1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2016 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"
65 #include "thread-fsm.h"
66 #include "common/enum-flags.h"
68 /* Prototypes for local functions */
70 static void signals_info (char *, int);
72 static void handle_command (char *, int);
74 static void sig_print_info (enum gdb_signal
);
76 static void sig_print_header (void);
78 static void resume_cleanups (void *);
80 static int hook_stop_stub (void *);
82 static int restore_selected_frame (void *);
84 static int follow_fork (void);
86 static int follow_fork_inferior (int follow_child
, int detach_fork
);
88 static void follow_inferior_reset_breakpoints (void);
90 static void set_schedlock_func (char *args
, int from_tty
,
91 struct cmd_list_element
*c
);
93 static int currently_stepping (struct thread_info
*tp
);
95 void _initialize_infrun (void);
97 void nullify_last_target_wait_ptid (void);
99 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
101 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
103 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
105 static int maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
);
107 /* Asynchronous signal handler registered as event loop source for
108 when we have pending events ready to be passed to the core. */
109 static struct async_event_handler
*infrun_async_inferior_event_token
;
111 /* Stores whether infrun_async was previously enabled or disabled.
112 Starts off as -1, indicating "never enabled/disabled". */
113 static int infrun_is_async
= -1;
118 infrun_async (int enable
)
120 if (infrun_is_async
!= enable
)
122 infrun_is_async
= enable
;
125 fprintf_unfiltered (gdb_stdlog
,
126 "infrun: infrun_async(%d)\n",
130 mark_async_event_handler (infrun_async_inferior_event_token
);
132 clear_async_event_handler (infrun_async_inferior_event_token
);
139 mark_infrun_async_event_handler (void)
141 mark_async_event_handler (infrun_async_inferior_event_token
);
144 /* When set, stop the 'step' command if we enter a function which has
145 no line number information. The normal behavior is that we step
146 over such function. */
147 int step_stop_if_no_debug
= 0;
149 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
150 struct cmd_list_element
*c
, const char *value
)
152 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
155 /* proceed and normal_stop use this to notify the user when the
156 inferior stopped in a different thread than it had been running
159 static ptid_t previous_inferior_ptid
;
161 /* If set (default for legacy reasons), when following a fork, GDB
162 will detach from one of the fork branches, child or parent.
163 Exactly which branch is detached depends on 'set follow-fork-mode'
166 static int detach_fork
= 1;
168 int debug_displaced
= 0;
170 show_debug_displaced (struct ui_file
*file
, int from_tty
,
171 struct cmd_list_element
*c
, const char *value
)
173 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
176 unsigned int debug_infrun
= 0;
178 show_debug_infrun (struct ui_file
*file
, int from_tty
,
179 struct cmd_list_element
*c
, const char *value
)
181 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
185 /* Support for disabling address space randomization. */
187 int disable_randomization
= 1;
190 show_disable_randomization (struct ui_file
*file
, int from_tty
,
191 struct cmd_list_element
*c
, const char *value
)
193 if (target_supports_disable_randomization ())
194 fprintf_filtered (file
,
195 _("Disabling randomization of debuggee's "
196 "virtual address space is %s.\n"),
199 fputs_filtered (_("Disabling randomization of debuggee's "
200 "virtual address space is unsupported on\n"
201 "this platform.\n"), file
);
205 set_disable_randomization (char *args
, int from_tty
,
206 struct cmd_list_element
*c
)
208 if (!target_supports_disable_randomization ())
209 error (_("Disabling randomization of debuggee's "
210 "virtual address space is unsupported on\n"
214 /* User interface for non-stop mode. */
217 static int non_stop_1
= 0;
220 set_non_stop (char *args
, int from_tty
,
221 struct cmd_list_element
*c
)
223 if (target_has_execution
)
225 non_stop_1
= non_stop
;
226 error (_("Cannot change this setting while the inferior is running."));
229 non_stop
= non_stop_1
;
233 show_non_stop (struct ui_file
*file
, int from_tty
,
234 struct cmd_list_element
*c
, const char *value
)
236 fprintf_filtered (file
,
237 _("Controlling the inferior in non-stop mode is %s.\n"),
241 /* "Observer mode" is somewhat like a more extreme version of
242 non-stop, in which all GDB operations that might affect the
243 target's execution have been disabled. */
245 int observer_mode
= 0;
246 static int observer_mode_1
= 0;
249 set_observer_mode (char *args
, int from_tty
,
250 struct cmd_list_element
*c
)
252 if (target_has_execution
)
254 observer_mode_1
= observer_mode
;
255 error (_("Cannot change this setting while the inferior is running."));
258 observer_mode
= observer_mode_1
;
260 may_write_registers
= !observer_mode
;
261 may_write_memory
= !observer_mode
;
262 may_insert_breakpoints
= !observer_mode
;
263 may_insert_tracepoints
= !observer_mode
;
264 /* We can insert fast tracepoints in or out of observer mode,
265 but enable them if we're going into this mode. */
267 may_insert_fast_tracepoints
= 1;
268 may_stop
= !observer_mode
;
269 update_target_permissions ();
271 /* Going *into* observer mode we must force non-stop, then
272 going out we leave it that way. */
275 pagination_enabled
= 0;
276 non_stop
= non_stop_1
= 1;
280 printf_filtered (_("Observer mode is now %s.\n"),
281 (observer_mode
? "on" : "off"));
285 show_observer_mode (struct ui_file
*file
, int from_tty
,
286 struct cmd_list_element
*c
, const char *value
)
288 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
291 /* This updates the value of observer mode based on changes in
292 permissions. Note that we are deliberately ignoring the values of
293 may-write-registers and may-write-memory, since the user may have
294 reason to enable these during a session, for instance to turn on a
295 debugging-related global. */
298 update_observer_mode (void)
302 newval
= (!may_insert_breakpoints
303 && !may_insert_tracepoints
304 && may_insert_fast_tracepoints
308 /* Let the user know if things change. */
309 if (newval
!= observer_mode
)
310 printf_filtered (_("Observer mode is now %s.\n"),
311 (newval
? "on" : "off"));
313 observer_mode
= observer_mode_1
= newval
;
316 /* Tables of how to react to signals; the user sets them. */
318 static unsigned char *signal_stop
;
319 static unsigned char *signal_print
;
320 static unsigned char *signal_program
;
322 /* Table of signals that are registered with "catch signal". A
323 non-zero entry indicates that the signal is caught by some "catch
324 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
326 static unsigned char *signal_catch
;
328 /* Table of signals that the target may silently handle.
329 This is automatically determined from the flags above,
330 and simply cached here. */
331 static unsigned char *signal_pass
;
333 #define SET_SIGS(nsigs,sigs,flags) \
335 int signum = (nsigs); \
336 while (signum-- > 0) \
337 if ((sigs)[signum]) \
338 (flags)[signum] = 1; \
341 #define UNSET_SIGS(nsigs,sigs,flags) \
343 int signum = (nsigs); \
344 while (signum-- > 0) \
345 if ((sigs)[signum]) \
346 (flags)[signum] = 0; \
349 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
350 this function is to avoid exporting `signal_program'. */
353 update_signals_program_target (void)
355 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
358 /* Value to pass to target_resume() to cause all threads to resume. */
360 #define RESUME_ALL minus_one_ptid
362 /* Command list pointer for the "stop" placeholder. */
364 static struct cmd_list_element
*stop_command
;
366 /* Nonzero if we want to give control to the user when we're notified
367 of shared library events by the dynamic linker. */
368 int stop_on_solib_events
;
370 /* Enable or disable optional shared library event breakpoints
371 as appropriate when the above flag is changed. */
374 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
376 update_solib_breakpoints ();
380 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
381 struct cmd_list_element
*c
, const char *value
)
383 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
387 /* Nonzero after stop if current stack frame should be printed. */
389 static int stop_print_frame
;
391 /* This is a cached copy of the pid/waitstatus of the last event
392 returned by target_wait()/deprecated_target_wait_hook(). This
393 information is returned by get_last_target_status(). */
394 static ptid_t target_last_wait_ptid
;
395 static struct target_waitstatus target_last_waitstatus
;
397 static void context_switch (ptid_t ptid
);
399 void init_thread_stepping_state (struct thread_info
*tss
);
401 static const char follow_fork_mode_child
[] = "child";
402 static const char follow_fork_mode_parent
[] = "parent";
404 static const char *const follow_fork_mode_kind_names
[] = {
405 follow_fork_mode_child
,
406 follow_fork_mode_parent
,
410 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
412 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
413 struct cmd_list_element
*c
, const char *value
)
415 fprintf_filtered (file
,
416 _("Debugger response to a program "
417 "call of fork or vfork is \"%s\".\n"),
422 /* Handle changes to the inferior list based on the type of fork,
423 which process is being followed, and whether the other process
424 should be detached. On entry inferior_ptid must be the ptid of
425 the fork parent. At return inferior_ptid is the ptid of the
426 followed inferior. */
429 follow_fork_inferior (int follow_child
, int detach_fork
)
432 ptid_t parent_ptid
, child_ptid
;
434 has_vforked
= (inferior_thread ()->pending_follow
.kind
435 == TARGET_WAITKIND_VFORKED
);
436 parent_ptid
= inferior_ptid
;
437 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
440 && !non_stop
/* Non-stop always resumes both branches. */
441 && current_ui
->prompt_state
== PROMPT_BLOCKED
442 && !(follow_child
|| detach_fork
|| sched_multi
))
444 /* The parent stays blocked inside the vfork syscall until the
445 child execs or exits. If we don't let the child run, then
446 the parent stays blocked. If we're telling the parent to run
447 in the foreground, the user will not be able to ctrl-c to get
448 back the terminal, effectively hanging the debug session. */
449 fprintf_filtered (gdb_stderr
, _("\
450 Can not resume the parent process over vfork in the foreground while\n\
451 holding the child stopped. Try \"set detach-on-fork\" or \
452 \"set schedule-multiple\".\n"));
453 /* FIXME output string > 80 columns. */
459 /* Detach new forked process? */
462 /* Before detaching from the child, remove all breakpoints
463 from it. If we forked, then this has already been taken
464 care of by infrun.c. If we vforked however, any
465 breakpoint inserted in the parent is visible in the
466 child, even those added while stopped in a vfork
467 catchpoint. This will remove the breakpoints from the
468 parent also, but they'll be reinserted below. */
471 /* Keep breakpoints list in sync. */
472 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
475 if (info_verbose
|| debug_infrun
)
477 /* Ensure that we have a process ptid. */
478 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
480 target_terminal_ours_for_output ();
481 fprintf_filtered (gdb_stdlog
,
482 _("Detaching after %s from child %s.\n"),
483 has_vforked
? "vfork" : "fork",
484 target_pid_to_str (process_ptid
));
489 struct inferior
*parent_inf
, *child_inf
;
490 struct cleanup
*old_chain
;
492 /* Add process to GDB's tables. */
493 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
495 parent_inf
= current_inferior ();
496 child_inf
->attach_flag
= parent_inf
->attach_flag
;
497 copy_terminal_info (child_inf
, parent_inf
);
498 child_inf
->gdbarch
= parent_inf
->gdbarch
;
499 copy_inferior_target_desc_info (child_inf
, parent_inf
);
501 old_chain
= save_inferior_ptid ();
502 save_current_program_space ();
504 inferior_ptid
= child_ptid
;
505 add_thread (inferior_ptid
);
506 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
508 /* If this is a vfork child, then the address-space is
509 shared with the parent. */
512 child_inf
->pspace
= parent_inf
->pspace
;
513 child_inf
->aspace
= parent_inf
->aspace
;
515 /* The parent will be frozen until the child is done
516 with the shared region. Keep track of the
518 child_inf
->vfork_parent
= parent_inf
;
519 child_inf
->pending_detach
= 0;
520 parent_inf
->vfork_child
= child_inf
;
521 parent_inf
->pending_detach
= 0;
525 child_inf
->aspace
= new_address_space ();
526 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
527 child_inf
->removable
= 1;
528 set_current_program_space (child_inf
->pspace
);
529 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
531 /* Let the shared library layer (e.g., solib-svr4) learn
532 about this new process, relocate the cloned exec, pull
533 in shared libraries, and install the solib event
534 breakpoint. If a "cloned-VM" event was propagated
535 better throughout the core, this wouldn't be
537 solib_create_inferior_hook (0);
540 do_cleanups (old_chain
);
545 struct inferior
*parent_inf
;
547 parent_inf
= current_inferior ();
549 /* If we detached from the child, then we have to be careful
550 to not insert breakpoints in the parent until the child
551 is done with the shared memory region. However, if we're
552 staying attached to the child, then we can and should
553 insert breakpoints, so that we can debug it. A
554 subsequent child exec or exit is enough to know when does
555 the child stops using the parent's address space. */
556 parent_inf
->waiting_for_vfork_done
= detach_fork
;
557 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
562 /* Follow the child. */
563 struct inferior
*parent_inf
, *child_inf
;
564 struct program_space
*parent_pspace
;
566 if (info_verbose
|| debug_infrun
)
568 target_terminal_ours_for_output ();
569 fprintf_filtered (gdb_stdlog
,
570 _("Attaching after %s %s to child %s.\n"),
571 target_pid_to_str (parent_ptid
),
572 has_vforked
? "vfork" : "fork",
573 target_pid_to_str (child_ptid
));
576 /* Add the new inferior first, so that the target_detach below
577 doesn't unpush the target. */
579 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
581 parent_inf
= current_inferior ();
582 child_inf
->attach_flag
= parent_inf
->attach_flag
;
583 copy_terminal_info (child_inf
, parent_inf
);
584 child_inf
->gdbarch
= parent_inf
->gdbarch
;
585 copy_inferior_target_desc_info (child_inf
, parent_inf
);
587 parent_pspace
= parent_inf
->pspace
;
589 /* If we're vforking, we want to hold on to the parent until the
590 child exits or execs. At child exec or exit time we can
591 remove the old breakpoints from the parent and detach or
592 resume debugging it. Otherwise, detach the parent now; we'll
593 want to reuse it's program/address spaces, but we can't set
594 them to the child before removing breakpoints from the
595 parent, otherwise, the breakpoints module could decide to
596 remove breakpoints from the wrong process (since they'd be
597 assigned to the same address space). */
601 gdb_assert (child_inf
->vfork_parent
== NULL
);
602 gdb_assert (parent_inf
->vfork_child
== NULL
);
603 child_inf
->vfork_parent
= parent_inf
;
604 child_inf
->pending_detach
= 0;
605 parent_inf
->vfork_child
= child_inf
;
606 parent_inf
->pending_detach
= detach_fork
;
607 parent_inf
->waiting_for_vfork_done
= 0;
609 else if (detach_fork
)
611 if (info_verbose
|| debug_infrun
)
613 /* Ensure that we have a process ptid. */
614 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
616 target_terminal_ours_for_output ();
617 fprintf_filtered (gdb_stdlog
,
618 _("Detaching after fork from "
620 target_pid_to_str (process_ptid
));
623 target_detach (NULL
, 0);
626 /* Note that the detach above makes PARENT_INF dangling. */
628 /* Add the child thread to the appropriate lists, and switch to
629 this new thread, before cloning the program space, and
630 informing the solib layer about this new process. */
632 inferior_ptid
= child_ptid
;
633 add_thread (inferior_ptid
);
635 /* If this is a vfork child, then the address-space is shared
636 with the parent. If we detached from the parent, then we can
637 reuse the parent's program/address spaces. */
638 if (has_vforked
|| detach_fork
)
640 child_inf
->pspace
= parent_pspace
;
641 child_inf
->aspace
= child_inf
->pspace
->aspace
;
645 child_inf
->aspace
= new_address_space ();
646 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
647 child_inf
->removable
= 1;
648 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
649 set_current_program_space (child_inf
->pspace
);
650 clone_program_space (child_inf
->pspace
, parent_pspace
);
652 /* Let the shared library layer (e.g., solib-svr4) learn
653 about this new process, relocate the cloned exec, pull in
654 shared libraries, and install the solib event breakpoint.
655 If a "cloned-VM" event was propagated better throughout
656 the core, this wouldn't be required. */
657 solib_create_inferior_hook (0);
661 return target_follow_fork (follow_child
, detach_fork
);
664 /* Tell the target to follow the fork we're stopped at. Returns true
665 if the inferior should be resumed; false, if the target for some
666 reason decided it's best not to resume. */
671 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
672 int should_resume
= 1;
673 struct thread_info
*tp
;
675 /* Copy user stepping state to the new inferior thread. FIXME: the
676 followed fork child thread should have a copy of most of the
677 parent thread structure's run control related fields, not just these.
678 Initialized to avoid "may be used uninitialized" warnings from gcc. */
679 struct breakpoint
*step_resume_breakpoint
= NULL
;
680 struct breakpoint
*exception_resume_breakpoint
= NULL
;
681 CORE_ADDR step_range_start
= 0;
682 CORE_ADDR step_range_end
= 0;
683 struct frame_id step_frame_id
= { 0 };
684 struct interp
*command_interp
= NULL
;
689 struct target_waitstatus wait_status
;
691 /* Get the last target status returned by target_wait(). */
692 get_last_target_status (&wait_ptid
, &wait_status
);
694 /* If not stopped at a fork event, then there's nothing else to
696 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
697 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
700 /* Check if we switched over from WAIT_PTID, since the event was
702 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
703 && !ptid_equal (inferior_ptid
, wait_ptid
))
705 /* We did. Switch back to WAIT_PTID thread, to tell the
706 target to follow it (in either direction). We'll
707 afterwards refuse to resume, and inform the user what
709 switch_to_thread (wait_ptid
);
714 tp
= inferior_thread ();
716 /* If there were any forks/vforks that were caught and are now to be
717 followed, then do so now. */
718 switch (tp
->pending_follow
.kind
)
720 case TARGET_WAITKIND_FORKED
:
721 case TARGET_WAITKIND_VFORKED
:
723 ptid_t parent
, child
;
725 /* If the user did a next/step, etc, over a fork call,
726 preserve the stepping state in the fork child. */
727 if (follow_child
&& should_resume
)
729 step_resume_breakpoint
= clone_momentary_breakpoint
730 (tp
->control
.step_resume_breakpoint
);
731 step_range_start
= tp
->control
.step_range_start
;
732 step_range_end
= tp
->control
.step_range_end
;
733 step_frame_id
= tp
->control
.step_frame_id
;
734 exception_resume_breakpoint
735 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
736 command_interp
= tp
->control
.command_interp
;
738 /* For now, delete the parent's sr breakpoint, otherwise,
739 parent/child sr breakpoints are considered duplicates,
740 and the child version will not be installed. Remove
741 this when the breakpoints module becomes aware of
742 inferiors and address spaces. */
743 delete_step_resume_breakpoint (tp
);
744 tp
->control
.step_range_start
= 0;
745 tp
->control
.step_range_end
= 0;
746 tp
->control
.step_frame_id
= null_frame_id
;
747 delete_exception_resume_breakpoint (tp
);
748 tp
->control
.command_interp
= NULL
;
751 parent
= inferior_ptid
;
752 child
= tp
->pending_follow
.value
.related_pid
;
754 /* Set up inferior(s) as specified by the caller, and tell the
755 target to do whatever is necessary to follow either parent
757 if (follow_fork_inferior (follow_child
, detach_fork
))
759 /* Target refused to follow, or there's some other reason
760 we shouldn't resume. */
765 /* This pending follow fork event is now handled, one way
766 or another. The previous selected thread may be gone
767 from the lists by now, but if it is still around, need
768 to clear the pending follow request. */
769 tp
= find_thread_ptid (parent
);
771 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
773 /* This makes sure we don't try to apply the "Switched
774 over from WAIT_PID" logic above. */
775 nullify_last_target_wait_ptid ();
777 /* If we followed the child, switch to it... */
780 switch_to_thread (child
);
782 /* ... and preserve the stepping state, in case the
783 user was stepping over the fork call. */
786 tp
= inferior_thread ();
787 tp
->control
.step_resume_breakpoint
788 = step_resume_breakpoint
;
789 tp
->control
.step_range_start
= step_range_start
;
790 tp
->control
.step_range_end
= step_range_end
;
791 tp
->control
.step_frame_id
= step_frame_id
;
792 tp
->control
.exception_resume_breakpoint
793 = exception_resume_breakpoint
;
794 tp
->control
.command_interp
= command_interp
;
798 /* If we get here, it was because we're trying to
799 resume from a fork catchpoint, but, the user
800 has switched threads away from the thread that
801 forked. In that case, the resume command
802 issued is most likely not applicable to the
803 child, so just warn, and refuse to resume. */
804 warning (_("Not resuming: switched threads "
805 "before following fork child."));
808 /* Reset breakpoints in the child as appropriate. */
809 follow_inferior_reset_breakpoints ();
812 switch_to_thread (parent
);
816 case TARGET_WAITKIND_SPURIOUS
:
817 /* Nothing to follow. */
820 internal_error (__FILE__
, __LINE__
,
821 "Unexpected pending_follow.kind %d\n",
822 tp
->pending_follow
.kind
);
826 return should_resume
;
830 follow_inferior_reset_breakpoints (void)
832 struct thread_info
*tp
= inferior_thread ();
834 /* Was there a step_resume breakpoint? (There was if the user
835 did a "next" at the fork() call.) If so, explicitly reset its
836 thread number. Cloned step_resume breakpoints are disabled on
837 creation, so enable it here now that it is associated with the
840 step_resumes are a form of bp that are made to be per-thread.
841 Since we created the step_resume bp when the parent process
842 was being debugged, and now are switching to the child process,
843 from the breakpoint package's viewpoint, that's a switch of
844 "threads". We must update the bp's notion of which thread
845 it is for, or it'll be ignored when it triggers. */
847 if (tp
->control
.step_resume_breakpoint
)
849 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
850 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
853 /* Treat exception_resume breakpoints like step_resume breakpoints. */
854 if (tp
->control
.exception_resume_breakpoint
)
856 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
857 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
860 /* Reinsert all breakpoints in the child. The user may have set
861 breakpoints after catching the fork, in which case those
862 were never set in the child, but only in the parent. This makes
863 sure the inserted breakpoints match the breakpoint list. */
865 breakpoint_re_set ();
866 insert_breakpoints ();
869 /* The child has exited or execed: resume threads of the parent the
870 user wanted to be executing. */
873 proceed_after_vfork_done (struct thread_info
*thread
,
876 int pid
= * (int *) arg
;
878 if (ptid_get_pid (thread
->ptid
) == pid
879 && is_running (thread
->ptid
)
880 && !is_executing (thread
->ptid
)
881 && !thread
->stop_requested
882 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
885 fprintf_unfiltered (gdb_stdlog
,
886 "infrun: resuming vfork parent thread %s\n",
887 target_pid_to_str (thread
->ptid
));
889 switch_to_thread (thread
->ptid
);
890 clear_proceed_status (0);
891 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
897 /* Called whenever we notice an exec or exit event, to handle
898 detaching or resuming a vfork parent. */
901 handle_vfork_child_exec_or_exit (int exec
)
903 struct inferior
*inf
= current_inferior ();
905 if (inf
->vfork_parent
)
907 int resume_parent
= -1;
909 /* This exec or exit marks the end of the shared memory region
910 between the parent and the child. If the user wanted to
911 detach from the parent, now is the time. */
913 if (inf
->vfork_parent
->pending_detach
)
915 struct thread_info
*tp
;
916 struct cleanup
*old_chain
;
917 struct program_space
*pspace
;
918 struct address_space
*aspace
;
920 /* follow-fork child, detach-on-fork on. */
922 inf
->vfork_parent
->pending_detach
= 0;
926 /* If we're handling a child exit, then inferior_ptid
927 points at the inferior's pid, not to a thread. */
928 old_chain
= save_inferior_ptid ();
929 save_current_program_space ();
930 save_current_inferior ();
933 old_chain
= save_current_space_and_thread ();
935 /* We're letting loose of the parent. */
936 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
937 switch_to_thread (tp
->ptid
);
939 /* We're about to detach from the parent, which implicitly
940 removes breakpoints from its address space. There's a
941 catch here: we want to reuse the spaces for the child,
942 but, parent/child are still sharing the pspace at this
943 point, although the exec in reality makes the kernel give
944 the child a fresh set of new pages. The problem here is
945 that the breakpoints module being unaware of this, would
946 likely chose the child process to write to the parent
947 address space. Swapping the child temporarily away from
948 the spaces has the desired effect. Yes, this is "sort
951 pspace
= inf
->pspace
;
952 aspace
= inf
->aspace
;
956 if (debug_infrun
|| info_verbose
)
958 target_terminal_ours_for_output ();
962 fprintf_filtered (gdb_stdlog
,
963 _("Detaching vfork parent process "
964 "%d after child exec.\n"),
965 inf
->vfork_parent
->pid
);
969 fprintf_filtered (gdb_stdlog
,
970 _("Detaching vfork parent process "
971 "%d after child exit.\n"),
972 inf
->vfork_parent
->pid
);
976 target_detach (NULL
, 0);
979 inf
->pspace
= pspace
;
980 inf
->aspace
= aspace
;
982 do_cleanups (old_chain
);
986 /* We're staying attached to the parent, so, really give the
987 child a new address space. */
988 inf
->pspace
= add_program_space (maybe_new_address_space ());
989 inf
->aspace
= inf
->pspace
->aspace
;
991 set_current_program_space (inf
->pspace
);
993 resume_parent
= inf
->vfork_parent
->pid
;
995 /* Break the bonds. */
996 inf
->vfork_parent
->vfork_child
= NULL
;
1000 struct cleanup
*old_chain
;
1001 struct program_space
*pspace
;
1003 /* If this is a vfork child exiting, then the pspace and
1004 aspaces were shared with the parent. Since we're
1005 reporting the process exit, we'll be mourning all that is
1006 found in the address space, and switching to null_ptid,
1007 preparing to start a new inferior. But, since we don't
1008 want to clobber the parent's address/program spaces, we
1009 go ahead and create a new one for this exiting
1012 /* Switch to null_ptid, so that clone_program_space doesn't want
1013 to read the selected frame of a dead process. */
1014 old_chain
= save_inferior_ptid ();
1015 inferior_ptid
= null_ptid
;
1017 /* This inferior is dead, so avoid giving the breakpoints
1018 module the option to write through to it (cloning a
1019 program space resets breakpoints). */
1022 pspace
= add_program_space (maybe_new_address_space ());
1023 set_current_program_space (pspace
);
1025 inf
->symfile_flags
= SYMFILE_NO_READ
;
1026 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1027 inf
->pspace
= pspace
;
1028 inf
->aspace
= pspace
->aspace
;
1030 /* Put back inferior_ptid. We'll continue mourning this
1032 do_cleanups (old_chain
);
1034 resume_parent
= inf
->vfork_parent
->pid
;
1035 /* Break the bonds. */
1036 inf
->vfork_parent
->vfork_child
= NULL
;
1039 inf
->vfork_parent
= NULL
;
1041 gdb_assert (current_program_space
== inf
->pspace
);
1043 if (non_stop
&& resume_parent
!= -1)
1045 /* If the user wanted the parent to be running, let it go
1047 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1050 fprintf_unfiltered (gdb_stdlog
,
1051 "infrun: resuming vfork parent process %d\n",
1054 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1056 do_cleanups (old_chain
);
1061 /* Enum strings for "set|show follow-exec-mode". */
1063 static const char follow_exec_mode_new
[] = "new";
1064 static const char follow_exec_mode_same
[] = "same";
1065 static const char *const follow_exec_mode_names
[] =
1067 follow_exec_mode_new
,
1068 follow_exec_mode_same
,
1072 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1074 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1075 struct cmd_list_element
*c
, const char *value
)
1077 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1080 /* EXECD_PATHNAME is assumed to be non-NULL. */
1083 follow_exec (ptid_t ptid
, char *execd_pathname
)
1085 struct thread_info
*th
, *tmp
;
1086 struct inferior
*inf
= current_inferior ();
1087 int pid
= ptid_get_pid (ptid
);
1088 ptid_t process_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 process_ptid
= pid_to_ptid (pid
);
1156 printf_unfiltered (_("%s is executing new program: %s\n"),
1157 target_pid_to_str (process_ptid
),
1160 /* We've followed the inferior through an exec. Therefore, the
1161 inferior has essentially been killed & reborn. */
1163 gdb_flush (gdb_stdout
);
1165 breakpoint_init_inferior (inf_execd
);
1167 if (*gdb_sysroot
!= '\0')
1169 char *name
= exec_file_find (execd_pathname
, NULL
);
1171 execd_pathname
= (char *) alloca (strlen (name
) + 1);
1172 strcpy (execd_pathname
, name
);
1176 /* Reset the shared library package. This ensures that we get a
1177 shlib event when the child reaches "_start", at which point the
1178 dld will have had a chance to initialize the child. */
1179 /* Also, loading a symbol file below may trigger symbol lookups, and
1180 we don't want those to be satisfied by the libraries of the
1181 previous incarnation of this process. */
1182 no_shared_libraries (NULL
, 0);
1184 if (follow_exec_mode_string
== follow_exec_mode_new
)
1186 /* The user wants to keep the old inferior and program spaces
1187 around. Create a new fresh one, and switch to it. */
1189 /* Do exit processing for the original inferior before adding
1190 the new inferior so we don't have two active inferiors with
1191 the same ptid, which can confuse find_inferior_ptid. */
1192 exit_inferior_num_silent (current_inferior ()->num
);
1194 inf
= add_inferior_with_spaces ();
1196 target_follow_exec (inf
, execd_pathname
);
1198 set_current_inferior (inf
);
1199 set_current_program_space (inf
->pspace
);
1204 /* The old description may no longer be fit for the new image.
1205 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1206 old description; we'll read a new one below. No need to do
1207 this on "follow-exec-mode new", as the old inferior stays
1208 around (its description is later cleared/refetched on
1210 target_clear_description ();
1213 gdb_assert (current_program_space
== inf
->pspace
);
1215 /* That a.out is now the one to use. */
1216 exec_file_attach (execd_pathname
, 0);
1218 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1219 (Position Independent Executable) main symbol file will get applied by
1220 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1221 the breakpoints with the zero displacement. */
1223 symbol_file_add (execd_pathname
,
1225 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
1228 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
1229 set_initial_language ();
1231 /* If the target can specify a description, read it. Must do this
1232 after flipping to the new executable (because the target supplied
1233 description must be compatible with the executable's
1234 architecture, and the old executable may e.g., be 32-bit, while
1235 the new one 64-bit), and before anything involving memory or
1237 target_find_description ();
1239 solib_create_inferior_hook (0);
1241 jit_inferior_created_hook ();
1243 breakpoint_re_set ();
1245 /* Reinsert all breakpoints. (Those which were symbolic have
1246 been reset to the proper address in the new a.out, thanks
1247 to symbol_file_command...). */
1248 insert_breakpoints ();
1250 /* The next resume of this inferior should bring it to the shlib
1251 startup breakpoints. (If the user had also set bp's on
1252 "main" from the old (parent) process, then they'll auto-
1253 matically get reset there in the new process.). */
1256 /* The queue of threads that need to do a step-over operation to get
1257 past e.g., a breakpoint. What technique is used to step over the
1258 breakpoint/watchpoint does not matter -- all threads end up in the
1259 same queue, to maintain rough temporal order of execution, in order
1260 to avoid starvation, otherwise, we could e.g., find ourselves
1261 constantly stepping the same couple threads past their breakpoints
1262 over and over, if the single-step finish fast enough. */
1263 struct thread_info
*step_over_queue_head
;
1265 /* Bit flags indicating what the thread needs to step over. */
1267 enum step_over_what_flag
1269 /* Step over a breakpoint. */
1270 STEP_OVER_BREAKPOINT
= 1,
1272 /* Step past a non-continuable watchpoint, in order to let the
1273 instruction execute so we can evaluate the watchpoint
1275 STEP_OVER_WATCHPOINT
= 2
1277 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1279 /* Info about an instruction that is being stepped over. */
1281 struct step_over_info
1283 /* If we're stepping past a breakpoint, this is the address space
1284 and address of the instruction the breakpoint is set at. We'll
1285 skip inserting all breakpoints here. Valid iff ASPACE is
1287 struct address_space
*aspace
;
1290 /* The instruction being stepped over triggers a nonsteppable
1291 watchpoint. If true, we'll skip inserting watchpoints. */
1292 int nonsteppable_watchpoint_p
;
1294 /* The thread's global number. */
1298 /* The step-over info of the location that is being stepped over.
1300 Note that with async/breakpoint always-inserted mode, a user might
1301 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1302 being stepped over. As setting a new breakpoint inserts all
1303 breakpoints, we need to make sure the breakpoint being stepped over
1304 isn't inserted then. We do that by only clearing the step-over
1305 info when the step-over is actually finished (or aborted).
1307 Presently GDB can only step over one breakpoint at any given time.
1308 Given threads that can't run code in the same address space as the
1309 breakpoint's can't really miss the breakpoint, GDB could be taught
1310 to step-over at most one breakpoint per address space (so this info
1311 could move to the address space object if/when GDB is extended).
1312 The set of breakpoints being stepped over will normally be much
1313 smaller than the set of all breakpoints, so a flag in the
1314 breakpoint location structure would be wasteful. A separate list
1315 also saves complexity and run-time, as otherwise we'd have to go
1316 through all breakpoint locations clearing their flag whenever we
1317 start a new sequence. Similar considerations weigh against storing
1318 this info in the thread object. Plus, not all step overs actually
1319 have breakpoint locations -- e.g., stepping past a single-step
1320 breakpoint, or stepping to complete a non-continuable
1322 static struct step_over_info step_over_info
;
1324 /* Record the address of the breakpoint/instruction we're currently
1328 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1329 int nonsteppable_watchpoint_p
,
1332 step_over_info
.aspace
= aspace
;
1333 step_over_info
.address
= address
;
1334 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1335 step_over_info
.thread
= thread
;
1338 /* Called when we're not longer stepping over a breakpoint / an
1339 instruction, so all breakpoints are free to be (re)inserted. */
1342 clear_step_over_info (void)
1345 fprintf_unfiltered (gdb_stdlog
,
1346 "infrun: clear_step_over_info\n");
1347 step_over_info
.aspace
= NULL
;
1348 step_over_info
.address
= 0;
1349 step_over_info
.nonsteppable_watchpoint_p
= 0;
1350 step_over_info
.thread
= -1;
1356 stepping_past_instruction_at (struct address_space
*aspace
,
1359 return (step_over_info
.aspace
!= NULL
1360 && breakpoint_address_match (aspace
, address
,
1361 step_over_info
.aspace
,
1362 step_over_info
.address
));
1368 thread_is_stepping_over_breakpoint (int thread
)
1370 return (step_over_info
.thread
!= -1
1371 && thread
== step_over_info
.thread
);
1377 stepping_past_nonsteppable_watchpoint (void)
1379 return step_over_info
.nonsteppable_watchpoint_p
;
1382 /* Returns true if step-over info is valid. */
1385 step_over_info_valid_p (void)
1387 return (step_over_info
.aspace
!= NULL
1388 || stepping_past_nonsteppable_watchpoint ());
1392 /* Displaced stepping. */
1394 /* In non-stop debugging mode, we must take special care to manage
1395 breakpoints properly; in particular, the traditional strategy for
1396 stepping a thread past a breakpoint it has hit is unsuitable.
1397 'Displaced stepping' is a tactic for stepping one thread past a
1398 breakpoint it has hit while ensuring that other threads running
1399 concurrently will hit the breakpoint as they should.
1401 The traditional way to step a thread T off a breakpoint in a
1402 multi-threaded program in all-stop mode is as follows:
1404 a0) Initially, all threads are stopped, and breakpoints are not
1406 a1) We single-step T, leaving breakpoints uninserted.
1407 a2) We insert breakpoints, and resume all threads.
1409 In non-stop debugging, however, this strategy is unsuitable: we
1410 don't want to have to stop all threads in the system in order to
1411 continue or step T past a breakpoint. Instead, we use displaced
1414 n0) Initially, T is stopped, other threads are running, and
1415 breakpoints are inserted.
1416 n1) We copy the instruction "under" the breakpoint to a separate
1417 location, outside the main code stream, making any adjustments
1418 to the instruction, register, and memory state as directed by
1420 n2) We single-step T over the instruction at its new location.
1421 n3) We adjust the resulting register and memory state as directed
1422 by T's architecture. This includes resetting T's PC to point
1423 back into the main instruction stream.
1426 This approach depends on the following gdbarch methods:
1428 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1429 indicate where to copy the instruction, and how much space must
1430 be reserved there. We use these in step n1.
1432 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1433 address, and makes any necessary adjustments to the instruction,
1434 register contents, and memory. We use this in step n1.
1436 - gdbarch_displaced_step_fixup adjusts registers and memory after
1437 we have successfuly single-stepped the instruction, to yield the
1438 same effect the instruction would have had if we had executed it
1439 at its original address. We use this in step n3.
1441 - gdbarch_displaced_step_free_closure provides cleanup.
1443 The gdbarch_displaced_step_copy_insn and
1444 gdbarch_displaced_step_fixup functions must be written so that
1445 copying an instruction with gdbarch_displaced_step_copy_insn,
1446 single-stepping across the copied instruction, and then applying
1447 gdbarch_displaced_insn_fixup should have the same effects on the
1448 thread's memory and registers as stepping the instruction in place
1449 would have. Exactly which responsibilities fall to the copy and
1450 which fall to the fixup is up to the author of those functions.
1452 See the comments in gdbarch.sh for details.
1454 Note that displaced stepping and software single-step cannot
1455 currently be used in combination, although with some care I think
1456 they could be made to. Software single-step works by placing
1457 breakpoints on all possible subsequent instructions; if the
1458 displaced instruction is a PC-relative jump, those breakpoints
1459 could fall in very strange places --- on pages that aren't
1460 executable, or at addresses that are not proper instruction
1461 boundaries. (We do generally let other threads run while we wait
1462 to hit the software single-step breakpoint, and they might
1463 encounter such a corrupted instruction.) One way to work around
1464 this would be to have gdbarch_displaced_step_copy_insn fully
1465 simulate the effect of PC-relative instructions (and return NULL)
1466 on architectures that use software single-stepping.
1468 In non-stop mode, we can have independent and simultaneous step
1469 requests, so more than one thread may need to simultaneously step
1470 over a breakpoint. The current implementation assumes there is
1471 only one scratch space per process. In this case, we have to
1472 serialize access to the scratch space. If thread A wants to step
1473 over a breakpoint, but we are currently waiting for some other
1474 thread to complete a displaced step, we leave thread A stopped and
1475 place it in the displaced_step_request_queue. Whenever a displaced
1476 step finishes, we pick the next thread in the queue and start a new
1477 displaced step operation on it. See displaced_step_prepare and
1478 displaced_step_fixup for details. */
1480 /* Per-inferior displaced stepping state. */
1481 struct displaced_step_inferior_state
1483 /* Pointer to next in linked list. */
1484 struct displaced_step_inferior_state
*next
;
1486 /* The process this displaced step state refers to. */
1489 /* True if preparing a displaced step ever failed. If so, we won't
1490 try displaced stepping for this inferior again. */
1493 /* If this is not null_ptid, this is the thread carrying out a
1494 displaced single-step in process PID. This thread's state will
1495 require fixing up once it has completed its step. */
1498 /* The architecture the thread had when we stepped it. */
1499 struct gdbarch
*step_gdbarch
;
1501 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1502 for post-step cleanup. */
1503 struct displaced_step_closure
*step_closure
;
1505 /* The address of the original instruction, and the copy we
1507 CORE_ADDR step_original
, step_copy
;
1509 /* Saved contents of copy area. */
1510 gdb_byte
*step_saved_copy
;
1513 /* The list of states of processes involved in displaced stepping
1515 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1517 /* Get the displaced stepping state of process PID. */
1519 static struct displaced_step_inferior_state
*
1520 get_displaced_stepping_state (int pid
)
1522 struct displaced_step_inferior_state
*state
;
1524 for (state
= displaced_step_inferior_states
;
1526 state
= state
->next
)
1527 if (state
->pid
== pid
)
1533 /* Returns true if any inferior has a thread doing a displaced
1537 displaced_step_in_progress_any_inferior (void)
1539 struct displaced_step_inferior_state
*state
;
1541 for (state
= displaced_step_inferior_states
;
1543 state
= state
->next
)
1544 if (!ptid_equal (state
->step_ptid
, null_ptid
))
1550 /* Return true if thread represented by PTID is doing a displaced
1554 displaced_step_in_progress_thread (ptid_t ptid
)
1556 struct displaced_step_inferior_state
*displaced
;
1558 gdb_assert (!ptid_equal (ptid
, null_ptid
));
1560 displaced
= get_displaced_stepping_state (ptid_get_pid (ptid
));
1562 return (displaced
!= NULL
&& ptid_equal (displaced
->step_ptid
, ptid
));
1565 /* Return true if process PID has a thread doing a displaced step. */
1568 displaced_step_in_progress (int pid
)
1570 struct displaced_step_inferior_state
*displaced
;
1572 displaced
= get_displaced_stepping_state (pid
);
1573 if (displaced
!= NULL
&& !ptid_equal (displaced
->step_ptid
, null_ptid
))
1579 /* Add a new displaced stepping state for process PID to the displaced
1580 stepping state list, or return a pointer to an already existing
1581 entry, if it already exists. Never returns NULL. */
1583 static struct displaced_step_inferior_state
*
1584 add_displaced_stepping_state (int pid
)
1586 struct displaced_step_inferior_state
*state
;
1588 for (state
= displaced_step_inferior_states
;
1590 state
= state
->next
)
1591 if (state
->pid
== pid
)
1594 state
= XCNEW (struct displaced_step_inferior_state
);
1596 state
->next
= displaced_step_inferior_states
;
1597 displaced_step_inferior_states
= state
;
1602 /* If inferior is in displaced stepping, and ADDR equals to starting address
1603 of copy area, return corresponding displaced_step_closure. Otherwise,
1606 struct displaced_step_closure
*
1607 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1609 struct displaced_step_inferior_state
*displaced
1610 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1612 /* If checking the mode of displaced instruction in copy area. */
1613 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1614 && (displaced
->step_copy
== addr
))
1615 return displaced
->step_closure
;
1620 /* Remove the displaced stepping state of process PID. */
1623 remove_displaced_stepping_state (int pid
)
1625 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1627 gdb_assert (pid
!= 0);
1629 it
= displaced_step_inferior_states
;
1630 prev_next_p
= &displaced_step_inferior_states
;
1635 *prev_next_p
= it
->next
;
1640 prev_next_p
= &it
->next
;
1646 infrun_inferior_exit (struct inferior
*inf
)
1648 remove_displaced_stepping_state (inf
->pid
);
1651 /* If ON, and the architecture supports it, GDB will use displaced
1652 stepping to step over breakpoints. If OFF, or if the architecture
1653 doesn't support it, GDB will instead use the traditional
1654 hold-and-step approach. If AUTO (which is the default), GDB will
1655 decide which technique to use to step over breakpoints depending on
1656 which of all-stop or non-stop mode is active --- displaced stepping
1657 in non-stop mode; hold-and-step in all-stop mode. */
1659 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1662 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1663 struct cmd_list_element
*c
,
1666 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1667 fprintf_filtered (file
,
1668 _("Debugger's willingness to use displaced stepping "
1669 "to step over breakpoints is %s (currently %s).\n"),
1670 value
, target_is_non_stop_p () ? "on" : "off");
1672 fprintf_filtered (file
,
1673 _("Debugger's willingness to use displaced stepping "
1674 "to step over breakpoints is %s.\n"), value
);
1677 /* Return non-zero if displaced stepping can/should be used to step
1678 over breakpoints of thread TP. */
1681 use_displaced_stepping (struct thread_info
*tp
)
1683 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
1684 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1685 struct displaced_step_inferior_state
*displaced_state
;
1687 displaced_state
= get_displaced_stepping_state (ptid_get_pid (tp
->ptid
));
1689 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1690 && target_is_non_stop_p ())
1691 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1692 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1693 && find_record_target () == NULL
1694 && (displaced_state
== NULL
1695 || !displaced_state
->failed_before
));
1698 /* Clean out any stray displaced stepping state. */
1700 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1702 /* Indicate that there is no cleanup pending. */
1703 displaced
->step_ptid
= null_ptid
;
1705 if (displaced
->step_closure
)
1707 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1708 displaced
->step_closure
);
1709 displaced
->step_closure
= NULL
;
1714 displaced_step_clear_cleanup (void *arg
)
1716 struct displaced_step_inferior_state
*state
1717 = (struct displaced_step_inferior_state
*) arg
;
1719 displaced_step_clear (state
);
1722 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1724 displaced_step_dump_bytes (struct ui_file
*file
,
1725 const gdb_byte
*buf
,
1730 for (i
= 0; i
< len
; i
++)
1731 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1732 fputs_unfiltered ("\n", file
);
1735 /* Prepare to single-step, using displaced stepping.
1737 Note that we cannot use displaced stepping when we have a signal to
1738 deliver. If we have a signal to deliver and an instruction to step
1739 over, then after the step, there will be no indication from the
1740 target whether the thread entered a signal handler or ignored the
1741 signal and stepped over the instruction successfully --- both cases
1742 result in a simple SIGTRAP. In the first case we mustn't do a
1743 fixup, and in the second case we must --- but we can't tell which.
1744 Comments in the code for 'random signals' in handle_inferior_event
1745 explain how we handle this case instead.
1747 Returns 1 if preparing was successful -- this thread is going to be
1748 stepped now; 0 if displaced stepping this thread got queued; or -1
1749 if this instruction can't be displaced stepped. */
1752 displaced_step_prepare_throw (ptid_t ptid
)
1754 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1755 struct thread_info
*tp
= find_thread_ptid (ptid
);
1756 struct regcache
*regcache
= get_thread_regcache (ptid
);
1757 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1758 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1759 CORE_ADDR original
, copy
;
1761 struct displaced_step_closure
*closure
;
1762 struct displaced_step_inferior_state
*displaced
;
1765 /* We should never reach this function if the architecture does not
1766 support displaced stepping. */
1767 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1769 /* Nor if the thread isn't meant to step over a breakpoint. */
1770 gdb_assert (tp
->control
.trap_expected
);
1772 /* Disable range stepping while executing in the scratch pad. We
1773 want a single-step even if executing the displaced instruction in
1774 the scratch buffer lands within the stepping range (e.g., a
1776 tp
->control
.may_range_step
= 0;
1778 /* We have to displaced step one thread at a time, as we only have
1779 access to a single scratch space per inferior. */
1781 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1783 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1785 /* Already waiting for a displaced step to finish. Defer this
1786 request and place in queue. */
1788 if (debug_displaced
)
1789 fprintf_unfiltered (gdb_stdlog
,
1790 "displaced: deferring step of %s\n",
1791 target_pid_to_str (ptid
));
1793 thread_step_over_chain_enqueue (tp
);
1798 if (debug_displaced
)
1799 fprintf_unfiltered (gdb_stdlog
,
1800 "displaced: stepping %s now\n",
1801 target_pid_to_str (ptid
));
1804 displaced_step_clear (displaced
);
1806 old_cleanups
= save_inferior_ptid ();
1807 inferior_ptid
= ptid
;
1809 original
= regcache_read_pc (regcache
);
1811 copy
= gdbarch_displaced_step_location (gdbarch
);
1812 len
= gdbarch_max_insn_length (gdbarch
);
1814 if (breakpoint_in_range_p (aspace
, copy
, len
))
1816 /* There's a breakpoint set in the scratch pad location range
1817 (which is usually around the entry point). We'd either
1818 install it before resuming, which would overwrite/corrupt the
1819 scratch pad, or if it was already inserted, this displaced
1820 step would overwrite it. The latter is OK in the sense that
1821 we already assume that no thread is going to execute the code
1822 in the scratch pad range (after initial startup) anyway, but
1823 the former is unacceptable. Simply punt and fallback to
1824 stepping over this breakpoint in-line. */
1825 if (debug_displaced
)
1827 fprintf_unfiltered (gdb_stdlog
,
1828 "displaced: breakpoint set in scratch pad. "
1829 "Stepping over breakpoint in-line instead.\n");
1832 do_cleanups (old_cleanups
);
1836 /* Save the original contents of the copy area. */
1837 displaced
->step_saved_copy
= (gdb_byte
*) xmalloc (len
);
1838 ignore_cleanups
= make_cleanup (free_current_contents
,
1839 &displaced
->step_saved_copy
);
1840 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1842 throw_error (MEMORY_ERROR
,
1843 _("Error accessing memory address %s (%s) for "
1844 "displaced-stepping scratch space."),
1845 paddress (gdbarch
, copy
), safe_strerror (status
));
1846 if (debug_displaced
)
1848 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1849 paddress (gdbarch
, copy
));
1850 displaced_step_dump_bytes (gdb_stdlog
,
1851 displaced
->step_saved_copy
,
1855 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1856 original
, copy
, regcache
);
1857 if (closure
== NULL
)
1859 /* The architecture doesn't know how or want to displaced step
1860 this instruction or instruction sequence. Fallback to
1861 stepping over the breakpoint in-line. */
1862 do_cleanups (old_cleanups
);
1866 /* Save the information we need to fix things up if the step
1868 displaced
->step_ptid
= ptid
;
1869 displaced
->step_gdbarch
= gdbarch
;
1870 displaced
->step_closure
= closure
;
1871 displaced
->step_original
= original
;
1872 displaced
->step_copy
= copy
;
1874 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1876 /* Resume execution at the copy. */
1877 regcache_write_pc (regcache
, copy
);
1879 discard_cleanups (ignore_cleanups
);
1881 do_cleanups (old_cleanups
);
1883 if (debug_displaced
)
1884 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1885 paddress (gdbarch
, copy
));
1890 /* Wrapper for displaced_step_prepare_throw that disabled further
1891 attempts at displaced stepping if we get a memory error. */
1894 displaced_step_prepare (ptid_t ptid
)
1900 prepared
= displaced_step_prepare_throw (ptid
);
1902 CATCH (ex
, RETURN_MASK_ERROR
)
1904 struct displaced_step_inferior_state
*displaced_state
;
1906 if (ex
.error
!= MEMORY_ERROR
1907 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1908 throw_exception (ex
);
1912 fprintf_unfiltered (gdb_stdlog
,
1913 "infrun: disabling displaced stepping: %s\n",
1917 /* Be verbose if "set displaced-stepping" is "on", silent if
1919 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1921 warning (_("disabling displaced stepping: %s"),
1925 /* Disable further displaced stepping attempts. */
1927 = get_displaced_stepping_state (ptid_get_pid (ptid
));
1928 displaced_state
->failed_before
= 1;
1936 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1937 const gdb_byte
*myaddr
, int len
)
1939 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1941 inferior_ptid
= ptid
;
1942 write_memory (memaddr
, myaddr
, len
);
1943 do_cleanups (ptid_cleanup
);
1946 /* Restore the contents of the copy area for thread PTID. */
1949 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1952 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1954 write_memory_ptid (ptid
, displaced
->step_copy
,
1955 displaced
->step_saved_copy
, len
);
1956 if (debug_displaced
)
1957 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1958 target_pid_to_str (ptid
),
1959 paddress (displaced
->step_gdbarch
,
1960 displaced
->step_copy
));
1963 /* If we displaced stepped an instruction successfully, adjust
1964 registers and memory to yield the same effect the instruction would
1965 have had if we had executed it at its original address, and return
1966 1. If the instruction didn't complete, relocate the PC and return
1967 -1. If the thread wasn't displaced stepping, return 0. */
1970 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1972 struct cleanup
*old_cleanups
;
1973 struct displaced_step_inferior_state
*displaced
1974 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1977 /* Was any thread of this process doing a displaced step? */
1978 if (displaced
== NULL
)
1981 /* Was this event for the pid we displaced? */
1982 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1983 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1986 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1988 displaced_step_restore (displaced
, displaced
->step_ptid
);
1990 /* Fixup may need to read memory/registers. Switch to the thread
1991 that we're fixing up. Also, target_stopped_by_watchpoint checks
1992 the current thread. */
1993 switch_to_thread (event_ptid
);
1995 /* Did the instruction complete successfully? */
1996 if (signal
== GDB_SIGNAL_TRAP
1997 && !(target_stopped_by_watchpoint ()
1998 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
1999 || target_have_steppable_watchpoint
)))
2001 /* Fix up the resulting state. */
2002 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
2003 displaced
->step_closure
,
2004 displaced
->step_original
,
2005 displaced
->step_copy
,
2006 get_thread_regcache (displaced
->step_ptid
));
2011 /* Since the instruction didn't complete, all we can do is
2013 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
2014 CORE_ADDR pc
= regcache_read_pc (regcache
);
2016 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
2017 regcache_write_pc (regcache
, pc
);
2021 do_cleanups (old_cleanups
);
2023 displaced
->step_ptid
= null_ptid
;
2028 /* Data to be passed around while handling an event. This data is
2029 discarded between events. */
2030 struct execution_control_state
2033 /* The thread that got the event, if this was a thread event; NULL
2035 struct thread_info
*event_thread
;
2037 struct target_waitstatus ws
;
2038 int stop_func_filled_in
;
2039 CORE_ADDR stop_func_start
;
2040 CORE_ADDR stop_func_end
;
2041 const char *stop_func_name
;
2044 /* True if the event thread hit the single-step breakpoint of
2045 another thread. Thus the event doesn't cause a stop, the thread
2046 needs to be single-stepped past the single-step breakpoint before
2047 we can switch back to the original stepping thread. */
2048 int hit_singlestep_breakpoint
;
2051 /* Clear ECS and set it to point at TP. */
2054 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
2056 memset (ecs
, 0, sizeof (*ecs
));
2057 ecs
->event_thread
= tp
;
2058 ecs
->ptid
= tp
->ptid
;
2061 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
2062 static void prepare_to_wait (struct execution_control_state
*ecs
);
2063 static int keep_going_stepped_thread (struct thread_info
*tp
);
2064 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
2066 /* Are there any pending step-over requests? If so, run all we can
2067 now and return true. Otherwise, return false. */
2070 start_step_over (void)
2072 struct thread_info
*tp
, *next
;
2074 /* Don't start a new step-over if we already have an in-line
2075 step-over operation ongoing. */
2076 if (step_over_info_valid_p ())
2079 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
2081 struct execution_control_state ecss
;
2082 struct execution_control_state
*ecs
= &ecss
;
2083 step_over_what step_what
;
2084 int must_be_in_line
;
2086 next
= thread_step_over_chain_next (tp
);
2088 /* If this inferior already has a displaced step in process,
2089 don't start a new one. */
2090 if (displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2093 step_what
= thread_still_needs_step_over (tp
);
2094 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
2095 || ((step_what
& STEP_OVER_BREAKPOINT
)
2096 && !use_displaced_stepping (tp
)));
2098 /* We currently stop all threads of all processes to step-over
2099 in-line. If we need to start a new in-line step-over, let
2100 any pending displaced steps finish first. */
2101 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
2104 thread_step_over_chain_remove (tp
);
2106 if (step_over_queue_head
== NULL
)
2109 fprintf_unfiltered (gdb_stdlog
,
2110 "infrun: step-over queue now empty\n");
2113 if (tp
->control
.trap_expected
2117 internal_error (__FILE__
, __LINE__
,
2118 "[%s] has inconsistent state: "
2119 "trap_expected=%d, resumed=%d, executing=%d\n",
2120 target_pid_to_str (tp
->ptid
),
2121 tp
->control
.trap_expected
,
2127 fprintf_unfiltered (gdb_stdlog
,
2128 "infrun: resuming [%s] for step-over\n",
2129 target_pid_to_str (tp
->ptid
));
2131 /* keep_going_pass_signal skips the step-over if the breakpoint
2132 is no longer inserted. In all-stop, we want to keep looking
2133 for a thread that needs a step-over instead of resuming TP,
2134 because we wouldn't be able to resume anything else until the
2135 target stops again. In non-stop, the resume always resumes
2136 only TP, so it's OK to let the thread resume freely. */
2137 if (!target_is_non_stop_p () && !step_what
)
2140 switch_to_thread (tp
->ptid
);
2141 reset_ecs (ecs
, tp
);
2142 keep_going_pass_signal (ecs
);
2144 if (!ecs
->wait_some_more
)
2145 error (_("Command aborted."));
2147 gdb_assert (tp
->resumed
);
2149 /* If we started a new in-line step-over, we're done. */
2150 if (step_over_info_valid_p ())
2152 gdb_assert (tp
->control
.trap_expected
);
2156 if (!target_is_non_stop_p ())
2158 /* On all-stop, shouldn't have resumed unless we needed a
2160 gdb_assert (tp
->control
.trap_expected
2161 || tp
->step_after_step_resume_breakpoint
);
2163 /* With remote targets (at least), in all-stop, we can't
2164 issue any further remote commands until the program stops
2169 /* Either the thread no longer needed a step-over, or a new
2170 displaced stepping sequence started. Even in the latter
2171 case, continue looking. Maybe we can also start another
2172 displaced step on a thread of other process. */
2178 /* Update global variables holding ptids to hold NEW_PTID if they were
2179 holding OLD_PTID. */
2181 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2183 struct displaced_step_inferior_state
*displaced
;
2185 if (ptid_equal (inferior_ptid
, old_ptid
))
2186 inferior_ptid
= new_ptid
;
2188 for (displaced
= displaced_step_inferior_states
;
2190 displaced
= displaced
->next
)
2192 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
2193 displaced
->step_ptid
= new_ptid
;
2200 /* Things to clean up if we QUIT out of resume (). */
2202 resume_cleanups (void *ignore
)
2204 if (!ptid_equal (inferior_ptid
, null_ptid
))
2205 delete_single_step_breakpoints (inferior_thread ());
2210 static const char schedlock_off
[] = "off";
2211 static const char schedlock_on
[] = "on";
2212 static const char schedlock_step
[] = "step";
2213 static const char schedlock_replay
[] = "replay";
2214 static const char *const scheduler_enums
[] = {
2221 static const char *scheduler_mode
= schedlock_replay
;
2223 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2224 struct cmd_list_element
*c
, const char *value
)
2226 fprintf_filtered (file
,
2227 _("Mode for locking scheduler "
2228 "during execution is \"%s\".\n"),
2233 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
2235 if (!target_can_lock_scheduler
)
2237 scheduler_mode
= schedlock_off
;
2238 error (_("Target '%s' cannot support this command."), target_shortname
);
2242 /* True if execution commands resume all threads of all processes by
2243 default; otherwise, resume only threads of the current inferior
2245 int sched_multi
= 0;
2247 /* Try to setup for software single stepping over the specified location.
2248 Return 1 if target_resume() should use hardware single step.
2250 GDBARCH the current gdbarch.
2251 PC the location to step over. */
2254 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2258 if (execution_direction
== EXEC_FORWARD
2259 && gdbarch_software_single_step_p (gdbarch
)
2260 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
2270 user_visible_resume_ptid (int step
)
2276 /* With non-stop mode on, threads are always handled
2278 resume_ptid
= inferior_ptid
;
2280 else if ((scheduler_mode
== schedlock_on
)
2281 || (scheduler_mode
== schedlock_step
&& step
))
2283 /* User-settable 'scheduler' mode requires solo thread
2285 resume_ptid
= inferior_ptid
;
2287 else if ((scheduler_mode
== schedlock_replay
)
2288 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2290 /* User-settable 'scheduler' mode requires solo thread resume in replay
2292 resume_ptid
= inferior_ptid
;
2294 else if (!sched_multi
&& target_supports_multi_process ())
2296 /* Resume all threads of the current process (and none of other
2298 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2302 /* Resume all threads of all processes. */
2303 resume_ptid
= RESUME_ALL
;
2309 /* Return a ptid representing the set of threads that we will resume,
2310 in the perspective of the target, assuming run control handling
2311 does not require leaving some threads stopped (e.g., stepping past
2312 breakpoint). USER_STEP indicates whether we're about to start the
2313 target for a stepping command. */
2316 internal_resume_ptid (int user_step
)
2318 /* In non-stop, we always control threads individually. Note that
2319 the target may always work in non-stop mode even with "set
2320 non-stop off", in which case user_visible_resume_ptid could
2321 return a wildcard ptid. */
2322 if (target_is_non_stop_p ())
2323 return inferior_ptid
;
2325 return user_visible_resume_ptid (user_step
);
2328 /* Wrapper for target_resume, that handles infrun-specific
2332 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2334 struct thread_info
*tp
= inferior_thread ();
2336 /* Install inferior's terminal modes. */
2337 target_terminal_inferior ();
2339 /* Avoid confusing the next resume, if the next stop/resume
2340 happens to apply to another thread. */
2341 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2343 /* Advise target which signals may be handled silently.
2345 If we have removed breakpoints because we are stepping over one
2346 in-line (in any thread), we need to receive all signals to avoid
2347 accidentally skipping a breakpoint during execution of a signal
2350 Likewise if we're displaced stepping, otherwise a trap for a
2351 breakpoint in a signal handler might be confused with the
2352 displaced step finishing. We don't make the displaced_step_fixup
2353 step distinguish the cases instead, because:
2355 - a backtrace while stopped in the signal handler would show the
2356 scratch pad as frame older than the signal handler, instead of
2357 the real mainline code.
2359 - when the thread is later resumed, the signal handler would
2360 return to the scratch pad area, which would no longer be
2362 if (step_over_info_valid_p ()
2363 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2364 target_pass_signals (0, NULL
);
2366 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2368 target_resume (resume_ptid
, step
, sig
);
2371 /* Resume the inferior, but allow a QUIT. This is useful if the user
2372 wants to interrupt some lengthy single-stepping operation
2373 (for child processes, the SIGINT goes to the inferior, and so
2374 we get a SIGINT random_signal, but for remote debugging and perhaps
2375 other targets, that's not true).
2377 SIG is the signal to give the inferior (zero for none). */
2379 resume (enum gdb_signal sig
)
2381 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2382 struct regcache
*regcache
= get_current_regcache ();
2383 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2384 struct thread_info
*tp
= inferior_thread ();
2385 CORE_ADDR pc
= regcache_read_pc (regcache
);
2386 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2388 /* This represents the user's step vs continue request. When
2389 deciding whether "set scheduler-locking step" applies, it's the
2390 user's intention that counts. */
2391 const int user_step
= tp
->control
.stepping_command
;
2392 /* This represents what we'll actually request the target to do.
2393 This can decay from a step to a continue, if e.g., we need to
2394 implement single-stepping with breakpoints (software
2398 gdb_assert (!thread_is_in_step_over_chain (tp
));
2402 if (tp
->suspend
.waitstatus_pending_p
)
2408 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2409 fprintf_unfiltered (gdb_stdlog
,
2410 "infrun: resume: thread %s has pending wait status %s "
2411 "(currently_stepping=%d).\n",
2412 target_pid_to_str (tp
->ptid
), statstr
,
2413 currently_stepping (tp
));
2419 /* FIXME: What should we do if we are supposed to resume this
2420 thread with a signal? Maybe we should maintain a queue of
2421 pending signals to deliver. */
2422 if (sig
!= GDB_SIGNAL_0
)
2424 warning (_("Couldn't deliver signal %s to %s."),
2425 gdb_signal_to_name (sig
), target_pid_to_str (tp
->ptid
));
2428 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2429 discard_cleanups (old_cleanups
);
2431 if (target_can_async_p ())
2436 tp
->stepped_breakpoint
= 0;
2438 /* Depends on stepped_breakpoint. */
2439 step
= currently_stepping (tp
);
2441 if (current_inferior ()->waiting_for_vfork_done
)
2443 /* Don't try to single-step a vfork parent that is waiting for
2444 the child to get out of the shared memory region (by exec'ing
2445 or exiting). This is particularly important on software
2446 single-step archs, as the child process would trip on the
2447 software single step breakpoint inserted for the parent
2448 process. Since the parent will not actually execute any
2449 instruction until the child is out of the shared region (such
2450 are vfork's semantics), it is safe to simply continue it.
2451 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2452 the parent, and tell it to `keep_going', which automatically
2453 re-sets it stepping. */
2455 fprintf_unfiltered (gdb_stdlog
,
2456 "infrun: resume : clear step\n");
2461 fprintf_unfiltered (gdb_stdlog
,
2462 "infrun: resume (step=%d, signal=%s), "
2463 "trap_expected=%d, current thread [%s] at %s\n",
2464 step
, gdb_signal_to_symbol_string (sig
),
2465 tp
->control
.trap_expected
,
2466 target_pid_to_str (inferior_ptid
),
2467 paddress (gdbarch
, pc
));
2469 /* Normally, by the time we reach `resume', the breakpoints are either
2470 removed or inserted, as appropriate. The exception is if we're sitting
2471 at a permanent breakpoint; we need to step over it, but permanent
2472 breakpoints can't be removed. So we have to test for it here. */
2473 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2475 if (sig
!= GDB_SIGNAL_0
)
2477 /* We have a signal to pass to the inferior. The resume
2478 may, or may not take us to the signal handler. If this
2479 is a step, we'll need to stop in the signal handler, if
2480 there's one, (if the target supports stepping into
2481 handlers), or in the next mainline instruction, if
2482 there's no handler. If this is a continue, we need to be
2483 sure to run the handler with all breakpoints inserted.
2484 In all cases, set a breakpoint at the current address
2485 (where the handler returns to), and once that breakpoint
2486 is hit, resume skipping the permanent breakpoint. If
2487 that breakpoint isn't hit, then we've stepped into the
2488 signal handler (or hit some other event). We'll delete
2489 the step-resume breakpoint then. */
2492 fprintf_unfiltered (gdb_stdlog
,
2493 "infrun: resume: skipping permanent breakpoint, "
2494 "deliver signal first\n");
2496 clear_step_over_info ();
2497 tp
->control
.trap_expected
= 0;
2499 if (tp
->control
.step_resume_breakpoint
== NULL
)
2501 /* Set a "high-priority" step-resume, as we don't want
2502 user breakpoints at PC to trigger (again) when this
2504 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2505 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2507 tp
->step_after_step_resume_breakpoint
= step
;
2510 insert_breakpoints ();
2514 /* There's no signal to pass, we can go ahead and skip the
2515 permanent breakpoint manually. */
2517 fprintf_unfiltered (gdb_stdlog
,
2518 "infrun: resume: skipping permanent breakpoint\n");
2519 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2520 /* Update pc to reflect the new address from which we will
2521 execute instructions. */
2522 pc
= regcache_read_pc (regcache
);
2526 /* We've already advanced the PC, so the stepping part
2527 is done. Now we need to arrange for a trap to be
2528 reported to handle_inferior_event. Set a breakpoint
2529 at the current PC, and run to it. Don't update
2530 prev_pc, because if we end in
2531 switch_back_to_stepped_thread, we want the "expected
2532 thread advanced also" branch to be taken. IOW, we
2533 don't want this thread to step further from PC
2535 gdb_assert (!step_over_info_valid_p ());
2536 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2537 insert_breakpoints ();
2539 resume_ptid
= internal_resume_ptid (user_step
);
2540 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2541 discard_cleanups (old_cleanups
);
2548 /* If we have a breakpoint to step over, make sure to do a single
2549 step only. Same if we have software watchpoints. */
2550 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2551 tp
->control
.may_range_step
= 0;
2553 /* If enabled, step over breakpoints by executing a copy of the
2554 instruction at a different address.
2556 We can't use displaced stepping when we have a signal to deliver;
2557 the comments for displaced_step_prepare explain why. The
2558 comments in the handle_inferior event for dealing with 'random
2559 signals' explain what we do instead.
2561 We can't use displaced stepping when we are waiting for vfork_done
2562 event, displaced stepping breaks the vfork child similarly as single
2563 step software breakpoint. */
2564 if (tp
->control
.trap_expected
2565 && use_displaced_stepping (tp
)
2566 && !step_over_info_valid_p ()
2567 && sig
== GDB_SIGNAL_0
2568 && !current_inferior ()->waiting_for_vfork_done
)
2570 int prepared
= displaced_step_prepare (inferior_ptid
);
2575 fprintf_unfiltered (gdb_stdlog
,
2576 "Got placed in step-over queue\n");
2578 tp
->control
.trap_expected
= 0;
2579 discard_cleanups (old_cleanups
);
2582 else if (prepared
< 0)
2584 /* Fallback to stepping over the breakpoint in-line. */
2586 if (target_is_non_stop_p ())
2587 stop_all_threads ();
2589 set_step_over_info (get_regcache_aspace (regcache
),
2590 regcache_read_pc (regcache
), 0, tp
->global_num
);
2592 step
= maybe_software_singlestep (gdbarch
, pc
);
2594 insert_breakpoints ();
2596 else if (prepared
> 0)
2598 struct displaced_step_inferior_state
*displaced
;
2600 /* Update pc to reflect the new address from which we will
2601 execute instructions due to displaced stepping. */
2602 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2604 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2605 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2606 displaced
->step_closure
);
2610 /* Do we need to do it the hard way, w/temp breakpoints? */
2612 step
= maybe_software_singlestep (gdbarch
, pc
);
2614 /* Currently, our software single-step implementation leads to different
2615 results than hardware single-stepping in one situation: when stepping
2616 into delivering a signal which has an associated signal handler,
2617 hardware single-step will stop at the first instruction of the handler,
2618 while software single-step will simply skip execution of the handler.
2620 For now, this difference in behavior is accepted since there is no
2621 easy way to actually implement single-stepping into a signal handler
2622 without kernel support.
2624 However, there is one scenario where this difference leads to follow-on
2625 problems: if we're stepping off a breakpoint by removing all breakpoints
2626 and then single-stepping. In this case, the software single-step
2627 behavior means that even if there is a *breakpoint* in the signal
2628 handler, GDB still would not stop.
2630 Fortunately, we can at least fix this particular issue. We detect
2631 here the case where we are about to deliver a signal while software
2632 single-stepping with breakpoints removed. In this situation, we
2633 revert the decisions to remove all breakpoints and insert single-
2634 step breakpoints, and instead we install a step-resume breakpoint
2635 at the current address, deliver the signal without stepping, and
2636 once we arrive back at the step-resume breakpoint, actually step
2637 over the breakpoint we originally wanted to step over. */
2638 if (thread_has_single_step_breakpoints_set (tp
)
2639 && sig
!= GDB_SIGNAL_0
2640 && step_over_info_valid_p ())
2642 /* If we have nested signals or a pending signal is delivered
2643 immediately after a handler returns, might might already have
2644 a step-resume breakpoint set on the earlier handler. We cannot
2645 set another step-resume breakpoint; just continue on until the
2646 original breakpoint is hit. */
2647 if (tp
->control
.step_resume_breakpoint
== NULL
)
2649 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2650 tp
->step_after_step_resume_breakpoint
= 1;
2653 delete_single_step_breakpoints (tp
);
2655 clear_step_over_info ();
2656 tp
->control
.trap_expected
= 0;
2658 insert_breakpoints ();
2661 /* If STEP is set, it's a request to use hardware stepping
2662 facilities. But in that case, we should never
2663 use singlestep breakpoint. */
2664 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2666 /* Decide the set of threads to ask the target to resume. */
2667 if (tp
->control
.trap_expected
)
2669 /* We're allowing a thread to run past a breakpoint it has
2670 hit, either by single-stepping the thread with the breakpoint
2671 removed, or by displaced stepping, with the breakpoint inserted.
2672 In the former case, we need to single-step only this thread,
2673 and keep others stopped, as they can miss this breakpoint if
2674 allowed to run. That's not really a problem for displaced
2675 stepping, but, we still keep other threads stopped, in case
2676 another thread is also stopped for a breakpoint waiting for
2677 its turn in the displaced stepping queue. */
2678 resume_ptid
= inferior_ptid
;
2681 resume_ptid
= internal_resume_ptid (user_step
);
2683 if (execution_direction
!= EXEC_REVERSE
2684 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2686 /* There are two cases where we currently need to step a
2687 breakpoint instruction when we have a signal to deliver:
2689 - See handle_signal_stop where we handle random signals that
2690 could take out us out of the stepping range. Normally, in
2691 that case we end up continuing (instead of stepping) over the
2692 signal handler with a breakpoint at PC, but there are cases
2693 where we should _always_ single-step, even if we have a
2694 step-resume breakpoint, like when a software watchpoint is
2695 set. Assuming single-stepping and delivering a signal at the
2696 same time would takes us to the signal handler, then we could
2697 have removed the breakpoint at PC to step over it. However,
2698 some hardware step targets (like e.g., Mac OS) can't step
2699 into signal handlers, and for those, we need to leave the
2700 breakpoint at PC inserted, as otherwise if the handler
2701 recurses and executes PC again, it'll miss the breakpoint.
2702 So we leave the breakpoint inserted anyway, but we need to
2703 record that we tried to step a breakpoint instruction, so
2704 that adjust_pc_after_break doesn't end up confused.
2706 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2707 in one thread after another thread that was stepping had been
2708 momentarily paused for a step-over. When we re-resume the
2709 stepping thread, it may be resumed from that address with a
2710 breakpoint that hasn't trapped yet. Seen with
2711 gdb.threads/non-stop-fair-events.exp, on targets that don't
2712 do displaced stepping. */
2715 fprintf_unfiltered (gdb_stdlog
,
2716 "infrun: resume: [%s] stepped breakpoint\n",
2717 target_pid_to_str (tp
->ptid
));
2719 tp
->stepped_breakpoint
= 1;
2721 /* Most targets can step a breakpoint instruction, thus
2722 executing it normally. But if this one cannot, just
2723 continue and we will hit it anyway. */
2724 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2729 && tp
->control
.trap_expected
2730 && use_displaced_stepping (tp
)
2731 && !step_over_info_valid_p ())
2733 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2734 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2735 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2738 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2739 paddress (resume_gdbarch
, actual_pc
));
2740 read_memory (actual_pc
, buf
, sizeof (buf
));
2741 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2744 if (tp
->control
.may_range_step
)
2746 /* If we're resuming a thread with the PC out of the step
2747 range, then we're doing some nested/finer run control
2748 operation, like stepping the thread out of the dynamic
2749 linker or the displaced stepping scratch pad. We
2750 shouldn't have allowed a range step then. */
2751 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2754 do_target_resume (resume_ptid
, step
, sig
);
2756 discard_cleanups (old_cleanups
);
2763 /* Counter that tracks number of user visible stops. This can be used
2764 to tell whether a command has proceeded the inferior past the
2765 current location. This allows e.g., inferior function calls in
2766 breakpoint commands to not interrupt the command list. When the
2767 call finishes successfully, the inferior is standing at the same
2768 breakpoint as if nothing happened (and so we don't call
2770 static ULONGEST current_stop_id
;
2777 return current_stop_id
;
2780 /* Called when we report a user visible stop. */
2788 /* Clear out all variables saying what to do when inferior is continued.
2789 First do this, then set the ones you want, then call `proceed'. */
2792 clear_proceed_status_thread (struct thread_info
*tp
)
2795 fprintf_unfiltered (gdb_stdlog
,
2796 "infrun: clear_proceed_status_thread (%s)\n",
2797 target_pid_to_str (tp
->ptid
));
2799 /* If we're starting a new sequence, then the previous finished
2800 single-step is no longer relevant. */
2801 if (tp
->suspend
.waitstatus_pending_p
)
2803 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2806 fprintf_unfiltered (gdb_stdlog
,
2807 "infrun: clear_proceed_status: pending "
2808 "event of %s was a finished step. "
2810 target_pid_to_str (tp
->ptid
));
2812 tp
->suspend
.waitstatus_pending_p
= 0;
2813 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2815 else if (debug_infrun
)
2819 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2820 fprintf_unfiltered (gdb_stdlog
,
2821 "infrun: clear_proceed_status_thread: thread %s "
2822 "has pending wait status %s "
2823 "(currently_stepping=%d).\n",
2824 target_pid_to_str (tp
->ptid
), statstr
,
2825 currently_stepping (tp
));
2830 /* If this signal should not be seen by program, give it zero.
2831 Used for debugging signals. */
2832 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2833 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2835 thread_fsm_delete (tp
->thread_fsm
);
2836 tp
->thread_fsm
= NULL
;
2838 tp
->control
.trap_expected
= 0;
2839 tp
->control
.step_range_start
= 0;
2840 tp
->control
.step_range_end
= 0;
2841 tp
->control
.may_range_step
= 0;
2842 tp
->control
.step_frame_id
= null_frame_id
;
2843 tp
->control
.step_stack_frame_id
= null_frame_id
;
2844 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2845 tp
->control
.step_start_function
= NULL
;
2846 tp
->stop_requested
= 0;
2848 tp
->control
.stop_step
= 0;
2850 tp
->control
.proceed_to_finish
= 0;
2852 tp
->control
.command_interp
= NULL
;
2853 tp
->control
.stepping_command
= 0;
2855 /* Discard any remaining commands or status from previous stop. */
2856 bpstat_clear (&tp
->control
.stop_bpstat
);
2860 clear_proceed_status (int step
)
2862 /* With scheduler-locking replay, stop replaying other threads if we're
2863 not replaying the user-visible resume ptid.
2865 This is a convenience feature to not require the user to explicitly
2866 stop replaying the other threads. We're assuming that the user's
2867 intent is to resume tracing the recorded process. */
2868 if (!non_stop
&& scheduler_mode
== schedlock_replay
2869 && target_record_is_replaying (minus_one_ptid
)
2870 && !target_record_will_replay (user_visible_resume_ptid (step
),
2871 execution_direction
))
2872 target_record_stop_replaying ();
2876 struct thread_info
*tp
;
2879 resume_ptid
= user_visible_resume_ptid (step
);
2881 /* In all-stop mode, delete the per-thread status of all threads
2882 we're about to resume, implicitly and explicitly. */
2883 ALL_NON_EXITED_THREADS (tp
)
2885 if (!ptid_match (tp
->ptid
, resume_ptid
))
2887 clear_proceed_status_thread (tp
);
2891 if (!ptid_equal (inferior_ptid
, null_ptid
))
2893 struct inferior
*inferior
;
2897 /* If in non-stop mode, only delete the per-thread status of
2898 the current thread. */
2899 clear_proceed_status_thread (inferior_thread ());
2902 inferior
= current_inferior ();
2903 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2906 observer_notify_about_to_proceed ();
2909 /* Returns true if TP is still stopped at a breakpoint that needs
2910 stepping-over in order to make progress. If the breakpoint is gone
2911 meanwhile, we can skip the whole step-over dance. */
2914 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2916 if (tp
->stepping_over_breakpoint
)
2918 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2920 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2921 regcache_read_pc (regcache
))
2922 == ordinary_breakpoint_here
)
2925 tp
->stepping_over_breakpoint
= 0;
2931 /* Check whether thread TP still needs to start a step-over in order
2932 to make progress when resumed. Returns an bitwise or of enum
2933 step_over_what bits, indicating what needs to be stepped over. */
2935 static step_over_what
2936 thread_still_needs_step_over (struct thread_info
*tp
)
2938 step_over_what what
= 0;
2940 if (thread_still_needs_step_over_bp (tp
))
2941 what
|= STEP_OVER_BREAKPOINT
;
2943 if (tp
->stepping_over_watchpoint
2944 && !target_have_steppable_watchpoint
)
2945 what
|= STEP_OVER_WATCHPOINT
;
2950 /* Returns true if scheduler locking applies. STEP indicates whether
2951 we're about to do a step/next-like command to a thread. */
2954 schedlock_applies (struct thread_info
*tp
)
2956 return (scheduler_mode
== schedlock_on
2957 || (scheduler_mode
== schedlock_step
2958 && tp
->control
.stepping_command
)
2959 || (scheduler_mode
== schedlock_replay
2960 && target_record_will_replay (minus_one_ptid
,
2961 execution_direction
)));
2964 /* Basic routine for continuing the program in various fashions.
2966 ADDR is the address to resume at, or -1 for resume where stopped.
2967 SIGGNAL is the signal to give it, or 0 for none,
2968 or -1 for act according to how it stopped.
2969 STEP is nonzero if should trap after one instruction.
2970 -1 means return after that and print nothing.
2971 You should probably set various step_... variables
2972 before calling here, if you are stepping.
2974 You should call clear_proceed_status before calling proceed. */
2977 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2979 struct regcache
*regcache
;
2980 struct gdbarch
*gdbarch
;
2981 struct thread_info
*tp
;
2983 struct address_space
*aspace
;
2985 struct execution_control_state ecss
;
2986 struct execution_control_state
*ecs
= &ecss
;
2987 struct cleanup
*old_chain
;
2990 /* If we're stopped at a fork/vfork, follow the branch set by the
2991 "set follow-fork-mode" command; otherwise, we'll just proceed
2992 resuming the current thread. */
2993 if (!follow_fork ())
2995 /* The target for some reason decided not to resume. */
2997 if (target_can_async_p ())
2998 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3002 /* We'll update this if & when we switch to a new thread. */
3003 previous_inferior_ptid
= inferior_ptid
;
3005 regcache
= get_current_regcache ();
3006 gdbarch
= get_regcache_arch (regcache
);
3007 aspace
= get_regcache_aspace (regcache
);
3008 pc
= regcache_read_pc (regcache
);
3009 tp
= inferior_thread ();
3011 /* Fill in with reasonable starting values. */
3012 init_thread_stepping_state (tp
);
3014 gdb_assert (!thread_is_in_step_over_chain (tp
));
3016 if (addr
== (CORE_ADDR
) -1)
3019 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3020 && execution_direction
!= EXEC_REVERSE
)
3021 /* There is a breakpoint at the address we will resume at,
3022 step one instruction before inserting breakpoints so that
3023 we do not stop right away (and report a second hit at this
3026 Note, we don't do this in reverse, because we won't
3027 actually be executing the breakpoint insn anyway.
3028 We'll be (un-)executing the previous instruction. */
3029 tp
->stepping_over_breakpoint
= 1;
3030 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3031 && gdbarch_single_step_through_delay (gdbarch
,
3032 get_current_frame ()))
3033 /* We stepped onto an instruction that needs to be stepped
3034 again before re-inserting the breakpoint, do so. */
3035 tp
->stepping_over_breakpoint
= 1;
3039 regcache_write_pc (regcache
, addr
);
3042 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3043 tp
->suspend
.stop_signal
= siggnal
;
3045 /* Record the interpreter that issued the execution command that
3046 caused this thread to resume. If the top level interpreter is
3047 MI/async, and the execution command was a CLI command
3048 (next/step/etc.), we'll want to print stop event output to the MI
3049 console channel (the stepped-to line, etc.), as if the user
3050 entered the execution command on a real GDB console. */
3051 tp
->control
.command_interp
= command_interp ();
3053 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
3055 /* If an exception is thrown from this point on, make sure to
3056 propagate GDB's knowledge of the executing state to the
3057 frontend/user running state. */
3058 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
3060 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3061 threads (e.g., we might need to set threads stepping over
3062 breakpoints first), from the user/frontend's point of view, all
3063 threads in RESUME_PTID are now running. Unless we're calling an
3064 inferior function, as in that case we pretend the inferior
3065 doesn't run at all. */
3066 if (!tp
->control
.in_infcall
)
3067 set_running (resume_ptid
, 1);
3070 fprintf_unfiltered (gdb_stdlog
,
3071 "infrun: proceed (addr=%s, signal=%s)\n",
3072 paddress (gdbarch
, addr
),
3073 gdb_signal_to_symbol_string (siggnal
));
3075 annotate_starting ();
3077 /* Make sure that output from GDB appears before output from the
3079 gdb_flush (gdb_stdout
);
3081 /* In a multi-threaded task we may select another thread and
3082 then continue or step.
3084 But if a thread that we're resuming had stopped at a breakpoint,
3085 it will immediately cause another breakpoint stop without any
3086 execution (i.e. it will report a breakpoint hit incorrectly). So
3087 we must step over it first.
3089 Look for threads other than the current (TP) that reported a
3090 breakpoint hit and haven't been resumed yet since. */
3092 /* If scheduler locking applies, we can avoid iterating over all
3094 if (!non_stop
&& !schedlock_applies (tp
))
3096 struct thread_info
*current
= tp
;
3098 ALL_NON_EXITED_THREADS (tp
)
3100 /* Ignore the current thread here. It's handled
3105 /* Ignore threads of processes we're not resuming. */
3106 if (!ptid_match (tp
->ptid
, resume_ptid
))
3109 if (!thread_still_needs_step_over (tp
))
3112 gdb_assert (!thread_is_in_step_over_chain (tp
));
3115 fprintf_unfiltered (gdb_stdlog
,
3116 "infrun: need to step-over [%s] first\n",
3117 target_pid_to_str (tp
->ptid
));
3119 thread_step_over_chain_enqueue (tp
);
3125 /* Enqueue the current thread last, so that we move all other
3126 threads over their breakpoints first. */
3127 if (tp
->stepping_over_breakpoint
)
3128 thread_step_over_chain_enqueue (tp
);
3130 /* If the thread isn't started, we'll still need to set its prev_pc,
3131 so that switch_back_to_stepped_thread knows the thread hasn't
3132 advanced. Must do this before resuming any thread, as in
3133 all-stop/remote, once we resume we can't send any other packet
3134 until the target stops again. */
3135 tp
->prev_pc
= regcache_read_pc (regcache
);
3137 started
= start_step_over ();
3139 if (step_over_info_valid_p ())
3141 /* Either this thread started a new in-line step over, or some
3142 other thread was already doing one. In either case, don't
3143 resume anything else until the step-over is finished. */
3145 else if (started
&& !target_is_non_stop_p ())
3147 /* A new displaced stepping sequence was started. In all-stop,
3148 we can't talk to the target anymore until it next stops. */
3150 else if (!non_stop
&& target_is_non_stop_p ())
3152 /* In all-stop, but the target is always in non-stop mode.
3153 Start all other threads that are implicitly resumed too. */
3154 ALL_NON_EXITED_THREADS (tp
)
3156 /* Ignore threads of processes we're not resuming. */
3157 if (!ptid_match (tp
->ptid
, resume_ptid
))
3163 fprintf_unfiltered (gdb_stdlog
,
3164 "infrun: proceed: [%s] resumed\n",
3165 target_pid_to_str (tp
->ptid
));
3166 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3170 if (thread_is_in_step_over_chain (tp
))
3173 fprintf_unfiltered (gdb_stdlog
,
3174 "infrun: proceed: [%s] needs step-over\n",
3175 target_pid_to_str (tp
->ptid
));
3180 fprintf_unfiltered (gdb_stdlog
,
3181 "infrun: proceed: resuming %s\n",
3182 target_pid_to_str (tp
->ptid
));
3184 reset_ecs (ecs
, tp
);
3185 switch_to_thread (tp
->ptid
);
3186 keep_going_pass_signal (ecs
);
3187 if (!ecs
->wait_some_more
)
3188 error (_("Command aborted."));
3191 else if (!tp
->resumed
&& !thread_is_in_step_over_chain (tp
))
3193 /* The thread wasn't started, and isn't queued, run it now. */
3194 reset_ecs (ecs
, tp
);
3195 switch_to_thread (tp
->ptid
);
3196 keep_going_pass_signal (ecs
);
3197 if (!ecs
->wait_some_more
)
3198 error (_("Command aborted."));
3201 discard_cleanups (old_chain
);
3203 /* Tell the event loop to wait for it to stop. If the target
3204 supports asynchronous execution, it'll do this from within
3206 if (!target_can_async_p ())
3207 mark_async_event_handler (infrun_async_inferior_event_token
);
3211 /* Start remote-debugging of a machine over a serial link. */
3214 start_remote (int from_tty
)
3216 struct inferior
*inferior
;
3218 inferior
= current_inferior ();
3219 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3221 /* Always go on waiting for the target, regardless of the mode. */
3222 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3223 indicate to wait_for_inferior that a target should timeout if
3224 nothing is returned (instead of just blocking). Because of this,
3225 targets expecting an immediate response need to, internally, set
3226 things up so that the target_wait() is forced to eventually
3228 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3229 differentiate to its caller what the state of the target is after
3230 the initial open has been performed. Here we're assuming that
3231 the target has stopped. It should be possible to eventually have
3232 target_open() return to the caller an indication that the target
3233 is currently running and GDB state should be set to the same as
3234 for an async run. */
3235 wait_for_inferior ();
3237 /* Now that the inferior has stopped, do any bookkeeping like
3238 loading shared libraries. We want to do this before normal_stop,
3239 so that the displayed frame is up to date. */
3240 post_create_inferior (¤t_target
, from_tty
);
3245 /* Initialize static vars when a new inferior begins. */
3248 init_wait_for_inferior (void)
3250 /* These are meaningless until the first time through wait_for_inferior. */
3252 breakpoint_init_inferior (inf_starting
);
3254 clear_proceed_status (0);
3256 target_last_wait_ptid
= minus_one_ptid
;
3258 previous_inferior_ptid
= inferior_ptid
;
3260 /* Discard any skipped inlined frames. */
3261 clear_inline_frame_state (minus_one_ptid
);
3266 static void handle_inferior_event (struct execution_control_state
*ecs
);
3268 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3269 struct execution_control_state
*ecs
);
3270 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3271 struct execution_control_state
*ecs
);
3272 static void handle_signal_stop (struct execution_control_state
*ecs
);
3273 static void check_exception_resume (struct execution_control_state
*,
3274 struct frame_info
*);
3276 static void end_stepping_range (struct execution_control_state
*ecs
);
3277 static void stop_waiting (struct execution_control_state
*ecs
);
3278 static void keep_going (struct execution_control_state
*ecs
);
3279 static void process_event_stop_test (struct execution_control_state
*ecs
);
3280 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3282 /* Callback for iterate over threads. If the thread is stopped, but
3283 the user/frontend doesn't know about that yet, go through
3284 normal_stop, as if the thread had just stopped now. ARG points at
3285 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
3286 ptid_is_pid(PTID) is true, applies to all threads of the process
3287 pointed at by PTID. Otherwise, apply only to the thread pointed by
3291 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
3293 ptid_t ptid
= * (ptid_t
*) arg
;
3295 if ((ptid_equal (info
->ptid
, ptid
)
3296 || ptid_equal (minus_one_ptid
, ptid
)
3297 || (ptid_is_pid (ptid
)
3298 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
3299 && is_running (info
->ptid
)
3300 && !is_executing (info
->ptid
))
3302 struct cleanup
*old_chain
;
3303 struct execution_control_state ecss
;
3304 struct execution_control_state
*ecs
= &ecss
;
3306 memset (ecs
, 0, sizeof (*ecs
));
3308 old_chain
= make_cleanup_restore_current_thread ();
3310 overlay_cache_invalid
= 1;
3311 /* Flush target cache before starting to handle each event.
3312 Target was running and cache could be stale. This is just a
3313 heuristic. Running threads may modify target memory, but we
3314 don't get any event. */
3315 target_dcache_invalidate ();
3317 /* Go through handle_inferior_event/normal_stop, so we always
3318 have consistent output as if the stop event had been
3320 ecs
->ptid
= info
->ptid
;
3321 ecs
->event_thread
= info
;
3322 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
3323 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
3325 handle_inferior_event (ecs
);
3327 if (!ecs
->wait_some_more
)
3329 /* Cancel any running execution command. */
3330 thread_cancel_execution_command (info
);
3335 do_cleanups (old_chain
);
3341 /* This function is attached as a "thread_stop_requested" observer.
3342 Cleanup local state that assumed the PTID was to be resumed, and
3343 report the stop to the frontend. */
3346 infrun_thread_stop_requested (ptid_t ptid
)
3348 struct thread_info
*tp
;
3350 /* PTID was requested to stop. Remove matching threads from the
3351 step-over queue, so we don't try to resume them
3353 ALL_NON_EXITED_THREADS (tp
)
3354 if (ptid_match (tp
->ptid
, ptid
))
3356 if (thread_is_in_step_over_chain (tp
))
3357 thread_step_over_chain_remove (tp
);
3360 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
3364 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3366 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3367 nullify_last_target_wait_ptid ();
3370 /* Delete the step resume, single-step and longjmp/exception resume
3371 breakpoints of TP. */
3374 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3376 delete_step_resume_breakpoint (tp
);
3377 delete_exception_resume_breakpoint (tp
);
3378 delete_single_step_breakpoints (tp
);
3381 /* If the target still has execution, call FUNC for each thread that
3382 just stopped. In all-stop, that's all the non-exited threads; in
3383 non-stop, that's the current thread, only. */
3385 typedef void (*for_each_just_stopped_thread_callback_func
)
3386 (struct thread_info
*tp
);
3389 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3391 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3394 if (target_is_non_stop_p ())
3396 /* If in non-stop mode, only the current thread stopped. */
3397 func (inferior_thread ());
3401 struct thread_info
*tp
;
3403 /* In all-stop mode, all threads have stopped. */
3404 ALL_NON_EXITED_THREADS (tp
)
3411 /* Delete the step resume and longjmp/exception resume breakpoints of
3412 the threads that just stopped. */
3415 delete_just_stopped_threads_infrun_breakpoints (void)
3417 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3420 /* Delete the single-step breakpoints of the threads that just
3424 delete_just_stopped_threads_single_step_breakpoints (void)
3426 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3429 /* A cleanup wrapper. */
3432 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3434 delete_just_stopped_threads_infrun_breakpoints ();
3440 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3441 const struct target_waitstatus
*ws
)
3443 char *status_string
= target_waitstatus_to_string (ws
);
3444 struct ui_file
*tmp_stream
= mem_fileopen ();
3447 /* The text is split over several lines because it was getting too long.
3448 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3449 output as a unit; we want only one timestamp printed if debug_timestamp
3452 fprintf_unfiltered (tmp_stream
,
3453 "infrun: target_wait (%d.%ld.%ld",
3454 ptid_get_pid (waiton_ptid
),
3455 ptid_get_lwp (waiton_ptid
),
3456 ptid_get_tid (waiton_ptid
));
3457 if (ptid_get_pid (waiton_ptid
) != -1)
3458 fprintf_unfiltered (tmp_stream
,
3459 " [%s]", target_pid_to_str (waiton_ptid
));
3460 fprintf_unfiltered (tmp_stream
, ", status) =\n");
3461 fprintf_unfiltered (tmp_stream
,
3462 "infrun: %d.%ld.%ld [%s],\n",
3463 ptid_get_pid (result_ptid
),
3464 ptid_get_lwp (result_ptid
),
3465 ptid_get_tid (result_ptid
),
3466 target_pid_to_str (result_ptid
));
3467 fprintf_unfiltered (tmp_stream
,
3471 text
= ui_file_xstrdup (tmp_stream
, NULL
);
3473 /* This uses %s in part to handle %'s in the text, but also to avoid
3474 a gcc error: the format attribute requires a string literal. */
3475 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
3477 xfree (status_string
);
3479 ui_file_delete (tmp_stream
);
3482 /* Select a thread at random, out of those which are resumed and have
3485 static struct thread_info
*
3486 random_pending_event_thread (ptid_t waiton_ptid
)
3488 struct thread_info
*event_tp
;
3490 int random_selector
;
3492 /* First see how many events we have. Count only resumed threads
3493 that have an event pending. */
3494 ALL_NON_EXITED_THREADS (event_tp
)
3495 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3496 && event_tp
->resumed
3497 && event_tp
->suspend
.waitstatus_pending_p
)
3500 if (num_events
== 0)
3503 /* Now randomly pick a thread out of those that have had events. */
3504 random_selector
= (int)
3505 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3507 if (debug_infrun
&& num_events
> 1)
3508 fprintf_unfiltered (gdb_stdlog
,
3509 "infrun: Found %d events, selecting #%d\n",
3510 num_events
, random_selector
);
3512 /* Select the Nth thread that has had an event. */
3513 ALL_NON_EXITED_THREADS (event_tp
)
3514 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3515 && event_tp
->resumed
3516 && event_tp
->suspend
.waitstatus_pending_p
)
3517 if (random_selector
-- == 0)
3523 /* Wrapper for target_wait that first checks whether threads have
3524 pending statuses to report before actually asking the target for
3528 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3531 struct thread_info
*tp
;
3533 /* First check if there is a resumed thread with a wait status
3535 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
3537 tp
= random_pending_event_thread (ptid
);
3542 fprintf_unfiltered (gdb_stdlog
,
3543 "infrun: Waiting for specific thread %s.\n",
3544 target_pid_to_str (ptid
));
3546 /* We have a specific thread to check. */
3547 tp
= find_thread_ptid (ptid
);
3548 gdb_assert (tp
!= NULL
);
3549 if (!tp
->suspend
.waitstatus_pending_p
)
3554 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3555 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3557 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
3558 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3562 pc
= regcache_read_pc (regcache
);
3564 if (pc
!= tp
->suspend
.stop_pc
)
3567 fprintf_unfiltered (gdb_stdlog
,
3568 "infrun: PC of %s changed. was=%s, now=%s\n",
3569 target_pid_to_str (tp
->ptid
),
3570 paddress (gdbarch
, tp
->prev_pc
),
3571 paddress (gdbarch
, pc
));
3574 else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache
), pc
))
3577 fprintf_unfiltered (gdb_stdlog
,
3578 "infrun: previous breakpoint of %s, at %s gone\n",
3579 target_pid_to_str (tp
->ptid
),
3580 paddress (gdbarch
, pc
));
3588 fprintf_unfiltered (gdb_stdlog
,
3589 "infrun: pending event of %s cancelled.\n",
3590 target_pid_to_str (tp
->ptid
));
3592 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3593 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3603 statstr
= target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3604 fprintf_unfiltered (gdb_stdlog
,
3605 "infrun: Using pending wait status %s for %s.\n",
3607 target_pid_to_str (tp
->ptid
));
3611 /* Now that we've selected our final event LWP, un-adjust its PC
3612 if it was a software breakpoint (and the target doesn't
3613 always adjust the PC itself). */
3614 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3615 && !target_supports_stopped_by_sw_breakpoint ())
3617 struct regcache
*regcache
;
3618 struct gdbarch
*gdbarch
;
3621 regcache
= get_thread_regcache (tp
->ptid
);
3622 gdbarch
= get_regcache_arch (regcache
);
3624 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3629 pc
= regcache_read_pc (regcache
);
3630 regcache_write_pc (regcache
, pc
+ decr_pc
);
3634 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3635 *status
= tp
->suspend
.waitstatus
;
3636 tp
->suspend
.waitstatus_pending_p
= 0;
3638 /* Wake up the event loop again, until all pending events are
3640 if (target_is_async_p ())
3641 mark_async_event_handler (infrun_async_inferior_event_token
);
3645 /* But if we don't find one, we'll have to wait. */
3647 if (deprecated_target_wait_hook
)
3648 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3650 event_ptid
= target_wait (ptid
, status
, options
);
3655 /* Prepare and stabilize the inferior for detaching it. E.g.,
3656 detaching while a thread is displaced stepping is a recipe for
3657 crashing it, as nothing would readjust the PC out of the scratch
3661 prepare_for_detach (void)
3663 struct inferior
*inf
= current_inferior ();
3664 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3665 struct cleanup
*old_chain_1
;
3666 struct displaced_step_inferior_state
*displaced
;
3668 displaced
= get_displaced_stepping_state (inf
->pid
);
3670 /* Is any thread of this process displaced stepping? If not,
3671 there's nothing else to do. */
3672 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3676 fprintf_unfiltered (gdb_stdlog
,
3677 "displaced-stepping in-process while detaching");
3679 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3682 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3684 struct cleanup
*old_chain_2
;
3685 struct execution_control_state ecss
;
3686 struct execution_control_state
*ecs
;
3689 memset (ecs
, 0, sizeof (*ecs
));
3691 overlay_cache_invalid
= 1;
3692 /* Flush target cache before starting to handle each event.
3693 Target was running and cache could be stale. This is just a
3694 heuristic. Running threads may modify target memory, but we
3695 don't get any event. */
3696 target_dcache_invalidate ();
3698 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3701 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3703 /* If an error happens while handling the event, propagate GDB's
3704 knowledge of the executing state to the frontend/user running
3706 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3709 /* Now figure out what to do with the result of the result. */
3710 handle_inferior_event (ecs
);
3712 /* No error, don't finish the state yet. */
3713 discard_cleanups (old_chain_2
);
3715 /* Breakpoints and watchpoints are not installed on the target
3716 at this point, and signals are passed directly to the
3717 inferior, so this must mean the process is gone. */
3718 if (!ecs
->wait_some_more
)
3720 discard_cleanups (old_chain_1
);
3721 error (_("Program exited while detaching"));
3725 discard_cleanups (old_chain_1
);
3728 /* Wait for control to return from inferior to debugger.
3730 If inferior gets a signal, we may decide to start it up again
3731 instead of returning. That is why there is a loop in this function.
3732 When this function actually returns it means the inferior
3733 should be left stopped and GDB should read more commands. */
3736 wait_for_inferior (void)
3738 struct cleanup
*old_cleanups
;
3739 struct cleanup
*thread_state_chain
;
3743 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3746 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3749 /* If an error happens while handling the event, propagate GDB's
3750 knowledge of the executing state to the frontend/user running
3752 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3756 struct execution_control_state ecss
;
3757 struct execution_control_state
*ecs
= &ecss
;
3758 ptid_t waiton_ptid
= minus_one_ptid
;
3760 memset (ecs
, 0, sizeof (*ecs
));
3762 overlay_cache_invalid
= 1;
3764 /* Flush target cache before starting to handle each event.
3765 Target was running and cache could be stale. This is just a
3766 heuristic. Running threads may modify target memory, but we
3767 don't get any event. */
3768 target_dcache_invalidate ();
3770 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3773 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3775 /* Now figure out what to do with the result of the result. */
3776 handle_inferior_event (ecs
);
3778 if (!ecs
->wait_some_more
)
3782 /* No error, don't finish the state yet. */
3783 discard_cleanups (thread_state_chain
);
3785 do_cleanups (old_cleanups
);
3788 /* Cleanup that reinstalls the readline callback handler, if the
3789 target is running in the background. If while handling the target
3790 event something triggered a secondary prompt, like e.g., a
3791 pagination prompt, we'll have removed the callback handler (see
3792 gdb_readline_wrapper_line). Need to do this as we go back to the
3793 event loop, ready to process further input. Note this has no
3794 effect if the handler hasn't actually been removed, because calling
3795 rl_callback_handler_install resets the line buffer, thus losing
3799 reinstall_readline_callback_handler_cleanup (void *arg
)
3801 struct ui
*ui
= current_ui
;
3805 /* We're not going back to the top level event loop yet. Don't
3806 install the readline callback, as it'd prep the terminal,
3807 readline-style (raw, noecho) (e.g., --batch). We'll install
3808 it the next time the prompt is displayed, when we're ready
3813 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3814 gdb_rl_callback_handler_reinstall ();
3817 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3818 that's just the event thread. In all-stop, that's all threads. */
3821 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3823 struct thread_info
*thr
= ecs
->event_thread
;
3825 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3826 thread_fsm_clean_up (thr
->thread_fsm
);
3830 ALL_NON_EXITED_THREADS (thr
)
3832 if (thr
->thread_fsm
== NULL
)
3834 if (thr
== ecs
->event_thread
)
3837 switch_to_thread (thr
->ptid
);
3838 thread_fsm_clean_up (thr
->thread_fsm
);
3841 if (ecs
->event_thread
!= NULL
)
3842 switch_to_thread (ecs
->event_thread
->ptid
);
3846 /* Helper for all_uis_check_sync_execution_done that works on the
3850 check_curr_ui_sync_execution_done (void)
3852 struct ui
*ui
= current_ui
;
3854 if (ui
->prompt_state
== PROMPT_NEEDED
3856 && !gdb_in_secondary_prompt_p (ui
))
3858 target_terminal_ours ();
3859 observer_notify_sync_execution_done ();
3866 all_uis_check_sync_execution_done (void)
3868 struct switch_thru_all_uis state
;
3870 SWITCH_THRU_ALL_UIS (state
)
3872 check_curr_ui_sync_execution_done ();
3879 all_uis_on_sync_execution_starting (void)
3881 struct switch_thru_all_uis state
;
3883 SWITCH_THRU_ALL_UIS (state
)
3885 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3886 async_disable_stdin ();
3890 /* A cleanup that restores the execution direction to the value saved
3894 restore_execution_direction (void *arg
)
3896 enum exec_direction_kind
*save_exec_dir
= (enum exec_direction_kind
*) arg
;
3898 execution_direction
= *save_exec_dir
;
3901 /* Asynchronous version of wait_for_inferior. It is called by the
3902 event loop whenever a change of state is detected on the file
3903 descriptor corresponding to the target. It can be called more than
3904 once to complete a single execution command. In such cases we need
3905 to keep the state in a global variable ECSS. If it is the last time
3906 that this function is called for a single execution command, then
3907 report to the user that the inferior has stopped, and do the
3908 necessary cleanups. */
3911 fetch_inferior_event (void *client_data
)
3913 struct execution_control_state ecss
;
3914 struct execution_control_state
*ecs
= &ecss
;
3915 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3916 struct cleanup
*ts_old_chain
;
3917 enum exec_direction_kind save_exec_dir
= execution_direction
;
3919 ptid_t waiton_ptid
= minus_one_ptid
;
3921 memset (ecs
, 0, sizeof (*ecs
));
3923 /* Events are always processed with the main UI as current UI. This
3924 way, warnings, debug output, etc. are always consistently sent to
3925 the main console. */
3926 make_cleanup (restore_ui_cleanup
, current_ui
);
3927 current_ui
= main_ui
;
3929 /* End up with readline processing input, if necessary. */
3930 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3932 /* We're handling a live event, so make sure we're doing live
3933 debugging. If we're looking at traceframes while the target is
3934 running, we're going to need to get back to that mode after
3935 handling the event. */
3938 make_cleanup_restore_current_traceframe ();
3939 set_current_traceframe (-1);
3943 /* In non-stop mode, the user/frontend should not notice a thread
3944 switch due to internal events. Make sure we reverse to the
3945 user selected thread and frame after handling the event and
3946 running any breakpoint commands. */
3947 make_cleanup_restore_current_thread ();
3949 overlay_cache_invalid
= 1;
3950 /* Flush target cache before starting to handle each event. Target
3951 was running and cache could be stale. This is just a heuristic.
3952 Running threads may modify target memory, but we don't get any
3954 target_dcache_invalidate ();
3956 make_cleanup (restore_execution_direction
, &save_exec_dir
);
3957 execution_direction
= target_execution_direction ();
3959 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3960 target_can_async_p () ? TARGET_WNOHANG
: 0);
3963 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3965 /* If an error happens while handling the event, propagate GDB's
3966 knowledge of the executing state to the frontend/user running
3968 if (!target_is_non_stop_p ())
3969 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3971 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3973 /* Get executed before make_cleanup_restore_current_thread above to apply
3974 still for the thread which has thrown the exception. */
3975 make_bpstat_clear_actions_cleanup ();
3977 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3979 /* Now figure out what to do with the result of the result. */
3980 handle_inferior_event (ecs
);
3982 if (!ecs
->wait_some_more
)
3984 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3985 int should_stop
= 1;
3986 struct thread_info
*thr
= ecs
->event_thread
;
3987 int should_notify_stop
= 1;
3989 delete_just_stopped_threads_infrun_breakpoints ();
3993 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3995 if (thread_fsm
!= NULL
)
3996 should_stop
= thread_fsm_should_stop (thread_fsm
);
4005 clean_up_just_stopped_threads_fsms (ecs
);
4007 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
4010 = thread_fsm_should_notify_stop (thr
->thread_fsm
);
4013 if (should_notify_stop
)
4017 /* We may not find an inferior if this was a process exit. */
4018 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
4019 proceeded
= normal_stop ();
4023 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
4030 /* No error, don't finish the thread states yet. */
4031 discard_cleanups (ts_old_chain
);
4033 /* Revert thread and frame. */
4034 do_cleanups (old_chain
);
4036 /* If a UI was in sync execution mode, and now isn't, restore its
4037 prompt (a synchronous execution command has finished, and we're
4038 ready for input). */
4039 all_uis_check_sync_execution_done ();
4042 && exec_done_display_p
4043 && (ptid_equal (inferior_ptid
, null_ptid
)
4044 || !is_running (inferior_ptid
)))
4045 printf_unfiltered (_("completed.\n"));
4048 /* Record the frame and location we're currently stepping through. */
4050 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
4052 struct thread_info
*tp
= inferior_thread ();
4054 tp
->control
.step_frame_id
= get_frame_id (frame
);
4055 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4057 tp
->current_symtab
= sal
.symtab
;
4058 tp
->current_line
= sal
.line
;
4061 /* Clear context switchable stepping state. */
4064 init_thread_stepping_state (struct thread_info
*tss
)
4066 tss
->stepped_breakpoint
= 0;
4067 tss
->stepping_over_breakpoint
= 0;
4068 tss
->stepping_over_watchpoint
= 0;
4069 tss
->step_after_step_resume_breakpoint
= 0;
4072 /* Set the cached copy of the last ptid/waitstatus. */
4075 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
4077 target_last_wait_ptid
= ptid
;
4078 target_last_waitstatus
= status
;
4081 /* Return the cached copy of the last pid/waitstatus returned by
4082 target_wait()/deprecated_target_wait_hook(). The data is actually
4083 cached by handle_inferior_event(), which gets called immediately
4084 after target_wait()/deprecated_target_wait_hook(). */
4087 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
4089 *ptidp
= target_last_wait_ptid
;
4090 *status
= target_last_waitstatus
;
4094 nullify_last_target_wait_ptid (void)
4096 target_last_wait_ptid
= minus_one_ptid
;
4099 /* Switch thread contexts. */
4102 context_switch (ptid_t ptid
)
4104 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
4106 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
4107 target_pid_to_str (inferior_ptid
));
4108 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
4109 target_pid_to_str (ptid
));
4112 switch_to_thread (ptid
);
4115 /* If the target can't tell whether we've hit breakpoints
4116 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4117 check whether that could have been caused by a breakpoint. If so,
4118 adjust the PC, per gdbarch_decr_pc_after_break. */
4121 adjust_pc_after_break (struct thread_info
*thread
,
4122 struct target_waitstatus
*ws
)
4124 struct regcache
*regcache
;
4125 struct gdbarch
*gdbarch
;
4126 struct address_space
*aspace
;
4127 CORE_ADDR breakpoint_pc
, decr_pc
;
4129 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4130 we aren't, just return.
4132 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4133 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4134 implemented by software breakpoints should be handled through the normal
4137 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4138 different signals (SIGILL or SIGEMT for instance), but it is less
4139 clear where the PC is pointing afterwards. It may not match
4140 gdbarch_decr_pc_after_break. I don't know any specific target that
4141 generates these signals at breakpoints (the code has been in GDB since at
4142 least 1992) so I can not guess how to handle them here.
4144 In earlier versions of GDB, a target with
4145 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4146 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4147 target with both of these set in GDB history, and it seems unlikely to be
4148 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4150 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4153 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4156 /* In reverse execution, when a breakpoint is hit, the instruction
4157 under it has already been de-executed. The reported PC always
4158 points at the breakpoint address, so adjusting it further would
4159 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4162 B1 0x08000000 : INSN1
4163 B2 0x08000001 : INSN2
4165 PC -> 0x08000003 : INSN4
4167 Say you're stopped at 0x08000003 as above. Reverse continuing
4168 from that point should hit B2 as below. Reading the PC when the
4169 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4170 been de-executed already.
4172 B1 0x08000000 : INSN1
4173 B2 PC -> 0x08000001 : INSN2
4177 We can't apply the same logic as for forward execution, because
4178 we would wrongly adjust the PC to 0x08000000, since there's a
4179 breakpoint at PC - 1. We'd then report a hit on B1, although
4180 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4182 if (execution_direction
== EXEC_REVERSE
)
4185 /* If the target can tell whether the thread hit a SW breakpoint,
4186 trust it. Targets that can tell also adjust the PC
4188 if (target_supports_stopped_by_sw_breakpoint ())
4191 /* Note that relying on whether a breakpoint is planted in memory to
4192 determine this can fail. E.g,. the breakpoint could have been
4193 removed since. Or the thread could have been told to step an
4194 instruction the size of a breakpoint instruction, and only
4195 _after_ was a breakpoint inserted at its address. */
4197 /* If this target does not decrement the PC after breakpoints, then
4198 we have nothing to do. */
4199 regcache
= get_thread_regcache (thread
->ptid
);
4200 gdbarch
= get_regcache_arch (regcache
);
4202 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4206 aspace
= get_regcache_aspace (regcache
);
4208 /* Find the location where (if we've hit a breakpoint) the
4209 breakpoint would be. */
4210 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4212 /* If the target can't tell whether a software breakpoint triggered,
4213 fallback to figuring it out based on breakpoints we think were
4214 inserted in the target, and on whether the thread was stepped or
4217 /* Check whether there actually is a software breakpoint inserted at
4220 If in non-stop mode, a race condition is possible where we've
4221 removed a breakpoint, but stop events for that breakpoint were
4222 already queued and arrive later. To suppress those spurious
4223 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4224 and retire them after a number of stop events are reported. Note
4225 this is an heuristic and can thus get confused. The real fix is
4226 to get the "stopped by SW BP and needs adjustment" info out of
4227 the target/kernel (and thus never reach here; see above). */
4228 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4229 || (target_is_non_stop_p ()
4230 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4232 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4234 if (record_full_is_used ())
4235 record_full_gdb_operation_disable_set ();
4237 /* When using hardware single-step, a SIGTRAP is reported for both
4238 a completed single-step and a software breakpoint. Need to
4239 differentiate between the two, as the latter needs adjusting
4240 but the former does not.
4242 The SIGTRAP can be due to a completed hardware single-step only if
4243 - we didn't insert software single-step breakpoints
4244 - this thread is currently being stepped
4246 If any of these events did not occur, we must have stopped due
4247 to hitting a software breakpoint, and have to back up to the
4250 As a special case, we could have hardware single-stepped a
4251 software breakpoint. In this case (prev_pc == breakpoint_pc),
4252 we also need to back up to the breakpoint address. */
4254 if (thread_has_single_step_breakpoints_set (thread
)
4255 || !currently_stepping (thread
)
4256 || (thread
->stepped_breakpoint
4257 && thread
->prev_pc
== breakpoint_pc
))
4258 regcache_write_pc (regcache
, breakpoint_pc
);
4260 do_cleanups (old_cleanups
);
4265 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4267 for (frame
= get_prev_frame (frame
);
4269 frame
= get_prev_frame (frame
))
4271 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4273 if (get_frame_type (frame
) != INLINE_FRAME
)
4280 /* Auxiliary function that handles syscall entry/return events.
4281 It returns 1 if the inferior should keep going (and GDB
4282 should ignore the event), or 0 if the event deserves to be
4286 handle_syscall_event (struct execution_control_state
*ecs
)
4288 struct regcache
*regcache
;
4291 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4292 context_switch (ecs
->ptid
);
4294 regcache
= get_thread_regcache (ecs
->ptid
);
4295 syscall_number
= ecs
->ws
.value
.syscall_number
;
4296 stop_pc
= regcache_read_pc (regcache
);
4298 if (catch_syscall_enabled () > 0
4299 && catching_syscall_number (syscall_number
) > 0)
4302 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4305 ecs
->event_thread
->control
.stop_bpstat
4306 = bpstat_stop_status (get_regcache_aspace (regcache
),
4307 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4309 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4311 /* Catchpoint hit. */
4316 /* If no catchpoint triggered for this, then keep going. */
4321 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4324 fill_in_stop_func (struct gdbarch
*gdbarch
,
4325 struct execution_control_state
*ecs
)
4327 if (!ecs
->stop_func_filled_in
)
4329 /* Don't care about return value; stop_func_start and stop_func_name
4330 will both be 0 if it doesn't work. */
4331 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4332 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4333 ecs
->stop_func_start
4334 += gdbarch_deprecated_function_start_offset (gdbarch
);
4336 if (gdbarch_skip_entrypoint_p (gdbarch
))
4337 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4338 ecs
->stop_func_start
);
4340 ecs
->stop_func_filled_in
= 1;
4345 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4347 static enum stop_kind
4348 get_inferior_stop_soon (ptid_t ptid
)
4350 struct inferior
*inf
= find_inferior_ptid (ptid
);
4352 gdb_assert (inf
!= NULL
);
4353 return inf
->control
.stop_soon
;
4356 /* Wait for one event. Store the resulting waitstatus in WS, and
4357 return the event ptid. */
4360 wait_one (struct target_waitstatus
*ws
)
4363 ptid_t wait_ptid
= minus_one_ptid
;
4365 overlay_cache_invalid
= 1;
4367 /* Flush target cache before starting to handle each event.
4368 Target was running and cache could be stale. This is just a
4369 heuristic. Running threads may modify target memory, but we
4370 don't get any event. */
4371 target_dcache_invalidate ();
4373 if (deprecated_target_wait_hook
)
4374 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4376 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4379 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4384 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4385 instead of the current thread. */
4386 #define THREAD_STOPPED_BY(REASON) \
4388 thread_stopped_by_ ## REASON (ptid_t ptid) \
4390 struct cleanup *old_chain; \
4393 old_chain = save_inferior_ptid (); \
4394 inferior_ptid = ptid; \
4396 res = target_stopped_by_ ## REASON (); \
4398 do_cleanups (old_chain); \
4403 /* Generate thread_stopped_by_watchpoint. */
4404 THREAD_STOPPED_BY (watchpoint
)
4405 /* Generate thread_stopped_by_sw_breakpoint. */
4406 THREAD_STOPPED_BY (sw_breakpoint
)
4407 /* Generate thread_stopped_by_hw_breakpoint. */
4408 THREAD_STOPPED_BY (hw_breakpoint
)
4410 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4413 switch_to_thread_cleanup (void *ptid_p
)
4415 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4417 switch_to_thread (ptid
);
4420 /* Save the thread's event and stop reason to process it later. */
4423 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4425 struct regcache
*regcache
;
4426 struct address_space
*aspace
;
4432 statstr
= target_waitstatus_to_string (ws
);
4433 fprintf_unfiltered (gdb_stdlog
,
4434 "infrun: saving status %s for %d.%ld.%ld\n",
4436 ptid_get_pid (tp
->ptid
),
4437 ptid_get_lwp (tp
->ptid
),
4438 ptid_get_tid (tp
->ptid
));
4442 /* Record for later. */
4443 tp
->suspend
.waitstatus
= *ws
;
4444 tp
->suspend
.waitstatus_pending_p
= 1;
4446 regcache
= get_thread_regcache (tp
->ptid
);
4447 aspace
= get_regcache_aspace (regcache
);
4449 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4450 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4452 CORE_ADDR pc
= regcache_read_pc (regcache
);
4454 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4456 if (thread_stopped_by_watchpoint (tp
->ptid
))
4458 tp
->suspend
.stop_reason
4459 = TARGET_STOPPED_BY_WATCHPOINT
;
4461 else if (target_supports_stopped_by_sw_breakpoint ()
4462 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4464 tp
->suspend
.stop_reason
4465 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4467 else if (target_supports_stopped_by_hw_breakpoint ()
4468 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4470 tp
->suspend
.stop_reason
4471 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4473 else if (!target_supports_stopped_by_hw_breakpoint ()
4474 && hardware_breakpoint_inserted_here_p (aspace
,
4477 tp
->suspend
.stop_reason
4478 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4480 else if (!target_supports_stopped_by_sw_breakpoint ()
4481 && software_breakpoint_inserted_here_p (aspace
,
4484 tp
->suspend
.stop_reason
4485 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4487 else if (!thread_has_single_step_breakpoints_set (tp
)
4488 && currently_stepping (tp
))
4490 tp
->suspend
.stop_reason
4491 = TARGET_STOPPED_BY_SINGLE_STEP
;
4496 /* A cleanup that disables thread create/exit events. */
4499 disable_thread_events (void *arg
)
4501 target_thread_events (0);
4507 stop_all_threads (void)
4509 /* We may need multiple passes to discover all threads. */
4513 struct cleanup
*old_chain
;
4515 gdb_assert (target_is_non_stop_p ());
4518 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4520 entry_ptid
= inferior_ptid
;
4521 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4523 target_thread_events (1);
4524 make_cleanup (disable_thread_events
, NULL
);
4526 /* Request threads to stop, and then wait for the stops. Because
4527 threads we already know about can spawn more threads while we're
4528 trying to stop them, and we only learn about new threads when we
4529 update the thread list, do this in a loop, and keep iterating
4530 until two passes find no threads that need to be stopped. */
4531 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4534 fprintf_unfiltered (gdb_stdlog
,
4535 "infrun: stop_all_threads, pass=%d, "
4536 "iterations=%d\n", pass
, iterations
);
4540 struct target_waitstatus ws
;
4542 struct thread_info
*t
;
4544 update_thread_list ();
4546 /* Go through all threads looking for threads that we need
4547 to tell the target to stop. */
4548 ALL_NON_EXITED_THREADS (t
)
4552 /* If already stopping, don't request a stop again.
4553 We just haven't seen the notification yet. */
4554 if (!t
->stop_requested
)
4557 fprintf_unfiltered (gdb_stdlog
,
4558 "infrun: %s executing, "
4560 target_pid_to_str (t
->ptid
));
4561 target_stop (t
->ptid
);
4562 t
->stop_requested
= 1;
4567 fprintf_unfiltered (gdb_stdlog
,
4568 "infrun: %s executing, "
4569 "already stopping\n",
4570 target_pid_to_str (t
->ptid
));
4573 if (t
->stop_requested
)
4579 fprintf_unfiltered (gdb_stdlog
,
4580 "infrun: %s not executing\n",
4581 target_pid_to_str (t
->ptid
));
4583 /* The thread may be not executing, but still be
4584 resumed with a pending status to process. */
4592 /* If we find new threads on the second iteration, restart
4593 over. We want to see two iterations in a row with all
4598 event_ptid
= wait_one (&ws
);
4599 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4601 /* All resumed threads exited. */
4603 else if (ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4604 || ws
.kind
== TARGET_WAITKIND_EXITED
4605 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4609 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4611 fprintf_unfiltered (gdb_stdlog
,
4612 "infrun: %s exited while "
4613 "stopping threads\n",
4614 target_pid_to_str (ptid
));
4619 struct inferior
*inf
;
4621 t
= find_thread_ptid (event_ptid
);
4623 t
= add_thread (event_ptid
);
4625 t
->stop_requested
= 0;
4628 t
->control
.may_range_step
= 0;
4630 /* This may be the first time we see the inferior report
4632 inf
= find_inferior_ptid (event_ptid
);
4633 if (inf
->needs_setup
)
4635 switch_to_thread_no_regs (t
);
4639 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4640 && ws
.value
.sig
== GDB_SIGNAL_0
)
4642 /* We caught the event that we intended to catch, so
4643 there's no event pending. */
4644 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4645 t
->suspend
.waitstatus_pending_p
= 0;
4647 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4649 /* Add it back to the step-over queue. */
4652 fprintf_unfiltered (gdb_stdlog
,
4653 "infrun: displaced-step of %s "
4654 "canceled: adding back to the "
4655 "step-over queue\n",
4656 target_pid_to_str (t
->ptid
));
4658 t
->control
.trap_expected
= 0;
4659 thread_step_over_chain_enqueue (t
);
4664 enum gdb_signal sig
;
4665 struct regcache
*regcache
;
4671 statstr
= target_waitstatus_to_string (&ws
);
4672 fprintf_unfiltered (gdb_stdlog
,
4673 "infrun: target_wait %s, saving "
4674 "status for %d.%ld.%ld\n",
4676 ptid_get_pid (t
->ptid
),
4677 ptid_get_lwp (t
->ptid
),
4678 ptid_get_tid (t
->ptid
));
4682 /* Record for later. */
4683 save_waitstatus (t
, &ws
);
4685 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4686 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4688 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4690 /* Add it back to the step-over queue. */
4691 t
->control
.trap_expected
= 0;
4692 thread_step_over_chain_enqueue (t
);
4695 regcache
= get_thread_regcache (t
->ptid
);
4696 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4700 fprintf_unfiltered (gdb_stdlog
,
4701 "infrun: saved stop_pc=%s for %s "
4702 "(currently_stepping=%d)\n",
4703 paddress (target_gdbarch (),
4704 t
->suspend
.stop_pc
),
4705 target_pid_to_str (t
->ptid
),
4706 currently_stepping (t
));
4713 do_cleanups (old_chain
);
4716 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4719 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4722 handle_no_resumed (struct execution_control_state
*ecs
)
4724 struct inferior
*inf
;
4725 struct thread_info
*thread
;
4727 if (target_can_async_p ())
4734 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4742 /* There were no unwaited-for children left in the target, but,
4743 we're not synchronously waiting for events either. Just
4747 fprintf_unfiltered (gdb_stdlog
,
4748 "infrun: TARGET_WAITKIND_NO_RESUMED "
4749 "(ignoring: bg)\n");
4750 prepare_to_wait (ecs
);
4755 /* Otherwise, if we were running a synchronous execution command, we
4756 may need to cancel it and give the user back the terminal.
4758 In non-stop mode, the target can't tell whether we've already
4759 consumed previous stop events, so it can end up sending us a
4760 no-resumed event like so:
4762 #0 - thread 1 is left stopped
4764 #1 - thread 2 is resumed and hits breakpoint
4765 -> TARGET_WAITKIND_STOPPED
4767 #2 - thread 3 is resumed and exits
4768 this is the last resumed thread, so
4769 -> TARGET_WAITKIND_NO_RESUMED
4771 #3 - gdb processes stop for thread 2 and decides to re-resume
4774 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4775 thread 2 is now resumed, so the event should be ignored.
4777 IOW, if the stop for thread 2 doesn't end a foreground command,
4778 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4779 event. But it could be that the event meant that thread 2 itself
4780 (or whatever other thread was the last resumed thread) exited.
4782 To address this we refresh the thread list and check whether we
4783 have resumed threads _now_. In the example above, this removes
4784 thread 3 from the thread list. If thread 2 was re-resumed, we
4785 ignore this event. If we find no thread resumed, then we cancel
4786 the synchronous command show "no unwaited-for " to the user. */
4787 update_thread_list ();
4789 ALL_NON_EXITED_THREADS (thread
)
4791 if (thread
->executing
4792 || thread
->suspend
.waitstatus_pending_p
)
4794 /* There were no unwaited-for children left in the target at
4795 some point, but there are now. Just ignore. */
4797 fprintf_unfiltered (gdb_stdlog
,
4798 "infrun: TARGET_WAITKIND_NO_RESUMED "
4799 "(ignoring: found resumed)\n");
4800 prepare_to_wait (ecs
);
4805 /* Note however that we may find no resumed thread because the whole
4806 process exited meanwhile (thus updating the thread list results
4807 in an empty thread list). In this case we know we'll be getting
4808 a process exit event shortly. */
4814 thread
= any_live_thread_of_process (inf
->pid
);
4818 fprintf_unfiltered (gdb_stdlog
,
4819 "infrun: TARGET_WAITKIND_NO_RESUMED "
4820 "(expect process exit)\n");
4821 prepare_to_wait (ecs
);
4826 /* Go ahead and report the event. */
4830 /* Given an execution control state that has been freshly filled in by
4831 an event from the inferior, figure out what it means and take
4834 The alternatives are:
4836 1) stop_waiting and return; to really stop and return to the
4839 2) keep_going and return; to wait for the next event (set
4840 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4844 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4846 enum stop_kind stop_soon
;
4848 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4850 /* We had an event in the inferior, but we are not interested in
4851 handling it at this level. The lower layers have already
4852 done what needs to be done, if anything.
4854 One of the possible circumstances for this is when the
4855 inferior produces output for the console. The inferior has
4856 not stopped, and we are ignoring the event. Another possible
4857 circumstance is any event which the lower level knows will be
4858 reported multiple times without an intervening resume. */
4860 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4861 prepare_to_wait (ecs
);
4865 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4868 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4869 prepare_to_wait (ecs
);
4873 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4874 && handle_no_resumed (ecs
))
4877 /* Cache the last pid/waitstatus. */
4878 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4880 /* Always clear state belonging to the previous time we stopped. */
4881 stop_stack_dummy
= STOP_NONE
;
4883 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4885 /* No unwaited-for children left. IOW, all resumed children
4888 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4890 stop_print_frame
= 0;
4895 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4896 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4898 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4899 /* If it's a new thread, add it to the thread database. */
4900 if (ecs
->event_thread
== NULL
)
4901 ecs
->event_thread
= add_thread (ecs
->ptid
);
4903 /* Disable range stepping. If the next step request could use a
4904 range, this will be end up re-enabled then. */
4905 ecs
->event_thread
->control
.may_range_step
= 0;
4908 /* Dependent on valid ECS->EVENT_THREAD. */
4909 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4911 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4912 reinit_frame_cache ();
4914 breakpoint_retire_moribund ();
4916 /* First, distinguish signals caused by the debugger from signals
4917 that have to do with the program's own actions. Note that
4918 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4919 on the operating system version. Here we detect when a SIGILL or
4920 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4921 something similar for SIGSEGV, since a SIGSEGV will be generated
4922 when we're trying to execute a breakpoint instruction on a
4923 non-executable stack. This happens for call dummy breakpoints
4924 for architectures like SPARC that place call dummies on the
4926 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4927 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4928 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4929 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4931 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4933 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
4934 regcache_read_pc (regcache
)))
4937 fprintf_unfiltered (gdb_stdlog
,
4938 "infrun: Treating signal as SIGTRAP\n");
4939 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4943 /* Mark the non-executing threads accordingly. In all-stop, all
4944 threads of all processes are stopped when we get any event
4945 reported. In non-stop mode, only the event thread stops. */
4949 if (!target_is_non_stop_p ())
4950 mark_ptid
= minus_one_ptid
;
4951 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4952 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4954 /* If we're handling a process exit in non-stop mode, even
4955 though threads haven't been deleted yet, one would think
4956 that there is nothing to do, as threads of the dead process
4957 will be soon deleted, and threads of any other process were
4958 left running. However, on some targets, threads survive a
4959 process exit event. E.g., for the "checkpoint" command,
4960 when the current checkpoint/fork exits, linux-fork.c
4961 automatically switches to another fork from within
4962 target_mourn_inferior, by associating the same
4963 inferior/thread to another fork. We haven't mourned yet at
4964 this point, but we must mark any threads left in the
4965 process as not-executing so that finish_thread_state marks
4966 them stopped (in the user's perspective) if/when we present
4967 the stop to the user. */
4968 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4971 mark_ptid
= ecs
->ptid
;
4973 set_executing (mark_ptid
, 0);
4975 /* Likewise the resumed flag. */
4976 set_resumed (mark_ptid
, 0);
4979 switch (ecs
->ws
.kind
)
4981 case TARGET_WAITKIND_LOADED
:
4983 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4984 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4985 context_switch (ecs
->ptid
);
4986 /* Ignore gracefully during startup of the inferior, as it might
4987 be the shell which has just loaded some objects, otherwise
4988 add the symbols for the newly loaded objects. Also ignore at
4989 the beginning of an attach or remote session; we will query
4990 the full list of libraries once the connection is
4993 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4994 if (stop_soon
== NO_STOP_QUIETLY
)
4996 struct regcache
*regcache
;
4998 regcache
= get_thread_regcache (ecs
->ptid
);
5000 handle_solib_event ();
5002 ecs
->event_thread
->control
.stop_bpstat
5003 = bpstat_stop_status (get_regcache_aspace (regcache
),
5004 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5006 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5008 /* A catchpoint triggered. */
5009 process_event_stop_test (ecs
);
5013 /* If requested, stop when the dynamic linker notifies
5014 gdb of events. This allows the user to get control
5015 and place breakpoints in initializer routines for
5016 dynamically loaded objects (among other things). */
5017 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5018 if (stop_on_solib_events
)
5020 /* Make sure we print "Stopped due to solib-event" in
5022 stop_print_frame
= 1;
5029 /* If we are skipping through a shell, or through shared library
5030 loading that we aren't interested in, resume the program. If
5031 we're running the program normally, also resume. */
5032 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5034 /* Loading of shared libraries might have changed breakpoint
5035 addresses. Make sure new breakpoints are inserted. */
5036 if (stop_soon
== NO_STOP_QUIETLY
)
5037 insert_breakpoints ();
5038 resume (GDB_SIGNAL_0
);
5039 prepare_to_wait (ecs
);
5043 /* But stop if we're attaching or setting up a remote
5045 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5046 || stop_soon
== STOP_QUIETLY_REMOTE
)
5049 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5054 internal_error (__FILE__
, __LINE__
,
5055 _("unhandled stop_soon: %d"), (int) stop_soon
);
5057 case TARGET_WAITKIND_SPURIOUS
:
5059 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
5060 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5061 context_switch (ecs
->ptid
);
5062 resume (GDB_SIGNAL_0
);
5063 prepare_to_wait (ecs
);
5066 case TARGET_WAITKIND_THREAD_CREATED
:
5068 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
5069 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5070 context_switch (ecs
->ptid
);
5071 if (!switch_back_to_stepped_thread (ecs
))
5075 case TARGET_WAITKIND_EXITED
:
5076 case TARGET_WAITKIND_SIGNALLED
:
5079 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5080 fprintf_unfiltered (gdb_stdlog
,
5081 "infrun: TARGET_WAITKIND_EXITED\n");
5083 fprintf_unfiltered (gdb_stdlog
,
5084 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5087 inferior_ptid
= ecs
->ptid
;
5088 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
5089 set_current_program_space (current_inferior ()->pspace
);
5090 handle_vfork_child_exec_or_exit (0);
5091 target_terminal_ours (); /* Must do this before mourn anyway. */
5093 /* Clearing any previous state of convenience variables. */
5094 clear_exit_convenience_vars ();
5096 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5098 /* Record the exit code in the convenience variable $_exitcode, so
5099 that the user can inspect this again later. */
5100 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5101 (LONGEST
) ecs
->ws
.value
.integer
);
5103 /* Also record this in the inferior itself. */
5104 current_inferior ()->has_exit_code
= 1;
5105 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5107 /* Support the --return-child-result option. */
5108 return_child_result_value
= ecs
->ws
.value
.integer
;
5110 observer_notify_exited (ecs
->ws
.value
.integer
);
5114 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5115 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5117 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5119 /* Set the value of the internal variable $_exitsignal,
5120 which holds the signal uncaught by the inferior. */
5121 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5122 gdbarch_gdb_signal_to_target (gdbarch
,
5123 ecs
->ws
.value
.sig
));
5127 /* We don't have access to the target's method used for
5128 converting between signal numbers (GDB's internal
5129 representation <-> target's representation).
5130 Therefore, we cannot do a good job at displaying this
5131 information to the user. It's better to just warn
5132 her about it (if infrun debugging is enabled), and
5135 fprintf_filtered (gdb_stdlog
, _("\
5136 Cannot fill $_exitsignal with the correct signal number.\n"));
5139 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
5142 gdb_flush (gdb_stdout
);
5143 target_mourn_inferior ();
5144 stop_print_frame
= 0;
5148 /* The following are the only cases in which we keep going;
5149 the above cases end in a continue or goto. */
5150 case TARGET_WAITKIND_FORKED
:
5151 case TARGET_WAITKIND_VFORKED
:
5154 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5155 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
5157 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
5160 /* Check whether the inferior is displaced stepping. */
5162 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5163 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5165 /* If checking displaced stepping is supported, and thread
5166 ecs->ptid is displaced stepping. */
5167 if (displaced_step_in_progress_thread (ecs
->ptid
))
5169 struct inferior
*parent_inf
5170 = find_inferior_ptid (ecs
->ptid
);
5171 struct regcache
*child_regcache
;
5172 CORE_ADDR parent_pc
;
5174 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5175 indicating that the displaced stepping of syscall instruction
5176 has been done. Perform cleanup for parent process here. Note
5177 that this operation also cleans up the child process for vfork,
5178 because their pages are shared. */
5179 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
5180 /* Start a new step-over in another thread if there's one
5184 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5186 struct displaced_step_inferior_state
*displaced
5187 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
5189 /* Restore scratch pad for child process. */
5190 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
5193 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5194 the child's PC is also within the scratchpad. Set the child's PC
5195 to the parent's PC value, which has already been fixed up.
5196 FIXME: we use the parent's aspace here, although we're touching
5197 the child, because the child hasn't been added to the inferior
5198 list yet at this point. */
5201 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
5203 parent_inf
->aspace
);
5204 /* Read PC value of parent process. */
5205 parent_pc
= regcache_read_pc (regcache
);
5207 if (debug_displaced
)
5208 fprintf_unfiltered (gdb_stdlog
,
5209 "displaced: write child pc from %s to %s\n",
5211 regcache_read_pc (child_regcache
)),
5212 paddress (gdbarch
, parent_pc
));
5214 regcache_write_pc (child_regcache
, parent_pc
);
5218 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5219 context_switch (ecs
->ptid
);
5221 /* Immediately detach breakpoints from the child before there's
5222 any chance of letting the user delete breakpoints from the
5223 breakpoint lists. If we don't do this early, it's easy to
5224 leave left over traps in the child, vis: "break foo; catch
5225 fork; c; <fork>; del; c; <child calls foo>". We only follow
5226 the fork on the last `continue', and by that time the
5227 breakpoint at "foo" is long gone from the breakpoint table.
5228 If we vforked, then we don't need to unpatch here, since both
5229 parent and child are sharing the same memory pages; we'll
5230 need to unpatch at follow/detach time instead to be certain
5231 that new breakpoints added between catchpoint hit time and
5232 vfork follow are detached. */
5233 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5235 /* This won't actually modify the breakpoint list, but will
5236 physically remove the breakpoints from the child. */
5237 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5240 delete_just_stopped_threads_single_step_breakpoints ();
5242 /* In case the event is caught by a catchpoint, remember that
5243 the event is to be followed at the next resume of the thread,
5244 and not immediately. */
5245 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5247 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5249 ecs
->event_thread
->control
.stop_bpstat
5250 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5251 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5253 /* If no catchpoint triggered for this, then keep going. Note
5254 that we're interested in knowing the bpstat actually causes a
5255 stop, not just if it may explain the signal. Software
5256 watchpoints, for example, always appear in the bpstat. */
5257 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5263 = (follow_fork_mode_string
== follow_fork_mode_child
);
5265 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5267 should_resume
= follow_fork ();
5270 child
= ecs
->ws
.value
.related_pid
;
5272 /* At this point, the parent is marked running, and the
5273 child is marked stopped. */
5275 /* If not resuming the parent, mark it stopped. */
5276 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5277 set_running (parent
, 0);
5279 /* If resuming the child, mark it running. */
5280 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5281 set_running (child
, 1);
5283 /* In non-stop mode, also resume the other branch. */
5284 if (!detach_fork
&& (non_stop
5285 || (sched_multi
&& target_is_non_stop_p ())))
5288 switch_to_thread (parent
);
5290 switch_to_thread (child
);
5292 ecs
->event_thread
= inferior_thread ();
5293 ecs
->ptid
= inferior_ptid
;
5298 switch_to_thread (child
);
5300 switch_to_thread (parent
);
5302 ecs
->event_thread
= inferior_thread ();
5303 ecs
->ptid
= inferior_ptid
;
5311 process_event_stop_test (ecs
);
5314 case TARGET_WAITKIND_VFORK_DONE
:
5315 /* Done with the shared memory region. Re-insert breakpoints in
5316 the parent, and keep going. */
5319 fprintf_unfiltered (gdb_stdlog
,
5320 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5322 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5323 context_switch (ecs
->ptid
);
5325 current_inferior ()->waiting_for_vfork_done
= 0;
5326 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5327 /* This also takes care of reinserting breakpoints in the
5328 previously locked inferior. */
5332 case TARGET_WAITKIND_EXECD
:
5334 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5336 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5337 context_switch (ecs
->ptid
);
5339 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5341 /* Do whatever is necessary to the parent branch of the vfork. */
5342 handle_vfork_child_exec_or_exit (1);
5344 /* This causes the eventpoints and symbol table to be reset.
5345 Must do this now, before trying to determine whether to
5347 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5349 /* In follow_exec we may have deleted the original thread and
5350 created a new one. Make sure that the event thread is the
5351 execd thread for that case (this is a nop otherwise). */
5352 ecs
->event_thread
= inferior_thread ();
5354 ecs
->event_thread
->control
.stop_bpstat
5355 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5356 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5358 /* Note that this may be referenced from inside
5359 bpstat_stop_status above, through inferior_has_execd. */
5360 xfree (ecs
->ws
.value
.execd_pathname
);
5361 ecs
->ws
.value
.execd_pathname
= NULL
;
5363 /* If no catchpoint triggered for this, then keep going. */
5364 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5366 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5370 process_event_stop_test (ecs
);
5373 /* Be careful not to try to gather much state about a thread
5374 that's in a syscall. It's frequently a losing proposition. */
5375 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5377 fprintf_unfiltered (gdb_stdlog
,
5378 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5379 /* Getting the current syscall number. */
5380 if (handle_syscall_event (ecs
) == 0)
5381 process_event_stop_test (ecs
);
5384 /* Before examining the threads further, step this thread to
5385 get it entirely out of the syscall. (We get notice of the
5386 event when the thread is just on the verge of exiting a
5387 syscall. Stepping one instruction seems to get it back
5389 case TARGET_WAITKIND_SYSCALL_RETURN
:
5391 fprintf_unfiltered (gdb_stdlog
,
5392 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5393 if (handle_syscall_event (ecs
) == 0)
5394 process_event_stop_test (ecs
);
5397 case TARGET_WAITKIND_STOPPED
:
5399 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5400 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5401 handle_signal_stop (ecs
);
5404 case TARGET_WAITKIND_NO_HISTORY
:
5406 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5407 /* Reverse execution: target ran out of history info. */
5409 /* Switch to the stopped thread. */
5410 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5411 context_switch (ecs
->ptid
);
5413 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5415 delete_just_stopped_threads_single_step_breakpoints ();
5416 stop_pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
5417 observer_notify_no_history ();
5423 /* A wrapper around handle_inferior_event_1, which also makes sure
5424 that all temporary struct value objects that were created during
5425 the handling of the event get deleted at the end. */
5428 handle_inferior_event (struct execution_control_state
*ecs
)
5430 struct value
*mark
= value_mark ();
5432 handle_inferior_event_1 (ecs
);
5433 /* Purge all temporary values created during the event handling,
5434 as it could be a long time before we return to the command level
5435 where such values would otherwise be purged. */
5436 value_free_to_mark (mark
);
5439 /* Restart threads back to what they were trying to do back when we
5440 paused them for an in-line step-over. The EVENT_THREAD thread is
5444 restart_threads (struct thread_info
*event_thread
)
5446 struct thread_info
*tp
;
5448 /* In case the instruction just stepped spawned a new thread. */
5449 update_thread_list ();
5451 ALL_NON_EXITED_THREADS (tp
)
5453 if (tp
== event_thread
)
5456 fprintf_unfiltered (gdb_stdlog
,
5457 "infrun: restart threads: "
5458 "[%s] is event thread\n",
5459 target_pid_to_str (tp
->ptid
));
5463 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5466 fprintf_unfiltered (gdb_stdlog
,
5467 "infrun: restart threads: "
5468 "[%s] not meant to be running\n",
5469 target_pid_to_str (tp
->ptid
));
5476 fprintf_unfiltered (gdb_stdlog
,
5477 "infrun: restart threads: [%s] resumed\n",
5478 target_pid_to_str (tp
->ptid
));
5479 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5483 if (thread_is_in_step_over_chain (tp
))
5486 fprintf_unfiltered (gdb_stdlog
,
5487 "infrun: restart threads: "
5488 "[%s] needs step-over\n",
5489 target_pid_to_str (tp
->ptid
));
5490 gdb_assert (!tp
->resumed
);
5495 if (tp
->suspend
.waitstatus_pending_p
)
5498 fprintf_unfiltered (gdb_stdlog
,
5499 "infrun: restart threads: "
5500 "[%s] has pending status\n",
5501 target_pid_to_str (tp
->ptid
));
5506 /* If some thread needs to start a step-over at this point, it
5507 should still be in the step-over queue, and thus skipped
5509 if (thread_still_needs_step_over (tp
))
5511 internal_error (__FILE__
, __LINE__
,
5512 "thread [%s] needs a step-over, but not in "
5513 "step-over queue\n",
5514 target_pid_to_str (tp
->ptid
));
5517 if (currently_stepping (tp
))
5520 fprintf_unfiltered (gdb_stdlog
,
5521 "infrun: restart threads: [%s] was stepping\n",
5522 target_pid_to_str (tp
->ptid
));
5523 keep_going_stepped_thread (tp
);
5527 struct execution_control_state ecss
;
5528 struct execution_control_state
*ecs
= &ecss
;
5531 fprintf_unfiltered (gdb_stdlog
,
5532 "infrun: restart threads: [%s] continuing\n",
5533 target_pid_to_str (tp
->ptid
));
5534 reset_ecs (ecs
, tp
);
5535 switch_to_thread (tp
->ptid
);
5536 keep_going_pass_signal (ecs
);
5541 /* Callback for iterate_over_threads. Find a resumed thread that has
5542 a pending waitstatus. */
5545 resumed_thread_with_pending_status (struct thread_info
*tp
,
5549 && tp
->suspend
.waitstatus_pending_p
);
5552 /* Called when we get an event that may finish an in-line or
5553 out-of-line (displaced stepping) step-over started previously.
5554 Return true if the event is processed and we should go back to the
5555 event loop; false if the caller should continue processing the
5559 finish_step_over (struct execution_control_state
*ecs
)
5561 int had_step_over_info
;
5563 displaced_step_fixup (ecs
->ptid
,
5564 ecs
->event_thread
->suspend
.stop_signal
);
5566 had_step_over_info
= step_over_info_valid_p ();
5568 if (had_step_over_info
)
5570 /* If we're stepping over a breakpoint with all threads locked,
5571 then only the thread that was stepped should be reporting
5573 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5575 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5576 clear_step_over_info ();
5579 if (!target_is_non_stop_p ())
5582 /* Start a new step-over in another thread if there's one that
5586 /* If we were stepping over a breakpoint before, and haven't started
5587 a new in-line step-over sequence, then restart all other threads
5588 (except the event thread). We can't do this in all-stop, as then
5589 e.g., we wouldn't be able to issue any other remote packet until
5590 these other threads stop. */
5591 if (had_step_over_info
&& !step_over_info_valid_p ())
5593 struct thread_info
*pending
;
5595 /* If we only have threads with pending statuses, the restart
5596 below won't restart any thread and so nothing re-inserts the
5597 breakpoint we just stepped over. But we need it inserted
5598 when we later process the pending events, otherwise if
5599 another thread has a pending event for this breakpoint too,
5600 we'd discard its event (because the breakpoint that
5601 originally caused the event was no longer inserted). */
5602 context_switch (ecs
->ptid
);
5603 insert_breakpoints ();
5605 restart_threads (ecs
->event_thread
);
5607 /* If we have events pending, go through handle_inferior_event
5608 again, picking up a pending event at random. This avoids
5609 thread starvation. */
5611 /* But not if we just stepped over a watchpoint in order to let
5612 the instruction execute so we can evaluate its expression.
5613 The set of watchpoints that triggered is recorded in the
5614 breakpoint objects themselves (see bp->watchpoint_triggered).
5615 If we processed another event first, that other event could
5616 clobber this info. */
5617 if (ecs
->event_thread
->stepping_over_watchpoint
)
5620 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5622 if (pending
!= NULL
)
5624 struct thread_info
*tp
= ecs
->event_thread
;
5625 struct regcache
*regcache
;
5629 fprintf_unfiltered (gdb_stdlog
,
5630 "infrun: found resumed threads with "
5631 "pending events, saving status\n");
5634 gdb_assert (pending
!= tp
);
5636 /* Record the event thread's event for later. */
5637 save_waitstatus (tp
, &ecs
->ws
);
5638 /* This was cleared early, by handle_inferior_event. Set it
5639 so this pending event is considered by
5643 gdb_assert (!tp
->executing
);
5645 regcache
= get_thread_regcache (tp
->ptid
);
5646 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5650 fprintf_unfiltered (gdb_stdlog
,
5651 "infrun: saved stop_pc=%s for %s "
5652 "(currently_stepping=%d)\n",
5653 paddress (target_gdbarch (),
5654 tp
->suspend
.stop_pc
),
5655 target_pid_to_str (tp
->ptid
),
5656 currently_stepping (tp
));
5659 /* This in-line step-over finished; clear this so we won't
5660 start a new one. This is what handle_signal_stop would
5661 do, if we returned false. */
5662 tp
->stepping_over_breakpoint
= 0;
5664 /* Wake up the event loop again. */
5665 mark_async_event_handler (infrun_async_inferior_event_token
);
5667 prepare_to_wait (ecs
);
5675 /* Come here when the program has stopped with a signal. */
5678 handle_signal_stop (struct execution_control_state
*ecs
)
5680 struct frame_info
*frame
;
5681 struct gdbarch
*gdbarch
;
5682 int stopped_by_watchpoint
;
5683 enum stop_kind stop_soon
;
5686 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5688 /* Do we need to clean up the state of a thread that has
5689 completed a displaced single-step? (Doing so usually affects
5690 the PC, so do it here, before we set stop_pc.) */
5691 if (finish_step_over (ecs
))
5694 /* If we either finished a single-step or hit a breakpoint, but
5695 the user wanted this thread to be stopped, pretend we got a
5696 SIG0 (generic unsignaled stop). */
5697 if (ecs
->event_thread
->stop_requested
5698 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5699 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5701 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5705 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5706 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
5707 struct cleanup
*old_chain
= save_inferior_ptid ();
5709 inferior_ptid
= ecs
->ptid
;
5711 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5712 paddress (gdbarch
, stop_pc
));
5713 if (target_stopped_by_watchpoint ())
5717 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5719 if (target_stopped_data_address (¤t_target
, &addr
))
5720 fprintf_unfiltered (gdb_stdlog
,
5721 "infrun: stopped data address = %s\n",
5722 paddress (gdbarch
, addr
));
5724 fprintf_unfiltered (gdb_stdlog
,
5725 "infrun: (no data address available)\n");
5728 do_cleanups (old_chain
);
5731 /* This is originated from start_remote(), start_inferior() and
5732 shared libraries hook functions. */
5733 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5734 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5736 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5737 context_switch (ecs
->ptid
);
5739 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5740 stop_print_frame
= 1;
5745 /* This originates from attach_command(). We need to overwrite
5746 the stop_signal here, because some kernels don't ignore a
5747 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5748 See more comments in inferior.h. On the other hand, if we
5749 get a non-SIGSTOP, report it to the user - assume the backend
5750 will handle the SIGSTOP if it should show up later.
5752 Also consider that the attach is complete when we see a
5753 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5754 target extended-remote report it instead of a SIGSTOP
5755 (e.g. gdbserver). We already rely on SIGTRAP being our
5756 signal, so this is no exception.
5758 Also consider that the attach is complete when we see a
5759 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5760 the target to stop all threads of the inferior, in case the
5761 low level attach operation doesn't stop them implicitly. If
5762 they weren't stopped implicitly, then the stub will report a
5763 GDB_SIGNAL_0, meaning: stopped for no particular reason
5764 other than GDB's request. */
5765 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5766 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5767 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5768 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5770 stop_print_frame
= 1;
5772 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5776 /* See if something interesting happened to the non-current thread. If
5777 so, then switch to that thread. */
5778 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5781 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5783 context_switch (ecs
->ptid
);
5785 if (deprecated_context_hook
)
5786 deprecated_context_hook (ptid_to_global_thread_id (ecs
->ptid
));
5789 /* At this point, get hold of the now-current thread's frame. */
5790 frame
= get_current_frame ();
5791 gdbarch
= get_frame_arch (frame
);
5793 /* Pull the single step breakpoints out of the target. */
5794 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5796 struct regcache
*regcache
;
5797 struct address_space
*aspace
;
5800 regcache
= get_thread_regcache (ecs
->ptid
);
5801 aspace
= get_regcache_aspace (regcache
);
5802 pc
= regcache_read_pc (regcache
);
5804 /* However, before doing so, if this single-step breakpoint was
5805 actually for another thread, set this thread up for moving
5807 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5810 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5814 fprintf_unfiltered (gdb_stdlog
,
5815 "infrun: [%s] hit another thread's "
5816 "single-step breakpoint\n",
5817 target_pid_to_str (ecs
->ptid
));
5819 ecs
->hit_singlestep_breakpoint
= 1;
5826 fprintf_unfiltered (gdb_stdlog
,
5827 "infrun: [%s] hit its "
5828 "single-step breakpoint\n",
5829 target_pid_to_str (ecs
->ptid
));
5833 delete_just_stopped_threads_single_step_breakpoints ();
5835 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5836 && ecs
->event_thread
->control
.trap_expected
5837 && ecs
->event_thread
->stepping_over_watchpoint
)
5838 stopped_by_watchpoint
= 0;
5840 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5842 /* If necessary, step over this watchpoint. We'll be back to display
5844 if (stopped_by_watchpoint
5845 && (target_have_steppable_watchpoint
5846 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5848 /* At this point, we are stopped at an instruction which has
5849 attempted to write to a piece of memory under control of
5850 a watchpoint. The instruction hasn't actually executed
5851 yet. If we were to evaluate the watchpoint expression
5852 now, we would get the old value, and therefore no change
5853 would seem to have occurred.
5855 In order to make watchpoints work `right', we really need
5856 to complete the memory write, and then evaluate the
5857 watchpoint expression. We do this by single-stepping the
5860 It may not be necessary to disable the watchpoint to step over
5861 it. For example, the PA can (with some kernel cooperation)
5862 single step over a watchpoint without disabling the watchpoint.
5864 It is far more common to need to disable a watchpoint to step
5865 the inferior over it. If we have non-steppable watchpoints,
5866 we must disable the current watchpoint; it's simplest to
5867 disable all watchpoints.
5869 Any breakpoint at PC must also be stepped over -- if there's
5870 one, it will have already triggered before the watchpoint
5871 triggered, and we either already reported it to the user, or
5872 it didn't cause a stop and we called keep_going. In either
5873 case, if there was a breakpoint at PC, we must be trying to
5875 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5880 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5881 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5882 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5883 ecs
->event_thread
->control
.stop_step
= 0;
5884 stop_print_frame
= 1;
5885 stopped_by_random_signal
= 0;
5887 /* Hide inlined functions starting here, unless we just performed stepi or
5888 nexti. After stepi and nexti, always show the innermost frame (not any
5889 inline function call sites). */
5890 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5892 struct address_space
*aspace
=
5893 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
5895 /* skip_inline_frames is expensive, so we avoid it if we can
5896 determine that the address is one where functions cannot have
5897 been inlined. This improves performance with inferiors that
5898 load a lot of shared libraries, because the solib event
5899 breakpoint is defined as the address of a function (i.e. not
5900 inline). Note that we have to check the previous PC as well
5901 as the current one to catch cases when we have just
5902 single-stepped off a breakpoint prior to reinstating it.
5903 Note that we're assuming that the code we single-step to is
5904 not inline, but that's not definitive: there's nothing
5905 preventing the event breakpoint function from containing
5906 inlined code, and the single-step ending up there. If the
5907 user had set a breakpoint on that inlined code, the missing
5908 skip_inline_frames call would break things. Fortunately
5909 that's an extremely unlikely scenario. */
5910 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5911 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5912 && ecs
->event_thread
->control
.trap_expected
5913 && pc_at_non_inline_function (aspace
,
5914 ecs
->event_thread
->prev_pc
,
5917 skip_inline_frames (ecs
->ptid
);
5919 /* Re-fetch current thread's frame in case that invalidated
5921 frame
= get_current_frame ();
5922 gdbarch
= get_frame_arch (frame
);
5926 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5927 && ecs
->event_thread
->control
.trap_expected
5928 && gdbarch_single_step_through_delay_p (gdbarch
)
5929 && currently_stepping (ecs
->event_thread
))
5931 /* We're trying to step off a breakpoint. Turns out that we're
5932 also on an instruction that needs to be stepped multiple
5933 times before it's been fully executing. E.g., architectures
5934 with a delay slot. It needs to be stepped twice, once for
5935 the instruction and once for the delay slot. */
5936 int step_through_delay
5937 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5939 if (debug_infrun
&& step_through_delay
)
5940 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5941 if (ecs
->event_thread
->control
.step_range_end
== 0
5942 && step_through_delay
)
5944 /* The user issued a continue when stopped at a breakpoint.
5945 Set up for another trap and get out of here. */
5946 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5950 else if (step_through_delay
)
5952 /* The user issued a step when stopped at a breakpoint.
5953 Maybe we should stop, maybe we should not - the delay
5954 slot *might* correspond to a line of source. In any
5955 case, don't decide that here, just set
5956 ecs->stepping_over_breakpoint, making sure we
5957 single-step again before breakpoints are re-inserted. */
5958 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5962 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5963 handles this event. */
5964 ecs
->event_thread
->control
.stop_bpstat
5965 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
5966 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5968 /* Following in case break condition called a
5970 stop_print_frame
= 1;
5972 /* This is where we handle "moribund" watchpoints. Unlike
5973 software breakpoints traps, hardware watchpoint traps are
5974 always distinguishable from random traps. If no high-level
5975 watchpoint is associated with the reported stop data address
5976 anymore, then the bpstat does not explain the signal ---
5977 simply make sure to ignore it if `stopped_by_watchpoint' is
5981 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5982 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5984 && stopped_by_watchpoint
)
5985 fprintf_unfiltered (gdb_stdlog
,
5986 "infrun: no user watchpoint explains "
5987 "watchpoint SIGTRAP, ignoring\n");
5989 /* NOTE: cagney/2003-03-29: These checks for a random signal
5990 at one stage in the past included checks for an inferior
5991 function call's call dummy's return breakpoint. The original
5992 comment, that went with the test, read:
5994 ``End of a stack dummy. Some systems (e.g. Sony news) give
5995 another signal besides SIGTRAP, so check here as well as
5998 If someone ever tries to get call dummys on a
5999 non-executable stack to work (where the target would stop
6000 with something like a SIGSEGV), then those tests might need
6001 to be re-instated. Given, however, that the tests were only
6002 enabled when momentary breakpoints were not being used, I
6003 suspect that it won't be the case.
6005 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
6006 be necessary for call dummies on a non-executable stack on
6009 /* See if the breakpoints module can explain the signal. */
6011 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6012 ecs
->event_thread
->suspend
.stop_signal
);
6014 /* Maybe this was a trap for a software breakpoint that has since
6016 if (random_signal
&& target_stopped_by_sw_breakpoint ())
6018 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
6020 struct regcache
*regcache
;
6023 /* Re-adjust PC to what the program would see if GDB was not
6025 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
6026 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6029 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
6031 if (record_full_is_used ())
6032 record_full_gdb_operation_disable_set ();
6034 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
6036 do_cleanups (old_cleanups
);
6041 /* A delayed software breakpoint event. Ignore the trap. */
6043 fprintf_unfiltered (gdb_stdlog
,
6044 "infrun: delayed software breakpoint "
6045 "trap, ignoring\n");
6050 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6051 has since been removed. */
6052 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6054 /* A delayed hardware breakpoint event. Ignore the trap. */
6056 fprintf_unfiltered (gdb_stdlog
,
6057 "infrun: delayed hardware breakpoint/watchpoint "
6058 "trap, ignoring\n");
6062 /* If not, perhaps stepping/nexting can. */
6064 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6065 && currently_stepping (ecs
->event_thread
));
6067 /* Perhaps the thread hit a single-step breakpoint of _another_
6068 thread. Single-step breakpoints are transparent to the
6069 breakpoints module. */
6071 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6073 /* No? Perhaps we got a moribund watchpoint. */
6075 random_signal
= !stopped_by_watchpoint
;
6077 /* For the program's own signals, act according to
6078 the signal handling tables. */
6082 /* Signal not for debugging purposes. */
6083 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
6084 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6087 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
6088 gdb_signal_to_symbol_string (stop_signal
));
6090 stopped_by_random_signal
= 1;
6092 /* Always stop on signals if we're either just gaining control
6093 of the program, or the user explicitly requested this thread
6094 to remain stopped. */
6095 if (stop_soon
!= NO_STOP_QUIETLY
6096 || ecs
->event_thread
->stop_requested
6098 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
6104 /* Notify observers the signal has "handle print" set. Note we
6105 returned early above if stopping; normal_stop handles the
6106 printing in that case. */
6107 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6109 /* The signal table tells us to print about this signal. */
6110 target_terminal_ours_for_output ();
6111 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
6112 target_terminal_inferior ();
6115 /* Clear the signal if it should not be passed. */
6116 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6117 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6119 if (ecs
->event_thread
->prev_pc
== stop_pc
6120 && ecs
->event_thread
->control
.trap_expected
6121 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6125 /* We were just starting a new sequence, attempting to
6126 single-step off of a breakpoint and expecting a SIGTRAP.
6127 Instead this signal arrives. This signal will take us out
6128 of the stepping range so GDB needs to remember to, when
6129 the signal handler returns, resume stepping off that
6131 /* To simplify things, "continue" is forced to use the same
6132 code paths as single-step - set a breakpoint at the
6133 signal return address and then, once hit, step off that
6136 fprintf_unfiltered (gdb_stdlog
,
6137 "infrun: signal arrived while stepping over "
6140 was_in_line
= step_over_info_valid_p ();
6141 clear_step_over_info ();
6142 insert_hp_step_resume_breakpoint_at_frame (frame
);
6143 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6144 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6145 ecs
->event_thread
->control
.trap_expected
= 0;
6147 if (target_is_non_stop_p ())
6149 /* Either "set non-stop" is "on", or the target is
6150 always in non-stop mode. In this case, we have a bit
6151 more work to do. Resume the current thread, and if
6152 we had paused all threads, restart them while the
6153 signal handler runs. */
6158 restart_threads (ecs
->event_thread
);
6160 else if (debug_infrun
)
6162 fprintf_unfiltered (gdb_stdlog
,
6163 "infrun: no need to restart threads\n");
6168 /* If we were nexting/stepping some other thread, switch to
6169 it, so that we don't continue it, losing control. */
6170 if (!switch_back_to_stepped_thread (ecs
))
6175 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6176 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6177 || ecs
->event_thread
->control
.step_range_end
== 1)
6178 && frame_id_eq (get_stack_frame_id (frame
),
6179 ecs
->event_thread
->control
.step_stack_frame_id
)
6180 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6182 /* The inferior is about to take a signal that will take it
6183 out of the single step range. Set a breakpoint at the
6184 current PC (which is presumably where the signal handler
6185 will eventually return) and then allow the inferior to
6188 Note that this is only needed for a signal delivered
6189 while in the single-step range. Nested signals aren't a
6190 problem as they eventually all return. */
6192 fprintf_unfiltered (gdb_stdlog
,
6193 "infrun: signal may take us out of "
6194 "single-step range\n");
6196 clear_step_over_info ();
6197 insert_hp_step_resume_breakpoint_at_frame (frame
);
6198 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6199 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6200 ecs
->event_thread
->control
.trap_expected
= 0;
6205 /* Note: step_resume_breakpoint may be non-NULL. This occures
6206 when either there's a nested signal, or when there's a
6207 pending signal enabled just as the signal handler returns
6208 (leaving the inferior at the step-resume-breakpoint without
6209 actually executing it). Either way continue until the
6210 breakpoint is really hit. */
6212 if (!switch_back_to_stepped_thread (ecs
))
6215 fprintf_unfiltered (gdb_stdlog
,
6216 "infrun: random signal, keep going\n");
6223 process_event_stop_test (ecs
);
6226 /* Come here when we've got some debug event / signal we can explain
6227 (IOW, not a random signal), and test whether it should cause a
6228 stop, or whether we should resume the inferior (transparently).
6229 E.g., could be a breakpoint whose condition evaluates false; we
6230 could be still stepping within the line; etc. */
6233 process_event_stop_test (struct execution_control_state
*ecs
)
6235 struct symtab_and_line stop_pc_sal
;
6236 struct frame_info
*frame
;
6237 struct gdbarch
*gdbarch
;
6238 CORE_ADDR jmp_buf_pc
;
6239 struct bpstat_what what
;
6241 /* Handle cases caused by hitting a breakpoint. */
6243 frame
= get_current_frame ();
6244 gdbarch
= get_frame_arch (frame
);
6246 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6248 if (what
.call_dummy
)
6250 stop_stack_dummy
= what
.call_dummy
;
6253 /* A few breakpoint types have callbacks associated (e.g.,
6254 bp_jit_event). Run them now. */
6255 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6257 /* If we hit an internal event that triggers symbol changes, the
6258 current frame will be invalidated within bpstat_what (e.g., if we
6259 hit an internal solib event). Re-fetch it. */
6260 frame
= get_current_frame ();
6261 gdbarch
= get_frame_arch (frame
);
6263 switch (what
.main_action
)
6265 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6266 /* If we hit the breakpoint at longjmp while stepping, we
6267 install a momentary breakpoint at the target of the
6271 fprintf_unfiltered (gdb_stdlog
,
6272 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6274 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6276 if (what
.is_longjmp
)
6278 struct value
*arg_value
;
6280 /* If we set the longjmp breakpoint via a SystemTap probe,
6281 then use it to extract the arguments. The destination PC
6282 is the third argument to the probe. */
6283 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6286 jmp_buf_pc
= value_as_address (arg_value
);
6287 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6289 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6290 || !gdbarch_get_longjmp_target (gdbarch
,
6291 frame
, &jmp_buf_pc
))
6294 fprintf_unfiltered (gdb_stdlog
,
6295 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6296 "(!gdbarch_get_longjmp_target)\n");
6301 /* Insert a breakpoint at resume address. */
6302 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6305 check_exception_resume (ecs
, frame
);
6309 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6311 struct frame_info
*init_frame
;
6313 /* There are several cases to consider.
6315 1. The initiating frame no longer exists. In this case we
6316 must stop, because the exception or longjmp has gone too
6319 2. The initiating frame exists, and is the same as the
6320 current frame. We stop, because the exception or longjmp
6323 3. The initiating frame exists and is different from the
6324 current frame. This means the exception or longjmp has
6325 been caught beneath the initiating frame, so keep going.
6327 4. longjmp breakpoint has been placed just to protect
6328 against stale dummy frames and user is not interested in
6329 stopping around longjmps. */
6332 fprintf_unfiltered (gdb_stdlog
,
6333 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6335 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6337 delete_exception_resume_breakpoint (ecs
->event_thread
);
6339 if (what
.is_longjmp
)
6341 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6343 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6351 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6355 struct frame_id current_id
6356 = get_frame_id (get_current_frame ());
6357 if (frame_id_eq (current_id
,
6358 ecs
->event_thread
->initiating_frame
))
6360 /* Case 2. Fall through. */
6370 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6372 delete_step_resume_breakpoint (ecs
->event_thread
);
6374 end_stepping_range (ecs
);
6378 case BPSTAT_WHAT_SINGLE
:
6380 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6381 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6382 /* Still need to check other stuff, at least the case where we
6383 are stepping and step out of the right range. */
6386 case BPSTAT_WHAT_STEP_RESUME
:
6388 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6390 delete_step_resume_breakpoint (ecs
->event_thread
);
6391 if (ecs
->event_thread
->control
.proceed_to_finish
6392 && execution_direction
== EXEC_REVERSE
)
6394 struct thread_info
*tp
= ecs
->event_thread
;
6396 /* We are finishing a function in reverse, and just hit the
6397 step-resume breakpoint at the start address of the
6398 function, and we're almost there -- just need to back up
6399 by one more single-step, which should take us back to the
6401 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6405 fill_in_stop_func (gdbarch
, ecs
);
6406 if (stop_pc
== ecs
->stop_func_start
6407 && execution_direction
== EXEC_REVERSE
)
6409 /* We are stepping over a function call in reverse, and just
6410 hit the step-resume breakpoint at the start address of
6411 the function. Go back to single-stepping, which should
6412 take us back to the function call. */
6413 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6419 case BPSTAT_WHAT_STOP_NOISY
:
6421 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6422 stop_print_frame
= 1;
6424 /* Assume the thread stopped for a breapoint. We'll still check
6425 whether a/the breakpoint is there when the thread is next
6427 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6432 case BPSTAT_WHAT_STOP_SILENT
:
6434 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6435 stop_print_frame
= 0;
6437 /* Assume the thread stopped for a breapoint. We'll still check
6438 whether a/the breakpoint is there when the thread is next
6440 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6444 case BPSTAT_WHAT_HP_STEP_RESUME
:
6446 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6448 delete_step_resume_breakpoint (ecs
->event_thread
);
6449 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6451 /* Back when the step-resume breakpoint was inserted, we
6452 were trying to single-step off a breakpoint. Go back to
6454 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6455 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6461 case BPSTAT_WHAT_KEEP_CHECKING
:
6465 /* If we stepped a permanent breakpoint and we had a high priority
6466 step-resume breakpoint for the address we stepped, but we didn't
6467 hit it, then we must have stepped into the signal handler. The
6468 step-resume was only necessary to catch the case of _not_
6469 stepping into the handler, so delete it, and fall through to
6470 checking whether the step finished. */
6471 if (ecs
->event_thread
->stepped_breakpoint
)
6473 struct breakpoint
*sr_bp
6474 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6477 && sr_bp
->loc
->permanent
6478 && sr_bp
->type
== bp_hp_step_resume
6479 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6482 fprintf_unfiltered (gdb_stdlog
,
6483 "infrun: stepped permanent breakpoint, stopped in "
6485 delete_step_resume_breakpoint (ecs
->event_thread
);
6486 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6490 /* We come here if we hit a breakpoint but should not stop for it.
6491 Possibly we also were stepping and should stop for that. So fall
6492 through and test for stepping. But, if not stepping, do not
6495 /* In all-stop mode, if we're currently stepping but have stopped in
6496 some other thread, we need to switch back to the stepped thread. */
6497 if (switch_back_to_stepped_thread (ecs
))
6500 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6503 fprintf_unfiltered (gdb_stdlog
,
6504 "infrun: step-resume breakpoint is inserted\n");
6506 /* Having a step-resume breakpoint overrides anything
6507 else having to do with stepping commands until
6508 that breakpoint is reached. */
6513 if (ecs
->event_thread
->control
.step_range_end
== 0)
6516 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6517 /* Likewise if we aren't even stepping. */
6522 /* Re-fetch current thread's frame in case the code above caused
6523 the frame cache to be re-initialized, making our FRAME variable
6524 a dangling pointer. */
6525 frame
= get_current_frame ();
6526 gdbarch
= get_frame_arch (frame
);
6527 fill_in_stop_func (gdbarch
, ecs
);
6529 /* If stepping through a line, keep going if still within it.
6531 Note that step_range_end is the address of the first instruction
6532 beyond the step range, and NOT the address of the last instruction
6535 Note also that during reverse execution, we may be stepping
6536 through a function epilogue and therefore must detect when
6537 the current-frame changes in the middle of a line. */
6539 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6540 && (execution_direction
!= EXEC_REVERSE
6541 || frame_id_eq (get_frame_id (frame
),
6542 ecs
->event_thread
->control
.step_frame_id
)))
6546 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6547 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6548 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6550 /* Tentatively re-enable range stepping; `resume' disables it if
6551 necessary (e.g., if we're stepping over a breakpoint or we
6552 have software watchpoints). */
6553 ecs
->event_thread
->control
.may_range_step
= 1;
6555 /* When stepping backward, stop at beginning of line range
6556 (unless it's the function entry point, in which case
6557 keep going back to the call point). */
6558 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6559 && stop_pc
!= ecs
->stop_func_start
6560 && execution_direction
== EXEC_REVERSE
)
6561 end_stepping_range (ecs
);
6568 /* We stepped out of the stepping range. */
6570 /* If we are stepping at the source level and entered the runtime
6571 loader dynamic symbol resolution code...
6573 EXEC_FORWARD: we keep on single stepping until we exit the run
6574 time loader code and reach the callee's address.
6576 EXEC_REVERSE: we've already executed the callee (backward), and
6577 the runtime loader code is handled just like any other
6578 undebuggable function call. Now we need only keep stepping
6579 backward through the trampoline code, and that's handled further
6580 down, so there is nothing for us to do here. */
6582 if (execution_direction
!= EXEC_REVERSE
6583 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6584 && in_solib_dynsym_resolve_code (stop_pc
))
6586 CORE_ADDR pc_after_resolver
=
6587 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6590 fprintf_unfiltered (gdb_stdlog
,
6591 "infrun: stepped into dynsym resolve code\n");
6593 if (pc_after_resolver
)
6595 /* Set up a step-resume breakpoint at the address
6596 indicated by SKIP_SOLIB_RESOLVER. */
6597 struct symtab_and_line sr_sal
;
6600 sr_sal
.pc
= pc_after_resolver
;
6601 sr_sal
.pspace
= get_frame_program_space (frame
);
6603 insert_step_resume_breakpoint_at_sal (gdbarch
,
6604 sr_sal
, null_frame_id
);
6611 if (ecs
->event_thread
->control
.step_range_end
!= 1
6612 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6613 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6614 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6617 fprintf_unfiltered (gdb_stdlog
,
6618 "infrun: stepped into signal trampoline\n");
6619 /* The inferior, while doing a "step" or "next", has ended up in
6620 a signal trampoline (either by a signal being delivered or by
6621 the signal handler returning). Just single-step until the
6622 inferior leaves the trampoline (either by calling the handler
6628 /* If we're in the return path from a shared library trampoline,
6629 we want to proceed through the trampoline when stepping. */
6630 /* macro/2012-04-25: This needs to come before the subroutine
6631 call check below as on some targets return trampolines look
6632 like subroutine calls (MIPS16 return thunks). */
6633 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6634 stop_pc
, ecs
->stop_func_name
)
6635 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6637 /* Determine where this trampoline returns. */
6638 CORE_ADDR real_stop_pc
;
6640 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6643 fprintf_unfiltered (gdb_stdlog
,
6644 "infrun: stepped into solib return tramp\n");
6646 /* Only proceed through if we know where it's going. */
6649 /* And put the step-breakpoint there and go until there. */
6650 struct symtab_and_line sr_sal
;
6652 init_sal (&sr_sal
); /* initialize to zeroes */
6653 sr_sal
.pc
= real_stop_pc
;
6654 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6655 sr_sal
.pspace
= get_frame_program_space (frame
);
6657 /* Do not specify what the fp should be when we stop since
6658 on some machines the prologue is where the new fp value
6660 insert_step_resume_breakpoint_at_sal (gdbarch
,
6661 sr_sal
, null_frame_id
);
6663 /* Restart without fiddling with the step ranges or
6670 /* Check for subroutine calls. The check for the current frame
6671 equalling the step ID is not necessary - the check of the
6672 previous frame's ID is sufficient - but it is a common case and
6673 cheaper than checking the previous frame's ID.
6675 NOTE: frame_id_eq will never report two invalid frame IDs as
6676 being equal, so to get into this block, both the current and
6677 previous frame must have valid frame IDs. */
6678 /* The outer_frame_id check is a heuristic to detect stepping
6679 through startup code. If we step over an instruction which
6680 sets the stack pointer from an invalid value to a valid value,
6681 we may detect that as a subroutine call from the mythical
6682 "outermost" function. This could be fixed by marking
6683 outermost frames as !stack_p,code_p,special_p. Then the
6684 initial outermost frame, before sp was valid, would
6685 have code_addr == &_start. See the comment in frame_id_eq
6687 if (!frame_id_eq (get_stack_frame_id (frame
),
6688 ecs
->event_thread
->control
.step_stack_frame_id
)
6689 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6690 ecs
->event_thread
->control
.step_stack_frame_id
)
6691 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6693 || (ecs
->event_thread
->control
.step_start_function
6694 != find_pc_function (stop_pc
)))))
6696 CORE_ADDR real_stop_pc
;
6699 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6701 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6703 /* I presume that step_over_calls is only 0 when we're
6704 supposed to be stepping at the assembly language level
6705 ("stepi"). Just stop. */
6706 /* And this works the same backward as frontward. MVS */
6707 end_stepping_range (ecs
);
6711 /* Reverse stepping through solib trampolines. */
6713 if (execution_direction
== EXEC_REVERSE
6714 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6715 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6716 || (ecs
->stop_func_start
== 0
6717 && in_solib_dynsym_resolve_code (stop_pc
))))
6719 /* Any solib trampoline code can be handled in reverse
6720 by simply continuing to single-step. We have already
6721 executed the solib function (backwards), and a few
6722 steps will take us back through the trampoline to the
6728 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6730 /* We're doing a "next".
6732 Normal (forward) execution: set a breakpoint at the
6733 callee's return address (the address at which the caller
6736 Reverse (backward) execution. set the step-resume
6737 breakpoint at the start of the function that we just
6738 stepped into (backwards), and continue to there. When we
6739 get there, we'll need to single-step back to the caller. */
6741 if (execution_direction
== EXEC_REVERSE
)
6743 /* If we're already at the start of the function, we've either
6744 just stepped backward into a single instruction function,
6745 or stepped back out of a signal handler to the first instruction
6746 of the function. Just keep going, which will single-step back
6748 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6750 struct symtab_and_line sr_sal
;
6752 /* Normal function call return (static or dynamic). */
6754 sr_sal
.pc
= ecs
->stop_func_start
;
6755 sr_sal
.pspace
= get_frame_program_space (frame
);
6756 insert_step_resume_breakpoint_at_sal (gdbarch
,
6757 sr_sal
, null_frame_id
);
6761 insert_step_resume_breakpoint_at_caller (frame
);
6767 /* If we are in a function call trampoline (a stub between the
6768 calling routine and the real function), locate the real
6769 function. That's what tells us (a) whether we want to step
6770 into it at all, and (b) what prologue we want to run to the
6771 end of, if we do step into it. */
6772 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6773 if (real_stop_pc
== 0)
6774 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6775 if (real_stop_pc
!= 0)
6776 ecs
->stop_func_start
= real_stop_pc
;
6778 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6780 struct symtab_and_line sr_sal
;
6783 sr_sal
.pc
= ecs
->stop_func_start
;
6784 sr_sal
.pspace
= get_frame_program_space (frame
);
6786 insert_step_resume_breakpoint_at_sal (gdbarch
,
6787 sr_sal
, null_frame_id
);
6792 /* If we have line number information for the function we are
6793 thinking of stepping into and the function isn't on the skip
6796 If there are several symtabs at that PC (e.g. with include
6797 files), just want to know whether *any* of them have line
6798 numbers. find_pc_line handles this. */
6800 struct symtab_and_line tmp_sal
;
6802 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6803 if (tmp_sal
.line
!= 0
6804 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6807 if (execution_direction
== EXEC_REVERSE
)
6808 handle_step_into_function_backward (gdbarch
, ecs
);
6810 handle_step_into_function (gdbarch
, ecs
);
6815 /* If we have no line number and the step-stop-if-no-debug is
6816 set, we stop the step so that the user has a chance to switch
6817 in assembly mode. */
6818 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6819 && step_stop_if_no_debug
)
6821 end_stepping_range (ecs
);
6825 if (execution_direction
== EXEC_REVERSE
)
6827 /* If we're already at the start of the function, we've either just
6828 stepped backward into a single instruction function without line
6829 number info, or stepped back out of a signal handler to the first
6830 instruction of the function without line number info. Just keep
6831 going, which will single-step back to the caller. */
6832 if (ecs
->stop_func_start
!= stop_pc
)
6834 /* Set a breakpoint at callee's start address.
6835 From there we can step once and be back in the caller. */
6836 struct symtab_and_line sr_sal
;
6839 sr_sal
.pc
= ecs
->stop_func_start
;
6840 sr_sal
.pspace
= get_frame_program_space (frame
);
6841 insert_step_resume_breakpoint_at_sal (gdbarch
,
6842 sr_sal
, null_frame_id
);
6846 /* Set a breakpoint at callee's return address (the address
6847 at which the caller will resume). */
6848 insert_step_resume_breakpoint_at_caller (frame
);
6854 /* Reverse stepping through solib trampolines. */
6856 if (execution_direction
== EXEC_REVERSE
6857 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6859 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6860 || (ecs
->stop_func_start
== 0
6861 && in_solib_dynsym_resolve_code (stop_pc
)))
6863 /* Any solib trampoline code can be handled in reverse
6864 by simply continuing to single-step. We have already
6865 executed the solib function (backwards), and a few
6866 steps will take us back through the trampoline to the
6871 else if (in_solib_dynsym_resolve_code (stop_pc
))
6873 /* Stepped backward into the solib dynsym resolver.
6874 Set a breakpoint at its start and continue, then
6875 one more step will take us out. */
6876 struct symtab_and_line sr_sal
;
6879 sr_sal
.pc
= ecs
->stop_func_start
;
6880 sr_sal
.pspace
= get_frame_program_space (frame
);
6881 insert_step_resume_breakpoint_at_sal (gdbarch
,
6882 sr_sal
, null_frame_id
);
6888 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6890 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6891 the trampoline processing logic, however, there are some trampolines
6892 that have no names, so we should do trampoline handling first. */
6893 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6894 && ecs
->stop_func_name
== NULL
6895 && stop_pc_sal
.line
== 0)
6898 fprintf_unfiltered (gdb_stdlog
,
6899 "infrun: stepped into undebuggable function\n");
6901 /* The inferior just stepped into, or returned to, an
6902 undebuggable function (where there is no debugging information
6903 and no line number corresponding to the address where the
6904 inferior stopped). Since we want to skip this kind of code,
6905 we keep going until the inferior returns from this
6906 function - unless the user has asked us not to (via
6907 set step-mode) or we no longer know how to get back
6908 to the call site. */
6909 if (step_stop_if_no_debug
6910 || !frame_id_p (frame_unwind_caller_id (frame
)))
6912 /* If we have no line number and the step-stop-if-no-debug
6913 is set, we stop the step so that the user has a chance to
6914 switch in assembly mode. */
6915 end_stepping_range (ecs
);
6920 /* Set a breakpoint at callee's return address (the address
6921 at which the caller will resume). */
6922 insert_step_resume_breakpoint_at_caller (frame
);
6928 if (ecs
->event_thread
->control
.step_range_end
== 1)
6930 /* It is stepi or nexti. We always want to stop stepping after
6933 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6934 end_stepping_range (ecs
);
6938 if (stop_pc_sal
.line
== 0)
6940 /* We have no line number information. That means to stop
6941 stepping (does this always happen right after one instruction,
6942 when we do "s" in a function with no line numbers,
6943 or can this happen as a result of a return or longjmp?). */
6945 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6946 end_stepping_range (ecs
);
6950 /* Look for "calls" to inlined functions, part one. If the inline
6951 frame machinery detected some skipped call sites, we have entered
6952 a new inline function. */
6954 if (frame_id_eq (get_frame_id (get_current_frame ()),
6955 ecs
->event_thread
->control
.step_frame_id
)
6956 && inline_skipped_frames (ecs
->ptid
))
6958 struct symtab_and_line call_sal
;
6961 fprintf_unfiltered (gdb_stdlog
,
6962 "infrun: stepped into inlined function\n");
6964 find_frame_sal (get_current_frame (), &call_sal
);
6966 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6968 /* For "step", we're going to stop. But if the call site
6969 for this inlined function is on the same source line as
6970 we were previously stepping, go down into the function
6971 first. Otherwise stop at the call site. */
6973 if (call_sal
.line
== ecs
->event_thread
->current_line
6974 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6975 step_into_inline_frame (ecs
->ptid
);
6977 end_stepping_range (ecs
);
6982 /* For "next", we should stop at the call site if it is on a
6983 different source line. Otherwise continue through the
6984 inlined function. */
6985 if (call_sal
.line
== ecs
->event_thread
->current_line
6986 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6989 end_stepping_range (ecs
);
6994 /* Look for "calls" to inlined functions, part two. If we are still
6995 in the same real function we were stepping through, but we have
6996 to go further up to find the exact frame ID, we are stepping
6997 through a more inlined call beyond its call site. */
6999 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
7000 && !frame_id_eq (get_frame_id (get_current_frame ()),
7001 ecs
->event_thread
->control
.step_frame_id
)
7002 && stepped_in_from (get_current_frame (),
7003 ecs
->event_thread
->control
.step_frame_id
))
7006 fprintf_unfiltered (gdb_stdlog
,
7007 "infrun: stepping through inlined function\n");
7009 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
7012 end_stepping_range (ecs
);
7016 if ((stop_pc
== stop_pc_sal
.pc
)
7017 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
7018 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
7020 /* We are at the start of a different line. So stop. Note that
7021 we don't stop if we step into the middle of a different line.
7022 That is said to make things like for (;;) statements work
7025 fprintf_unfiltered (gdb_stdlog
,
7026 "infrun: stepped to a different line\n");
7027 end_stepping_range (ecs
);
7031 /* We aren't done stepping.
7033 Optimize by setting the stepping range to the line.
7034 (We might not be in the original line, but if we entered a
7035 new line in mid-statement, we continue stepping. This makes
7036 things like for(;;) statements work better.) */
7038 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7039 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7040 ecs
->event_thread
->control
.may_range_step
= 1;
7041 set_step_info (frame
, stop_pc_sal
);
7044 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
7048 /* In all-stop mode, if we're currently stepping but have stopped in
7049 some other thread, we may need to switch back to the stepped
7050 thread. Returns true we set the inferior running, false if we left
7051 it stopped (and the event needs further processing). */
7054 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7056 if (!target_is_non_stop_p ())
7058 struct thread_info
*tp
;
7059 struct thread_info
*stepping_thread
;
7061 /* If any thread is blocked on some internal breakpoint, and we
7062 simply need to step over that breakpoint to get it going
7063 again, do that first. */
7065 /* However, if we see an event for the stepping thread, then we
7066 know all other threads have been moved past their breakpoints
7067 already. Let the caller check whether the step is finished,
7068 etc., before deciding to move it past a breakpoint. */
7069 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7072 /* Check if the current thread is blocked on an incomplete
7073 step-over, interrupted by a random signal. */
7074 if (ecs
->event_thread
->control
.trap_expected
7075 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7079 fprintf_unfiltered (gdb_stdlog
,
7080 "infrun: need to finish step-over of [%s]\n",
7081 target_pid_to_str (ecs
->event_thread
->ptid
));
7087 /* Check if the current thread is blocked by a single-step
7088 breakpoint of another thread. */
7089 if (ecs
->hit_singlestep_breakpoint
)
7093 fprintf_unfiltered (gdb_stdlog
,
7094 "infrun: need to step [%s] over single-step "
7096 target_pid_to_str (ecs
->ptid
));
7102 /* If this thread needs yet another step-over (e.g., stepping
7103 through a delay slot), do it first before moving on to
7105 if (thread_still_needs_step_over (ecs
->event_thread
))
7109 fprintf_unfiltered (gdb_stdlog
,
7110 "infrun: thread [%s] still needs step-over\n",
7111 target_pid_to_str (ecs
->event_thread
->ptid
));
7117 /* If scheduler locking applies even if not stepping, there's no
7118 need to walk over threads. Above we've checked whether the
7119 current thread is stepping. If some other thread not the
7120 event thread is stepping, then it must be that scheduler
7121 locking is not in effect. */
7122 if (schedlock_applies (ecs
->event_thread
))
7125 /* Otherwise, we no longer expect a trap in the current thread.
7126 Clear the trap_expected flag before switching back -- this is
7127 what keep_going does as well, if we call it. */
7128 ecs
->event_thread
->control
.trap_expected
= 0;
7130 /* Likewise, clear the signal if it should not be passed. */
7131 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7132 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7134 /* Do all pending step-overs before actually proceeding with
7136 if (start_step_over ())
7138 prepare_to_wait (ecs
);
7142 /* Look for the stepping/nexting thread. */
7143 stepping_thread
= NULL
;
7145 ALL_NON_EXITED_THREADS (tp
)
7147 /* Ignore threads of processes the caller is not
7150 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
7153 /* When stepping over a breakpoint, we lock all threads
7154 except the one that needs to move past the breakpoint.
7155 If a non-event thread has this set, the "incomplete
7156 step-over" check above should have caught it earlier. */
7157 if (tp
->control
.trap_expected
)
7159 internal_error (__FILE__
, __LINE__
,
7160 "[%s] has inconsistent state: "
7161 "trap_expected=%d\n",
7162 target_pid_to_str (tp
->ptid
),
7163 tp
->control
.trap_expected
);
7166 /* Did we find the stepping thread? */
7167 if (tp
->control
.step_range_end
)
7169 /* Yep. There should only one though. */
7170 gdb_assert (stepping_thread
== NULL
);
7172 /* The event thread is handled at the top, before we
7174 gdb_assert (tp
!= ecs
->event_thread
);
7176 /* If some thread other than the event thread is
7177 stepping, then scheduler locking can't be in effect,
7178 otherwise we wouldn't have resumed the current event
7179 thread in the first place. */
7180 gdb_assert (!schedlock_applies (tp
));
7182 stepping_thread
= tp
;
7186 if (stepping_thread
!= NULL
)
7189 fprintf_unfiltered (gdb_stdlog
,
7190 "infrun: switching back to stepped thread\n");
7192 if (keep_going_stepped_thread (stepping_thread
))
7194 prepare_to_wait (ecs
);
7203 /* Set a previously stepped thread back to stepping. Returns true on
7204 success, false if the resume is not possible (e.g., the thread
7208 keep_going_stepped_thread (struct thread_info
*tp
)
7210 struct frame_info
*frame
;
7211 struct execution_control_state ecss
;
7212 struct execution_control_state
*ecs
= &ecss
;
7214 /* If the stepping thread exited, then don't try to switch back and
7215 resume it, which could fail in several different ways depending
7216 on the target. Instead, just keep going.
7218 We can find a stepping dead thread in the thread list in two
7221 - The target supports thread exit events, and when the target
7222 tries to delete the thread from the thread list, inferior_ptid
7223 pointed at the exiting thread. In such case, calling
7224 delete_thread does not really remove the thread from the list;
7225 instead, the thread is left listed, with 'exited' state.
7227 - The target's debug interface does not support thread exit
7228 events, and so we have no idea whatsoever if the previously
7229 stepping thread is still alive. For that reason, we need to
7230 synchronously query the target now. */
7232 if (is_exited (tp
->ptid
)
7233 || !target_thread_alive (tp
->ptid
))
7236 fprintf_unfiltered (gdb_stdlog
,
7237 "infrun: not resuming previously "
7238 "stepped thread, it has vanished\n");
7240 delete_thread (tp
->ptid
);
7245 fprintf_unfiltered (gdb_stdlog
,
7246 "infrun: resuming previously stepped thread\n");
7248 reset_ecs (ecs
, tp
);
7249 switch_to_thread (tp
->ptid
);
7251 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
7252 frame
= get_current_frame ();
7254 /* If the PC of the thread we were trying to single-step has
7255 changed, then that thread has trapped or been signaled, but the
7256 event has not been reported to GDB yet. Re-poll the target
7257 looking for this particular thread's event (i.e. temporarily
7258 enable schedlock) by:
7260 - setting a break at the current PC
7261 - resuming that particular thread, only (by setting trap
7264 This prevents us continuously moving the single-step breakpoint
7265 forward, one instruction at a time, overstepping. */
7267 if (stop_pc
!= tp
->prev_pc
)
7272 fprintf_unfiltered (gdb_stdlog
,
7273 "infrun: expected thread advanced also (%s -> %s)\n",
7274 paddress (target_gdbarch (), tp
->prev_pc
),
7275 paddress (target_gdbarch (), stop_pc
));
7277 /* Clear the info of the previous step-over, as it's no longer
7278 valid (if the thread was trying to step over a breakpoint, it
7279 has already succeeded). It's what keep_going would do too,
7280 if we called it. Do this before trying to insert the sss
7281 breakpoint, otherwise if we were previously trying to step
7282 over this exact address in another thread, the breakpoint is
7284 clear_step_over_info ();
7285 tp
->control
.trap_expected
= 0;
7287 insert_single_step_breakpoint (get_frame_arch (frame
),
7288 get_frame_address_space (frame
),
7292 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7293 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7298 fprintf_unfiltered (gdb_stdlog
,
7299 "infrun: expected thread still hasn't advanced\n");
7301 keep_going_pass_signal (ecs
);
7306 /* Is thread TP in the middle of (software or hardware)
7307 single-stepping? (Note the result of this function must never be
7308 passed directly as target_resume's STEP parameter.) */
7311 currently_stepping (struct thread_info
*tp
)
7313 return ((tp
->control
.step_range_end
7314 && tp
->control
.step_resume_breakpoint
== NULL
)
7315 || tp
->control
.trap_expected
7316 || tp
->stepped_breakpoint
7317 || bpstat_should_step ());
7320 /* Inferior has stepped into a subroutine call with source code that
7321 we should not step over. Do step to the first line of code in
7325 handle_step_into_function (struct gdbarch
*gdbarch
,
7326 struct execution_control_state
*ecs
)
7328 struct compunit_symtab
*cust
;
7329 struct symtab_and_line stop_func_sal
, sr_sal
;
7331 fill_in_stop_func (gdbarch
, ecs
);
7333 cust
= find_pc_compunit_symtab (stop_pc
);
7334 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7335 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7336 ecs
->stop_func_start
);
7338 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7339 /* Use the step_resume_break to step until the end of the prologue,
7340 even if that involves jumps (as it seems to on the vax under
7342 /* If the prologue ends in the middle of a source line, continue to
7343 the end of that source line (if it is still within the function).
7344 Otherwise, just go to end of prologue. */
7345 if (stop_func_sal
.end
7346 && stop_func_sal
.pc
!= ecs
->stop_func_start
7347 && stop_func_sal
.end
< ecs
->stop_func_end
)
7348 ecs
->stop_func_start
= stop_func_sal
.end
;
7350 /* Architectures which require breakpoint adjustment might not be able
7351 to place a breakpoint at the computed address. If so, the test
7352 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7353 ecs->stop_func_start to an address at which a breakpoint may be
7354 legitimately placed.
7356 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7357 made, GDB will enter an infinite loop when stepping through
7358 optimized code consisting of VLIW instructions which contain
7359 subinstructions corresponding to different source lines. On
7360 FR-V, it's not permitted to place a breakpoint on any but the
7361 first subinstruction of a VLIW instruction. When a breakpoint is
7362 set, GDB will adjust the breakpoint address to the beginning of
7363 the VLIW instruction. Thus, we need to make the corresponding
7364 adjustment here when computing the stop address. */
7366 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7368 ecs
->stop_func_start
7369 = gdbarch_adjust_breakpoint_address (gdbarch
,
7370 ecs
->stop_func_start
);
7373 if (ecs
->stop_func_start
== stop_pc
)
7375 /* We are already there: stop now. */
7376 end_stepping_range (ecs
);
7381 /* Put the step-breakpoint there and go until there. */
7382 init_sal (&sr_sal
); /* initialize to zeroes */
7383 sr_sal
.pc
= ecs
->stop_func_start
;
7384 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7385 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7387 /* Do not specify what the fp should be when we stop since on
7388 some machines the prologue is where the new fp value is
7390 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7392 /* And make sure stepping stops right away then. */
7393 ecs
->event_thread
->control
.step_range_end
7394 = ecs
->event_thread
->control
.step_range_start
;
7399 /* Inferior has stepped backward into a subroutine call with source
7400 code that we should not step over. Do step to the beginning of the
7401 last line of code in it. */
7404 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7405 struct execution_control_state
*ecs
)
7407 struct compunit_symtab
*cust
;
7408 struct symtab_and_line stop_func_sal
;
7410 fill_in_stop_func (gdbarch
, ecs
);
7412 cust
= find_pc_compunit_symtab (stop_pc
);
7413 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7414 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
7415 ecs
->stop_func_start
);
7417 stop_func_sal
= find_pc_line (stop_pc
, 0);
7419 /* OK, we're just going to keep stepping here. */
7420 if (stop_func_sal
.pc
== stop_pc
)
7422 /* We're there already. Just stop stepping now. */
7423 end_stepping_range (ecs
);
7427 /* Else just reset the step range and keep going.
7428 No step-resume breakpoint, they don't work for
7429 epilogues, which can have multiple entry paths. */
7430 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7431 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7437 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7438 This is used to both functions and to skip over code. */
7441 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7442 struct symtab_and_line sr_sal
,
7443 struct frame_id sr_id
,
7444 enum bptype sr_type
)
7446 /* There should never be more than one step-resume or longjmp-resume
7447 breakpoint per thread, so we should never be setting a new
7448 step_resume_breakpoint when one is already active. */
7449 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7450 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7453 fprintf_unfiltered (gdb_stdlog
,
7454 "infrun: inserting step-resume breakpoint at %s\n",
7455 paddress (gdbarch
, sr_sal
.pc
));
7457 inferior_thread ()->control
.step_resume_breakpoint
7458 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
7462 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7463 struct symtab_and_line sr_sal
,
7464 struct frame_id sr_id
)
7466 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7471 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7472 This is used to skip a potential signal handler.
7474 This is called with the interrupted function's frame. The signal
7475 handler, when it returns, will resume the interrupted function at
7479 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7481 struct symtab_and_line sr_sal
;
7482 struct gdbarch
*gdbarch
;
7484 gdb_assert (return_frame
!= NULL
);
7485 init_sal (&sr_sal
); /* initialize to zeros */
7487 gdbarch
= get_frame_arch (return_frame
);
7488 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7489 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7490 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7492 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7493 get_stack_frame_id (return_frame
),
7497 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7498 is used to skip a function after stepping into it (for "next" or if
7499 the called function has no debugging information).
7501 The current function has almost always been reached by single
7502 stepping a call or return instruction. NEXT_FRAME belongs to the
7503 current function, and the breakpoint will be set at the caller's
7506 This is a separate function rather than reusing
7507 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7508 get_prev_frame, which may stop prematurely (see the implementation
7509 of frame_unwind_caller_id for an example). */
7512 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7514 struct symtab_and_line sr_sal
;
7515 struct gdbarch
*gdbarch
;
7517 /* We shouldn't have gotten here if we don't know where the call site
7519 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7521 init_sal (&sr_sal
); /* initialize to zeros */
7523 gdbarch
= frame_unwind_caller_arch (next_frame
);
7524 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7525 frame_unwind_caller_pc (next_frame
));
7526 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7527 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7529 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7530 frame_unwind_caller_id (next_frame
));
7533 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7534 new breakpoint at the target of a jmp_buf. The handling of
7535 longjmp-resume uses the same mechanisms used for handling
7536 "step-resume" breakpoints. */
7539 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7541 /* There should never be more than one longjmp-resume breakpoint per
7542 thread, so we should never be setting a new
7543 longjmp_resume_breakpoint when one is already active. */
7544 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7547 fprintf_unfiltered (gdb_stdlog
,
7548 "infrun: inserting longjmp-resume breakpoint at %s\n",
7549 paddress (gdbarch
, pc
));
7551 inferior_thread ()->control
.exception_resume_breakpoint
=
7552 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
7555 /* Insert an exception resume breakpoint. TP is the thread throwing
7556 the exception. The block B is the block of the unwinder debug hook
7557 function. FRAME is the frame corresponding to the call to this
7558 function. SYM is the symbol of the function argument holding the
7559 target PC of the exception. */
7562 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7563 const struct block
*b
,
7564 struct frame_info
*frame
,
7569 struct block_symbol vsym
;
7570 struct value
*value
;
7572 struct breakpoint
*bp
;
7574 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
7575 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7576 /* If the value was optimized out, revert to the old behavior. */
7577 if (! value_optimized_out (value
))
7579 handler
= value_as_address (value
);
7582 fprintf_unfiltered (gdb_stdlog
,
7583 "infrun: exception resume at %lx\n",
7584 (unsigned long) handler
);
7586 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7587 handler
, bp_exception_resume
);
7589 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7592 bp
->thread
= tp
->global_num
;
7593 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7596 CATCH (e
, RETURN_MASK_ERROR
)
7598 /* We want to ignore errors here. */
7603 /* A helper for check_exception_resume that sets an
7604 exception-breakpoint based on a SystemTap probe. */
7607 insert_exception_resume_from_probe (struct thread_info
*tp
,
7608 const struct bound_probe
*probe
,
7609 struct frame_info
*frame
)
7611 struct value
*arg_value
;
7613 struct breakpoint
*bp
;
7615 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7619 handler
= value_as_address (arg_value
);
7622 fprintf_unfiltered (gdb_stdlog
,
7623 "infrun: exception resume at %s\n",
7624 paddress (get_objfile_arch (probe
->objfile
),
7627 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7628 handler
, bp_exception_resume
);
7629 bp
->thread
= tp
->global_num
;
7630 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7633 /* This is called when an exception has been intercepted. Check to
7634 see whether the exception's destination is of interest, and if so,
7635 set an exception resume breakpoint there. */
7638 check_exception_resume (struct execution_control_state
*ecs
,
7639 struct frame_info
*frame
)
7641 struct bound_probe probe
;
7642 struct symbol
*func
;
7644 /* First see if this exception unwinding breakpoint was set via a
7645 SystemTap probe point. If so, the probe has two arguments: the
7646 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7647 set a breakpoint there. */
7648 probe
= find_probe_by_pc (get_frame_pc (frame
));
7651 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7655 func
= get_frame_function (frame
);
7661 const struct block
*b
;
7662 struct block_iterator iter
;
7666 /* The exception breakpoint is a thread-specific breakpoint on
7667 the unwinder's debug hook, declared as:
7669 void _Unwind_DebugHook (void *cfa, void *handler);
7671 The CFA argument indicates the frame to which control is
7672 about to be transferred. HANDLER is the destination PC.
7674 We ignore the CFA and set a temporary breakpoint at HANDLER.
7675 This is not extremely efficient but it avoids issues in gdb
7676 with computing the DWARF CFA, and it also works even in weird
7677 cases such as throwing an exception from inside a signal
7680 b
= SYMBOL_BLOCK_VALUE (func
);
7681 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7683 if (!SYMBOL_IS_ARGUMENT (sym
))
7690 insert_exception_resume_breakpoint (ecs
->event_thread
,
7696 CATCH (e
, RETURN_MASK_ERROR
)
7703 stop_waiting (struct execution_control_state
*ecs
)
7706 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7708 clear_step_over_info ();
7710 /* Let callers know we don't want to wait for the inferior anymore. */
7711 ecs
->wait_some_more
= 0;
7713 /* If all-stop, but the target is always in non-stop mode, stop all
7714 threads now that we're presenting the stop to the user. */
7715 if (!non_stop
&& target_is_non_stop_p ())
7716 stop_all_threads ();
7719 /* Like keep_going, but passes the signal to the inferior, even if the
7720 signal is set to nopass. */
7723 keep_going_pass_signal (struct execution_control_state
*ecs
)
7725 /* Make sure normal_stop is called if we get a QUIT handled before
7727 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
7729 gdb_assert (ptid_equal (ecs
->event_thread
->ptid
, inferior_ptid
));
7730 gdb_assert (!ecs
->event_thread
->resumed
);
7732 /* Save the pc before execution, to compare with pc after stop. */
7733 ecs
->event_thread
->prev_pc
7734 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
7736 if (ecs
->event_thread
->control
.trap_expected
)
7738 struct thread_info
*tp
= ecs
->event_thread
;
7741 fprintf_unfiltered (gdb_stdlog
,
7742 "infrun: %s has trap_expected set, "
7743 "resuming to collect trap\n",
7744 target_pid_to_str (tp
->ptid
));
7746 /* We haven't yet gotten our trap, and either: intercepted a
7747 non-signal event (e.g., a fork); or took a signal which we
7748 are supposed to pass through to the inferior. Simply
7750 discard_cleanups (old_cleanups
);
7751 resume (ecs
->event_thread
->suspend
.stop_signal
);
7753 else if (step_over_info_valid_p ())
7755 /* Another thread is stepping over a breakpoint in-line. If
7756 this thread needs a step-over too, queue the request. In
7757 either case, this resume must be deferred for later. */
7758 struct thread_info
*tp
= ecs
->event_thread
;
7760 if (ecs
->hit_singlestep_breakpoint
7761 || thread_still_needs_step_over (tp
))
7764 fprintf_unfiltered (gdb_stdlog
,
7765 "infrun: step-over already in progress: "
7766 "step-over for %s deferred\n",
7767 target_pid_to_str (tp
->ptid
));
7768 thread_step_over_chain_enqueue (tp
);
7773 fprintf_unfiltered (gdb_stdlog
,
7774 "infrun: step-over in progress: "
7775 "resume of %s deferred\n",
7776 target_pid_to_str (tp
->ptid
));
7779 discard_cleanups (old_cleanups
);
7783 struct regcache
*regcache
= get_current_regcache ();
7786 step_over_what step_what
;
7788 /* Either the trap was not expected, but we are continuing
7789 anyway (if we got a signal, the user asked it be passed to
7792 We got our expected trap, but decided we should resume from
7795 We're going to run this baby now!
7797 Note that insert_breakpoints won't try to re-insert
7798 already inserted breakpoints. Therefore, we don't
7799 care if breakpoints were already inserted, or not. */
7801 /* If we need to step over a breakpoint, and we're not using
7802 displaced stepping to do so, insert all breakpoints
7803 (watchpoints, etc.) but the one we're stepping over, step one
7804 instruction, and then re-insert the breakpoint when that step
7807 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7809 remove_bp
= (ecs
->hit_singlestep_breakpoint
7810 || (step_what
& STEP_OVER_BREAKPOINT
));
7811 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7813 /* We can't use displaced stepping if we need to step past a
7814 watchpoint. The instruction copied to the scratch pad would
7815 still trigger the watchpoint. */
7817 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7819 set_step_over_info (get_regcache_aspace (regcache
),
7820 regcache_read_pc (regcache
), remove_wps
,
7821 ecs
->event_thread
->global_num
);
7823 else if (remove_wps
)
7824 set_step_over_info (NULL
, 0, remove_wps
, -1);
7826 /* If we now need to do an in-line step-over, we need to stop
7827 all other threads. Note this must be done before
7828 insert_breakpoints below, because that removes the breakpoint
7829 we're about to step over, otherwise other threads could miss
7831 if (step_over_info_valid_p () && target_is_non_stop_p ())
7832 stop_all_threads ();
7834 /* Stop stepping if inserting breakpoints fails. */
7837 insert_breakpoints ();
7839 CATCH (e
, RETURN_MASK_ERROR
)
7841 exception_print (gdb_stderr
, e
);
7843 discard_cleanups (old_cleanups
);
7848 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7850 discard_cleanups (old_cleanups
);
7851 resume (ecs
->event_thread
->suspend
.stop_signal
);
7854 prepare_to_wait (ecs
);
7857 /* Called when we should continue running the inferior, because the
7858 current event doesn't cause a user visible stop. This does the
7859 resuming part; waiting for the next event is done elsewhere. */
7862 keep_going (struct execution_control_state
*ecs
)
7864 if (ecs
->event_thread
->control
.trap_expected
7865 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7866 ecs
->event_thread
->control
.trap_expected
= 0;
7868 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7869 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7870 keep_going_pass_signal (ecs
);
7873 /* This function normally comes after a resume, before
7874 handle_inferior_event exits. It takes care of any last bits of
7875 housekeeping, and sets the all-important wait_some_more flag. */
7878 prepare_to_wait (struct execution_control_state
*ecs
)
7881 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7883 ecs
->wait_some_more
= 1;
7885 if (!target_is_async_p ())
7886 mark_infrun_async_event_handler ();
7889 /* We are done with the step range of a step/next/si/ni command.
7890 Called once for each n of a "step n" operation. */
7893 end_stepping_range (struct execution_control_state
*ecs
)
7895 ecs
->event_thread
->control
.stop_step
= 1;
7899 /* Several print_*_reason functions to print why the inferior has stopped.
7900 We always print something when the inferior exits, or receives a signal.
7901 The rest of the cases are dealt with later on in normal_stop and
7902 print_it_typical. Ideally there should be a call to one of these
7903 print_*_reason functions functions from handle_inferior_event each time
7904 stop_waiting is called.
7906 Note that we don't call these directly, instead we delegate that to
7907 the interpreters, through observers. Interpreters then call these
7908 with whatever uiout is right. */
7911 print_end_stepping_range_reason (struct ui_out
*uiout
)
7913 /* For CLI-like interpreters, print nothing. */
7915 if (ui_out_is_mi_like_p (uiout
))
7917 ui_out_field_string (uiout
, "reason",
7918 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7923 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7925 annotate_signalled ();
7926 if (ui_out_is_mi_like_p (uiout
))
7928 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7929 ui_out_text (uiout
, "\nProgram terminated with signal ");
7930 annotate_signal_name ();
7931 ui_out_field_string (uiout
, "signal-name",
7932 gdb_signal_to_name (siggnal
));
7933 annotate_signal_name_end ();
7934 ui_out_text (uiout
, ", ");
7935 annotate_signal_string ();
7936 ui_out_field_string (uiout
, "signal-meaning",
7937 gdb_signal_to_string (siggnal
));
7938 annotate_signal_string_end ();
7939 ui_out_text (uiout
, ".\n");
7940 ui_out_text (uiout
, "The program no longer exists.\n");
7944 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7946 struct inferior
*inf
= current_inferior ();
7947 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
7949 annotate_exited (exitstatus
);
7952 if (ui_out_is_mi_like_p (uiout
))
7953 ui_out_field_string (uiout
, "reason",
7954 async_reason_lookup (EXEC_ASYNC_EXITED
));
7955 ui_out_text (uiout
, "[Inferior ");
7956 ui_out_text (uiout
, plongest (inf
->num
));
7957 ui_out_text (uiout
, " (");
7958 ui_out_text (uiout
, pidstr
);
7959 ui_out_text (uiout
, ") exited with code ");
7960 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
7961 ui_out_text (uiout
, "]\n");
7965 if (ui_out_is_mi_like_p (uiout
))
7967 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7968 ui_out_text (uiout
, "[Inferior ");
7969 ui_out_text (uiout
, plongest (inf
->num
));
7970 ui_out_text (uiout
, " (");
7971 ui_out_text (uiout
, pidstr
);
7972 ui_out_text (uiout
, ") exited normally]\n");
7976 /* Some targets/architectures can do extra processing/display of
7977 segmentation faults. E.g., Intel MPX boundary faults.
7978 Call the architecture dependent function to handle the fault. */
7981 handle_segmentation_fault (struct ui_out
*uiout
)
7983 struct regcache
*regcache
= get_current_regcache ();
7984 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7986 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7987 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7991 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7993 struct thread_info
*thr
= inferior_thread ();
7997 if (ui_out_is_mi_like_p (uiout
))
7999 else if (show_thread_that_caused_stop ())
8003 ui_out_text (uiout
, "\nThread ");
8004 ui_out_field_fmt (uiout
, "thread-id", "%s", print_thread_id (thr
));
8006 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
8009 ui_out_text (uiout
, " \"");
8010 ui_out_field_fmt (uiout
, "name", "%s", name
);
8011 ui_out_text (uiout
, "\"");
8015 ui_out_text (uiout
, "\nProgram");
8017 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
8018 ui_out_text (uiout
, " stopped");
8021 ui_out_text (uiout
, " received signal ");
8022 annotate_signal_name ();
8023 if (ui_out_is_mi_like_p (uiout
))
8025 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
8026 ui_out_field_string (uiout
, "signal-name",
8027 gdb_signal_to_name (siggnal
));
8028 annotate_signal_name_end ();
8029 ui_out_text (uiout
, ", ");
8030 annotate_signal_string ();
8031 ui_out_field_string (uiout
, "signal-meaning",
8032 gdb_signal_to_string (siggnal
));
8034 if (siggnal
== GDB_SIGNAL_SEGV
)
8035 handle_segmentation_fault (uiout
);
8037 annotate_signal_string_end ();
8039 ui_out_text (uiout
, ".\n");
8043 print_no_history_reason (struct ui_out
*uiout
)
8045 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
8048 /* Print current location without a level number, if we have changed
8049 functions or hit a breakpoint. Print source line if we have one.
8050 bpstat_print contains the logic deciding in detail what to print,
8051 based on the event(s) that just occurred. */
8054 print_stop_location (struct target_waitstatus
*ws
)
8057 enum print_what source_flag
;
8058 int do_frame_printing
= 1;
8059 struct thread_info
*tp
= inferior_thread ();
8061 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8065 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8066 should) carry around the function and does (or should) use
8067 that when doing a frame comparison. */
8068 if (tp
->control
.stop_step
8069 && frame_id_eq (tp
->control
.step_frame_id
,
8070 get_frame_id (get_current_frame ()))
8071 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
8073 /* Finished step, just print source line. */
8074 source_flag
= SRC_LINE
;
8078 /* Print location and source line. */
8079 source_flag
= SRC_AND_LOC
;
8082 case PRINT_SRC_AND_LOC
:
8083 /* Print location and source line. */
8084 source_flag
= SRC_AND_LOC
;
8086 case PRINT_SRC_ONLY
:
8087 source_flag
= SRC_LINE
;
8090 /* Something bogus. */
8091 source_flag
= SRC_LINE
;
8092 do_frame_printing
= 0;
8095 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8098 /* The behavior of this routine with respect to the source
8100 SRC_LINE: Print only source line
8101 LOCATION: Print only location
8102 SRC_AND_LOC: Print location and source line. */
8103 if (do_frame_printing
)
8104 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8107 /* Cleanup that restores a previous current uiout. */
8110 restore_current_uiout_cleanup (void *arg
)
8112 struct ui_out
*saved_uiout
= (struct ui_out
*) arg
;
8114 current_uiout
= saved_uiout
;
8120 print_stop_event (struct ui_out
*uiout
)
8122 struct cleanup
*old_chain
;
8123 struct target_waitstatus last
;
8125 struct thread_info
*tp
;
8127 get_last_target_status (&last_ptid
, &last
);
8129 old_chain
= make_cleanup (restore_current_uiout_cleanup
, current_uiout
);
8130 current_uiout
= uiout
;
8132 print_stop_location (&last
);
8134 /* Display the auto-display expressions. */
8137 do_cleanups (old_chain
);
8139 tp
= inferior_thread ();
8140 if (tp
->thread_fsm
!= NULL
8141 && thread_fsm_finished_p (tp
->thread_fsm
))
8143 struct return_value_info
*rv
;
8145 rv
= thread_fsm_return_value (tp
->thread_fsm
);
8147 print_return_value (uiout
, rv
);
8154 maybe_remove_breakpoints (void)
8156 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
8158 if (remove_breakpoints ())
8160 target_terminal_ours_for_output ();
8161 printf_filtered (_("Cannot remove breakpoints because "
8162 "program is no longer writable.\nFurther "
8163 "execution is probably impossible.\n"));
8168 /* The execution context that just caused a normal stop. */
8175 /* The event PTID. */
8179 /* If stopp for a thread event, this is the thread that caused the
8181 struct thread_info
*thread
;
8183 /* The inferior that caused the stop. */
8187 /* Returns a new stop context. If stopped for a thread event, this
8188 takes a strong reference to the thread. */
8190 static struct stop_context
*
8191 save_stop_context (void)
8193 struct stop_context
*sc
= XNEW (struct stop_context
);
8195 sc
->stop_id
= get_stop_id ();
8196 sc
->ptid
= inferior_ptid
;
8197 sc
->inf_num
= current_inferior ()->num
;
8199 if (!ptid_equal (inferior_ptid
, null_ptid
))
8201 /* Take a strong reference so that the thread can't be deleted
8203 sc
->thread
= inferior_thread ();
8204 sc
->thread
->refcount
++;
8212 /* Release a stop context previously created with save_stop_context.
8213 Releases the strong reference to the thread as well. */
8216 release_stop_context_cleanup (void *arg
)
8218 struct stop_context
*sc
= (struct stop_context
*) arg
;
8220 if (sc
->thread
!= NULL
)
8221 sc
->thread
->refcount
--;
8225 /* Return true if the current context no longer matches the saved stop
8229 stop_context_changed (struct stop_context
*prev
)
8231 if (!ptid_equal (prev
->ptid
, inferior_ptid
))
8233 if (prev
->inf_num
!= current_inferior ()->num
)
8235 if (prev
->thread
!= NULL
&& prev
->thread
->state
!= THREAD_STOPPED
)
8237 if (get_stop_id () != prev
->stop_id
)
8247 struct target_waitstatus last
;
8249 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
8251 struct switch_thru_all_uis state
;
8253 get_last_target_status (&last_ptid
, &last
);
8257 /* If an exception is thrown from this point on, make sure to
8258 propagate GDB's knowledge of the executing state to the
8259 frontend/user running state. A QUIT is an easy exception to see
8260 here, so do this before any filtered output. */
8262 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
8263 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8264 || last
.kind
== TARGET_WAITKIND_EXITED
)
8266 /* On some targets, we may still have live threads in the
8267 inferior when we get a process exit event. E.g., for
8268 "checkpoint", when the current checkpoint/fork exits,
8269 linux-fork.c automatically switches to another fork from
8270 within target_mourn_inferior. */
8271 if (!ptid_equal (inferior_ptid
, null_ptid
))
8273 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
8274 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
8277 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8278 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
8280 /* As we're presenting a stop, and potentially removing breakpoints,
8281 update the thread list so we can tell whether there are threads
8282 running on the target. With target remote, for example, we can
8283 only learn about new threads when we explicitly update the thread
8284 list. Do this before notifying the interpreters about signal
8285 stops, end of stepping ranges, etc., so that the "new thread"
8286 output is emitted before e.g., "Program received signal FOO",
8287 instead of after. */
8288 update_thread_list ();
8290 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8291 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
8293 /* As with the notification of thread events, we want to delay
8294 notifying the user that we've switched thread context until
8295 the inferior actually stops.
8297 There's no point in saying anything if the inferior has exited.
8298 Note that SIGNALLED here means "exited with a signal", not
8299 "received a signal".
8301 Also skip saying anything in non-stop mode. In that mode, as we
8302 don't want GDB to switch threads behind the user's back, to avoid
8303 races where the user is typing a command to apply to thread x,
8304 but GDB switches to thread y before the user finishes entering
8305 the command, fetch_inferior_event installs a cleanup to restore
8306 the current thread back to the thread the user had selected right
8307 after this event is handled, so we're not really switching, only
8308 informing of a stop. */
8310 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
8311 && target_has_execution
8312 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8313 && last
.kind
!= TARGET_WAITKIND_EXITED
8314 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8316 SWITCH_THRU_ALL_UIS (state
)
8318 target_terminal_ours_for_output ();
8319 printf_filtered (_("[Switching to %s]\n"),
8320 target_pid_to_str (inferior_ptid
));
8321 annotate_thread_changed ();
8323 previous_inferior_ptid
= inferior_ptid
;
8326 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8328 SWITCH_THRU_ALL_UIS (state
)
8329 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8331 target_terminal_ours_for_output ();
8332 printf_filtered (_("No unwaited-for children left.\n"));
8336 /* Note: this depends on the update_thread_list call above. */
8337 maybe_remove_breakpoints ();
8339 /* If an auto-display called a function and that got a signal,
8340 delete that auto-display to avoid an infinite recursion. */
8342 if (stopped_by_random_signal
)
8343 disable_current_display ();
8345 SWITCH_THRU_ALL_UIS (state
)
8347 async_enable_stdin ();
8350 /* Let the user/frontend see the threads as stopped. */
8351 do_cleanups (old_chain
);
8353 /* Select innermost stack frame - i.e., current frame is frame 0,
8354 and current location is based on that. Handle the case where the
8355 dummy call is returning after being stopped. E.g. the dummy call
8356 previously hit a breakpoint. (If the dummy call returns
8357 normally, we won't reach here.) Do this before the stop hook is
8358 run, so that it doesn't get to see the temporary dummy frame,
8359 which is not where we'll present the stop. */
8360 if (has_stack_frames ())
8362 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8364 /* Pop the empty frame that contains the stack dummy. This
8365 also restores inferior state prior to the call (struct
8366 infcall_suspend_state). */
8367 struct frame_info
*frame
= get_current_frame ();
8369 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8371 /* frame_pop calls reinit_frame_cache as the last thing it
8372 does which means there's now no selected frame. */
8375 select_frame (get_current_frame ());
8377 /* Set the current source location. */
8378 set_current_sal_from_frame (get_current_frame ());
8381 /* Look up the hook_stop and run it (CLI internally handles problem
8382 of stop_command's pre-hook not existing). */
8383 if (stop_command
!= NULL
)
8385 struct stop_context
*saved_context
= save_stop_context ();
8386 struct cleanup
*old_chain
8387 = make_cleanup (release_stop_context_cleanup
, saved_context
);
8389 catch_errors (hook_stop_stub
, stop_command
,
8390 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
8392 /* If the stop hook resumes the target, then there's no point in
8393 trying to notify about the previous stop; its context is
8394 gone. Likewise if the command switches thread or inferior --
8395 the observers would print a stop for the wrong
8397 if (stop_context_changed (saved_context
))
8399 do_cleanups (old_chain
);
8402 do_cleanups (old_chain
);
8405 /* Notify observers about the stop. This is where the interpreters
8406 print the stop event. */
8407 if (!ptid_equal (inferior_ptid
, null_ptid
))
8408 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
8411 observer_notify_normal_stop (NULL
, stop_print_frame
);
8413 annotate_stopped ();
8415 if (target_has_execution
)
8417 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8418 && last
.kind
!= TARGET_WAITKIND_EXITED
)
8419 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8420 Delete any breakpoint that is to be deleted at the next stop. */
8421 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8424 /* Try to get rid of automatically added inferiors that are no
8425 longer needed. Keeping those around slows down things linearly.
8426 Note that this never removes the current inferior. */
8433 hook_stop_stub (void *cmd
)
8435 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
8440 signal_stop_state (int signo
)
8442 return signal_stop
[signo
];
8446 signal_print_state (int signo
)
8448 return signal_print
[signo
];
8452 signal_pass_state (int signo
)
8454 return signal_program
[signo
];
8458 signal_cache_update (int signo
)
8462 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8463 signal_cache_update (signo
);
8468 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8469 && signal_print
[signo
] == 0
8470 && signal_program
[signo
] == 1
8471 && signal_catch
[signo
] == 0);
8475 signal_stop_update (int signo
, int state
)
8477 int ret
= signal_stop
[signo
];
8479 signal_stop
[signo
] = state
;
8480 signal_cache_update (signo
);
8485 signal_print_update (int signo
, int state
)
8487 int ret
= signal_print
[signo
];
8489 signal_print
[signo
] = state
;
8490 signal_cache_update (signo
);
8495 signal_pass_update (int signo
, int state
)
8497 int ret
= signal_program
[signo
];
8499 signal_program
[signo
] = state
;
8500 signal_cache_update (signo
);
8504 /* Update the global 'signal_catch' from INFO and notify the
8508 signal_catch_update (const unsigned int *info
)
8512 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8513 signal_catch
[i
] = info
[i
] > 0;
8514 signal_cache_update (-1);
8515 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8519 sig_print_header (void)
8521 printf_filtered (_("Signal Stop\tPrint\tPass "
8522 "to program\tDescription\n"));
8526 sig_print_info (enum gdb_signal oursig
)
8528 const char *name
= gdb_signal_to_name (oursig
);
8529 int name_padding
= 13 - strlen (name
);
8531 if (name_padding
<= 0)
8534 printf_filtered ("%s", name
);
8535 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8536 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8537 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8538 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8539 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8542 /* Specify how various signals in the inferior should be handled. */
8545 handle_command (char *args
, int from_tty
)
8548 int digits
, wordlen
;
8549 int sigfirst
, signum
, siglast
;
8550 enum gdb_signal oursig
;
8553 unsigned char *sigs
;
8554 struct cleanup
*old_chain
;
8558 error_no_arg (_("signal to handle"));
8561 /* Allocate and zero an array of flags for which signals to handle. */
8563 nsigs
= (int) GDB_SIGNAL_LAST
;
8564 sigs
= (unsigned char *) alloca (nsigs
);
8565 memset (sigs
, 0, nsigs
);
8567 /* Break the command line up into args. */
8569 argv
= gdb_buildargv (args
);
8570 old_chain
= make_cleanup_freeargv (argv
);
8572 /* Walk through the args, looking for signal oursigs, signal names, and
8573 actions. Signal numbers and signal names may be interspersed with
8574 actions, with the actions being performed for all signals cumulatively
8575 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8577 while (*argv
!= NULL
)
8579 wordlen
= strlen (*argv
);
8580 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
8584 sigfirst
= siglast
= -1;
8586 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
8588 /* Apply action to all signals except those used by the
8589 debugger. Silently skip those. */
8592 siglast
= nsigs
- 1;
8594 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
8596 SET_SIGS (nsigs
, sigs
, signal_stop
);
8597 SET_SIGS (nsigs
, sigs
, signal_print
);
8599 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
8601 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8603 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
8605 SET_SIGS (nsigs
, sigs
, signal_print
);
8607 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
8609 SET_SIGS (nsigs
, sigs
, signal_program
);
8611 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
8613 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8615 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
8617 SET_SIGS (nsigs
, sigs
, signal_program
);
8619 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
8621 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8622 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8624 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
8626 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8628 else if (digits
> 0)
8630 /* It is numeric. The numeric signal refers to our own
8631 internal signal numbering from target.h, not to host/target
8632 signal number. This is a feature; users really should be
8633 using symbolic names anyway, and the common ones like
8634 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8636 sigfirst
= siglast
= (int)
8637 gdb_signal_from_command (atoi (*argv
));
8638 if ((*argv
)[digits
] == '-')
8641 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
8643 if (sigfirst
> siglast
)
8645 /* Bet he didn't figure we'd think of this case... */
8653 oursig
= gdb_signal_from_name (*argv
);
8654 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8656 sigfirst
= siglast
= (int) oursig
;
8660 /* Not a number and not a recognized flag word => complain. */
8661 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
8665 /* If any signal numbers or symbol names were found, set flags for
8666 which signals to apply actions to. */
8668 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8670 switch ((enum gdb_signal
) signum
)
8672 case GDB_SIGNAL_TRAP
:
8673 case GDB_SIGNAL_INT
:
8674 if (!allsigs
&& !sigs
[signum
])
8676 if (query (_("%s is used by the debugger.\n\
8677 Are you sure you want to change it? "),
8678 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8684 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8685 gdb_flush (gdb_stdout
);
8690 case GDB_SIGNAL_DEFAULT
:
8691 case GDB_SIGNAL_UNKNOWN
:
8692 /* Make sure that "all" doesn't print these. */
8703 for (signum
= 0; signum
< nsigs
; signum
++)
8706 signal_cache_update (-1);
8707 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8708 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8712 /* Show the results. */
8713 sig_print_header ();
8714 for (; signum
< nsigs
; signum
++)
8716 sig_print_info ((enum gdb_signal
) signum
);
8722 do_cleanups (old_chain
);
8725 /* Complete the "handle" command. */
8727 static VEC (char_ptr
) *
8728 handle_completer (struct cmd_list_element
*ignore
,
8729 const char *text
, const char *word
)
8731 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
8732 static const char * const keywords
[] =
8746 vec_signals
= signal_completer (ignore
, text
, word
);
8747 vec_keywords
= complete_on_enum (keywords
, word
, word
);
8749 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
8750 VEC_free (char_ptr
, vec_signals
);
8751 VEC_free (char_ptr
, vec_keywords
);
8756 gdb_signal_from_command (int num
)
8758 if (num
>= 1 && num
<= 15)
8759 return (enum gdb_signal
) num
;
8760 error (_("Only signals 1-15 are valid as numeric signals.\n\
8761 Use \"info signals\" for a list of symbolic signals."));
8764 /* Print current contents of the tables set by the handle command.
8765 It is possible we should just be printing signals actually used
8766 by the current target (but for things to work right when switching
8767 targets, all signals should be in the signal tables). */
8770 signals_info (char *signum_exp
, int from_tty
)
8772 enum gdb_signal oursig
;
8774 sig_print_header ();
8778 /* First see if this is a symbol name. */
8779 oursig
= gdb_signal_from_name (signum_exp
);
8780 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8782 /* No, try numeric. */
8784 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8786 sig_print_info (oursig
);
8790 printf_filtered ("\n");
8791 /* These ugly casts brought to you by the native VAX compiler. */
8792 for (oursig
= GDB_SIGNAL_FIRST
;
8793 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8794 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8798 if (oursig
!= GDB_SIGNAL_UNKNOWN
8799 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8800 sig_print_info (oursig
);
8803 printf_filtered (_("\nUse the \"handle\" command "
8804 "to change these tables.\n"));
8807 /* The $_siginfo convenience variable is a bit special. We don't know
8808 for sure the type of the value until we actually have a chance to
8809 fetch the data. The type can change depending on gdbarch, so it is
8810 also dependent on which thread you have selected.
8812 1. making $_siginfo be an internalvar that creates a new value on
8815 2. making the value of $_siginfo be an lval_computed value. */
8817 /* This function implements the lval_computed support for reading a
8821 siginfo_value_read (struct value
*v
)
8823 LONGEST transferred
;
8825 /* If we can access registers, so can we access $_siginfo. Likewise
8827 validate_registers_access ();
8830 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8832 value_contents_all_raw (v
),
8834 TYPE_LENGTH (value_type (v
)));
8836 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8837 error (_("Unable to read siginfo"));
8840 /* This function implements the lval_computed support for writing a
8844 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8846 LONGEST transferred
;
8848 /* If we can access registers, so can we access $_siginfo. Likewise
8850 validate_registers_access ();
8852 transferred
= target_write (¤t_target
,
8853 TARGET_OBJECT_SIGNAL_INFO
,
8855 value_contents_all_raw (fromval
),
8857 TYPE_LENGTH (value_type (fromval
)));
8859 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8860 error (_("Unable to write siginfo"));
8863 static const struct lval_funcs siginfo_value_funcs
=
8869 /* Return a new value with the correct type for the siginfo object of
8870 the current thread using architecture GDBARCH. Return a void value
8871 if there's no object available. */
8873 static struct value
*
8874 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8877 if (target_has_stack
8878 && !ptid_equal (inferior_ptid
, null_ptid
)
8879 && gdbarch_get_siginfo_type_p (gdbarch
))
8881 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8883 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8886 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8890 /* infcall_suspend_state contains state about the program itself like its
8891 registers and any signal it received when it last stopped.
8892 This state must be restored regardless of how the inferior function call
8893 ends (either successfully, or after it hits a breakpoint or signal)
8894 if the program is to properly continue where it left off. */
8896 struct infcall_suspend_state
8898 struct thread_suspend_state thread_suspend
;
8902 struct regcache
*registers
;
8904 /* Format of SIGINFO_DATA or NULL if it is not present. */
8905 struct gdbarch
*siginfo_gdbarch
;
8907 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8908 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8909 content would be invalid. */
8910 gdb_byte
*siginfo_data
;
8913 struct infcall_suspend_state
*
8914 save_infcall_suspend_state (void)
8916 struct infcall_suspend_state
*inf_state
;
8917 struct thread_info
*tp
= inferior_thread ();
8918 struct regcache
*regcache
= get_current_regcache ();
8919 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8920 gdb_byte
*siginfo_data
= NULL
;
8922 if (gdbarch_get_siginfo_type_p (gdbarch
))
8924 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8925 size_t len
= TYPE_LENGTH (type
);
8926 struct cleanup
*back_to
;
8928 siginfo_data
= (gdb_byte
*) xmalloc (len
);
8929 back_to
= make_cleanup (xfree
, siginfo_data
);
8931 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8932 siginfo_data
, 0, len
) == len
)
8933 discard_cleanups (back_to
);
8936 /* Errors ignored. */
8937 do_cleanups (back_to
);
8938 siginfo_data
= NULL
;
8942 inf_state
= XCNEW (struct infcall_suspend_state
);
8946 inf_state
->siginfo_gdbarch
= gdbarch
;
8947 inf_state
->siginfo_data
= siginfo_data
;
8950 inf_state
->thread_suspend
= tp
->suspend
;
8952 /* run_inferior_call will not use the signal due to its `proceed' call with
8953 GDB_SIGNAL_0 anyway. */
8954 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8956 inf_state
->stop_pc
= stop_pc
;
8958 inf_state
->registers
= regcache_dup (regcache
);
8963 /* Restore inferior session state to INF_STATE. */
8966 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8968 struct thread_info
*tp
= inferior_thread ();
8969 struct regcache
*regcache
= get_current_regcache ();
8970 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
8972 tp
->suspend
= inf_state
->thread_suspend
;
8974 stop_pc
= inf_state
->stop_pc
;
8976 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8978 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8980 /* Errors ignored. */
8981 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8982 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8985 /* The inferior can be gone if the user types "print exit(0)"
8986 (and perhaps other times). */
8987 if (target_has_execution
)
8988 /* NB: The register write goes through to the target. */
8989 regcache_cpy (regcache
, inf_state
->registers
);
8991 discard_infcall_suspend_state (inf_state
);
8995 do_restore_infcall_suspend_state_cleanup (void *state
)
8997 restore_infcall_suspend_state ((struct infcall_suspend_state
*) state
);
9001 make_cleanup_restore_infcall_suspend_state
9002 (struct infcall_suspend_state
*inf_state
)
9004 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
9008 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
9010 regcache_xfree (inf_state
->registers
);
9011 xfree (inf_state
->siginfo_data
);
9016 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
9018 return inf_state
->registers
;
9021 /* infcall_control_state contains state regarding gdb's control of the
9022 inferior itself like stepping control. It also contains session state like
9023 the user's currently selected frame. */
9025 struct infcall_control_state
9027 struct thread_control_state thread_control
;
9028 struct inferior_control_state inferior_control
;
9031 enum stop_stack_kind stop_stack_dummy
;
9032 int stopped_by_random_signal
;
9034 /* ID if the selected frame when the inferior function call was made. */
9035 struct frame_id selected_frame_id
;
9038 /* Save all of the information associated with the inferior<==>gdb
9041 struct infcall_control_state
*
9042 save_infcall_control_state (void)
9044 struct infcall_control_state
*inf_status
=
9045 XNEW (struct infcall_control_state
);
9046 struct thread_info
*tp
= inferior_thread ();
9047 struct inferior
*inf
= current_inferior ();
9049 inf_status
->thread_control
= tp
->control
;
9050 inf_status
->inferior_control
= inf
->control
;
9052 tp
->control
.step_resume_breakpoint
= NULL
;
9053 tp
->control
.exception_resume_breakpoint
= NULL
;
9055 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9056 chain. If caller's caller is walking the chain, they'll be happier if we
9057 hand them back the original chain when restore_infcall_control_state is
9059 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9062 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9063 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9065 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
9071 restore_selected_frame (void *args
)
9073 struct frame_id
*fid
= (struct frame_id
*) args
;
9074 struct frame_info
*frame
;
9076 frame
= frame_find_by_id (*fid
);
9078 /* If inf_status->selected_frame_id is NULL, there was no previously
9082 warning (_("Unable to restore previously selected frame."));
9086 select_frame (frame
);
9091 /* Restore inferior session state to INF_STATUS. */
9094 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9096 struct thread_info
*tp
= inferior_thread ();
9097 struct inferior
*inf
= current_inferior ();
9099 if (tp
->control
.step_resume_breakpoint
)
9100 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9102 if (tp
->control
.exception_resume_breakpoint
)
9103 tp
->control
.exception_resume_breakpoint
->disposition
9104 = disp_del_at_next_stop
;
9106 /* Handle the bpstat_copy of the chain. */
9107 bpstat_clear (&tp
->control
.stop_bpstat
);
9109 tp
->control
= inf_status
->thread_control
;
9110 inf
->control
= inf_status
->inferior_control
;
9113 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9114 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9116 if (target_has_stack
)
9118 /* The point of catch_errors is that if the stack is clobbered,
9119 walking the stack might encounter a garbage pointer and
9120 error() trying to dereference it. */
9122 (restore_selected_frame
, &inf_status
->selected_frame_id
,
9123 "Unable to restore previously selected frame:\n",
9124 RETURN_MASK_ERROR
) == 0)
9125 /* Error in restoring the selected frame. Select the innermost
9127 select_frame (get_current_frame ());
9134 do_restore_infcall_control_state_cleanup (void *sts
)
9136 restore_infcall_control_state ((struct infcall_control_state
*) sts
);
9140 make_cleanup_restore_infcall_control_state
9141 (struct infcall_control_state
*inf_status
)
9143 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
9147 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9149 if (inf_status
->thread_control
.step_resume_breakpoint
)
9150 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9151 = disp_del_at_next_stop
;
9153 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9154 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9155 = disp_del_at_next_stop
;
9157 /* See save_infcall_control_state for info on stop_bpstat. */
9158 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9163 /* restore_inferior_ptid() will be used by the cleanup machinery
9164 to restore the inferior_ptid value saved in a call to
9165 save_inferior_ptid(). */
9168 restore_inferior_ptid (void *arg
)
9170 ptid_t
*saved_ptid_ptr
= (ptid_t
*) arg
;
9172 inferior_ptid
= *saved_ptid_ptr
;
9176 /* Save the value of inferior_ptid so that it may be restored by a
9177 later call to do_cleanups(). Returns the struct cleanup pointer
9178 needed for later doing the cleanup. */
9181 save_inferior_ptid (void)
9183 ptid_t
*saved_ptid_ptr
= XNEW (ptid_t
);
9185 *saved_ptid_ptr
= inferior_ptid
;
9186 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
9192 clear_exit_convenience_vars (void)
9194 clear_internalvar (lookup_internalvar ("_exitsignal"));
9195 clear_internalvar (lookup_internalvar ("_exitcode"));
9199 /* User interface for reverse debugging:
9200 Set exec-direction / show exec-direction commands
9201 (returns error unless target implements to_set_exec_direction method). */
9203 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9204 static const char exec_forward
[] = "forward";
9205 static const char exec_reverse
[] = "reverse";
9206 static const char *exec_direction
= exec_forward
;
9207 static const char *const exec_direction_names
[] = {
9214 set_exec_direction_func (char *args
, int from_tty
,
9215 struct cmd_list_element
*cmd
)
9217 if (target_can_execute_reverse
)
9219 if (!strcmp (exec_direction
, exec_forward
))
9220 execution_direction
= EXEC_FORWARD
;
9221 else if (!strcmp (exec_direction
, exec_reverse
))
9222 execution_direction
= EXEC_REVERSE
;
9226 exec_direction
= exec_forward
;
9227 error (_("Target does not support this operation."));
9232 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9233 struct cmd_list_element
*cmd
, const char *value
)
9235 switch (execution_direction
) {
9237 fprintf_filtered (out
, _("Forward.\n"));
9240 fprintf_filtered (out
, _("Reverse.\n"));
9243 internal_error (__FILE__
, __LINE__
,
9244 _("bogus execution_direction value: %d"),
9245 (int) execution_direction
);
9250 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9251 struct cmd_list_element
*c
, const char *value
)
9253 fprintf_filtered (file
, _("Resuming the execution of threads "
9254 "of all processes is %s.\n"), value
);
9257 /* Implementation of `siginfo' variable. */
9259 static const struct internalvar_funcs siginfo_funcs
=
9266 /* Callback for infrun's target events source. This is marked when a
9267 thread has a pending status to process. */
9270 infrun_async_inferior_event_handler (gdb_client_data data
)
9272 inferior_event_handler (INF_REG_EVENT
, NULL
);
9276 _initialize_infrun (void)
9280 struct cmd_list_element
*c
;
9282 /* Register extra event sources in the event loop. */
9283 infrun_async_inferior_event_token
9284 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
9286 add_info ("signals", signals_info
, _("\
9287 What debugger does when program gets various signals.\n\
9288 Specify a signal as argument to print info on that signal only."));
9289 add_info_alias ("handle", "signals", 0);
9291 c
= add_com ("handle", class_run
, handle_command
, _("\
9292 Specify how to handle signals.\n\
9293 Usage: handle SIGNAL [ACTIONS]\n\
9294 Args are signals and actions to apply to those signals.\n\
9295 If no actions are specified, the current settings for the specified signals\n\
9296 will be displayed instead.\n\
9298 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9299 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9300 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9301 The special arg \"all\" is recognized to mean all signals except those\n\
9302 used by the debugger, typically SIGTRAP and SIGINT.\n\
9304 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9305 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9306 Stop means reenter debugger if this signal happens (implies print).\n\
9307 Print means print a message if this signal happens.\n\
9308 Pass means let program see this signal; otherwise program doesn't know.\n\
9309 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9310 Pass and Stop may be combined.\n\
9312 Multiple signals may be specified. Signal numbers and signal names\n\
9313 may be interspersed with actions, with the actions being performed for\n\
9314 all signals cumulatively specified."));
9315 set_cmd_completer (c
, handle_completer
);
9318 stop_command
= add_cmd ("stop", class_obscure
,
9319 not_just_help_class_command
, _("\
9320 There is no `stop' command, but you can set a hook on `stop'.\n\
9321 This allows you to set a list of commands to be run each time execution\n\
9322 of the program stops."), &cmdlist
);
9324 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
9325 Set inferior debugging."), _("\
9326 Show inferior debugging."), _("\
9327 When non-zero, inferior specific debugging is enabled."),
9330 &setdebuglist
, &showdebuglist
);
9332 add_setshow_boolean_cmd ("displaced", class_maintenance
,
9333 &debug_displaced
, _("\
9334 Set displaced stepping debugging."), _("\
9335 Show displaced stepping debugging."), _("\
9336 When non-zero, displaced stepping specific debugging is enabled."),
9338 show_debug_displaced
,
9339 &setdebuglist
, &showdebuglist
);
9341 add_setshow_boolean_cmd ("non-stop", no_class
,
9343 Set whether gdb controls the inferior in non-stop mode."), _("\
9344 Show whether gdb controls the inferior in non-stop mode."), _("\
9345 When debugging a multi-threaded program and this setting is\n\
9346 off (the default, also called all-stop mode), when one thread stops\n\
9347 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9348 all other threads in the program while you interact with the thread of\n\
9349 interest. When you continue or step a thread, you can allow the other\n\
9350 threads to run, or have them remain stopped, but while you inspect any\n\
9351 thread's state, all threads stop.\n\
9353 In non-stop mode, when one thread stops, other threads can continue\n\
9354 to run freely. You'll be able to step each thread independently,\n\
9355 leave it stopped or free to run as needed."),
9361 numsigs
= (int) GDB_SIGNAL_LAST
;
9362 signal_stop
= XNEWVEC (unsigned char, numsigs
);
9363 signal_print
= XNEWVEC (unsigned char, numsigs
);
9364 signal_program
= XNEWVEC (unsigned char, numsigs
);
9365 signal_catch
= XNEWVEC (unsigned char, numsigs
);
9366 signal_pass
= XNEWVEC (unsigned char, numsigs
);
9367 for (i
= 0; i
< numsigs
; i
++)
9370 signal_print
[i
] = 1;
9371 signal_program
[i
] = 1;
9372 signal_catch
[i
] = 0;
9375 /* Signals caused by debugger's own actions should not be given to
9376 the program afterwards.
9378 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9379 explicitly specifies that it should be delivered to the target
9380 program. Typically, that would occur when a user is debugging a
9381 target monitor on a simulator: the target monitor sets a
9382 breakpoint; the simulator encounters this breakpoint and halts
9383 the simulation handing control to GDB; GDB, noting that the stop
9384 address doesn't map to any known breakpoint, returns control back
9385 to the simulator; the simulator then delivers the hardware
9386 equivalent of a GDB_SIGNAL_TRAP to the program being
9388 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9389 signal_program
[GDB_SIGNAL_INT
] = 0;
9391 /* Signals that are not errors should not normally enter the debugger. */
9392 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9393 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9394 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9395 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9396 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9397 signal_print
[GDB_SIGNAL_PROF
] = 0;
9398 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9399 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9400 signal_stop
[GDB_SIGNAL_IO
] = 0;
9401 signal_print
[GDB_SIGNAL_IO
] = 0;
9402 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9403 signal_print
[GDB_SIGNAL_POLL
] = 0;
9404 signal_stop
[GDB_SIGNAL_URG
] = 0;
9405 signal_print
[GDB_SIGNAL_URG
] = 0;
9406 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9407 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9408 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9409 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9411 /* These signals are used internally by user-level thread
9412 implementations. (See signal(5) on Solaris.) Like the above
9413 signals, a healthy program receives and handles them as part of
9414 its normal operation. */
9415 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9416 signal_print
[GDB_SIGNAL_LWP
] = 0;
9417 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9418 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9419 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9420 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9422 /* Update cached state. */
9423 signal_cache_update (-1);
9425 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9426 &stop_on_solib_events
, _("\
9427 Set stopping for shared library events."), _("\
9428 Show stopping for shared library events."), _("\
9429 If nonzero, gdb will give control to the user when the dynamic linker\n\
9430 notifies gdb of shared library events. The most common event of interest\n\
9431 to the user would be loading/unloading of a new library."),
9432 set_stop_on_solib_events
,
9433 show_stop_on_solib_events
,
9434 &setlist
, &showlist
);
9436 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9437 follow_fork_mode_kind_names
,
9438 &follow_fork_mode_string
, _("\
9439 Set debugger response to a program call of fork or vfork."), _("\
9440 Show debugger response to a program call of fork or vfork."), _("\
9441 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9442 parent - the original process is debugged after a fork\n\
9443 child - the new process is debugged after a fork\n\
9444 The unfollowed process will continue to run.\n\
9445 By default, the debugger will follow the parent process."),
9447 show_follow_fork_mode_string
,
9448 &setlist
, &showlist
);
9450 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9451 follow_exec_mode_names
,
9452 &follow_exec_mode_string
, _("\
9453 Set debugger response to a program call of exec."), _("\
9454 Show debugger response to a program call of exec."), _("\
9455 An exec call replaces the program image of a process.\n\
9457 follow-exec-mode can be:\n\
9459 new - the debugger creates a new inferior and rebinds the process\n\
9460 to this new inferior. The program the process was running before\n\
9461 the exec call can be restarted afterwards by restarting the original\n\
9464 same - the debugger keeps the process bound to the same inferior.\n\
9465 The new executable image replaces the previous executable loaded in\n\
9466 the inferior. Restarting the inferior after the exec call restarts\n\
9467 the executable the process was running after the exec call.\n\
9469 By default, the debugger will use the same inferior."),
9471 show_follow_exec_mode_string
,
9472 &setlist
, &showlist
);
9474 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9475 scheduler_enums
, &scheduler_mode
, _("\
9476 Set mode for locking scheduler during execution."), _("\
9477 Show mode for locking scheduler during execution."), _("\
9478 off == no locking (threads may preempt at any time)\n\
9479 on == full locking (no thread except the current thread may run)\n\
9480 This applies to both normal execution and replay mode.\n\
9481 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9482 In this mode, other threads may run during other commands.\n\
9483 This applies to both normal execution and replay mode.\n\
9484 replay == scheduler locked in replay mode and unlocked during normal execution."),
9485 set_schedlock_func
, /* traps on target vector */
9486 show_scheduler_mode
,
9487 &setlist
, &showlist
);
9489 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9490 Set mode for resuming threads of all processes."), _("\
9491 Show mode for resuming threads of all processes."), _("\
9492 When on, execution commands (such as 'continue' or 'next') resume all\n\
9493 threads of all processes. When off (which is the default), execution\n\
9494 commands only resume the threads of the current process. The set of\n\
9495 threads that are resumed is further refined by the scheduler-locking\n\
9496 mode (see help set scheduler-locking)."),
9498 show_schedule_multiple
,
9499 &setlist
, &showlist
);
9501 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9502 Set mode of the step operation."), _("\
9503 Show mode of the step operation."), _("\
9504 When set, doing a step over a function without debug line information\n\
9505 will stop at the first instruction of that function. Otherwise, the\n\
9506 function is skipped and the step command stops at a different source line."),
9508 show_step_stop_if_no_debug
,
9509 &setlist
, &showlist
);
9511 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9512 &can_use_displaced_stepping
, _("\
9513 Set debugger's willingness to use displaced stepping."), _("\
9514 Show debugger's willingness to use displaced stepping."), _("\
9515 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9516 supported by the target architecture. If off, gdb will not use displaced\n\
9517 stepping to step over breakpoints, even if such is supported by the target\n\
9518 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9519 if the target architecture supports it and non-stop mode is active, but will not\n\
9520 use it in all-stop mode (see help set non-stop)."),
9522 show_can_use_displaced_stepping
,
9523 &setlist
, &showlist
);
9525 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9526 &exec_direction
, _("Set direction of execution.\n\
9527 Options are 'forward' or 'reverse'."),
9528 _("Show direction of execution (forward/reverse)."),
9529 _("Tells gdb whether to execute forward or backward."),
9530 set_exec_direction_func
, show_exec_direction_func
,
9531 &setlist
, &showlist
);
9533 /* Set/show detach-on-fork: user-settable mode. */
9535 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9536 Set whether gdb will detach the child of a fork."), _("\
9537 Show whether gdb will detach the child of a fork."), _("\
9538 Tells gdb whether to detach the child of a fork."),
9539 NULL
, NULL
, &setlist
, &showlist
);
9541 /* Set/show disable address space randomization mode. */
9543 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9544 &disable_randomization
, _("\
9545 Set disabling of debuggee's virtual address space randomization."), _("\
9546 Show disabling of debuggee's virtual address space randomization."), _("\
9547 When this mode is on (which is the default), randomization of the virtual\n\
9548 address space is disabled. Standalone programs run with the randomization\n\
9549 enabled by default on some platforms."),
9550 &set_disable_randomization
,
9551 &show_disable_randomization
,
9552 &setlist
, &showlist
);
9554 /* ptid initializations */
9555 inferior_ptid
= null_ptid
;
9556 target_last_wait_ptid
= minus_one_ptid
;
9558 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
9559 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
9560 observer_attach_thread_exit (infrun_thread_thread_exit
);
9561 observer_attach_inferior_exit (infrun_inferior_exit
);
9563 /* Explicitly create without lookup, since that tries to create a
9564 value with a void typed value, and when we get here, gdbarch
9565 isn't initialized yet. At this point, we're quite sure there
9566 isn't another convenience variable of the same name. */
9567 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9569 add_setshow_boolean_cmd ("observer", no_class
,
9570 &observer_mode_1
, _("\
9571 Set whether gdb controls the inferior in observer mode."), _("\
9572 Show whether gdb controls the inferior in observer mode."), _("\
9573 In observer mode, GDB can get data from the inferior, but not\n\
9574 affect its execution. Registers and memory may not be changed,\n\
9575 breakpoints may not be set, and the program cannot be interrupted\n\