid
;
3781 target_last_waitstatus
= status
;
3784 /* Return the cached copy of the last pid/waitstatus returned by
3785 target_wait()/deprecated_target_wait_hook(). The data is actually
3786 cached by handle_inferior_event(), which gets called immediately
3787 after target_wait()/deprecated_target_wait_hook(). */
3790 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
3792 *ptidp
= target_last_wait_ptid
;
3793 *status
= target_last_waitstatus
;
3797 nullify_last_target_wait_ptid (void)
3799 target_last_wait_ptid
= minus_one_ptid
;
3802 /* Switch thread contexts. */
3805 context_switch (ptid_t ptid
)
3807 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
3809 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
3810 target_pid_to_str (inferior_ptid
));
3811 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
3812 target_pid_to_str (ptid
));
3815 switch_to_thread (ptid
);
3818 /* If the target can't tell whether we've hit breakpoints
3819 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
3820 check whether that could have been caused by a breakpoint. If so,
3821 adjust the PC, per gdbarch_decr_pc_after_break. */
3824 adjust_pc_after_break (struct thread_info
*thread
,
3825 struct target_waitstatus
*ws
)
3827 struct regcache
*regcache
;
3828 struct gdbarch
*gdbarch
;
3829 struct address_space
*aspace
;
3830 CORE_ADDR breakpoint_pc
, decr_pc
;
3832 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
3833 we aren't, just return.
3835 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
3836 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
3837 implemented by software breakpoints should be handled through the normal
3840 NOTE drow/2004-01-31: On some targets, breakpoints may generate
3841 different signals (SIGILL or SIGEMT for instance), but it is less
3842 clear where the PC is pointing afterwards. It may not match
3843 gdbarch_decr_pc_after_break. I don't know any specific target that
3844 generates these signals at breakpoints (the code has been in GDB since at
3845 least 1992) so I can not guess how to handle them here.
3847 In earlier versions of GDB, a target with
3848 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
3849 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
3850 target with both of these set in GDB history, and it seems unlikely to be
3851 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
3853 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
3856 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
3859 /* In reverse execution, when a breakpoint is hit, the instruction
3860 under it has already been de-executed. The reported PC always
3861 points at the breakpoint address, so adjusting it further would
3862 be wrong. E.g., consider this case on a decr_pc_after_break == 1
3865 B1 0x08000000 : INSN1
3866 B2 0x08000001 : INSN2
3868 PC -> 0x08000003 : INSN4
3870 Say you're stopped at 0x08000003 as above. Reverse continuing
3871 from that point should hit B2 as below. Reading the PC when the
3872 SIGTRAP is reported should read 0x08000001 and INSN2 should have
3873 been de-executed already.
3875 B1 0x08000000 : INSN1
3876 B2 PC -> 0x08000001 : INSN2
3880 We can't apply the same logic as for forward execution, because
3881 we would wrongly adjust the PC to 0x08000000, since there's a
3882 breakpoint at PC - 1. We'd then report a hit on B1, although
3883 INSN1 hadn't been de-executed yet. Doing nothing is the correct
3885 if (execution_direction
== EXEC_REVERSE
)
3888 /* If the target can tell whether the thread hit a SW breakpoint,
3889 trust it. Targets that can tell also adjust the PC
3891 if (target_supports_stopped_by_sw_breakpoint ())
3894 /* Note that relying on whether a breakpoint is planted in memory to
3895 determine this can fail. E.g,. the breakpoint could have been
3896 removed since. Or the thread could have been told to step an
3897 instruction the size of a breakpoint instruction, and only
3898 _after_ was a breakpoint inserted at its address. */
3900 /* If this target does not decrement the PC after breakpoints, then
3901 we have nothing to do. */
3902 regcache
= get_thread_regcache (thread
->ptid
);
3903 gdbarch
= get_regcache_arch (regcache
);
3905 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3909 aspace
= get_regcache_aspace (regcache
);
3911 /* Find the location where (if we've hit a breakpoint) the
3912 breakpoint would be. */
3913 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
3915 /* If the target can't tell whether a software breakpoint triggered,
3916 fallback to figuring it out based on breakpoints we think were
3917 inserted in the target, and on whether the thread was stepped or
3920 /* Check whether there actually is a software breakpoint inserted at
3923 If in non-stop mode, a race condition is possible where we've
3924 removed a breakpoint, but stop events for that breakpoint were
3925 already queued and arrive later. To suppress those spurious
3926 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3927 and retire them after a number of stop events are reported. Note
3928 this is an heuristic and can thus get confused. The real fix is
3929 to get the "stopped by SW BP and needs adjustment" info out of
3930 the target/kernel (and thus never reach here; see above). */
3931 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3932 || (target_is_non_stop_p ()
3933 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3935 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
3937 if (record_full_is_used ())
3938 record_full_gdb_operation_disable_set ();
3940 /* When using hardware single-step, a SIGTRAP is reported for both
3941 a completed single-step and a software breakpoint. Need to
3942 differentiate between the two, as the latter needs adjusting
3943 but the former does not.
3945 The SIGTRAP can be due to a completed hardware single-step only if
3946 - we didn't insert software single-step breakpoints
3947 - this thread is currently being stepped
3949 If any of these events did not occur, we must have stopped due
3950 to hitting a software breakpoint, and have to back up to the
3953 As a special case, we could have hardware single-stepped a
3954 software breakpoint. In this case (prev_pc == breakpoint_pc),
3955 we also need to back up to the breakpoint address. */
3957 if (thread_has_single_step_breakpoints_set (thread
)
3958 || !currently_stepping (thread
)
3959 || (thread
->stepped_breakpoint
3960 && thread
->prev_pc
== breakpoint_pc
))
3961 regcache_write_pc (regcache
, breakpoint_pc
);
3963 do_cleanups (old_cleanups
);
3968 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3970 for (frame
= get_prev_frame (frame
);
3972 frame
= get_prev_frame (frame
))
3974 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3976 if (get_frame_type (frame
) != INLINE_FRAME
)
3983 /* Auxiliary function that handles syscall entry/return events.
3984 It returns 1 if the inferior should keep going (and GDB
3985 should ignore the event), or 0 if the event deserves to be
3989 handle_syscall_event (struct execution_control_state
*ecs
)
3991 struct regcache
*regcache
;
3994 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3995 context_switch (ecs
->ptid
);
3997 regcache
= get_thread_regcache (ecs
->ptid
);
3998 syscall_number
= ecs
->ws
.value
.syscall_number
;
3999 stop_pc
= regcache_read_pc (regcache
);
4001 if (catch_syscall_enabled () > 0
4002 && catching_syscall_number (syscall_number
) > 0)
4005 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4008 ecs
->event_thread
->control
.stop_bpstat
4009 = bpstat_stop_status (get_regcache_aspace (regcache
),
4010 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4012 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4014 /* Catchpoint hit. */
4019 /* If no catchpoint triggered for this, then keep going. */
4024 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4027 fill_in_stop_func (struct gdbarch
*gdbarch
,
4028 struct execution_control_state
*ecs
)
4030 if (!ecs
->stop_func_filled_in
)
4032 /* Don't care about return value; stop_func_start and stop_func_name
4033 will both be 0 if it doesn't work. */
4034 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4035 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4036 ecs
->stop_func_start
4037 += gdbarch_deprecated_function_start_offset (gdbarch
);
4039 if (gdbarch_skip_entrypoint_p (gdbarch
))
4040 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4041 ecs
->stop_func_start
);
4043 ecs
->stop_func_filled_in
= 1;
4048 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4050 static enum stop_kind
4051 get_inferior_stop_soon (ptid_t ptid
)
4053 struct inferior
*inf
= find_inferior_ptid (ptid
);
4055 gdb_assert (inf
!= NULL
);
4056 return inf
->control
.stop_soon
;
4059 /* Wait for one event. Store the resulting waitstatus in WS, and
4060 return the event ptid. */
4063 wait_one (struct target_waitstatus
*ws
)
4066 ptid_t wait_ptid
= minus_one_ptid
;
4068 overlay_cache_invalid
= 1;
4070 /* Flush target cache before starting to handle each event.
4071 Target was running and cache could be stale. This is just a
4072 heuristic. Running threads may modify target memory, but we
4073 don't get any event. */
4074 target_dcache_invalidate ();
4076 if (deprecated_target_wait_hook
)
4077 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4079 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4082 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4087 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4088 instead of the current thread. */
4089 #define THREAD_STOPPED_BY(REASON) \
4091 thread_stopped_by_ ## REASON (ptid_t ptid) \
4093 struct cleanup *old_chain; \
4096 old_chain = save_inferior_ptid (); \
4097 inferior_ptid = ptid; \
4099 res = target_stopped_by_ ## REASON (); \
4101 do_cleanups (old_chain); \
4106 /* Generate thread_stopped_by_watchpoint. */
4107 THREAD_STOPPED_BY (watchpoint
)
4108 /* Generate thread_stopped_by_sw_breakpoint. */
4109 THREAD_STOPPED_BY (sw_breakpoint
)
4110 /* Generate thread_stopped_by_hw_breakpoint. */
4111 THREAD_STOPPED_BY (hw_breakpoint
)
4113 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4116 switch_to_thread_cleanup (void *ptid_p
)
4118 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4120 switch_to_thread (ptid
);
4123 /* Save the thread's event and stop reason to process it later. */
4126 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4128 struct regcache
*regcache
;
4129 struct address_space
*aspace
;
4135 statstr
= target_waitstatus_to_string (ws
);
4136 fprintf_unfiltered (gdb_stdlog
,
4137 "infrun: saving status %s for %d.%ld.%ld\n",
4139 ptid_get_pid (tp
->ptid
),
4140 ptid_get_lwp (tp
->ptid
),
4141 ptid_get_tid (tp
->ptid
));
4145 /* Record for later. */
4146 tp
->suspend
.waitstatus
= *ws
;
4147 tp
->suspend
.waitstatus_pending_p
= 1;
4149 regcache
= get_thread_regcache (tp
->ptid
);
4150 aspace
= get_regcache_aspace (regcache
);
4152 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4153 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4155 CORE_ADDR pc
= regcache_read_pc (regcache
);
4157 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4159 if (thread_stopped_by_watchpoint (tp
->ptid
))
4161 tp
->suspend
.stop_reason
4162 = TARGET_STOPPED_BY_WATCHPOINT
;
4164 else if (target_supports_stopped_by_sw_breakpoint ()
4165 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4167 tp
->suspend
.stop_reason
4168 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4170 else if (target_supports_stopped_by_hw_breakpoint ()
4171 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4173 tp
->suspend
.stop_reason
4174 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4176 else if (!target_supports_stopped_by_hw_breakpoint ()
4177 && hardware_breakpoint_inserted_here_p (aspace
,
4180 tp
->suspend
.stop_reason
4181 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4183 else if (!target_supports_stopped_by_sw_breakpoint ()
4184 && software_breakpoint_inserted_here_p (aspace
,
4187 tp
->suspend
.stop_reason
4188 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4190 else if (!thread_has_single_step_breakpoints_set (tp
)
4191 && currently_stepping (tp
))
4193 tp
->suspend
.stop_reason
4194 = TARGET_STOPPED_BY_SINGLE_STEP
;
4199 /* Stop all threads. */
4202 stop_all_threads (void)
4204 /* We may need multiple passes to discover all threads. */
4208 struct cleanup
*old_chain
;
4210 gdb_assert (target_is_non_stop_p ());
4213 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4215 entry_ptid
= inferior_ptid
;
4216 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4218 /* Request threads to stop, and then wait for the stops. Because
4219 threads we already know about can spawn more threads while we're
4220 trying to stop them, and we only learn about new threads when we
4221 update the thread list, do this in a loop, and keep iterating
4222 until two passes find no threads that need to be stopped. */
4223 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4226 fprintf_unfiltered (gdb_stdlog
,
4227 "infrun: stop_all_threads, pass=%d, "
4228 "iterations=%d\n", pass
, iterations
);
4232 struct target_waitstatus ws
;
4234 struct thread_info
*t
;
4236 update_thread_list ();
4238 /* Go through all threads looking for threads that we need
4239 to tell the target to stop. */
4240 ALL_NON_EXITED_THREADS (t
)
4244 /* If already stopping, don't request a stop again.
4245 We just haven't seen the notification yet. */
4246 if (!t
->stop_requested
)
4249 fprintf_unfiltered (gdb_stdlog
,
4250 "infrun: %s executing, "
4252 target_pid_to_str (t
->ptid
));
4253 target_stop (t
->ptid
);
4254 t
->stop_requested
= 1;
4259 fprintf_unfiltered (gdb_stdlog
,
4260 "infrun: %s executing, "
4261 "already stopping\n",
4262 target_pid_to_str (t
->ptid
));
4265 if (t
->stop_requested
)
4271 fprintf_unfiltered (gdb_stdlog
,
4272 "infrun: %s not executing\n",
4273 target_pid_to_str (t
->ptid
));
4275 /* The thread may be not executing, but still be
4276 resumed with a pending status to process. */
4284 /* If we find new threads on the second iteration, restart
4285 over. We want to see two iterations in a row with all
4290 event_ptid
= wait_one (&ws
);
4291 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4293 /* All resumed threads exited. */
4295 else if (ws
.kind
== TARGET_WAITKIND_EXITED
4296 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4300 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4302 fprintf_unfiltered (gdb_stdlog
,
4303 "infrun: %s exited while "
4304 "stopping threads\n",
4305 target_pid_to_str (ptid
));
4310 t
= find_thread_ptid (event_ptid
);
4312 t
= add_thread (event_ptid
);
4314 t
->stop_requested
= 0;
4317 t
->control
.may_range_step
= 0;
4319 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4320 && ws
.value
.sig
== GDB_SIGNAL_0
)
4322 /* We caught the event that we intended to catch, so
4323 there's no event pending. */
4324 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4325 t
->suspend
.waitstatus_pending_p
= 0;
4327 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4329 /* Add it back to the step-over queue. */
4332 fprintf_unfiltered (gdb_stdlog
,
4333 "infrun: displaced-step of %s "
4334 "canceled: adding back to the "
4335 "step-over queue\n",
4336 target_pid_to_str (t
->ptid
));
4338 t
->control
.trap_expected
= 0;
4339 thread_step_over_chain_enqueue (t
);
4344 enum gdb_signal sig
;
4345 struct regcache
*regcache
;
4346 struct address_space
*aspace
;
4352 statstr
= target_waitstatus_to_string (&ws
);
4353 fprintf_unfiltered (gdb_stdlog
,
4354 "infrun: target_wait %s, saving "
4355 "status for %d.%ld.%ld\n",
4357 ptid_get_pid (t
->ptid
),
4358 ptid_get_lwp (t
->ptid
),
4359 ptid_get_tid (t
->ptid
));
4363 /* Record for later. */
4364 save_waitstatus (t
, &ws
);
4366 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4367 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4369 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4371 /* Add it back to the step-over queue. */
4372 t
->control
.trap_expected
= 0;
4373 thread_step_over_chain_enqueue (t
);
4376 regcache
= get_thread_regcache (t
->ptid
);
4377 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4381 fprintf_unfiltered (gdb_stdlog
,
4382 "infrun: saved stop_pc=%s for %s "
4383 "(currently_stepping=%d)\n",
4384 paddress (target_gdbarch (),
4385 t
->suspend
.stop_pc
),
4386 target_pid_to_str (t
->ptid
),
4387 currently_stepping (t
));
4394 do_cleanups (old_chain
);
4397 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4400 /* Given an execution control state that has been freshly filled in by
4401 an event from the inferior, figure out what it means and take
4404 The alternatives are:
4406 1) stop_waiting and return; to really stop and return to the
4409 2) keep_going and return; to wait for the next event (set
4410 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4414 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4416 enum stop_kind stop_soon
;
4418 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4420 /* We had an event in the inferior, but we are not interested in
4421 handling it at this level. The lower layers have already
4422 done what needs to be done, if anything.
4424 One of the possible circumstances for this is when the
4425 inferior produces output for the console. The inferior has
4426 not stopped, and we are ignoring the event. Another possible
4427 circumstance is any event which the lower level knows will be
4428 reported multiple times without an intervening resume. */
4430 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4431 prepare_to_wait (ecs
);
4435 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4436 && target_can_async_p () && !sync_execution
)
4438 /* There were no unwaited-for children left in the target, but,
4439 we're not synchronously waiting for events either. Just
4440 ignore. Otherwise, if we were running a synchronous
4441 execution command, we need to cancel it and give the user
4442 back the terminal. */
4444 fprintf_unfiltered (gdb_stdlog
,
4445 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
4446 prepare_to_wait (ecs
);
4450 /* Cache the last pid/waitstatus. */
4451 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4453 /* Always clear state belonging to the previous time we stopped. */
4454 stop_stack_dummy
= STOP_NONE
;
4456 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4458 /* No unwaited-for children left. IOW, all resumed children
4461 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4463 stop_print_frame
= 0;
4468 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4469 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4471 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4472 /* If it's a new thread, add it to the thread database. */
4473 if (ecs
->event_thread
== NULL
)
4474 ecs
->event_thread
= add_thread (ecs
->ptid
);
4476 /* Disable range stepping. If the next step request could use a
4477 range, this will be end up re-enabled then. */
4478 ecs
->event_thread
->control
.may_range_step
= 0;
4481 /* Dependent on valid ECS->EVENT_THREAD. */
4482 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4484 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4485 reinit_frame_cache ();
4487 breakpoint_retire_moribund ();
4489 /* First, distinguish signals caused by the debugger from signals
4490 that have to do with the program's own actions. Note that
4491 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4492 on the operating system version. Here we detect when a SIGILL or
4493 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4494 something similar for SIGSEGV, since a SIGSEGV will be generated
4495 when we're trying to execute a breakpoint instruction on a
4496 non-executable stack. This happens for call dummy breakpoints
4497 for architectures like SPARC that place call dummies on the
4499 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4500 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4501 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4502 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4504 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4506 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
4507 regcache_read_pc (regcache
)))
4510 fprintf_unfiltered (gdb_stdlog
,
4511 "infrun: Treating signal as SIGTRAP\n");
4512 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4516 /* Mark the non-executing threads accordingly. In all-stop, all
4517 threads of all processes are stopped when we get any event
4518 reported. In non-stop mode, only the event thread stops. */
4522 if (!target_is_non_stop_p ())
4523 mark_ptid
= minus_one_ptid
;
4524 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4525 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4527 /* If we're handling a process exit in non-stop mode, even
4528 though threads haven't been deleted yet, one would think
4529 that there is nothing to do, as threads of the dead process
4530 will be soon deleted, and threads of any other process were
4531 left running. However, on some targets, threads survive a
4532 process exit event. E.g., for the "checkpoint" command,
4533 when the current checkpoint/fork exits, linux-fork.c
4534 automatically switches to another fork from within
4535 target_mourn_inferior, by associating the same
4536 inferior/thread to another fork. We haven't mourned yet at
4537 this point, but we must mark any threads left in the
4538 process as not-executing so that finish_thread_state marks
4539 them stopped (in the user's perspective) if/when we present
4540 the stop to the user. */
4541 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4544 mark_ptid
= ecs
->ptid
;
4546 set_executing (mark_ptid
, 0);
4548 /* Likewise the resumed flag. */
4549 set_resumed (mark_ptid
, 0);
4552 switch (ecs
->ws
.kind
)
4554 case TARGET_WAITKIND_LOADED
:
4556 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4557 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4558 context_switch (ecs
->ptid
);
4559 /* Ignore gracefully during startup of the inferior, as it might
4560 be the shell which has just loaded some objects, otherwise
4561 add the symbols for the newly loaded objects. Also ignore at
4562 the beginning of an attach or remote session; we will query
4563 the full list of libraries once the connection is
4566 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4567 if (stop_soon
== NO_STOP_QUIETLY
)
4569 struct regcache
*regcache
;
4571 regcache
= get_thread_regcache (ecs
->ptid
);
4573 handle_solib_event ();
4575 ecs
->event_thread
->control
.stop_bpstat
4576 = bpstat_stop_status (get_regcache_aspace (regcache
),
4577 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4579 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4581 /* A catchpoint triggered. */
4582 process_event_stop_test (ecs
);
4586 /* If requested, stop when the dynamic linker notifies
4587 gdb of events. This allows the user to get control
4588 and place breakpoints in initializer routines for
4589 dynamically loaded objects (among other things). */
4590 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4591 if (stop_on_solib_events
)
4593 /* Make sure we print "Stopped due to solib-event" in
4595 stop_print_frame
= 1;
4602 /* If we are skipping through a shell, or through shared library
4603 loading that we aren't interested in, resume the program. If
4604 we're running the program normally, also resume. */
4605 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
4607 /* Loading of shared libraries might have changed breakpoint
4608 addresses. Make sure new breakpoints are inserted. */
4609 if (stop_soon
== NO_STOP_QUIETLY
)
4610 insert_breakpoints ();
4611 resume (GDB_SIGNAL_0
);
4612 prepare_to_wait (ecs
);
4616 /* But stop if we're attaching or setting up a remote
4618 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4619 || stop_soon
== STOP_QUIETLY_REMOTE
)
4622 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4627 internal_error (__FILE__
, __LINE__
,
4628 _("unhandled stop_soon: %d"), (int) stop_soon
);
4630 case TARGET_WAITKIND_SPURIOUS
:
4632 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
4633 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4634 context_switch (ecs
->ptid
);
4635 resume (GDB_SIGNAL_0
);
4636 prepare_to_wait (ecs
);
4639 case TARGET_WAITKIND_EXITED
:
4640 case TARGET_WAITKIND_SIGNALLED
:
4643 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4644 fprintf_unfiltered (gdb_stdlog
,
4645 "infrun: TARGET_WAITKIND_EXITED\n");
4647 fprintf_unfiltered (gdb_stdlog
,
4648 "infrun: TARGET_WAITKIND_SIGNALLED\n");
4651 inferior_ptid
= ecs
->ptid
;
4652 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
4653 set_current_program_space (current_inferior ()->pspace
);
4654 handle_vfork_child_exec_or_exit (0);
4655 target_terminal_ours (); /* Must do this before mourn anyway. */
4657 /* Clearing any previous state of convenience variables. */
4658 clear_exit_convenience_vars ();
4660 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4662 /* Record the exit code in the convenience variable $_exitcode, so
4663 that the user can inspect this again later. */
4664 set_internalvar_integer (lookup_internalvar ("_exitcode"),
4665 (LONGEST
) ecs
->ws
.value
.integer
);
4667 /* Also record this in the inferior itself. */
4668 current_inferior ()->has_exit_code
= 1;
4669 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
4671 /* Support the --return-child-result option. */
4672 return_child_result_value
= ecs
->ws
.value
.integer
;
4674 observer_notify_exited (ecs
->ws
.value
.integer
);
4678 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4679 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4681 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
4683 /* Set the value of the internal variable $_exitsignal,
4684 which holds the signal uncaught by the inferior. */
4685 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
4686 gdbarch_gdb_signal_to_target (gdbarch
,
4687 ecs
->ws
.value
.sig
));
4691 /* We don't have access to the target's method used for
4692 converting between signal numbers (GDB's internal
4693 representation <-> target's representation).
4694 Therefore, we cannot do a good job at displaying this
4695 information to the user. It's better to just warn
4696 her about it (if infrun debugging is enabled), and
4699 fprintf_filtered (gdb_stdlog
, _("\
4700 Cannot fill $_exitsignal with the correct signal number.\n"));
4703 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
4706 gdb_flush (gdb_stdout
);
4707 target_mourn_inferior ();
4708 stop_print_frame
= 0;
4712 /* The following are the only cases in which we keep going;
4713 the above cases end in a continue or goto. */
4714 case TARGET_WAITKIND_FORKED
:
4715 case TARGET_WAITKIND_VFORKED
:
4718 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
4719 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
4721 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
4724 /* Check whether the inferior is displaced stepping. */
4726 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4727 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4728 struct displaced_step_inferior_state
*displaced
4729 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
4731 /* If checking displaced stepping is supported, and thread
4732 ecs->ptid is displaced stepping. */
4733 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
4735 struct inferior
*parent_inf
4736 = find_inferior_ptid (ecs
->ptid
);
4737 struct regcache
*child_regcache
;
4738 CORE_ADDR parent_pc
;
4740 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
4741 indicating that the displaced stepping of syscall instruction
4742 has been done. Perform cleanup for parent process here. Note
4743 that this operation also cleans up the child process for vfork,
4744 because their pages are shared. */
4745 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
4746 /* Start a new step-over in another thread if there's one
4750 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
4752 /* Restore scratch pad for child process. */
4753 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
4756 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
4757 the child's PC is also within the scratchpad. Set the child's PC
4758 to the parent's PC value, which has already been fixed up.
4759 FIXME: we use the parent's aspace here, although we're touching
4760 the child, because the child hasn't been added to the inferior
4761 list yet at this point. */
4764 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
4766 parent_inf
->aspace
);
4767 /* Read PC value of parent process. */
4768 parent_pc
= regcache_read_pc (regcache
);
4770 if (debug_displaced
)
4771 fprintf_unfiltered (gdb_stdlog
,
4772 "displaced: write child pc from %s to %s\n",
4774 regcache_read_pc (child_regcache
)),
4775 paddress (gdbarch
, parent_pc
));
4777 regcache_write_pc (child_regcache
, parent_pc
);
4781 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4782 context_switch (ecs
->ptid
);
4784 /* Immediately detach breakpoints from the child before there's
4785 any chance of letting the user delete breakpoints from the
4786 breakpoint lists. If we don't do this early, it's easy to
4787 leave left over traps in the child, vis: "break foo; catch
4788 fork; c; <fork>; del; c; <child calls foo>". We only follow
4789 the fork on the last `continue', and by that time the
4790 breakpoint at "foo" is long gone from the breakpoint table.
4791 If we vforked, then we don't need to unpatch here, since both
4792 parent and child are sharing the same memory pages; we'll
4793 need to unpatch at follow/detach time instead to be certain
4794 that new breakpoints added between catchpoint hit time and
4795 vfork follow are detached. */
4796 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
4798 /* This won't actually modify the breakpoint list, but will
4799 physically remove the breakpoints from the child. */
4800 detach_breakpoints (ecs
->ws
.value
.related_pid
);
4803 delete_just_stopped_threads_single_step_breakpoints ();
4805 /* In case the event is caught by a catchpoint, remember that
4806 the event is to be followed at the next resume of the thread,
4807 and not immediately. */
4808 ecs
->event_thread
->pending_follow
= ecs
->ws
;
4810 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4812 ecs
->event_thread
->control
.stop_bpstat
4813 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4814 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4816 /* If no catchpoint triggered for this, then keep going. Note
4817 that we're interested in knowing the bpstat actually causes a
4818 stop, not just if it may explain the signal. Software
4819 watchpoints, for example, always appear in the bpstat. */
4820 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4826 = (follow_fork_mode_string
== follow_fork_mode_child
);
4828 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4830 should_resume
= follow_fork ();
4833 child
= ecs
->ws
.value
.related_pid
;
4835 /* In non-stop mode, also resume the other branch. */
4836 if (!detach_fork
&& (non_stop
4837 || (sched_multi
&& target_is_non_stop_p ())))
4840 switch_to_thread (parent
);
4842 switch_to_thread (child
);
4844 ecs
->event_thread
= inferior_thread ();
4845 ecs
->ptid
= inferior_ptid
;
4850 switch_to_thread (child
);
4852 switch_to_thread (parent
);
4854 ecs
->event_thread
= inferior_thread ();
4855 ecs
->ptid
= inferior_ptid
;
4863 process_event_stop_test (ecs
);
4866 case TARGET_WAITKIND_VFORK_DONE
:
4867 /* Done with the shared memory region. Re-insert breakpoints in
4868 the parent, and keep going. */
4871 fprintf_unfiltered (gdb_stdlog
,
4872 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
4874 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4875 context_switch (ecs
->ptid
);
4877 current_inferior ()->waiting_for_vfork_done
= 0;
4878 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
4879 /* This also takes care of reinserting breakpoints in the
4880 previously locked inferior. */
4884 case TARGET_WAITKIND_EXECD
:
4886 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
4888 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4889 context_switch (ecs
->ptid
);
4891 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4893 /* Do whatever is necessary to the parent branch of the vfork. */
4894 handle_vfork_child_exec_or_exit (1);
4896 /* This causes the eventpoints and symbol table to be reset.
4897 Must do this now, before trying to determine whether to
4899 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
4901 ecs
->event_thread
->control
.stop_bpstat
4902 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4903 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4905 /* Note that this may be referenced from inside
4906 bpstat_stop_status above, through inferior_has_execd. */
4907 xfree (ecs
->ws
.value
.execd_pathname
);
4908 ecs
->ws
.value
.execd_pathname
= NULL
;
4910 /* If no catchpoint triggered for this, then keep going. */
4911 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4913 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4917 process_event_stop_test (ecs
);
4920 /* Be careful not to try to gather much state about a thread
4921 that's in a syscall. It's frequently a losing proposition. */
4922 case TARGET_WAITKIND_SYSCALL_ENTRY
:
4924 fprintf_unfiltered (gdb_stdlog
,
4925 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
4926 /* Getting the current syscall number. */
4927 if (handle_syscall_event (ecs
) == 0)
4928 process_event_stop_test (ecs
);
4931 /* Before examining the threads further, step this thread to
4932 get it entirely out of the syscall. (We get notice of the
4933 event when the thread is just on the verge of exiting a
4934 syscall. Stepping one instruction seems to get it back
4936 case TARGET_WAITKIND_SYSCALL_RETURN
:
4938 fprintf_unfiltered (gdb_stdlog
,
4939 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
4940 if (handle_syscall_event (ecs
) == 0)
4941 process_event_stop_test (ecs
);
4944 case TARGET_WAITKIND_STOPPED
:
4946 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
4947 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
4948 handle_signal_stop (ecs
);
4951 case TARGET_WAITKIND_NO_HISTORY
:
4953 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
4954 /* Reverse execution: target ran out of history info. */
4956 delete_just_stopped_threads_single_step_breakpoints ();
4957 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4958 observer_notify_no_history ();
4964 /* A wrapper around handle_inferior_event_1, which also makes sure
4965 that all temporary struct value objects that were created during
4966 the handling of the event get deleted at the end. */
4969 handle_inferior_event (struct execution_control_state
*ecs
)
4971 struct value
*mark
= value_mark ();
4973 handle_inferior_event_1 (ecs
);
4974 /* Purge all temporary values created during the event handling,
4975 as it could be a long time before we return to the command level
4976 where such values would otherwise be purged. */
4977 value_free_to_mark (mark
);
4980 /* Restart threads back to what they were trying to do back when we
4981 paused them for an in-line step-over. The EVENT_THREAD thread is
4985 restart_threads (struct thread_info
*event_thread
)
4987 struct thread_info
*tp
;
4988 struct thread_info
*step_over
= NULL
;
4990 /* In case the instruction just stepped spawned a new thread. */
4991 update_thread_list ();
4993 ALL_NON_EXITED_THREADS (tp
)
4995 if (tp
== event_thread
)
4998 fprintf_unfiltered (gdb_stdlog
,
4999 "infrun: restart threads: "
5000 "[%s] is event thread\n",
5001 target_pid_to_str (tp
->ptid
));
5005 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5008 fprintf_unfiltered (gdb_stdlog
,
5009 "infrun: restart threads: "
5010 "[%s] not meant to be running\n",
5011 target_pid_to_str (tp
->ptid
));
5018 fprintf_unfiltered (gdb_stdlog
,
5019 "infrun: restart threads: [%s] resumed\n",
5020 target_pid_to_str (tp
->ptid
));
5021 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5025 if (thread_is_in_step_over_chain (tp
))
5028 fprintf_unfiltered (gdb_stdlog
,
5029 "infrun: restart threads: "
5030 "[%s] needs step-over\n",
5031 target_pid_to_str (tp
->ptid
));
5032 gdb_assert (!tp
->resumed
);
5037 if (tp
->suspend
.waitstatus_pending_p
)
5040 fprintf_unfiltered (gdb_stdlog
,
5041 "infrun: restart threads: "
5042 "[%s] has pending status\n",
5043 target_pid_to_str (tp
->ptid
));
5048 /* If some thread needs to start a step-over at this point, it
5049 should still be in the step-over queue, and thus skipped
5051 if (thread_still_needs_step_over (tp
))
5053 internal_error (__FILE__
, __LINE__
,
5054 "thread [%s] needs a step-over, but not in "
5055 "step-over queue\n",
5056 target_pid_to_str (tp
->ptid
));
5059 if (currently_stepping (tp
))
5062 fprintf_unfiltered (gdb_stdlog
,
5063 "infrun: restart threads: [%s] was stepping\n",
5064 target_pid_to_str (tp
->ptid
));
5065 keep_going_stepped_thread (tp
);
5069 struct execution_control_state ecss
;
5070 struct execution_control_state
*ecs
= &ecss
;
5073 fprintf_unfiltered (gdb_stdlog
,
5074 "infrun: restart threads: [%s] continuing\n",
5075 target_pid_to_str (tp
->ptid
));
5076 reset_ecs (ecs
, tp
);
5077 switch_to_thread (tp
->ptid
);
5078 keep_going_pass_signal (ecs
);
5083 /* Callback for iterate_over_threads. Find a resumed thread that has
5084 a pending waitstatus. */
5087 resumed_thread_with_pending_status (struct thread_info
*tp
,
5091 && tp
->suspend
.waitstatus_pending_p
);
5094 /* Called when we get an event that may finish an in-line or
5095 out-of-line (displaced stepping) step-over started previously.
5096 Return true if the event is processed and we should go back to the
5097 event loop; false if the caller should continue processing the
5101 finish_step_over (struct execution_control_state
*ecs
)
5103 int had_step_over_info
;
5105 displaced_step_fixup (ecs
->ptid
,
5106 ecs
->event_thread
->suspend
.stop_signal
);
5108 had_step_over_info
= step_over_info_valid_p ();
5110 if (had_step_over_info
)
5112 /* If we're stepping over a breakpoint with all threads locked,
5113 then only the thread that was stepped should be reporting
5115 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5117 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5118 clear_step_over_info ();
5121 if (!target_is_non_stop_p ())
5124 /* Start a new step-over in another thread if there's one that
5128 /* If we were stepping over a breakpoint before, and haven't started
5129 a new in-line step-over sequence, then restart all other threads
5130 (except the event thread). We can't do this in all-stop, as then
5131 e.g., we wouldn't be able to issue any other remote packet until
5132 these other threads stop. */
5133 if (had_step_over_info
&& !step_over_info_valid_p ())
5135 struct thread_info
*pending
;
5137 /* If we only have threads with pending statuses, the restart
5138 below won't restart any thread and so nothing re-inserts the
5139 breakpoint we just stepped over. But we need it inserted
5140 when we later process the pending events, otherwise if
5141 another thread has a pending event for this breakpoint too,
5142 we'd discard its event (because the breakpoint that
5143 originally caused the event was no longer inserted). */
5144 context_switch (ecs
->ptid
);
5145 insert_breakpoints ();
5147 restart_threads (ecs
->event_thread
);
5149 /* If we have events pending, go through handle_inferior_event
5150 again, picking up a pending event at random. This avoids
5151 thread starvation. */
5153 /* But not if we just stepped over a watchpoint in order to let
5154 the instruction execute so we can evaluate its expression.
5155 The set of watchpoints that triggered is recorded in the
5156 breakpoint objects themselves (see bp->watchpoint_triggered).
5157 If we processed another event first, that other event could
5158 clobber this info. */
5159 if (ecs
->event_thread
->stepping_over_watchpoint
)
5162 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5164 if (pending
!= NULL
)
5166 struct thread_info
*tp
= ecs
->event_thread
;
5167 struct regcache
*regcache
;
5171 fprintf_unfiltered (gdb_stdlog
,
5172 "infrun: found resumed threads with "
5173 "pending events, saving status\n");
5176 gdb_assert (pending
!= tp
);
5178 /* Record the event thread's event for later. */
5179 save_waitstatus (tp
, &ecs
->ws
);
5180 /* This was cleared early, by handle_inferior_event. Set it
5181 so this pending event is considered by
5185 gdb_assert (!tp
->executing
);
5187 regcache
= get_thread_regcache (tp
->ptid
);
5188 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5192 fprintf_unfiltered (gdb_stdlog
,
5193 "infrun: saved stop_pc=%s for %s "
5194 "(currently_stepping=%d)\n",
5195 paddress (target_gdbarch (),
5196 tp
->suspend
.stop_pc
),
5197 target_pid_to_str (tp
->ptid
),
5198 currently_stepping (tp
));
5201 /* This in-line step-over finished; clear this so we won't
5202 start a new one. This is what handle_signal_stop would
5203 do, if we returned false. */
5204 tp
->stepping_over_breakpoint
= 0;
5206 /* Wake up the event loop again. */
5207 mark_async_event_handler (infrun_async_inferior_event_token
);
5209 prepare_to_wait (ecs
);
5217 /* Come here when the program has stopped with a signal. */
5220 handle_signal_stop (struct execution_control_state
*ecs
)
5222 struct frame_info
*frame
;
5223 struct gdbarch
*gdbarch
;
5224 int stopped_by_watchpoint
;
5225 enum stop_kind stop_soon
;
5228 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5230 /* Do we need to clean up the state of a thread that has
5231 completed a displaced single-step? (Doing so usually affects
5232 the PC, so do it here, before we set stop_pc.) */
5233 if (finish_step_over (ecs
))
5236 /* If we either finished a single-step or hit a breakpoint, but
5237 the user wanted this thread to be stopped, pretend we got a
5238 SIG0 (generic unsignaled stop). */
5239 if (ecs
->event_thread
->stop_requested
5240 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5241 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5243 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5247 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5248 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5249 struct cleanup
*old_chain
= save_inferior_ptid ();
5251 inferior_ptid
= ecs
->ptid
;
5253 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5254 paddress (gdbarch
, stop_pc
));
5255 if (target_stopped_by_watchpoint ())
5259 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5261 if (target_stopped_data_address (¤t_target
, &addr
))
5262 fprintf_unfiltered (gdb_stdlog
,
5263 "infrun: stopped data address = %s\n",
5264 paddress (gdbarch
, addr
));
5266 fprintf_unfiltered (gdb_stdlog
,
5267 "infrun: (no data address available)\n");
5270 do_cleanups (old_chain
);
5273 /* This is originated from start_remote(), start_inferior() and
5274 shared libraries hook functions. */
5275 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5276 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5278 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5279 context_switch (ecs
->ptid
);
5281 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5282 stop_print_frame
= 1;
5287 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5290 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5291 context_switch (ecs
->ptid
);
5293 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5294 stop_print_frame
= 0;
5299 /* This originates from attach_command(). We need to overwrite
5300 the stop_signal here, because some kernels don't ignore a
5301 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5302 See more comments in inferior.h. On the other hand, if we
5303 get a non-SIGSTOP, report it to the user - assume the backend
5304 will handle the SIGSTOP if it should show up later.
5306 Also consider that the attach is complete when we see a
5307 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5308 target extended-remote report it instead of a SIGSTOP
5309 (e.g. gdbserver). We already rely on SIGTRAP being our
5310 signal, so this is no exception.
5312 Also consider that the attach is complete when we see a
5313 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5314 the target to stop all threads of the inferior, in case the
5315 low level attach operation doesn't stop them implicitly. If
5316 they weren't stopped implicitly, then the stub will report a
5317 GDB_SIGNAL_0, meaning: stopped for no particular reason
5318 other than GDB's request. */
5319 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5320 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5321 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5322 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5324 stop_print_frame
= 1;
5326 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5330 /* See if something interesting happened to the non-current thread. If
5331 so, then switch to that thread. */
5332 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5335 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5337 context_switch (ecs
->ptid
);
5339 if (deprecated_context_hook
)
5340 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
5343 /* At this point, get hold of the now-current thread's frame. */
5344 frame
= get_current_frame ();
5345 gdbarch
= get_frame_arch (frame
);
5347 /* Pull the single step breakpoints out of the target. */
5348 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5350 struct regcache
*regcache
;
5351 struct address_space
*aspace
;
5354 regcache
= get_thread_regcache (ecs
->ptid
);
5355 aspace
= get_regcache_aspace (regcache
);
5356 pc
= regcache_read_pc (regcache
);
5358 /* However, before doing so, if this single-step breakpoint was
5359 actually for another thread, set this thread up for moving
5361 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5364 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5368 fprintf_unfiltered (gdb_stdlog
,
5369 "infrun: [%s] hit another thread's "
5370 "single-step breakpoint\n",
5371 target_pid_to_str (ecs
->ptid
));
5373 ecs
->hit_singlestep_breakpoint
= 1;
5380 fprintf_unfiltered (gdb_stdlog
,
5381 "infrun: [%s] hit its "
5382 "single-step breakpoint\n",
5383 target_pid_to_str (ecs
->ptid
));
5387 delete_just_stopped_threads_single_step_breakpoints ();
5389 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5390 && ecs
->event_thread
->control
.trap_expected
5391 && ecs
->event_thread
->stepping_over_watchpoint
)
5392 stopped_by_watchpoint
= 0;
5394 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5396 /* If necessary, step over this watchpoint. We'll be back to display
5398 if (stopped_by_watchpoint
5399 && (target_have_steppable_watchpoint
5400 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5402 /* At this point, we are stopped at an instruction which has
5403 attempted to write to a piece of memory under control of
5404 a watchpoint. The instruction hasn't actually executed
5405 yet. If we were to evaluate the watchpoint expression
5406 now, we would get the old value, and therefore no change
5407 would seem to have occurred.
5409 In order to make watchpoints work `right', we really need
5410 to complete the memory write, and then evaluate the
5411 watchpoint expression. We do this by single-stepping the
5414 It may not be necessary to disable the watchpoint to step over
5415 it. For example, the PA can (with some kernel cooperation)
5416 single step over a watchpoint without disabling the watchpoint.
5418 It is far more common to need to disable a watchpoint to step
5419 the inferior over it. If we have non-steppable watchpoints,
5420 we must disable the current watchpoint; it's simplest to
5421 disable all watchpoints.
5423 Any breakpoint at PC must also be stepped over -- if there's
5424 one, it will have already triggered before the watchpoint
5425 triggered, and we either already reported it to the user, or
5426 it didn't cause a stop and we called keep_going. In either
5427 case, if there was a breakpoint at PC, we must be trying to
5429 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5434 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5435 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5436 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5437 ecs
->event_thread
->control
.stop_step
= 0;
5438 stop_print_frame
= 1;
5439 stopped_by_random_signal
= 0;
5441 /* Hide inlined functions starting here, unless we just performed stepi or
5442 nexti. After stepi and nexti, always show the innermost frame (not any
5443 inline function call sites). */
5444 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5446 struct address_space
*aspace
=
5447 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
5449 /* skip_inline_frames is expensive, so we avoid it if we can
5450 determine that the address is one where functions cannot have
5451 been inlined. This improves performance with inferiors that
5452 load a lot of shared libraries, because the solib event
5453 breakpoint is defined as the address of a function (i.e. not
5454 inline). Note that we have to check the previous PC as well
5455 as the current one to catch cases when we have just
5456 single-stepped off a breakpoint prior to reinstating it.
5457 Note that we're assuming that the code we single-step to is
5458 not inline, but that's not definitive: there's nothing
5459 preventing the event breakpoint function from containing
5460 inlined code, and the single-step ending up there. If the
5461 user had set a breakpoint on that inlined code, the missing
5462 skip_inline_frames call would break things. Fortunately
5463 that's an extremely unlikely scenario. */
5464 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5465 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5466 && ecs
->event_thread
->control
.trap_expected
5467 && pc_at_non_inline_function (aspace
,
5468 ecs
->event_thread
->prev_pc
,
5471 skip_inline_frames (ecs
->ptid
);
5473 /* Re-fetch current thread's frame in case that invalidated
5475 frame
= get_current_frame ();
5476 gdbarch
= get_frame_arch (frame
);
5480 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5481 && ecs
->event_thread
->control
.trap_expected
5482 && gdbarch_single_step_through_delay_p (gdbarch
)
5483 && currently_stepping (ecs
->event_thread
))
5485 /* We're trying to step off a breakpoint. Turns out that we're
5486 also on an instruction that needs to be stepped multiple
5487 times before it's been fully executing. E.g., architectures
5488 with a delay slot. It needs to be stepped twice, once for
5489 the instruction and once for the delay slot. */
5490 int step_through_delay
5491 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5493 if (debug_infrun
&& step_through_delay
)
5494 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5495 if (ecs
->event_thread
->control
.step_range_end
== 0
5496 && step_through_delay
)
5498 /* The user issued a continue when stopped at a breakpoint.
5499 Set up for another trap and get out of here. */
5500 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5504 else if (step_through_delay
)
5506 /* The user issued a step when stopped at a breakpoint.
5507 Maybe we should stop, maybe we should not - the delay
5508 slot *might* correspond to a line of source. In any
5509 case, don't decide that here, just set
5510 ecs->stepping_over_breakpoint, making sure we
5511 single-step again before breakpoints are re-inserted. */
5512 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5516 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5517 handles this event. */
5518 ecs
->event_thread
->control
.stop_bpstat
5519 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5520 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5522 /* Following in case break condition called a
5524 stop_print_frame
= 1;
5526 /* This is where we handle "moribund" watchpoints. Unlike
5527 software breakpoints traps, hardware watchpoint traps are
5528 always distinguishable from random traps. If no high-level
5529 watchpoint is associated with the reported stop data address
5530 anymore, then the bpstat does not explain the signal ---
5531 simply make sure to ignore it if `stopped_by_watchpoint' is
5535 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5536 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5538 && stopped_by_watchpoint
)
5539 fprintf_unfiltered (gdb_stdlog
,
5540 "infrun: no user watchpoint explains "
5541 "watchpoint SIGTRAP, ignoring\n");
5543 /* NOTE: cagney/2003-03-29: These checks for a random signal
5544 at one stage in the past included checks for an inferior
5545 function call's call dummy's return breakpoint. The original
5546 comment, that went with the test, read:
5548 ``End of a stack dummy. Some systems (e.g. Sony news) give
5549 another signal besides SIGTRAP, so check here as well as
5552 If someone ever tries to get call dummys on a
5553 non-executable stack to work (where the target would stop
5554 with something like a SIGSEGV), then those tests might need
5555 to be re-instated. Given, however, that the tests were only
5556 enabled when momentary breakpoints were not being used, I
5557 suspect that it won't be the case.
5559 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5560 be necessary for call dummies on a non-executable stack on
5563 /* See if the breakpoints module can explain the signal. */
5565 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5566 ecs
->event_thread
->suspend
.stop_signal
);
5568 /* Maybe this was a trap for a software breakpoint that has since
5570 if (random_signal
&& target_stopped_by_sw_breakpoint ())
5572 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
5574 struct regcache
*regcache
;
5577 /* Re-adjust PC to what the program would see if GDB was not
5579 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
5580 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
5583 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
5585 if (record_full_is_used ())
5586 record_full_gdb_operation_disable_set ();
5588 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
5590 do_cleanups (old_cleanups
);
5595 /* A delayed software breakpoint event. Ignore the trap. */
5597 fprintf_unfiltered (gdb_stdlog
,
5598 "infrun: delayed software breakpoint "
5599 "trap, ignoring\n");
5604 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
5605 has since been removed. */
5606 if (random_signal
&& target_stopped_by_hw_breakpoint ())
5608 /* A delayed hardware breakpoint event. Ignore the trap. */
5610 fprintf_unfiltered (gdb_stdlog
,
5611 "infrun: delayed hardware breakpoint/watchpoint "
5612 "trap, ignoring\n");
5616 /* If not, perhaps stepping/nexting can. */
5618 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5619 && currently_stepping (ecs
->event_thread
));
5621 /* Perhaps the thread hit a single-step breakpoint of _another_
5622 thread. Single-step breakpoints are transparent to the
5623 breakpoints module. */
5625 random_signal
= !ecs
->hit_singlestep_breakpoint
;
5627 /* No? Perhaps we got a moribund watchpoint. */
5629 random_signal
= !stopped_by_watchpoint
;
5631 /* For the program's own signals, act according to
5632 the signal handling tables. */
5636 /* Signal not for debugging purposes. */
5637 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
5638 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
5641 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
5642 gdb_signal_to_symbol_string (stop_signal
));
5644 stopped_by_random_signal
= 1;
5646 /* Always stop on signals if we're either just gaining control
5647 of the program, or the user explicitly requested this thread
5648 to remain stopped. */
5649 if (stop_soon
!= NO_STOP_QUIETLY
5650 || ecs
->event_thread
->stop_requested
5652 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
5658 /* Notify observers the signal has "handle print" set. Note we
5659 returned early above if stopping; normal_stop handles the
5660 printing in that case. */
5661 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
5663 /* The signal table tells us to print about this signal. */
5664 target_terminal_ours_for_output ();
5665 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
5666 target_terminal_inferior ();
5669 /* Clear the signal if it should not be passed. */
5670 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
5671 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5673 if (ecs
->event_thread
->prev_pc
== stop_pc
5674 && ecs
->event_thread
->control
.trap_expected
5675 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5679 /* We were just starting a new sequence, attempting to
5680 single-step off of a breakpoint and expecting a SIGTRAP.
5681 Instead this signal arrives. This signal will take us out
5682 of the stepping range so GDB needs to remember to, when
5683 the signal handler returns, resume stepping off that
5685 /* To simplify things, "continue" is forced to use the same
5686 code paths as single-step - set a breakpoint at the
5687 signal return address and then, once hit, step off that
5690 fprintf_unfiltered (gdb_stdlog
,
5691 "infrun: signal arrived while stepping over "
5694 was_in_line
= step_over_info_valid_p ();
5695 clear_step_over_info ();
5696 insert_hp_step_resume_breakpoint_at_frame (frame
);
5697 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5698 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5699 ecs
->event_thread
->control
.trap_expected
= 0;
5701 if (target_is_non_stop_p ())
5703 /* Either "set non-stop" is "on", or the target is
5704 always in non-stop mode. In this case, we have a bit
5705 more work to do. Resume the current thread, and if
5706 we had paused all threads, restart them while the
5707 signal handler runs. */
5712 restart_threads (ecs
->event_thread
);
5714 else if (debug_infrun
)
5716 fprintf_unfiltered (gdb_stdlog
,
5717 "infrun: no need to restart threads\n");
5722 /* If we were nexting/stepping some other thread, switch to
5723 it, so that we don't continue it, losing control. */
5724 if (!switch_back_to_stepped_thread (ecs
))
5729 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
5730 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
5731 || ecs
->event_thread
->control
.step_range_end
== 1)
5732 && frame_id_eq (get_stack_frame_id (frame
),
5733 ecs
->event_thread
->control
.step_stack_frame_id
)
5734 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5736 /* The inferior is about to take a signal that will take it
5737 out of the single step range. Set a breakpoint at the
5738 current PC (which is presumably where the signal handler
5739 will eventually return) and then allow the inferior to
5742 Note that this is only needed for a signal delivered
5743 while in the single-step range. Nested signals aren't a
5744 problem as they eventually all return. */
5746 fprintf_unfiltered (gdb_stdlog
,
5747 "infrun: signal may take us out of "
5748 "single-step range\n");
5750 clear_step_over_info ();
5751 insert_hp_step_resume_breakpoint_at_frame (frame
);
5752 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5753 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5754 ecs
->event_thread
->control
.trap_expected
= 0;
5759 /* Note: step_resume_breakpoint may be non-NULL. This occures
5760 when either there's a nested signal, or when there's a
5761 pending signal enabled just as the signal handler returns
5762 (leaving the inferior at the step-resume-breakpoint without
5763 actually executing it). Either way continue until the
5764 breakpoint is really hit. */
5766 if (!switch_back_to_stepped_thread (ecs
))
5769 fprintf_unfiltered (gdb_stdlog
,
5770 "infrun: random signal, keep going\n");
5777 process_event_stop_test (ecs
);
5780 /* Come here when we've got some debug event / signal we can explain
5781 (IOW, not a random signal), and test whether it should cause a
5782 stop, or whether we should resume the inferior (transparently).
5783 E.g., could be a breakpoint whose condition evaluates false; we
5784 could be still stepping within the line; etc. */
5787 process_event_stop_test (struct execution_control_state
*ecs
)
5789 struct symtab_and_line stop_pc_sal
;
5790 struct frame_info
*frame
;
5791 struct gdbarch
*gdbarch
;
5792 CORE_ADDR jmp_buf_pc
;
5793 struct bpstat_what what
;
5795 /* Handle cases caused by hitting a breakpoint. */
5797 frame
= get_current_frame ();
5798 gdbarch
= get_frame_arch (frame
);
5800 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
5802 if (what
.call_dummy
)
5804 stop_stack_dummy
= what
.call_dummy
;
5807 /* If we hit an internal event that triggers symbol changes, the
5808 current frame will be invalidated within bpstat_what (e.g., if we
5809 hit an internal solib event). Re-fetch it. */
5810 frame
= get_current_frame ();
5811 gdbarch
= get_frame_arch (frame
);
5813 switch (what
.main_action
)
5815 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
5816 /* If we hit the breakpoint at longjmp while stepping, we
5817 install a momentary breakpoint at the target of the
5821 fprintf_unfiltered (gdb_stdlog
,
5822 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
5824 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5826 if (what
.is_longjmp
)
5828 struct value
*arg_value
;
5830 /* If we set the longjmp breakpoint via a SystemTap probe,
5831 then use it to extract the arguments. The destination PC
5832 is the third argument to the probe. */
5833 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
5836 jmp_buf_pc
= value_as_address (arg_value
);
5837 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
5839 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
5840 || !gdbarch_get_longjmp_target (gdbarch
,
5841 frame
, &jmp_buf_pc
))
5844 fprintf_unfiltered (gdb_stdlog
,
5845 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
5846 "(!gdbarch_get_longjmp_target)\n");
5851 /* Insert a breakpoint at resume address. */
5852 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
5855 check_exception_resume (ecs
, frame
);
5859 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
5861 struct frame_info
*init_frame
;
5863 /* There are several cases to consider.
5865 1. The initiating frame no longer exists. In this case we
5866 must stop, because the exception or longjmp has gone too
5869 2. The initiating frame exists, and is the same as the
5870 current frame. We stop, because the exception or longjmp
5873 3. The initiating frame exists and is different from the
5874 current frame. This means the exception or longjmp has
5875 been caught beneath the initiating frame, so keep going.
5877 4. longjmp breakpoint has been placed just to protect
5878 against stale dummy frames and user is not interested in
5879 stopping around longjmps. */
5882 fprintf_unfiltered (gdb_stdlog
,
5883 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
5885 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
5887 delete_exception_resume_breakpoint (ecs
->event_thread
);
5889 if (what
.is_longjmp
)
5891 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
5893 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
5901 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
5905 struct frame_id current_id
5906 = get_frame_id (get_current_frame ());
5907 if (frame_id_eq (current_id
,
5908 ecs
->event_thread
->initiating_frame
))
5910 /* Case 2. Fall through. */
5920 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
5922 delete_step_resume_breakpoint (ecs
->event_thread
);
5924 end_stepping_range (ecs
);
5928 case BPSTAT_WHAT_SINGLE
:
5930 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
5931 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5932 /* Still need to check other stuff, at least the case where we
5933 are stepping and step out of the right range. */
5936 case BPSTAT_WHAT_STEP_RESUME
:
5938 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
5940 delete_step_resume_breakpoint (ecs
->event_thread
);
5941 if (ecs
->event_thread
->control
.proceed_to_finish
5942 && execution_direction
== EXEC_REVERSE
)
5944 struct thread_info
*tp
= ecs
->event_thread
;
5946 /* We are finishing a function in reverse, and just hit the
5947 step-resume breakpoint at the start address of the
5948 function, and we're almost there -- just need to back up
5949 by one more single-step, which should take us back to the
5951 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
5955 fill_in_stop_func (gdbarch
, ecs
);
5956 if (stop_pc
== ecs
->stop_func_start
5957 && execution_direction
== EXEC_REVERSE
)
5959 /* We are stepping over a function call in reverse, and just
5960 hit the step-resume breakpoint at the start address of
5961 the function. Go back to single-stepping, which should
5962 take us back to the function call. */
5963 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5969 case BPSTAT_WHAT_STOP_NOISY
:
5971 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
5972 stop_print_frame
= 1;
5974 /* Assume the thread stopped for a breapoint. We'll still check
5975 whether a/the breakpoint is there when the thread is next
5977 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5982 case BPSTAT_WHAT_STOP_SILENT
:
5984 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
5985 stop_print_frame
= 0;
5987 /* Assume the thread stopped for a breapoint. We'll still check
5988 whether a/the breakpoint is there when the thread is next
5990 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5994 case BPSTAT_WHAT_HP_STEP_RESUME
:
5996 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
5998 delete_step_resume_breakpoint (ecs
->event_thread
);
5999 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6001 /* Back when the step-resume breakpoint was inserted, we
6002 were trying to single-step off a breakpoint. Go back to
6004 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6005 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6011 case BPSTAT_WHAT_KEEP_CHECKING
:
6015 /* If we stepped a permanent breakpoint and we had a high priority
6016 step-resume breakpoint for the address we stepped, but we didn't
6017 hit it, then we must have stepped into the signal handler. The
6018 step-resume was only necessary to catch the case of _not_
6019 stepping into the handler, so delete it, and fall through to
6020 checking whether the step finished. */
6021 if (ecs
->event_thread
->stepped_breakpoint
)
6023 struct breakpoint
*sr_bp
6024 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6027 && sr_bp
->loc
->permanent
6028 && sr_bp
->type
== bp_hp_step_resume
6029 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6032 fprintf_unfiltered (gdb_stdlog
,
6033 "infrun: stepped permanent breakpoint, stopped in "
6035 delete_step_resume_breakpoint (ecs
->event_thread
);
6036 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6040 /* We come here if we hit a breakpoint but should not stop for it.
6041 Possibly we also were stepping and should stop for that. So fall
6042 through and test for stepping. But, if not stepping, do not
6045 /* In all-stop mode, if we're currently stepping but have stopped in
6046 some other thread, we need to switch back to the stepped thread. */
6047 if (switch_back_to_stepped_thread (ecs
))
6050 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6053 fprintf_unfiltered (gdb_stdlog
,
6054 "infrun: step-resume breakpoint is inserted\n");
6056 /* Having a step-resume breakpoint overrides anything
6057 else having to do with stepping commands until
6058 that breakpoint is reached. */
6063 if (ecs
->event_thread
->control
.step_range_end
== 0)
6066 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6067 /* Likewise if we aren't even stepping. */
6072 /* Re-fetch current thread's frame in case the code above caused
6073 the frame cache to be re-initialized, making our FRAME variable
6074 a dangling pointer. */
6075 frame
= get_current_frame ();
6076 gdbarch
= get_frame_arch (frame
);
6077 fill_in_stop_func (gdbarch
, ecs
);
6079 /* If stepping through a line, keep going if still within it.
6081 Note that step_range_end is the address of the first instruction
6082 beyond the step range, and NOT the address of the last instruction
6085 Note also that during reverse execution, we may be stepping
6086 through a function epilogue and therefore must detect when
6087 the current-frame changes in the middle of a line. */
6089 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6090 && (execution_direction
!= EXEC_REVERSE
6091 || frame_id_eq (get_frame_id (frame
),
6092 ecs
->event_thread
->control
.step_frame_id
)))
6096 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6097 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6098 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6100 /* Tentatively re-enable range stepping; `resume' disables it if
6101 necessary (e.g., if we're stepping over a breakpoint or we
6102 have software watchpoints). */
6103 ecs
->event_thread
->control
.may_range_step
= 1;
6105 /* When stepping backward, stop at beginning of line range
6106 (unless it's the function entry point, in which case
6107 keep going back to the call point). */
6108 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6109 && stop_pc
!= ecs
->stop_func_start
6110 && execution_direction
== EXEC_REVERSE
)
6111 end_stepping_range (ecs
);
6118 /* We stepped out of the stepping range. */
6120 /* If we are stepping at the source level and entered the runtime
6121 loader dynamic symbol resolution code...
6123 EXEC_FORWARD: we keep on single stepping until we exit the run
6124 time loader code and reach the callee's address.
6126 EXEC_REVERSE: we've already executed the callee (backward), and
6127 the runtime loader code is handled just like any other
6128 undebuggable function call. Now we need only keep stepping
6129 backward through the trampoline code, and that's handled further
6130 down, so there is nothing for us to do here. */
6132 if (execution_direction
!= EXEC_REVERSE
6133 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6134 && in_solib_dynsym_resolve_code (stop_pc
))
6136 CORE_ADDR pc_after_resolver
=
6137 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6140 fprintf_unfiltered (gdb_stdlog
,
6141 "infrun: stepped into dynsym resolve code\n");
6143 if (pc_after_resolver
)
6145 /* Set up a step-resume breakpoint at the address
6146 indicated by SKIP_SOLIB_RESOLVER. */
6147 struct symtab_and_line sr_sal
;
6150 sr_sal
.pc
= pc_after_resolver
;
6151 sr_sal
.pspace
= get_frame_program_space (frame
);
6153 insert_step_resume_breakpoint_at_sal (gdbarch
,
6154 sr_sal
, null_frame_id
);
6161 if (ecs
->event_thread
->control
.step_range_end
!= 1
6162 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6163 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6164 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6167 fprintf_unfiltered (gdb_stdlog
,
6168 "infrun: stepped into signal trampoline\n");
6169 /* The inferior, while doing a "step" or "next", has ended up in
6170 a signal trampoline (either by a signal being delivered or by
6171 the signal handler returning). Just single-step until the
6172 inferior leaves the trampoline (either by calling the handler
6178 /* If we're in the return path from a shared library trampoline,
6179 we want to proceed through the trampoline when stepping. */
6180 /* macro/2012-04-25: This needs to come before the subroutine
6181 call check below as on some targets return trampolines look
6182 like subroutine calls (MIPS16 return thunks). */
6183 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6184 stop_pc
, ecs
->stop_func_name
)
6185 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6187 /* Determine where this trampoline returns. */
6188 CORE_ADDR real_stop_pc
;
6190 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6193 fprintf_unfiltered (gdb_stdlog
,
6194 "infrun: stepped into solib return tramp\n");
6196 /* Only proceed through if we know where it's going. */
6199 /* And put the step-breakpoint there and go until there. */
6200 struct symtab_and_line sr_sal
;
6202 init_sal (&sr_sal
); /* initialize to zeroes */
6203 sr_sal
.pc
= real_stop_pc
;
6204 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6205 sr_sal
.pspace
= get_frame_program_space (frame
);
6207 /* Do not specify what the fp should be when we stop since
6208 on some machines the prologue is where the new fp value
6210 insert_step_resume_breakpoint_at_sal (gdbarch
,
6211 sr_sal
, null_frame_id
);
6213 /* Restart without fiddling with the step ranges or
6220 /* Check for subroutine calls. The check for the current frame
6221 equalling the step ID is not necessary - the check of the
6222 previous frame's ID is sufficient - but it is a common case and
6223 cheaper than checking the previous frame's ID.
6225 NOTE: frame_id_eq will never report two invalid frame IDs as
6226 being equal, so to get into this block, both the current and
6227 previous frame must have valid frame IDs. */
6228 /* The outer_frame_id check is a heuristic to detect stepping
6229 through startup code. If we step over an instruction which
6230 sets the stack pointer from an invalid value to a valid value,
6231 we may detect that as a subroutine call from the mythical
6232 "outermost" function. This could be fixed by marking
6233 outermost frames as !stack_p,code_p,special_p. Then the
6234 initial outermost frame, before sp was valid, would
6235 have code_addr == &_start. See the comment in frame_id_eq
6237 if (!frame_id_eq (get_stack_frame_id (frame
),
6238 ecs
->event_thread
->control
.step_stack_frame_id
)
6239 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6240 ecs
->event_thread
->control
.step_stack_frame_id
)
6241 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6243 || (ecs
->event_thread
->control
.step_start_function
6244 != find_pc_function (stop_pc
)))))
6246 CORE_ADDR real_stop_pc
;
6249 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6251 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6253 /* I presume that step_over_calls is only 0 when we're
6254 supposed to be stepping at the assembly language level
6255 ("stepi"). Just stop. */
6256 /* And this works the same backward as frontward. MVS */
6257 end_stepping_range (ecs
);
6261 /* Reverse stepping through solib trampolines. */
6263 if (execution_direction
== EXEC_REVERSE
6264 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6265 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6266 || (ecs
->stop_func_start
== 0
6267 && in_solib_dynsym_resolve_code (stop_pc
))))
6269 /* Any solib trampoline code can be handled in reverse
6270 by simply continuing to single-step. We have already
6271 executed the solib function (backwards), and a few
6272 steps will take us back through the trampoline to the
6278 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6280 /* We're doing a "next".
6282 Normal (forward) execution: set a breakpoint at the
6283 callee's return address (the address at which the caller
6286 Reverse (backward) execution. set the step-resume
6287 breakpoint at the start of the function that we just
6288 stepped into (backwards), and continue to there. When we
6289 get there, we'll need to single-step back to the caller. */
6291 if (execution_direction
== EXEC_REVERSE
)
6293 /* If we're already at the start of the function, we've either
6294 just stepped backward into a single instruction function,
6295 or stepped back out of a signal handler to the first instruction
6296 of the function. Just keep going, which will single-step back
6298 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6300 struct symtab_and_line sr_sal
;
6302 /* Normal function call return (static or dynamic). */
6304 sr_sal
.pc
= ecs
->stop_func_start
;
6305 sr_sal
.pspace
= get_frame_program_space (frame
);
6306 insert_step_resume_breakpoint_at_sal (gdbarch
,
6307 sr_sal
, null_frame_id
);
6311 insert_step_resume_breakpoint_at_caller (frame
);
6317 /* If we are in a function call trampoline (a stub between the
6318 calling routine and the real function), locate the real
6319 function. That's what tells us (a) whether we want to step
6320 into it at all, and (b) what prologue we want to run to the
6321 end of, if we do step into it. */
6322 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6323 if (real_stop_pc
== 0)
6324 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6325 if (real_stop_pc
!= 0)
6326 ecs
->stop_func_start
= real_stop_pc
;
6328 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6330 struct symtab_and_line sr_sal
;
6333 sr_sal
.pc
= ecs
->stop_func_start
;
6334 sr_sal
.pspace
= get_frame_program_space (frame
);
6336 insert_step_resume_breakpoint_at_sal (gdbarch
,
6337 sr_sal
, null_frame_id
);
6342 /* If we have line number information for the function we are
6343 thinking of stepping into and the function isn't on the skip
6346 If there are several symtabs at that PC (e.g. with include
6347 files), just want to know whether *any* of them have line
6348 numbers. find_pc_line handles this. */
6350 struct symtab_and_line tmp_sal
;
6352 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6353 if (tmp_sal
.line
!= 0
6354 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6357 if (execution_direction
== EXEC_REVERSE
)
6358 handle_step_into_function_backward (gdbarch
, ecs
);
6360 handle_step_into_function (gdbarch
, ecs
);
6365 /* If we have no line number and the step-stop-if-no-debug is
6366 set, we stop the step so that the user has a chance to switch
6367 in assembly mode. */
6368 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6369 && step_stop_if_no_debug
)
6371 end_stepping_range (ecs
);
6375 if (execution_direction
== EXEC_REVERSE
)
6377 /* If we're already at the start of the function, we've either just
6378 stepped backward into a single instruction function without line
6379 number info, or stepped back out of a signal handler to the first
6380 instruction of the function without line number info. Just keep
6381 going, which will single-step back to the caller. */
6382 if (ecs
->stop_func_start
!= stop_pc
)
6384 /* Set a breakpoint at callee's start address.
6385 From there we can step once and be back in the caller. */
6386 struct symtab_and_line sr_sal
;
6389 sr_sal
.pc
= ecs
->stop_func_start
;
6390 sr_sal
.pspace
= get_frame_program_space (frame
);
6391 insert_step_resume_breakpoint_at_sal (gdbarch
,
6392 sr_sal
, null_frame_id
);
6396 /* Set a breakpoint at callee's return address (the address
6397 at which the caller will resume). */
6398 insert_step_resume_breakpoint_at_caller (frame
);
6404 /* Reverse stepping through solib trampolines. */
6406 if (execution_direction
== EXEC_REVERSE
6407 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6409 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6410 || (ecs
->stop_func_start
== 0
6411 && in_solib_dynsym_resolve_code (stop_pc
)))
6413 /* Any solib trampoline code can be handled in reverse
6414 by simply continuing to single-step. We have already
6415 executed the solib function (backwards), and a few
6416 steps will take us back through the trampoline to the
6421 else if (in_solib_dynsym_resolve_code (stop_pc
))
6423 /* Stepped backward into the solib dynsym resolver.
6424 Set a breakpoint at its start and continue, then
6425 one more step will take us out. */
6426 struct symtab_and_line sr_sal
;
6429 sr_sal
.pc
= ecs
->stop_func_start
;
6430 sr_sal
.pspace
= get_frame_program_space (frame
);
6431 insert_step_resume_breakpoint_at_sal (gdbarch
,
6432 sr_sal
, null_frame_id
);
6438 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6440 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6441 the trampoline processing logic, however, there are some trampolines
6442 that have no names, so we should do trampoline handling first. */
6443 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6444 && ecs
->stop_func_name
== NULL
6445 && stop_pc_sal
.line
== 0)
6448 fprintf_unfiltered (gdb_stdlog
,
6449 "infrun: stepped into undebuggable function\n");
6451 /* The inferior just stepped into, or returned to, an
6452 undebuggable function (where there is no debugging information
6453 and no line number corresponding to the address where the
6454 inferior stopped). Since we want to skip this kind of code,
6455 we keep going until the inferior returns from this
6456 function - unless the user has asked us not to (via
6457 set step-mode) or we no longer know how to get back
6458 to the call site. */
6459 if (step_stop_if_no_debug
6460 || !frame_id_p (frame_unwind_caller_id (frame
)))
6462 /* If we have no line number and the step-stop-if-no-debug
6463 is set, we stop the step so that the user has a chance to
6464 switch in assembly mode. */
6465 end_stepping_range (ecs
);
6470 /* Set a breakpoint at callee's return address (the address
6471 at which the caller will resume). */
6472 insert_step_resume_breakpoint_at_caller (frame
);
6478 if (ecs
->event_thread
->control
.step_range_end
== 1)
6480 /* It is stepi or nexti. We always want to stop stepping after
6483 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6484 end_stepping_range (ecs
);
6488 if (stop_pc_sal
.line
== 0)
6490 /* We have no line number information. That means to stop
6491 stepping (does this always happen right after one instruction,
6492 when we do "s" in a function with no line numbers,
6493 or can this happen as a result of a return or longjmp?). */
6495 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6496 end_stepping_range (ecs
);
6500 /* Look for "calls" to inlined functions, part one. If the inline
6501 frame machinery detected some skipped call sites, we have entered
6502 a new inline function. */
6504 if (frame_id_eq (get_frame_id (get_current_frame ()),
6505 ecs
->event_thread
->control
.step_frame_id
)
6506 && inline_skipped_frames (ecs
->ptid
))
6508 struct symtab_and_line call_sal
;
6511 fprintf_unfiltered (gdb_stdlog
,
6512 "infrun: stepped into inlined function\n");
6514 find_frame_sal (get_current_frame (), &call_sal
);
6516 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6518 /* For "step", we're going to stop. But if the call site
6519 for this inlined function is on the same source line as
6520 we were previously stepping, go down into the function
6521 first. Otherwise stop at the call site. */
6523 if (call_sal
.line
== ecs
->event_thread
->current_line
6524 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6525 step_into_inline_frame (ecs
->ptid
);
6527 end_stepping_range (ecs
);
6532 /* For "next", we should stop at the call site if it is on a
6533 different source line. Otherwise continue through the
6534 inlined function. */
6535 if (call_sal
.line
== ecs
->event_thread
->current_line
6536 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6539 end_stepping_range (ecs
);
6544 /* Look for "calls" to inlined functions, part two. If we are still
6545 in the same real function we were stepping through, but we have
6546 to go further up to find the exact frame ID, we are stepping
6547 through a more inlined call beyond its call site. */
6549 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6550 && !frame_id_eq (get_frame_id (get_current_frame ()),
6551 ecs
->event_thread
->control
.step_frame_id
)
6552 && stepped_in_from (get_current_frame (),
6553 ecs
->event_thread
->control
.step_frame_id
))
6556 fprintf_unfiltered (gdb_stdlog
,
6557 "infrun: stepping through inlined function\n");
6559 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6562 end_stepping_range (ecs
);
6566 if ((stop_pc
== stop_pc_sal
.pc
)
6567 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6568 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6570 /* We are at the start of a different line. So stop. Note that
6571 we don't stop if we step into the middle of a different line.
6572 That is said to make things like for (;;) statements work
6575 fprintf_unfiltered (gdb_stdlog
,
6576 "infrun: stepped to a different line\n");
6577 end_stepping_range (ecs
);
6581 /* We aren't done stepping.
6583 Optimize by setting the stepping range to the line.
6584 (We might not be in the original line, but if we entered a
6585 new line in mid-statement, we continue stepping. This makes
6586 things like for(;;) statements work better.) */
6588 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
6589 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
6590 ecs
->event_thread
->control
.may_range_step
= 1;
6591 set_step_info (frame
, stop_pc_sal
);
6594 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
6598 /* In all-stop mode, if we're currently stepping but have stopped in
6599 some other thread, we may need to switch back to the stepped
6600 thread. Returns true we set the inferior running, false if we left
6601 it stopped (and the event needs further processing). */
6604 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
6606 if (!target_is_non_stop_p ())
6608 struct thread_info
*tp
;
6609 struct thread_info
*stepping_thread
;
6611 /* If any thread is blocked on some internal breakpoint, and we
6612 simply need to step over that breakpoint to get it going
6613 again, do that first. */
6615 /* However, if we see an event for the stepping thread, then we
6616 know all other threads have been moved past their breakpoints
6617 already. Let the caller check whether the step is finished,
6618 etc., before deciding to move it past a breakpoint. */
6619 if (ecs
->event_thread
->control
.step_range_end
!= 0)
6622 /* Check if the current thread is blocked on an incomplete
6623 step-over, interrupted by a random signal. */
6624 if (ecs
->event_thread
->control
.trap_expected
6625 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6629 fprintf_unfiltered (gdb_stdlog
,
6630 "infrun: need to finish step-over of [%s]\n",
6631 target_pid_to_str (ecs
->event_thread
->ptid
));
6637 /* Check if the current thread is blocked by a single-step
6638 breakpoint of another thread. */
6639 if (ecs
->hit_singlestep_breakpoint
)
6643 fprintf_unfiltered (gdb_stdlog
,
6644 "infrun: need to step [%s] over single-step "
6646 target_pid_to_str (ecs
->ptid
));
6652 /* If this thread needs yet another step-over (e.g., stepping
6653 through a delay slot), do it first before moving on to
6655 if (thread_still_needs_step_over (ecs
->event_thread
))
6659 fprintf_unfiltered (gdb_stdlog
,
6660 "infrun: thread [%s] still needs step-over\n",
6661 target_pid_to_str (ecs
->event_thread
->ptid
));
6667 /* If scheduler locking applies even if not stepping, there's no
6668 need to walk over threads. Above we've checked whether the
6669 current thread is stepping. If some other thread not the
6670 event thread is stepping, then it must be that scheduler
6671 locking is not in effect. */
6672 if (schedlock_applies (ecs
->event_thread
))
6675 /* Otherwise, we no longer expect a trap in the current thread.
6676 Clear the trap_expected flag before switching back -- this is
6677 what keep_going does as well, if we call it. */
6678 ecs
->event_thread
->control
.trap_expected
= 0;
6680 /* Likewise, clear the signal if it should not be passed. */
6681 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6682 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6684 /* Do all pending step-overs before actually proceeding with
6686 if (start_step_over ())
6688 prepare_to_wait (ecs
);
6692 /* Look for the stepping/nexting thread. */
6693 stepping_thread
= NULL
;
6695 ALL_NON_EXITED_THREADS (tp
)
6697 /* Ignore threads of processes the caller is not
6700 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
6703 /* When stepping over a breakpoint, we lock all threads
6704 except the one that needs to move past the breakpoint.
6705 If a non-event thread has this set, the "incomplete
6706 step-over" check above should have caught it earlier. */
6707 if (tp
->control
.trap_expected
)
6709 internal_error (__FILE__
, __LINE__
,
6710 "[%s] has inconsistent state: "
6711 "trap_expected=%d\n",
6712 target_pid_to_str (tp
->ptid
),
6713 tp
->control
.trap_expected
);
6716 /* Did we find the stepping thread? */
6717 if (tp
->control
.step_range_end
)
6719 /* Yep. There should only one though. */
6720 gdb_assert (stepping_thread
== NULL
);
6722 /* The event thread is handled at the top, before we
6724 gdb_assert (tp
!= ecs
->event_thread
);
6726 /* If some thread other than the event thread is
6727 stepping, then scheduler locking can't be in effect,
6728 otherwise we wouldn't have resumed the current event
6729 thread in the first place. */
6730 gdb_assert (!schedlock_applies (tp
));
6732 stepping_thread
= tp
;
6736 if (stepping_thread
!= NULL
)
6739 fprintf_unfiltered (gdb_stdlog
,
6740 "infrun: switching back to stepped thread\n");
6742 if (keep_going_stepped_thread (stepping_thread
))
6744 prepare_to_wait (ecs
);
6753 /* Set a previously stepped thread back to stepping. Returns true on
6754 success, false if the resume is not possible (e.g., the thread
6758 keep_going_stepped_thread (struct thread_info
*tp
)
6760 struct frame_info
*frame
;
6761 struct gdbarch
*gdbarch
;
6762 struct execution_control_state ecss
;
6763 struct execution_control_state
*ecs
= &ecss
;
6765 /* If the stepping thread exited, then don't try to switch back and
6766 resume it, which could fail in several different ways depending
6767 on the target. Instead, just keep going.
6769 We can find a stepping dead thread in the thread list in two
6772 - The target supports thread exit events, and when the target
6773 tries to delete the thread from the thread list, inferior_ptid
6774 pointed at the exiting thread. In such case, calling
6775 delete_thread does not really remove the thread from the list;
6776 instead, the thread is left listed, with 'exited' state.
6778 - The target's debug interface does not support thread exit
6779 events, and so we have no idea whatsoever if the previously
6780 stepping thread is still alive. For that reason, we need to
6781 synchronously query the target now. */
6783 if (is_exited (tp
->ptid
)
6784 || !target_thread_alive (tp
->ptid
))
6787 fprintf_unfiltered (gdb_stdlog
,
6788 "infrun: not resuming previously "
6789 "stepped thread, it has vanished\n");
6791 delete_thread (tp
->ptid
);
6796 fprintf_unfiltered (gdb_stdlog
,
6797 "infrun: resuming previously stepped thread\n");
6799 reset_ecs (ecs
, tp
);
6800 switch_to_thread (tp
->ptid
);
6802 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
6803 frame
= get_current_frame ();
6804 gdbarch
= get_frame_arch (frame
);
6806 /* If the PC of the thread we were trying to single-step has
6807 changed, then that thread has trapped or been signaled, but the
6808 event has not been reported to GDB yet. Re-poll the target
6809 looking for this particular thread's event (i.e. temporarily
6810 enable schedlock) by:
6812 - setting a break at the current PC
6813 - resuming that particular thread, only (by setting trap
6816 This prevents us continuously moving the single-step breakpoint
6817 forward, one instruction at a time, overstepping. */
6819 if (stop_pc
!= tp
->prev_pc
)
6824 fprintf_unfiltered (gdb_stdlog
,
6825 "infrun: expected thread advanced also (%s -> %s)\n",
6826 paddress (target_gdbarch (), tp
->prev_pc
),
6827 paddress (target_gdbarch (), stop_pc
));
6829 /* Clear the info of the previous step-over, as it's no longer
6830 valid (if the thread was trying to step over a breakpoint, it
6831 has already succeeded). It's what keep_going would do too,
6832 if we called it. Do this before trying to insert the sss
6833 breakpoint, otherwise if we were previously trying to step
6834 over this exact address in another thread, the breakpoint is
6836 clear_step_over_info ();
6837 tp
->control
.trap_expected
= 0;
6839 insert_single_step_breakpoint (get_frame_arch (frame
),
6840 get_frame_address_space (frame
),
6844 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
6845 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
6850 fprintf_unfiltered (gdb_stdlog
,
6851 "infrun: expected thread still hasn't advanced\n");
6853 keep_going_pass_signal (ecs
);
6858 /* Is thread TP in the middle of (software or hardware)
6859 single-stepping? (Note the result of this function must never be
6860 passed directly as target_resume's STEP parameter.) */
6863 currently_stepping (struct thread_info
*tp
)
6865 return ((tp
->control
.step_range_end
6866 && tp
->control
.step_resume_breakpoint
== NULL
)
6867 || tp
->control
.trap_expected
6868 || tp
->stepped_breakpoint
6869 || bpstat_should_step ());
6872 /* Inferior has stepped into a subroutine call with source code that
6873 we should not step over. Do step to the first line of code in
6877 handle_step_into_function (struct gdbarch
*gdbarch
,
6878 struct execution_control_state
*ecs
)
6880 struct compunit_symtab
*cust
;
6881 struct symtab_and_line stop_func_sal
, sr_sal
;
6883 fill_in_stop_func (gdbarch
, ecs
);
6885 cust
= find_pc_compunit_symtab (stop_pc
);
6886 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
6887 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
6888 ecs
->stop_func_start
);
6890 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6891 /* Use the step_resume_break to step until the end of the prologue,
6892 even if that involves jumps (as it seems to on the vax under
6894 /* If the prologue ends in the middle of a source line, continue to
6895 the end of that source line (if it is still within the function).
6896 Otherwise, just go to end of prologue. */
6897 if (stop_func_sal
.end
6898 && stop_func_sal
.pc
!= ecs
->stop_func_start
6899 && stop_func_sal
.end
< ecs
->stop_func_end
)
6900 ecs
->stop_func_start
= stop_func_sal
.end
;
6902 /* Architectures which require breakpoint adjustment might not be able
6903 to place a breakpoint at the computed address. If so, the test
6904 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
6905 ecs->stop_func_start to an address at which a breakpoint may be
6906 legitimately placed.
6908 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
6909 made, GDB will enter an infinite loop when stepping through
6910 optimized code consisting of VLIW instructions which contain
6911 subinstructions corresponding to different source lines. On
6912 FR-V, it's not permitted to place a breakpoint on any but the
6913 first subinstruction of a VLIW instruction. When a breakpoint is
6914 set, GDB will adjust the breakpoint address to the beginning of
6915 the VLIW instruction. Thus, we need to make the corresponding
6916 adjustment here when computing the stop address. */
6918 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
6920 ecs
->stop_func_start
6921 = gdbarch_adjust_breakpoint_address (gdbarch
,
6922 ecs
->stop_func_start
);
6925 if (ecs
->stop_func_start
== stop_pc
)
6927 /* We are already there: stop now. */
6928 end_stepping_range (ecs
);
6933 /* Put the step-breakpoint there and go until there. */
6934 init_sal (&sr_sal
); /* initialize to zeroes */
6935 sr_sal
.pc
= ecs
->stop_func_start
;
6936 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
6937 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
6939 /* Do not specify what the fp should be when we stop since on
6940 some machines the prologue is where the new fp value is
6942 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
6944 /* And make sure stepping stops right away then. */
6945 ecs
->event_thread
->control
.step_range_end
6946 = ecs
->event_thread
->control
.step_range_start
;
6951 /* Inferior has stepped backward into a subroutine call with source
6952 code that we should not step over. Do step to the beginning of the
6953 last line of code in it. */
6956 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
6957 struct execution_control_state
*ecs
)
6959 struct compunit_symtab
*cust
;
6960 struct symtab_and_line stop_func_sal
;
6962 fill_in_stop_func (gdbarch
, ecs
);
6964 cust
= find_pc_compunit_symtab (stop_pc
);
6965 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
6966 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
6967 ecs
->stop_func_start
);
6969 stop_func_sal
= find_pc_line (stop_pc
, 0);
6971 /* OK, we're just going to keep stepping here. */
6972 if (stop_func_sal
.pc
== stop_pc
)
6974 /* We're there already. Just stop stepping now. */
6975 end_stepping_range (ecs
);
6979 /* Else just reset the step range and keep going.
6980 No step-resume breakpoint, they don't work for
6981 epilogues, which can have multiple entry paths. */
6982 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
6983 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
6989 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
6990 This is used to both functions and to skip over code. */
6993 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
6994 struct symtab_and_line sr_sal
,
6995 struct frame_id sr_id
,
6996 enum bptype sr_type
)
6998 /* There should never be more than one step-resume or longjmp-resume
6999 breakpoint per thread, so we should never be setting a new
7000 step_resume_breakpoint when one is already active. */
7001 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7002 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7005 fprintf_unfiltered (gdb_stdlog
,
7006 "infrun: inserting step-resume breakpoint at %s\n",
7007 paddress (gdbarch
, sr_sal
.pc
));
7009 inferior_thread ()->control
.step_resume_breakpoint
7010 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
7014 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7015 struct symtab_and_line sr_sal
,
7016 struct frame_id sr_id
)
7018 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7023 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7024 This is used to skip a potential signal handler.
7026 This is called with the interrupted function's frame. The signal
7027 handler, when it returns, will resume the interrupted function at
7031 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7033 struct symtab_and_line sr_sal
;
7034 struct gdbarch
*gdbarch
;
7036 gdb_assert (return_frame
!= NULL
);
7037 init_sal (&sr_sal
); /* initialize to zeros */
7039 gdbarch
= get_frame_arch (return_frame
);
7040 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7041 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7042 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7044 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7045 get_stack_frame_id (return_frame
),
7049 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7050 is used to skip a function after stepping into it (for "next" or if
7051 the called function has no debugging information).
7053 The current function has almost always been reached by single
7054 stepping a call or return instruction. NEXT_FRAME belongs to the
7055 current function, and the breakpoint will be set at the caller's
7058 This is a separate function rather than reusing
7059 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7060 get_prev_frame, which may stop prematurely (see the implementation
7061 of frame_unwind_caller_id for an example). */
7064 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7066 struct symtab_and_line sr_sal
;
7067 struct gdbarch
*gdbarch
;
7069 /* We shouldn't have gotten here if we don't know where the call site
7071 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7073 init_sal (&sr_sal
); /* initialize to zeros */
7075 gdbarch
= frame_unwind_caller_arch (next_frame
);
7076 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7077 frame_unwind_caller_pc (next_frame
));
7078 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7079 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7081 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7082 frame_unwind_caller_id (next_frame
));
7085 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7086 new breakpoint at the target of a jmp_buf. The handling of
7087 longjmp-resume uses the same mechanisms used for handling
7088 "step-resume" breakpoints. */
7091 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7093 /* There should never be more than one longjmp-resume breakpoint per
7094 thread, so we should never be setting a new
7095 longjmp_resume_breakpoint when one is already active. */
7096 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7099 fprintf_unfiltered (gdb_stdlog
,
7100 "infrun: inserting longjmp-resume breakpoint at %s\n",
7101 paddress (gdbarch
, pc
));
7103 inferior_thread ()->control
.exception_resume_breakpoint
=
7104 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
7107 /* Insert an exception resume breakpoint. TP is the thread throwing
7108 the exception. The block B is the block of the unwinder debug hook
7109 function. FRAME is the frame corresponding to the call to this
7110 function. SYM is the symbol of the function argument holding the
7111 target PC of the exception. */
7114 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7115 const struct block
*b
,
7116 struct frame_info
*frame
,
7121 struct symbol
*vsym
;
7122 struct value
*value
;
7124 struct breakpoint
*bp
;
7126 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
,
7128 value
= read_var_value (vsym
, frame
);
7129 /* If the value was optimized out, revert to the old behavior. */
7130 if (! value_optimized_out (value
))
7132 handler
= value_as_address (value
);
7135 fprintf_unfiltered (gdb_stdlog
,
7136 "infrun: exception resume at %lx\n",
7137 (unsigned long) handler
);
7139 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7140 handler
, bp_exception_resume
);
7142 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7145 bp
->thread
= tp
->num
;
7146 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7149 CATCH (e
, RETURN_MASK_ERROR
)
7151 /* We want to ignore errors here. */
7156 /* A helper for check_exception_resume that sets an
7157 exception-breakpoint based on a SystemTap probe. */
7160 insert_exception_resume_from_probe (struct thread_info
*tp
,
7161 const struct bound_probe
*probe
,
7162 struct frame_info
*frame
)
7164 struct value
*arg_value
;
7166 struct breakpoint
*bp
;
7168 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7172 handler
= value_as_address (arg_value
);
7175 fprintf_unfiltered (gdb_stdlog
,
7176 "infrun: exception resume at %s\n",
7177 paddress (get_objfile_arch (probe
->objfile
),
7180 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7181 handler
, bp_exception_resume
);
7182 bp
->thread
= tp
->num
;
7183 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7186 /* This is called when an exception has been intercepted. Check to
7187 see whether the exception's destination is of interest, and if so,
7188 set an exception resume breakpoint there. */
7191 check_exception_resume (struct execution_control_state
*ecs
,
7192 struct frame_info
*frame
)
7194 struct bound_probe probe
;
7195 struct symbol
*func
;
7197 /* First see if this exception unwinding breakpoint was set via a
7198 SystemTap probe point. If so, the probe has two arguments: the
7199 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7200 set a breakpoint there. */
7201 probe
= find_probe_by_pc (get_frame_pc (frame
));
7204 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7208 func
= get_frame_function (frame
);
7214 const struct block
*b
;
7215 struct block_iterator iter
;
7219 /* The exception breakpoint is a thread-specific breakpoint on
7220 the unwinder's debug hook, declared as:
7222 void _Unwind_DebugHook (void *cfa, void *handler);
7224 The CFA argument indicates the frame to which control is
7225 about to be transferred. HANDLER is the destination PC.
7227 We ignore the CFA and set a temporary breakpoint at HANDLER.
7228 This is not extremely efficient but it avoids issues in gdb
7229 with computing the DWARF CFA, and it also works even in weird
7230 cases such as throwing an exception from inside a signal
7233 b
= SYMBOL_BLOCK_VALUE (func
);
7234 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7236 if (!SYMBOL_IS_ARGUMENT (sym
))
7243 insert_exception_resume_breakpoint (ecs
->event_thread
,
7249 CATCH (e
, RETURN_MASK_ERROR
)
7256 stop_waiting (struct execution_control_state
*ecs
)
7259 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7261 clear_step_over_info ();
7263 /* Let callers know we don't want to wait for the inferior anymore. */
7264 ecs
->wait_some_more
= 0;
7266 /* If all-stop, but the target is always in non-stop mode, stop all
7267 threads now that we're presenting the stop to the user. */
7268 if (!non_stop
&& target_is_non_stop_p ())
7269 stop_all_threads ();
7272 /* Like keep_going, but passes the signal to the inferior, even if the
7273 signal is set to nopass. */
7276 keep_going_pass_signal (struct execution_control_state
*ecs
)
7278 /* Make sure normal_stop is called if we get a QUIT handled before
7280 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
7282 gdb_assert (ptid_equal (ecs
->event_thread
->ptid
, inferior_ptid
));
7283 gdb_assert (!ecs
->event_thread
->resumed
);
7285 /* Save the pc before execution, to compare with pc after stop. */
7286 ecs
->event_thread
->prev_pc
7287 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
7289 if (ecs
->event_thread
->control
.trap_expected
)
7291 struct thread_info
*tp
= ecs
->event_thread
;
7294 fprintf_unfiltered (gdb_stdlog
,
7295 "infrun: %s has trap_expected set, "
7296 "resuming to collect trap\n",
7297 target_pid_to_str (tp
->ptid
));
7299 /* We haven't yet gotten our trap, and either: intercepted a
7300 non-signal event (e.g., a fork); or took a signal which we
7301 are supposed to pass through to the inferior. Simply
7303 discard_cleanups (old_cleanups
);
7304 resume (ecs
->event_thread
->suspend
.stop_signal
);
7306 else if (step_over_info_valid_p ())
7308 /* Another thread is stepping over a breakpoint in-line. If
7309 this thread needs a step-over too, queue the request. In
7310 either case, this resume must be deferred for later. */
7311 struct thread_info
*tp
= ecs
->event_thread
;
7313 if (ecs
->hit_singlestep_breakpoint
7314 || thread_still_needs_step_over (tp
))
7317 fprintf_unfiltered (gdb_stdlog
,
7318 "infrun: step-over already in progress: "
7319 "step-over for %s deferred\n",
7320 target_pid_to_str (tp
->ptid
));
7321 thread_step_over_chain_enqueue (tp
);
7326 fprintf_unfiltered (gdb_stdlog
,
7327 "infrun: step-over in progress: "
7328 "resume of %s deferred\n",
7329 target_pid_to_str (tp
->ptid
));
7332 discard_cleanups (old_cleanups
);
7336 struct regcache
*regcache
= get_current_regcache ();
7339 enum step_over_what step_what
;
7341 /* Either the trap was not expected, but we are continuing
7342 anyway (if we got a signal, the user asked it be passed to
7345 We got our expected trap, but decided we should resume from
7348 We're going to run this baby now!
7350 Note that insert_breakpoints won't try to re-insert
7351 already inserted breakpoints. Therefore, we don't
7352 care if breakpoints were already inserted, or not. */
7354 /* If we need to step over a breakpoint, and we're not using
7355 displaced stepping to do so, insert all breakpoints
7356 (watchpoints, etc.) but the one we're stepping over, step one
7357 instruction, and then re-insert the breakpoint when that step
7360 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7362 remove_bp
= (ecs
->hit_singlestep_breakpoint
7363 || (step_what
& STEP_OVER_BREAKPOINT
));
7364 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7366 /* We can't use displaced stepping if we need to step past a
7367 watchpoint. The instruction copied to the scratch pad would
7368 still trigger the watchpoint. */
7371 || !use_displaced_stepping (get_regcache_arch (regcache
))))
7373 set_step_over_info (get_regcache_aspace (regcache
),
7374 regcache_read_pc (regcache
), remove_wps
);
7376 else if (remove_wps
)
7377 set_step_over_info (NULL
, 0, remove_wps
);
7379 /* If we now need to do an in-line step-over, we need to stop
7380 all other threads. Note this must be done before
7381 insert_breakpoints below, because that removes the breakpoint
7382 we're about to step over, otherwise other threads could miss
7384 if (step_over_info_valid_p () && target_is_non_stop_p ())
7385 stop_all_threads ();
7387 /* Stop stepping if inserting breakpoints fails. */
7390 insert_breakpoints ();
7392 CATCH (e
, RETURN_MASK_ERROR
)
7394 exception_print (gdb_stderr
, e
);
7396 discard_cleanups (old_cleanups
);
7401 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7403 discard_cleanups (old_cleanups
);
7404 resume (ecs
->event_thread
->suspend
.stop_signal
);
7407 prepare_to_wait (ecs
);
7410 /* Called when we should continue running the inferior, because the
7411 current event doesn't cause a user visible stop. This does the
7412 resuming part; waiting for the next event is done elsewhere. */
7415 keep_going (struct execution_control_state
*ecs
)
7417 if (ecs
->event_thread
->control
.trap_expected
7418 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7419 ecs
->event_thread
->control
.trap_expected
= 0;
7421 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7422 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7423 keep_going_pass_signal (ecs
);
7426 /* This function normally comes after a resume, before
7427 handle_inferior_event exits. It takes care of any last bits of
7428 housekeeping, and sets the all-important wait_some_more flag. */
7431 prepare_to_wait (struct execution_control_state
*ecs
)
7434 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7436 /* This is the old end of the while loop. Let everybody know we
7437 want to wait for the inferior some more and get called again
7439 ecs
->wait_some_more
= 1;
7442 /* We are done with the step range of a step/next/si/ni command.
7443 Called once for each n of a "step n" operation. */
7446 end_stepping_range (struct execution_control_state
*ecs
)
7448 ecs
->event_thread
->control
.stop_step
= 1;
7452 /* Several print_*_reason functions to print why the inferior has stopped.
7453 We always print something when the inferior exits, or receives a signal.
7454 The rest of the cases are dealt with later on in normal_stop and
7455 print_it_typical. Ideally there should be a call to one of these
7456 print_*_reason functions functions from handle_inferior_event each time
7457 stop_waiting is called.
7459 Note that we don't call these directly, instead we delegate that to
7460 the interpreters, through observers. Interpreters then call these
7461 with whatever uiout is right. */
7464 print_end_stepping_range_reason (struct ui_out
*uiout
)
7466 /* For CLI-like interpreters, print nothing. */
7468 if (ui_out_is_mi_like_p (uiout
))
7470 ui_out_field_string (uiout
, "reason",
7471 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7476 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7478 annotate_signalled ();
7479 if (ui_out_is_mi_like_p (uiout
))
7481 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7482 ui_out_text (uiout
, "\nProgram terminated with signal ");
7483 annotate_signal_name ();
7484 ui_out_field_string (uiout
, "signal-name",
7485 gdb_signal_to_name (siggnal
));
7486 annotate_signal_name_end ();
7487 ui_out_text (uiout
, ", ");
7488 annotate_signal_string ();
7489 ui_out_field_string (uiout
, "signal-meaning",
7490 gdb_signal_to_string (siggnal
));
7491 annotate_signal_string_end ();
7492 ui_out_text (uiout
, ".\n");
7493 ui_out_text (uiout
, "The program no longer exists.\n");
7497 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7499 struct inferior
*inf
= current_inferior ();
7500 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
7502 annotate_exited (exitstatus
);
7505 if (ui_out_is_mi_like_p (uiout
))
7506 ui_out_field_string (uiout
, "reason",
7507 async_reason_lookup (EXEC_ASYNC_EXITED
));
7508 ui_out_text (uiout
, "[Inferior ");
7509 ui_out_text (uiout
, plongest (inf
->num
));
7510 ui_out_text (uiout
, " (");
7511 ui_out_text (uiout
, pidstr
);
7512 ui_out_text (uiout
, ") exited with code ");
7513 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
7514 ui_out_text (uiout
, "]\n");
7518 if (ui_out_is_mi_like_p (uiout
))
7520 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7521 ui_out_text (uiout
, "[Inferior ");
7522 ui_out_text (uiout
, plongest (inf
->num
));
7523 ui_out_text (uiout
, " (");
7524 ui_out_text (uiout
, pidstr
);
7525 ui_out_text (uiout
, ") exited normally]\n");
7530 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7534 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
7536 struct thread_info
*t
= inferior_thread ();
7538 ui_out_text (uiout
, "\n[");
7539 ui_out_field_string (uiout
, "thread-name",
7540 target_pid_to_str (t
->ptid
));
7541 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
7542 ui_out_text (uiout
, " stopped");
7546 ui_out_text (uiout
, "\nProgram received signal ");
7547 annotate_signal_name ();
7548 if (ui_out_is_mi_like_p (uiout
))
7550 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
7551 ui_out_field_string (uiout
, "signal-name",
7552 gdb_signal_to_name (siggnal
));
7553 annotate_signal_name_end ();
7554 ui_out_text (uiout
, ", ");
7555 annotate_signal_string ();
7556 ui_out_field_string (uiout
, "signal-meaning",
7557 gdb_signal_to_string (siggnal
));
7558 annotate_signal_string_end ();
7560 ui_out_text (uiout
, ".\n");
7564 print_no_history_reason (struct ui_out
*uiout
)
7566 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
7569 /* Print current location without a level number, if we have changed
7570 functions or hit a breakpoint. Print source line if we have one.
7571 bpstat_print contains the logic deciding in detail what to print,
7572 based on the event(s) that just occurred. */
7575 print_stop_event (struct target_waitstatus
*ws
)
7578 enum print_what source_flag
;
7579 int do_frame_printing
= 1;
7580 struct thread_info
*tp
= inferior_thread ();
7582 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
7586 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
7587 should) carry around the function and does (or should) use
7588 that when doing a frame comparison. */
7589 if (tp
->control
.stop_step
7590 && frame_id_eq (tp
->control
.step_frame_id
,
7591 get_frame_id (get_current_frame ()))
7592 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
7594 /* Finished step, just print source line. */
7595 source_flag
= SRC_LINE
;
7599 /* Print location and source line. */
7600 source_flag
= SRC_AND_LOC
;
7603 case PRINT_SRC_AND_LOC
:
7604 /* Print location and source line. */
7605 source_flag
= SRC_AND_LOC
;
7607 case PRINT_SRC_ONLY
:
7608 source_flag
= SRC_LINE
;
7611 /* Something bogus. */
7612 source_flag
= SRC_LINE
;
7613 do_frame_printing
= 0;
7616 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
7619 /* The behavior of this routine with respect to the source
7621 SRC_LINE: Print only source line
7622 LOCATION: Print only location
7623 SRC_AND_LOC: Print location and source line. */
7624 if (do_frame_printing
)
7625 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
7627 /* Display the auto-display expressions. */
7631 /* Here to return control to GDB when the inferior stops for real.
7632 Print appropriate messages, remove breakpoints, give terminal our modes.
7634 STOP_PRINT_FRAME nonzero means print the executing frame
7635 (pc, function, args, file, line number and line text).
7636 BREAKPOINTS_FAILED nonzero means stop was due to error
7637 attempting to insert breakpoints. */
7642 struct target_waitstatus last
;
7644 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
7647 get_last_target_status (&last_ptid
, &last
);
7649 /* If an exception is thrown from this point on, make sure to
7650 propagate GDB's knowledge of the executing state to the
7651 frontend/user running state. A QUIT is an easy exception to see
7652 here, so do this before any filtered output. */
7654 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
7655 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
7656 || last
.kind
== TARGET_WAITKIND_EXITED
)
7658 /* On some targets, we may still have live threads in the
7659 inferior when we get a process exit event. E.g., for
7660 "checkpoint", when the current checkpoint/fork exits,
7661 linux-fork.c automatically switches to another fork from
7662 within target_mourn_inferior. */
7663 if (!ptid_equal (inferior_ptid
, null_ptid
))
7665 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
7666 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
7669 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
7670 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
7672 /* As we're presenting a stop, and potentially removing breakpoints,
7673 update the thread list so we can tell whether there are threads
7674 running on the target. With target remote, for example, we can
7675 only learn about new threads when we explicitly update the thread
7676 list. Do this before notifying the interpreters about signal
7677 stops, end of stepping ranges, etc., so that the "new thread"
7678 output is emitted before e.g., "Program received signal FOO",
7679 instead of after. */
7680 update_thread_list ();
7682 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
7683 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
7685 /* As with the notification of thread events, we want to delay
7686 notifying the user that we've switched thread context until
7687 the inferior actually stops.
7689 There's no point in saying anything if the inferior has exited.
7690 Note that SIGNALLED here means "exited with a signal", not
7691 "received a signal".
7693 Also skip saying anything in non-stop mode. In that mode, as we
7694 don't want GDB to switch threads behind the user's back, to avoid
7695 races where the user is typing a command to apply to thread x,
7696 but GDB switches to thread y before the user finishes entering
7697 the command, fetch_inferior_event installs a cleanup to restore
7698 the current thread back to the thread the user had selected right
7699 after this event is handled, so we're not really switching, only
7700 informing of a stop. */
7702 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
7703 && target_has_execution
7704 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
7705 && last
.kind
!= TARGET_WAITKIND_EXITED
7706 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
7708 target_terminal_ours_for_output ();
7709 printf_filtered (_("[Switching to %s]\n"),
7710 target_pid_to_str (inferior_ptid
));
7711 annotate_thread_changed ();
7712 previous_inferior_ptid
= inferior_ptid
;
7715 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
7717 gdb_assert (sync_execution
|| !target_can_async_p ());
7719 target_terminal_ours_for_output ();
7720 printf_filtered (_("No unwaited-for children left.\n"));
7723 /* Note: this depends on the update_thread_list call above. */
7724 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
7726 if (remove_breakpoints ())
7728 target_terminal_ours_for_output ();
7729 printf_filtered (_("Cannot remove breakpoints because "
7730 "program is no longer writable.\nFurther "
7731 "execution is probably impossible.\n"));
7735 /* If an auto-display called a function and that got a signal,
7736 delete that auto-display to avoid an infinite recursion. */
7738 if (stopped_by_random_signal
)
7739 disable_current_display ();
7741 /* Notify observers if we finished a "step"-like command, etc. */
7742 if (target_has_execution
7743 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
7744 && last
.kind
!= TARGET_WAITKIND_EXITED
7745 && inferior_thread ()->control
.stop_step
)
7747 /* But not if in the middle of doing a "step n" operation for
7749 if (inferior_thread ()->step_multi
)
7752 observer_notify_end_stepping_range ();
7755 target_terminal_ours ();
7756 async_enable_stdin ();
7758 /* Set the current source location. This will also happen if we
7759 display the frame below, but the current SAL will be incorrect
7760 during a user hook-stop function. */
7761 if (has_stack_frames () && !stop_stack_dummy
)
7762 set_current_sal_from_frame (get_current_frame ());
7764 /* Let the user/frontend see the threads as stopped, but defer to
7765 call_function_by_hand if the thread finished an infcall
7766 successfully. We may be e.g., evaluating a breakpoint condition.
7767 In that case, the thread had state THREAD_RUNNING before the
7768 infcall, and shall remain marked running, all without informing
7769 the user/frontend about state transition changes. */
7770 if (target_has_execution
7771 && inferior_thread ()->control
.in_infcall
7772 && stop_stack_dummy
== STOP_STACK_DUMMY
)
7773 discard_cleanups (old_chain
);
7775 do_cleanups (old_chain
);
7777 /* Look up the hook_stop and run it (CLI internally handles problem
7778 of stop_command's pre-hook not existing). */
7780 catch_errors (hook_stop_stub
, stop_command
,
7781 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
7783 if (!has_stack_frames ())
7786 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
7787 || last
.kind
== TARGET_WAITKIND_EXITED
)
7790 /* Select innermost stack frame - i.e., current frame is frame 0,
7791 and current location is based on that.
7792 Don't do this on return from a stack dummy routine,
7793 or if the program has exited. */
7795 if (!stop_stack_dummy
)
7797 select_frame (get_current_frame ());
7799 /* If --batch-silent is enabled then there's no need to print the current
7800 source location, and to try risks causing an error message about
7801 missing source files. */
7802 if (stop_print_frame
&& !batch_silent
)
7803 print_stop_event (&last
);
7806 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
7808 /* Pop the empty frame that contains the stack dummy.
7809 This also restores inferior state prior to the call
7810 (struct infcall_suspend_state). */
7811 struct frame_info
*frame
= get_current_frame ();
7813 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
7815 /* frame_pop() calls reinit_frame_cache as the last thing it
7816 does which means there's currently no selected frame. We
7817 don't need to re-establish a selected frame if the dummy call
7818 returns normally, that will be done by
7819 restore_infcall_control_state. However, we do have to handle
7820 the case where the dummy call is returning after being
7821 stopped (e.g. the dummy call previously hit a breakpoint).
7822 We can't know which case we have so just always re-establish
7823 a selected frame here. */
7824 select_frame (get_current_frame ());
7828 annotate_stopped ();
7830 /* Suppress the stop observer if we're in the middle of:
7832 - a step n (n > 1), as there still more steps to be done.
7834 - a "finish" command, as the observer will be called in
7835 finish_command_continuation, so it can include the inferior
7836 function's return value.
7838 - calling an inferior function, as we pretend we inferior didn't
7839 run at all. The return value of the call is handled by the
7840 expression evaluator, through call_function_by_hand. */
7842 if (!target_has_execution
7843 || last
.kind
== TARGET_WAITKIND_SIGNALLED
7844 || last
.kind
== TARGET_WAITKIND_EXITED
7845 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
7846 || (!(inferior_thread ()->step_multi
7847 && inferior_thread ()->control
.stop_step
)
7848 && !(inferior_thread ()->control
.stop_bpstat
7849 && inferior_thread ()->control
.proceed_to_finish
)
7850 && !inferior_thread ()->control
.in_infcall
))
7852 if (!ptid_equal (inferior_ptid
, null_ptid
))
7853 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
7856 observer_notify_normal_stop (NULL
, stop_print_frame
);
7859 if (target_has_execution
)
7861 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
7862 && last
.kind
!= TARGET_WAITKIND_EXITED
)
7863 /* Delete the breakpoint we stopped at, if it wants to be deleted.
7864 Delete any breakpoint that is to be deleted at the next stop. */
7865 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
7868 /* Try to get rid of automatically added inferiors that are no
7869 longer needed. Keeping those around slows down things linearly.
7870 Note that this never removes the current inferior. */
7875 hook_stop_stub (void *cmd
)
7877 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
7882 signal_stop_state (int signo
)
7884 return signal_stop
[signo
];
7888 signal_print_state (int signo
)
7890 return signal_print
[signo
];
7894 signal_pass_state (int signo
)
7896 return signal_program
[signo
];
7900 signal_cache_update (int signo
)
7904 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
7905 signal_cache_update (signo
);
7910 signal_pass
[signo
] = (signal_stop
[signo
] == 0
7911 && signal_print
[signo
] == 0
7912 && signal_program
[signo
] == 1
7913 && signal_catch
[signo
] == 0);
7917 signal_stop_update (int signo
, int state
)
7919 int ret
= signal_stop
[signo
];
7921 signal_stop
[signo
] = state
;
7922 signal_cache_update (signo
);
7927 signal_print_update (int signo
, int state
)
7929 int ret
= signal_print
[signo
];
7931 signal_print
[signo
] = state
;
7932 signal_cache_update (signo
);
7937 signal_pass_update (int signo
, int state
)
7939 int ret
= signal_program
[signo
];
7941 signal_program
[signo
] = state
;
7942 signal_cache_update (signo
);
7946 /* Update the global 'signal_catch' from INFO and notify the
7950 signal_catch_update (const unsigned int *info
)
7954 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
7955 signal_catch
[i
] = info
[i
] > 0;
7956 signal_cache_update (-1);
7957 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
7961 sig_print_header (void)
7963 printf_filtered (_("Signal Stop\tPrint\tPass "
7964 "to program\tDescription\n"));
7968 sig_print_info (enum gdb_signal oursig
)
7970 const char *name
= gdb_signal_to_name (oursig
);
7971 int name_padding
= 13 - strlen (name
);
7973 if (name_padding
<= 0)
7976 printf_filtered ("%s", name
);
7977 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
7978 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
7979 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
7980 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
7981 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
7984 /* Specify how various signals in the inferior should be handled. */
7987 handle_command (char *args
, int from_tty
)
7990 int digits
, wordlen
;
7991 int sigfirst
, signum
, siglast
;
7992 enum gdb_signal oursig
;
7995 unsigned char *sigs
;
7996 struct cleanup
*old_chain
;
8000 error_no_arg (_("signal to handle"));
8003 /* Allocate and zero an array of flags for which signals to handle. */
8005 nsigs
= (int) GDB_SIGNAL_LAST
;
8006 sigs
= (unsigned char *) alloca (nsigs
);
8007 memset (sigs
, 0, nsigs
);
8009 /* Break the command line up into args. */
8011 argv
= gdb_buildargv (args
);
8012 old_chain
= make_cleanup_freeargv (argv
);
8014 /* Walk through the args, looking for signal oursigs, signal names, and
8015 actions. Signal numbers and signal names may be interspersed with
8016 actions, with the actions being performed for all signals cumulatively
8017 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8019 while (*argv
!= NULL
)
8021 wordlen
= strlen (*argv
);
8022 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
8026 sigfirst
= siglast
= -1;
8028 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
8030 /* Apply action to all signals except those used by the
8031 debugger. Silently skip those. */
8034 siglast
= nsigs
- 1;
8036 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
8038 SET_SIGS (nsigs
, sigs
, signal_stop
);
8039 SET_SIGS (nsigs
, sigs
, signal_print
);
8041 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
8043 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8045 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
8047 SET_SIGS (nsigs
, sigs
, signal_print
);
8049 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
8051 SET_SIGS (nsigs
, sigs
, signal_program
);
8053 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
8055 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8057 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
8059 SET_SIGS (nsigs
, sigs
, signal_program
);
8061 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
8063 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8064 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8066 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
8068 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8070 else if (digits
> 0)
8072 /* It is numeric. The numeric signal refers to our own
8073 internal signal numbering from target.h, not to host/target
8074 signal number. This is a feature; users really should be
8075 using symbolic names anyway, and the common ones like
8076 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8078 sigfirst
= siglast
= (int)
8079 gdb_signal_from_command (atoi (*argv
));
8080 if ((*argv
)[digits
] == '-')
8083 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
8085 if (sigfirst
> siglast
)
8087 /* Bet he didn't figure we'd think of this case... */
8095 oursig
= gdb_signal_from_name (*argv
);
8096 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8098 sigfirst
= siglast
= (int) oursig
;
8102 /* Not a number and not a recognized flag word => complain. */
8103 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
8107 /* If any signal numbers or symbol names were found, set flags for
8108 which signals to apply actions to. */
8110 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8112 switch ((enum gdb_signal
) signum
)
8114 case GDB_SIGNAL_TRAP
:
8115 case GDB_SIGNAL_INT
:
8116 if (!allsigs
&& !sigs
[signum
])
8118 if (query (_("%s is used by the debugger.\n\
8119 Are you sure you want to change it? "),
8120 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8126 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8127 gdb_flush (gdb_stdout
);
8132 case GDB_SIGNAL_DEFAULT
:
8133 case GDB_SIGNAL_UNKNOWN
:
8134 /* Make sure that "all" doesn't print these. */
8145 for (signum
= 0; signum
< nsigs
; signum
++)
8148 signal_cache_update (-1);
8149 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8150 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8154 /* Show the results. */
8155 sig_print_header ();
8156 for (; signum
< nsigs
; signum
++)
8158 sig_print_info ((enum gdb_signal
) signum
);
8164 do_cleanups (old_chain
);
8167 /* Complete the "handle" command. */
8169 static VEC (char_ptr
) *
8170 handle_completer (struct cmd_list_element
*ignore
,
8171 const char *text
, const char *word
)
8173 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
8174 static const char * const keywords
[] =
8188 vec_signals
= signal_completer (ignore
, text
, word
);
8189 vec_keywords
= complete_on_enum (keywords
, word
, word
);
8191 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
8192 VEC_free (char_ptr
, vec_signals
);
8193 VEC_free (char_ptr
, vec_keywords
);
8198 gdb_signal_from_command (int num
)
8200 if (num
>= 1 && num
<= 15)
8201 return (enum gdb_signal
) num
;
8202 error (_("Only signals 1-15 are valid as numeric signals.\n\
8203 Use \"info signals\" for a list of symbolic signals."));
8206 /* Print current contents of the tables set by the handle command.
8207 It is possible we should just be printing signals actually used
8208 by the current target (but for things to work right when switching
8209 targets, all signals should be in the signal tables). */
8212 signals_info (char *signum_exp
, int from_tty
)
8214 enum gdb_signal oursig
;
8216 sig_print_header ();
8220 /* First see if this is a symbol name. */
8221 oursig
= gdb_signal_from_name (signum_exp
);
8222 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8224 /* No, try numeric. */
8226 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8228 sig_print_info (oursig
);
8232 printf_filtered ("\n");
8233 /* These ugly casts brought to you by the native VAX compiler. */
8234 for (oursig
= GDB_SIGNAL_FIRST
;
8235 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8236 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8240 if (oursig
!= GDB_SIGNAL_UNKNOWN
8241 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8242 sig_print_info (oursig
);
8245 printf_filtered (_("\nUse the \"handle\" command "
8246 "to change these tables.\n"));
8249 /* Check if it makes sense to read $_siginfo from the current thread
8250 at this point. If not, throw an error. */
8253 validate_siginfo_access (void)
8255 /* No current inferior, no siginfo. */
8256 if (ptid_equal (inferior_ptid
, null_ptid
))
8257 error (_("No thread selected."));
8259 /* Don't try to read from a dead thread. */
8260 if (is_exited (inferior_ptid
))
8261 error (_("The current thread has terminated"));
8263 /* ... or from a spinning thread. */
8264 if (is_running (inferior_ptid
))
8265 error (_("Selected thread is running."));
8268 /* The $_siginfo convenience variable is a bit special. We don't know
8269 for sure the type of the value until we actually have a chance to
8270 fetch the data. The type can change depending on gdbarch, so it is
8271 also dependent on which thread you have selected.
8273 1. making $_siginfo be an internalvar that creates a new value on
8276 2. making the value of $_siginfo be an lval_computed value. */
8278 /* This function implements the lval_computed support for reading a
8282 siginfo_value_read (struct value
*v
)
8284 LONGEST transferred
;
8286 validate_siginfo_access ();
8289 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8291 value_contents_all_raw (v
),
8293 TYPE_LENGTH (value_type (v
)));
8295 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8296 error (_("Unable to read siginfo"));
8299 /* This function implements the lval_computed support for writing a
8303 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8305 LONGEST transferred
;
8307 validate_siginfo_access ();
8309 transferred
= target_write (¤t_target
,
8310 TARGET_OBJECT_SIGNAL_INFO
,
8312 value_contents_all_raw (fromval
),
8314 TYPE_LENGTH (value_type (fromval
)));
8316 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8317 error (_("Unable to write siginfo"));
8320 static const struct lval_funcs siginfo_value_funcs
=
8326 /* Return a new value with the correct type for the siginfo object of
8327 the current thread using architecture GDBARCH. Return a void value
8328 if there's no object available. */
8330 static struct value
*
8331 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8334 if (target_has_stack
8335 && !ptid_equal (inferior_ptid
, null_ptid
)
8336 && gdbarch_get_siginfo_type_p (gdbarch
))
8338 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8340 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8343 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8347 /* infcall_suspend_state contains state about the program itself like its
8348 registers and any signal it received when it last stopped.
8349 This state must be restored regardless of how the inferior function call
8350 ends (either successfully, or after it hits a breakpoint or signal)
8351 if the program is to properly continue where it left off. */
8353 struct infcall_suspend_state
8355 struct thread_suspend_state thread_suspend
;
8359 struct regcache
*registers
;
8361 /* Format of SIGINFO_DATA or NULL if it is not present. */
8362 struct gdbarch
*siginfo_gdbarch
;
8364 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8365 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8366 content would be invalid. */
8367 gdb_byte
*siginfo_data
;
8370 struct infcall_suspend_state
*
8371 save_infcall_suspend_state (void)
8373 struct infcall_suspend_state
*inf_state
;
8374 struct thread_info
*tp
= inferior_thread ();
8375 struct regcache
*regcache
= get_current_regcache ();
8376 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8377 gdb_byte
*siginfo_data
= NULL
;
8379 if (gdbarch_get_siginfo_type_p (gdbarch
))
8381 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8382 size_t len
= TYPE_LENGTH (type
);
8383 struct cleanup
*back_to
;
8385 siginfo_data
= xmalloc (len
);
8386 back_to
= make_cleanup (xfree
, siginfo_data
);
8388 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8389 siginfo_data
, 0, len
) == len
)
8390 discard_cleanups (back_to
);
8393 /* Errors ignored. */
8394 do_cleanups (back_to
);
8395 siginfo_data
= NULL
;
8399 inf_state
= XCNEW (struct infcall_suspend_state
);
8403 inf_state
->siginfo_gdbarch
= gdbarch
;
8404 inf_state
->siginfo_data
= siginfo_data
;
8407 inf_state
->thread_suspend
= tp
->suspend
;
8409 /* run_inferior_call will not use the signal due to its `proceed' call with
8410 GDB_SIGNAL_0 anyway. */
8411 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8413 inf_state
->stop_pc
= stop_pc
;
8415 inf_state
->registers
= regcache_dup (regcache
);
8420 /* Restore inferior session state to INF_STATE. */
8423 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8425 struct thread_info
*tp
= inferior_thread ();
8426 struct regcache
*regcache
= get_current_regcache ();
8427 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8429 tp
->suspend
= inf_state
->thread_suspend
;
8431 stop_pc
= inf_state
->stop_pc
;
8433 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8435 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8437 /* Errors ignored. */
8438 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8439 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8442 /* The inferior can be gone if the user types "print exit(0)"
8443 (and perhaps other times). */
8444 if (target_has_execution
)
8445 /* NB: The register write goes through to the target. */
8446 regcache_cpy (regcache
, inf_state
->registers
);
8448 discard_infcall_suspend_state (inf_state
);
8452 do_restore_infcall_suspend_state_cleanup (void *state
)
8454 restore_infcall_suspend_state (state
);
8458 make_cleanup_restore_infcall_suspend_state
8459 (struct infcall_suspend_state
*inf_state
)
8461 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
8465 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8467 regcache_xfree (inf_state
->registers
);
8468 xfree (inf_state
->siginfo_data
);
8473 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8475 return inf_state
->registers
;
8478 /* infcall_control_state contains state regarding gdb's control of the
8479 inferior itself like stepping control. It also contains session state like
8480 the user's currently selected frame. */
8482 struct infcall_control_state
8484 struct thread_control_state thread_control
;
8485 struct inferior_control_state inferior_control
;
8488 enum stop_stack_kind stop_stack_dummy
;
8489 int stopped_by_random_signal
;
8490 int stop_after_trap
;
8492 /* ID if the selected frame when the inferior function call was made. */
8493 struct frame_id selected_frame_id
;
8496 /* Save all of the information associated with the inferior<==>gdb
8499 struct infcall_control_state
*
8500 save_infcall_control_state (void)
8502 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
8503 struct thread_info
*tp
= inferior_thread ();
8504 struct inferior
*inf
= current_inferior ();
8506 inf_status
->thread_control
= tp
->control
;
8507 inf_status
->inferior_control
= inf
->control
;
8509 tp
->control
.step_resume_breakpoint
= NULL
;
8510 tp
->control
.exception_resume_breakpoint
= NULL
;
8512 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
8513 chain. If caller's caller is walking the chain, they'll be happier if we
8514 hand them back the original chain when restore_infcall_control_state is
8516 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
8519 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
8520 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
8521 inf_status
->stop_after_trap
= stop_after_trap
;
8523 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
8529 restore_selected_frame (void *args
)
8531 struct frame_id
*fid
= (struct frame_id
*) args
;
8532 struct frame_info
*frame
;
8534 frame
= frame_find_by_id (*fid
);
8536 /* If inf_status->selected_frame_id is NULL, there was no previously
8540 warning (_("Unable to restore previously selected frame."));
8544 select_frame (frame
);
8549 /* Restore inferior session state to INF_STATUS. */
8552 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
8554 struct thread_info
*tp
= inferior_thread ();
8555 struct inferior
*inf
= current_inferior ();
8557 if (tp
->control
.step_resume_breakpoint
)
8558 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
8560 if (tp
->control
.exception_resume_breakpoint
)
8561 tp
->control
.exception_resume_breakpoint
->disposition
8562 = disp_del_at_next_stop
;
8564 /* Handle the bpstat_copy of the chain. */
8565 bpstat_clear (&tp
->control
.stop_bpstat
);
8567 tp
->control
= inf_status
->thread_control
;
8568 inf
->control
= inf_status
->inferior_control
;
8571 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
8572 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
8573 stop_after_trap
= inf_status
->stop_after_trap
;
8575 if (target_has_stack
)
8577 /* The point of catch_errors is that if the stack is clobbered,
8578 walking the stack might encounter a garbage pointer and
8579 error() trying to dereference it. */
8581 (restore_selected_frame
, &inf_status
->selected_frame_id
,
8582 "Unable to restore previously selected frame:\n",
8583 RETURN_MASK_ERROR
) == 0)
8584 /* Error in restoring the selected frame. Select the innermost
8586 select_frame (get_current_frame ());
8593 do_restore_infcall_control_state_cleanup (void *sts
)
8595 restore_infcall_control_state (sts
);
8599 make_cleanup_restore_infcall_control_state
8600 (struct infcall_control_state
*inf_status
)
8602 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
8606 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
8608 if (inf_status
->thread_control
.step_resume_breakpoint
)
8609 inf_status
->thread_control
.step_resume_breakpoint
->disposition
8610 = disp_del_at_next_stop
;
8612 if (inf_status
->thread_control
.exception_resume_breakpoint
)
8613 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
8614 = disp_del_at_next_stop
;
8616 /* See save_infcall_control_state for info on stop_bpstat. */
8617 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
8622 /* restore_inferior_ptid() will be used by the cleanup machinery
8623 to restore the inferior_ptid value saved in a call to
8624 save_inferior_ptid(). */
8627 restore_inferior_ptid (void *arg
)
8629 ptid_t
*saved_ptid_ptr
= arg
;
8631 inferior_ptid
= *saved_ptid_ptr
;
8635 /* Save the value of inferior_ptid so that it may be restored by a
8636 later call to do_cleanups(). Returns the struct cleanup pointer
8637 needed for later doing the cleanup. */
8640 save_inferior_ptid (void)
8642 ptid_t
*saved_ptid_ptr
;
8644 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
8645 *saved_ptid_ptr
= inferior_ptid
;
8646 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
8652 clear_exit_convenience_vars (void)
8654 clear_internalvar (lookup_internalvar ("_exitsignal"));
8655 clear_internalvar (lookup_internalvar ("_exitcode"));
8659 /* User interface for reverse debugging:
8660 Set exec-direction / show exec-direction commands
8661 (returns error unless target implements to_set_exec_direction method). */
8663 int execution_direction
= EXEC_FORWARD
;
8664 static const char exec_forward
[] = "forward";
8665 static const char exec_reverse
[] = "reverse";
8666 static const char *exec_direction
= exec_forward
;
8667 static const char *const exec_direction_names
[] = {
8674 set_exec_direction_func (char *args
, int from_tty
,
8675 struct cmd_list_element
*cmd
)
8677 if (target_can_execute_reverse
)
8679 if (!strcmp (exec_direction
, exec_forward
))
8680 execution_direction
= EXEC_FORWARD
;
8681 else if (!strcmp (exec_direction
, exec_reverse
))
8682 execution_direction
= EXEC_REVERSE
;
8686 exec_direction
= exec_forward
;
8687 error (_("Target does not support this operation."));
8692 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
8693 struct cmd_list_element
*cmd
, const char *value
)
8695 switch (execution_direction
) {
8697 fprintf_filtered (out
, _("Forward.\n"));
8700 fprintf_filtered (out
, _("Reverse.\n"));
8703 internal_error (__FILE__
, __LINE__
,
8704 _("bogus execution_direction value: %d"),
8705 (int) execution_direction
);
8710 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
8711 struct cmd_list_element
*c
, const char *value
)
8713 fprintf_filtered (file
, _("Resuming the execution of threads "
8714 "of all processes is %s.\n"), value
);
8717 /* Implementation of `siginfo' variable. */
8719 static const struct internalvar_funcs siginfo_funcs
=
8726 /* Callback for infrun's target events source. This is marked when a
8727 thread has a pending status to process. */
8730 infrun_async_inferior_event_handler (gdb_client_data data
)
8732 /* If the target is closed while this event source is marked, we
8733 will reach here without execution, or a target to call
8734 target_wait on, which is an error. Instead of tracking whether
8735 the target has been popped already, or whether we do have threads
8736 with pending statutes, simply ignore the event. */
8737 if (!target_is_async_p ())
8740 inferior_event_handler (INF_REG_EVENT
, NULL
);
8744 _initialize_infrun (void)
8748 struct cmd_list_element
*c
;
8750 /* Register extra event sources in the event loop. */
8751 infrun_async_inferior_event_token
8752 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
8754 add_info ("signals", signals_info
, _("\
8755 What debugger does when program gets various signals.\n\
8756 Specify a signal as argument to print info on that signal only."));
8757 add_info_alias ("handle", "signals", 0);
8759 c
= add_com ("handle", class_run
, handle_command
, _("\
8760 Specify how to handle signals.\n\
8761 Usage: handle SIGNAL [ACTIONS]\n\
8762 Args are signals and actions to apply to those signals.\n\
8763 If no actions are specified, the current settings for the specified signals\n\
8764 will be displayed instead.\n\
8766 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
8767 from 1-15 are allowed for compatibility with old versions of GDB.\n\
8768 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
8769 The special arg \"all\" is recognized to mean all signals except those\n\
8770 used by the debugger, typically SIGTRAP and SIGINT.\n\
8772 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
8773 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
8774 Stop means reenter debugger if this signal happens (implies print).\n\
8775 Print means print a message if this signal happens.\n\
8776 Pass means let program see this signal; otherwise program doesn't know.\n\
8777 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
8778 Pass and Stop may be combined.\n\
8780 Multiple signals may be specified. Signal numbers and signal names\n\
8781 may be interspersed with actions, with the actions being performed for\n\
8782 all signals cumulatively specified."));
8783 set_cmd_completer (c
, handle_completer
);
8786 stop_command
= add_cmd ("stop", class_obscure
,
8787 not_just_help_class_command
, _("\
8788 There is no `stop' command, but you can set a hook on `stop'.\n\
8789 This allows you to set a list of commands to be run each time execution\n\
8790 of the program stops."), &cmdlist
);
8792 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
8793 Set inferior debugging."), _("\
8794 Show inferior debugging."), _("\
8795 When non-zero, inferior specific debugging is enabled."),
8798 &setdebuglist
, &showdebuglist
);
8800 add_setshow_boolean_cmd ("displaced", class_maintenance
,
8801 &debug_displaced
, _("\
8802 Set displaced stepping debugging."), _("\
8803 Show displaced stepping debugging."), _("\
8804 When non-zero, displaced stepping specific debugging is enabled."),
8806 show_debug_displaced
,
8807 &setdebuglist
, &showdebuglist
);
8809 add_setshow_boolean_cmd ("non-stop", no_class
,
8811 Set whether gdb controls the inferior in non-stop mode."), _("\
8812 Show whether gdb controls the inferior in non-stop mode."), _("\
8813 When debugging a multi-threaded program and this setting is\n\
8814 off (the default, also called all-stop mode), when one thread stops\n\
8815 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
8816 all other threads in the program while you interact with the thread of\n\
8817 interest. When you continue or step a thread, you can allow the other\n\
8818 threads to run, or have them remain stopped, but while you inspect any\n\
8819 thread's state, all threads stop.\n\
8821 In non-stop mode, when one thread stops, other threads can continue\n\
8822 to run freely. You'll be able to step each thread independently,\n\
8823 leave it stopped or free to run as needed."),
8829 numsigs
= (int) GDB_SIGNAL_LAST
;
8830 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
8831 signal_print
= (unsigned char *)
8832 xmalloc (sizeof (signal_print
[0]) * numsigs
);
8833 signal_program
= (unsigned char *)
8834 xmalloc (sizeof (signal_program
[0]) * numsigs
);
8835 signal_catch
= (unsigned char *)
8836 xmalloc (sizeof (signal_catch
[0]) * numsigs
);
8837 signal_pass
= (unsigned char *)
8838 xmalloc (sizeof (signal_pass
[0]) * numsigs
);
8839 for (i
= 0; i
< numsigs
; i
++)
8842 signal_print
[i
] = 1;
8843 signal_program
[i
] = 1;
8844 signal_catch
[i
] = 0;
8847 /* Signals caused by debugger's own actions should not be given to
8848 the program afterwards.
8850 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
8851 explicitly specifies that it should be delivered to the target
8852 program. Typically, that would occur when a user is debugging a
8853 target monitor on a simulator: the target monitor sets a
8854 breakpoint; the simulator encounters this breakpoint and halts
8855 the simulation handing control to GDB; GDB, noting that the stop
8856 address doesn't map to any known breakpoint, returns control back
8857 to the simulator; the simulator then delivers the hardware
8858 equivalent of a GDB_SIGNAL_TRAP to the program being
8860 signal_program
[GDB_SIGNAL_TRAP
] = 0;
8861 signal_program
[GDB_SIGNAL_INT
] = 0;
8863 /* Signals that are not errors should not normally enter the debugger. */
8864 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
8865 signal_print
[GDB_SIGNAL_ALRM
] = 0;
8866 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
8867 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
8868 signal_stop
[GDB_SIGNAL_PROF
] = 0;
8869 signal_print
[GDB_SIGNAL_PROF
] = 0;
8870 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
8871 signal_print
[GDB_SIGNAL_CHLD
] = 0;
8872 signal_stop
[GDB_SIGNAL_IO
] = 0;
8873 signal_print
[GDB_SIGNAL_IO
] = 0;
8874 signal_stop
[GDB_SIGNAL_POLL
] = 0;
8875 signal_print
[GDB_SIGNAL_POLL
] = 0;
8876 signal_stop
[GDB_SIGNAL_URG
] = 0;
8877 signal_print
[GDB_SIGNAL_URG
] = 0;
8878 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
8879 signal_print
[GDB_SIGNAL_WINCH
] = 0;
8880 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
8881 signal_print
[GDB_SIGNAL_PRIO
] = 0;
8883 /* These signals are used internally by user-level thread
8884 implementations. (See signal(5) on Solaris.) Like the above
8885 signals, a healthy program receives and handles them as part of
8886 its normal operation. */
8887 signal_stop
[GDB_SIGNAL_LWP
] = 0;
8888 signal_print
[GDB_SIGNAL_LWP
] = 0;
8889 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
8890 signal_print
[GDB_SIGNAL_WAITING
] = 0;
8891 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
8892 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
8894 /* Update cached state. */
8895 signal_cache_update (-1);
8897 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
8898 &stop_on_solib_events
, _("\
8899 Set stopping for shared library events."), _("\
8900 Show stopping for shared library events."), _("\
8901 If nonzero, gdb will give control to the user when the dynamic linker\n\
8902 notifies gdb of shared library events. The most common event of interest\n\
8903 to the user would be loading/unloading of a new library."),
8904 set_stop_on_solib_events
,
8905 show_stop_on_solib_events
,
8906 &setlist
, &showlist
);
8908 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
8909 follow_fork_mode_kind_names
,
8910 &follow_fork_mode_string
, _("\
8911 Set debugger response to a program call of fork or vfork."), _("\
8912 Show debugger response to a program call of fork or vfork."), _("\
8913 A fork or vfork creates a new process. follow-fork-mode can be:\n\
8914 parent - the original process is debugged after a fork\n\
8915 child - the new process is debugged after a fork\n\
8916 The unfollowed process will continue to run.\n\
8917 By default, the debugger will follow the parent process."),
8919 show_follow_fork_mode_string
,
8920 &setlist
, &showlist
);
8922 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
8923 follow_exec_mode_names
,
8924 &follow_exec_mode_string
, _("\
8925 Set debugger response to a program call of exec."), _("\
8926 Show debugger response to a program call of exec."), _("\
8927 An exec call replaces the program image of a process.\n\
8929 follow-exec-mode can be:\n\
8931 new - the debugger creates a new inferior and rebinds the process\n\
8932 to this new inferior. The program the process was running before\n\
8933 the exec call can be restarted afterwards by restarting the original\n\
8936 same - the debugger keeps the process bound to the same inferior.\n\
8937 The new executable image replaces the previous executable loaded in\n\
8938 the inferior. Restarting the inferior after the exec call restarts\n\
8939 the executable the process was running after the exec call.\n\
8941 By default, the debugger will use the same inferior."),
8943 show_follow_exec_mode_string
,
8944 &setlist
, &showlist
);
8946 add_setshow_enum_cmd ("scheduler-locking", class_run
,
8947 scheduler_enums
, &scheduler_mode
, _("\
8948 Set mode for locking scheduler during execution."), _("\
8949 Show mode for locking scheduler during execution."), _("\
8950 off == no locking (threads may preempt at any time)\n\
8951 on == full locking (no thread except the current thread may run)\n\
8952 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
8953 In this mode, other threads may run during other commands."),
8954 set_schedlock_func
, /* traps on target vector */
8955 show_scheduler_mode
,
8956 &setlist
, &showlist
);
8958 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
8959 Set mode for resuming threads of all processes."), _("\
8960 Show mode for resuming threads of all processes."), _("\
8961 When on, execution commands (such as 'continue' or 'next') resume all\n\
8962 threads of all processes. When off (which is the default), execution\n\
8963 commands only resume the threads of the current process. The set of\n\
8964 threads that are resumed is further refined by the scheduler-locking\n\
8965 mode (see help set scheduler-locking)."),
8967 show_schedule_multiple
,
8968 &setlist
, &showlist
);
8970 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
8971 Set mode of the step operation."), _("\
8972 Show mode of the step operation."), _("\
8973 When set, doing a step over a function without debug line information\n\
8974 will stop at the first instruction of that function. Otherwise, the\n\
8975 function is skipped and the step command stops at a different source line."),
8977 show_step_stop_if_no_debug
,
8978 &setlist
, &showlist
);
8980 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
8981 &can_use_displaced_stepping
, _("\
8982 Set debugger's willingness to use displaced stepping."), _("\
8983 Show debugger's willingness to use displaced stepping."), _("\
8984 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
8985 supported by the target architecture. If off, gdb will not use displaced\n\
8986 stepping to step over breakpoints, even if such is supported by the target\n\
8987 architecture. If auto (which is the default), gdb will use displaced stepping\n\
8988 if the target architecture supports it and non-stop mode is active, but will not\n\
8989 use it in all-stop mode (see help set non-stop)."),
8991 show_can_use_displaced_stepping
,
8992 &setlist
, &showlist
);
8994 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
8995 &exec_direction
, _("Set direction of execution.\n\
8996 Options are 'forward' or 'reverse'."),
8997 _("Show direction of execution (forward/reverse)."),
8998 _("Tells gdb whether to execute forward or backward."),
8999 set_exec_direction_func
, show_exec_direction_func
,
9000 &setlist
, &showlist
);
9002 /* Set/show detach-on-fork: user-settable mode. */
9004 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9005 Set whether gdb will detach the child of a fork."), _("\
9006 Show whether gdb will detach the child of a fork."), _("\
9007 Tells gdb whether to detach the child of a fork."),
9008 NULL
, NULL
, &setlist
, &showlist
);
9010 /* Set/show disable address space randomization mode. */
9012 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9013 &disable_randomization
, _("\
9014 Set disabling of debuggee's virtual address space randomization."), _("\
9015 Show disabling of debuggee's virtual address space randomization."), _("\
9016 When this mode is on (which is the default), randomization of the virtual\n\
9017 address space is disabled. Standalone programs run with the randomization\n\
9018 enabled by default on some platforms."),
9019 &set_disable_randomization
,
9020 &show_disable_randomization
,
9021 &setlist
, &showlist
);
9023 /* ptid initializations */
9024 inferior_ptid
= null_ptid
;
9025 target_last_wait_ptid
= minus_one_ptid
;
9027 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
9028 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
9029 observer_attach_thread_exit (infrun_thread_thread_exit
);
9030 observer_attach_inferior_exit (infrun_inferior_exit
);
9032 /* Explicitly create without lookup, since that tries to create a
9033 value with a void typed value, and when we get here, gdbarch
9034 isn't initialized yet. At this point, we're quite sure there
9035 isn't another convenience variable of the same name. */
9036 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9038 add_setshow_boolean_cmd ("observer", no_class
,
9039 &observer_mode_1
, _("\
9040 Set whether gdb controls the inferior in observer mode."), _("\
9041 Show whether gdb controls the inferior in observer mode."), _("\
9042 In observer mode, GDB can get data from the inferior, but not\n\
9043 affect its execution. Registers and memory may not be changed,\n\
9044 breakpoints may not be set, and the program cannot be interrupted\n\